[RFC PATCH 00/24] crypto: Add generic Kerberos library with AEAD template for hash-then-crypt

[RFC PATCH 00/24] crypto: Add generic Kerberos library with AEAD template for hash-then-crypt

[David Howells]

Hi Herbert, Chuck,

Here's yet another go at a generic Kerberos crypto library in the kernel so
that I can share code between rxrpc and sunrpc (and cifs?).  I derived some
of the parts from the sunrpc gss library and added more advanced AES and
Camellia crypto.

I added an addition AEAD template type, derived from authenc, that does
hash-then-crypt rather than crypt-then-hash as authenc does.  I called it
"krb5enc" for want of a better name.  Possibly I should call it "hashenc"
or something like that.

I went back to my previous more library-based approach, but for encrypt
mode, I replaced the separate skcipher and shash objects with a single
templated AEAD object - either krb5enc (AES+SHA1 and Camellia) or authenc
(AES+SHA2).

Apart from that, things are much as they were previously from the point of
view of someone using the API.  There's a new pair of functions that, given
an encoding type, a key and a usage value, will derive the necessary keys
and return an AEAD or hash handle.  These handles can then be passed to
operation functions that will do the actual work of performing an
encryption, a decryption, MIC generation or MIC verification.

Querying functions are also available to look up an encoding type table by
kerberos protocol number and to help manage message layout.

This library has its own self-testing framework that checks more things
than is possible with the testmgr, including subkey derivation.  It also
checks things about the output of encrypt + decrypt that testmgr doesn't.
That said, testmgr is also provisioned with some encryption and
checksumming tests for Camilla and AES2, though these have to be
provisioned with the intermediate subkeys rather than the transport key.

Note that, for purposes of illustration, I've included some rxrpc patches
that use this interface to implement the rxgk Rx security class.  The
branch also is based on net-next that carries some rxrpc patches that are a
prerequisite for this, but the crypto patches don't need it.

---
The patches can be found here also:

	http://git.kernel.org/cgit/linux/kernel/git/dhowells/linux-fs.git/log/?h=crypto-krb5

David

David Howells (24):
  crypto/krb5: Add API Documentation
  crypto/krb5: Add some constants out of sunrpc headers
  crypto: Add 'krb5enc' hash and cipher AEAD algorithm
  crypto/krb5: Test manager data
  crypto/krb5: Implement Kerberos crypto core
  crypto/krb5: Add an API to query the layout of the crypto section
  crypto/krb5: Add an API to alloc and prepare a crypto object
  crypto/krb5: Add an API to perform requests
  crypto/krb5: Provide infrastructure and key derivation
  crypto/krb5: Implement the Kerberos5 rfc3961 key derivation
  crypto/krb5: Provide RFC3961 setkey packaging functions
  crypto/krb5: Implement the Kerberos5 rfc3961 encrypt and decrypt
    functions
  crypto/krb5: Implement the Kerberos5 rfc3961 get_mic and verify_mic
  crypto/krb5: Implement the AES enctypes from rfc3962
  crypto/krb5: Implement the AES enctypes from rfc8009
  crypto/krb5: Implement the AES encrypt/decrypt from rfc8009
  crypto/krb5: Implement crypto self-testing
  crypto/krb5: Add the AES self-testing data from rfc8009
  crypto/krb5: Implement the Camellia enctypes from rfc6803
  rxrpc: Add the security index for yfs-rxgk
  rxrpc: Add YFS RxGK (GSSAPI) security class
  rxrpc: rxgk: Provide infrastructure and key derivation
  rxrpc: rxgk: Implement the yfs-rxgk security class (GSSAPI)
  rxrpc: rxgk: Implement connection rekeying

 Documentation/crypto/index.rst   |    1 +
 Documentation/crypto/krb5.rst    |  262 +++++++
 crypto/Kconfig                   |   13 +
 crypto/Makefile                  |    3 +
 crypto/krb5/Kconfig              |   26 +
 crypto/krb5/Makefile             |   18 +
 crypto/krb5/internal.h           |  257 +++++++
 crypto/krb5/krb5_api.c           |  452 ++++++++++++
 crypto/krb5/krb5_kdf.c           |  145 ++++
 crypto/krb5/rfc3961_simplified.c |  791 ++++++++++++++++++++
 crypto/krb5/rfc3962_aes.c        |  115 +++
 crypto/krb5/rfc6803_camellia.c   |  237 ++++++
 crypto/krb5/rfc8009_aes2.c       |  431 +++++++++++
 crypto/krb5/selftest.c           |  544 ++++++++++++++
 crypto/krb5/selftest_data.c      |  291 ++++++++
 crypto/krb5enc.c                 |  491 +++++++++++++
 crypto/testmgr.c                 |   16 +
 crypto/testmgr.h                 |  401 ++++++++++
 fs/afs/misc.c                    |   13 +
 include/crypto/krb5.h            |  167 +++++
 include/keys/rxrpc-type.h        |   17 +
 include/trace/events/rxrpc.h     |   36 +
 include/uapi/linux/rxrpc.h       |   17 +
 net/rxrpc/Kconfig                |   10 +
 net/rxrpc/Makefile               |    5 +-
 net/rxrpc/ar-internal.h          |   22 +
 net/rxrpc/conn_event.c           |    2 +-
 net/rxrpc/conn_object.c          |    1 +
 net/rxrpc/key.c                  |  183 +++++
 net/rxrpc/output.c               |    2 +-
 net/rxrpc/protocol.h             |   20 +
 net/rxrpc/rxgk.c                 | 1170 ++++++++++++++++++++++++++++++
 net/rxrpc/rxgk_app.c             |  284 ++++++++
 net/rxrpc/rxgk_common.h          |  140 ++++
 net/rxrpc/rxgk_kdf.c             |  287 ++++++++
 net/rxrpc/rxkad.c                |    6 +-
 net/rxrpc/security.c             |    3 +
 37 files changed, 6874 insertions(+), 5 deletions(-)
 create mode 100644 Documentation/crypto/krb5.rst
 create mode 100644 crypto/krb5/Kconfig
 create mode 100644 crypto/krb5/Makefile
 create mode 100644 crypto/krb5/internal.h
 create mode 100644 crypto/krb5/krb5_api.c
 create mode 100644 crypto/krb5/krb5_kdf.c
 create mode 100644 crypto/krb5/rfc3961_simplified.c
 create mode 100644 crypto/krb5/rfc3962_aes.c
 create mode 100644 crypto/krb5/rfc6803_camellia.c
 create mode 100644 crypto/krb5/rfc8009_aes2.c
 create mode 100644 crypto/krb5/selftest.c
 create mode 100644 crypto/krb5/selftest_data.c
 create mode 100644 crypto/krb5enc.c
 create mode 100644 include/crypto/krb5.h
 create mode 100644 net/rxrpc/rxgk.c
 create mode 100644 net/rxrpc/rxgk_app.c
 create mode 100644 net/rxrpc/rxgk_common.h
 create mode 100644 net/rxrpc/rxgk_kdf.c

[RFC PATCH 01/24] crypto/krb5: Add API Documentation

[David Howells]

Add API documentation for the kerberos crypto library.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 Documentation/crypto/index.rst |   1 +
 Documentation/crypto/krb5.rst  | 262 +++++++++++++++++++++++++++++++++
 2 files changed, 263 insertions(+)
 create mode 100644 Documentation/crypto/krb5.rst

diff --git a/Documentation/crypto/index.rst b/Documentation/crypto/index.rst
index 92eec78b5713..100b47d049c0 100644
--- a/Documentation/crypto/index.rst
+++ b/Documentation/crypto/index.rst
@@ -26,3 +26,4 @@ for cryptographic use cases, as well as programming examples.
    api-samples
    descore-readme
    device_drivers/index
+   krb5
diff --git a/Documentation/crypto/krb5.rst b/Documentation/crypto/krb5.rst
new file mode 100644
index 000000000000..beffa0133446
--- /dev/null
+++ b/Documentation/crypto/krb5.rst
@@ -0,0 +1,262 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===========================
+Kerberos V Cryptography API
+===========================
+
+.. Contents:
+
+  - Overview.
+    - Small Buffer.
+  - Encoding Type.
+  - Key Derivation.
+    - PRF+ Calculation.
+    - Kc, Ke And Ki Derivation.
+  - Crypto Functions.
+    - Preparation Functions.
+    - Encryption Mode.
+    - Checksum Mode.
+  - The krb5enc AEAD algorithm
+
+Overview
+========
+
+This API provides Kerberos 5-style cryptography for key derivation, encryption
+and checksumming for use in network filesystems and can be used to implement
+the low-level crypto that's needed for GSSAPI.
+
+The following crypto types are supported::
+
+	KRB5_ENCTYPE_AES128_CTS_HMAC_SHA1_96
+	KRB5_ENCTYPE_AES256_CTS_HMAC_SHA1_96
+	KRB5_ENCTYPE_AES128_CTS_HMAC_SHA256_128
+	KRB5_ENCTYPE_AES256_CTS_HMAC_SHA384_192
+	KRB5_ENCTYPE_CAMELLIA128_CTS_CMAC
+	KRB5_ENCTYPE_CAMELLIA256_CTS_CMAC
+
+	KRB5_CKSUMTYPE_HMAC_SHA1_96_AES128
+	KRB5_CKSUMTYPE_HMAC_SHA1_96_AES256
+	KRB5_CKSUMTYPE_CMAC_CAMELLIA128
+	KRB5_CKSUMTYPE_CMAC_CAMELLIA256
+	KRB5_CKSUMTYPE_HMAC_SHA256_128_AES128
+	KRB5_CKSUMTYPE_HMAC_SHA384_192_AES256
+
+The API can be included by::
+
+	#include <crypto/krb5.h>
+
+Small Buffer
+------------
+
+To pass small pieces of data about, such as keys, a buffer structure is
+defined, giving a pointer to the data and the size of that data::
+
+	struct krb5_buffer {
+		unsigned int	len;
+		void		*data;
+	};
+
+Encoding Type
+=============
+
+The encoding type is defined by the following structure::
+
+	struct krb5_enctype {
+		int		etype;
+		int		ctype;
+		const char	*name;
+		u16		key_bytes;
+		u16		key_len;
+		u16		Kc_len;
+		u16		Ke_len;
+		u16		Ki_len;
+		u16		prf_len;
+		u16		block_len;
+		u16		conf_len;
+		u16		cksum_len;
+		...
+	};
+
+The fields of interest to the user of the API are as follows:
+
+  * ``etype`` and ``ctype`` indicate the protocol number for this encoding
+    type for encryption and checksumming respectively.  They hold
+    ``KRB5_ENCTYPE_*`` and ``KRB5_CKSUMTYPE_*`` constants.
+
+  * ``name`` is the formal name of the encoding.
+
+  * ``key_len`` and ``key_bytes`` are the input key length and the derived key
+    length.  (I think they only differ for DES, which isn't supported here).
+
+  * ``Kc_len``, ``Ke_len`` and ``Ki_len`` are the sizes of the derived Kc, Ke
+    and Ki keys.  Kc is used for in checksum mode; Ke and Ki are used in
+    encryption mode.
+
+  * ``prf_len`` is the size of the result from the PRF+ function calculation.
+
+  * ``block_len``, ``conf_len`` and ``cksum_len`` are the encryption block
+    length, confounder length and checksum length respectively.  All three are
+    used in encryption mode, but only the checksum length is used in checksum
+    mode.
+
+The encoding type is looked up by number using the following function::
+
+	const struct krb5_enctype *crypto_krb5_find_enctype(u32 enctype);
+
+Key Derivation
+==============
+
+Once the application has selected an encryption type, the keys that will be
+used to do the actual crypto can be derived from the transport key.
+
+PRF+ Calculation
+----------------
+
+To aid in key derivation, a function to calculate the Kerberos GSSAPI
+mechanism's PRF+ is provided::
+
+	int crypto_krb5_calc_PRFplus(const struct krb5_enctype *krb5,
+				     const struct krb5_buffer *K,
+				     unsigned int L,
+				     const struct krb5_buffer *S,
+				     struct krb5_buffer *result,
+				     gfp_t gfp);
+
+This can be used to derive the transport key from a source key plus additional
+data to limit its use.
+
+Crypto Functions
+================
+
+Once the keys have been derived, crypto can be performed on the data.  The
+caller must leave gaps in the buffer for the storage of the confounder (if
+needed) and the checksum when preparing a message for transmission.  An enum
+and a pair of functions are provided to aid in this::
+
+	enum krb5_crypto_mode {
+		KRB5_CHECKSUM_MODE,
+		KRB5_ENCRYPT_MODE,
+	};
+
+	size_t crypto_krb5_how_much_buffer(const struct krb5_enctype *krb5,
+					   enum krb5_crypto_mode mode,
+					   size_t data_size, size_t *_offset);
+
+	size_t crypto_krb5_how_much_data(const struct krb5_enctype *krb5,
+					 enum krb5_crypto_mode mode,
+					 size_t *_buffer_size, size_t *_offset);
+
+All these functions take the encoding type and an indication the mode of crypto
+(checksum-only or full encryption).
+
+The first function returns how big the buffer will need to be to house a given
+amount of data; the second function returns how much data will fit in a buffer
+of a particular size, and adjusts down the size of the required buffer
+accordingly.  In both cases, the offset of the data within the buffer is also
+returned.
+
+When a message has been received, the location and size of the data with the
+message can be determined by calling::
+
+	void crypto_krb5_where_is_the_data(const struct krb5_enctype *krb5,
+					   enum krb5_crypto_mode mode,
+					   size_t *_offset, size_t *_len);
+
+The caller provides the offset and length of the message to the function, which
+then alters those values to indicate the region containing the data (plus any
+padding).  It is up to the caller to determine how much padding there is.
+
+Preparation Functions
+---------------------
+
+Two functions are provided to allocated and prepare a crypto object for use by
+the action functions::
+
+	struct crypto_aead *
+	crypto_krb5_prepare_encryption(const struct krb5_enctype *krb5,
+				       const struct krb5_buffer *TK,
+				       u32 usage, gfp_t gfp);
+	struct crypto_shash *
+	crypto_krb5_prepare_checksum(const struct krb5_enctype *krb5,
+				     const struct krb5_buffer *TK,
+				     u32 usage, gfp_t gfp);
+
+Both of these functions take the encoding type, the transport key and the usage
+value used to derive the appropriate subkey(s).  They create an appropriate
+crypto object, an AEAD template for encryption and a synchronous hash for
+checksumming, set the key(s) on it and configure it.  The caller is expected to
+pass these handles to the action functions below.
+
+Encryption Mode
+---------------
+
+A pair of functions are provided to encrypt and decrypt a message::
+
+	ssize_t crypto_krb5_encrypt(const struct krb5_enctype *krb5,
+				    struct crypto_aead *aead,
+				    struct scatterlist *sg, unsigned int nr_sg,
+				    size_t sg_len,
+				    size_t data_offset, size_t data_len,
+				    bool preconfounded);
+	int crypto_krb5_decrypt(const struct krb5_enctype *krb5,
+				struct crypto_aead *aead,
+				struct scatterlist *sg, unsigned int nr_sg,
+				size_t *_offset, size_t *_len);
+
+In both cases, the input and output buffers are indicated by the same
+scatterlist.
+
+For the encryption function, the output buffer may be larger than is needed
+(the amount of output generated is returned) and the location and size of the
+data are indicated (which must match the encoding).  If no confounder is set,
+the function will insert one.
+
+For the decryption function, the offset and length of the message in buffer are
+supplied and these are shrunk to fit the data.  The decryption function will
+verify any checksums within the message and give an error if they don't match.
+
+Checksum Mode
+-------------
+
+A pair of function are provided to generate the checksum on a message and to
+verify that checksum::
+
+	ssize_t crypto_krb5_get_mic(const struct krb5_enctype *krb5,
+				    struct crypto_shash *shash,
+				    const struct krb5_buffer *metadata,
+				    struct scatterlist *sg, unsigned int nr_sg,
+				    size_t sg_len,
+				    size_t data_offset, size_t data_len);
+	int crypto_krb5_verify_mic(const struct krb5_enctype *krb5,
+				   struct crypto_shash *shash,
+				   const struct krb5_buffer *metadata,
+				   struct scatterlist *sg, unsigned int nr_sg,
+				   size_t *_offset, size_t *_len);
+
+In both cases, the input and output buffers are indicated by the same
+scatterlist.  Additional metadata can be passed in which will get added to the
+hash before the data.
+
+For the get_mic function, the output buffer may be larger than is needed (the
+amount of output generated is returned) and the location and size of the data
+are indicated (which must match the encoding).
+
+For the verification function, the offset and length of the message in buffer
+are supplied and these are shrunk to fit the data.  An error will be returned
+if the checksums don't match.
+
+The krb5enc AEAD algorithm
+==========================
+
+A template AEAD crypto algorithm, called "krb5enc", is provided that hashes the
+plaintext before encrypting it (the reverse of authenc).  The handle returned
+by ``crypto_krb5_prepare_encryption()`` may be one of these, but there's no
+requirement for the user of this API to interact with it directly.
+
+For reference, its key format begins with a BE32 of the format number.  Only
+format 1 is provided and that continues with a BE32 of the Ke key length
+followed by a BE32 of the Ki key length, followed by the bytes from the Ke key
+and then the Ki key.
+
+Using specifically ordered words means that the static test data doesn't
+require byteswapping.

[RFC PATCH 02/24] crypto/krb5: Add some constants out of sunrpc headers

[David Howells]

Add some constants from the sunrpc headers.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 include/crypto/krb5.h | 51 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)
 create mode 100644 include/crypto/krb5.h

diff --git a/include/crypto/krb5.h b/include/crypto/krb5.h
new file mode 100644
index 000000000000..44a6342471d7
--- /dev/null
+++ b/include/crypto/krb5.h
@@ -0,0 +1,51 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* Kerberos 5 crypto
+ *
+ * Copyright (C) 2025 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#ifndef _CRYPTO_KRB5_H
+#define _CRYPTO_KRB5_H
+
+/*
+ * Per Kerberos v5 protocol spec crypto types from the wire.  These get mapped
+ * to linux kernel crypto routines.
+ */
+#define KRB5_ENCTYPE_NULL			0x0000
+#define KRB5_ENCTYPE_DES_CBC_CRC		0x0001	/* DES cbc mode with CRC-32 */
+#define KRB5_ENCTYPE_DES_CBC_MD4		0x0002	/* DES cbc mode with RSA-MD4 */
+#define KRB5_ENCTYPE_DES_CBC_MD5		0x0003	/* DES cbc mode with RSA-MD5 */
+#define KRB5_ENCTYPE_DES_CBC_RAW		0x0004	/* DES cbc mode raw */
+/* XXX deprecated? */
+#define KRB5_ENCTYPE_DES3_CBC_SHA		0x0005	/* DES-3 cbc mode with NIST-SHA */
+#define KRB5_ENCTYPE_DES3_CBC_RAW		0x0006	/* DES-3 cbc mode raw */
+#define KRB5_ENCTYPE_DES_HMAC_SHA1		0x0008
+#define KRB5_ENCTYPE_DES3_CBC_SHA1		0x0010
+#define KRB5_ENCTYPE_AES128_CTS_HMAC_SHA1_96	0x0011
+#define KRB5_ENCTYPE_AES256_CTS_HMAC_SHA1_96	0x0012
+#define KRB5_ENCTYPE_ARCFOUR_HMAC		0x0017
+#define KRB5_ENCTYPE_ARCFOUR_HMAC_EXP		0x0018
+#define KRB5_ENCTYPE_UNKNOWN			0x01ff
+
+#define KRB5_CKSUMTYPE_CRC32			0x0001
+#define KRB5_CKSUMTYPE_RSA_MD4			0x0002
+#define KRB5_CKSUMTYPE_RSA_MD4_DES		0x0003
+#define KRB5_CKSUMTYPE_DESCBC			0x0004
+#define KRB5_CKSUMTYPE_RSA_MD5			0x0007
+#define KRB5_CKSUMTYPE_RSA_MD5_DES		0x0008
+#define KRB5_CKSUMTYPE_NIST_SHA			0x0009
+#define KRB5_CKSUMTYPE_HMAC_SHA1_DES3		0x000c
+#define KRB5_CKSUMTYPE_HMAC_SHA1_96_AES128	0x000f
+#define KRB5_CKSUMTYPE_HMAC_SHA1_96_AES256	0x0010
+#define KRB5_CKSUMTYPE_HMAC_MD5_ARCFOUR		-138 /* Microsoft md5 hmac cksumtype */
+
+/*
+ * Constants used for key derivation
+ */
+/* from rfc3961 */
+#define KEY_USAGE_SEED_CHECKSUM         (0x99)
+#define KEY_USAGE_SEED_ENCRYPTION       (0xAA)
+#define KEY_USAGE_SEED_INTEGRITY        (0x55)
+
+#endif /* _CRYPTO_KRB5_H */

[RFC PATCH 03/24] crypto: Add 'krb5enc' hash and cipher AEAD algorithm

[David Howells]

Add an AEAD template that does hash-then-cipher (unlike authenc that does
cipher-then-hash).  This is required for a number of Kerberos 5 encoding
types.

[!] Note that the net/sunrpc/auth_gss/ implementation gets a pair of
ciphers, one non-CTS and one CTS, using the former to do all the aligned
blocks and the latter to do the last two blocks if they aren't also
aligned.  It may be necessary to do this here too for performance reasons -
but there are considerations both ways:

 (1) firstly, there is an optimised assembly version of cts(cbc(aes)) on
     x86_64 that should be used instead of having two ciphers;

 (2) secondly, none of the hardware offload drivers seem to offer CTS
     support (Intel QAT does not, for instance).

However, I don't know if it's possible to query the crypto API to find out
whether there's an optimised CTS algorithm available.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/Kconfig        |  12 ++
 crypto/Makefile       |   1 +
 crypto/krb5enc.c      | 491 ++++++++++++++++++++++++++++++++++++++++++
 include/crypto/krb5.h |   7 +
 4 files changed, 511 insertions(+)
 create mode 100644 crypto/krb5enc.c

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 6b0bfbccac08..18b1a3b3a258 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -228,6 +228,18 @@ config CRYPTO_AUTHENC
 
 	  This is required for IPSec ESP (XFRM_ESP).
 
+config CRYPTO_KRB5ENC
+	tristate "Kerberos 5 combined hash+cipher support"
+	select CRYPTO_AEAD
+	select CRYPTO_SKCIPHER
+	select CRYPTO_MANAGER
+	select CRYPTO_HASH
+	select CRYPTO_NULL
+	help
+	  Combined hash and cipher support for Kerberos 5 RFC3961 simplified
+	  profile.  This is required for Kerberos 5-style encryption, used by
+	  sunrpc/NFS and rxrpc/AFS.
+
 config CRYPTO_TEST
 	tristate "Testing module"
 	depends on m || EXPERT
diff --git a/crypto/Makefile b/crypto/Makefile
index 77abca715445..eb40638c6c04 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -160,6 +160,7 @@ CFLAGS_crc32_generic.o += -DARCH=$(ARCH)
 obj-$(CONFIG_CRYPTO_CRCT10DIF) += crct10dif_common.o crct10dif_generic.o
 obj-$(CONFIG_CRYPTO_CRC64_ROCKSOFT) += crc64_rocksoft_generic.o
 obj-$(CONFIG_CRYPTO_AUTHENC) += authenc.o authencesn.o
+obj-$(CONFIG_CRYPTO_KRB5ENC) += krb5enc.o
 obj-$(CONFIG_CRYPTO_LZO) += lzo.o lzo-rle.o
 obj-$(CONFIG_CRYPTO_LZ4) += lz4.o
 obj-$(CONFIG_CRYPTO_LZ4HC) += lz4hc.o
diff --git a/crypto/krb5enc.c b/crypto/krb5enc.c
new file mode 100644
index 000000000000..931387a8ee6f
--- /dev/null
+++ b/crypto/krb5enc.c
@@ -0,0 +1,491 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * AEAD wrapper for Kerberos 5 RFC3961 simplified profile.
+ *
+ * Copyright (C) 2025 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * Derived from authenc:
+ * Copyright (c) 2007-2015 Herbert Xu <herbert@gondor.apana.org.au>
+ */
+
+#include <crypto/internal/aead.h>
+#include <crypto/internal/hash.h>
+#include <crypto/internal/skcipher.h>
+#include <crypto/krb5.h>
+#include <crypto/authenc.h>
+#include <crypto/scatterwalk.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/rtnetlink.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+struct krb5enc_instance_ctx {
+	struct crypto_ahash_spawn auth;
+	struct crypto_skcipher_spawn enc;
+	unsigned int reqoff;
+};
+
+struct krb5enc_ctx {
+	struct crypto_ahash *auth;
+	struct crypto_skcipher *enc;
+};
+
+struct krb5enc_request_ctx {
+	struct scatterlist src[2];
+	struct scatterlist dst[2];
+	char tail[];
+};
+
+static void krb5enc_request_complete(struct aead_request *req, int err)
+{
+	if (err != -EINPROGRESS)
+		aead_request_complete(req, err);
+}
+
+/**
+ * crypto_krb5enc_extractkeys - Extract Ke and Ki keys from the key blob.
+ * @keys: Where to put the key sizes and pointers
+ * @key: Encoded key material
+ * @keylen: Amount of key material
+ *
+ * Decode the key blob we're given.  It starts with a __be32 that indicates the
+ * format.  Format 1 is:
+ *
+ *  be32 1 || be32 Ke len || be32 Ki len || Ke || Ki
+ */
+int crypto_krb5enc_extractkeys(struct crypto_authenc_keys *keys, const u8 *key,
+			       unsigned int keylen)
+{
+	__be32 *k = (void *)key;
+	u32 format, Ke_len, Ki_len;
+
+	if (keylen < 16)
+		return -EINVAL;
+
+	format = get_unaligned_be32(k++);
+	if (format != 1)
+		return -EINVAL;
+	Ke_len = get_unaligned_be32(k++);
+	Ki_len = get_unaligned_be32(k++);
+	keylen -= 12;
+
+	if (Ke_len + Ki_len != keylen)
+		return -EINVAL;
+
+	keys->enckeylen		= Ke_len;
+	keys->enckey		= (void *)k;
+	keys->authkeylen	= Ki_len;
+	keys->authkey		= (void *)k + Ke_len;
+	return 0;
+}
+EXPORT_SYMBOL(crypto_krb5enc_extractkeys);
+
+static int krb5enc_setkey(struct crypto_aead *krb5enc, const u8 *key,
+			  unsigned int keylen)
+{
+	struct crypto_authenc_keys keys;
+	struct krb5enc_ctx *ctx = crypto_aead_ctx(krb5enc);
+	struct crypto_skcipher *enc = ctx->enc;
+	struct crypto_ahash *auth = ctx->auth;
+	unsigned int flags = crypto_aead_get_flags(krb5enc);
+	int err = -EINVAL;
+
+	if (crypto_krb5enc_extractkeys(&keys, key, keylen) != 0)
+		goto out;
+
+	crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
+	crypto_ahash_set_flags(auth, flags & CRYPTO_TFM_REQ_MASK);
+	err = crypto_ahash_setkey(auth, keys.authkey, keys.authkeylen);
+	if (err)
+		goto out;
+
+	crypto_skcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
+	crypto_skcipher_set_flags(enc, flags & CRYPTO_TFM_REQ_MASK);
+	err = crypto_skcipher_setkey(enc, keys.enckey, keys.enckeylen);
+out:
+	memzero_explicit(&keys, sizeof(keys));
+	return err;
+}
+
+static void krb5enc_encrypt_done(void *data, int err)
+{
+	struct aead_request *req = data;
+
+	krb5enc_request_complete(req, err);
+}
+
+/*
+ * Start the encryption of the plaintext.  We skip over the associated data as
+ * that only gets included in the hash.
+ */
+static int krb5enc_dispatch_encrypt(struct aead_request *req,
+				    unsigned int flags)
+{
+	struct crypto_aead *krb5enc = crypto_aead_reqtfm(req);
+	struct aead_instance *inst = aead_alg_instance(krb5enc);
+	struct krb5enc_ctx *ctx = crypto_aead_ctx(krb5enc);
+	struct krb5enc_instance_ctx *ictx = aead_instance_ctx(inst);
+	struct krb5enc_request_ctx *areq_ctx = aead_request_ctx(req);
+	struct crypto_skcipher *enc = ctx->enc;
+	struct skcipher_request *skreq = (void *)(areq_ctx->tail +
+						  ictx->reqoff);
+	struct scatterlist *src, *dst;
+
+	src = scatterwalk_ffwd(areq_ctx->src, req->src, req->assoclen);
+	if (req->src == req->dst)
+		dst = src;
+	else
+		dst = scatterwalk_ffwd(areq_ctx->dst, req->dst, req->assoclen);
+
+	skcipher_request_set_tfm(skreq, enc);
+	skcipher_request_set_callback(skreq, aead_request_flags(req),
+				      krb5enc_encrypt_done, req);
+	skcipher_request_set_crypt(skreq, src, dst, req->cryptlen, req->iv);
+
+	return crypto_skcipher_encrypt(skreq);
+}
+
+/*
+ * Insert the hash into the checksum field in the destination buffer directly
+ * after the encrypted region.
+ */
+static void krb5enc_insert_checksum(struct aead_request *req, u8 *hash)
+{
+	struct crypto_aead *krb5enc = crypto_aead_reqtfm(req);
+
+	scatterwalk_map_and_copy(hash, req->dst,
+				 req->assoclen + req->cryptlen,
+				 crypto_aead_authsize(krb5enc), 1);
+}
+
+/*
+ * Upon completion of an asynchronous digest, transfer the hash to the checksum
+ * field.
+ */
+static void krb5enc_encrypt_ahash_done(void *data, int err)
+{
+	struct aead_request *req = data;
+	struct crypto_aead *krb5enc = crypto_aead_reqtfm(req);
+	struct aead_instance *inst = aead_alg_instance(krb5enc);
+	struct krb5enc_instance_ctx *ictx = aead_instance_ctx(inst);
+	struct krb5enc_request_ctx *areq_ctx = aead_request_ctx(req);
+	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ictx->reqoff);
+
+	if (err)
+		return krb5enc_request_complete(req, err);
+
+	krb5enc_insert_checksum(req, ahreq->result);
+
+	err = krb5enc_dispatch_encrypt(req, 0);
+	if (err != -EINPROGRESS)
+		aead_request_complete(req, err);
+}
+
+/*
+ * Start the digest of the plaintext for encryption.  In theory, this could be
+ * run in parallel with the encryption, provided the src and dst buffers don't
+ * overlap.
+ */
+static int krb5enc_dispatch_encrypt_hash(struct aead_request *req)
+{
+	struct crypto_aead *krb5enc = crypto_aead_reqtfm(req);
+	struct aead_instance *inst = aead_alg_instance(krb5enc);
+	struct krb5enc_ctx *ctx = crypto_aead_ctx(krb5enc);
+	struct krb5enc_instance_ctx *ictx = aead_instance_ctx(inst);
+	struct crypto_ahash *auth = ctx->auth;
+	struct krb5enc_request_ctx *areq_ctx = aead_request_ctx(req);
+	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ictx->reqoff);
+	u8 *hash = areq_ctx->tail;
+	int err;
+
+	ahash_request_set_callback(ahreq, aead_request_flags(req),
+				   krb5enc_encrypt_ahash_done, req);
+	ahash_request_set_tfm(ahreq, auth);
+	ahash_request_set_crypt(ahreq, req->src, hash, req->assoclen + req->cryptlen);
+
+	err = crypto_ahash_digest(ahreq);
+	if (err)
+		return err;
+
+	krb5enc_insert_checksum(req, hash);
+	return 0;
+}
+
+/*
+ * Process an encryption operation.  We can perform the cipher and the hash in
+ * parallel, provided the src and dst buffers are separate.
+ */
+static int krb5enc_encrypt(struct aead_request *req)
+{
+	int err;
+
+	err = krb5enc_dispatch_encrypt_hash(req);
+	if (err < 0)
+		return err;
+
+	return krb5enc_dispatch_encrypt(req, aead_request_flags(req));
+}
+
+static int krb5enc_verify_hash(struct aead_request *req, void *hash)
+{
+	struct crypto_aead *krb5enc = crypto_aead_reqtfm(req);
+	struct aead_instance *inst = aead_alg_instance(krb5enc);
+	struct krb5enc_instance_ctx *ictx = aead_instance_ctx(inst);
+	struct krb5enc_request_ctx *areq_ctx = aead_request_ctx(req);
+	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ictx->reqoff);
+	unsigned int authsize = crypto_aead_authsize(krb5enc);
+	u8 *ihash = ahreq->result + authsize;
+
+	scatterwalk_map_and_copy(ihash, req->src, ahreq->nbytes, authsize, 0);
+
+	if (crypto_memneq(ihash, ahreq->result, authsize))
+		return -EBADMSG;
+	return 0;
+}
+
+static void krb5enc_decrypt_hash_done(void *data, int err)
+{
+	struct aead_request *req = data;
+
+	if (err)
+		return krb5enc_request_complete(req, err);
+
+	err = krb5enc_verify_hash(req, 0);
+	krb5enc_request_complete(req, err);
+}
+
+/*
+ * Dispatch the hashing of the plaintext after we've done the decryption.
+ */
+static int krb5enc_dispatch_decrypt_hash(struct aead_request *req)
+{
+	struct crypto_aead *krb5enc = crypto_aead_reqtfm(req);
+	struct aead_instance *inst = aead_alg_instance(krb5enc);
+	struct krb5enc_ctx *ctx = crypto_aead_ctx(krb5enc);
+	struct krb5enc_instance_ctx *ictx = aead_instance_ctx(inst);
+	struct krb5enc_request_ctx *areq_ctx = aead_request_ctx(req);
+	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ictx->reqoff);
+	struct crypto_ahash *auth = ctx->auth;
+	unsigned int authsize = crypto_aead_authsize(krb5enc);
+	u8 *hash = areq_ctx->tail;
+	int err;
+
+	ahash_request_set_tfm(ahreq, auth);
+	ahash_request_set_crypt(ahreq, req->dst, hash,
+				req->assoclen + req->cryptlen - authsize);
+	ahash_request_set_callback(ahreq, aead_request_flags(req),
+				   krb5enc_decrypt_hash_done, req);
+
+	err = crypto_ahash_digest(ahreq);
+	if (err < 0)
+		return err;
+
+	return krb5enc_verify_hash(req, hash);
+}
+
+/*
+ * Dispatch the decryption of the ciphertext.
+ */
+static int krb5enc_dispatch_decrypt(struct aead_request *req)
+{
+	struct crypto_aead *krb5enc = crypto_aead_reqtfm(req);
+	struct aead_instance *inst = aead_alg_instance(krb5enc);
+	struct krb5enc_ctx *ctx = crypto_aead_ctx(krb5enc);
+	struct krb5enc_instance_ctx *ictx = aead_instance_ctx(inst);
+	struct krb5enc_request_ctx *areq_ctx = aead_request_ctx(req);
+	struct skcipher_request *skreq = (void *)(areq_ctx->tail +
+						  ictx->reqoff);
+	unsigned int authsize = crypto_aead_authsize(krb5enc);
+	struct scatterlist *src, *dst;
+
+	src = scatterwalk_ffwd(areq_ctx->src, req->src, req->assoclen);
+	dst = src;
+
+	if (req->src != req->dst)
+		dst = scatterwalk_ffwd(areq_ctx->dst, req->dst, req->assoclen);
+
+	skcipher_request_set_tfm(skreq, ctx->enc);
+	skcipher_request_set_callback(skreq, aead_request_flags(req),
+				      req->base.complete, req->base.data);
+	skcipher_request_set_crypt(skreq, src, dst,
+				   req->cryptlen - authsize, req->iv);
+
+	return crypto_skcipher_decrypt(skreq);
+}
+
+static int krb5enc_decrypt(struct aead_request *req)
+{
+	int err;
+
+	err = krb5enc_dispatch_decrypt(req);
+	if (err < 0)
+		return err;
+
+	return krb5enc_dispatch_decrypt_hash(req);
+}
+
+static int krb5enc_init_tfm(struct crypto_aead *tfm)
+{
+	struct aead_instance *inst = aead_alg_instance(tfm);
+	struct krb5enc_instance_ctx *ictx = aead_instance_ctx(inst);
+	struct krb5enc_ctx *ctx = crypto_aead_ctx(tfm);
+	struct crypto_ahash *auth;
+	struct crypto_skcipher *enc;
+	int err;
+
+	auth = crypto_spawn_ahash(&ictx->auth);
+	if (IS_ERR(auth))
+		return PTR_ERR(auth);
+
+	enc = crypto_spawn_skcipher(&ictx->enc);
+	err = PTR_ERR(enc);
+	if (IS_ERR(enc))
+		goto err_free_ahash;
+
+	ctx->auth = auth;
+	ctx->enc = enc;
+
+	crypto_aead_set_reqsize(
+		tfm,
+		sizeof(struct krb5enc_request_ctx) +
+		ictx->reqoff +
+		umax(sizeof(struct ahash_request) + crypto_ahash_reqsize(auth),
+		     sizeof(struct skcipher_request) + crypto_skcipher_reqsize(enc)));
+
+	return 0;
+
+err_free_ahash:
+	crypto_free_ahash(auth);
+	return err;
+}
+
+static void krb5enc_exit_tfm(struct crypto_aead *tfm)
+{
+	struct krb5enc_ctx *ctx = crypto_aead_ctx(tfm);
+
+	crypto_free_ahash(ctx->auth);
+	crypto_free_skcipher(ctx->enc);
+}
+
+static void krb5enc_free(struct aead_instance *inst)
+{
+	struct krb5enc_instance_ctx *ctx = aead_instance_ctx(inst);
+
+	crypto_drop_skcipher(&ctx->enc);
+	crypto_drop_ahash(&ctx->auth);
+	kfree(inst);
+}
+
+/*
+ * Create an instance of a template for a specific hash and cipher pair.
+ */
+static int krb5enc_create(struct crypto_template *tmpl, struct rtattr **tb)
+{
+	struct krb5enc_instance_ctx *ictx;
+	struct skcipher_alg_common *enc;
+	struct hash_alg_common *auth;
+	struct aead_instance *inst;
+	struct crypto_alg *auth_base;
+	u32 mask;
+	int err;
+
+	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask);
+	if (err) {
+		pr_err("attr_type failed\n");
+		return err;
+	}
+
+	inst = kzalloc(sizeof(*inst) + sizeof(*ictx), GFP_KERNEL);
+	if (!inst)
+		return -ENOMEM;
+	ictx = aead_instance_ctx(inst);
+
+	err = crypto_grab_ahash(&ictx->auth, aead_crypto_instance(inst),
+				crypto_attr_alg_name(tb[1]), 0, mask);
+	if (err) {
+		pr_err("grab ahash failed\n");
+		goto err_free_inst;
+	}
+	auth = crypto_spawn_ahash_alg(&ictx->auth);
+	auth_base = &auth->base;
+
+	err = crypto_grab_skcipher(&ictx->enc, aead_crypto_instance(inst),
+				   crypto_attr_alg_name(tb[2]), 0, mask);
+	if (err) {
+		pr_err("grab skcipher failed\n");
+		goto err_free_inst;
+	}
+	enc = crypto_spawn_skcipher_alg_common(&ictx->enc);
+
+	ictx->reqoff = 2 * auth->digestsize;
+
+	err = -ENAMETOOLONG;
+	if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
+		     "krb5enc(%s,%s)", auth_base->cra_name,
+		     enc->base.cra_name) >=
+	    CRYPTO_MAX_ALG_NAME)
+		goto err_free_inst;
+
+	if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
+		     "krb5enc(%s,%s)", auth_base->cra_driver_name,
+		     enc->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
+		goto err_free_inst;
+
+	inst->alg.base.cra_priority = enc->base.cra_priority * 10 +
+				      auth_base->cra_priority;
+	inst->alg.base.cra_blocksize = enc->base.cra_blocksize;
+	inst->alg.base.cra_alignmask = enc->base.cra_alignmask;
+	inst->alg.base.cra_ctxsize = sizeof(struct krb5enc_ctx);
+
+	inst->alg.ivsize = enc->ivsize;
+	inst->alg.chunksize = enc->chunksize;
+	inst->alg.maxauthsize = auth->digestsize;
+
+	inst->alg.init = krb5enc_init_tfm;
+	inst->alg.exit = krb5enc_exit_tfm;
+
+	inst->alg.setkey = krb5enc_setkey;
+	inst->alg.encrypt = krb5enc_encrypt;
+	inst->alg.decrypt = krb5enc_decrypt;
+
+	inst->free = krb5enc_free;
+
+	err = aead_register_instance(tmpl, inst);
+	if (err) {
+		pr_err("ref failed\n");
+		goto err_free_inst;
+	}
+
+	return 0;
+
+err_free_inst:
+	krb5enc_free(inst);
+	return err;
+}
+
+static struct crypto_template crypto_krb5enc_tmpl = {
+	.name = "krb5enc",
+	.create = krb5enc_create,
+	.module = THIS_MODULE,
+};
+
+static int __init crypto_krb5enc_module_init(void)
+{
+	return crypto_register_template(&crypto_krb5enc_tmpl);
+}
+
+static void __exit crypto_krb5enc_module_exit(void)
+{
+	crypto_unregister_template(&crypto_krb5enc_tmpl);
+}
+
+subsys_initcall(crypto_krb5enc_module_init);
+module_exit(crypto_krb5enc_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Simple AEAD wrapper for Kerberos 5 RFC3961");
+MODULE_ALIAS_CRYPTO("krb5enc");
diff --git a/include/crypto/krb5.h b/include/crypto/krb5.h
index 44a6342471d7..8949a9b71de3 100644
--- a/include/crypto/krb5.h
+++ b/include/crypto/krb5.h
@@ -48,4 +48,11 @@
 #define KEY_USAGE_SEED_ENCRYPTION       (0xAA)
 #define KEY_USAGE_SEED_INTEGRITY        (0x55)
 
+/*
+ * krb5enc.c
+ */
+struct crypto_authenc_keys;
+int crypto_krb5enc_extractkeys(struct crypto_authenc_keys *keys, const u8 *key,
+			       unsigned int keylen);
+
 #endif /* _CRYPTO_KRB5_H */

Re: [RFC PATCH 03/24] crypto: Add 'krb5enc' hash and cipher AEAD algorithm

[Simon Horman]

On Fri, Jan 17, 2025 at 06:35:12PM +0000, David Howells wrote:
> Add an AEAD template that does hash-then-cipher (unlike authenc that does
> cipher-then-hash).  This is required for a number of Kerberos 5 encoding
> types.
> 
> [!] Note that the net/sunrpc/auth_gss/ implementation gets a pair of
> ciphers, one non-CTS and one CTS, using the former to do all the aligned
> blocks and the latter to do the last two blocks if they aren't also
> aligned.  It may be necessary to do this here too for performance reasons -
> but there are considerations both ways:
> 
>  (1) firstly, there is an optimised assembly version of cts(cbc(aes)) on
>      x86_64 that should be used instead of having two ciphers;
> 
>  (2) secondly, none of the hardware offload drivers seem to offer CTS
>      support (Intel QAT does not, for instance).
> 
> However, I don't know if it's possible to query the crypto API to find out
> whether there's an optimised CTS algorithm available.
> 
> Signed-off-by: David Howells <dhowells@redhat.com>

...

> diff --git a/crypto/krb5enc.c b/crypto/krb5enc.c

...

> +static int krb5enc_verify_hash(struct aead_request *req, void *hash)
> +{
> +	struct crypto_aead *krb5enc = crypto_aead_reqtfm(req);
> +	struct aead_instance *inst = aead_alg_instance(krb5enc);
> +	struct krb5enc_instance_ctx *ictx = aead_instance_ctx(inst);
> +	struct krb5enc_request_ctx *areq_ctx = aead_request_ctx(req);
> +	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ictx->reqoff);
> +	unsigned int authsize = crypto_aead_authsize(krb5enc);
> +	u8 *ihash = ahreq->result + authsize;
> +
> +	scatterwalk_map_and_copy(ihash, req->src, ahreq->nbytes, authsize, 0);
> +
> +	if (crypto_memneq(ihash, ahreq->result, authsize))
> +		return -EBADMSG;
> +	return 0;
> +}
> +
> +static void krb5enc_decrypt_hash_done(void *data, int err)
> +{
> +	struct aead_request *req = data;
> +
> +	if (err)
> +		return krb5enc_request_complete(req, err);
> +
> +	err = krb5enc_verify_hash(req, 0);

Hi David,

Sparse complains that the second argument to krb5enc_verify_hash should be
a pointer rather than an integer. So perhaps this would be slightly better
expressed as (completely untested!):

	err = krb5enc_verify_hash(req, NULL);

> +	krb5enc_request_complete(req, err);

...
> +}

Re: [RFC PATCH 03/24] crypto: Add 'krb5enc' hash and cipher AEAD algorithm

[David Howells]

Simon Horman <horms@kernel.org> wrote:

> > +static void krb5enc_decrypt_hash_done(void *data, int err)
> > +{
> > +	struct aead_request *req = data;
> > +
> > +	if (err)
> > +		return krb5enc_request_complete(req, err);
> > +
> > +	err = krb5enc_verify_hash(req, 0);
> 
> Hi David,
> 
> Sparse complains that the second argument to krb5enc_verify_hash should be
> a pointer rather than an integer. So perhaps this would be slightly better
> expressed as (completely untested!):
> 
> 	err = krb5enc_verify_hash(req, NULL);

Actually, no.  It should be "ahreq->result + authsize" and
krb5enc_verify_hash() shouldn't calculate ihash, but use its hash parameter.

I wonder if the testmgr driver tests running the algorithms asynchronously...

Thanks,
David

Re: [RFC PATCH 03/24] crypto: Add 'krb5enc' hash and cipher AEAD algorithm

[Eric Biggers]

On Mon, Jan 20, 2025 at 02:25:11PM +0000, David Howells wrote:
> 
> I wonder if the testmgr driver tests running the algorithms asynchronously...
> 

Multiple requests in parallel, I think you mean?  No, it doesn't, but it should.

- Eric

Re: [RFC PATCH 03/24] crypto: Add 'krb5enc' hash and cipher AEAD algorithm

[David Howells]

Eric Biggers <ebiggers@kernel.org> wrote:

> Multiple requests in parallel, I think you mean?  No, it doesn't, but it
> should.

Not so much.  This bug is on the asynchronous path and not tested by my
rxrpc/rxgk code which only exercises the synchronous path.  I haven't tried to
make that asynchronous yet.  I presume testmgr also only tests the sync path.

David

Re: [RFC PATCH 03/24] crypto: Add 'krb5enc' hash and cipher AEAD algorithm

[Eric Biggers]

On Mon, Jan 20, 2025 at 06:59:40PM +0000, David Howells wrote:
> Eric Biggers <ebiggers@kernel.org> wrote:
> 
> > Multiple requests in parallel, I think you mean?  No, it doesn't, but it
> > should.
> 
> Not so much.  This bug is on the asynchronous path and not tested by my
> rxrpc/rxgk code which only exercises the synchronous path.  I haven't tried to
> make that asynchronous yet.  I presume testmgr also only tests the sync path.
> 
> David
> 

I'm not sure I understand your question.  Users of the crypto API can exclude
asynchronous algorithms when selecting one, but the self-tests do not do that.

In any case, why would you need anything to do asynchronous at all here?

- Eric

Re: [RFC PATCH 03/24] crypto: Add 'krb5enc' hash and cipher AEAD algorithm

[David Howells]

Eric Biggers <ebiggers@kernel.org> wrote:

> In any case, why would you need anything to do asynchronous at all here?

Because authenc, which I copied, passes the asynchronocity mode onto the two
algos it runs (one encrypt, one hash).  If authenc is run synchronously, then
the algos are run synchronously and serially; but if authenc is run async,
then the algos are run asynchronously - but they may still have to be run
serially[*] and the second is dispatched from the completion handler of the
first.  So two different paths through the code exist, and rxgk and testmgr
only test the synchronous path.

[*] Because in authenc-compatible encoding types, the output of the encryption
is hashed.  Older krb5 encodings hash the plaintext and the hash generation
and the encrypt can be run in parallel.  For decrypting, the reverse is true;
authenc may be able to do the decrypt and the hash in parallel...  But
parallellisation also requires that the input and output buffers are not the
same.

Anyway.  If it can be done asynchronously, that should probably be tested.

David

Re: [RFC PATCH 03/24] crypto: Add 'krb5enc' hash and cipher AEAD algorithm

[Eric Biggers]

On Mon, Jan 20, 2025 at 08:18:14PM +0000, David Howells wrote:
> Eric Biggers <ebiggers@kernel.org> wrote:
> 
> > In any case, why would you need anything to do asynchronous at all here?
> 
> Because authenc, which I copied, passes the asynchronocity mode onto the two
> algos it runs (one encrypt, one hash).  If authenc is run synchronously, then
> the algos are run synchronously and serially; but if authenc is run async,
> then the algos are run asynchronously - but they may still have to be run
> serially[*] and the second is dispatched from the completion handler of the
> first.  So two different paths through the code exist, and rxgk and testmgr
> only test the synchronous path.

No, it goes in the other direction.  The underlying algorithms decide whether
they are asynchronous or not, and that gets passed up.  It sounds like what you
want to do is test your template in the case where the underlying algorithms are
asynchronous.  There is a way to do that by wrapping the underlying algorithms
with cryptd.  For example the following works with gcm:

python3 <<EOF
import socket
s = socket.socket(socket.AF_ALG, 5, 0)
s.bind(("aead", "gcm_base(cryptd(ctr(aes-generic)),cryptd(ghash-generic))"))
EOF

This really should just be thought of as complying with the outdated design of
the crypto API, though.  In practice synchronous is the only case that really
matters.

> [*] Because in authenc-compatible encoding types, the output of the encryption
> is hashed.  Older krb5 encodings hash the plaintext and the hash generation
> and the encrypt can be run in parallel.  For decrypting, the reverse is true;
> authenc may be able to do the decrypt and the hash in parallel...  But
> parallellisation also requires that the input and output buffers are not the
> same.

The right way to optimize cases like that is to interleave the two computations.
Look at how the AES-GCM assembly code interleaves AES-CTR and GHASH for example.
Doing something with async threads is the completely wrong solution here and
would be much slower.  The amount of time needed to process a single message is
simply far too short for multithreading to be appropriate on a per message
basis.

- Eric

Re: [RFC PATCH 03/24] crypto: Add 'krb5enc' hash and cipher AEAD algorithm

[David Howells]

David Howells <dhowells@redhat.com> wrote:

> > Sparse complains that the second argument to krb5enc_verify_hash should be
> > a pointer rather than an integer. So perhaps this would be slightly better
> > expressed as (completely untested!):
> > 
> > 	err = krb5enc_verify_hash(req, NULL);
> 
> Actually, no.  It should be "ahreq->result + authsize" and
> krb5enc_verify_hash() shouldn't calculate ihash, but use its hash parameter.

Ah.  That's wrong also.  I'm going to drop the second parameter and just
calculate the hash pointers directly.

David
---
diff --git a/crypto/krb5enc.c b/crypto/krb5enc.c
index 931387a8ee6f..e5cec47e7e42 100644
--- a/crypto/krb5enc.c
+++ b/crypto/krb5enc.c
@@ -230,7 +230,7 @@ static int krb5enc_encrypt(struct aead_request *req)
 	return krb5enc_dispatch_encrypt(req, aead_request_flags(req));
 }
 
-static int krb5enc_verify_hash(struct aead_request *req, void *hash)
+static int krb5enc_verify_hash(struct aead_request *req)
 {
 	struct crypto_aead *krb5enc = crypto_aead_reqtfm(req);
 	struct aead_instance *inst = aead_alg_instance(krb5enc);
@@ -238,11 +238,12 @@ static int krb5enc_verify_hash(struct aead_request *req, void *hash)
 	struct krb5enc_request_ctx *areq_ctx = aead_request_ctx(req);
 	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ictx->reqoff);
 	unsigned int authsize = crypto_aead_authsize(krb5enc);
-	u8 *ihash = ahreq->result + authsize;
+	u8 *calc_hash = areq_ctx->tail;
+	u8 *msg_hash  = areq_ctx->tail + authsize;
 
-	scatterwalk_map_and_copy(ihash, req->src, ahreq->nbytes, authsize, 0);
+	scatterwalk_map_and_copy(msg_hash, req->src, ahreq->nbytes, authsize, 0);
 
-	if (crypto_memneq(ihash, ahreq->result, authsize))
+	if (crypto_memneq(msg_hash, calc_hash, authsize))
 		return -EBADMSG;
 	return 0;
 }
@@ -254,7 +255,7 @@ static void krb5enc_decrypt_hash_done(void *data, int err)
 	if (err)
 		return krb5enc_request_complete(req, err);
 
-	err = krb5enc_verify_hash(req, 0);
+	err = krb5enc_verify_hash(req);
 	krb5enc_request_complete(req, err);
 }
 
@@ -284,7 +285,7 @@ static int krb5enc_dispatch_decrypt_hash(struct aead_request *req)
 	if (err < 0)
 		return err;
 
-	return krb5enc_verify_hash(req, hash);
+	return krb5enc_verify_hash(req);
 }
 
 /*
@@ -352,7 +353,7 @@ static int krb5enc_init_tfm(struct crypto_aead *tfm)
 	crypto_aead_set_reqsize(
 		tfm,
 		sizeof(struct krb5enc_request_ctx) +
-		ictx->reqoff +
+		ictx->reqoff + /* Space for two checksums */
 		umax(sizeof(struct ahash_request) + crypto_ahash_reqsize(auth),
 		     sizeof(struct skcipher_request) + crypto_skcipher_reqsize(enc)));
 

[RFC PATCH 04/24] crypto/krb5: Test manager data

[David Howells]

Add Kerberos crypto tests to the test manager database.  This covers:

	camellia128-cts-cmac		samples from RFC6803
	camellia256-cts-cmac		samples from RFC6803
	aes128-cts-hmac-sha256-128	samples from RFC8009
	aes256-cts-hmac-sha384-192	samples from RFC8009

but not:

	aes128-cts-hmac-sha1-96
	aes256-cts-hmac-sha1-96

as the test samples in RFC3962 don't seem to be suitable.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/testmgr.c |  16 ++
 crypto/testmgr.h | 401 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 417 insertions(+)

diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index 1f5f48ab18c7..94d70bf39de9 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -4515,6 +4515,12 @@ static const struct alg_test_desc alg_test_descs[] = {
 		.alg = "authenc(hmac(sha256),ctr(aes))",
 		.test = alg_test_null,
 		.fips_allowed = 1,
+	}, {
+		.alg = "authenc(hmac(sha256),cts(cbc(aes)))",
+		.test = alg_test_aead,
+		.suite = {
+			.aead = __VECS(krb5_test_aes128_cts_hmac_sha256_128)
+		}
 	}, {
 		.alg = "authenc(hmac(sha256),rfc3686(ctr(aes)))",
 		.test = alg_test_null,
@@ -4535,6 +4541,12 @@ static const struct alg_test_desc alg_test_descs[] = {
 		.alg = "authenc(hmac(sha384),ctr(aes))",
 		.test = alg_test_null,
 		.fips_allowed = 1,
+	}, {
+		.alg = "authenc(hmac(sha384),cts(cbc(aes)))",
+		.test = alg_test_aead,
+		.suite = {
+			.aead = __VECS(krb5_test_aes256_cts_hmac_sha384_192)
+		}
 	}, {
 		.alg = "authenc(hmac(sha384),rfc3686(ctr(aes)))",
 		.test = alg_test_null,
@@ -5408,6 +5420,10 @@ static const struct alg_test_desc alg_test_descs[] = {
 		.alg = "jitterentropy_rng",
 		.fips_allowed = 1,
 		.test = alg_test_null,
+	}, {
+		.alg = "krb5enc(cmac(camellia),cts(cbc(camellia)))",
+		.test = alg_test_aead,
+		.suite.aead = __VECS(krb5_test_camellia_cts_cmac)
 	}, {
 		.alg = "kw(aes)",
 		.test = alg_test_skcipher,
diff --git a/crypto/testmgr.h b/crypto/testmgr.h
index 430d33d9ac13..c1fa0e6e8108 100644
--- a/crypto/testmgr.h
+++ b/crypto/testmgr.h
@@ -39086,4 +39086,405 @@ static const struct cipher_testvec aes_hctr2_tv_template[] = {
 
 };
 
+static const struct aead_testvec krb5_test_aes128_cts_hmac_sha256_128[] = {
+	/* rfc8009 Appendix A */
+	{
+		/* "enc no plain" */
+		.key	=
+#ifdef CONFIG_CPU_BIG_ENDIAN
+		"\x00\x08\x00\x01" // BE rtattr
+#else
+		"\x08\x00\x01\x00" // LE rtattr
+#endif
+		"\x00\x00\x00\x10" // crypto_authenc_key_param
+		"\x9F\xDA\x0E\x56\xAB\x2D\x85\xE1\x56\x9A\x68\x86\x96\xC2\x6A\x6C" // Ki
+		"\x9B\x19\x7D\xD1\xE8\xC5\x60\x9D\x6E\x67\xC3\xE3\x7C\x62\xC7\x2E", // Ke
+		.klen	= 4 + 4 + 16 + 16,
+		.ptext	=
+		"\x7E\x58\x95\xEA\xF2\x67\x24\x35\xBA\xD8\x17\xF5\x45\xA3\x71\x48" // Confounder
+		"", // Plain
+		.plen	= 16 + 0,
+		.ctext	=
+		"\xEF\x85\xFB\x89\x0B\xB8\x47\x2F\x4D\xAB\x20\x39\x4D\xCA\x78\x1D"
+		"\xAD\x87\x7E\xDA\x39\xD5\x0C\x87\x0C\x0D\x5A\x0A\x8E\x48\xC7\x18",
+		.clen	= 16 + 0 + 16,
+		.assoc	= "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", // IV
+		.alen	= 16,
+	}, {
+		/* "enc plain<block" */
+		.key	=
+#ifdef CONFIG_CPU_BIG_ENDIAN
+		"\x00\x08\x00\x01" // BE rtattr
+#else
+		"\x08\x00\x01\x00" // LE rtattr
+#endif
+		"\x00\x00\x00\x10" // crypto_authenc_key_param
+		"\x9F\xDA\x0E\x56\xAB\x2D\x85\xE1\x56\x9A\x68\x86\x96\xC2\x6A\x6C" // Ki
+		"\x9B\x19\x7D\xD1\xE8\xC5\x60\x9D\x6E\x67\xC3\xE3\x7C\x62\xC7\x2E", // Ke
+		.klen	= 4 + 4 + 16 + 16,
+		.ptext	=
+		"\x7B\xCA\x28\x5E\x2F\xD4\x13\x0F\xB5\x5B\x1A\x5C\x83\xBC\x5B\x24" // Confounder
+		"\x00\x01\x02\x03\x04\x05", // Plain
+		.plen	= 16 + 6,
+		.ctext	=
+		"\x84\xD7\xF3\x07\x54\xED\x98\x7B\xAB\x0B\xF3\x50\x6B\xEB\x09\xCF"
+		"\xB5\x54\x02\xCE\xF7\xE6\x87\x7C\xE9\x9E\x24\x7E\x52\xD1\x6E\xD4"
+		"\x42\x1D\xFD\xF8\x97\x6C",
+		.clen	= 16 + 6 + 16,
+		.assoc	= "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", // IV
+		.alen	= 16,
+	}, {
+		/* "enc plain==block" */
+		.key	=
+#ifdef CONFIG_CPU_BIG_ENDIAN
+		"\x00\x08\x00\x01" // BE rtattr
+#else
+		"\x08\x00\x01\x00" // LE rtattr
+#endif
+		"\x00\x00\x00\x10" // crypto_authenc_key_param
+		"\x9F\xDA\x0E\x56\xAB\x2D\x85\xE1\x56\x9A\x68\x86\x96\xC2\x6A\x6C" // Ki
+		"\x9B\x19\x7D\xD1\xE8\xC5\x60\x9D\x6E\x67\xC3\xE3\x7C\x62\xC7\x2E", // Ke
+		.klen	= 4 + 4 + 16 + 16,
+		.ptext	=
+		"\x56\xAB\x21\x71\x3F\xF6\x2C\x0A\x14\x57\x20\x0F\x6F\xA9\x94\x8F" // Confounder
+		"\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0A\x0B\x0C\x0D\x0E\x0F", // Plain
+		.plen	= 16 + 16,
+		.ctext	=
+		"\x35\x17\xD6\x40\xF5\x0D\xDC\x8A\xD3\x62\x87\x22\xB3\x56\x9D\x2A"
+		"\xE0\x74\x93\xFA\x82\x63\x25\x40\x80\xEA\x65\xC1\x00\x8E\x8F\xC2"
+		"\x95\xFB\x48\x52\xE7\xD8\x3E\x1E\x7C\x48\xC3\x7E\xEB\xE6\xB0\xD3",
+		.clen	= 16 + 16 + 16,
+		.assoc	= "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", // IV
+		.alen	= 16,
+	}, {
+		/* "enc plain>block" */
+		.key	=
+#ifdef CONFIG_CPU_BIG_ENDIAN
+		"\x00\x08\x00\x01" // BE rtattr
+#else
+		"\x08\x00\x01\x00" // LE rtattr
+#endif
+		"\x00\x00\x00\x10" // crypto_authenc_key_param
+		"\x9F\xDA\x0E\x56\xAB\x2D\x85\xE1\x56\x9A\x68\x86\x96\xC2\x6A\x6C" // Ki
+		"\x9B\x19\x7D\xD1\xE8\xC5\x60\x9D\x6E\x67\xC3\xE3\x7C\x62\xC7\x2E", // Ke
+		.klen	= 4 + 4 + 16 + 16,
+		.ptext	=
+		"\xA7\xA4\xE2\x9A\x47\x28\xCE\x10\x66\x4F\xB6\x4E\x49\xAD\x3F\xAC" // Confounder
+		"\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0A\x0B\x0C\x0D\x0E\x0F"
+		"\x10\x11\x12\x13\x14", // Plain
+		.plen	= 16 + 21,
+		.ctext	=
+		"\x72\x0F\x73\xB1\x8D\x98\x59\xCD\x6C\xCB\x43\x46\x11\x5C\xD3\x36"
+		"\xC7\x0F\x58\xED\xC0\xC4\x43\x7C\x55\x73\x54\x4C\x31\xC8\x13\xBC"
+		"\xE1\xE6\xD0\x72\xC1\x86\xB3\x9A\x41\x3C\x2F\x92\xCA\x9B\x83\x34"
+		"\xA2\x87\xFF\xCB\xFC",
+		.clen	= 16 + 21 + 16,
+		.assoc	= "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", // IV
+		.alen	= 16,
+	},
+};
+
+static const struct aead_testvec krb5_test_aes256_cts_hmac_sha384_192[] = {
+	/* rfc8009 Appendix A */
+	{
+		/* "enc no plain" */
+		.key	=
+#ifdef CONFIG_CPU_BIG_ENDIAN
+		"\x00\x08\x00\x01" // BE rtattr
+#else
+		"\x08\x00\x01\x00" // LE rtattr
+#endif
+		"\x00\x00\x00\x20" // crypto_authenc_key_param
+		"\x69\xB1\x65\x14\xE3\xCD\x8E\x56\xB8\x20\x10\xD5\xC7\x30\x12\xB6"
+		"\x22\xC4\xD0\x0F\xFC\x23\xED\x1F" // Ki
+		"\x56\xAB\x22\xBE\xE6\x3D\x82\xD7\xBC\x52\x27\xF6\x77\x3F\x8E\xA7"
+		"\xA5\xEB\x1C\x82\x51\x60\xC3\x83\x12\x98\x0C\x44\x2E\x5C\x7E\x49", // Ke
+		.klen	= 4 + 4 + 32 + 24,
+		.ptext	=
+		"\xF7\x64\xE9\xFA\x15\xC2\x76\x47\x8B\x2C\x7D\x0C\x4E\x5F\x58\xE4" // Confounder
+		"", // Plain
+		.plen	= 16 + 0,
+		.ctext	=
+		"\x41\xF5\x3F\xA5\xBF\xE7\x02\x6D\x91\xFA\xF9\xBE\x95\x91\x95\xA0"
+		"\x58\x70\x72\x73\xA9\x6A\x40\xF0\xA0\x19\x60\x62\x1A\xC6\x12\x74"
+		"\x8B\x9B\xBF\xBE\x7E\xB4\xCE\x3C",
+		.clen	= 16 + 0 + 24,
+		.assoc	= "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", // IV
+		.alen	= 16,
+	}, {
+		/* "enc plain<block" */
+		.key	=
+#ifdef CONFIG_CPU_BIG_ENDIAN
+		"\x00\x08\x00\x01" // BE rtattr
+#else
+		"\x08\x00\x01\x00" // LE rtattr
+#endif
+		"\x00\x00\x00\x20" // crypto_authenc_key_param
+		"\x69\xB1\x65\x14\xE3\xCD\x8E\x56\xB8\x20\x10\xD5\xC7\x30\x12\xB6"
+		"\x22\xC4\xD0\x0F\xFC\x23\xED\x1F" // Ki
+		"\x56\xAB\x22\xBE\xE6\x3D\x82\xD7\xBC\x52\x27\xF6\x77\x3F\x8E\xA7"
+		"\xA5\xEB\x1C\x82\x51\x60\xC3\x83\x12\x98\x0C\x44\x2E\x5C\x7E\x49", // Ke
+		.klen	= 4 + 4 + 32 + 24,
+		.ptext	=
+		"\xB8\x0D\x32\x51\xC1\xF6\x47\x14\x94\x25\x6F\xFE\x71\x2D\x0B\x9A" // Confounder
+		"\x00\x01\x02\x03\x04\x05", // Plain
+		.plen	= 16 + 6,
+		.ctext	=
+		"\x4E\xD7\xB3\x7C\x2B\xCA\xC8\xF7\x4F\x23\xC1\xCF\x07\xE6\x2B\xC7"
+		"\xB7\x5F\xB3\xF6\x37\xB9\xF5\x59\xC7\xF6\x64\xF6\x9E\xAB\x7B\x60"
+		"\x92\x23\x75\x26\xEA\x0D\x1F\x61\xCB\x20\xD6\x9D\x10\xF2",
+		.clen	= 16 + 6 + 24,
+		.assoc	= "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", // IV
+		.alen	= 16,
+	}, {
+		/* "enc plain==block" */
+		.key	=
+#ifdef CONFIG_CPU_BIG_ENDIAN
+		"\x00\x08\x00\x01" // BE rtattr
+#else
+		"\x08\x00\x01\x00" // LE rtattr
+#endif
+		"\x00\x00\x00\x20" // crypto_authenc_key_param
+		"\x69\xB1\x65\x14\xE3\xCD\x8E\x56\xB8\x20\x10\xD5\xC7\x30\x12\xB6"
+		"\x22\xC4\xD0\x0F\xFC\x23\xED\x1F" // Ki
+		"\x56\xAB\x22\xBE\xE6\x3D\x82\xD7\xBC\x52\x27\xF6\x77\x3F\x8E\xA7"
+		"\xA5\xEB\x1C\x82\x51\x60\xC3\x83\x12\x98\x0C\x44\x2E\x5C\x7E\x49", // Ke
+		.klen	= 4 + 4 + 32 + 24,
+		.ptext	=
+		"\x53\xBF\x8A\x0D\x10\x52\x65\xD4\xE2\x76\x42\x86\x24\xCE\x5E\x63" // Confounder
+		"\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0A\x0B\x0C\x0D\x0E\x0F", // Plain
+		.plen	= 16 + 16,
+		.ctext	=
+		"\xBC\x47\xFF\xEC\x79\x98\xEB\x91\xE8\x11\x5C\xF8\xD1\x9D\xAC\x4B"
+		"\xBB\xE2\xE1\x63\xE8\x7D\xD3\x7F\x49\xBE\xCA\x92\x02\x77\x64\xF6"
+		"\x8C\xF5\x1F\x14\xD7\x98\xC2\x27\x3F\x35\xDF\x57\x4D\x1F\x93\x2E"
+		"\x40\xC4\xFF\x25\x5B\x36\xA2\x66",
+		.clen	= 16 + 16 + 24,
+		.assoc	= "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", // IV
+		.alen	= 16,
+	}, {
+		/* "enc plain>block" */
+		.key	=
+#ifdef CONFIG_CPU_BIG_ENDIAN
+		"\x00\x08\x00\x01" // BE rtattr
+#else
+		"\x08\x00\x01\x00" // LE rtattr
+#endif
+		"\x00\x00\x00\x20" // crypto_authenc_key_param
+		"\x69\xB1\x65\x14\xE3\xCD\x8E\x56\xB8\x20\x10\xD5\xC7\x30\x12\xB6"
+		"\x22\xC4\xD0\x0F\xFC\x23\xED\x1F" // Ki
+		"\x56\xAB\x22\xBE\xE6\x3D\x82\xD7\xBC\x52\x27\xF6\x77\x3F\x8E\xA7"
+		"\xA5\xEB\x1C\x82\x51\x60\xC3\x83\x12\x98\x0C\x44\x2E\x5C\x7E\x49", // Ke
+		.klen	= 4 + 4 + 32 + 24,
+		.ptext	=
+		"\x76\x3E\x65\x36\x7E\x86\x4F\x02\xF5\x51\x53\xC7\xE3\xB5\x8A\xF1" // Confounder
+		"\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0A\x0B\x0C\x0D\x0E\x0F"
+		"\x10\x11\x12\x13\x14", // Plain
+		.plen	= 16 + 21,
+		.ctext	=
+		"\x40\x01\x3E\x2D\xF5\x8E\x87\x51\x95\x7D\x28\x78\xBC\xD2\xD6\xFE"
+		"\x10\x1C\xCF\xD5\x56\xCB\x1E\xAE\x79\xDB\x3C\x3E\xE8\x64\x29\xF2"
+		"\xB2\xA6\x02\xAC\x86\xFE\xF6\xEC\xB6\x47\xD6\x29\x5F\xAE\x07\x7A"
+		"\x1F\xEB\x51\x75\x08\xD2\xC1\x6B\x41\x92\xE0\x1F\x62",
+		.clen	= 16 + 21 + 24,
+		.assoc	= "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", // IV
+		.alen	= 16,
+	},
+};
+
+static const struct aead_testvec krb5_test_camellia_cts_cmac[] = {
+	/* rfc6803 sec 10 */
+	{
+		// "enc no plain"
+		.key	=
+		"\x00\x00\x00\x01" // Format
+		"\x00\x00\x00\x10" // Ke len
+		"\x00\x00\x00\x10" // Ki len
+		"\xe9\x9b\x82\xb3\x6c\x4a\xe8\xea\x19\xe9\x5d\xfa\x9e\xde\x88\x2c" // Ke
+		"\x45\xeb\x66\xe2\xef\xa8\x77\x8f\x7d\xf1\x46\x54\x53\x05\x98\x06", // Ki
+		.klen	= 3 * 4 + 16 * 2,
+		.ptext	=
+		"\xB6\x98\x22\xA1\x9A\x6B\x09\xC0\xEB\xC8\x55\x7D\x1F\x1B\x6C\x0A" // Confounder
+		"", // Plain
+		.plen	= 16 + 0,
+		.ctext	=
+		"\xC4\x66\xF1\x87\x10\x69\x92\x1E\xDB\x7C\x6F\xDE\x24\x4A\x52\xDB"
+		"\x0B\xA1\x0E\xDC\x19\x7B\xDB\x80\x06\x65\x8C\xA3\xCC\xCE\x6E\xB8",
+		.clen	= 16 + 0 + 16,
+	}, {
+		// "enc 1 plain",
+		.key	=
+		"\x00\x00\x00\x01" // Format
+		"\x00\x00\x00\x10" // Ke len
+		"\x00\x00\x00\x10" // Ki len
+		"\xa7\xed\xcd\x53\x97\xea\x6d\x12\xb0\xaf\xf4\xcb\x8d\xaa\x57\xad" // Ke
+		"\x13\x5f\xe7\x11\x6f\x53\xc2\xaa\x36\x12\xb7\xea\xe0\xf2\x84\xaa", // Ki
+		.klen	= 4 * 3 + 16 * 2,
+		.ptext	=
+		"\x6F\x2F\xC3\xC2\xA1\x66\xFD\x88\x98\x96\x7A\x83\xDE\x95\x96\xD9" // Confounder
+		"1", // Plain
+		.plen	= 16 + 1,
+		.ctext	=
+		"\x84\x2D\x21\xFD\x95\x03\x11\xC0\xDD\x46\x4A\x3F\x4B\xE8\xD6\xDA"
+		"\x88\xA5\x6D\x55\x9C\x9B\x47\xD3\xF9\xA8\x50\x67\xAF\x66\x15\x59"
+		"\xB8",
+		.clen	= 16 + 1 + 16,
+	}, {
+		// "enc 9 plain",
+		.key	=
+		"\x00\x00\x00\x01" // Format
+		"\x00\x00\x00\x10" // Ke len
+		"\x00\x00\x00\x10" // Ki len
+		"\xdd\xe4\x2e\xca\x7c\xd9\x86\x3f\xc3\xce\x89\xcb\xc9\x43\x62\xd7" // Ke
+		"\x10\x2c\x34\xd0\x75\x74\x9f\x77\x8a\x15\xca\xd1\xe9\x7d\xa9\x86", // Ki
+		.klen	= 4 * 3 + 16 * 2,
+		.ptext	=
+		"\xA5\xB4\xA7\x1E\x07\x7A\xEE\xF9\x3C\x87\x63\xC1\x8F\xDB\x1F\x10" // Confounder
+		"9 bytesss", // Plain
+		.plen	= 16 + 9,
+		.ctext	=
+		"\x61\x9F\xF0\x72\xE3\x62\x86\xFF\x0A\x28\xDE\xB3\xA3\x52\xEC\x0D"
+		"\x0E\xDF\x5C\x51\x60\xD6\x63\xC9\x01\x75\x8C\xCF\x9D\x1E\xD3\x3D"
+		"\x71\xDB\x8F\x23\xAA\xBF\x83\x48\xA0",
+		.clen	= 16 + 9 + 16,
+	}, {
+		// "enc 13 plain",
+		.key	=
+		"\x00\x00\x00\x01" // Format
+		"\x00\x00\x00\x10" // Ke len
+		"\x00\x00\x00\x10" // Ki len
+		"\xc3\x11\x3a\x25\x85\x90\xb9\xae\xbf\x72\x1b\x1a\xf6\xb0\xcb\xf8" // Ke
+		"\xb8\xc4\x38\xcc\x1a\x00\x60\xfc\x91\x3a\x8e\x07\x16\x96\xbd\x08", // Ki
+		.klen	= 4 * 3 + 16 * 2,
+		.ptext	=
+		"\x19\xFE\xE4\x0D\x81\x0C\x52\x4B\x5B\x22\xF0\x18\x74\xC6\x93\xDA" // Confounder
+		"13 bytes byte", // Plain
+		.plen	= 16 + 13,
+		.ctext	=
+		"\xB8\xEC\xA3\x16\x7A\xE6\x31\x55\x12\xE5\x9F\x98\xA7\xC5\x00\x20"
+		"\x5E\x5F\x63\xFF\x3B\xB3\x89\xAF\x1C\x41\xA2\x1D\x64\x0D\x86\x15"
+		"\xC9\xED\x3F\xBE\xB0\x5A\xB6\xAC\xB6\x76\x89\xB5\xEA",
+		.clen	= 16 + 13 + 16,
+	}, {
+		// "enc 30 plain",
+		.key	=
+		"\x00\x00\x00\x01" // Format
+		"\x00\x00\x00\x10" // Ke len
+		"\x00\x00\x00\x10" // Ki len
+		"\x8b\x07\xee\xd3\x01\x49\x91\x6a\xa2\x0d\xb3\xf5\xce\xd8\xaf\xad" // Ke
+		"\x18\xaf\x19\xb0\x23\x74\x44\xfd\x75\x04\xad\x7d\xbd\x48\xad\xd3", // Ki
+		.klen	= 4 * 3 + 16 * 2,
+		.ptext	=
+		"\xCA\x7A\x7A\xB4\xBE\x19\x2D\xAB\xD6\x03\x50\x6D\xB1\x9C\x39\xE2" // Confounder
+		"30 bytes bytes bytes bytes byt", // Plain
+		.plen	= 16 + 30,
+		.ctext	=
+		"\xA2\x6A\x39\x05\xA4\xFF\xD5\x81\x6B\x7B\x1E\x27\x38\x0D\x08\x09"
+		"\x0C\x8E\xC1\xF3\x04\x49\x6E\x1A\xBD\xCD\x2B\xDC\xD1\xDF\xFC\x66"
+		"\x09\x89\xE1\x17\xA7\x13\xDD\xBB\x57\xA4\x14\x6C\x15\x87\xCB\xA4"
+		"\x35\x66\x65\x59\x1D\x22\x40\x28\x2F\x58\x42\xB1\x05\xA5",
+		.clen	= 16 + 30 + 16,
+	}, {
+		// "enc no plain",
+		.key	=
+		"\x00\x00\x00\x01" // Format
+		"\x00\x00\x00\x20" // Ke len
+		"\x00\x00\x00\x20" // Ki len
+		"\x6c\xcb\x3f\x25\xd8\xae\x57\xf4\xe8\xf6\xca\x47\x4b\xdd\xef\xf1"
+		"\x16\xce\x13\x1b\x3f\x71\x01\x2e\x75\x6d\x6b\x1e\x3f\x70\xa7\xf1" // Ke
+		"\xa2\xb8\x33\xe9\x43\xbb\x10\xee\x53\xb4\xa1\x9b\xc2\xbb\xc7\xe1"
+		"\x9b\x87\xad\x5d\xe9\x21\x22\xa4\x33\x8b\xe6\xf7\x32\xfd\x8a\x0e", // Ki
+		.klen	= 4 * 3 + 32 * 2,
+		.ptext	=
+		"\x3C\xBB\xD2\xB4\x59\x17\x94\x10\x67\xF9\x65\x99\xBB\x98\x92\x6C" // Confounder
+		"", // Plain
+		.plen	= 16 + 0,
+		.ctext	=
+		"\x03\x88\x6D\x03\x31\x0B\x47\xA6\xD8\xF0\x6D\x7B\x94\xD1\xDD\x83"
+		"\x7E\xCC\xE3\x15\xEF\x65\x2A\xFF\x62\x08\x59\xD9\x4A\x25\x92\x66",
+		.clen	= 16 + 0 + 16,
+	}, {
+		// "enc 1 plain",
+		.key	=
+		"\x00\x00\x00\x01" // Format
+		"\x00\x00\x00\x20" // Ke len
+		"\x00\x00\x00\x20" // Ki len
+		"\xe9\x31\x73\xaa\x01\xeb\x3c\x24\x62\x31\xda\xfc\x78\x02\xee\x32"
+		"\xaf\x24\x85\x1d\x8c\x73\x87\xd1\x8c\xb9\xb2\xc5\xb7\xf5\x70\xb8" // Ke
+		"\x84\x61\x4b\xfa\x98\xf1\x74\x8a\xa4\xaf\x99\x2b\x8c\x26\x28\x0d"
+		"\xc8\x98\x73\x29\xdf\x77\x5c\x1d\xb0\x4a\x43\xf1\x21\xaa\x86\x65", // Ki
+		.klen	= 4 * 3 + 32 * 2,
+		.ptext	=
+		"\xDE\xF4\x87\xFC\xEB\xE6\xDE\x63\x46\xD4\xDA\x45\x21\xBB\xA2\xD2" // Confounder
+		"1", // Plain
+		.plen	= 16 + 1,
+		.ctext	=
+		"\x2C\x9C\x15\x70\x13\x3C\x99\xBF\x6A\x34\xBC\x1B\x02\x12\x00\x2F"
+		"\xD1\x94\x33\x87\x49\xDB\x41\x35\x49\x7A\x34\x7C\xFC\xD9\xD1\x8A"
+		"\x12",
+		.clen	= 16 + 1 + 16,
+	}, {
+		// "enc 9 plain",
+		.key	=
+		"\x00\x00\x00\x01" // Format
+		"\x00\x00\x00\x20" // Ke len
+		"\x00\x00\x00\x20" // Ki len
+		"\xcd\xa2\xd3\x9a\x9b\x24\x3f\xfe\xb5\x6e\x8d\x5f\x4b\xd5\x28\x74"
+		"\x1e\xcb\x52\x0c\x62\x12\x3f\xb0\x40\xb8\x41\x8b\x15\xc7\xd7\x0c" // Ke
+		"\x47\xb9\xf5\xba\xd7\x63\x00\x58\x2a\x54\x45\xfa\x0c\x1b\x29\xc3"
+		"\xaa\x83\xec\x63\xb9\x0b\x4a\xb0\x08\x48\xc1\x85\x67\x4f\x44\xa7", // Ki
+		.klen	= 4 * 3 + 32 * 2,
+		.ptext	=
+		"\xAD\x4F\xF9\x04\xD3\x4E\x55\x53\x84\xB1\x41\x00\xFC\x46\x5F\x88" // Confounder
+		"9 bytesss", // Plain
+		.plen	= 16 + 9,
+		.ctext	=
+		"\x9C\x6D\xE7\x5F\x81\x2D\xE7\xED\x0D\x28\xB2\x96\x35\x57\xA1\x15"
+		"\x64\x09\x98\x27\x5B\x0A\xF5\x15\x27\x09\x91\x3F\xF5\x2A\x2A\x9C"
+		"\x8E\x63\xB8\x72\xF9\x2E\x64\xC8\x39",
+		.clen	= 16 + 9 + 16,
+	}, {
+		// "enc 13 plain",
+		.key	=
+		"\x00\x00\x00\x01" // Format
+		"\x00\x00\x00\x20" // Ke len
+		"\x00\x00\x00\x20" // Ki len
+		"\xcd\x8a\x10\xe2\x79\xda\xdd\xb6\x90\x1e\xc3\x0b\xdf\x98\x73\x25"
+		"\x0f\x6e\xfc\x6a\x77\x36\x7d\x74\xdc\x3e\xe7\xf7\x4b\xc7\x77\x4e" // Ke
+		"\x15\x2f\x8c\x9d\xc9\x85\x79\x6e\xb1\x94\xed\x14\xc5\x9e\xac\xdd"
+		"\x41\x8a\x33\x32\x36\xb7\x8f\xaf\xa7\xc7\x9b\x04\xe0\xac\xe7\xbf", // Ki
+		.klen	= 4 * 3 + 32 * 2,
+		.ptext	=
+		"\xCF\x9B\xCA\x6D\xF1\x14\x4E\x0C\x0A\xF9\xB8\xF3\x4C\x90\xD5\x14" // Confounder
+		"13 bytes byte",
+		.plen	= 16 + 13,
+		.ctext	=
+		"\xEE\xEC\x85\xA9\x81\x3C\xDC\x53\x67\x72\xAB\x9B\x42\xDE\xFC\x57"
+		"\x06\xF7\x26\xE9\x75\xDD\xE0\x5A\x87\xEB\x54\x06\xEA\x32\x4C\xA1"
+		"\x85\xC9\x98\x6B\x42\xAA\xBE\x79\x4B\x84\x82\x1B\xEE",
+		.clen	= 16 + 13 + 16,
+	}, {
+		// "enc 30 plain",
+		.key	=
+		"\x00\x00\x00\x01" // Format
+		"\x00\x00\x00\x20" // Ke len
+		"\x00\x00\x00\x20" // Ki len
+		"\x1d\x51\x47\xf3\x4b\xb0\x01\xa0\x4a\x68\xa7\x13\x46\xe7\x65\x4e"
+		"\x02\x23\xa6\x0d\x90\xbc\x2b\x79\xb4\xd8\x79\x56\xd4\x7c\xd4\x2a" // Ke
+		"\x04\x8d\xeb\xf7\xb1\x2c\x09\x32\xe8\xb2\x96\x99\x6c\x23\xf8\xb7"
+		"\x9d\x59\xb9\x7e\xa1\x19\xfc\x0c\x15\x6b\xf7\x88\xdc\x8c\x85\xe8", // Ki
+		.klen	= 4 * 3 + 32 * 2,
+		.ptext	=
+		"\x64\x4D\xEF\x38\xDA\x35\x00\x72\x75\x87\x8D\x21\x68\x55\xE2\x28" // Confounder
+		"30 bytes bytes bytes bytes byt", // Plain
+		.plen	= 16 + 30,
+		.ctext	=
+		"\x0E\x44\x68\x09\x85\x85\x5F\x2D\x1F\x18\x12\x52\x9C\xA8\x3B\xFD"
+		"\x8E\x34\x9D\xE6\xFD\x9A\xDA\x0B\xAA\xA0\x48\xD6\x8E\x26\x5F\xEB"
+		"\xF3\x4A\xD1\x25\x5A\x34\x49\x99\xAD\x37\x14\x68\x87\xA6\xC6\x84"
+		"\x57\x31\xAC\x7F\x46\x37\x6A\x05\x04\xCD\x06\x57\x14\x74",
+		.clen	= 16 + 30 + 16,
+	},
+};
+
 #endif	/* _CRYPTO_TESTMGR_H */

[RFC PATCH 05/24] crypto/krb5: Implement Kerberos crypto core

[David Howells]

Provide core structures, an encoding-type registry and basic module and
config bits for a generic Kerberos crypto library.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/Kconfig         |   1 +
 crypto/Makefile        |   2 +
 crypto/krb5/Kconfig    |  14 ++++++
 crypto/krb5/Makefile   |   9 ++++
 crypto/krb5/internal.h | 112 +++++++++++++++++++++++++++++++++++++++++
 crypto/krb5/krb5_api.c |  42 ++++++++++++++++
 include/crypto/krb5.h  |  54 ++++++++++++++++++++
 7 files changed, 234 insertions(+)
 create mode 100644 crypto/krb5/Kconfig
 create mode 100644 crypto/krb5/Makefile
 create mode 100644 crypto/krb5/internal.h
 create mode 100644 crypto/krb5/krb5_api.c

diff --git a/crypto/Kconfig b/crypto/Kconfig
index 18b1a3b3a258..d5d5d21c56ff 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -1489,5 +1489,6 @@ endif
 source "drivers/crypto/Kconfig"
 source "crypto/asymmetric_keys/Kconfig"
 source "certs/Kconfig"
+source "crypto/krb5/Kconfig"
 
 endif	# if CRYPTO
diff --git a/crypto/Makefile b/crypto/Makefile
index eb40638c6c04..eb5ef38d47e0 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -214,3 +214,5 @@ obj-$(CONFIG_CRYPTO_SIMD) += crypto_simd.o
 # Key derivation function
 #
 obj-$(CONFIG_CRYPTO_KDF800108_CTR) += kdf_sp800108.o
+
+obj-$(CONFIG_CRYPTO_KRB5) += krb5/
diff --git a/crypto/krb5/Kconfig b/crypto/krb5/Kconfig
new file mode 100644
index 000000000000..079873618abf
--- /dev/null
+++ b/crypto/krb5/Kconfig
@@ -0,0 +1,14 @@
+config CRYPTO_KRB5
+	tristate "Kerberos 5 crypto"
+	select CRYPTO_MANAGER
+	select CRYPTO_KRB5ENC
+	select CRYPTO_AUTHENC
+	select CRYPTO_SKCIPHER
+	select CRYPTO_HASH_INFO
+	select CRYPTO_SHA1
+	select CRYPTO_CBC
+	select CRYPTO_CTS
+	select CRYPTO_AES
+	help
+	  Provide a library for provision of Kerberos-5-based crypto.  This is
+	  intended for network filesystems to use.
diff --git a/crypto/krb5/Makefile b/crypto/krb5/Makefile
new file mode 100644
index 000000000000..c450d0754772
--- /dev/null
+++ b/crypto/krb5/Makefile
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for asymmetric cryptographic keys
+#
+
+krb5-y += \
+	krb5_api.o
+
+obj-$(CONFIG_CRYPTO_KRB5) += krb5.o
diff --git a/crypto/krb5/internal.h b/crypto/krb5/internal.h
new file mode 100644
index 000000000000..3ede858be4f7
--- /dev/null
+++ b/crypto/krb5/internal.h
@@ -0,0 +1,112 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* Kerberos5 crypto internals
+ *
+ * Copyright (C) 2025 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#include <crypto/krb5.h>
+
+/*
+ * Profile used for key derivation and encryption.
+ */
+struct krb5_crypto_profile {
+	 /* Pseudo-random function */
+	int (*calc_PRF)(const struct krb5_enctype *krb5,
+			const struct krb5_buffer *protocol_key,
+			const struct krb5_buffer *octet_string,
+			struct krb5_buffer *result,
+			gfp_t gfp);
+
+	/* Checksum key derivation */
+	int (*calc_Kc)(const struct krb5_enctype *krb5,
+		       const struct krb5_buffer *TK,
+		       const struct krb5_buffer *usage_constant,
+		       struct krb5_buffer *Kc,
+		       gfp_t gfp);
+
+	/* Encryption key derivation */
+	int (*calc_Ke)(const struct krb5_enctype *krb5,
+		       const struct krb5_buffer *TK,
+		       const struct krb5_buffer *usage_constant,
+		       struct krb5_buffer *Ke,
+		       gfp_t gfp);
+
+	 /* Integrity key derivation */
+	int (*calc_Ki)(const struct krb5_enctype *krb5,
+		       const struct krb5_buffer *TK,
+		       const struct krb5_buffer *usage_constant,
+		       struct krb5_buffer *Ki,
+		       gfp_t gfp);
+
+	/* Derive the keys needed for an encryption AEAD object. */
+	int (*derive_encrypt_keys)(const struct krb5_enctype *krb5,
+				   const struct krb5_buffer *TK,
+				   unsigned int usage,
+				   struct krb5_buffer *setkey,
+				   gfp_t gfp);
+
+	/* Directly load the keys needed for an encryption AEAD object. */
+	int (*load_encrypt_keys)(const struct krb5_enctype *krb5,
+				 const struct krb5_buffer *Ke,
+				 const struct krb5_buffer *Ki,
+				 struct krb5_buffer *setkey,
+				 gfp_t gfp);
+
+	/* Derive the key needed for a checksum hash object. */
+	int (*derive_checksum_key)(const struct krb5_enctype *krb5,
+				   const struct krb5_buffer *TK,
+				   unsigned int usage,
+				   struct krb5_buffer *setkey,
+				   gfp_t gfp);
+
+	/* Directly load the keys needed for a checksum hash object. */
+	int (*load_checksum_key)(const struct krb5_enctype *krb5,
+				 const struct krb5_buffer *Kc,
+				 struct krb5_buffer *setkey,
+				 gfp_t gfp);
+
+	/* Encrypt data in-place, inserting confounder and checksum. */
+	ssize_t (*encrypt)(const struct krb5_enctype *krb5,
+			   struct crypto_aead *aead,
+			   struct scatterlist *sg, unsigned int nr_sg,
+			   size_t sg_len,
+			   size_t data_offset, size_t data_len,
+			   bool preconfounded);
+
+	/* Decrypt data in-place, removing confounder and checksum */
+	int (*decrypt)(const struct krb5_enctype *krb5,
+		       struct crypto_aead *aead,
+		       struct scatterlist *sg, unsigned int nr_sg,
+		       size_t *_offset, size_t *_len);
+
+	/* Generate a MIC on part of a packet, inserting the checksum */
+	ssize_t (*get_mic)(const struct krb5_enctype *krb5,
+			   struct crypto_shash *shash,
+			   const struct krb5_buffer *metadata,
+			   struct scatterlist *sg, unsigned int nr_sg,
+			   size_t sg_len,
+			   size_t data_offset, size_t data_len);
+
+	/* Verify the MIC on a piece of data, removing the checksum */
+	int (*verify_mic)(const struct krb5_enctype *krb5,
+			  struct crypto_shash *shash,
+			  const struct krb5_buffer *metadata,
+			  struct scatterlist *sg, unsigned int nr_sg,
+			  size_t *_offset, size_t *_len);
+};
+
+/*
+ * Crypto size/alignment rounding convenience macros.
+ */
+#define crypto_roundup(X) ((unsigned int)round_up((X), CRYPTO_MINALIGN))
+
+#define krb5_aead_size(TFM) \
+	crypto_roundup(sizeof(struct aead_request) + crypto_aead_reqsize(TFM))
+#define krb5_aead_ivsize(TFM) \
+	crypto_roundup(crypto_aead_ivsize(TFM))
+#define krb5_shash_size(TFM) \
+	crypto_roundup(sizeof(struct shash_desc) + crypto_shash_descsize(TFM))
+#define krb5_digest_size(TFM) \
+	crypto_roundup(crypto_shash_digestsize(TFM))
+#define round16(x) (((x) + 15) & ~15)
diff --git a/crypto/krb5/krb5_api.c b/crypto/krb5/krb5_api.c
new file mode 100644
index 000000000000..5c1cd5d07fc3
--- /dev/null
+++ b/crypto/krb5/krb5_api.c
@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Kerberos 5 crypto library.
+ *
+ * Copyright (C) 2025 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include "internal.h"
+
+MODULE_DESCRIPTION("Kerberos 5 crypto");
+MODULE_AUTHOR("Red Hat, Inc.");
+MODULE_LICENSE("GPL");
+
+static const struct krb5_enctype *const krb5_supported_enctypes[] = {
+};
+
+/**
+ * crypto_krb5_find_enctype - Find the handler for a Kerberos5 encryption type
+ * @enctype: The standard Kerberos encryption type number
+ *
+ * Look up a Kerberos encryption type by number.  If successful, returns a
+ * pointer to the type tables; returns NULL otherwise.
+ */
+const struct krb5_enctype *crypto_krb5_find_enctype(u32 enctype)
+{
+	const struct krb5_enctype *krb5;
+	size_t i;
+
+	for (i = 0; i < ARRAY_SIZE(krb5_supported_enctypes); i++) {
+		krb5 = krb5_supported_enctypes[i];
+		if (krb5->etype == enctype)
+			return krb5;
+	}
+
+	return NULL;
+}
+EXPORT_SYMBOL(crypto_krb5_find_enctype);
diff --git a/include/crypto/krb5.h b/include/crypto/krb5.h
index 8949a9b71de3..a67a5e1a0a4f 100644
--- a/include/crypto/krb5.h
+++ b/include/crypto/krb5.h
@@ -8,6 +8,12 @@
 #ifndef _CRYPTO_KRB5_H
 #define _CRYPTO_KRB5_H
 
+#include <linux/crypto.h>
+#include <crypto/aead.h>
+
+struct crypto_shash;
+struct scatterlist;
+
 /*
  * Per Kerberos v5 protocol spec crypto types from the wire.  These get mapped
  * to linux kernel crypto routines.
@@ -48,6 +54,54 @@
 #define KEY_USAGE_SEED_ENCRYPTION       (0xAA)
 #define KEY_USAGE_SEED_INTEGRITY        (0x55)
 
+/*
+ * Mode of operation.
+ */
+enum krb5_crypto_mode {
+	KRB5_CHECKSUM_MODE,	/* Checksum only */
+	KRB5_ENCRYPT_MODE,	/* Fully encrypted, possibly with integrity checksum */
+};
+
+struct krb5_buffer {
+	unsigned int	len;
+	void		*data;
+};
+
+/*
+ * Kerberos encoding type definition.
+ */
+struct krb5_enctype {
+	int		etype;		/* Encryption (key) type */
+	int		ctype;		/* Checksum type */
+	const char	*name;		/* "Friendly" name */
+	const char	*encrypt_name;	/* Crypto encrypt+checksum name */
+	const char	*cksum_name;	/* Crypto checksum name */
+	const char	*hash_name;	/* Crypto hash name */
+	const char	*derivation_enc; /* Cipher used in key derivation */
+	u16		block_len;	/* Length of encryption block */
+	u16		conf_len;	/* Length of confounder (normally == block_len) */
+	u16		cksum_len;	/* Length of checksum */
+	u16		key_bytes;	/* Length of raw key, in bytes */
+	u16		key_len;	/* Length of final key, in bytes */
+	u16		hash_len;	/* Length of hash in bytes */
+	u16		prf_len;	/* Length of PRF() result in bytes */
+	u16		Kc_len;		/* Length of Kc in bytes */
+	u16		Ke_len;		/* Length of Ke in bytes */
+	u16		Ki_len;		/* Length of Ki in bytes */
+	bool		keyed_cksum;	/* T if a keyed cksum */
+
+	const struct krb5_crypto_profile *profile;
+
+	int (*random_to_key)(const struct krb5_enctype *krb5,
+			     const struct krb5_buffer *in,
+			     struct krb5_buffer *out);	/* complete key generation */
+};
+
+/*
+ * krb5_api.c
+ */
+const struct krb5_enctype *crypto_krb5_find_enctype(u32 enctype);
+
 /*
  * krb5enc.c
  */

[RFC PATCH 06/24] crypto/krb5: Add an API to query the layout of the crypto section

[David Howells]

Provide some functions to allow the called to find out about the layout of
the crypto section:

 (1) Calculate, for a given size of data, how big a buffer will be
     required to hold it and where the data will be within it.

 (2) Calculate, for an amount of buffer, what's the maximum size of data
     that will fit therein, and where it will start.

 (3) Determine where the data will be in a received message.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/krb5/krb5_api.c | 108 +++++++++++++++++++++++++++++++++++++++++
 include/crypto/krb5.h  |   9 ++++
 2 files changed, 117 insertions(+)

diff --git a/crypto/krb5/krb5_api.c b/crypto/krb5/krb5_api.c
index 5c1cd5d07fc3..f6d1bc813daa 100644
--- a/crypto/krb5/krb5_api.c
+++ b/crypto/krb5/krb5_api.c
@@ -40,3 +40,111 @@ const struct krb5_enctype *crypto_krb5_find_enctype(u32 enctype)
 	return NULL;
 }
 EXPORT_SYMBOL(crypto_krb5_find_enctype);
+
+/**
+ * crypto_krb5_how_much_buffer - Work out how much buffer is required for an amount of data
+ * @krb5: The encoding to use.
+ * @mode: The mode in which to operated (checksum/encrypt)
+ * @data_size: How much data we want to allow for
+ * @_offset: Where to place the offset into the buffer
+ *
+ * Calculate how much buffer space is required to wrap a given amount of data.
+ * This allows for a confounder, padding and checksum as appropriate.  The
+ * amount of buffer required is returned and the offset into the buffer at
+ * which the data will start is placed in *_offset.
+ */
+size_t crypto_krb5_how_much_buffer(const struct krb5_enctype *krb5,
+				   enum krb5_crypto_mode mode,
+				   size_t data_size, size_t *_offset)
+{
+	switch (mode) {
+	case KRB5_CHECKSUM_MODE:
+		*_offset = krb5->cksum_len;
+		return krb5->cksum_len + data_size;
+
+	case KRB5_ENCRYPT_MODE:
+		*_offset = krb5->conf_len;
+		return krb5->conf_len + data_size + krb5->cksum_len;
+
+	default:
+		WARN_ON(1);
+		*_offset = 0;
+		return 0;
+	}
+}
+EXPORT_SYMBOL(crypto_krb5_how_much_buffer);
+
+/**
+ * crypto_krb5_how_much_data - Work out how much data can fit in an amount of buffer
+ * @krb5: The encoding to use.
+ * @mode: The mode in which to operated (checksum/encrypt)
+ * @_buffer_size: How much buffer we want to allow for (may be reduced)
+ * @_offset: Where to place the offset into the buffer
+ *
+ * Calculate how much data can be fitted into given amount of buffer.  This
+ * allows for a confounder, padding and checksum as appropriate.  The amount of
+ * data that will fit is returned, the amount of buffer required is shrunk to
+ * allow for alignment and the offset into the buffer at which the data will
+ * start is placed in *_offset.
+ */
+size_t crypto_krb5_how_much_data(const struct krb5_enctype *krb5,
+				 enum krb5_crypto_mode mode,
+				 size_t *_buffer_size, size_t *_offset)
+{
+	size_t buffer_size = *_buffer_size, data_size;
+
+	switch (mode) {
+	case KRB5_CHECKSUM_MODE:
+		if (WARN_ON(buffer_size < krb5->cksum_len + 1))
+			goto bad;
+		*_offset = krb5->cksum_len;
+		return buffer_size - krb5->cksum_len;
+
+	case KRB5_ENCRYPT_MODE:
+		if (WARN_ON(buffer_size < krb5->conf_len + 1 + krb5->cksum_len))
+			goto bad;
+		data_size = buffer_size - krb5->cksum_len;
+		*_offset = krb5->conf_len;
+		return data_size - krb5->conf_len;
+
+	default:
+		WARN_ON(1);
+		goto bad;
+	}
+
+bad:
+	*_offset = 0;
+	return 0;
+}
+EXPORT_SYMBOL(crypto_krb5_how_much_data);
+
+/**
+ * crypto_krb5_where_is_the_data - Find the data in a decrypted message
+ * @krb5: The encoding to use.
+ * @mode: Mode of operation
+ * @_offset: Offset of the secure blob in the buffer; updated to data offset.
+ * @_len: The length of the secure blob; updated to data length.
+ *
+ * Find the offset and size of the data in a secure message so that this
+ * information can be used in the metadata buffer which will get added to the
+ * digest by crypto_krb5_verify_mic().
+ */
+void crypto_krb5_where_is_the_data(const struct krb5_enctype *krb5,
+				   enum krb5_crypto_mode mode,
+				   size_t *_offset, size_t *_len)
+{
+	switch (mode) {
+	case KRB5_CHECKSUM_MODE:
+		*_offset += krb5->cksum_len;
+		*_len -= krb5->cksum_len;
+		return;
+	case KRB5_ENCRYPT_MODE:
+		*_offset += krb5->conf_len;
+		*_len -= krb5->conf_len + krb5->cksum_len;
+		return;
+	default:
+		WARN_ON_ONCE(1);
+		return;
+	}
+}
+EXPORT_SYMBOL(crypto_krb5_where_is_the_data);
diff --git a/include/crypto/krb5.h b/include/crypto/krb5.h
index a67a5e1a0a4f..e7dfe0b7c60d 100644
--- a/include/crypto/krb5.h
+++ b/include/crypto/krb5.h
@@ -101,6 +101,15 @@ struct krb5_enctype {
  * krb5_api.c
  */
 const struct krb5_enctype *crypto_krb5_find_enctype(u32 enctype);
+size_t crypto_krb5_how_much_buffer(const struct krb5_enctype *krb5,
+				   enum krb5_crypto_mode mode,
+				   size_t data_size, size_t *_offset);
+size_t crypto_krb5_how_much_data(const struct krb5_enctype *krb5,
+				 enum krb5_crypto_mode mode,
+				 size_t *_buffer_size, size_t *_offset);
+void crypto_krb5_where_is_the_data(const struct krb5_enctype *krb5,
+				   enum krb5_crypto_mode mode,
+				   size_t *_offset, size_t *_len);
 
 /*
  * krb5enc.c

[RFC PATCH 07/24] crypto/krb5: Add an API to alloc and prepare a crypto object

[David Howells]

Add an API by which users of the krb5 crypto library can get an allocated
and keyed crypto object.

For encryption-mode operation, an AEAD object is returned; for
checksum-mode operation, a synchronous hash object is returned.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/krb5/internal.h |  10 +++
 crypto/krb5/krb5_api.c | 144 +++++++++++++++++++++++++++++++++++++++++
 include/crypto/krb5.h  |   7 ++
 3 files changed, 161 insertions(+)

diff --git a/crypto/krb5/internal.h b/crypto/krb5/internal.h
index 3ede858be4f7..b542d24e5fa5 100644
--- a/crypto/krb5/internal.h
+++ b/crypto/krb5/internal.h
@@ -110,3 +110,13 @@ struct krb5_crypto_profile {
 #define krb5_digest_size(TFM) \
 	crypto_roundup(crypto_shash_digestsize(TFM))
 #define round16(x) (((x) + 15) & ~15)
+
+/*
+ * krb5_api.c
+ */
+struct crypto_aead *krb5_prepare_encryption(const struct krb5_enctype *krb5,
+					    const struct krb5_buffer *keys,
+					    gfp_t gfp);
+struct crypto_shash *krb5_prepare_checksum(const struct krb5_enctype *krb5,
+					   const struct krb5_buffer *Kc,
+					   gfp_t gfp);
diff --git a/crypto/krb5/krb5_api.c b/crypto/krb5/krb5_api.c
index f6d1bc813daa..f7f2528b3895 100644
--- a/crypto/krb5/krb5_api.c
+++ b/crypto/krb5/krb5_api.c
@@ -148,3 +148,147 @@ void crypto_krb5_where_is_the_data(const struct krb5_enctype *krb5,
 	}
 }
 EXPORT_SYMBOL(crypto_krb5_where_is_the_data);
+
+/*
+ * Prepare the encryption with derived key data.
+ */
+struct crypto_aead *krb5_prepare_encryption(const struct krb5_enctype *krb5,
+					    const struct krb5_buffer *keys,
+					    gfp_t gfp)
+{
+	struct crypto_aead *ci = NULL;
+	int ret = -ENOMEM;
+
+	ci = crypto_alloc_aead(krb5->encrypt_name, 0, 0);
+	if (IS_ERR(ci)) {
+		ret = PTR_ERR(ci);
+		if (ret == -ENOENT)
+			ret = -ENOPKG;
+		goto err;
+	}
+
+	ret = crypto_aead_setkey(ci, keys->data, keys->len);
+	if (ret < 0) {
+		pr_err("Couldn't set AEAD key %s: %d\n", krb5->encrypt_name, ret);
+		goto err_ci;
+	}
+
+	ret = crypto_aead_setauthsize(ci, krb5->cksum_len);
+	if (ret < 0) {
+		pr_err("Couldn't set AEAD authsize %s: %d\n", krb5->encrypt_name, ret);
+		goto err_ci;
+	}
+
+	return ci;
+err_ci:
+	crypto_free_aead(ci);
+err:
+	return ERR_PTR(ret);
+}
+
+/**
+ * crypto_krb5_prepare_encryption - Prepare AEAD crypto object for encryption-mode
+ * @krb5: The encoding to use.
+ * @TK: The transport key to use.
+ * @usage: The usage constant for key derivation.
+ * @gfp: Allocation flags.
+ *
+ * Allocate a crypto object that does all the necessary crypto, key it and set
+ * its parameters and return the crypto handle to it.  This can then be used to
+ * dispatch encrypt and decrypt operations.
+ */
+struct crypto_aead *crypto_krb5_prepare_encryption(const struct krb5_enctype *krb5,
+						   const struct krb5_buffer *TK,
+						   u32 usage, gfp_t gfp)
+{
+	struct crypto_aead *ci = NULL;
+	struct krb5_buffer keys = {};
+	int ret;
+
+	ret = krb5->profile->derive_encrypt_keys(krb5, TK, usage, &keys, gfp);
+	if (ret < 0)
+		goto err;
+
+	ci = krb5_prepare_encryption(krb5, &keys, gfp);
+	if (IS_ERR(ci)) {
+		ret = PTR_ERR(ci);
+		goto err;
+	}
+
+	kfree(keys.data);
+	return ci;
+err:
+	kfree(keys.data);
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(crypto_krb5_prepare_encryption);
+
+/*
+ * Prepare the checksum with derived key data.
+ */
+struct crypto_shash *krb5_prepare_checksum(const struct krb5_enctype *krb5,
+					   const struct krb5_buffer *Kc,
+					   gfp_t gfp)
+{
+	struct crypto_shash *ci = NULL;
+	int ret = -ENOMEM;
+
+	ci = crypto_alloc_shash(krb5->cksum_name, 0, 0);
+	if (IS_ERR(ci)) {
+		ret = PTR_ERR(ci);
+		if (ret == -ENOENT)
+			ret = -ENOPKG;
+		goto err;
+	}
+
+	ret = crypto_shash_setkey(ci, Kc->data, Kc->len);
+	if (ret < 0) {
+		pr_err("Couldn't set shash key %s: %d\n", krb5->cksum_name, ret);
+		goto err_ci;
+	}
+
+	return ci;
+err_ci:
+	crypto_free_shash(ci);
+err:
+	return ERR_PTR(ret);
+}
+
+/**
+ * crypto_krb5_prepare_checksum - Prepare AEAD crypto object for checksum-mode
+ * @krb5: The encoding to use.
+ * @TK: The transport key to use.
+ * @usage: The usage constant for key derivation.
+ * @gfp: Allocation flags.
+ *
+ * Allocate a crypto object that does all the necessary crypto, key it and set
+ * its parameters and return the crypto handle to it.  This can then be used to
+ * dispatch get_mic and verify_mic operations.
+ */
+struct crypto_shash *crypto_krb5_prepare_checksum(const struct krb5_enctype *krb5,
+						  const struct krb5_buffer *TK,
+						  u32 usage, gfp_t gfp)
+{
+	struct crypto_shash *ci = NULL;
+	struct krb5_buffer keys = {};
+	int ret;
+
+	ret = krb5->profile->derive_checksum_key(krb5, TK, usage, &keys, gfp);
+	if (ret < 0) {
+		pr_err("get_Kc failed %d\n", ret);
+		goto err;
+	}
+
+	ci = krb5_prepare_checksum(krb5, &keys, gfp);
+	if (IS_ERR(ci)) {
+		ret = PTR_ERR(ci);
+		goto err;
+	}
+
+	kfree(keys.data);
+	return ci;
+err:
+	kfree(keys.data);
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(crypto_krb5_prepare_checksum);
diff --git a/include/crypto/krb5.h b/include/crypto/krb5.h
index e7dfe0b7c60d..5ff052e2c157 100644
--- a/include/crypto/krb5.h
+++ b/include/crypto/krb5.h
@@ -10,6 +10,7 @@
 
 #include <linux/crypto.h>
 #include <crypto/aead.h>
+#include <crypto/hash.h>
 
 struct crypto_shash;
 struct scatterlist;
@@ -110,6 +111,12 @@ size_t crypto_krb5_how_much_data(const struct krb5_enctype *krb5,
 void crypto_krb5_where_is_the_data(const struct krb5_enctype *krb5,
 				   enum krb5_crypto_mode mode,
 				   size_t *_offset, size_t *_len);
+struct crypto_aead *crypto_krb5_prepare_encryption(const struct krb5_enctype *krb5,
+						   const struct krb5_buffer *TK,
+						   u32 usage, gfp_t gfp);
+struct crypto_shash *crypto_krb5_prepare_checksum(const struct krb5_enctype *krb5,
+						  const struct krb5_buffer *TK,
+						  u32 usage, gfp_t gfp);
 
 /*
  * krb5enc.c

[RFC PATCH 08/24] crypto/krb5: Add an API to perform requests

[David Howells]

Add an API by which users of the krb5 crypto library can perform crypto
requests, such as encrypt, decrypt, get_mic and verify_mic.  These
functions take the previously prepared crypto objects to work on.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/krb5/krb5_api.c | 141 +++++++++++++++++++++++++++++++++++++++++
 include/crypto/krb5.h  |  21 ++++++
 2 files changed, 162 insertions(+)

diff --git a/crypto/krb5/krb5_api.c b/crypto/krb5/krb5_api.c
index f7f2528b3895..8fc3a1b9d4ad 100644
--- a/crypto/krb5/krb5_api.c
+++ b/crypto/krb5/krb5_api.c
@@ -292,3 +292,144 @@ struct crypto_shash *crypto_krb5_prepare_checksum(const struct krb5_enctype *krb
 	return ERR_PTR(ret);
 }
 EXPORT_SYMBOL(crypto_krb5_prepare_checksum);
+
+/**
+ * crypto_krb5_encrypt - Apply Kerberos encryption and integrity.
+ * @krb5: The encoding to use.
+ * @aead: The keyed crypto object to use.
+ * @sg: Scatterlist defining the crypto buffer.
+ * @nr_sg: The number of elements in @sg.
+ * @sg_len: The size of the buffer.
+ * @data_offset: The offset of the data in the @sg buffer.
+ * @data_len: The length of the data.
+ * @preconfounded: True if the confounder is already inserted.
+ *
+ * Using the specified Kerberos encoding, insert a confounder and padding as
+ * needed, encrypt this and the data in place and insert an integrity checksum
+ * into the buffer.
+ *
+ * The buffer must include space for the confounder, the checksum and any
+ * padding required.  The caller can preinsert the confounder into the buffer
+ * (for testing, for example).
+ *
+ * The resulting secured blob may be less than the size of the buffer.
+ *
+ * Returns the size of the secure blob if successful, -ENOMEM on an allocation
+ * failure, -EFAULT if there is insufficient space, -EMSGSIZE if the confounder
+ * is too short or the data is misaligned.  Other errors may also be returned
+ * from the crypto layer.
+ */
+ssize_t crypto_krb5_encrypt(const struct krb5_enctype *krb5,
+			    struct crypto_aead *aead,
+			    struct scatterlist *sg, unsigned int nr_sg,
+			    size_t sg_len,
+			    size_t data_offset, size_t data_len,
+			    bool preconfounded)
+{
+	if (WARN_ON(data_offset > sg_len ||
+		    data_len > sg_len ||
+		    data_offset > sg_len - data_len))
+		return -EMSGSIZE;
+	return krb5->profile->encrypt(krb5, aead, sg, nr_sg, sg_len,
+				      data_offset, data_len, preconfounded);
+}
+EXPORT_SYMBOL(crypto_krb5_encrypt);
+
+/**
+ * crypto_krb5_decrypt - Validate and remove Kerberos encryption and integrity.
+ * @krb5: The encoding to use.
+ * @aead: The keyed crypto object to use.
+ * @sg: Scatterlist defining the crypto buffer.
+ * @nr_sg: The number of elements in @sg.
+ * @_offset: Offset of the secure blob in the buffer; updated to data offset.
+ * @_len: The length of the secure blob; updated to data length.
+ *
+ * Using the specified Kerberos encoding, check and remove the integrity
+ * checksum and decrypt the secure region, stripping off the confounder.
+ *
+ * If successful, @_offset and @_len are updated to outline the region in which
+ * the data plus the trailing padding are stored.  The caller is responsible
+ * for working out how much padding there is and removing it.
+ *
+ * Returns the 0 if successful, -ENOMEM on an allocation failure; sets
+ * *_error_code and returns -EPROTO if the data cannot be parsed, or -EBADMSG
+ * if the integrity checksum doesn't match).  Other errors may also be returned
+ * from the crypto layer.
+ */
+int crypto_krb5_decrypt(const struct krb5_enctype *krb5,
+			struct crypto_aead *aead,
+			struct scatterlist *sg, unsigned int nr_sg,
+			size_t *_offset, size_t *_len)
+{
+	return krb5->profile->decrypt(krb5, aead, sg, nr_sg, _offset, _len);
+}
+EXPORT_SYMBOL(crypto_krb5_decrypt);
+
+/**
+ * crypto_krb5_get_mic - Apply Kerberos integrity checksum.
+ * @krb5: The encoding to use.
+ * @shash: The keyed hash to use.
+ * @metadata: Metadata to add into the hash before adding the data.
+ * @sg: Scatterlist defining the crypto buffer.
+ * @nr_sg: The number of elements in @sg.
+ * @sg_len: The size of the buffer.
+ * @data_offset: The offset of the data in the @sg buffer.
+ * @data_len: The length of the data.
+ *
+ * Using the specified Kerberos encoding, calculate and insert an integrity
+ * checksum into the buffer.
+ *
+ * The buffer must include space for the checksum at the front.
+ *
+ * Returns the size of the secure blob if successful, -ENOMEM on an allocation
+ * failure, -EFAULT if there is insufficient space, -EMSGSIZE if the gap for
+ * the checksum is too short.  Other errors may also be returned from the
+ * crypto layer.
+ */
+ssize_t crypto_krb5_get_mic(const struct krb5_enctype *krb5,
+			    struct crypto_shash *shash,
+			    const struct krb5_buffer *metadata,
+			    struct scatterlist *sg, unsigned int nr_sg,
+			    size_t sg_len,
+			    size_t data_offset, size_t data_len)
+{
+	if (WARN_ON(data_offset > sg_len ||
+		    data_len > sg_len ||
+		    data_offset > sg_len - data_len))
+		return -EMSGSIZE;
+	return krb5->profile->get_mic(krb5, shash, metadata, sg, nr_sg, sg_len,
+				      data_offset, data_len);
+}
+EXPORT_SYMBOL(crypto_krb5_get_mic);
+
+/**
+ * crypto_krb5_verify_mic - Validate and remove Kerberos integrity checksum.
+ * @krb5: The encoding to use.
+ * @shash: The keyed hash to use.
+ * @metadata: Metadata to add into the hash before adding the data.
+ * @sg: Scatterlist defining the crypto buffer.
+ * @nr_sg: The number of elements in @sg.
+ * @_offset: Offset of the secure blob in the buffer; updated to data offset.
+ * @_len: The length of the secure blob; updated to data length.
+ *
+ * Using the specified Kerberos encoding, check and remove the integrity
+ * checksum.
+ *
+ * If successful, @_offset and @_len are updated to outline the region in which
+ * the data is stored.
+ *
+ * Returns the 0 if successful, -ENOMEM on an allocation failure; sets
+ * *_error_code and returns -EPROTO if the data cannot be parsed, or -EBADMSG
+ * if the checksum doesn't match).  Other errors may also be returned from the
+ * crypto layer.
+ */
+int crypto_krb5_verify_mic(const struct krb5_enctype *krb5,
+			   struct crypto_shash *shash,
+			   const struct krb5_buffer *metadata,
+			   struct scatterlist *sg, unsigned int nr_sg,
+			   size_t *_offset, size_t *_len)
+{
+	return krb5->profile->verify_mic(krb5, shash, metadata, sg, nr_sg,
+					 _offset, _len);
+}
+EXPORT_SYMBOL(crypto_krb5_verify_mic);
diff --git a/include/crypto/krb5.h b/include/crypto/krb5.h
index 5ff052e2c157..4919e135b2ca 100644
--- a/include/crypto/krb5.h
+++ b/include/crypto/krb5.h
@@ -117,6 +117,27 @@ struct crypto_aead *crypto_krb5_prepare_encryption(const struct krb5_enctype *kr
 struct crypto_shash *crypto_krb5_prepare_checksum(const struct krb5_enctype *krb5,
 						  const struct krb5_buffer *TK,
 						  u32 usage, gfp_t gfp);
+ssize_t crypto_krb5_encrypt(const struct krb5_enctype *krb5,
+			    struct crypto_aead *aead,
+			    struct scatterlist *sg, unsigned int nr_sg,
+			    size_t sg_len,
+			    size_t data_offset, size_t data_len,
+			    bool preconfounded);
+int crypto_krb5_decrypt(const struct krb5_enctype *krb5,
+			struct crypto_aead *aead,
+			struct scatterlist *sg, unsigned int nr_sg,
+			size_t *_offset, size_t *_len);
+ssize_t crypto_krb5_get_mic(const struct krb5_enctype *krb5,
+			    struct crypto_shash *shash,
+			    const struct krb5_buffer *metadata,
+			    struct scatterlist *sg, unsigned int nr_sg,
+			    size_t sg_len,
+			    size_t data_offset, size_t data_len);
+int crypto_krb5_verify_mic(const struct krb5_enctype *krb5,
+			   struct crypto_shash *shash,
+			   const struct krb5_buffer *metadata,
+			   struct scatterlist *sg, unsigned int nr_sg,
+			   size_t *_offset, size_t *_len);
 
 /*
  * krb5enc.c

[RFC PATCH 09/24] crypto/krb5: Provide infrastructure and key derivation

[David Howells]

Provide key derivation interface functions and a helper to implement the
PRF+ function from rfc4402.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/krb5/Makefile   |   1 +
 crypto/krb5/internal.h |  10 +++
 crypto/krb5/krb5_kdf.c | 145 +++++++++++++++++++++++++++++++++++++++++
 include/crypto/krb5.h  |  10 +++
 4 files changed, 166 insertions(+)
 create mode 100644 crypto/krb5/krb5_kdf.c

diff --git a/crypto/krb5/Makefile b/crypto/krb5/Makefile
index c450d0754772..8c2050af8fed 100644
--- a/crypto/krb5/Makefile
+++ b/crypto/krb5/Makefile
@@ -4,6 +4,7 @@
 #
 
 krb5-y += \
+	krb5_kdf.o \
 	krb5_api.o
 
 obj-$(CONFIG_CRYPTO_KRB5) += krb5.o
diff --git a/crypto/krb5/internal.h b/crypto/krb5/internal.h
index b542d24e5fa5..50abda5169c7 100644
--- a/crypto/krb5/internal.h
+++ b/crypto/krb5/internal.h
@@ -120,3 +120,13 @@ struct crypto_aead *krb5_prepare_encryption(const struct krb5_enctype *krb5,
 struct crypto_shash *krb5_prepare_checksum(const struct krb5_enctype *krb5,
 					   const struct krb5_buffer *Kc,
 					   gfp_t gfp);
+
+/*
+ * krb5_kdf.c
+ */
+int krb5_derive_Kc(const struct krb5_enctype *krb5, const struct krb5_buffer *TK,
+		   u32 usage, struct krb5_buffer *key, gfp_t gfp);
+int krb5_derive_Ke(const struct krb5_enctype *krb5, const struct krb5_buffer *TK,
+		   u32 usage, struct krb5_buffer *key, gfp_t gfp);
+int krb5_derive_Ki(const struct krb5_enctype *krb5, const struct krb5_buffer *TK,
+		   u32 usage, struct krb5_buffer *key, gfp_t gfp);
diff --git a/crypto/krb5/krb5_kdf.c b/crypto/krb5/krb5_kdf.c
new file mode 100644
index 000000000000..6699e5469d1b
--- /dev/null
+++ b/crypto/krb5/krb5_kdf.c
@@ -0,0 +1,145 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Kerberos key derivation.
+ *
+ * Copyright (C) 2025 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/export.h>
+#include <linux/slab.h>
+#include <crypto/skcipher.h>
+#include <crypto/hash.h>
+#include "internal.h"
+
+/**
+ * crypto_krb5_calc_PRFplus - Calculate PRF+ [RFC4402]
+ * @krb5: The encryption type to use
+ * @K: The protocol key for the pseudo-random function
+ * @L: The length of the output
+ * @S: The input octet string
+ * @result: Result buffer, sized to krb5->prf_len
+ * @gfp: Allocation restrictions
+ *
+ * Calculate the kerberos pseudo-random function, PRF+() by the following
+ * method:
+ *
+ *      PRF+(K, L, S) = truncate(L, T1 || T2 || .. || Tn)
+ *      Tn = PRF(K, n || S)
+ *      [rfc4402 sec 2]
+ */
+int crypto_krb5_calc_PRFplus(const struct krb5_enctype *krb5,
+			     const struct krb5_buffer *K,
+			     unsigned int L,
+			     const struct krb5_buffer *S,
+			     struct krb5_buffer *result,
+			     gfp_t gfp)
+{
+	struct krb5_buffer T_series, Tn, n_S;
+	void *buffer;
+	int ret, n = 1;
+
+	Tn.len = krb5->prf_len;
+	T_series.len = 0;
+	n_S.len = 4 + S->len;
+
+	buffer = kzalloc(round16(L + Tn.len) + round16(n_S.len), gfp);
+	if (!buffer)
+		return -ENOMEM;
+
+	T_series.data = buffer;
+	n_S.data = buffer + round16(L + Tn.len);
+	memcpy(n_S.data + 4, S->data, S->len);
+
+	while (T_series.len < L) {
+		*(__be32 *)(n_S.data) = htonl(n);
+		Tn.data = T_series.data + Tn.len * (n - 1);
+		ret = krb5->profile->calc_PRF(krb5, K, &n_S, &Tn, gfp);
+		if (ret < 0)
+			goto err;
+		T_series.len += Tn.len;
+		n++;
+	}
+
+	/* Truncate to L */
+	memcpy(result->data, T_series.data, L);
+	ret = 0;
+
+err:
+	kfree_sensitive(buffer);
+	return ret;
+}
+EXPORT_SYMBOL(crypto_krb5_calc_PRFplus);
+
+/**
+ * krb5_derive_Kc - Derive key Kc and install into a hash
+ * @krb5: The encryption type to use
+ * @TK: The base key
+ * @usage: The key usage number
+ * @key: Prepped buffer to store the key into
+ * @gfp: Allocation restrictions
+ *
+ * Derive the Kerberos Kc checksumming key.  The key is stored into the
+ * prepared buffer.
+ */
+int krb5_derive_Kc(const struct krb5_enctype *krb5, const struct krb5_buffer *TK,
+		   u32 usage, struct krb5_buffer *key, gfp_t gfp)
+{
+	u8 buf[5] __aligned(CRYPTO_MINALIGN);
+	struct krb5_buffer usage_constant = { .len = 5, .data = buf };
+
+	*(__be32 *)buf = cpu_to_be32(usage);
+	buf[4] = KEY_USAGE_SEED_CHECKSUM;
+
+	key->len = krb5->Kc_len;
+	return krb5->profile->calc_Kc(krb5, TK, &usage_constant, key, gfp);
+}
+
+/**
+ * krb5_derive_Ke - Derive key Ke and install into an skcipher
+ * @krb5: The encryption type to use
+ * @TK: The base key
+ * @usage: The key usage number
+ * @key: Prepped buffer to store the key into
+ * @gfp: Allocation restrictions
+ *
+ * Derive the Kerberos Ke encryption key.  The key is stored into the prepared
+ * buffer.
+ */
+int krb5_derive_Ke(const struct krb5_enctype *krb5, const struct krb5_buffer *TK,
+		   u32 usage, struct krb5_buffer *key, gfp_t gfp)
+{
+	u8 buf[5] __aligned(CRYPTO_MINALIGN);
+	struct krb5_buffer usage_constant = { .len = 5, .data = buf };
+
+	*(__be32 *)buf = cpu_to_be32(usage);
+	buf[4] = KEY_USAGE_SEED_ENCRYPTION;
+
+	key->len = krb5->Ke_len;
+	return krb5->profile->calc_Ke(krb5, TK, &usage_constant, key, gfp);
+}
+
+/**
+ * krb5_derive_Ki - Derive key Ki and install into a hash
+ * @krb5: The encryption type to use
+ * @TK: The base key
+ * @usage: The key usage number
+ * @key: Prepped buffer to store the key into
+ * @gfp: Allocation restrictions
+ *
+ * Derive the Kerberos Ki integrity checksum key.  The key is stored into the
+ * prepared buffer.
+ */
+int krb5_derive_Ki(const struct krb5_enctype *krb5, const struct krb5_buffer *TK,
+		   u32 usage, struct krb5_buffer *key, gfp_t gfp)
+{
+	u8 buf[5] __aligned(CRYPTO_MINALIGN);
+	struct krb5_buffer usage_constant = { .len = 5, .data = buf };
+
+	*(__be32 *)buf = cpu_to_be32(usage);
+	buf[4] = KEY_USAGE_SEED_INTEGRITY;
+
+	key->len = krb5->Ki_len;
+	return krb5->profile->calc_Ki(krb5, TK, &usage_constant, key, gfp);
+}
diff --git a/include/crypto/krb5.h b/include/crypto/krb5.h
index 4919e135b2ca..a24d9ee53675 100644
--- a/include/crypto/krb5.h
+++ b/include/crypto/krb5.h
@@ -139,6 +139,16 @@ int crypto_krb5_verify_mic(const struct krb5_enctype *krb5,
 			   struct scatterlist *sg, unsigned int nr_sg,
 			   size_t *_offset, size_t *_len);
 
+/*
+ * krb5_kdf.c
+ */
+int crypto_krb5_calc_PRFplus(const struct krb5_enctype *krb5,
+			     const struct krb5_buffer *K,
+			     unsigned int L,
+			     const struct krb5_buffer *S,
+			     struct krb5_buffer *result,
+			     gfp_t gfp);
+
 /*
  * krb5enc.c
  */

[RFC PATCH 10/24] crypto/krb5: Implement the Kerberos5 rfc3961 key derivation

[David Howells]

Implement the simplified crypto profile for Kerberos 5 rfc3961 with the
pseudo-random function, PRF(), from section 5.3 and the key derivation
function, DK() from section 5.1.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/krb5/Makefile             |   3 +-
 crypto/krb5/internal.h           |   6 +
 crypto/krb5/rfc3961_simplified.c | 407 +++++++++++++++++++++++++++++++
 3 files changed, 415 insertions(+), 1 deletion(-)
 create mode 100644 crypto/krb5/rfc3961_simplified.c

diff --git a/crypto/krb5/Makefile b/crypto/krb5/Makefile
index 8c2050af8fed..8dad8e3bf086 100644
--- a/crypto/krb5/Makefile
+++ b/crypto/krb5/Makefile
@@ -5,6 +5,7 @@
 
 krb5-y += \
 	krb5_kdf.o \
-	krb5_api.o
+	krb5_api.o \
+	rfc3961_simplified.o
 
 obj-$(CONFIG_CRYPTO_KRB5) += krb5.o
diff --git a/crypto/krb5/internal.h b/crypto/krb5/internal.h
index 50abda5169c7..7d60977dc0c5 100644
--- a/crypto/krb5/internal.h
+++ b/crypto/krb5/internal.h
@@ -5,6 +5,7 @@
  * Written by David Howells (dhowells@redhat.com)
  */
 
+#include <linux/scatterlist.h>
 #include <crypto/krb5.h>
 
 /*
@@ -130,3 +131,8 @@ int krb5_derive_Ke(const struct krb5_enctype *krb5, const struct krb5_buffer *TK
 		   u32 usage, struct krb5_buffer *key, gfp_t gfp);
 int krb5_derive_Ki(const struct krb5_enctype *krb5, const struct krb5_buffer *TK,
 		   u32 usage, struct krb5_buffer *key, gfp_t gfp);
+
+/*
+ * rfc3961_simplified.c
+ */
+extern const struct krb5_crypto_profile rfc3961_simplified_profile;
diff --git a/crypto/krb5/rfc3961_simplified.c b/crypto/krb5/rfc3961_simplified.c
new file mode 100644
index 000000000000..492ad85cdd56
--- /dev/null
+++ b/crypto/krb5/rfc3961_simplified.c
@@ -0,0 +1,407 @@
+// SPDX-License-Identifier: BSD-3-Clause
+/* rfc3961 Kerberos 5 simplified crypto profile.
+ *
+ * Parts borrowed from net/sunrpc/auth_gss/.
+ */
+/*
+ * COPYRIGHT (c) 2008
+ * The Regents of the University of Michigan
+ * ALL RIGHTS RESERVED
+ *
+ * Permission is granted to use, copy, create derivative works
+ * and redistribute this software and such derivative works
+ * for any purpose, so long as the name of The University of
+ * Michigan is not used in any advertising or publicity
+ * pertaining to the use of distribution of this software
+ * without specific, written prior authorization.  If the
+ * above copyright notice or any other identification of the
+ * University of Michigan is included in any copy of any
+ * portion of this software, then the disclaimer below must
+ * also be included.
+ *
+ * THIS SOFTWARE IS PROVIDED AS IS, WITHOUT REPRESENTATION
+ * FROM THE UNIVERSITY OF MICHIGAN AS TO ITS FITNESS FOR ANY
+ * PURPOSE, AND WITHOUT WARRANTY BY THE UNIVERSITY OF
+ * MICHIGAN OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING
+ * WITHOUT LIMITATION THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
+ * REGENTS OF THE UNIVERSITY OF MICHIGAN SHALL NOT BE LIABLE
+ * FOR ANY DAMAGES, INCLUDING SPECIAL, INDIRECT, INCIDENTAL, OR
+ * CONSEQUENTIAL DAMAGES, WITH RESPECT TO ANY CLAIM ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OF THE SOFTWARE, EVEN
+ * IF IT HAS BEEN OR IS HEREAFTER ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGES.
+ */
+
+/*
+ * Copyright (C) 1998 by the FundsXpress, INC.
+ *
+ * All rights reserved.
+ *
+ * Export of this software from the United States of America may require
+ * a specific license from the United States Government.  It is the
+ * responsibility of any person or organization contemplating export to
+ * obtain such a license before exporting.
+ *
+ * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
+ * distribute this software and its documentation for any purpose and
+ * without fee is hereby granted, provided that the above copyright
+ * notice appear in all copies and that both that copyright notice and
+ * this permission notice appear in supporting documentation, and that
+ * the name of FundsXpress. not be used in advertising or publicity pertaining
+ * to distribution of the software without specific, written prior
+ * permission.  FundsXpress makes no representations about the suitability of
+ * this software for any purpose.  It is provided "as is" without express
+ * or implied warranty.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+/*
+ * Copyright (C) 2025 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/slab.h>
+#include <linux/lcm.h>
+#include <crypto/skcipher.h>
+#include <crypto/hash.h>
+#include "internal.h"
+
+/* Maximum blocksize for the supported crypto algorithms */
+#define KRB5_MAX_BLOCKSIZE  (16)
+
+static int rfc3961_do_encrypt(struct crypto_sync_skcipher *tfm, void *iv,
+			      const struct krb5_buffer *in, struct krb5_buffer *out)
+{
+	struct scatterlist sg[1];
+	u8 local_iv[KRB5_MAX_BLOCKSIZE] __aligned(KRB5_MAX_BLOCKSIZE) = {0};
+	SYNC_SKCIPHER_REQUEST_ON_STACK(req, tfm);
+	int ret;
+
+	if (WARN_ON(in->len != out->len))
+		return -EINVAL;
+	if (out->len % crypto_sync_skcipher_blocksize(tfm) != 0)
+		return -EINVAL;
+
+	if (crypto_sync_skcipher_ivsize(tfm) > KRB5_MAX_BLOCKSIZE)
+		return -EINVAL;
+
+	if (iv)
+		memcpy(local_iv, iv, crypto_sync_skcipher_ivsize(tfm));
+
+	memcpy(out->data, in->data, out->len);
+	sg_init_one(sg, out->data, out->len);
+
+	skcipher_request_set_sync_tfm(req, tfm);
+	skcipher_request_set_callback(req, 0, NULL, NULL);
+	skcipher_request_set_crypt(req, sg, sg, out->len, local_iv);
+
+	ret = crypto_skcipher_encrypt(req);
+	skcipher_request_zero(req);
+	return ret;
+}
+
+/*
+ * Calculate an unkeyed basic hash.
+ */
+static int rfc3961_calc_H(const struct krb5_enctype *krb5,
+			  const struct krb5_buffer *data,
+			  struct krb5_buffer *digest,
+			  gfp_t gfp)
+{
+	struct crypto_shash *tfm;
+	struct shash_desc *desc;
+	size_t desc_size;
+	int ret = -ENOMEM;
+
+	tfm = crypto_alloc_shash(krb5->hash_name, 0, 0);
+	if (IS_ERR(tfm))
+		return (PTR_ERR(tfm) == -ENOENT) ? -ENOPKG : PTR_ERR(tfm);
+
+	desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
+
+	desc = kzalloc(desc_size, gfp);
+	if (!desc)
+		goto error_tfm;
+
+	digest->len = crypto_shash_digestsize(tfm);
+	digest->data = kzalloc(digest->len, gfp);
+	if (!digest->data)
+		goto error_desc;
+
+	desc->tfm = tfm;
+	ret = crypto_shash_init(desc);
+	if (ret < 0)
+		goto error_digest;
+
+	ret = crypto_shash_finup(desc, data->data, data->len, digest->data);
+	if (ret < 0)
+		goto error_digest;
+
+	goto error_desc;
+
+error_digest:
+	kfree_sensitive(digest->data);
+error_desc:
+	kfree_sensitive(desc);
+error_tfm:
+	crypto_free_shash(tfm);
+	return ret;
+}
+
+/*
+ * This is the n-fold function as described in rfc3961, sec 5.1
+ * Taken from MIT Kerberos and modified.
+ */
+static void rfc3961_nfold(const struct krb5_buffer *source, struct krb5_buffer *result)
+{
+	const u8 *in = source->data;
+	u8 *out = result->data;
+	unsigned long ulcm;
+	unsigned int inbits, outbits;
+	int byte, i, msbit;
+
+	/* the code below is more readable if I make these bytes instead of bits */
+	inbits = source->len;
+	outbits = result->len;
+
+	/* first compute lcm(n,k) */
+	ulcm = lcm(inbits, outbits);
+
+	/* now do the real work */
+	memset(out, 0, outbits);
+	byte = 0;
+
+	/* this will end up cycling through k lcm(k,n)/k times, which
+	 * is correct.
+	 */
+	for (i = ulcm-1; i >= 0; i--) {
+		/* compute the msbit in k which gets added into this byte */
+		msbit = (
+			/* first, start with the msbit in the first,
+			 * unrotated byte
+			 */
+			((inbits << 3) - 1) +
+			/* then, for each byte, shift to the right
+			 * for each repetition
+			 */
+			(((inbits << 3) + 13) * (i/inbits)) +
+			/* last, pick out the correct byte within
+			 * that shifted repetition
+			 */
+			((inbits - (i % inbits)) << 3)
+			 ) % (inbits << 3);
+
+		/* pull out the byte value itself */
+		byte += (((in[((inbits - 1) - (msbit >> 3)) % inbits] << 8) |
+			  (in[((inbits)     - (msbit >> 3)) % inbits]))
+			 >> ((msbit & 7) + 1)) & 0xff;
+
+		/* do the addition */
+		byte += out[i % outbits];
+		out[i % outbits] = byte & 0xff;
+
+		/* keep around the carry bit, if any */
+		byte >>= 8;
+	}
+
+	/* if there's a carry bit left over, add it back in */
+	if (byte) {
+		for (i = outbits - 1; i >= 0; i--) {
+			/* do the addition */
+			byte += out[i];
+			out[i] = byte & 0xff;
+
+			/* keep around the carry bit, if any */
+			byte >>= 8;
+		}
+	}
+}
+
+/*
+ * Calculate a derived key, DK(Base Key, Well-Known Constant)
+ *
+ * DK(Key, Constant) = random-to-key(DR(Key, Constant))
+ * DR(Key, Constant) = k-truncate(E(Key, Constant, initial-cipher-state))
+ * K1 = E(Key, n-fold(Constant), initial-cipher-state)
+ * K2 = E(Key, K1, initial-cipher-state)
+ * K3 = E(Key, K2, initial-cipher-state)
+ * K4 = ...
+ * DR(Key, Constant) = k-truncate(K1 | K2 | K3 | K4 ...)
+ * [rfc3961 sec 5.1]
+ */
+static int rfc3961_calc_DK(const struct krb5_enctype *krb5,
+			   const struct krb5_buffer *inkey,
+			   const struct krb5_buffer *in_constant,
+			   struct krb5_buffer *result,
+			   gfp_t gfp)
+{
+	unsigned int blocksize, keybytes, keylength, n;
+	struct krb5_buffer inblock, outblock, rawkey;
+	struct crypto_sync_skcipher *cipher;
+	int ret = -EINVAL;
+
+	blocksize = krb5->block_len;
+	keybytes = krb5->key_bytes;
+	keylength = krb5->key_len;
+
+	if (inkey->len != keylength || result->len != keylength)
+		return -EINVAL;
+	if (!krb5->random_to_key && result->len != keybytes)
+		ret = -EINVAL;
+
+	cipher = crypto_alloc_sync_skcipher(krb5->derivation_enc, 0, 0);
+	if (IS_ERR(cipher)) {
+		ret = (PTR_ERR(cipher) == -ENOENT) ? -ENOPKG : PTR_ERR(cipher);
+		goto err_return;
+	}
+	ret = crypto_sync_skcipher_setkey(cipher, inkey->data, inkey->len);
+	if (ret < 0)
+		goto err_free_cipher;
+
+	ret = -ENOMEM;
+	inblock.data = kzalloc(blocksize * 2 + keybytes, gfp);
+	if (!inblock.data)
+		goto err_free_cipher;
+
+	inblock.len	= blocksize;
+	outblock.data	= inblock.data + blocksize;
+	outblock.len	= blocksize;
+	rawkey.data	= outblock.data + blocksize;
+	rawkey.len	= keybytes;
+
+	/* initialize the input block */
+
+	if (in_constant->len == inblock.len)
+		memcpy(inblock.data, in_constant->data, inblock.len);
+	else
+		rfc3961_nfold(in_constant, &inblock);
+
+	/* loop encrypting the blocks until enough key bytes are generated */
+	n = 0;
+	while (n < rawkey.len) {
+		rfc3961_do_encrypt(cipher, NULL, &inblock, &outblock);
+
+		if (keybytes - n <= outblock.len) {
+			memcpy(rawkey.data + n, outblock.data, keybytes - n);
+			break;
+		}
+
+		memcpy(rawkey.data + n, outblock.data, outblock.len);
+		memcpy(inblock.data, outblock.data, outblock.len);
+		n += outblock.len;
+	}
+
+	/* postprocess the key */
+	if (!krb5->random_to_key) {
+		/* Identity random-to-key function. */
+		memcpy(result->data, rawkey.data, rawkey.len);
+		ret = 0;
+	} else {
+		ret = krb5->random_to_key(krb5, &rawkey, result);
+	}
+
+	kfree_sensitive(inblock.data);
+err_free_cipher:
+	crypto_free_sync_skcipher(cipher);
+err_return:
+	return ret;
+}
+
+/*
+ * Calculate single encryption, E()
+ *
+ *	E(Key, octets)
+ */
+static int rfc3961_calc_E(const struct krb5_enctype *krb5,
+			  const struct krb5_buffer *key,
+			  const struct krb5_buffer *in_data,
+			  struct krb5_buffer *result,
+			  gfp_t gfp)
+{
+	struct crypto_sync_skcipher *cipher;
+	int ret;
+
+	cipher = crypto_alloc_sync_skcipher(krb5->derivation_enc, 0, 0);
+	if (IS_ERR(cipher)) {
+		ret = (PTR_ERR(cipher) == -ENOENT) ? -ENOPKG : PTR_ERR(cipher);
+		goto err;
+	}
+
+	ret = crypto_sync_skcipher_setkey(cipher, key->data, key->len);
+	if (ret < 0)
+		goto err_free;
+
+	ret = rfc3961_do_encrypt(cipher, NULL, in_data, result);
+
+err_free:
+	crypto_free_sync_skcipher(cipher);
+err:
+	return ret;
+}
+
+/*
+ * Calculate the pseudo-random function, PRF().
+ *
+ *      tmp1 = H(octet-string)
+ *      tmp2 = truncate tmp1 to multiple of m
+ *      PRF = E(DK(protocol-key, prfconstant), tmp2, initial-cipher-state)
+ *
+ *      The "prfconstant" used in the PRF operation is the three-octet string
+ *      "prf".
+ *      [rfc3961 sec 5.3]
+ */
+static int rfc3961_calc_PRF(const struct krb5_enctype *krb5,
+			    const struct krb5_buffer *protocol_key,
+			    const struct krb5_buffer *octet_string,
+			    struct krb5_buffer *result,
+			    gfp_t gfp)
+{
+	static const struct krb5_buffer prfconstant = { 3, "prf" };
+	struct krb5_buffer derived_key;
+	struct krb5_buffer tmp1, tmp2;
+	unsigned int m = krb5->block_len;
+	void *buffer;
+	int ret;
+
+	if (result->len != krb5->prf_len)
+		return -EINVAL;
+
+	tmp1.len = krb5->hash_len;
+	derived_key.len = krb5->key_bytes;
+	buffer = kzalloc(round16(tmp1.len) + round16(derived_key.len), gfp);
+	if (!buffer)
+		return -ENOMEM;
+
+	tmp1.data = buffer;
+	derived_key.data = buffer + round16(tmp1.len);
+
+	ret = rfc3961_calc_H(krb5, octet_string, &tmp1, gfp);
+	if (ret < 0)
+		goto err;
+
+	tmp2.len = tmp1.len & ~(m - 1);
+	tmp2.data = tmp1.data;
+
+	ret = rfc3961_calc_DK(krb5, protocol_key, &prfconstant, &derived_key, gfp);
+	if (ret < 0)
+		goto err;
+
+	ret = rfc3961_calc_E(krb5, &derived_key, &tmp2, result, gfp);
+
+err:
+	kfree_sensitive(buffer);
+	return ret;
+}
+
+const struct krb5_crypto_profile rfc3961_simplified_profile = {
+	.calc_PRF	= rfc3961_calc_PRF,
+	.calc_Kc	= rfc3961_calc_DK,
+	.calc_Ke	= rfc3961_calc_DK,
+	.calc_Ki	= rfc3961_calc_DK,
+};

[RFC PATCH 11/24] crypto/krb5: Provide RFC3961 setkey packaging functions

[David Howells]

Provide functions to derive keys according to RFC3961 (or load the derived
keys for the selftester where only derived keys are available) and to
package them up appropriately for passing to a krb5enc AEAD setkey or a
hash setkey function.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/krb5/internal.h           |  20 ++++++
 crypto/krb5/rfc3961_simplified.c | 116 +++++++++++++++++++++++++++++--
 2 files changed, 132 insertions(+), 4 deletions(-)

diff --git a/crypto/krb5/internal.h b/crypto/krb5/internal.h
index 7d60977dc0c5..8418c23d5018 100644
--- a/crypto/krb5/internal.h
+++ b/crypto/krb5/internal.h
@@ -136,3 +136,23 @@ int krb5_derive_Ki(const struct krb5_enctype *krb5, const struct krb5_buffer *TK
  * rfc3961_simplified.c
  */
 extern const struct krb5_crypto_profile rfc3961_simplified_profile;
+
+int krb5enc_derive_encrypt_keys(const struct krb5_enctype *krb5,
+				const struct krb5_buffer *TK,
+				unsigned int usage,
+				struct krb5_buffer *setkey,
+				gfp_t gfp);
+int krb5enc_load_encrypt_keys(const struct krb5_enctype *krb5,
+			      const struct krb5_buffer *Ke,
+			      const struct krb5_buffer *Ki,
+			      struct krb5_buffer *setkey,
+			      gfp_t gfp);
+int rfc3961_derive_checksum_key(const struct krb5_enctype *krb5,
+				const struct krb5_buffer *TK,
+				unsigned int usage,
+				struct krb5_buffer *setkey,
+				gfp_t gfp);
+int rfc3961_load_checksum_key(const struct krb5_enctype *krb5,
+			      const struct krb5_buffer *Kc,
+			      struct krb5_buffer *setkey,
+			      gfp_t gfp);
diff --git a/crypto/krb5/rfc3961_simplified.c b/crypto/krb5/rfc3961_simplified.c
index 492ad85cdd56..d25fbd574dde 100644
--- a/crypto/krb5/rfc3961_simplified.c
+++ b/crypto/krb5/rfc3961_simplified.c
@@ -399,9 +399,117 @@ static int rfc3961_calc_PRF(const struct krb5_enctype *krb5,
 	return ret;
 }
 
+/*
+ * Derive the Ke and Ki keys and package them into a key parameter that can be
+ * given to the setkey of a krb5enc AEAD crypto object.
+ */
+int krb5enc_derive_encrypt_keys(const struct krb5_enctype *krb5,
+				const struct krb5_buffer *TK,
+				unsigned int usage,
+				struct krb5_buffer *setkey,
+				gfp_t gfp)
+{
+	struct krb5_buffer Ke, Ki;
+	__be32 *khdr = NULL;
+	int ret;
+
+	Ke.len  = krb5->Ke_len;
+	Ki.len  = krb5->Ki_len;
+	setkey->len = sizeof(__be32) * 3 + krb5->Ke_len + krb5->Ki_len;
+	setkey->data = kzalloc(setkey->len, GFP_KERNEL);
+	if (!setkey->data)
+		return -ENOMEM;
+
+	khdr = setkey->data;
+	Ke.data = setkey->data + 12;
+	Ki.data = setkey->data + 12 + Ke.len;
+
+	khdr[0] = htonl(1); /* Format 1 */
+	khdr[1] = htonl(Ke.len);
+	khdr[2] = htonl(Ki.len);
+
+	ret = krb5_derive_Ke(krb5, TK, usage, &Ke, gfp);
+	if (ret < 0) {
+		pr_err("get_Ke failed %d\n", ret);
+		return ret;
+	}
+	ret = krb5_derive_Ki(krb5, TK, usage, &Ki, gfp);
+	if (ret < 0)
+		pr_err("get_Ki failed %d\n", ret);
+	return ret;
+}
+
+/*
+ * Package predefined Ke and Ki keys and into a key parameter that can be given
+ * to the setkey of a krb5enc AEAD crypto object.
+ */
+int krb5enc_load_encrypt_keys(const struct krb5_enctype *krb5,
+			      const struct krb5_buffer *Ke,
+			      const struct krb5_buffer *Ki,
+			      struct krb5_buffer *setkey,
+			      gfp_t gfp)
+{
+	__be32 *khdr = NULL;
+
+	setkey->len = sizeof(__be32) * 3 + Ke->len + Ki->len;
+	setkey->data = kzalloc(setkey->len, GFP_KERNEL);
+	if (!setkey->data)
+		return -ENOMEM;
+
+	khdr = setkey->data;
+	khdr[0] = htonl(1); /* Format 1 */
+	khdr[1] = htonl(Ke->len);
+	khdr[2] = htonl(Ki->len);
+	memcpy(setkey->data + 12, Ke->data, Ke->len);
+	memcpy(setkey->data + 12 + Ke->len, Ki->data, Ki->len);
+	return 0;
+}
+
+/*
+ * Derive the Kc key for checksum-only mode and package it into a key parameter
+ * that can be given to the setkey of a hash crypto object.
+ */
+int rfc3961_derive_checksum_key(const struct krb5_enctype *krb5,
+				const struct krb5_buffer *TK,
+				unsigned int usage,
+				struct krb5_buffer *setkey,
+				gfp_t gfp)
+{
+	int ret;
+
+	setkey->len = krb5->Kc_len;
+	setkey->data = kzalloc(setkey->len, GFP_KERNEL);
+	if (!setkey->data)
+		return -ENOMEM;
+
+	ret = krb5_derive_Kc(krb5, TK, usage, setkey, gfp);
+	if (ret < 0)
+		pr_err("get_Kc failed %d\n", ret);
+	return ret;
+}
+
+/*
+ * Package a predefined Kc key for checksum-only mode into a key parameter that
+ * can be given to the setkey of a hash crypto object.
+ */
+int rfc3961_load_checksum_key(const struct krb5_enctype *krb5,
+			      const struct krb5_buffer *Kc,
+			      struct krb5_buffer *setkey,
+			      gfp_t gfp)
+{
+	setkey->len = krb5->Kc_len;
+	setkey->data = kmemdup(Kc->data, Kc->len, GFP_KERNEL);
+	if (!setkey->data)
+		return -ENOMEM;
+	return 0;
+}
 const struct krb5_crypto_profile rfc3961_simplified_profile = {
-	.calc_PRF	= rfc3961_calc_PRF,
-	.calc_Kc	= rfc3961_calc_DK,
-	.calc_Ke	= rfc3961_calc_DK,
-	.calc_Ki	= rfc3961_calc_DK,
+	.calc_PRF		= rfc3961_calc_PRF,
+	.calc_Kc		= rfc3961_calc_DK,
+	.calc_Ke		= rfc3961_calc_DK,
+	.calc_Ki		= rfc3961_calc_DK,
+	.derive_encrypt_keys	= krb5enc_derive_encrypt_keys,
+	.load_encrypt_keys	= krb5enc_load_encrypt_keys,
+	.derive_checksum_key	= rfc3961_derive_checksum_key,
+	.load_checksum_key	= rfc3961_load_checksum_key,
 };

[RFC PATCH 12/24] crypto/krb5: Implement the Kerberos5 rfc3961 encrypt and decrypt functions

[David Howells]

Add functions that encrypt and decrypt a message according to rfc3961 sec
5.3, using Ki to checksum the data to be secured and Ke to encrypt it
during the encryption phase, then decrypting with Ke and verifying the
checksum with Ki in the decryption phase.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/krb5/internal.h           |  13 +++
 crypto/krb5/rfc3961_simplified.c | 146 +++++++++++++++++++++++++++++++
 2 files changed, 159 insertions(+)

diff --git a/crypto/krb5/internal.h b/crypto/krb5/internal.h
index 8418c23d5018..4533fb342953 100644
--- a/crypto/krb5/internal.h
+++ b/crypto/krb5/internal.h
@@ -7,6 +7,8 @@
 
 #include <linux/scatterlist.h>
 #include <crypto/krb5.h>
+#include <crypto/hash.h>
+#include <crypto/skcipher.h>
 
 /*
  * Profile used for key derivation and encryption.
@@ -137,6 +139,8 @@ int krb5_derive_Ki(const struct krb5_enctype *krb5, const struct krb5_buffer *TK
  */
 extern const struct krb5_crypto_profile rfc3961_simplified_profile;
 
+int crypto_shash_update_sg(struct shash_desc *desc, struct scatterlist *sg,
+			   size_t offset, size_t len);
 int krb5enc_derive_encrypt_keys(const struct krb5_enctype *krb5,
 				const struct krb5_buffer *TK,
 				unsigned int usage,
@@ -156,3 +160,12 @@ int rfc3961_load_checksum_key(const struct krb5_enctype *krb5,
 			      const struct krb5_buffer *Kc,
 			      struct krb5_buffer *setkey,
 			      gfp_t gfp);
+ssize_t krb5_aead_encrypt(const struct krb5_enctype *krb5,
+			  struct crypto_aead *aead,
+			  struct scatterlist *sg, unsigned int nr_sg, size_t sg_len,
+			  size_t data_offset, size_t data_len,
+			  bool preconfounded);
+int krb5_aead_decrypt(const struct krb5_enctype *krb5,
+		      struct crypto_aead *aead,
+		      struct scatterlist *sg, unsigned int nr_sg,
+		      size_t *_offset, size_t *_len);
diff --git a/crypto/krb5/rfc3961_simplified.c b/crypto/krb5/rfc3961_simplified.c
index d25fbd574dde..55f295f3ac5f 100644
--- a/crypto/krb5/rfc3961_simplified.c
+++ b/crypto/krb5/rfc3961_simplified.c
@@ -66,7 +66,10 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
+#include <linux/random.h>
+#include <linux/skbuff.h>
 #include <linux/slab.h>
+#include <linux/highmem.h>
 #include <linux/lcm.h>
 #include <crypto/skcipher.h>
 #include <crypto/hash.h>
@@ -75,6 +78,31 @@
 /* Maximum blocksize for the supported crypto algorithms */
 #define KRB5_MAX_BLOCKSIZE  (16)
 
+int crypto_shash_update_sg(struct shash_desc *desc, struct scatterlist *sg,
+			   size_t offset, size_t len)
+{
+	do {
+		int ret;
+
+		if (offset < sg->length) {
+			struct page *page = sg_page(sg);
+			void *p = kmap_local_page(page);
+			void *q = p + sg->offset + offset;
+			size_t seg = min_t(size_t, len, sg->length - offset);
+
+			ret = crypto_shash_update(desc, q, seg);
+			kunmap_local(p);
+			if (ret < 0)
+				return ret;
+			len -= seg;
+			offset = 0;
+		} else {
+			offset -= sg->length;
+		}
+	} while (len > 0 && (sg = sg_next(sg)));
+	return 0;
+}
+
 static int rfc3961_do_encrypt(struct crypto_sync_skcipher *tfm, void *iv,
 			      const struct krb5_buffer *in, struct krb5_buffer *out)
 {
@@ -503,6 +531,122 @@ int rfc3961_load_checksum_key(const struct krb5_enctype *krb5,
 		return -ENOMEM;
 	return 0;
 }
+
+/*
+ * Apply encryption and checksumming functions to part of a scatterlist.
+ */
+ssize_t krb5_aead_encrypt(const struct krb5_enctype *krb5,
+			  struct crypto_aead *aead,
+			  struct scatterlist *sg, unsigned int nr_sg, size_t sg_len,
+			  size_t data_offset, size_t data_len,
+			  bool preconfounded)
+{
+	struct aead_request *req;
+	ssize_t ret, done;
+	size_t bsize, base_len, secure_offset, secure_len, pad_len, cksum_offset;
+	void *buffer;
+	u8 *iv;
+
+	if (WARN_ON(data_offset != krb5->conf_len))
+		return -EINVAL; /* Data is in wrong place */
+
+	secure_offset	= 0;
+	base_len	= krb5->conf_len + data_len;
+	pad_len		= 0;
+	secure_len	= base_len + pad_len;
+	cksum_offset	= secure_len;
+	if (WARN_ON(cksum_offset + krb5->cksum_len > sg_len))
+		return -EFAULT;
+
+	bsize = krb5_aead_size(aead) +
+		krb5_aead_ivsize(aead);
+	buffer = kzalloc(bsize, GFP_NOFS);
+	if (!buffer)
+		return -ENOMEM;
+
+	/* Insert the confounder into the buffer */
+	ret = -EFAULT;
+	if (!preconfounded) {
+		get_random_bytes(buffer, krb5->conf_len);
+		done = sg_pcopy_from_buffer(sg, nr_sg, buffer, krb5->conf_len,
+					    secure_offset);
+		if (done != krb5->conf_len)
+			goto error;
+	}
+
+	/* We may need to pad out to the crypto blocksize. */
+	if (pad_len) {
+		done = sg_zero_buffer(sg, nr_sg, pad_len, data_offset + data_len);
+		if (done != pad_len)
+			goto error;
+	}
+
+	/* Hash and encrypt the message. */
+	req = buffer;
+	iv = buffer + krb5_aead_size(aead);
+
+	aead_request_set_tfm(req, aead);
+	aead_request_set_callback(req, 0, NULL, NULL);
+	aead_request_set_crypt(req, sg, sg, secure_len, iv);
+	ret = crypto_aead_encrypt(req);
+	if (ret < 0)
+		goto error;
+
+	ret = secure_len + krb5->cksum_len;
+
+error:
+	kfree_sensitive(buffer);
+	return ret;
+}
+
+/*
+ * Apply decryption and checksumming functions to a message.  The offset and
+ * length are updated to reflect the actual content of the encrypted region.
+ */
+int krb5_aead_decrypt(const struct krb5_enctype *krb5,
+		      struct crypto_aead *aead,
+		      struct scatterlist *sg, unsigned int nr_sg,
+		      size_t *_offset, size_t *_len)
+{
+	struct aead_request *req;
+	size_t bsize;
+	void *buffer;
+	int ret;
+	u8 *iv;
+
+	if (WARN_ON(*_offset != 0))
+		return -EINVAL; /* Can't set offset on aead */
+
+	if (*_len < krb5->conf_len + krb5->cksum_len)
+		return -EPROTO;
+
+	bsize = krb5_aead_size(aead) +
+		krb5_aead_ivsize(aead);
+	buffer = kzalloc(bsize, GFP_NOFS);
+	if (!buffer)
+		return -ENOMEM;
+
+	/* Decrypt the message and verify its checksum. */
+	req = buffer;
+	iv = buffer + krb5_aead_size(aead);
+
+	aead_request_set_tfm(req, aead);
+	aead_request_set_callback(req, 0, NULL, NULL);
+	aead_request_set_crypt(req, sg, sg, *_len, iv);
+	ret = crypto_aead_decrypt(req);
+	if (ret < 0)
+		goto error;
+
+	/* Adjust the boundaries of the data. */
+	*_offset += krb5->conf_len;
+	*_len -= krb5->conf_len + krb5->cksum_len;
+	ret = 0;
+
+error:
+	kfree_sensitive(buffer);
+	return ret;
+}
+
 const struct krb5_crypto_profile rfc3961_simplified_profile = {
 	.calc_PRF		= rfc3961_calc_PRF,
 	.calc_Kc		= rfc3961_calc_DK,
@@ -512,4 +656,6 @@ const struct krb5_crypto_profile rfc3961_simplified_profile = {
 	.load_encrypt_keys	= krb5enc_load_encrypt_keys,
 	.derive_checksum_key	= rfc3961_derive_checksum_key,
 	.load_checksum_key	= rfc3961_load_checksum_key,
+	.encrypt		= krb5_aead_encrypt,
+	.decrypt		= krb5_aead_decrypt,
 };

[RFC PATCH 13/24] crypto/krb5: Implement the Kerberos5 rfc3961 get_mic and verify_mic

[David Howells]

Add functions that sign and verify a message according to rfc3961 sec 5.4,
using Kc to generate a checksum and insert it into the MIC field in the
skbuff in the sign phase then checksum the data and compare it to the MIC
in the verify phase.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/krb5/internal.h           |  10 +++
 crypto/krb5/rfc3961_simplified.c | 130 +++++++++++++++++++++++++++++++
 2 files changed, 140 insertions(+)

diff --git a/crypto/krb5/internal.h b/crypto/krb5/internal.h
index 4533fb342953..eaaa9c13c8b3 100644
--- a/crypto/krb5/internal.h
+++ b/crypto/krb5/internal.h
@@ -169,3 +169,13 @@ int krb5_aead_decrypt(const struct krb5_enctype *krb5,
 		      struct crypto_aead *aead,
 		      struct scatterlist *sg, unsigned int nr_sg,
 		      size_t *_offset, size_t *_len);
+ssize_t rfc3961_get_mic(const struct krb5_enctype *krb5,
+			struct crypto_shash *shash,
+			const struct krb5_buffer *metadata,
+			struct scatterlist *sg, unsigned int nr_sg, size_t sg_len,
+			size_t data_offset, size_t data_len);
+int rfc3961_verify_mic(const struct krb5_enctype *krb5,
+		       struct crypto_shash *shash,
+		       const struct krb5_buffer *metadata,
+		       struct scatterlist *sg, unsigned int nr_sg,
+		       size_t *_offset, size_t *_len);
diff --git a/crypto/krb5/rfc3961_simplified.c b/crypto/krb5/rfc3961_simplified.c
index 55f295f3ac5f..59f0e7c823f7 100644
--- a/crypto/krb5/rfc3961_simplified.c
+++ b/crypto/krb5/rfc3961_simplified.c
@@ -647,6 +647,134 @@ int krb5_aead_decrypt(const struct krb5_enctype *krb5,
 	return ret;
 }
 
+/*
+ * Generate a checksum over some metadata and part of an skbuff and insert the
+ * MIC into the skbuff immediately prior to the data.
+ */
+ssize_t rfc3961_get_mic(const struct krb5_enctype *krb5,
+			struct crypto_shash *shash,
+			const struct krb5_buffer *metadata,
+			struct scatterlist *sg, unsigned int nr_sg, size_t sg_len,
+			size_t data_offset, size_t data_len)
+{
+	struct shash_desc *desc;
+	ssize_t ret, done;
+	size_t bsize;
+	void *buffer, *digest;
+
+	if (WARN_ON(data_offset != krb5->cksum_len))
+		return -EMSGSIZE;
+
+	bsize = krb5_shash_size(shash) +
+		krb5_digest_size(shash);
+	buffer = kzalloc(bsize, GFP_NOFS);
+	if (!buffer)
+		return -ENOMEM;
+
+	/* Calculate the MIC with key Kc and store it into the skb */
+	desc = buffer;
+	desc->tfm = shash;
+	ret = crypto_shash_init(desc);
+	if (ret < 0)
+		goto error;
+
+	if (metadata) {
+		ret = crypto_shash_update(desc, metadata->data, metadata->len);
+		if (ret < 0)
+			goto error;
+	}
+
+	ret = crypto_shash_update_sg(desc, sg, data_offset, data_len);
+	if (ret < 0)
+		goto error;
+
+	digest = buffer + krb5_shash_size(shash);
+	ret = crypto_shash_final(desc, digest);
+	if (ret < 0)
+		goto error;
+
+	ret = -EFAULT;
+	done = sg_pcopy_from_buffer(sg, nr_sg, digest, krb5->cksum_len,
+				    data_offset - krb5->cksum_len);
+	if (done != krb5->cksum_len)
+		goto error;
+
+	ret = krb5->cksum_len + data_len;
+
+error:
+	kfree_sensitive(buffer);
+	return ret;
+}
+
+/*
+ * Check the MIC on a region of an skbuff.  The offset and length are updated
+ * to reflect the actual content of the secure region.
+ */
+int rfc3961_verify_mic(const struct krb5_enctype *krb5,
+		       struct crypto_shash *shash,
+		       const struct krb5_buffer *metadata,
+		       struct scatterlist *sg, unsigned int nr_sg,
+		       size_t *_offset, size_t *_len)
+{
+	struct shash_desc *desc;
+	ssize_t done;
+	size_t bsize, data_offset, data_len, offset = *_offset, len = *_len;
+	void *buffer = NULL;
+	int ret;
+	u8 *cksum, *cksum2;
+
+	if (len < krb5->cksum_len)
+		return -EPROTO;
+	data_offset = offset + krb5->cksum_len;
+	data_len = len - krb5->cksum_len;
+
+	bsize = krb5_shash_size(shash) +
+		krb5_digest_size(shash) * 2;
+	buffer = kzalloc(bsize, GFP_NOFS);
+	if (!buffer)
+		return -ENOMEM;
+
+	cksum = buffer +
+		krb5_shash_size(shash);
+	cksum2 = buffer +
+		krb5_shash_size(shash) +
+		krb5_digest_size(shash);
+
+	/* Calculate the MIC */
+	desc = buffer;
+	desc->tfm = shash;
+	ret = crypto_shash_init(desc);
+	if (ret < 0)
+		goto error;
+
+	if (metadata) {
+		ret = crypto_shash_update(desc, metadata->data, metadata->len);
+		if (ret < 0)
+			goto error;
+	}
+
+	crypto_shash_update_sg(desc, sg, data_offset, data_len);
+	crypto_shash_final(desc, cksum);
+
+	ret = -EFAULT;
+	done = sg_pcopy_to_buffer(sg, nr_sg, cksum2, krb5->cksum_len, offset);
+	if (done != krb5->cksum_len)
+		goto error;
+
+	if (memcmp(cksum, cksum2, krb5->cksum_len) != 0) {
+		ret = -EBADMSG;
+		goto error;
+	}
+
+	*_offset += krb5->cksum_len;
+	*_len -= krb5->cksum_len;
+	ret = 0;
+
+error:
+	kfree_sensitive(buffer);
+	return ret;
+}
+
 const struct krb5_crypto_profile rfc3961_simplified_profile = {
 	.calc_PRF		= rfc3961_calc_PRF,
 	.calc_Kc		= rfc3961_calc_DK,
@@ -658,4 +786,6 @@ const struct krb5_crypto_profile rfc3961_simplified_profile = {
 	.load_checksum_key	= rfc3961_load_checksum_key,
 	.encrypt		= krb5_aead_encrypt,
 	.decrypt		= krb5_aead_decrypt,
+	.get_mic		= rfc3961_get_mic,
+	.verify_mic		= rfc3961_verify_mic,
 };

[RFC PATCH 14/24] crypto/krb5: Implement the AES enctypes from rfc3962

[David Howells]

Implement the aes128-cts-hmac-sha1-96 and aes256-cts-hmac-sha1-96 enctypes
from rfc3962, using the rfc3961 kerberos 5 simplified crypto scheme.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/krb5/Kconfig       |   1 +
 crypto/krb5/Makefile      |   3 +-
 crypto/krb5/internal.h    |   6 ++
 crypto/krb5/krb5_api.c    |   2 +
 crypto/krb5/rfc3962_aes.c | 115 ++++++++++++++++++++++++++++++++++++++
 5 files changed, 126 insertions(+), 1 deletion(-)
 create mode 100644 crypto/krb5/rfc3962_aes.c

diff --git a/crypto/krb5/Kconfig b/crypto/krb5/Kconfig
index 079873618abf..2ad874990dc8 100644
--- a/crypto/krb5/Kconfig
+++ b/crypto/krb5/Kconfig
@@ -5,6 +5,7 @@ config CRYPTO_KRB5
 	select CRYPTO_AUTHENC
 	select CRYPTO_SKCIPHER
 	select CRYPTO_HASH_INFO
+	select CRYPTO_HMAC
 	select CRYPTO_SHA1
 	select CRYPTO_CBC
 	select CRYPTO_CTS
diff --git a/crypto/krb5/Makefile b/crypto/krb5/Makefile
index 8dad8e3bf086..35f21411abf8 100644
--- a/crypto/krb5/Makefile
+++ b/crypto/krb5/Makefile
@@ -6,6 +6,7 @@
 krb5-y += \
 	krb5_kdf.o \
 	krb5_api.o \
-	rfc3961_simplified.o
+	rfc3961_simplified.o \
+	rfc3962_aes.o
 
 obj-$(CONFIG_CRYPTO_KRB5) += krb5.o
diff --git a/crypto/krb5/internal.h b/crypto/krb5/internal.h
index eaaa9c13c8b3..267ca978bda5 100644
--- a/crypto/krb5/internal.h
+++ b/crypto/krb5/internal.h
@@ -179,3 +179,9 @@ int rfc3961_verify_mic(const struct krb5_enctype *krb5,
 		       const struct krb5_buffer *metadata,
 		       struct scatterlist *sg, unsigned int nr_sg,
 		       size_t *_offset, size_t *_len);
+
+/*
+ * rfc3962_aes.c
+ */
+extern const struct krb5_enctype krb5_aes128_cts_hmac_sha1_96;
+extern const struct krb5_enctype krb5_aes256_cts_hmac_sha1_96;
diff --git a/crypto/krb5/krb5_api.c b/crypto/krb5/krb5_api.c
index 8fc3a1b9d4ad..ecc6655953d5 100644
--- a/crypto/krb5/krb5_api.c
+++ b/crypto/krb5/krb5_api.c
@@ -17,6 +17,8 @@ MODULE_AUTHOR("Red Hat, Inc.");
 MODULE_LICENSE("GPL");
 
 static const struct krb5_enctype *const krb5_supported_enctypes[] = {
+	&krb5_aes128_cts_hmac_sha1_96,
+	&krb5_aes256_cts_hmac_sha1_96,
 };
 
 /**
diff --git a/crypto/krb5/rfc3962_aes.c b/crypto/krb5/rfc3962_aes.c
new file mode 100644
index 000000000000..5cbf8f4638b9
--- /dev/null
+++ b/crypto/krb5/rfc3962_aes.c
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: BSD-3-Clause
+/* rfc3962 Advanced Encryption Standard (AES) Encryption for Kerberos 5
+ *
+ * Parts borrowed from net/sunrpc/auth_gss/.
+ */
+/*
+ * COPYRIGHT (c) 2008
+ * The Regents of the University of Michigan
+ * ALL RIGHTS RESERVED
+ *
+ * Permission is granted to use, copy, create derivative works
+ * and redistribute this software and such derivative works
+ * for any purpose, so long as the name of The University of
+ * Michigan is not used in any advertising or publicity
+ * pertaining to the use of distribution of this software
+ * without specific, written prior authorization.  If the
+ * above copyright notice or any other identification of the
+ * University of Michigan is included in any copy of any
+ * portion of this software, then the disclaimer below must
+ * also be included.
+ *
+ * THIS SOFTWARE IS PROVIDED AS IS, WITHOUT REPRESENTATION
+ * FROM THE UNIVERSITY OF MICHIGAN AS TO ITS FITNESS FOR ANY
+ * PURPOSE, AND WITHOUT WARRANTY BY THE UNIVERSITY OF
+ * MICHIGAN OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING
+ * WITHOUT LIMITATION THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
+ * REGENTS OF THE UNIVERSITY OF MICHIGAN SHALL NOT BE LIABLE
+ * FOR ANY DAMAGES, INCLUDING SPECIAL, INDIRECT, INCIDENTAL, OR
+ * CONSEQUENTIAL DAMAGES, WITH RESPECT TO ANY CLAIM ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OF THE SOFTWARE, EVEN
+ * IF IT HAS BEEN OR IS HEREAFTER ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGES.
+ */
+
+/*
+ * Copyright (C) 1998 by the FundsXpress, INC.
+ *
+ * All rights reserved.
+ *
+ * Export of this software from the United States of America may require
+ * a specific license from the United States Government.  It is the
+ * responsibility of any person or organization contemplating export to
+ * obtain such a license before exporting.
+ *
+ * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
+ * distribute this software and its documentation for any purpose and
+ * without fee is hereby granted, provided that the above copyright
+ * notice appear in all copies and that both that copyright notice and
+ * this permission notice appear in supporting documentation, and that
+ * the name of FundsXpress. not be used in advertising or publicity pertaining
+ * to distribution of the software without specific, written prior
+ * permission.  FundsXpress makes no representations about the suitability of
+ * this software for any purpose.  It is provided "as is" without express
+ * or implied warranty.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+/*
+ * Copyright (C) 2025 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include "internal.h"
+
+const struct krb5_enctype krb5_aes128_cts_hmac_sha1_96 = {
+	.etype		= KRB5_ENCTYPE_AES128_CTS_HMAC_SHA1_96,
+	.ctype		= KRB5_CKSUMTYPE_HMAC_SHA1_96_AES128,
+	.name		= "aes128-cts-hmac-sha1-96",
+	.encrypt_name	= "krb5enc(hmac(sha1),cts(cbc(aes)))",
+	.cksum_name	= "hmac(sha1)",
+	.hash_name	= "sha1",
+	.derivation_enc	= "cts(cbc(aes))",
+	.key_bytes	= 16,
+	.key_len	= 16,
+	.Kc_len		= 16,
+	.Ke_len		= 16,
+	.Ki_len		= 16,
+	.block_len	= 16,
+	.conf_len	= 16,
+	.cksum_len	= 12,
+	.hash_len	= 20,
+	.prf_len	= 16,
+	.keyed_cksum	= true,
+	.random_to_key	= NULL, /* Identity */
+	.profile	= &rfc3961_simplified_profile,
+};
+
+const struct krb5_enctype krb5_aes256_cts_hmac_sha1_96 = {
+	.etype		= KRB5_ENCTYPE_AES256_CTS_HMAC_SHA1_96,
+	.ctype		= KRB5_CKSUMTYPE_HMAC_SHA1_96_AES256,
+	.name		= "aes256-cts-hmac-sha1-96",
+	.encrypt_name	= "krb5enc(hmac(sha1),cts(cbc(aes)))",
+	.cksum_name	= "hmac(sha1)",
+	.hash_name	= "sha1",
+	.derivation_enc	= "cts(cbc(aes))",
+	.key_bytes	= 32,
+	.key_len	= 32,
+	.Kc_len		= 32,
+	.Ke_len		= 32,
+	.Ki_len		= 32,
+	.block_len	= 16,
+	.conf_len	= 16,
+	.cksum_len	= 12,
+	.hash_len	= 20,
+	.prf_len	= 16,
+	.keyed_cksum	= true,
+	.random_to_key	= NULL, /* Identity */
+	.profile	= &rfc3961_simplified_profile,
+};

[RFC PATCH 15/24] crypto/krb5: Implement the AES enctypes from rfc8009

[David Howells]

Implement the aes128-cts-hmac-sha256-128 and aes256-cts-hmac-sha384-192
enctypes from rfc8009, overriding the rfc3961 kerberos 5 simplified crypto
scheme.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/krb5/Kconfig        |   2 +
 crypto/krb5/Makefile       |   3 +-
 crypto/krb5/internal.h     |  16 ++
 crypto/krb5/krb5_api.c     |   2 +
 crypto/krb5/rfc8009_aes2.c | 296 +++++++++++++++++++++++++++++++++++++
 include/crypto/krb5.h      |   4 +
 6 files changed, 322 insertions(+), 1 deletion(-)
 create mode 100644 crypto/krb5/rfc8009_aes2.c

diff --git a/crypto/krb5/Kconfig b/crypto/krb5/Kconfig
index 2ad874990dc8..52f0ed2d7820 100644
--- a/crypto/krb5/Kconfig
+++ b/crypto/krb5/Kconfig
@@ -7,6 +7,8 @@ config CRYPTO_KRB5
 	select CRYPTO_HASH_INFO
 	select CRYPTO_HMAC
 	select CRYPTO_SHA1
+	select CRYPTO_SHA256
+	select CRYPTO_SHA512
 	select CRYPTO_CBC
 	select CRYPTO_CTS
 	select CRYPTO_AES
diff --git a/crypto/krb5/Makefile b/crypto/krb5/Makefile
index 35f21411abf8..7fd215ec3a85 100644
--- a/crypto/krb5/Makefile
+++ b/crypto/krb5/Makefile
@@ -7,6 +7,7 @@ krb5-y += \
 	krb5_kdf.o \
 	krb5_api.o \
 	rfc3961_simplified.o \
-	rfc3962_aes.o
+	rfc3962_aes.o \
+	rfc8009_aes2.o
 
 obj-$(CONFIG_CRYPTO_KRB5) += krb5.o
diff --git a/crypto/krb5/internal.h b/crypto/krb5/internal.h
index 267ca978bda5..81bf38cf12fc 100644
--- a/crypto/krb5/internal.h
+++ b/crypto/krb5/internal.h
@@ -185,3 +185,19 @@ int rfc3961_verify_mic(const struct krb5_enctype *krb5,
  */
 extern const struct krb5_enctype krb5_aes128_cts_hmac_sha1_96;
 extern const struct krb5_enctype krb5_aes256_cts_hmac_sha1_96;
+
+/*
+ * rfc8009_aes2.c
+ */
+extern const struct krb5_enctype krb5_aes128_cts_hmac_sha256_128;
+extern const struct krb5_enctype krb5_aes256_cts_hmac_sha384_192;
+int authenc_derive_encrypt_keys(const struct krb5_enctype *krb5,
+				const struct krb5_buffer *TK,
+				unsigned int usage,
+				struct krb5_buffer *setkey,
+				gfp_t gfp);
+int authenc_load_encrypt_keys(const struct krb5_enctype *krb5,
+			      const struct krb5_buffer *Ke,
+			      const struct krb5_buffer *Ki,
+			      struct krb5_buffer *setkey,
+			      gfp_t gfp);
diff --git a/crypto/krb5/krb5_api.c b/crypto/krb5/krb5_api.c
index ecc6655953d5..5b94cc5db461 100644
--- a/crypto/krb5/krb5_api.c
+++ b/crypto/krb5/krb5_api.c
@@ -19,6 +19,8 @@ MODULE_LICENSE("GPL");
 static const struct krb5_enctype *const krb5_supported_enctypes[] = {
 	&krb5_aes128_cts_hmac_sha1_96,
 	&krb5_aes256_cts_hmac_sha1_96,
+	&krb5_aes128_cts_hmac_sha256_128,
+	&krb5_aes256_cts_hmac_sha384_192,
 };
 
 /**
diff --git a/crypto/krb5/rfc8009_aes2.c b/crypto/krb5/rfc8009_aes2.c
new file mode 100644
index 000000000000..d7225187ce8b
--- /dev/null
+++ b/crypto/krb5/rfc8009_aes2.c
@@ -0,0 +1,296 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* rfc8009 AES Encryption with HMAC-SHA2 for Kerberos 5
+ *
+ * Copyright (C) 2025 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/slab.h>
+#include <linux/rtnetlink.h>
+#include <crypto/authenc.h>
+#include "internal.h"
+
+static const struct krb5_buffer rfc8009_no_context = { .len = 0, .data = "" };
+
+/*
+ * Calculate the key derivation function KDF-HMAC-SHA2(key, label, [context,] k)
+ *
+ *	KDF-HMAC-SHA2(key, label, [context,] k) = k-truncate(K1)
+ *
+ *	Using the appropriate one of:
+ *		K1 = HMAC-SHA-256(key, 0x00000001 | label | 0x00 | k)
+ *		K1 = HMAC-SHA-384(key, 0x00000001 | label | 0x00 | k)
+ *		K1 = HMAC-SHA-256(key, 0x00000001 | label | 0x00 | context | k)
+ *		K1 = HMAC-SHA-384(key, 0x00000001 | label | 0x00 | context | k)
+ *	[rfc8009 sec 3]
+ */
+static int rfc8009_calc_KDF_HMAC_SHA2(const struct krb5_enctype *krb5,
+				      const struct krb5_buffer *key,
+				      const struct krb5_buffer *label,
+				      const struct krb5_buffer *context,
+				      unsigned int k,
+				      struct krb5_buffer *result,
+				      gfp_t gfp)
+{
+	struct crypto_shash *shash;
+	struct krb5_buffer K1, data;
+	struct shash_desc *desc;
+	__be32 tmp;
+	size_t bsize;
+	void *buffer;
+	u8 *p;
+	int ret = -ENOMEM;
+
+	if (WARN_ON(result->len != k / 8))
+		return -EINVAL;
+
+	shash = crypto_alloc_shash(krb5->cksum_name, 0, 0);
+	if (IS_ERR(shash))
+		return (PTR_ERR(shash) == -ENOENT) ? -ENOPKG : PTR_ERR(shash);
+	ret = crypto_shash_setkey(shash, key->data, key->len);
+	if (ret < 0)
+		goto error_shash;
+
+	ret = -EINVAL;
+	if (WARN_ON(crypto_shash_digestsize(shash) * 8 < k))
+		goto error_shash;
+
+	ret = -ENOMEM;
+	data.len = 4 + label->len + 1 + context->len + 4;
+	bsize = krb5_shash_size(shash) +
+		krb5_digest_size(shash) +
+		crypto_roundup(data.len);
+	buffer = kzalloc(bsize, GFP_NOFS);
+	if (!buffer)
+		goto error_shash;
+
+	desc = buffer;
+	desc->tfm = shash;
+	ret = crypto_shash_init(desc);
+	if (ret < 0)
+		goto error;
+
+	p = data.data = buffer +
+		krb5_shash_size(shash) +
+		krb5_digest_size(shash);
+	*(__be32 *)p = htonl(0x00000001);
+	p += 4;
+	memcpy(p, label->data, label->len);
+	p += label->len;
+	*p++ = 0;
+	memcpy(p, context->data, context->len);
+	p += context->len;
+	tmp = htonl(k);
+	memcpy(p, &tmp, 4);
+	p += 4;
+
+	ret = -EINVAL;
+	if (WARN_ON(p - (u8 *)data.data != data.len))
+		goto error;
+
+	K1.len = crypto_shash_digestsize(shash);
+	K1.data = buffer +
+		krb5_shash_size(shash);
+
+	ret = crypto_shash_finup(desc, data.data, data.len, K1.data);
+	if (ret < 0)
+		goto error;
+
+	memcpy(result->data, K1.data, result->len);
+
+error:
+	kfree_sensitive(buffer);
+error_shash:
+	crypto_free_shash(shash);
+	return ret;
+}
+
+/*
+ * Calculate the pseudo-random function, PRF().
+ *
+ *	PRF = KDF-HMAC-SHA2(input-key, "prf", octet-string, 256)
+ *	PRF = KDF-HMAC-SHA2(input-key, "prf", octet-string, 384)
+ *
+ *      The "prfconstant" used in the PRF operation is the three-octet string
+ *      "prf".
+ *      [rfc8009 sec 5]
+ */
+static int rfc8009_calc_PRF(const struct krb5_enctype *krb5,
+			    const struct krb5_buffer *input_key,
+			    const struct krb5_buffer *octet_string,
+			    struct krb5_buffer *result,
+			    gfp_t gfp)
+{
+	static const struct krb5_buffer prfconstant = { 3, "prf" };
+
+	return rfc8009_calc_KDF_HMAC_SHA2(krb5, input_key, &prfconstant,
+					  octet_string, krb5->prf_len * 8,
+					  result, gfp);
+}
+
+/*
+ * Derive Ke.
+ *	Ke = KDF-HMAC-SHA2(base-key, usage | 0xAA, 128)
+ *	Ke = KDF-HMAC-SHA2(base-key, usage | 0xAA, 256)
+ *      [rfc8009 sec 5]
+ */
+static int rfc8009_calc_Ke(const struct krb5_enctype *krb5,
+			   const struct krb5_buffer *base_key,
+			   const struct krb5_buffer *usage_constant,
+			   struct krb5_buffer *result,
+			   gfp_t gfp)
+{
+	return rfc8009_calc_KDF_HMAC_SHA2(krb5, base_key, usage_constant,
+					  &rfc8009_no_context, krb5->key_bytes * 8,
+					  result, gfp);
+}
+
+/*
+ * Derive Kc/Ki
+ *	Kc = KDF-HMAC-SHA2(base-key, usage | 0x99, 128)
+ *	Ki = KDF-HMAC-SHA2(base-key, usage | 0x55, 128)
+ *	Kc = KDF-HMAC-SHA2(base-key, usage | 0x99, 192)
+ *	Ki = KDF-HMAC-SHA2(base-key, usage | 0x55, 192)
+ *      [rfc8009 sec 5]
+ */
+static int rfc8009_calc_Ki(const struct krb5_enctype *krb5,
+			   const struct krb5_buffer *base_key,
+			   const struct krb5_buffer *usage_constant,
+			   struct krb5_buffer *result,
+			   gfp_t gfp)
+{
+	return rfc8009_calc_KDF_HMAC_SHA2(krb5, base_key, usage_constant,
+					  &rfc8009_no_context, krb5->cksum_len * 8,
+					  result, gfp);
+}
+
+/*
+ * Derive the Ke and Ki keys and package them into a key parameter that can be
+ * given to the setkey of a authenc AEAD crypto object.
+ */
+int authenc_derive_encrypt_keys(const struct krb5_enctype *krb5,
+				const struct krb5_buffer *TK,
+				unsigned int usage,
+				struct krb5_buffer *setkey,
+				gfp_t gfp)
+{
+	struct krb5_buffer Ke, Ki;
+	__be32 *khdr = NULL;
+	int ret;
+
+	Ke.len  = krb5->Ke_len;
+	Ki.len  = krb5->Ki_len;
+	setkey->len = sizeof(__be32) * 3 + krb5->Ke_len + krb5->Ki_len;
+	setkey->data = kzalloc(setkey->len, GFP_KERNEL);
+	if (!setkey->data)
+		return -ENOMEM;
+
+	khdr = setkey->data;
+	Ke.data = setkey->data + 12;
+	Ki.data = setkey->data + 12 + Ke.len;
+
+	khdr[0] = htonl(1); /* Format 1 */
+	khdr[1] = htonl(Ke.len);
+	khdr[2] = htonl(Ki.len);
+
+	ret = krb5_derive_Ke(krb5, TK, usage, &Ke, gfp);
+	if (ret < 0) {
+		pr_err("get_Ke failed %d\n", ret);
+		return ret;
+	}
+	ret = krb5_derive_Ki(krb5, TK, usage, &Ki, gfp);
+	if (ret < 0)
+		pr_err("get_Ki failed %d\n", ret);
+	return ret;
+}
+
+/*
+ * Package predefined Ke and Ki keys and into a key parameter that can be given
+ * to the setkey of an authenc AEAD crypto object.
+ */
+int authenc_load_encrypt_keys(const struct krb5_enctype *krb5,
+			      const struct krb5_buffer *Ke,
+			      const struct krb5_buffer *Ki,
+			      struct krb5_buffer *setkey,
+			      gfp_t gfp)
+{
+	struct crypto_authenc_key_param *param;
+	struct rtattr *rta;
+
+	setkey->len = RTA_LENGTH(sizeof(*param)) + Ke->len + Ki->len;
+	setkey->data = kzalloc(setkey->len, GFP_KERNEL);
+	if (!setkey->data)
+		return -ENOMEM;
+
+	rta = setkey->data;
+	rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
+	rta->rta_len = RTA_LENGTH(sizeof(*param));
+	param = RTA_DATA(rta);
+	param->enckeylen = htonl(Ke->len);
+	memcpy((void *)(param + 1), Ki->data, Ki->len);
+	memcpy((void *)(param + 1) + Ki->len, Ke->data, Ke->len);
+	return 0;
+}
+
+static const struct krb5_crypto_profile rfc8009_crypto_profile = {
+	.calc_PRF		= rfc8009_calc_PRF,
+	.calc_Kc		= rfc8009_calc_Ki,
+	.calc_Ke		= rfc8009_calc_Ke,
+	.calc_Ki		= rfc8009_calc_Ki,
+	.derive_encrypt_keys	= authenc_derive_encrypt_keys,
+	.load_encrypt_keys	= authenc_load_encrypt_keys,
+	.derive_checksum_key	= rfc3961_derive_checksum_key,
+	.load_checksum_key	= rfc3961_load_checksum_key,
+	.encrypt		= NULL, //rfc8009_encrypt,
+	.decrypt		= NULL, //rfc8009_decrypt,
+	.get_mic		= rfc3961_get_mic,
+	.verify_mic		= rfc3961_verify_mic,
+};
+
+const struct krb5_enctype krb5_aes128_cts_hmac_sha256_128 = {
+	.etype		= KRB5_ENCTYPE_AES128_CTS_HMAC_SHA256_128,
+	.ctype		= KRB5_CKSUMTYPE_HMAC_SHA256_128_AES128,
+	.name		= "aes128-cts-hmac-sha256-128",
+	.encrypt_name	= "authenc(hmac(sha256),cts(cbc(aes)))",
+	.cksum_name	= "hmac(sha256)",
+	.hash_name	= "sha256",
+	.derivation_enc	= "cts(cbc(aes))",
+	.key_bytes	= 16,
+	.key_len	= 16,
+	.Kc_len		= 16,
+	.Ke_len		= 16,
+	.Ki_len		= 16,
+	.block_len	= 16,
+	.conf_len	= 16,
+	.cksum_len	= 16,
+	.hash_len	= 20,
+	.prf_len	= 32,
+	.keyed_cksum	= true,
+	.random_to_key	= NULL, /* Identity */
+	.profile	= &rfc8009_crypto_profile,
+};
+
+const struct krb5_enctype krb5_aes256_cts_hmac_sha384_192 = {
+	.etype		= KRB5_ENCTYPE_AES256_CTS_HMAC_SHA384_192,
+	.ctype		= KRB5_CKSUMTYPE_HMAC_SHA384_192_AES256,
+	.name		= "aes256-cts-hmac-sha384-192",
+	.encrypt_name	= "authenc(hmac(sha384),cts(cbc(aes)))",
+	.cksum_name	= "hmac(sha384)",
+	.hash_name	= "sha384",
+	.derivation_enc	= "cts(cbc(aes))",
+	.key_bytes	= 32,
+	.key_len	= 32,
+	.Kc_len		= 24,
+	.Ke_len		= 32,
+	.Ki_len		= 24,
+	.block_len	= 16,
+	.conf_len	= 16,
+	.cksum_len	= 24,
+	.hash_len	= 20,
+	.prf_len	= 48,
+	.keyed_cksum	= true,
+	.random_to_key	= NULL, /* Identity */
+	.profile	= &rfc8009_crypto_profile,
+};
diff --git a/include/crypto/krb5.h b/include/crypto/krb5.h
index a24d9ee53675..6921785688bf 100644
--- a/include/crypto/krb5.h
+++ b/include/crypto/krb5.h
@@ -31,6 +31,8 @@ struct scatterlist;
 #define KRB5_ENCTYPE_DES3_CBC_SHA1		0x0010
 #define KRB5_ENCTYPE_AES128_CTS_HMAC_SHA1_96	0x0011
 #define KRB5_ENCTYPE_AES256_CTS_HMAC_SHA1_96	0x0012
+#define KRB5_ENCTYPE_AES128_CTS_HMAC_SHA256_128	0x0013
+#define KRB5_ENCTYPE_AES256_CTS_HMAC_SHA384_192	0x0014
 #define KRB5_ENCTYPE_ARCFOUR_HMAC		0x0017
 #define KRB5_ENCTYPE_ARCFOUR_HMAC_EXP		0x0018
 #define KRB5_ENCTYPE_UNKNOWN			0x01ff
@@ -45,6 +47,8 @@ struct scatterlist;
 #define KRB5_CKSUMTYPE_HMAC_SHA1_DES3		0x000c
 #define KRB5_CKSUMTYPE_HMAC_SHA1_96_AES128	0x000f
 #define KRB5_CKSUMTYPE_HMAC_SHA1_96_AES256	0x0010
+#define KRB5_CKSUMTYPE_HMAC_SHA256_128_AES128	0x0013
+#define KRB5_CKSUMTYPE_HMAC_SHA384_192_AES256	0x0014
 #define KRB5_CKSUMTYPE_HMAC_MD5_ARCFOUR		-138 /* Microsoft md5 hmac cksumtype */
 
 /*

[RFC PATCH 16/24] crypto/krb5: Implement the AES encrypt/decrypt from rfc8009

[David Howells]

Implement encryption and decryption functions for AES + HMAC-SHA2 as
described in rfc8009 sec 5.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/krb5/rfc8009_aes2.c | 139 ++++++++++++++++++++++++++++++++++++-
 1 file changed, 137 insertions(+), 2 deletions(-)

diff --git a/crypto/krb5/rfc8009_aes2.c b/crypto/krb5/rfc8009_aes2.c
index d7225187ce8b..bcf84284abff 100644
--- a/crypto/krb5/rfc8009_aes2.c
+++ b/crypto/krb5/rfc8009_aes2.c
@@ -234,6 +234,141 @@ int authenc_load_encrypt_keys(const struct krb5_enctype *krb5,
 	return 0;
 }
 
+/*
+ * Apply encryption and checksumming functions to a message.  Unlike for
+ * RFC3961, for RFC8009, we have to chuck the starting IV into the hash first.
+ */
+static ssize_t rfc8009_encrypt(const struct krb5_enctype *krb5,
+			       struct crypto_aead *aead,
+			       struct scatterlist *sg, unsigned int nr_sg, size_t sg_len,
+			       size_t data_offset, size_t data_len,
+			       bool preconfounded)
+{
+	struct aead_request *req;
+	struct scatterlist bsg[2];
+	ssize_t ret, done;
+	size_t bsize, base_len, secure_offset, secure_len, pad_len, cksum_offset;
+	void *buffer;
+	u8 *iv, *ad;
+
+	if (WARN_ON(data_offset != krb5->conf_len))
+		return -EINVAL; /* Data is in wrong place */
+
+	secure_offset	= 0;
+	base_len	= krb5->conf_len + data_len;
+	pad_len		= 0;
+	secure_len	= base_len + pad_len;
+	cksum_offset	= secure_len;
+	if (WARN_ON(cksum_offset + krb5->cksum_len > sg_len))
+		return -EFAULT;
+
+	bsize = krb5_aead_size(aead) +
+		krb5_aead_ivsize(aead) * 2;
+	buffer = kzalloc(bsize, GFP_NOFS);
+	if (!buffer)
+		return -ENOMEM;
+
+	req = buffer;
+	iv = buffer + krb5_aead_size(aead);
+	ad = buffer + krb5_aead_size(aead) + krb5_aead_ivsize(aead);
+
+	/* Insert the confounder into the buffer */
+	ret = -EFAULT;
+	if (!preconfounded) {
+		get_random_bytes(buffer, krb5->conf_len);
+		done = sg_pcopy_from_buffer(sg, nr_sg, buffer, krb5->conf_len,
+					    secure_offset);
+		if (done != krb5->conf_len)
+			goto error;
+	}
+
+	/* We may need to pad out to the crypto blocksize. */
+	if (pad_len) {
+		done = sg_zero_buffer(sg, nr_sg, pad_len, data_offset + data_len);
+		if (done != pad_len)
+			goto error;
+	}
+
+	/* We need to include the starting IV in the hash. */
+	sg_init_table(bsg, 2);
+	sg_set_buf(&bsg[0], ad, krb5_aead_ivsize(aead));
+	sg_chain(bsg, 2, sg);
+
+	/* Hash and encrypt the message. */
+	aead_request_set_tfm(req, aead);
+	aead_request_set_callback(req, 0, NULL, NULL);
+	aead_request_set_ad(req, krb5_aead_ivsize(aead));
+	aead_request_set_crypt(req, bsg, bsg, secure_len, iv);
+	ret = crypto_aead_encrypt(req);
+	if (ret < 0)
+		goto error;
+
+	ret = secure_len + krb5->cksum_len;
+
+error:
+	kfree_sensitive(buffer);
+	return ret;
+}
+
+/*
+ * Apply decryption and checksumming functions to a message.  Unlike for
+ * RFC3961, for RFC8009, we have to chuck the starting IV into the hash first.
+ *
+ * The offset and length are updated to reflect the actual content of the
+ * encrypted region.
+ */
+static int rfc8009_decrypt(const struct krb5_enctype *krb5,
+			   struct crypto_aead *aead,
+			   struct scatterlist *sg, unsigned int nr_sg,
+			   size_t *_offset, size_t *_len)
+{
+	struct aead_request *req;
+	struct scatterlist bsg[2];
+	size_t bsize;
+	void *buffer;
+	int ret;
+	u8 *iv, *ad;
+
+	if (WARN_ON(*_offset != 0))
+		return -EINVAL; /* Can't set offset on aead */
+
+	if (*_len < krb5->conf_len + krb5->cksum_len)
+		return -EPROTO;
+
+	bsize = krb5_aead_size(aead) +
+		krb5_aead_ivsize(aead) * 2;
+	buffer = kzalloc(bsize, GFP_NOFS);
+	if (!buffer)
+		return -ENOMEM;
+
+	req = buffer;
+	iv = buffer + krb5_aead_size(aead);
+	ad = buffer + krb5_aead_size(aead) + krb5_aead_ivsize(aead);
+
+	/* We need to include the starting IV in the hash. */
+	sg_init_table(bsg, 2);
+	sg_set_buf(&bsg[0], ad, krb5_aead_ivsize(aead));
+	sg_chain(bsg, 2, sg);
+
+	/* Decrypt the message and verify its checksum. */
+	aead_request_set_tfm(req, aead);
+	aead_request_set_callback(req, 0, NULL, NULL);
+	aead_request_set_ad(req, krb5_aead_ivsize(aead));
+	aead_request_set_crypt(req, bsg, bsg, *_len, iv);
+	ret = crypto_aead_decrypt(req);
+	if (ret < 0)
+		goto error;
+
+	/* Adjust the boundaries of the data. */
+	*_offset += krb5->conf_len;
+	*_len -= krb5->conf_len + krb5->cksum_len;
+	ret = 0;
+
+error:
+	kfree_sensitive(buffer);
+	return ret;
+}
+
 static const struct krb5_crypto_profile rfc8009_crypto_profile = {
 	.calc_PRF		= rfc8009_calc_PRF,
 	.calc_Kc		= rfc8009_calc_Ki,
@@ -243,8 +378,8 @@ static const struct krb5_crypto_profile rfc8009_crypto_profile = {
 	.load_encrypt_keys	= authenc_load_encrypt_keys,
 	.derive_checksum_key	= rfc3961_derive_checksum_key,
 	.load_checksum_key	= rfc3961_load_checksum_key,
-	.encrypt		= NULL, //rfc8009_encrypt,
-	.decrypt		= NULL, //rfc8009_decrypt,
+	.encrypt		= rfc8009_encrypt,
+	.decrypt		= rfc8009_decrypt,
 	.get_mic		= rfc3961_get_mic,
 	.verify_mic		= rfc3961_verify_mic,
 };

[RFC PATCH 17/24] crypto/krb5: Implement crypto self-testing

[David Howells]

Implement self-testing infrastructure to test the pseudo-random function,
key derivation, encryption and checksumming.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/krb5/Kconfig         |   7 +
 crypto/krb5/Makefile        |   4 +
 crypto/krb5/internal.h      |  48 ++++
 crypto/krb5/krb5_api.c      |  11 +
 crypto/krb5/selftest.c      | 544 ++++++++++++++++++++++++++++++++++++
 crypto/krb5/selftest_data.c |  38 +++
 6 files changed, 652 insertions(+)
 create mode 100644 crypto/krb5/selftest.c
 create mode 100644 crypto/krb5/selftest_data.c

diff --git a/crypto/krb5/Kconfig b/crypto/krb5/Kconfig
index 52f0ed2d7820..82d7e3b55878 100644
--- a/crypto/krb5/Kconfig
+++ b/crypto/krb5/Kconfig
@@ -15,3 +15,10 @@ config CRYPTO_KRB5
 	help
 	  Provide a library for provision of Kerberos-5-based crypto.  This is
 	  intended for network filesystems to use.
+
+config CRYPTO_KRB5_SELFTESTS
+	bool "Kerberos 5 crypto selftests"
+	depends on CRYPTO_KRB5
+	help
+	  Turn on some self-testing for the kerberos 5 crypto functions.  These
+	  will be performed on module load or boot, if compiled in.
diff --git a/crypto/krb5/Makefile b/crypto/krb5/Makefile
index 7fd215ec3a85..1ad327227744 100644
--- a/crypto/krb5/Makefile
+++ b/crypto/krb5/Makefile
@@ -10,4 +10,8 @@ krb5-y += \
 	rfc3962_aes.o \
 	rfc8009_aes2.o
 
+krb5-$(CONFIG_CRYPTO_KRB5_SELFTESTS) += \
+	selftest.o \
+	selftest_data.o
+
 obj-$(CONFIG_CRYPTO_KRB5) += krb5.o
diff --git a/crypto/krb5/internal.h b/crypto/krb5/internal.h
index 81bf38cf12fc..a40f120b4954 100644
--- a/crypto/krb5/internal.h
+++ b/crypto/krb5/internal.h
@@ -114,6 +114,37 @@ struct krb5_crypto_profile {
 	crypto_roundup(crypto_shash_digestsize(TFM))
 #define round16(x) (((x) + 15) & ~15)
 
+/*
+ * Self-testing data.
+ */
+struct krb5_prf_test {
+	u32 etype;
+	const char *name, *key, *octet, *prf;
+};
+
+struct krb5_key_test_one {
+	u32 use;
+	const char *key;
+};
+
+struct krb5_key_test {
+	u32 etype;
+	const char *name, *key;
+	struct krb5_key_test_one Kc, Ke, Ki;
+};
+
+struct krb5_enc_test {
+	u32 etype;
+	u32 usage;
+	const char *name, *plain, *conf, *K0, *Ke, *Ki, *ct;
+};
+
+struct krb5_mic_test {
+	u32 etype;
+	u32 usage;
+	const char *name, *plain, *K0, *Kc, *mic;
+};
+
 /*
  * krb5_api.c
  */
@@ -201,3 +232,20 @@ int authenc_load_encrypt_keys(const struct krb5_enctype *krb5,
 			      const struct krb5_buffer *Ki,
 			      struct krb5_buffer *setkey,
 			      gfp_t gfp);
+
+/*
+ * selftest.c
+ */
+#ifdef CONFIG_CRYPTO_KRB5_SELFTESTS
+int krb5_selftest(void);
+#else
+static inline int krb5_selftest(void) { return 0; }
+#endif
+
+/*
+ * selftest_data.c
+ */
+extern const struct krb5_prf_test krb5_prf_tests[];
+extern const struct krb5_key_test krb5_key_tests[];
+extern const struct krb5_enc_test krb5_enc_tests[];
+extern const struct krb5_mic_test krb5_mic_tests[];
diff --git a/crypto/krb5/krb5_api.c b/crypto/krb5/krb5_api.c
index 5b94cc5db461..8c2949ac9c07 100644
--- a/crypto/krb5/krb5_api.c
+++ b/crypto/krb5/krb5_api.c
@@ -437,3 +437,14 @@ int crypto_krb5_verify_mic(const struct krb5_enctype *krb5,
 					 _offset, _len);
 }
 EXPORT_SYMBOL(crypto_krb5_verify_mic);
+
+static int __init crypto_krb5_init(void)
+{
+	return krb5_selftest();
+}
+module_init(crypto_krb5_init);
+
+static void __exit crypto_krb5_exit(void)
+{
+}
+module_exit(crypto_krb5_exit);
diff --git a/crypto/krb5/selftest.c b/crypto/krb5/selftest.c
new file mode 100644
index 000000000000..2a81a6315a0d
--- /dev/null
+++ b/crypto/krb5/selftest.c
@@ -0,0 +1,544 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Kerberos library self-testing
+ *
+ * Copyright (C) 2025 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/slab.h>
+#include <crypto/skcipher.h>
+#include <crypto/hash.h>
+#include "internal.h"
+
+#define VALID(X) \
+	({								\
+		bool __x = (X);						\
+		if (__x) {						\
+			pr_warn("!!! TESTINVAL %s:%u\n", __FILE__, __LINE__); \
+			ret = -EBADMSG;					\
+		}							\
+		__x;							\
+	})
+
+#define CHECK(X) \
+	({								\
+		bool __x = (X);						\
+		if (__x) {						\
+			pr_warn("!!! TESTFAIL %s:%u\n", __FILE__, __LINE__); \
+			ret = -EBADMSG;					\
+		}							\
+		__x;							\
+	})
+
+enum which_key {
+	TEST_KC, TEST_KE, TEST_KI,
+};
+
+#if 0
+static void dump_sg(struct scatterlist *sg, unsigned int limit)
+{
+	unsigned int index = 0, n = 0;
+
+	for (; sg && limit > 0; sg = sg_next(sg)) {
+		unsigned int off = sg->offset, len = umin(sg->length, limit);
+		const void *p = kmap_local_page(sg_page(sg));
+
+		limit -= len;
+		while (len > 0) {
+			unsigned int part = umin(len, 32);
+
+			pr_notice("[%x] %04x: %*phN\n", n, index, part, p + off);
+			index += part;
+			off += part;
+			len -= part;
+		}
+
+		kunmap_local(p);
+		n++;
+	}
+}
+#endif
+
+static int prep_buf(struct krb5_buffer *buf)
+{
+	buf->data = kmalloc(buf->len, GFP_KERNEL);
+	if (!buf->data)
+		return -ENOMEM;
+	return 0;
+}
+
+#define PREP_BUF(BUF, LEN)					\
+	do {							\
+		(BUF)->len = (LEN);				\
+		ret = prep_buf((BUF));				\
+		if (ret < 0)					\
+			goto out;				\
+	} while (0)
+
+static int load_buf(struct krb5_buffer *buf, const char *from)
+{
+	size_t len = strlen(from);
+	int ret;
+
+	if (len > 1 && from[0] == '\'') {
+		PREP_BUF(buf, len - 1);
+		memcpy(buf->data, from + 1, len - 1);
+		ret = 0;
+		goto out;
+	}
+
+	if (VALID(len & 1))
+		return -EINVAL;
+
+	PREP_BUF(buf, len / 2);
+	ret = hex2bin(buf->data, from, buf->len);
+	if (ret < 0) {
+		VALID(1);
+		goto out;
+	}
+out:
+	return ret;
+}
+
+#define LOAD_BUF(BUF, FROM) do { ret = load_buf(BUF, FROM); if (ret < 0) goto out; } while (0)
+
+static void clear_buf(struct krb5_buffer *buf)
+{
+	kfree(buf->data);
+	buf->len = 0;
+	buf->data = NULL;
+}
+
+/*
+ * Perform a pseudo-random function check.
+ */
+static int krb5_test_one_prf(const struct krb5_prf_test *test)
+{
+	const struct krb5_enctype *krb5 = crypto_krb5_find_enctype(test->etype);
+	struct krb5_buffer key = {}, octet = {}, result = {}, prf = {};
+	int ret;
+
+	if (!krb5)
+		return -EOPNOTSUPP;
+
+	pr_notice("Running %s %s\n", krb5->name, test->name);
+
+	LOAD_BUF(&key,   test->key);
+	LOAD_BUF(&octet, test->octet);
+	LOAD_BUF(&prf,   test->prf);
+	PREP_BUF(&result, krb5->prf_len);
+
+	if (VALID(result.len != prf.len)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = krb5->profile->calc_PRF(krb5, &key, &octet, &result, GFP_KERNEL);
+	if (ret < 0) {
+		CHECK(1);
+		pr_warn("PRF calculation failed %d\n", ret);
+		goto out;
+	}
+
+	if (memcmp(result.data, prf.data, result.len) != 0) {
+		CHECK(1);
+		ret = -EKEYREJECTED;
+		goto out;
+	}
+
+	ret = 0;
+
+out:
+	clear_buf(&result);
+	clear_buf(&octet);
+	clear_buf(&key);
+	return ret;
+}
+
+/*
+ * Perform a key derivation check.
+ */
+static int krb5_test_key(const struct krb5_enctype *krb5,
+			 const struct krb5_buffer *base_key,
+			 const struct krb5_key_test_one *test,
+			 enum which_key which)
+{
+	struct krb5_buffer key = {}, result = {};
+	int ret;
+
+	LOAD_BUF(&key,   test->key);
+	PREP_BUF(&result, key.len);
+
+	switch (which) {
+	case TEST_KC:
+		ret = krb5_derive_Kc(krb5, base_key, test->use, &result, GFP_KERNEL);
+		break;
+	case TEST_KE:
+		ret = krb5_derive_Ke(krb5, base_key, test->use, &result, GFP_KERNEL);
+		break;
+	case TEST_KI:
+		ret = krb5_derive_Ki(krb5, base_key, test->use, &result, GFP_KERNEL);
+		break;
+	default:
+		VALID(1);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (ret < 0) {
+		CHECK(1);
+		pr_warn("Key derivation failed %d\n", ret);
+		goto out;
+	}
+
+	if (memcmp(result.data, key.data, result.len) != 0) {
+		CHECK(1);
+		ret = -EKEYREJECTED;
+		goto out;
+	}
+
+out:
+	clear_buf(&key);
+	clear_buf(&result);
+	return ret;
+}
+
+static int krb5_test_one_key(const struct krb5_key_test *test)
+{
+	const struct krb5_enctype *krb5 = crypto_krb5_find_enctype(test->etype);
+	struct krb5_buffer base_key = {};
+	int ret;
+
+	if (!krb5)
+		return -EOPNOTSUPP;
+
+	pr_notice("Running %s %s\n", krb5->name, test->name);
+
+	LOAD_BUF(&base_key, test->key);
+
+	ret = krb5_test_key(krb5, &base_key, &test->Kc, TEST_KC);
+	if (ret < 0)
+		goto out;
+	ret = krb5_test_key(krb5, &base_key, &test->Ke, TEST_KE);
+	if (ret < 0)
+		goto out;
+	ret = krb5_test_key(krb5, &base_key, &test->Ki, TEST_KI);
+	if (ret < 0)
+		goto out;
+
+out:
+	clear_buf(&base_key);
+	return ret;
+}
+
+/*
+ * Perform an encryption test.
+ */
+static int krb5_test_one_enc(const struct krb5_enc_test *test, void *buf)
+{
+	const struct krb5_enctype *krb5 = crypto_krb5_find_enctype(test->etype);
+	struct crypto_aead *ci = NULL;
+	struct krb5_buffer K0 = {}, Ke = {}, Ki = {}, keys = {};
+	struct krb5_buffer conf = {}, plain = {}, ct = {};
+	struct scatterlist sg[1];
+	size_t data_len, data_offset, message_len;
+	int ret;
+
+	if (!krb5)
+		return -EOPNOTSUPP;
+
+	pr_notice("Running %s %s\n", krb5->name, test->name);
+
+	/* Load the test data into binary buffers. */
+	LOAD_BUF(&conf, test->conf);
+	LOAD_BUF(&plain, test->plain);
+	LOAD_BUF(&ct, test->ct);
+
+	if (test->K0) {
+		LOAD_BUF(&K0, test->K0);
+	} else {
+		LOAD_BUF(&Ke, test->Ke);
+		LOAD_BUF(&Ki, test->Ki);
+
+		ret = krb5->profile->load_encrypt_keys(krb5, &Ke, &Ki, &keys, GFP_KERNEL);
+		if (ret < 0)
+			goto out;
+	}
+
+	if (VALID(conf.len != krb5->conf_len) ||
+	    VALID(ct.len != krb5->conf_len + plain.len + krb5->cksum_len))
+		goto out;
+
+	data_len = plain.len;
+	message_len = crypto_krb5_how_much_buffer(krb5, KRB5_ENCRYPT_MODE,
+						  data_len, &data_offset);
+
+	if (CHECK(message_len != ct.len)) {
+		pr_warn("Encrypted length mismatch %zu != %u\n", message_len, ct.len);
+		goto out;
+	}
+	if (CHECK(data_offset != conf.len)) {
+		pr_warn("Data offset mismatch %zu != %u\n", data_offset, conf.len);
+		goto out;
+	}
+
+	memcpy(buf, conf.data, conf.len);
+	memcpy(buf + data_offset, plain.data, plain.len);
+
+	/* Allocate a crypto object and set its key. */
+	if (test->K0)
+		ci = crypto_krb5_prepare_encryption(krb5, &K0, test->usage, GFP_KERNEL);
+	else
+		ci = krb5_prepare_encryption(krb5, &keys, GFP_KERNEL);
+
+	if (IS_ERR(ci)) {
+		ret = PTR_ERR(ci);
+		ci = NULL;
+		pr_err("Couldn't alloc AEAD %s: %d\n", krb5->encrypt_name, ret);
+		goto out;
+	}
+
+	/* Encrypt the message. */
+	sg_init_one(sg, buf, message_len);
+	ret = crypto_krb5_encrypt(krb5, ci, sg, 1, message_len,
+				  data_offset, data_len, true);
+	if (ret < 0) {
+		CHECK(1);
+		pr_warn("Encryption failed %d\n", ret);
+		goto out;
+	}
+	if (ret != message_len) {
+		CHECK(1);
+		pr_warn("Encrypted message wrong size %x != %zx\n", ret, message_len);
+		goto out;
+	}
+
+	if (memcmp(buf, ct.data, ct.len) != 0) {
+		CHECK(1);
+		pr_warn("Ciphertext mismatch\n");
+		pr_warn("BUF %*phN\n", ct.len, buf);
+		pr_warn("CT  %*phN\n", ct.len, ct.data);
+		pr_warn("PT  %*phN%*phN\n", conf.len, conf.data, plain.len, plain.data);
+		ret = -EKEYREJECTED;
+		goto out;
+	}
+
+	/* Decrypt the encrypted message. */
+	data_offset = 0;
+	data_len = message_len;
+	ret = crypto_krb5_decrypt(krb5, ci, sg, 1, &data_offset, &data_len);
+	if (ret < 0) {
+		CHECK(1);
+		pr_warn("Decryption failed %d\n", ret);
+		goto out;
+	}
+
+	if (CHECK(data_offset != conf.len) ||
+	    CHECK(data_len != plain.len))
+		goto out;
+
+	if (memcmp(buf, conf.data, conf.len) != 0) {
+		CHECK(1);
+		pr_warn("Confounder mismatch\n");
+		pr_warn("ENC %*phN\n", conf.len, buf);
+		pr_warn("DEC %*phN\n", conf.len, conf.data);
+		ret = -EKEYREJECTED;
+		goto out;
+	}
+
+	if (memcmp(buf + conf.len, plain.data, plain.len) != 0) {
+		CHECK(1);
+		pr_warn("Plaintext mismatch\n");
+		pr_warn("BUF %*phN\n", plain.len, buf + conf.len);
+		pr_warn("PT  %*phN\n", plain.len, plain.data);
+		ret = -EKEYREJECTED;
+		goto out;
+	}
+
+	ret = 0;
+
+out:
+	clear_buf(&ct);
+	clear_buf(&plain);
+	clear_buf(&conf);
+	clear_buf(&keys);
+	clear_buf(&Ki);
+	clear_buf(&Ke);
+	clear_buf(&K0);
+	if (ci)
+		crypto_free_aead(ci);
+	return ret;
+}
+
+/*
+ * Perform a checksum test.
+ */
+static int krb5_test_one_mic(const struct krb5_mic_test *test, void *buf)
+{
+	const struct krb5_enctype *krb5 = crypto_krb5_find_enctype(test->etype);
+	struct crypto_shash *ci = NULL;
+	struct scatterlist sg[1];
+	struct krb5_buffer K0 = {}, Kc = {}, keys = {}, plain = {}, mic = {};
+	size_t offset, len, message_len;
+	int ret;
+
+	if (!krb5)
+		return -EOPNOTSUPP;
+
+	pr_notice("Running %s %s\n", krb5->name, test->name);
+
+	/* Allocate a crypto object and set its key. */
+	if (test->K0) {
+		LOAD_BUF(&K0, test->K0);
+		ci = crypto_krb5_prepare_checksum(krb5, &K0, test->usage, GFP_KERNEL);
+	} else {
+		LOAD_BUF(&Kc, test->Kc);
+
+		ret = krb5->profile->load_checksum_key(krb5, &Kc, &keys, GFP_KERNEL);
+		if (ret < 0)
+			goto out;
+
+		ci = krb5_prepare_checksum(krb5, &Kc, GFP_KERNEL);
+	}
+	if (IS_ERR(ci)) {
+		ret = PTR_ERR(ci);
+		ci = NULL;
+		pr_err("Couldn't alloc shash %s: %d\n", krb5->cksum_name, ret);
+		goto out;
+	}
+
+	/* Load the test data into binary buffers. */
+	LOAD_BUF(&plain, test->plain);
+	LOAD_BUF(&mic, test->mic);
+
+	len = plain.len;
+	message_len = crypto_krb5_how_much_buffer(krb5, KRB5_CHECKSUM_MODE,
+						  len, &offset);
+
+	if (CHECK(message_len != mic.len + plain.len)) {
+		pr_warn("MIC length mismatch %zu != %u\n",
+			message_len, mic.len + plain.len);
+		goto out;
+	}
+
+	memcpy(buf + offset, plain.data, plain.len);
+
+	/* Generate a MIC generation request. */
+	sg_init_one(sg, buf, 1024);
+
+	ret = crypto_krb5_get_mic(krb5, ci, NULL, sg, 1, 1024,
+				  krb5->cksum_len, plain.len);
+	if (ret < 0) {
+		CHECK(1);
+		pr_warn("Get MIC failed %d\n", ret);
+		goto out;
+	}
+	len = ret;
+
+	if (CHECK(len != plain.len + mic.len)) {
+		pr_warn("MIC length mismatch %zu != %u\n", len, plain.len + mic.len);
+		goto out;
+	}
+
+	if (memcmp(buf, mic.data, mic.len) != 0) {
+		CHECK(1);
+		pr_warn("MIC mismatch\n");
+		pr_warn("BUF %*phN\n", mic.len, buf);
+		pr_warn("MIC %*phN\n", mic.len, mic.data);
+		ret = -EKEYREJECTED;
+		goto out;
+	}
+
+	/* Generate a verification request. */
+	offset = 0;
+	ret = crypto_krb5_verify_mic(krb5, ci, NULL, sg, 1, &offset, &len);
+	if (ret < 0) {
+		CHECK(1);
+		pr_warn("Verify MIC failed %d\n", ret);
+		goto out;
+	}
+
+	if (CHECK(offset != mic.len) ||
+	    CHECK(len != plain.len))
+		goto out;
+
+	if (memcmp(buf + offset, plain.data, plain.len) != 0) {
+		CHECK(1);
+		pr_warn("Plaintext mismatch\n");
+		pr_warn("BUF %*phN\n", plain.len, buf + offset);
+		pr_warn("PT  %*phN\n", plain.len, plain.data);
+		ret = -EKEYREJECTED;
+		goto out;
+	}
+
+	ret = 0;
+
+out:
+	clear_buf(&mic);
+	clear_buf(&plain);
+	clear_buf(&keys);
+	clear_buf(&K0);
+	clear_buf(&Kc);
+	if (ci)
+		crypto_free_shash(ci);
+	return ret;
+}
+
+int krb5_selftest(void)
+{
+	void *buf;
+	int ret = 0, i;
+
+	buf = kmalloc(4096, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	pr_notice("\n");
+	pr_notice("Running selftests\n");
+
+	for (i = 0; krb5_prf_tests[i].name; i++) {
+		ret = krb5_test_one_prf(&krb5_prf_tests[i]);
+		if (ret < 0) {
+			if (ret != -EOPNOTSUPP)
+				goto out;
+			pr_notice("Skipping %s\n", krb5_prf_tests[i].name);
+		}
+	}
+
+	for (i = 0; krb5_key_tests[i].name; i++) {
+		ret = krb5_test_one_key(&krb5_key_tests[i]);
+		if (ret < 0) {
+			if (ret != -EOPNOTSUPP)
+				goto out;
+			pr_notice("Skipping %s\n", krb5_key_tests[i].name);
+		}
+	}
+
+	for (i = 0; krb5_enc_tests[i].name; i++) {
+		memset(buf, 0x5a, 4096);
+		ret = krb5_test_one_enc(&krb5_enc_tests[i], buf);
+		if (ret < 0) {
+			if (ret != -EOPNOTSUPP)
+				goto out;
+			pr_notice("Skipping %s\n", krb5_enc_tests[i].name);
+		}
+	}
+
+	for (i = 0; krb5_mic_tests[i].name; i++) {
+		memset(buf, 0x5a, 4096);
+		ret = krb5_test_one_mic(&krb5_mic_tests[i], buf);
+		if (ret < 0) {
+			if (ret != -EOPNOTSUPP)
+				goto out;
+			pr_notice("Skipping %s\n", krb5_mic_tests[i].name);
+		}
+	}
+
+	ret = 0;
+out:
+	pr_notice("Selftests %s\n", ret == 0 ? "succeeded" : "failed");
+	kfree(buf);
+	return ret;
+}
diff --git a/crypto/krb5/selftest_data.c b/crypto/krb5/selftest_data.c
new file mode 100644
index 000000000000..bef5b8b342ae
--- /dev/null
+++ b/crypto/krb5/selftest_data.c
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Data for Kerberos library self-testing
+ *
+ * Copyright (C) 2025 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include "internal.h"
+
+/*
+ * Pseudo-random function tests.
+ */
+const struct krb5_prf_test krb5_prf_tests[] = {
+	{/* END */}
+};
+
+/*
+ * Key derivation tests.
+ */
+const struct krb5_key_test krb5_key_tests[] = {
+	{/* END */}
+};
+
+/*
+ * Encryption tests.
+ */
+const struct krb5_enc_test krb5_enc_tests[] = {
+	{/* END */}
+};
+
+/*
+ * Checksum generation tests.
+ */
+const struct krb5_mic_test krb5_mic_tests[] = {
+	{/* END */}
+};

[RFC PATCH 18/24] crypto/krb5: Add the AES self-testing data from rfc8009

[David Howells]

Add the self-testing data from rfc8009 to test AES + HMAC-SHA2.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/krb5/selftest_data.c | 118 ++++++++++++++++++++++++++++++++++++
 1 file changed, 118 insertions(+)

diff --git a/crypto/krb5/selftest_data.c b/crypto/krb5/selftest_data.c
index bef5b8b342ae..3a5563d57280 100644
--- a/crypto/krb5/selftest_data.c
+++ b/crypto/krb5/selftest_data.c
@@ -13,6 +13,22 @@
  * Pseudo-random function tests.
  */
 const struct krb5_prf_test krb5_prf_tests[] = {
+	/* rfc8009 Appendix A */
+	{
+		.etype	= KRB5_ENCTYPE_AES128_CTS_HMAC_SHA256_128,
+		.name	= "prf",
+		.key	= "3705D96080C17728A0E800EAB6E0D23C",
+		.octet	= "74657374",
+		.prf	= "9D188616F63852FE86915BB840B4A886FF3E6BB0F819B49B893393D393854295",
+	}, {
+		.etype	= KRB5_ENCTYPE_AES256_CTS_HMAC_SHA384_192,
+		.name	= "prf",
+		.key	= "6D404D37FAF79F9DF0D33568D320669800EB4836472EA8A026D16B7182460C52",
+		.octet	= "74657374",
+		.prf	=
+		"9801F69A368C2BF675E59521E177D9A07F67EFE1CFDE8D3C8D6F6A0256E3B17D"
+		"B3C1B62AD1B8553360D17367EB1514D2",
+	},
 	{/* END */}
 };
 
@@ -20,6 +36,28 @@ const struct krb5_prf_test krb5_prf_tests[] = {
  * Key derivation tests.
  */
 const struct krb5_key_test krb5_key_tests[] = {
+	/* rfc8009 Appendix A */
+	{
+		.etype	= KRB5_ENCTYPE_AES128_CTS_HMAC_SHA256_128,
+		.name	= "key",
+		.key	= "3705D96080C17728A0E800EAB6E0D23C",
+		.Kc.use	= 0x00000002,
+		.Kc.key	= "B31A018A48F54776F403E9A396325DC3",
+		.Ke.use	= 0x00000002,
+		.Ke.key	= "9B197DD1E8C5609D6E67C3E37C62C72E",
+		.Ki.use	= 0x00000002,
+		.Ki.key	= "9FDA0E56AB2D85E1569A688696C26A6C",
+	}, {
+		.etype	= KRB5_ENCTYPE_AES256_CTS_HMAC_SHA384_192,
+		.name	= "key",
+		.key	= "6D404D37FAF79F9DF0D33568D320669800EB4836472EA8A026D16B7182460C52",
+		.Kc.use	= 0x00000002,
+		.Kc.key	= "EF5718BE86CC84963D8BBB5031E9F5C4BA41F28FAF69E73D",
+		.Ke.use	= 0x00000002,
+		.Ke.key	= "56AB22BEE63D82D7BC5227F6773F8EA7A5EB1C825160C38312980C442E5C7E49",
+		.Ki.use	= 0x00000002,
+		.Ki.key	= "69B16514E3CD8E56B82010D5C73012B622C4D00FFC23ED1F",
+	},
 	{/* END */}
 };
 
@@ -27,6 +65,72 @@ const struct krb5_key_test krb5_key_tests[] = {
  * Encryption tests.
  */
 const struct krb5_enc_test krb5_enc_tests[] = {
+	/* rfc8009 Appendix A */
+	{
+		.etype	= KRB5_ENCTYPE_AES128_CTS_HMAC_SHA256_128,
+		.name	= "enc no plain",
+		.plain	= "",
+		.conf	= "7E5895EAF2672435BAD817F545A37148",
+		.Ke	= "9B197DD1E8C5609D6E67C3E37C62C72E",
+		.Ki	= "9FDA0E56AB2D85E1569A688696C26A6C",
+		.ct	= "EF85FB890BB8472F4DAB20394DCA781DAD877EDA39D50C870C0D5A0A8E48C718",
+	}, {
+		.etype	= KRB5_ENCTYPE_AES128_CTS_HMAC_SHA256_128,
+		.name	= "enc plain<block",
+		.plain	= "000102030405",
+		.conf	= "7BCA285E2FD4130FB55B1A5C83BC5B24",
+		.Ke	= "9B197DD1E8C5609D6E67C3E37C62C72E",
+		.Ki	= "9FDA0E56AB2D85E1569A688696C26A6C",
+		.ct	= "84D7F30754ED987BAB0BF3506BEB09CFB55402CEF7E6877CE99E247E52D16ED4421DFDF8976C",
+	}, {
+		.etype	= KRB5_ENCTYPE_AES128_CTS_HMAC_SHA256_128,
+		.name	= "enc plain==block",
+		.plain	= "000102030405060708090A0B0C0D0E0F",
+		.conf	= "56AB21713FF62C0A1457200F6FA9948F",
+		.Ke	= "9B197DD1E8C5609D6E67C3E37C62C72E",
+		.Ki	= "9FDA0E56AB2D85E1569A688696C26A6C",
+		.ct	= "3517D640F50DDC8AD3628722B3569D2AE07493FA8263254080EA65C1008E8FC295FB4852E7D83E1E7C48C37EEBE6B0D3",
+	}, {
+		.etype	= KRB5_ENCTYPE_AES128_CTS_HMAC_SHA256_128,
+		.name	= "enc plain>block",
+		.plain	= "000102030405060708090A0B0C0D0E0F1011121314",
+		.conf	= "A7A4E29A4728CE10664FB64E49AD3FAC",
+		.Ke	= "9B197DD1E8C5609D6E67C3E37C62C72E",
+		.Ki	= "9FDA0E56AB2D85E1569A688696C26A6C",
+		.ct	= "720F73B18D9859CD6CCB4346115CD336C70F58EDC0C4437C5573544C31C813BCE1E6D072C186B39A413C2F92CA9B8334A287FFCBFC",
+	}, {
+		.etype	= KRB5_ENCTYPE_AES256_CTS_HMAC_SHA384_192,
+		.name	= "enc no plain",
+		.plain	= "",
+		.conf	= "F764E9FA15C276478B2C7D0C4E5F58E4",
+		.Ke	= "56AB22BEE63D82D7BC5227F6773F8EA7A5EB1C825160C38312980C442E5C7E49",
+		.Ki	= "69B16514E3CD8E56B82010D5C73012B622C4D00FFC23ED1F",
+		.ct	= "41F53FA5BFE7026D91FAF9BE959195A058707273A96A40F0A01960621AC612748B9BBFBE7EB4CE3C",
+	}, {
+		.etype	= KRB5_ENCTYPE_AES256_CTS_HMAC_SHA384_192,
+		.name	= "enc plain<block",
+		.plain	= "000102030405",
+		.conf	= "B80D3251C1F6471494256FFE712D0B9A",
+		.Ke	= "56AB22BEE63D82D7BC5227F6773F8EA7A5EB1C825160C38312980C442E5C7E49",
+		.Ki	= "69B16514E3CD8E56B82010D5C73012B622C4D00FFC23ED1F",
+		.ct	= "4ED7B37C2BCAC8F74F23C1CF07E62BC7B75FB3F637B9F559C7F664F69EAB7B6092237526EA0D1F61CB20D69D10F2",
+	}, {
+		.etype	= KRB5_ENCTYPE_AES256_CTS_HMAC_SHA384_192,
+		.name	= "enc plain==block",
+		.plain	= "000102030405060708090A0B0C0D0E0F",
+		.conf	= "53BF8A0D105265D4E276428624CE5E63",
+		.Ke	= "56AB22BEE63D82D7BC5227F6773F8EA7A5EB1C825160C38312980C442E5C7E49",
+		.Ki	= "69B16514E3CD8E56B82010D5C73012B622C4D00FFC23ED1F",
+		.ct	= "BC47FFEC7998EB91E8115CF8D19DAC4BBBE2E163E87DD37F49BECA92027764F68CF51F14D798C2273F35DF574D1F932E40C4FF255B36A266",
+	}, {
+		.etype	= KRB5_ENCTYPE_AES256_CTS_HMAC_SHA384_192,
+		.name	= "enc plain>block",
+		.plain	= "000102030405060708090A0B0C0D0E0F1011121314",
+		.conf	= "763E65367E864F02F55153C7E3B58AF1",
+		.Ke	= "56AB22BEE63D82D7BC5227F6773F8EA7A5EB1C825160C38312980C442E5C7E49",
+		.Ki	= "69B16514E3CD8E56B82010D5C73012B622C4D00FFC23ED1F",
+		.ct	= "40013E2DF58E8751957D2878BCD2D6FE101CCFD556CB1EAE79DB3C3EE86429F2B2A602AC86FEF6ECB647D6295FAE077A1FEB517508D2C16B4192E01F62",
+	},
 	{/* END */}
 };
 
@@ -34,5 +138,19 @@ const struct krb5_enc_test krb5_enc_tests[] = {
  * Checksum generation tests.
  */
 const struct krb5_mic_test krb5_mic_tests[] = {
+	/* rfc8009 Appendix A */
+	{
+		.etype	= KRB5_ENCTYPE_AES128_CTS_HMAC_SHA256_128,
+		.name	= "mic",
+		.plain	= "000102030405060708090A0B0C0D0E0F1011121314",
+		.Kc	= "B31A018A48F54776F403E9A396325DC3",
+		.mic	= "D78367186643D67B411CBA9139FC1DEE",
+	}, {
+		.etype	= KRB5_ENCTYPE_AES256_CTS_HMAC_SHA384_192,
+		.name	= "mic",
+		.plain	= "000102030405060708090A0B0C0D0E0F1011121314",
+		.Kc	= "EF5718BE86CC84963D8BBB5031E9F5C4BA41F28FAF69E73D",
+		.mic	= "45EE791567EEFCA37F4AC1E0222DE80D43C3BFA06699672A",
+	},
 	{/* END */}
 };

[RFC PATCH 19/24] crypto/krb5: Implement the Camellia enctypes from rfc6803

[David Howells]

Implement the camellia128-cts-cmac and camellia256-cts-cmac enctypes from
rfc6803.

Note that the test vectors in rfc6803 for encryption are incomplete,
lacking the key usage number needed to derive Ke and Ki, and there are
errata for this:

	https://www.rfc-editor.org/errata_search.php?rfc=6803

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-nfs@vger.kernel.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 crypto/krb5/Kconfig            |   2 +
 crypto/krb5/Makefile           |   1 +
 crypto/krb5/internal.h         |   6 +
 crypto/krb5/krb5_api.c         |   2 +
 crypto/krb5/rfc6803_camellia.c | 237 +++++++++++++++++++++++++++++++++
 crypto/krb5/selftest_data.c    | 135 +++++++++++++++++++
 include/crypto/krb5.h          |   4 +
 7 files changed, 387 insertions(+)
 create mode 100644 crypto/krb5/rfc6803_camellia.c

diff --git a/crypto/krb5/Kconfig b/crypto/krb5/Kconfig
index 82d7e3b55878..4d0476e13f3c 100644
--- a/crypto/krb5/Kconfig
+++ b/crypto/krb5/Kconfig
@@ -6,12 +6,14 @@ config CRYPTO_KRB5
 	select CRYPTO_SKCIPHER
 	select CRYPTO_HASH_INFO
 	select CRYPTO_HMAC
+	select CRYPTO_CMAC
 	select CRYPTO_SHA1
 	select CRYPTO_SHA256
 	select CRYPTO_SHA512
 	select CRYPTO_CBC
 	select CRYPTO_CTS
 	select CRYPTO_AES
+	select CRYPTO_CAMELLIA
 	help
 	  Provide a library for provision of Kerberos-5-based crypto.  This is
 	  intended for network filesystems to use.
diff --git a/crypto/krb5/Makefile b/crypto/krb5/Makefile
index 1ad327227744..d38890c0b247 100644
--- a/crypto/krb5/Makefile
+++ b/crypto/krb5/Makefile
@@ -8,6 +8,7 @@ krb5-y += \
 	krb5_api.o \
 	rfc3961_simplified.o \
 	rfc3962_aes.o \
+	rfc6803_camellia.o \
 	rfc8009_aes2.o
 
 krb5-$(CONFIG_CRYPTO_KRB5_SELFTESTS) += \
diff --git a/crypto/krb5/internal.h b/crypto/krb5/internal.h
index a40f120b4954..0a7ecd800416 100644
--- a/crypto/krb5/internal.h
+++ b/crypto/krb5/internal.h
@@ -217,6 +217,12 @@ int rfc3961_verify_mic(const struct krb5_enctype *krb5,
 extern const struct krb5_enctype krb5_aes128_cts_hmac_sha1_96;
 extern const struct krb5_enctype krb5_aes256_cts_hmac_sha1_96;
 
+/*
+ * rfc6803_camellia.c
+ */
+extern const struct krb5_enctype krb5_camellia128_cts_cmac;
+extern const struct krb5_enctype krb5_camellia256_cts_cmac;
+
 /*
  * rfc8009_aes2.c
  */
diff --git a/crypto/krb5/krb5_api.c b/crypto/krb5/krb5_api.c
index 8c2949ac9c07..23026d4206c8 100644
--- a/crypto/krb5/krb5_api.c
+++ b/crypto/krb5/krb5_api.c
@@ -21,6 +21,8 @@ static const struct krb5_enctype *const krb5_supported_enctypes[] = {
 	&krb5_aes256_cts_hmac_sha1_96,
 	&krb5_aes128_cts_hmac_sha256_128,
 	&krb5_aes256_cts_hmac_sha384_192,
+	&krb5_camellia128_cts_cmac,
+	&krb5_camellia256_cts_cmac,
 };
 
 /**
diff --git a/crypto/krb5/rfc6803_camellia.c b/crypto/krb5/rfc6803_camellia.c
new file mode 100644
index 000000000000..c2895d2d60ed
--- /dev/null
+++ b/crypto/krb5/rfc6803_camellia.c
@@ -0,0 +1,237 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* rfc6803 Camellia Encryption for Kerberos 5
+ *
+ * Copyright (C) 2025 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/slab.h>
+#include "internal.h"
+
+/*
+ * Calculate the key derivation function KDF-FEEDBACK_CMAC(key, constant)
+ *
+ *	n = ceiling(k / 128)
+ *	K(0) = zeros
+ *	K(i) = CMAC(key, K(i-1) | i | constant | 0x00 | k)
+ *	DR(key, constant) = k-truncate(K(1) | K(2) | ... | K(n))
+ *	KDF-FEEDBACK-CMAC(key, constant) = random-to-key(DR(key, constant))
+ *
+ *	[rfc6803 sec 3]
+ */
+static int rfc6803_calc_KDF_FEEDBACK_CMAC(const struct krb5_enctype *krb5,
+					  const struct krb5_buffer *key,
+					  const struct krb5_buffer *constant,
+					  struct krb5_buffer *result,
+					  gfp_t gfp)
+{
+	struct crypto_shash *shash;
+	struct krb5_buffer K, data;
+	struct shash_desc *desc;
+	__be32 tmp;
+	size_t bsize, offset, seg;
+	void *buffer;
+	u32 i = 0, k = result->len * 8;
+	u8 *p;
+	int ret = -ENOMEM;
+
+	shash = crypto_alloc_shash(krb5->cksum_name, 0, 0);
+	if (IS_ERR(shash))
+		return (PTR_ERR(shash) == -ENOENT) ? -ENOPKG : PTR_ERR(shash);
+	ret = crypto_shash_setkey(shash, key->data, key->len);
+	if (ret < 0)
+		goto error_shash;
+
+	ret = -ENOMEM;
+	K.len = crypto_shash_digestsize(shash);
+	data.len = K.len + 4 + constant->len + 1 + 4;
+	bsize = krb5_shash_size(shash) +
+		krb5_digest_size(shash) +
+		crypto_roundup(K.len) +
+		crypto_roundup(data.len);
+	buffer = kzalloc(bsize, GFP_NOFS);
+	if (!buffer)
+		goto error_shash;
+
+	desc = buffer;
+	desc->tfm = shash;
+
+	K.data = buffer +
+		krb5_shash_size(shash) +
+		krb5_digest_size(shash);
+	data.data = buffer +
+		krb5_shash_size(shash) +
+		krb5_digest_size(shash) +
+		crypto_roundup(K.len);
+
+	p = data.data + K.len + 4;
+	memcpy(p, constant->data, constant->len);
+	p += constant->len;
+	*p++ = 0x00;
+	tmp = htonl(k);
+	memcpy(p, &tmp, 4);
+	p += 4;
+
+	ret = -EINVAL;
+	if (WARN_ON(p - (u8 *)data.data != data.len))
+		goto error;
+
+	offset = 0;
+	do {
+		i++;
+		p = data.data;
+		memcpy(p, K.data, K.len);
+		p += K.len;
+		*(__be32 *)p = htonl(i);
+
+		ret = crypto_shash_init(desc);
+		if (ret < 0)
+			goto error;
+		ret = crypto_shash_finup(desc, data.data, data.len, K.data);
+		if (ret < 0)
+			goto error;
+
+		seg = min_t(size_t, result->len - offset, K.len);
+		memcpy(result->data + offset, K.data, seg);
+		offset += seg;
+	} while (offset < result->len);
+
+error:
+	kfree_sensitive(buffer);
+error_shash:
+	crypto_free_shash(shash);
+	return ret;
+}
+
+/*
+ * Calculate the pseudo-random function, PRF().
+ *
+ *	Kp = KDF-FEEDBACK-CMAC(protocol-key, "prf")
+ *	PRF = CMAC(Kp, octet-string)
+ *      [rfc6803 sec 6]
+ */
+static int rfc6803_calc_PRF(const struct krb5_enctype *krb5,
+			    const struct krb5_buffer *protocol_key,
+			    const struct krb5_buffer *octet_string,
+			    struct krb5_buffer *result,
+			    gfp_t gfp)
+{
+	static const struct krb5_buffer prfconstant = { 3, "prf" };
+	struct crypto_shash *shash;
+	struct krb5_buffer Kp;
+	struct shash_desc *desc;
+	size_t bsize;
+	void *buffer;
+	int ret;
+
+	Kp.len = krb5->prf_len;
+
+	shash = crypto_alloc_shash(krb5->cksum_name, 0, 0);
+	if (IS_ERR(shash))
+		return (PTR_ERR(shash) == -ENOENT) ? -ENOPKG : PTR_ERR(shash);
+
+	ret = -EINVAL;
+	if (result->len != crypto_shash_digestsize(shash))
+		goto out_shash;
+
+	ret = -ENOMEM;
+	bsize = krb5_shash_size(shash) +
+		krb5_digest_size(shash) +
+		crypto_roundup(Kp.len);
+	buffer = kzalloc(bsize, GFP_NOFS);
+	if (!buffer)
+		goto out_shash;
+
+	Kp.data = buffer +
+		krb5_shash_size(shash) +
+		krb5_digest_size(shash);
+
+	ret = rfc6803_calc_KDF_FEEDBACK_CMAC(krb5, protocol_key, &prfconstant,
+					     &Kp, gfp);
+	if (ret < 0)
+		goto out;
+
+	ret = crypto_shash_setkey(shash, Kp.data, Kp.len);
+	if (ret < 0)
+		goto out;
+
+	desc = buffer;
+	desc->tfm = shash;
+	ret = crypto_shash_init(desc);
+	if (ret < 0)
+		goto out;
+
+	ret = crypto_shash_finup(desc, octet_string->data, octet_string->len, result->data);
+	if (ret < 0)
+		goto out;
+
+out:
+	kfree_sensitive(buffer);
+out_shash:
+	crypto_free_shash(shash);
+	return ret;
+}
+
+
+static const struct krb5_crypto_profile rfc6803_crypto_profile = {
+	.calc_PRF		= rfc6803_calc_PRF,
+	.calc_Kc		= rfc6803_calc_KDF_FEEDBACK_CMAC,
+	.calc_Ke		= rfc6803_calc_KDF_FEEDBACK_CMAC,
+	.calc_Ki		= rfc6803_calc_KDF_FEEDBACK_CMAC,
+	.derive_encrypt_keys	= krb5enc_derive_encrypt_keys,
+	.load_encrypt_keys	= krb5enc_load_encrypt_keys,
+	.derive_checksum_key	= rfc3961_derive_checksum_key,
+	.load_checksum_key	= rfc3961_load_checksum_key,
+	.encrypt		= krb5_aead_encrypt,
+	.decrypt		= krb5_aead_decrypt,
+	.get_mic		= rfc3961_get_mic,
+	.verify_mic		= rfc3961_verify_mic,
+};
+
+const struct krb5_enctype krb5_camellia128_cts_cmac = {
+	.etype		= KRB5_ENCTYPE_CAMELLIA128_CTS_CMAC,
+	.ctype		= KRB5_CKSUMTYPE_CMAC_CAMELLIA128,
+	.name		= "camellia128-cts-cmac",
+	.encrypt_name	= "krb5enc(cmac(camellia),cts(cbc(camellia)))",
+	.cksum_name	= "cmac(camellia)",
+	.hash_name	= NULL,
+	.derivation_enc	= "cts(cbc(camellia))",
+	.key_bytes	= 16,
+	.key_len	= 16,
+	.Kc_len		= 16,
+	.Ke_len		= 16,
+	.Ki_len		= 16,
+	.block_len	= 16,
+	.conf_len	= 16,
+	.cksum_len	= 16,
+	.hash_len	= 16,
+	.prf_len	= 16,
+	.keyed_cksum	= true,
+	.random_to_key	= NULL, /* Identity */
+	.profile	= &rfc6803_crypto_profile,
+};
+
+const struct krb5_enctype krb5_camellia256_cts_cmac = {
+	.etype		= KRB5_ENCTYPE_CAMELLIA256_CTS_CMAC,
+	.ctype		= KRB5_CKSUMTYPE_CMAC_CAMELLIA256,
+	.name		= "camellia256-cts-cmac",
+	.encrypt_name	= "krb5enc(cmac(camellia),cts(cbc(camellia)))",
+	.cksum_name	= "cmac(camellia)",
+	.hash_name	= NULL,
+	.derivation_enc	= "cts(cbc(camellia))",
+	.key_bytes	= 32,
+	.key_len	= 32,
+	.Kc_len		= 32,
+	.Ke_len		= 32,
+	.Ki_len		= 32,
+	.block_len	= 16,
+	.conf_len	= 16,
+	.cksum_len	= 16,
+	.hash_len	= 16,
+	.prf_len	= 16,
+	.keyed_cksum	= true,
+	.random_to_key	= NULL, /* Identity */
+	.profile	= &rfc6803_crypto_profile,
+};
diff --git a/crypto/krb5/selftest_data.c b/crypto/krb5/selftest_data.c
index 3a5563d57280..24447ee8bf07 100644
--- a/crypto/krb5/selftest_data.c
+++ b/crypto/krb5/selftest_data.c
@@ -58,6 +58,29 @@ const struct krb5_key_test krb5_key_tests[] = {
 		.Ki.use	= 0x00000002,
 		.Ki.key	= "69B16514E3CD8E56B82010D5C73012B622C4D00FFC23ED1F",
 	},
+	/* rfc6803 sec 10 */
+	{
+		.etype	= KRB5_ENCTYPE_CAMELLIA128_CTS_CMAC,
+		.name	= "key",
+		.key	= "57D0297298FFD9D35DE5A47FB4BDE24B",
+		.Kc.use	= 0x00000002,
+		.Kc.key	= "D155775A209D05F02B38D42A389E5A56",
+		.Ke.use	= 0x00000002,
+		.Ke.key	= "64DF83F85A532F17577D8C37035796AB",
+		.Ki.use	= 0x00000002,
+		.Ki.key	= "3E4FBDF30FB8259C425CB6C96F1F4635",
+	},
+	{
+		.etype	= KRB5_ENCTYPE_CAMELLIA256_CTS_CMAC,
+		.name	= "key",
+		.key	= "B9D6828B2056B7BE656D88A123B1FAC68214AC2B727ECF5F69AFE0C4DF2A6D2C",
+		.Kc.use	= 0x00000002,
+		.Kc.key	= "E467F9A9552BC7D3155A6220AF9C19220EEED4FF78B0D1E6A1544991461A9E50",
+		.Ke.use	= 0x00000002,
+		.Ke.key	= "412AEFC362A7285FC3966C6A5181E7605AE675235B6D549FBFC9AB6630A4C604",
+		.Ki.use	= 0x00000002,
+		.Ki.key	= "FA624FA0E523993FA388AEFDC67E67EBCD8C08E8A0246B1D73B0D1DD9FC582B0",
+	},
 	{/* END */}
 };
 
@@ -131,6 +154,88 @@ const struct krb5_enc_test krb5_enc_tests[] = {
 		.Ki	= "69B16514E3CD8E56B82010D5C73012B622C4D00FFC23ED1F",
 		.ct	= "40013E2DF58E8751957D2878BCD2D6FE101CCFD556CB1EAE79DB3C3EE86429F2B2A602AC86FEF6ECB647D6295FAE077A1FEB517508D2C16B4192E01F62",
 	},
+	/* rfc6803 sec 10 */
+	{
+		.etype	= KRB5_ENCTYPE_CAMELLIA128_CTS_CMAC,
+		.name	= "enc no plain",
+		.plain	= "",
+		.conf	= "B69822A19A6B09C0EBC8557D1F1B6C0A",
+		.K0	= "1DC46A8D763F4F93742BCBA3387576C3",
+		.usage	= 0,
+		.ct	= "C466F1871069921EDB7C6FDE244A52DB0BA10EDC197BDB8006658CA3CCCE6EB8",
+	}, {
+		.etype	= KRB5_ENCTYPE_CAMELLIA128_CTS_CMAC,
+		.name	= "enc 1 plain",
+		.plain	= "'1",
+		.conf	= "6F2FC3C2A166FD8898967A83DE9596D9",
+		.K0	= "5027BC231D0F3A9D23333F1CA6FDBE7C",
+		.usage	= 1,
+		.ct	= "842D21FD950311C0DD464A3F4BE8D6DA88A56D559C9B47D3F9A85067AF661559B8",
+	}, {
+		.etype	= KRB5_ENCTYPE_CAMELLIA128_CTS_CMAC,
+		.name	= "enc 9 plain",
+		.plain	= "'9 bytesss",
+		.conf	= "A5B4A71E077AEEF93C8763C18FDB1F10",
+		.K0	= "A1BB61E805F9BA6DDE8FDBDDC05CDEA0",
+		.usage	= 2,
+		.ct	= "619FF072E36286FF0A28DEB3A352EC0D0EDF5C5160D663C901758CCF9D1ED33D71DB8F23AABF8348A0",
+	}, {
+		.etype	= KRB5_ENCTYPE_CAMELLIA128_CTS_CMAC,
+		.name	= "enc 13 plain",
+		.plain	= "'13 bytes byte",
+		.conf	= "19FEE40D810C524B5B22F01874C693DA",
+		.K0	= "2CA27A5FAF5532244506434E1CEF6676",
+		.usage	= 3,
+		.ct	= "B8ECA3167AE6315512E59F98A7C500205E5F63FF3BB389AF1C41A21D640D8615C9ED3FBEB05AB6ACB67689B5EA",
+	}, {
+		.etype	= KRB5_ENCTYPE_CAMELLIA128_CTS_CMAC,
+		.name	= "enc 30 plain",
+		.plain	= "'30 bytes bytes bytes bytes byt",
+		.conf	= "CA7A7AB4BE192DABD603506DB19C39E2",
+		.K0	= "7824F8C16F83FF354C6BF7515B973F43",
+		.usage	= 4,
+		.ct	= "A26A3905A4FFD5816B7B1E27380D08090C8EC1F304496E1ABDCD2BDCD1DFFC660989E117A713DDBB57A4146C1587CBA4356665591D2240282F5842B105A5",
+	}, {
+		.etype	= KRB5_ENCTYPE_CAMELLIA256_CTS_CMAC,
+		.name	= "enc no plain",
+		.plain	= "",
+		.conf	= "3CBBD2B45917941067F96599BB98926C",
+		.K0	= "B61C86CC4E5D2757545AD423399FB7031ECAB913CBB900BD7A3C6DD8BF92015B",
+		.usage	= 0,
+		.ct	= "03886D03310B47A6D8F06D7B94D1DD837ECCE315EF652AFF620859D94A259266",
+	}, {
+		.etype	= KRB5_ENCTYPE_CAMELLIA256_CTS_CMAC,
+		.name	= "enc 1 plain",
+		.plain	= "'1",
+		.conf	= "DEF487FCEBE6DE6346D4DA4521BBA2D2",
+		.K0	= "1B97FE0A190E2021EB30753E1B6E1E77B0754B1D684610355864104963463833",
+		.usage	= 1,
+		.ct	= "2C9C1570133C99BF6A34BC1B0212002FD194338749DB4135497A347CFCD9D18A12",
+	}, {
+		.etype	= KRB5_ENCTYPE_CAMELLIA256_CTS_CMAC,
+		.name	= "enc 9 plain",
+		.plain	= "'9 bytesss",
+		.conf	= "AD4FF904D34E555384B14100FC465F88",
+		.K0	= "32164C5B434D1D1538E4CFD9BE8040FE8C4AC7ACC4B93D3314D2133668147A05",
+		.usage	= 2,
+		.ct	= "9C6DE75F812DE7ED0D28B2963557A115640998275B0AF5152709913FF52A2A9C8E63B872F92E64C839",
+	}, {
+		.etype	= KRB5_ENCTYPE_CAMELLIA256_CTS_CMAC,
+		.name	= "enc 13 plain",
+		.plain	= "'13 bytes byte",
+		.conf	= "CF9BCA6DF1144E0C0AF9B8F34C90D514",
+		.K0	= "B038B132CD8E06612267FAB7170066D88AECCBA0B744BFC60DC89BCA182D0715",
+		.usage	= 3,
+		.ct	= "EEEC85A9813CDC536772AB9B42DEFC5706F726E975DDE05A87EB5406EA324CA185C9986B42AABE794B84821BEE",
+	}, {
+		.etype	= KRB5_ENCTYPE_CAMELLIA256_CTS_CMAC,
+		.name	= "enc 30 plain",
+		.plain	= "'30 bytes bytes bytes bytes byt",
+		.conf	= "644DEF38DA35007275878D216855E228",
+		.K0	= "CCFCD349BF4C6677E86E4B02B8EAB924A546AC731CF9BF6989B996E7D6BFBBA7",
+		.usage	= 4,
+		.ct	= "0E44680985855F2D1F1812529CA83BFD8E349DE6FD9ADA0BAAA048D68E265FEBF34AD1255A344999AD37146887A6C6845731AC7F46376A0504CD06571474",
+	},
 	{/* END */}
 };
 
@@ -152,5 +257,35 @@ const struct krb5_mic_test krb5_mic_tests[] = {
 		.Kc	= "EF5718BE86CC84963D8BBB5031E9F5C4BA41F28FAF69E73D",
 		.mic	= "45EE791567EEFCA37F4AC1E0222DE80D43C3BFA06699672A",
 	},
+	/* rfc6803 sec 10 */
+	{
+		.etype	= KRB5_ENCTYPE_CAMELLIA128_CTS_CMAC,
+		.name	= "mic abc",
+		.plain	= "'abcdefghijk",
+		.K0	= "1DC46A8D763F4F93742BCBA3387576C3",
+		.usage	= 7,
+		.mic	= "1178E6C5C47A8C1AE0C4B9C7D4EB7B6B",
+	}, {
+		.etype	= KRB5_ENCTYPE_CAMELLIA128_CTS_CMAC,
+		.name	= "mic ABC",
+		.plain	= "'ABCDEFGHIJKLMNOPQRSTUVWXYZ",
+		.K0	= "5027BC231D0F3A9D23333F1CA6FDBE7C",
+		.usage	= 8,
+		.mic	= "D1B34F7004A731F23A0C00BF6C3F753A",
+	}, {
+		.etype	= KRB5_ENCTYPE_CAMELLIA256_CTS_CMAC,
+		.name	= "mic 123",
+		.plain	= "'123456789",
+		.K0	= "B61C86CC4E5D2757545AD423399FB7031ECAB913CBB900BD7A3C6DD8BF92015B",
+		.usage	= 9,
+		.mic	= "87A12CFD2B96214810F01C826E7744B1",
+	}, {
+		.etype	= KRB5_ENCTYPE_CAMELLIA256_CTS_CMAC,
+		.name	= "mic !@#",
+		.plain	= "'!@#$%^&*()!@#$%^&*()!@#$%^&*()",
+		.K0	= "32164C5B434D1D1538E4CFD9BE8040FE8C4AC7ACC4B93D3314D2133668147A05",
+		.usage	= 10,
+		.mic	= "3FA0B42355E52B189187294AA252AB64",
+	},
 	{/* END */}
 };
diff --git a/include/crypto/krb5.h b/include/crypto/krb5.h
index 6921785688bf..b337494ccb31 100644
--- a/include/crypto/krb5.h
+++ b/include/crypto/krb5.h
@@ -35,6 +35,8 @@ struct scatterlist;
 #define KRB5_ENCTYPE_AES256_CTS_HMAC_SHA384_192	0x0014
 #define KRB5_ENCTYPE_ARCFOUR_HMAC		0x0017
 #define KRB5_ENCTYPE_ARCFOUR_HMAC_EXP		0x0018
+#define KRB5_ENCTYPE_CAMELLIA128_CTS_CMAC	0x0019
+#define KRB5_ENCTYPE_CAMELLIA256_CTS_CMAC	0x001a
 #define KRB5_ENCTYPE_UNKNOWN			0x01ff
 
 #define KRB5_CKSUMTYPE_CRC32			0x0001
@@ -47,6 +49,8 @@ struct scatterlist;
 #define KRB5_CKSUMTYPE_HMAC_SHA1_DES3		0x000c
 #define KRB5_CKSUMTYPE_HMAC_SHA1_96_AES128	0x000f
 #define KRB5_CKSUMTYPE_HMAC_SHA1_96_AES256	0x0010
+#define KRB5_CKSUMTYPE_CMAC_CAMELLIA128		0x0011
+#define KRB5_CKSUMTYPE_CMAC_CAMELLIA256		0x0012
 #define KRB5_CKSUMTYPE_HMAC_SHA256_128_AES128	0x0013
 #define KRB5_CKSUMTYPE_HMAC_SHA384_192_AES256	0x0014
 #define KRB5_CKSUMTYPE_HMAC_MD5_ARCFOUR		-138 /* Microsoft md5 hmac cksumtype */

[RFC PATCH 20/24] rxrpc: Add the security index for yfs-rxgk

[David Howells]

Add the security index and abort codes for the YFS variant of rxgk.

Signed-off-by: David Howells <dhowells@redhat.com>
---
 fs/afs/misc.c              | 13 +++++++++++++
 include/uapi/linux/rxrpc.h | 17 +++++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/fs/afs/misc.c b/fs/afs/misc.c
index b8180bf2281f..57f779804d50 100644
--- a/fs/afs/misc.c
+++ b/fs/afs/misc.c
@@ -103,6 +103,19 @@ int afs_abort_to_error(u32 abort_code)
 	case RXKADDATALEN:	return -EKEYREJECTED;
 	case RXKADILLEGALLEVEL:	return -EKEYREJECTED;
 
+	case RXGK_INCONSISTENCY:	return -EPROTO;
+	case RXGK_PACKETSHORT:		return -EPROTO;
+	case RXGK_BADCHALLENGE:		return -EPROTO;
+	case RXGK_BADETYPE:		return -ENOPKG;
+	case RXGK_BADLEVEL:		return -EKEYREJECTED;
+	case RXGK_BADKEYNO:		return -EKEYREJECTED;
+	case RXGK_EXPIRED:		return -EKEYEXPIRED;
+	case RXGK_NOTAUTH:		return -EKEYREJECTED;
+	case RXGK_BAD_TOKEN:		return -EKEYREJECTED;
+	case RXGK_SEALED_INCON:		return -EKEYREJECTED;
+	case RXGK_DATA_LEN:		return -EPROTO;
+	case RXGK_BAD_QOP:		return -EKEYREJECTED;
+
 	case RXGEN_OPCODE:	return -ENOTSUPP;
 
 	default:		return -EREMOTEIO;
diff --git a/include/uapi/linux/rxrpc.h b/include/uapi/linux/rxrpc.h
index 8f8dc7a937a4..0e296d219191 100644
--- a/include/uapi/linux/rxrpc.h
+++ b/include/uapi/linux/rxrpc.h
@@ -73,6 +73,7 @@ enum rxrpc_cmsg_type {
 #define RXRPC_SECURITY_RXKAD	2	/* kaserver or kerberos 4 */
 #define RXRPC_SECURITY_RXGK	4	/* gssapi-based */
 #define RXRPC_SECURITY_RXK5	5	/* kerberos 5 */
+#define RXRPC_SECURITY_YFS_RXGK	6	/* YFS gssapi-based */
 
 /*
  * RxRPC-level abort codes
@@ -118,4 +119,20 @@ enum rxrpc_cmsg_type {
 #define RXKADDATALEN		19270411	/* user data too long */
 #define RXKADILLEGALLEVEL	19270412	/* caller not authorised to use encrypted conns */
 
+/*
+ * RxGK GSSAPI security abort codes.
+ */
+#define RXGK_INCONSISTENCY	1233242880	/* Security module structure inconsistent */
+#define RXGK_PACKETSHORT	1233242881	/* Packet too short for security challenge */
+#define RXGK_BADCHALLENGE	1233242882	/* Invalid security challenge */
+#define RXGK_BADETYPE		1233242883	/* Invalid or impermissible encryption type */
+#define RXGK_BADLEVEL		1233242884	/* Invalid or impermissible security level */
+#define RXGK_BADKEYNO		1233242885	/* Key version number not found */
+#define RXGK_EXPIRED		1233242886	/* Token has expired */
+#define RXGK_NOTAUTH		1233242887	/* Caller not authorized */
+#define RXGK_BAD_TOKEN		1233242888	/* Security object was passed a bad token */
+#define RXGK_SEALED_INCON	1233242889	/* Sealed data inconsistent */
+#define RXGK_DATA_LEN		1233242890	/* User data too long */
+#define RXGK_BAD_QOP		1233242891	/* Inadequate quality of protection available */
+
 #endif /* _UAPI_LINUX_RXRPC_H */

[RFC PATCH 21/24] rxrpc: Add YFS RxGK (GSSAPI) security class

[David Howells]

Add support for the YFS-variant RxGK security class to support
GSSAPI-derived authentication.  This also allows the use of better crypto
over the rxkad security class.

The key payload is XDR encoded of the form:

    typedef int64_t opr_time;

    const AFSTOKEN_RK_TIX_MAX = 12000; 	/* Matches entry in rxkad.h */

    struct token_rxkad {
	afs_int32 viceid;
	afs_int32 kvno;
	afs_int64 key;
	afs_int32 begintime;
	afs_int32 endtime;
	afs_int32 primary_flag;
	opaque ticket<AFSTOKEN_RK_TIX_MAX>;
    };

    struct token_rxgk {
	opr_time begintime;
	opr_time endtime;
	afs_int64 level;
	afs_int64 lifetime;
	afs_int64 bytelife;
	afs_int64 enctype;
	opaque key<>;
	opaque ticket<>;
    };

    const AFSTOKEN_UNION_NOAUTH = 0;
    const AFSTOKEN_UNION_KAD = 2;
    const AFSTOKEN_UNION_YFSGK = 6;

    union ktc_tokenUnion switch (afs_int32 type) {
	case AFSTOKEN_UNION_KAD:
	    token_rxkad kad;
	case AFSTOKEN_UNION_YFSGK:
	    token_rxgk  gk;
    };

    const AFSTOKEN_LENGTH_MAX = 16384;
    typedef opaque token_opaque<AFSTOKEN_LENGTH_MAX>;

    const AFSTOKEN_MAX = 8;
    const AFSTOKEN_CELL_MAX = 64;

    struct ktc_setTokenData {
	afs_int32 flags;
	string cell<AFSTOKEN_CELL_MAX>;
	token_opaque tokens<AFSTOKEN_MAX>;
    };

The parser for the basic token struct is already present, as is the rxkad
token type.  This adds a parser for the rxgk token type.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 include/keys/rxrpc-type.h |  17 ++++
 net/rxrpc/key.c           | 183 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 200 insertions(+)

diff --git a/include/keys/rxrpc-type.h b/include/keys/rxrpc-type.h
index 333c0f49a9cd..0ddbe197a261 100644
--- a/include/keys/rxrpc-type.h
+++ b/include/keys/rxrpc-type.h
@@ -9,6 +9,7 @@
 #define _KEYS_RXRPC_TYPE_H
 
 #include <linux/key.h>
+#include <crypto/krb5.h>
 
 /*
  * key type for AF_RXRPC keys
@@ -31,6 +32,21 @@ struct rxkad_key {
 	u8	ticket[];		/* the encrypted ticket */
 };
 
+/*
+ * RxRPC key for YFS-RxGK (type-6 security)
+ */
+struct rxgk_key {
+	s64		begintime;	/* Time at which the ticket starts */
+	s64		endtime;	/* Time at which the ticket ends */
+	u64		lifetime;	/* Maximum lifespan of a connection (seconds) */
+	u64		bytelife;	/* Maximum number of bytes on a connection */
+	unsigned int	enctype;	/* Encoding type */
+	s8		level;		/* Negotiated security RXRPC_SECURITY_PLAIN/AUTH/ENCRYPT */
+	struct krb5_buffer key;		/* Master key, K0 */
+	struct krb5_buffer ticket;	/* Ticket to be passed to server */
+	u8		_key[];		/* Key storage */
+};
+
 /*
  * list of tokens attached to an rxrpc key
  */
@@ -40,6 +56,7 @@ struct rxrpc_key_token {
 	struct rxrpc_key_token *next;	/* the next token in the list */
 	union {
 		struct rxkad_key *kad;
+		struct rxgk_key *rxgk;
 	};
 };
 
diff --git a/net/rxrpc/key.c b/net/rxrpc/key.c
index 33e8302a79e3..2e42a0bbeac2 100644
--- a/net/rxrpc/key.c
+++ b/net/rxrpc/key.c
@@ -129,6 +129,158 @@ static int rxrpc_preparse_xdr_rxkad(struct key_preparsed_payload *prep,
 	return 0;
 }
 
+static u64 xdr_dec64(const __be32 *xdr)
+{
+	return (u64)ntohl(xdr[0]) << 32 | (u64)ntohl(xdr[1]);
+}
+
+static time64_t rxrpc_s64_to_time64(s64 time_in_100ns)
+{
+	bool neg = false;
+	u64 tmp = time_in_100ns;
+
+	if (time_in_100ns < 0) {
+		tmp = -time_in_100ns;
+		neg = true;
+	}
+	do_div(tmp, 10000000);
+	return neg ? -tmp : tmp;
+}
+
+/*
+ * Parse a YFS-RxGK type XDR format token
+ * - the caller guarantees we have at least 4 words
+ *
+ * struct token_rxgk {
+ *	opr_time begintime;
+ *	opr_time endtime;
+ *	afs_int64 level;
+ *	afs_int64 lifetime;
+ *	afs_int64 bytelife;
+ *	afs_int64 enctype;
+ *	opaque key<>;
+ *	opaque ticket<>;
+ * };
+ */
+static int rxrpc_preparse_xdr_yfs_rxgk(struct key_preparsed_payload *prep,
+				       size_t datalen,
+				       const __be32 *xdr, unsigned int toklen)
+{
+	struct rxrpc_key_token *token, **pptoken;
+	time64_t expiry;
+	size_t plen;
+	const __be32 *ticket, *key;
+	s64 tmp;
+	u32 tktlen, keylen;
+
+	_enter(",{%x,%x,%x,%x},%x",
+	       ntohl(xdr[0]), ntohl(xdr[1]), ntohl(xdr[2]), ntohl(xdr[3]),
+	       toklen);
+
+	if (6 * 2 + 2 > toklen / 4)
+		goto reject;
+
+	key = xdr + (6 * 2 + 1);
+	keylen = ntohl(key[-1]);
+	_debug("keylen: %x", keylen);
+	keylen = round_up(keylen, 4);
+	if ((6 * 2 + 2) * 4 + keylen > toklen)
+		goto reject;
+
+	ticket = xdr + (6 * 2 + 1 + (keylen / 4) + 1);
+	tktlen = ntohl(ticket[-1]);
+	_debug("tktlen: %x", tktlen);
+	tktlen = round_up(tktlen, 4);
+	if ((6 * 2 + 2) * 4 + keylen + tktlen != toklen) {
+		kleave(" = -EKEYREJECTED [%x!=%x, %x,%x]",
+		       (6 * 2 + 2) * 4 + keylen + tktlen, toklen,
+		       keylen, tktlen);
+		goto reject;
+	}
+
+	plen = sizeof(*token) + sizeof(*token->rxgk) + tktlen + keylen;
+	prep->quotalen = datalen + plen;
+
+	plen -= sizeof(*token);
+	token = kzalloc(sizeof(*token), GFP_KERNEL);
+	if (!token)
+		goto nomem;
+
+	token->rxgk = kzalloc(sizeof(*token->rxgk) + keylen, GFP_KERNEL);
+	if (!token->rxgk)
+		goto nomem_token;
+
+	token->security_index	= RXRPC_SECURITY_YFS_RXGK;
+	token->rxgk->begintime	= xdr_dec64(xdr + 0 * 2);
+	token->rxgk->endtime	= xdr_dec64(xdr + 1 * 2);
+	token->rxgk->level	= tmp = xdr_dec64(xdr + 2 * 2);
+	if (tmp < -1LL || tmp > RXRPC_SECURITY_ENCRYPT)
+		goto reject_token;
+	token->rxgk->lifetime	= xdr_dec64(xdr + 3 * 2);
+	token->rxgk->bytelife	= xdr_dec64(xdr + 4 * 2);
+	token->rxgk->enctype	= tmp = xdr_dec64(xdr + 5 * 2);
+	if (tmp < 0 || tmp > UINT_MAX)
+		goto reject_token;
+	token->rxgk->key.len	= ntohl(key[-1]);
+	token->rxgk->key.data	= token->rxgk->_key;
+	token->rxgk->ticket.len = ntohl(ticket[-1]);
+
+	expiry = rxrpc_s64_to_time64(token->rxgk->endtime);
+	if (expiry < 0)
+		goto expired;
+	if (expiry < prep->expiry)
+		prep->expiry = expiry;
+
+	memcpy(token->rxgk->key.data, key, token->rxgk->key.len);
+
+	/* Pad the ticket so that we can use it directly in XDR */
+	token->rxgk->ticket.data = kzalloc(round_up(token->rxgk->ticket.len, 4),
+					   GFP_KERNEL);
+	if (!token->rxgk->ticket.data)
+		goto nomem_yrxgk;
+	memcpy(token->rxgk->ticket.data, ticket, token->rxgk->ticket.len);
+
+	_debug("SCIX: %u",	token->security_index);
+	_debug("EXPY: %llx",	token->rxgk->endtime);
+	_debug("LIFE: %llx",	token->rxgk->lifetime);
+	_debug("BYTE: %llx",	token->rxgk->bytelife);
+	_debug("ENC : %u",	token->rxgk->enctype);
+	_debug("LEVL: %u",	token->rxgk->level);
+	_debug("KLEN: %u",	token->rxgk->key.len);
+	_debug("TLEN: %u",	token->rxgk->ticket.len);
+	_debug("KEY0: %*phN",	token->rxgk->key.len, token->rxgk->key.data);
+	_debug("TICK: %*phN",
+	       min_t(u32, token->rxgk->ticket.len, 32), token->rxgk->ticket.data);
+
+	/* count the number of tokens attached */
+	prep->payload.data[1] = (void *)((unsigned long)prep->payload.data[1] + 1);
+
+	/* attach the data */
+	for (pptoken = (struct rxrpc_key_token **)&prep->payload.data[0];
+	     *pptoken;
+	     pptoken = &(*pptoken)->next)
+		continue;
+	*pptoken = token;
+
+	_leave(" = 0");
+	return 0;
+
+nomem_yrxgk:
+	kfree(token->rxgk);
+nomem_token:
+	kfree(token);
+nomem:
+	return -ENOMEM;
+reject_token:
+	kfree(token);
+reject:
+	return -EKEYREJECTED;
+expired:
+	kfree(token->rxgk);
+	kfree(token);
+	return -EKEYEXPIRED;
+}
+
 /*
  * attempt to parse the data as the XDR format
  * - the caller guarantees we have more than 7 words
@@ -228,6 +380,9 @@ static int rxrpc_preparse_xdr(struct key_preparsed_payload *prep)
 		case RXRPC_SECURITY_RXKAD:
 			ret2 = rxrpc_preparse_xdr_rxkad(prep, datalen, token, toklen);
 			break;
+		case RXRPC_SECURITY_YFS_RXGK:
+			ret2 = rxrpc_preparse_xdr_yfs_rxgk(prep, datalen, token, toklen);
+			break;
 		default:
 			ret2 = -EPROTONOSUPPORT;
 			break;
@@ -390,6 +545,10 @@ static void rxrpc_free_token_list(struct rxrpc_key_token *token)
 		case RXRPC_SECURITY_RXKAD:
 			kfree(token->kad);
 			break;
+		case RXRPC_SECURITY_YFS_RXGK:
+			kfree(token->rxgk->ticket.data);
+			kfree(token->rxgk);
+			break;
 		default:
 			pr_err("Unknown token type %x on rxrpc key\n",
 			       token->security_index);
@@ -433,6 +592,9 @@ static void rxrpc_describe(const struct key *key, struct seq_file *m)
 		case RXRPC_SECURITY_RXKAD:
 			seq_puts(m, "ka");
 			break;
+		case RXRPC_SECURITY_YFS_RXGK:
+			seq_puts(m, "ygk");
+			break;
 		default: /* we have a ticket we can't encode */
 			seq_printf(m, "%u", token->security_index);
 			break;
@@ -595,6 +757,13 @@ static long rxrpc_read(const struct key *key,
 				toksize += RND(token->kad->ticket_len);
 			break;
 
+		case RXRPC_SECURITY_YFS_RXGK:
+			toksize += 6 * 8 + 2 * 4;
+			if (!token->no_leak_key)
+				toksize += RND(token->rxgk->key.len);
+			toksize += RND(token->rxgk->ticket.len);
+			break;
+
 		default: /* we have a ticket we can't encode */
 			pr_err("Unsupported key token type (%u)\n",
 			       token->security_index);
@@ -674,6 +843,20 @@ static long rxrpc_read(const struct key *key,
 				ENCODE_DATA(token->kad->ticket_len, token->kad->ticket);
 			break;
 
+		case RXRPC_SECURITY_YFS_RXGK:
+			ENCODE64(token->rxgk->begintime);
+			ENCODE64(token->rxgk->endtime);
+			ENCODE64(token->rxgk->level);
+			ENCODE64(token->rxgk->lifetime);
+			ENCODE64(token->rxgk->bytelife);
+			ENCODE64(token->rxgk->enctype);
+			if (token->no_leak_key)
+				ENCODE(0);
+			else
+				ENCODE_DATA(token->rxgk->key.len, token->rxgk->key.data);
+			ENCODE_DATA(token->rxgk->ticket.len, token->rxgk->ticket.data);
+			break;
+
 		default:
 			pr_err("Unsupported key token type (%u)\n",
 			       token->security_index);

[RFC PATCH 22/24] rxrpc: rxgk: Provide infrastructure and key derivation

[David Howells]

Provide some infrastructure for implementing the RxGK transport security
class:

 (1) A definition of an encoding type, including:

	- Relevant crypto-layer names
	- Lengths of the crypto keys and checksums involved
	- Crypto functions specific to the encoding type
	- Crypto scheme used for that type

 (2) A definition of a crypto scheme, including:

	- Underlying crypto handlers
	- The pseudo-random function, PRF, used in base key derivation
	- Functions for deriving usage keys Kc, Ke and Ki
	- Functions for en/decrypting parts of an sk_buff

 (3) A key context, with the usage keys required for a derivative of a
     transport key for a specific key number.  This includes keys for
     securing packets for transmission, extracting received packets and
     dealing with response packets.

 (3) A function to look up an encoding type by number.

 (4) A function to set up a key context and derive the keys.

 (5) A function to set up the keys required to extract the ticket obtained
     from the GSS negotiation in the server.

 (6) Miscellaneous functions for context handling.

The keys and key derivation functions are described in:

	tools.ietf.org/html/draft-wilkinson-afs3-rxgk-11

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 net/rxrpc/Kconfig       |  10 ++
 net/rxrpc/Makefile      |   3 +-
 net/rxrpc/ar-internal.h |   3 +
 net/rxrpc/rxgk_common.h |  48 +++++++
 net/rxrpc/rxgk_kdf.c    | 287 ++++++++++++++++++++++++++++++++++++++++
 5 files changed, 350 insertions(+), 1 deletion(-)
 create mode 100644 net/rxrpc/rxgk_common.h
 create mode 100644 net/rxrpc/rxgk_kdf.c

diff --git a/net/rxrpc/Kconfig b/net/rxrpc/Kconfig
index a20986806fea..0a2b38b9b94a 100644
--- a/net/rxrpc/Kconfig
+++ b/net/rxrpc/Kconfig
@@ -67,6 +67,16 @@ config RXKAD
 
 	  See Documentation/networking/rxrpc.rst.
 
+config RXGK
+	bool "RxRPC GSSAPI security"
+	depends on AF_RXRPC
+	depends on CRYPTO_KRB5
+	help
+	  Provide the GSSAPI-based RxGK security class for AFS.  Keys are added
+	  with add_key().
+
+	  See Documentation/networking/rxrpc.rst.
+
 config RXPERF
 	tristate "RxRPC test service"
 	help
diff --git a/net/rxrpc/Makefile b/net/rxrpc/Makefile
index 210b75e3179e..9c8eb1471054 100644
--- a/net/rxrpc/Makefile
+++ b/net/rxrpc/Makefile
@@ -39,6 +39,7 @@ rxrpc-y := \
 rxrpc-$(CONFIG_PROC_FS) += proc.o
 rxrpc-$(CONFIG_RXKAD) += rxkad.o
 rxrpc-$(CONFIG_SYSCTL) += sysctl.o
-
+rxrpc-$(CONFIG_RXGK) += \
+	rxgk_kdf.o
 
 obj-$(CONFIG_RXPERF) += rxperf.o
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 718193df9d2e..2392f2e062c2 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -526,6 +526,9 @@ struct rxrpc_connection {
 			struct rxrpc_crypt csum_iv;	/* packet checksum base */
 			u32	nonce;		/* response re-use preventer */
 		} rxkad;
+		struct {
+			u64	start_time;	/* The start time for TK derivation */
+		} rxgk;
 	};
 	unsigned long		flags;
 	unsigned long		events;
diff --git a/net/rxrpc/rxgk_common.h b/net/rxrpc/rxgk_common.h
new file mode 100644
index 000000000000..c07a5386b303
--- /dev/null
+++ b/net/rxrpc/rxgk_common.h
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* Common bits for GSSAPI-based RxRPC security.
+ *
+ * Copyright (C) 2023 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#include <crypto/krb5.h>
+#include <crypto/skcipher.h>
+#include <crypto/hash.h>
+
+/*
+ * Per-key number context.  This is replaced when the connection is rekeyed.
+ */
+struct rxgk_context {
+	refcount_t		usage;
+	unsigned int		key_number;	/* Rekeying number (goes in the rx header) */
+	unsigned long		flags;
+#define RXGK_TK_NEEDS_REKEY	0		/* Set if this needs rekeying */
+	unsigned long		expiry;		/* Expiration time of this key */
+	long long		bytes_remaining; /* Remaining Tx lifetime of this key */
+	const struct krb5_enctype *krb5;	/* RxGK encryption type */
+	const struct rxgk_key	*key;
+
+	/* We need up to 7 keys derived from the transport key, but we don't
+	 * actually need the transport key.  Each key is derived by
+	 * DK(TK,constant).
+	 */
+	struct crypto_aead	*tx_enc;	/* Transmission key */
+	struct crypto_aead	*rx_enc;	/* Reception key */
+	struct crypto_shash	*tx_Kc;		/* Transmission checksum key */
+	struct crypto_shash	*rx_Kc;		/* Reception checksum key */
+	struct crypto_aead	*resp_enc;	/* Response packet enc key */
+};
+
+/*
+ * rxgk_kdf.c
+ */
+void rxgk_put(struct rxgk_context *gk);
+struct rxgk_context *rxgk_generate_transport_key(struct rxrpc_connection *conn,
+						 const struct rxgk_key *key,
+						 unsigned int key_number,
+						 gfp_t gfp);
+int rxgk_set_up_token_cipher(const struct krb5_buffer *server_key,
+			     struct crypto_aead **token_key,
+			     unsigned int enctype,
+			     const struct krb5_enctype **_krb5,
+			     gfp_t gfp);
diff --git a/net/rxrpc/rxgk_kdf.c b/net/rxrpc/rxgk_kdf.c
new file mode 100644
index 000000000000..ef0e57e5a6df
--- /dev/null
+++ b/net/rxrpc/rxgk_kdf.c
@@ -0,0 +1,287 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* RxGK transport key derivation.
+ *
+ * Copyright (C) 2023 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/key-type.h>
+#include <linux/slab.h>
+#include <keys/rxrpc-type.h>
+#include "ar-internal.h"
+#include "rxgk_common.h"
+
+#define round16(x) (((x) + 15) & ~15)
+
+/*
+ * Constants used to derive the keys and hmacs actually used for doing stuff.
+ */
+#define RXGK_CLIENT_ENC_PACKET		1026U // 0x402
+#define RXGK_CLIENT_MIC_PACKET          1027U // 0x403
+#define RXGK_SERVER_ENC_PACKET          1028U // 0x404
+#define RXGK_SERVER_MIC_PACKET          1029U // 0x405
+#define RXGK_CLIENT_ENC_RESPONSE        1030U // 0x406
+#define RXGK_SERVER_ENC_TOKEN           1036U // 0x40c
+
+static void rxgk_free(struct rxgk_context *gk)
+{
+	if (gk->tx_Kc)
+		crypto_free_shash(gk->tx_Kc);
+	if (gk->rx_Kc)
+		crypto_free_shash(gk->rx_Kc);
+	if (gk->tx_enc)
+		crypto_free_aead(gk->tx_enc);
+	if (gk->rx_enc)
+		crypto_free_aead(gk->rx_enc);
+	if (gk->resp_enc)
+		crypto_free_aead(gk->resp_enc);
+	kfree(gk);
+}
+
+void rxgk_put(struct rxgk_context *gk)
+{
+	if (gk && refcount_dec_and_test(&gk->usage))
+		rxgk_free(gk);
+}
+
+/*
+ * Transport key derivation function.
+ *
+ *      TK = random-to-key(PRF+(K0, L,
+ *                         epoch || cid || start_time || key_number))
+ *      [tools.ietf.org/html/draft-wilkinson-afs3-rxgk-11 sec 8.3]
+ */
+static int rxgk_derive_transport_key(struct rxrpc_connection *conn,
+				     struct rxgk_context *gk,
+				     const struct rxgk_key *rxgk,
+				     struct krb5_buffer *TK,
+				     gfp_t gfp)
+{
+	const struct krb5_enctype *krb5 = gk->krb5;
+	struct krb5_buffer conn_info;
+	unsigned int L = krb5->key_bytes;
+	__be32 *info;
+	u8 *buffer;
+	int ret;
+
+	_enter("");
+
+	conn_info.len = sizeof(__be32) * 5;
+
+	buffer = kzalloc(round16(conn_info.len), gfp);
+	if (!buffer)
+		return -ENOMEM;
+
+	conn_info.data = buffer;
+
+	info = (__be32 *)conn_info.data;
+	info[0] = htonl(conn->proto.epoch);
+	info[1] = htonl(conn->proto.cid);
+	info[2] = htonl(conn->rxgk.start_time >> 32);
+	info[3] = htonl(conn->rxgk.start_time >>  0);
+	info[4] = htonl(gk->key_number);
+
+	ret = crypto_krb5_calc_PRFplus(krb5, &rxgk->key, L, &conn_info, TK, gfp);
+	kfree_sensitive(buffer);
+	_leave(" = %d", ret);
+	return ret;
+}
+
+/*
+ * Set up the ciphers for the usage keys.
+ */
+static int rxgk_set_up_ciphers(struct rxrpc_connection *conn,
+			       struct rxgk_context *gk,
+			       const struct rxgk_key *rxgk,
+			       gfp_t gfp)
+{
+	const struct krb5_enctype *krb5 = gk->krb5;
+	struct crypto_shash *shash;
+	struct crypto_aead *aead;
+	struct krb5_buffer TK;
+	bool service = rxrpc_conn_is_service(conn);
+	int ret;
+	u8 *buffer;
+
+	buffer = kzalloc(krb5->key_bytes, gfp);
+	if (!buffer)
+		return -ENOMEM;
+
+	TK.len = krb5->key_bytes;
+	TK.data = buffer;
+
+	ret = rxgk_derive_transport_key(conn, gk, rxgk, &TK, gfp);
+	if (ret < 0)
+		goto out;
+
+	aead = crypto_krb5_prepare_encryption(krb5, &TK, RXGK_CLIENT_ENC_RESPONSE, gfp);
+	if (IS_ERR(aead))
+		goto aead_error;
+	gk->resp_enc = aead;
+
+	if (crypto_aead_blocksize(gk->resp_enc) != krb5->block_len ||
+	    crypto_aead_authsize(gk->resp_enc) != krb5->cksum_len) {
+		pr_notice("algo inconsistent with krb5 table %u!=%u or %u!=%u\n",
+			  crypto_aead_blocksize(gk->resp_enc), krb5->block_len,
+			  crypto_aead_authsize(gk->resp_enc), krb5->cksum_len);
+		return -EINVAL;
+	}
+
+	if (service) {
+		switch (conn->security_level) {
+		case RXRPC_SECURITY_AUTH:
+			shash = crypto_krb5_prepare_checksum(
+				krb5, &TK, RXGK_SERVER_MIC_PACKET, gfp);
+			if (IS_ERR(shash))
+				goto hash_error;
+			gk->tx_Kc = shash;
+			shash = crypto_krb5_prepare_checksum(
+				krb5, &TK, RXGK_CLIENT_MIC_PACKET, gfp);
+			if (IS_ERR(shash))
+				goto hash_error;
+			gk->rx_Kc = shash;
+			break;
+		case RXRPC_SECURITY_ENCRYPT:
+			aead = crypto_krb5_prepare_encryption(
+				krb5, &TK, RXGK_SERVER_ENC_PACKET, gfp);
+			if (IS_ERR(aead))
+				goto aead_error;
+			gk->tx_enc = aead;
+			aead = crypto_krb5_prepare_encryption(
+				krb5, &TK, RXGK_CLIENT_ENC_PACKET, gfp);
+			if (IS_ERR(aead))
+				goto aead_error;
+			gk->rx_enc = aead;
+			break;
+		}
+	} else {
+		switch (conn->security_level) {
+		case RXRPC_SECURITY_AUTH:
+			shash = crypto_krb5_prepare_checksum(
+				krb5, &TK, RXGK_CLIENT_MIC_PACKET, gfp);
+			if (IS_ERR(shash))
+				goto hash_error;
+			gk->tx_Kc = shash;
+			shash = crypto_krb5_prepare_checksum(
+				krb5, &TK, RXGK_SERVER_MIC_PACKET, gfp);
+			if (IS_ERR(shash))
+				goto hash_error;
+			gk->rx_Kc = shash;
+			break;
+		case RXRPC_SECURITY_ENCRYPT:
+			aead = crypto_krb5_prepare_encryption(
+				krb5, &TK, RXGK_CLIENT_ENC_PACKET, gfp);
+			if (IS_ERR(aead))
+				goto aead_error;
+			gk->tx_enc = aead;
+			aead = crypto_krb5_prepare_encryption(
+				krb5, &TK, RXGK_SERVER_ENC_PACKET, gfp);
+			if (IS_ERR(aead))
+				goto aead_error;
+			gk->rx_enc = aead;
+			break;
+		}
+	}
+
+	ret = 0;
+out:
+	kfree_sensitive(buffer);
+	return ret;
+aead_error:
+	ret = PTR_ERR(aead);
+	goto out;
+hash_error:
+	ret = PTR_ERR(shash);
+	goto out;
+}
+
+/*
+ * Derive a transport key for a connection and then derive a bunch of usage
+ * keys from it and set up ciphers using them.
+ */
+struct rxgk_context *rxgk_generate_transport_key(struct rxrpc_connection *conn,
+						 const struct rxgk_key *key,
+						 unsigned int key_number,
+						 gfp_t gfp)
+{
+	struct rxgk_context *gk;
+	unsigned long lifetime;
+	int ret = -ENOPKG;
+
+	_enter("");
+
+	gk = kzalloc(sizeof(*gk), GFP_KERNEL);
+	if (!gk)
+		return ERR_PTR(-ENOMEM);
+	refcount_set(&gk->usage, 1);
+	gk->key		= key;
+	gk->key_number	= key_number;
+
+	gk->krb5 = crypto_krb5_find_enctype(key->enctype);
+	if (!gk->krb5)
+		goto err_tk;
+
+	ret = rxgk_set_up_ciphers(conn, gk, key, gfp);
+	if (ret)
+		goto err_tk;
+
+	/* Set the remaining number of bytes encrypted with this key that may
+	 * be transmitted before rekeying.  Note that the spec has been
+	 * interpreted differently on this point...
+	 */
+	switch (key->bytelife) {
+	case 0:
+	case 63:
+		gk->bytes_remaining = LLONG_MAX;
+		break;
+	case 1 ... 62:
+		gk->bytes_remaining = 1LL << key->bytelife;
+		break;
+	default:
+		gk->bytes_remaining = key->bytelife;
+		break;
+	}
+
+	/* Set the time after which rekeying must occur */
+	if (key->lifetime) {
+		lifetime = min_t(u64, key->lifetime, INT_MAX / HZ);
+		lifetime *= HZ;
+	} else {
+		lifetime = MAX_JIFFY_OFFSET;
+	}
+	gk->expiry = jiffies + lifetime;
+	return gk;
+
+err_tk:
+	rxgk_put(gk);
+	_leave(" = %d", ret);
+	return ERR_PTR(ret);
+}
+
+/*
+ * Use the server secret key to set up the ciphers that will be used to extract
+ * the token from a response packet.
+ */
+int rxgk_set_up_token_cipher(const struct krb5_buffer *server_key,
+			     struct crypto_aead **token_aead,
+			     unsigned int enctype,
+			     const struct krb5_enctype **_krb5,
+			     gfp_t gfp)
+{
+	const struct krb5_enctype *krb5;
+	struct crypto_aead *aead;
+
+	krb5 = crypto_krb5_find_enctype(enctype);
+	if (!krb5)
+		return -ENOPKG;
+
+	aead = crypto_krb5_prepare_encryption(krb5, server_key, RXGK_SERVER_ENC_TOKEN, gfp);
+	if (IS_ERR(aead))
+		return PTR_ERR(aead);
+
+	*_krb5 = krb5;
+	*token_aead = aead;
+	return 0;
+}

[RFC PATCH 23/24] rxrpc: rxgk: Implement the yfs-rxgk security class (GSSAPI)

[David Howells]

Implement the basic parts of the yfs-rxgk security class (security index 6)
to support GSSAPI-negotiated security.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 include/trace/events/rxrpc.h |   36 ++
 net/rxrpc/Makefile           |    2 +
 net/rxrpc/ar-internal.h      |   16 +
 net/rxrpc/conn_event.c       |    2 +-
 net/rxrpc/output.c           |    2 +-
 net/rxrpc/protocol.h         |   20 +
 net/rxrpc/rxgk.c             | 1026 ++++++++++++++++++++++++++++++++++
 net/rxrpc/rxgk_app.c         |  284 ++++++++++
 net/rxrpc/rxgk_common.h      |   92 +++
 net/rxrpc/rxkad.c            |    6 +-
 net/rxrpc/security.c         |    3 +
 11 files changed, 1485 insertions(+), 4 deletions(-)
 create mode 100644 net/rxrpc/rxgk.c
 create mode 100644 net/rxrpc/rxgk_app.c

diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h
index 2f119d18a061..168f3ab7c0e4 100644
--- a/include/trace/events/rxrpc.h
+++ b/include/trace/events/rxrpc.h
@@ -68,6 +68,38 @@
 	EM(rxkad_abort_resp_tkt_sname,		"rxkad-resp-tk-sname")	\
 	EM(rxkad_abort_resp_unknown_tkt,	"rxkad-resp-unknown-tkt") \
 	EM(rxkad_abort_resp_version,		"rxkad-resp-version")	\
+	/* RxGK security errors */					\
+	EM(rxgk_abort_1_verify_mic_eproto,	"rxgk1-vfy-mic-eproto")	\
+	EM(rxgk_abort_2_decrypt_eproto,		"rxgk2-dec-eproto")	\
+	EM(rxgk_abort_2_short_data,		"rxgk2-short-data")	\
+	EM(rxgk_abort_2_short_encdata,		"rxgk2-short-encdata")	\
+	EM(rxgk_abort_2_short_header,		"rxgk2-short-hdr")	\
+	EM(rxgk_abort_bad_key_number,		"rxgk-bad-key-num")	\
+	EM(rxgk_abort_chall_key_expired,	"rxgk-chall-key-exp")	\
+	EM(rxgk_abort_chall_no_key,		"rxgk-chall-nokey")	\
+	EM(rxgk_abort_chall_short,		"rxgk-chall-short")	\
+	EM(rxgk_abort_resp_auth_dec,		"rxgk-resp-auth-dec")	\
+	EM(rxgk_abort_resp_bad_callid,		"rxgk-resp-bad-callid")	\
+	EM(rxgk_abort_resp_bad_nonce,		"rxgk-resp-bad-nonce")	\
+	EM(rxgk_abort_resp_bad_param,		"rxgk-resp-bad-param")	\
+	EM(rxgk_abort_resp_call_ctr,		"rxgk-resp-call-ctr")	\
+	EM(rxgk_abort_resp_call_state,		"rxgk-resp-call-state")	\
+	EM(rxgk_abort_resp_internal_error,	"rxgk-resp-int-error")	\
+	EM(rxgk_abort_resp_nopkg,		"rxgk-resp-nopkg")	\
+	EM(rxgk_abort_resp_short_applen,	"rxgk-resp-short-applen") \
+	EM(rxgk_abort_resp_short_auth,		"rxgk-resp-short-auth") \
+	EM(rxgk_abort_resp_short_call_list,	"rxgk-resp-short-callls") \
+	EM(rxgk_abort_resp_short_packet,	"rxgk-resp-short-packet") \
+	EM(rxgk_abort_resp_short_yfs_klen,	"rxgk-resp-short-yfs-klen") \
+	EM(rxgk_abort_resp_short_yfs_key,	"rxgk-resp-short-yfs-key") \
+	EM(rxgk_abort_resp_short_yfs_tkt,	"rxgk-resp-short-yfs-tkt") \
+	EM(rxgk_abort_resp_tok_dec,		"rxgk-resp-tok-dec")	\
+	EM(rxgk_abort_resp_tok_internal_error,	"rxgk-resp-tok-int-err") \
+	EM(rxgk_abort_resp_tok_keyerr,		"rxgk-resp-tok-keyerr")	\
+	EM(rxgk_abort_resp_tok_nokey,		"rxgk-resp-tok-nokey")	\
+	EM(rxgk_abort_resp_tok_nopkg,		"rxgk-resp-tok-nopkg")	\
+	EM(rxgk_abort_resp_tok_short,		"rxgk-resp-tok-short")	\
+	EM(rxgk_abort_resp_xdr_align,		"rxgk-resp-xdr-align")	\
 	/* rxrpc errors */						\
 	EM(rxrpc_abort_call_improper_term,	"call-improper-term")	\
 	EM(rxrpc_abort_call_reset,		"call-reset")		\
@@ -454,6 +486,8 @@
 	EM(rxrpc_tx_point_call_final_resend,	"CallFinalResend") \
 	EM(rxrpc_tx_point_conn_abort,		"ConnAbort") \
 	EM(rxrpc_tx_point_reject,		"Reject") \
+	EM(rxrpc_tx_point_rxgk_challenge,	"RxGKChall") \
+	EM(rxrpc_tx_point_rxgk_response,	"RxGKResp") \
 	EM(rxrpc_tx_point_rxkad_challenge,	"RxkadChall") \
 	EM(rxrpc_tx_point_rxkad_response,	"RxkadResp") \
 	EM(rxrpc_tx_point_version_keepalive,	"VerKeepalive") \
@@ -472,6 +506,7 @@
 
 #define rxrpc_txbuf_traces \
 	EM(rxrpc_txbuf_alloc_data,		"ALLOC DATA ")	\
+	EM(rxrpc_txbuf_alloc_response,		"ALLOC RESP ")	\
 	EM(rxrpc_txbuf_free,			"FREE       ")	\
 	EM(rxrpc_txbuf_get_buffer,		"GET BUFFER ")	\
 	EM(rxrpc_txbuf_get_trans,		"GET TRANS  ")	\
@@ -479,6 +514,7 @@
 	EM(rxrpc_txbuf_put_cleaned,		"PUT CLEANED")	\
 	EM(rxrpc_txbuf_put_nomem,		"PUT NOMEM  ")	\
 	EM(rxrpc_txbuf_put_rotated,		"PUT ROTATED")	\
+	EM(rxrpc_txbuf_put_response_tx,		"PUT RESP TX")	\
 	EM(rxrpc_txbuf_put_send_aborted,	"PUT SEND-X ")	\
 	EM(rxrpc_txbuf_put_trans,		"PUT TRANS  ")	\
 	EM(rxrpc_txbuf_see_lost,		"SEE LOST   ")	\
diff --git a/net/rxrpc/Makefile b/net/rxrpc/Makefile
index 9c8eb1471054..2ef05701d6d1 100644
--- a/net/rxrpc/Makefile
+++ b/net/rxrpc/Makefile
@@ -40,6 +40,8 @@ rxrpc-$(CONFIG_PROC_FS) += proc.o
 rxrpc-$(CONFIG_RXKAD) += rxkad.o
 rxrpc-$(CONFIG_SYSCTL) += sysctl.o
 rxrpc-$(CONFIG_RXGK) += \
+	rxgk.o \
+	rxgk_app.o \
 	rxgk_kdf.o
 
 obj-$(CONFIG_RXPERF) += rxperf.o
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 2392f2e062c2..736dc6ea20ac 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -31,6 +31,7 @@ struct key_preparsed_payload;
 struct rxrpc_connection;
 struct rxrpc_txbuf;
 struct rxrpc_txqueue;
+struct rxgk_context;
 
 /*
  * Mark applied to socket buffers in skb->mark.  skb->priority is used
@@ -280,6 +281,11 @@ struct rxrpc_security {
 
 	/* clear connection security */
 	void (*clear)(struct rxrpc_connection *);
+
+	/* Default ticket -> key decoder */
+	int (*default_decode_ticket)(struct rxrpc_connection *conn, struct sk_buff *skb,
+				     unsigned int ticket_offset, unsigned int ticket_len,
+				     struct key **_key);
 };
 
 /*
@@ -527,7 +533,9 @@ struct rxrpc_connection {
 			u32	nonce;		/* response re-use preventer */
 		} rxkad;
 		struct {
+			struct rxgk_context *keys[1];
 			u64	start_time;	/* The start time for TK derivation */
+			u8	nonce[20];	/* Response re-use preventer */
 		} rxgk;
 	};
 	unsigned long		flags;
@@ -870,6 +878,8 @@ struct rxrpc_txbuf {
 	unsigned short		len;		/* Amount of data in buffer */
 	unsigned short		space;		/* Remaining data space */
 	unsigned short		offset;		/* Offset of fill point */
+	unsigned short		crypto_header;	/* Size of crypto header */
+	unsigned short		sec_header;	/* Size of security header */
 	unsigned short		pkt_len;	/* Size of packet content */
 	unsigned short		alloc_size;	/* Amount of bufferage allocated */
 	unsigned int		flags;
@@ -1295,6 +1305,7 @@ static inline struct rxrpc_net *rxrpc_net(struct net *net)
 /*
  * output.c
  */
+ssize_t do_udp_sendmsg(struct socket *socket, struct msghdr *msg, size_t len);
 void rxrpc_send_ACK(struct rxrpc_call *call, u8 ack_reason,
 		    rxrpc_serial_t serial, enum rxrpc_propose_ack_trace why);
 void rxrpc_send_probe_for_pmtud(struct rxrpc_call *call);
@@ -1366,6 +1377,11 @@ void rxrpc_call_add_rtt(struct rxrpc_call *call, enum rxrpc_rtt_rx_trace why,
 ktime_t rxrpc_get_rto_backoff(struct rxrpc_call *call, bool retrans);
 void rxrpc_call_init_rtt(struct rxrpc_call *call);
 
+/*
+ * rxgk.c
+ */
+extern const struct rxrpc_security rxgk_yfs;
+
 /*
  * rxkad.c
  */
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index 713e04394ceb..3c1663318626 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -57,7 +57,7 @@ int rxrpc_abort_conn(struct rxrpc_connection *conn, struct sk_buff *skb,
 				  sp->hdr.seq, abort_code, err);
 		rxrpc_poke_conn(conn, rxrpc_conn_get_poke_abort);
 	}
-	return -EPROTO;
+	return err;
 }
 
 /*
diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index 6f7a125d6e90..6e2def0d8773 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -18,7 +18,7 @@
 
 extern int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len);
 
-static ssize_t do_udp_sendmsg(struct socket *socket, struct msghdr *msg, size_t len)
+ssize_t do_udp_sendmsg(struct socket *socket, struct msghdr *msg, size_t len)
 {
 	struct sockaddr *sa = msg->msg_name;
 	struct sock *sk = socket->sk;
diff --git a/net/rxrpc/protocol.h b/net/rxrpc/protocol.h
index 42f70e4636f8..f8bfec12bc7e 100644
--- a/net/rxrpc/protocol.h
+++ b/net/rxrpc/protocol.h
@@ -181,4 +181,24 @@ struct rxkad_response {
 	__be32		ticket_len;	/* Kerberos ticket length  */
 } __packed;
 
+/*
+ * GSSAPI security type-4 and type-6 data header.
+ */
+struct rxgk_header {
+	__be32	epoch;
+	__be32	cid;
+	__be32	call_number;
+	__be32	seq;
+	__be32	sec_index;
+	__be32	data_len;
+} __packed;
+
+/*
+ * GSSAPI security type-4 and type-6 response packet header.
+ */
+struct rxgk_response {
+	__be64	start_time;
+	__be32	token_len;
+} __packed;
+
 #endif /* _LINUX_RXRPC_PACKET_H */
diff --git a/net/rxrpc/rxgk.c b/net/rxrpc/rxgk.c
new file mode 100644
index 000000000000..9c5c616c40cb
--- /dev/null
+++ b/net/rxrpc/rxgk.c
@@ -0,0 +1,1026 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* GSSAPI-based RxRPC security
+ *
+ * Copyright (C) 2023 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/net.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/key-type.h>
+#include "ar-internal.h"
+#include "rxgk_common.h"
+
+/*
+ * Parse the information from a server key
+ */
+static int rxgk_preparse_server_key(struct key_preparsed_payload *prep)
+{
+	const struct krb5_enctype *krb5;
+	struct krb5_buffer *server_key = (void *)&prep->payload.data[2];
+	unsigned int service, sec_class, kvno, enctype;
+	int n = 0;
+
+	_enter("%zu", prep->datalen);
+
+	if (sscanf(prep->orig_description, "%u:%u:%u:%u%n",
+		   &service, &sec_class, &kvno, &enctype, &n) != 4)
+		return -EINVAL;
+
+	if (prep->orig_description[n])
+		return -EINVAL;
+
+	krb5 = crypto_krb5_find_enctype(enctype);
+	if (!krb5)
+		return -ENOPKG;
+
+	prep->payload.data[0] = (struct krb5_enctype *)krb5;
+
+	if (prep->datalen != krb5->key_len)
+		return -EKEYREJECTED;
+
+	server_key->len = prep->datalen;
+	server_key->data = kmemdup(prep->data, prep->datalen, GFP_KERNEL);
+	if (!server_key->data)
+		return -ENOMEM;
+
+	_leave(" = 0");
+	return 0;
+}
+
+static void rxgk_free_server_key(union key_payload *payload)
+{
+	struct krb5_buffer *server_key = (void *)&payload->data[2];
+
+	kfree_sensitive(server_key->data);
+}
+
+static void rxgk_free_preparse_server_key(struct key_preparsed_payload *prep)
+{
+	rxgk_free_server_key(&prep->payload);
+}
+
+static void rxgk_destroy_server_key(struct key *key)
+{
+	rxgk_free_server_key(&key->payload);
+}
+
+static void rxgk_describe_server_key(const struct key *key, struct seq_file *m)
+{
+	const struct krb5_enctype *krb5 = key->payload.data[0];
+
+	if (krb5)
+		seq_printf(m, ": %s", krb5->name);
+}
+
+static struct rxgk_context *rxgk_get_key(struct rxrpc_connection *conn,
+					 u16 *specific_key_number)
+{
+	refcount_inc(&conn->rxgk.keys[0]->usage);
+	return conn->rxgk.keys[0];
+}
+
+/*
+ * initialise connection security
+ */
+static int rxgk_init_connection_security(struct rxrpc_connection *conn,
+					 struct rxrpc_key_token *token)
+{
+	struct rxgk_context *gk;
+	int ret;
+
+	_enter("{%d},{%x}", conn->debug_id, key_serial(conn->key));
+
+	conn->security_ix = token->security_index;
+	conn->security_level = token->rxgk->level;
+
+	if (rxrpc_conn_is_client(conn)) {
+		conn->rxgk.start_time = ktime_get();
+		do_div(conn->rxgk.start_time, 100);
+	}
+
+	gk = rxgk_generate_transport_key(conn, token->rxgk, 0, GFP_NOFS);
+	if (IS_ERR(gk))
+		return PTR_ERR(gk);
+	conn->rxgk.keys[0] = gk;
+
+	switch (conn->security_level) {
+	case RXRPC_SECURITY_PLAIN:
+	case RXRPC_SECURITY_AUTH:
+	case RXRPC_SECURITY_ENCRYPT:
+		break;
+	default:
+		ret = -EKEYREJECTED;
+		goto error;
+	}
+
+	ret = 0;
+error:
+	_leave(" = %d", ret);
+	return ret;
+}
+
+/*
+ * Clean up the crypto on a call.
+ */
+static void rxgk_free_call_crypto(struct rxrpc_call *call)
+{
+}
+
+/*
+ * Work out how much data we can put in a packet.
+ */
+static struct rxrpc_txbuf *rxgk_alloc_txbuf(struct rxrpc_call *call, size_t remain, gfp_t gfp)
+{
+	enum krb5_crypto_mode mode;
+	struct rxgk_context *gk;
+	struct rxrpc_txbuf *txb;
+	size_t shdr, alloc, limit, part, offset, gap;
+
+	switch (call->conn->security_level) {
+	default:
+		alloc = umin(remain, RXRPC_JUMBO_DATALEN);
+		return rxrpc_alloc_data_txbuf(call, alloc, 1, gfp);
+	case RXRPC_SECURITY_AUTH:
+		shdr = 0;
+		mode = KRB5_CHECKSUM_MODE;
+		break;
+	case RXRPC_SECURITY_ENCRYPT:
+		shdr = sizeof(struct rxgk_header);
+		mode = KRB5_ENCRYPT_MODE;
+		break;
+	}
+
+	gk = rxgk_get_key(call->conn, NULL);
+	if (IS_ERR(gk))
+		return NULL;
+
+	/* Work out the maximum amount of data that will fit. */
+	alloc = RXRPC_JUMBO_DATALEN;
+	limit = crypto_krb5_how_much_data(gk->krb5, mode, &alloc, &offset);
+
+	if (remain < limit - shdr) {
+		part = remain;
+		alloc = crypto_krb5_how_much_buffer(gk->krb5, mode,
+						    shdr + part, &offset);
+		gap = 0;
+	} else {
+		part = limit - shdr;
+		gap = RXRPC_JUMBO_DATALEN - alloc;
+		alloc = RXRPC_JUMBO_DATALEN;
+	}
+
+	rxgk_put(gk);
+
+	txb = rxrpc_alloc_data_txbuf(call, alloc, 16, gfp);
+	if (!txb)
+		return NULL;
+
+	txb->crypto_header	= offset;
+	txb->sec_header		= shdr;
+	txb->offset		+= offset + shdr;
+	txb->space		= part;
+
+	/* Clear excess space in the packet */
+	if (gap) {
+		struct rxrpc_wire_header *whdr = txb->kvec[0].iov_base;
+		void *p = whdr + 1;
+
+		memset(p + alloc - gap, 0, gap);
+	}
+	return txb;
+}
+
+/*
+ * Integrity mode (sign a packet - level 1 security)
+ */
+static int rxgk_secure_packet_integrity(const struct rxrpc_call *call,
+					struct rxgk_context *gk,
+					struct rxrpc_txbuf *txb)
+{
+	struct rxrpc_wire_header *whdr = txb->kvec[0].iov_base;
+	struct rxgk_header *hdr;
+	struct scatterlist sg[1];
+	struct krb5_buffer metadata;
+	void *payload = whdr + 1;
+	int ret = -ENOMEM;
+
+	_enter("");
+
+	hdr = kzalloc(sizeof(*hdr), GFP_NOFS);
+	if (!hdr)
+		goto error_gk;
+
+	hdr->epoch	= htonl(call->conn->proto.epoch);
+	hdr->cid	= htonl(call->cid);
+	hdr->call_number = htonl(call->call_id);
+	hdr->seq	= htonl(txb->seq);
+	hdr->sec_index	= htonl(call->security_ix);
+	hdr->data_len	= htonl(txb->len);
+	metadata.len = sizeof(*hdr);
+	metadata.data = hdr;
+
+	sg_init_table(sg, 1);
+	sg_set_buf(&sg[0], payload, txb->alloc_size);
+
+	ret = crypto_krb5_get_mic(gk->krb5, gk->tx_Kc, &metadata,
+				  sg, 1, txb->alloc_size,
+				  txb->crypto_header, txb->sec_header + txb->len);
+	if (ret >= 0) {
+		txb->pkt_len = ret;
+		if (txb->alloc_size == RXRPC_JUMBO_DATALEN)
+			txb->jumboable = true;
+		gk->bytes_remaining -= ret;
+	}
+	kfree(hdr);
+error_gk:
+	rxgk_put(gk);
+	_leave(" = %d", ret);
+	return ret;
+}
+
+/*
+ * wholly encrypt a packet (level 2 security)
+ */
+static int rxgk_secure_packet_encrypted(const struct rxrpc_call *call,
+					struct rxgk_context *gk,
+					struct rxrpc_txbuf *txb)
+{
+	struct rxrpc_wire_header *whdr = txb->kvec[0].iov_base;
+	struct rxgk_header *hdr;
+	struct scatterlist sg[1];
+	void *payload = whdr + 1;
+	int ret;
+
+	_enter("%x", txb->len);
+
+	/* Insert the header into the buffer. */
+	hdr = payload + txb->crypto_header;
+	hdr->epoch	 = htonl(call->conn->proto.epoch);
+	hdr->cid	 = htonl(call->cid);
+	hdr->call_number = htonl(call->call_id);
+	hdr->seq	 = htonl(txb->seq);
+	hdr->sec_index	 = htonl(call->security_ix);
+	hdr->data_len	 = htonl(txb->len);
+
+	sg_init_table(sg, 1);
+	sg_set_buf(&sg[0], payload, txb->alloc_size);
+
+	ret = crypto_krb5_encrypt(gk->krb5, gk->tx_enc,
+				  sg, 1, txb->alloc_size,
+				  txb->crypto_header, txb->sec_header + txb->len,
+				  false);
+	if (ret >= 0) {
+		txb->pkt_len = ret;
+		if (txb->alloc_size == RXRPC_JUMBO_DATALEN)
+			txb->jumboable = true;
+		gk->bytes_remaining -= ret;
+	}
+
+	rxgk_put(gk);
+	_leave(" = %d", ret);
+	return ret;
+}
+
+/*
+ * checksum an RxRPC packet header
+ */
+static int rxgk_secure_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
+{
+	struct rxgk_context *gk;
+	int ret;
+
+	_enter("{%d{%x}},{#%u},%u,",
+	       call->debug_id, key_serial(call->conn->key), txb->seq, txb->len);
+
+	gk = rxgk_get_key(call->conn, NULL);
+	if (IS_ERR(gk))
+		return PTR_ERR(gk) == -ESTALE ? -EKEYREJECTED : PTR_ERR(gk);
+
+	ret = key_validate(call->conn->key);
+	if (ret < 0)
+		return ret;
+
+	txb->cksum = htons(gk->key_number);
+
+	switch (call->conn->security_level) {
+	case RXRPC_SECURITY_PLAIN:
+		rxgk_put(gk);
+		txb->pkt_len = txb->len;
+		return 0;
+	case RXRPC_SECURITY_AUTH:
+		return rxgk_secure_packet_integrity(call, gk, txb);
+	case RXRPC_SECURITY_ENCRYPT:
+		return rxgk_secure_packet_encrypted(call, gk, txb);
+	default:
+		rxgk_put(gk);
+		return -EPERM;
+	}
+}
+
+/*
+ * Integrity mode (check the signature on a packet - level 1 security)
+ */
+static int rxgk_verify_packet_integrity(struct rxrpc_call *call,
+					struct rxgk_context *gk,
+					struct sk_buff *skb)
+{
+	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+	struct rxgk_header *hdr;
+	struct krb5_buffer metadata;
+	unsigned int offset = sp->offset, len = sp->len;
+	size_t data_offset = 0, data_len = len;
+	u32 ac;
+	int ret = -ENOMEM;
+
+	_enter("");
+
+	crypto_krb5_where_is_the_data(gk->krb5, KRB5_CHECKSUM_MODE,
+				      &data_offset, &data_len);
+
+	hdr = kzalloc(sizeof(*hdr), GFP_NOFS);
+	if (!hdr)
+		return -ENOMEM;
+
+	hdr->epoch	= htonl(call->conn->proto.epoch);
+	hdr->cid	= htonl(call->cid);
+	hdr->call_number = htonl(call->call_id);
+	hdr->seq	= htonl(sp->hdr.seq);
+	hdr->sec_index	= htonl(call->security_ix);
+	hdr->data_len	= htonl(data_len);
+
+	metadata.len = sizeof(*hdr);
+	metadata.data = hdr;
+	ret = rxgk_verify_mic_skb(gk->krb5, gk->rx_Kc, &metadata,
+				  skb, &offset, &len, &ac);
+	kfree(hdr);
+	if (ret == -EPROTO) {
+		rxrpc_abort_eproto(call, skb, ac,
+				   rxgk_abort_1_verify_mic_eproto);
+	} else {
+		sp->offset = offset;
+		sp->len = len;
+	}
+
+	rxgk_put(gk);
+	_leave(" = %d", ret);
+	return ret;
+}
+
+/*
+ * Decrypt an encrypted packet (level 2 security).
+ */
+static int rxgk_verify_packet_encrypted(struct rxrpc_call *call,
+					struct rxgk_context *gk,
+					struct sk_buff *skb)
+{
+	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+	struct rxgk_header hdr;
+	unsigned int offset = sp->offset, len = sp->len;
+	int ret;
+	u32 ac;
+
+	_enter("");
+
+	ret = rxgk_decrypt_skb(gk->krb5, gk->rx_enc, skb, &offset, &len, &ac);
+	if (ret == -EPROTO)
+		rxrpc_abort_eproto(call, skb, ac, rxgk_abort_2_decrypt_eproto);
+	if (ret < 0)
+		goto error;
+
+	if (len < sizeof(hdr)) {
+		ret = rxrpc_abort_eproto(call, skb, RXGK_PACKETSHORT,
+					 rxgk_abort_2_short_header);
+		goto error;
+	}
+
+	/* Extract the header from the skb */
+	ret = skb_copy_bits(skb, offset, &hdr, sizeof(hdr));
+	if (ret < 0) {
+		ret = rxrpc_abort_eproto(call, skb, RXGK_PACKETSHORT,
+					 rxgk_abort_2_short_encdata);
+		goto error;
+	}
+	offset += sizeof(hdr);
+	len -= sizeof(hdr);
+
+	if (ntohl(hdr.epoch)		!= call->conn->proto.epoch ||
+	    ntohl(hdr.cid)		!= call->cid ||
+	    ntohl(hdr.call_number)	!= call->call_id ||
+	    ntohl(hdr.seq)		!= sp->hdr.seq ||
+	    ntohl(hdr.sec_index)	!= call->security_ix ||
+	    ntohl(hdr.data_len)		> len) {
+		ret = rxrpc_abort_eproto(call, skb, RXGK_SEALED_INCON,
+					 rxgk_abort_2_short_data);
+		goto error;
+	}
+
+	sp->offset = offset;
+	sp->len = ntohl(hdr.data_len);
+	ret = 0;
+error:
+	rxgk_put(gk);
+	_leave(" = %d", ret);
+	return ret;
+}
+
+/*
+ * Verify the security on a received packet or subpacket (if part of a
+ * jumbo packet).
+ */
+static int rxgk_verify_packet(struct rxrpc_call *call, struct sk_buff *skb)
+{
+	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+	struct rxgk_context *gk;
+	u16 key_number = sp->hdr.cksum;
+
+	_enter("{%d{%x}},{#%u}",
+	       call->debug_id, key_serial(call->conn->key), sp->hdr.seq);
+
+	gk = rxgk_get_key(call->conn, &key_number);
+	if (IS_ERR(gk)) {
+		switch (PTR_ERR(gk)) {
+		case -ESTALE:
+			return rxrpc_abort_eproto(call, skb, RXGK_BADKEYNO,
+						  rxgk_abort_bad_key_number);
+		default:
+			return PTR_ERR(gk);
+		}
+	}
+
+	switch (call->conn->security_level) {
+	case RXRPC_SECURITY_PLAIN:
+		return 0;
+	case RXRPC_SECURITY_AUTH:
+		return rxgk_verify_packet_integrity(call, gk, skb);
+	case RXRPC_SECURITY_ENCRYPT:
+		return rxgk_verify_packet_encrypted(call, gk, skb);
+	default:
+		rxgk_put(gk);
+		return -ENOANO;
+	}
+}
+
+/*
+ * Allocate memory to hold a challenge or a response packet.  We're not running
+ * in the io_thread, so we can't use ->tx_alloc.
+ */
+static struct page *rxgk_alloc_packet(size_t total_len)
+{
+	gfp_t gfp = GFP_NOFS;
+	int order;
+
+	order = get_order(total_len);
+	if (order > 0)
+		gfp |= __GFP_COMP;
+	return alloc_pages(gfp, order);
+}
+
+/*
+ * Issue a challenge.
+ */
+static int rxgk_issue_challenge(struct rxrpc_connection *conn)
+{
+	struct rxrpc_wire_header *whdr;
+	struct bio_vec bvec[1];
+	struct msghdr msg;
+	struct page *page;
+	size_t len = sizeof(*whdr) + sizeof(conn->rxgk.nonce);
+	u32 serial;
+	int ret;
+
+	_enter("{%d}", conn->debug_id);
+
+	get_random_bytes(&conn->rxgk.nonce, sizeof(conn->rxgk.nonce));
+
+	/* We can't use conn->tx_alloc without a lock */
+	page = rxgk_alloc_packet(sizeof(*whdr) + sizeof(conn->rxgk.nonce));
+	if (!page)
+		return -ENOMEM;
+
+	bvec[0].bv_page	= page;
+	bvec[0].bv_len	= len;
+	iov_iter_bvec(&msg.msg_iter, WRITE, bvec, 1, len);
+
+	msg.msg_name	= &conn->peer->srx.transport;
+	msg.msg_namelen	= conn->peer->srx.transport_len;
+	msg.msg_control	= NULL;
+	msg.msg_controllen = 0;
+	msg.msg_flags	= MSG_SPLICE_PAGES;
+
+	whdr = page_address(page);
+	whdr->epoch	= htonl(conn->proto.epoch);
+	whdr->cid	= htonl(conn->proto.cid);
+	whdr->callNumber = 0;
+	whdr->seq	= 0;
+	whdr->type	= RXRPC_PACKET_TYPE_CHALLENGE;
+	whdr->flags	= conn->out_clientflag;
+	whdr->userStatus = 0;
+	whdr->securityIndex = conn->security_ix;
+	whdr->_rsvd	= 0;
+	whdr->serviceId	= htons(conn->service_id);
+
+	memcpy(whdr + 1, conn->rxgk.nonce, sizeof(conn->rxgk.nonce));
+
+	serial = rxrpc_get_next_serials(conn, 1);
+	whdr->serial = htonl(serial);
+
+	ret = do_udp_sendmsg(conn->local->socket, &msg, len);
+	if (ret > 0)
+		conn->peer->last_tx_at = ktime_get_seconds();
+	__free_page(page);
+
+	if (ret < 0) {
+		trace_rxrpc_tx_fail(conn->debug_id, serial, ret,
+				    rxrpc_tx_point_rxgk_challenge);
+		return -EAGAIN;
+	}
+
+	trace_rxrpc_tx_packet(conn->debug_id, whdr,
+			      rxrpc_tx_point_rxgk_challenge);
+	_leave(" = 0");
+	return 0;
+}
+
+/*
+ * Send a response packet.
+ */
+static int rxgk_send_response(struct rxrpc_connection *conn,
+			      struct page *page, size_t total_len)
+{
+	struct rxrpc_wire_header *whdr = page_address(page);
+	struct bio_vec bvec[1];
+	struct msghdr msg;
+	u32 serial;
+	int ret;
+
+	_enter("");
+
+	msg.msg_name	= &conn->peer->srx.transport;
+	msg.msg_namelen	= conn->peer->srx.transport_len;
+	msg.msg_control	= NULL;
+	msg.msg_controllen = 0;
+	msg.msg_flags	= MSG_SPLICE_PAGES;
+
+	bvec[0].bv_page	= page;
+	bvec[0].bv_len	= total_len;
+	iov_iter_bvec(&msg.msg_iter, WRITE, bvec, 1, total_len);
+
+	serial = rxrpc_get_next_serials(conn, 1);
+	whdr->serial = htonl(serial);
+
+	ret = do_udp_sendmsg(conn->local->socket, &msg, total_len);
+	if (ret < 0) {
+		trace_rxrpc_tx_fail(conn->debug_id, serial, ret,
+				    rxrpc_tx_point_rxgk_response);
+		return -EAGAIN;
+	}
+
+	conn->peer->last_tx_at = ktime_get_seconds();
+	_leave(" = 0");
+	return 0;
+}
+
+/*
+ * Construct the authenticator to go in the response packet
+ *
+ * struct RXGK_Authenticator {
+ *	opaque nonce[20];
+ *	opaque appdata<>;
+ *	RXGK_Level level;
+ *	unsigned int epoch;
+ *	unsigned int cid;
+ *	unsigned int call_numbers<>;
+ * };
+ */
+static void rxgk_construct_authenticator(struct rxrpc_connection *conn,
+					 const u8 *nonce, __be32 *xdr)
+{
+	memcpy(xdr, nonce, 20);
+	xdr += 5;
+	*xdr++ = htonl(0); /* appdata len */
+	*xdr++ = htonl(conn->security_level);
+	*xdr++ = htonl(conn->proto.epoch);
+	*xdr++ = htonl(conn->proto.cid);
+	*xdr++ = htonl(4); /* # call_numbers */
+	*xdr++ = htonl(conn->channels[0].call_counter);
+	*xdr++ = htonl(conn->channels[1].call_counter);
+	*xdr++ = htonl(conn->channels[2].call_counter);
+	*xdr   = htonl(conn->channels[3].call_counter);
+}
+
+/*
+ * Construct the response.
+ *
+ * struct RXGK_Response {
+ *	rxgkTime start_time;
+ *	RXGK_Data token;
+ *	opaque authenticator<RXGK_MAXAUTHENTICATOR>
+ * };
+ */
+static int rxgk_construct_response(struct rxrpc_connection *conn,
+				   struct sk_buff *challenge,
+				   const u8 *nonce)
+{
+	struct rxrpc_wire_header *whdr;
+	struct rxrpc_skb_priv *csp = rxrpc_skb(challenge);
+	struct rxgk_context *gk;
+	struct scatterlist sg[1];
+	struct page *page;
+	size_t resp_len, auth_len, authx_len, auth_offset, authx_offset;
+	__be32 *xdr;
+	void *payload;
+	int ret;
+
+	gk = rxgk_get_key(conn, NULL);
+	if (IS_ERR(gk))
+		return PTR_ERR(gk);
+
+	auth_len = 20 + 4 /* appdatalen */ + 12 + (1 + 4) * 4;
+	authx_len = crypto_krb5_how_much_buffer(gk->krb5, KRB5_ENCRYPT_MODE,
+						auth_len, &auth_offset);
+
+	resp_len  = 8;
+	resp_len += 4 + xdr_round_up(gk->key->ticket.len);
+	resp_len += 4 + xdr_round_up(authx_len);
+
+	ret = -ENOMEM;
+	page = rxgk_alloc_packet(sizeof(*whdr) + resp_len);
+	if (!page)
+		goto error_gk;
+
+	whdr = page_address(page);
+	whdr->epoch		= htonl(csp->hdr.epoch);
+	whdr->cid		= htonl(csp->hdr.cid);
+	whdr->callNumber	= 0;
+	whdr->serial		= 0;
+	whdr->seq		= 0;
+	whdr->type		= RXRPC_PACKET_TYPE_RESPONSE;
+	whdr->flags		= conn->out_clientflag;
+	whdr->userStatus	= 0;
+	whdr->securityIndex	= csp->hdr.securityIndex;
+	whdr->cksum		= htons(gk->key_number);
+	whdr->serviceId		= htons(csp->hdr.serviceId);
+
+	payload = whdr + 1;
+	xdr = payload;
+
+	*xdr++ = htonl(upper_32_bits(conn->rxgk.start_time));
+	*xdr++ = htonl(lower_32_bits(conn->rxgk.start_time));
+	*xdr++ = htonl(gk->key->ticket.len);
+	memcpy(xdr, gk->key->ticket.data, xdr_round_up(gk->key->ticket.len));
+	xdr += xdr_round_up(gk->key->ticket.len) / sizeof(*xdr);
+	*xdr++ = htonl(authx_len);
+
+	authx_offset = (void *)xdr - payload;
+	auth_offset += authx_offset;
+
+	xdr = (void *)payload + auth_offset;
+	rxgk_construct_authenticator(conn, nonce, xdr);
+
+	sg_init_table(sg, 1);
+	sg_set_buf(&sg[0], payload + authx_offset, authx_len);
+	ret = crypto_krb5_encrypt(gk->krb5, gk->resp_enc,
+				  sg, 1, authx_len,
+				  auth_offset - authx_offset, auth_len, false);
+	if (ret < 0)
+		goto error;
+
+	ret = rxgk_send_response(conn, page, sizeof(*whdr) + authx_offset + ret);
+error:
+	__free_page(page);
+error_gk:
+	rxgk_put(gk);
+	_leave(" = %d", ret);
+	return ret;
+}
+
+/*
+ * Respond to a challenge packet
+ */
+static int rxgk_respond_to_challenge(struct rxrpc_connection *conn,
+				     struct sk_buff *skb)
+{
+	u8 nonce[20];
+
+	_enter("{%d,%x}", conn->debug_id, key_serial(conn->key));
+
+	if (!conn->key)
+		return rxrpc_abort_conn(conn, skb, RX_PROTOCOL_ERROR, -EPROTO,
+					rxgk_abort_chall_no_key);
+
+	if (key_validate(conn->key) < 0)
+		return rxrpc_abort_conn(conn, skb, RXGK_EXPIRED, -EPROTO,
+					rxgk_abort_chall_key_expired);
+
+	if (skb_copy_bits(skb, sizeof(struct rxrpc_wire_header),
+			  nonce, sizeof(nonce)) < 0)
+		return rxrpc_abort_conn(conn, skb, RXGK_PACKETSHORT, -EPROTO,
+					rxgk_abort_chall_short);
+
+	return rxgk_construct_response(conn, skb, nonce);
+}
+
+/*
+ * Verify the authenticator.
+ *
+ * struct RXGK_Authenticator {
+ *	opaque nonce[20];
+ *	opaque appdata<>;
+ *	RXGK_Level level;
+ *	unsigned int epoch;
+ *	unsigned int cid;
+ *	unsigned int call_numbers<>;
+ * };
+ */
+static int rxgk_do_verify_authenticator(struct rxrpc_connection *conn,
+					const struct krb5_enctype *krb5,
+					struct sk_buff *skb,
+					__be32 *p, __be32 *end)
+{
+	u32 app_len, call_count, level, epoch, cid, i;
+
+	_enter("");
+
+	if (memcmp(p, conn->rxgk.nonce, 20) != 0)
+		return rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EPROTO,
+					rxgk_abort_resp_bad_nonce);
+	p += 20 / sizeof(__be32);
+
+	app_len	= ntohl(*p++);
+	if (app_len > (end - p) * sizeof(__be32))
+		return rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EPROTO,
+					rxgk_abort_resp_short_applen);
+
+	p += xdr_round_up(app_len) / sizeof(__be32);
+	if (end - p < 4)
+		return rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EPROTO,
+					rxgk_abort_resp_short_applen);
+
+	level	= ntohl(*p++);
+	epoch	= ntohl(*p++);
+	cid	= ntohl(*p++);
+	call_count = ntohl(*p++);
+
+	if (level	!= conn->security_level ||
+	    epoch	!= conn->proto.epoch ||
+	    cid		!= conn->proto.cid ||
+	    call_count	> 4)
+		return rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EPROTO,
+					rxgk_abort_resp_bad_param);
+
+	if (end - p < call_count)
+		return rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EPROTO,
+					rxgk_abort_resp_short_call_list);
+
+	for (i = 0; i < call_count; i++) {
+		u32 call_id = ntohl(*p++);
+
+		if (call_id > INT_MAX)
+			return rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EPROTO,
+						rxgk_abort_resp_bad_callid);
+
+		if (call_id < conn->channels[i].call_counter)
+			return rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EPROTO,
+						rxgk_abort_resp_call_ctr);
+
+		if (call_id > conn->channels[i].call_counter) {
+			if (conn->channels[i].call)
+				return rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EPROTO,
+							rxgk_abort_resp_call_state);
+
+			conn->channels[i].call_counter = call_id;
+		}
+	}
+
+	_leave(" = 0");
+	return 0;
+}
+
+/*
+ * Extract the authenticator and verify it.
+ */
+static int rxgk_verify_authenticator(struct rxrpc_connection *conn,
+				     const struct krb5_enctype *krb5,
+				     struct sk_buff *skb,
+				     unsigned int auth_offset, unsigned int auth_len)
+{
+	void *auth;
+	__be32 *p;
+	int ret;
+
+	auth = kmalloc(auth_len, GFP_NOFS);
+	if (!auth)
+		return -ENOMEM;
+
+	ret = skb_copy_bits(skb, auth_offset, auth, auth_len);
+	if (ret < 0) {
+		ret = rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EPROTO,
+				       rxgk_abort_resp_short_auth);
+		goto error;
+	}
+
+	p = auth;
+	ret = rxgk_do_verify_authenticator(conn, krb5, skb, p, p + auth_len);
+error:
+	kfree(auth);
+	return ret;
+}
+
+/*
+ * Verify a response.
+ *
+ * struct RXGK_Response {
+ *	rxgkTime	start_time;
+ *	RXGK_Data	token;
+ *	opaque		authenticator<RXGK_MAXAUTHENTICATOR>
+ * };
+ */
+static int rxgk_verify_response(struct rxrpc_connection *conn,
+				struct sk_buff *skb)
+{
+	const struct krb5_enctype *krb5;
+	struct rxrpc_key_token *token;
+	struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+	struct rxgk_response rhdr;
+	struct rxgk_context *gk;
+	struct key *key = NULL;
+	unsigned int offset = sizeof(struct rxrpc_wire_header);
+	unsigned int len = skb->len - sizeof(struct rxrpc_wire_header);
+	unsigned int token_offset, token_len;
+	unsigned int auth_offset, auth_len;
+	__be32 xauth_len;
+	int ret, ec;
+
+	_enter("{%d}", conn->debug_id);
+
+	/* Parse the RXGK_Response object */
+	if (sizeof(rhdr) + sizeof(__be32) > len)
+		goto short_packet;
+
+	if (skb_copy_bits(skb, offset, &rhdr, sizeof(rhdr)) < 0)
+		goto short_packet;
+	offset	+= sizeof(rhdr);
+	len	-= sizeof(rhdr);
+
+	token_offset	= offset;
+	token_len	= ntohl(rhdr.token_len);
+	if (xdr_round_up(token_len) + sizeof(__be32) > len)
+		goto short_packet;
+
+	offset	+= xdr_round_up(token_len);
+	len	-= xdr_round_up(token_len);
+
+	if (skb_copy_bits(skb, offset, &xauth_len, sizeof(xauth_len)) < 0)
+		goto short_packet;
+	offset	+= sizeof(xauth_len);
+	len	-= sizeof(xauth_len);
+
+	auth_offset	= offset;
+	auth_len	= ntohl(xauth_len);
+	if (auth_len < len)
+		goto short_packet;
+	if (auth_len & 3)
+		goto inconsistent;
+	if (auth_len < 20 + 9 * 4)
+		goto auth_too_short;
+
+	/* We need to extract and decrypt the token and instantiate a session
+	 * key for it.  This bit, however, is application-specific.  If
+	 * possible, we use a default parser, but we might end up bumping this
+	 * to the app to deal with - which might mean a round trip to
+	 * userspace.
+	 */
+	ret = rxgk_extract_token(conn, skb, token_offset, token_len, &key);
+	if (ret < 0)
+		goto out;
+
+	/* We now have a key instantiated from the decrypted ticket.  We can
+	 * pass this to the application so that they can parse the ticket
+	 * content and we can use the session key it contains to derive the
+	 * keys we need.
+	 *
+	 * Note that we have to switch enctype at this point as the enctype of
+	 * the ticket doesn't necessarily match that of the transport.
+	 */
+	token = key->payload.data[0];
+	conn->security_level = token->rxgk->level;
+	conn->rxgk.start_time = __be64_to_cpu(rhdr.start_time);
+
+	gk = rxgk_generate_transport_key(conn, token->rxgk, sp->hdr.cksum, GFP_NOFS);
+	if (IS_ERR(gk)) {
+		ret = PTR_ERR(gk);
+		goto cant_get_token;
+	}
+
+	krb5 = gk->krb5;
+
+	/* Decrypt, parse and verify the authenticator. */
+	ret = rxgk_decrypt_skb(krb5, gk->resp_enc, skb,
+			       &auth_offset, &auth_len, &ec);
+	if (ret < 0) {
+		rxrpc_abort_conn(conn, skb, RXGK_SEALED_INCON, ret,
+				 rxgk_abort_resp_auth_dec);
+		goto out;
+	}
+
+	ret = rxgk_verify_authenticator(conn, krb5, skb, auth_offset, auth_len);
+	if (ret < 0)
+		goto out;
+
+	conn->key = key;
+	key = NULL;
+	ret = 0;
+out:
+	key_put(key);
+	_leave(" = %d", ret);
+	return ret;
+
+inconsistent:
+	ret = rxrpc_abort_conn(conn, skb, RXGK_INCONSISTENCY, -EPROTO,
+			       rxgk_abort_resp_xdr_align);
+	goto out;
+auth_too_short:
+	ret = rxrpc_abort_conn(conn, skb, RXGK_PACKETSHORT, -EPROTO,
+			       rxgk_abort_resp_short_auth);
+	goto out;
+short_packet:
+	ret = rxrpc_abort_conn(conn, skb, RXGK_PACKETSHORT, -EPROTO,
+			       rxgk_abort_resp_short_packet);
+	goto out;
+
+cant_get_token:
+	switch (ret) {
+	case -ENOMEM:
+		goto temporary_error;
+	case -EINVAL:
+		ret = rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EKEYREJECTED,
+				       rxgk_abort_resp_internal_error);
+		goto out;
+	case -ENOPKG:
+		ret = rxrpc_abort_conn(conn, skb, RXGK_BADETYPE, -EKEYREJECTED,
+				       rxgk_abort_resp_nopkg);
+		goto out;
+	}
+
+temporary_error:
+	/* Ignore the response packet if we got a temporary error such as
+	 * ENOMEM.  We just want to send the challenge again.  Note that we
+	 * also come out this way if the ticket decryption fails.
+	 */
+	goto out;
+}
+
+/*
+ * clear the connection security
+ */
+static void rxgk_clear(struct rxrpc_connection *conn)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(conn->rxgk.keys); i++)
+		rxgk_put(conn->rxgk.keys[i]);
+}
+
+/*
+ * Initialise the RxGK security service.
+ */
+static int rxgk_init(void)
+{
+	return 0;
+}
+
+/*
+ * Clean up the RxGK security service.
+ */
+static void rxgk_exit(void)
+{
+}
+
+/*
+ * RxRPC YFS GSSAPI-based security
+ */
+const struct rxrpc_security rxgk_yfs = {
+	.name				= "yfs-rxgk",
+	.security_index			= RXRPC_SECURITY_YFS_RXGK,
+	.no_key_abort			= RXGK_NOTAUTH,
+	.init				= rxgk_init,
+	.exit				= rxgk_exit,
+	.preparse_server_key		= rxgk_preparse_server_key,
+	.free_preparse_server_key	= rxgk_free_preparse_server_key,
+	.destroy_server_key		= rxgk_destroy_server_key,
+	.describe_server_key		= rxgk_describe_server_key,
+	.init_connection_security	= rxgk_init_connection_security,
+	.alloc_txbuf			= rxgk_alloc_txbuf,
+	.secure_packet			= rxgk_secure_packet,
+	.verify_packet			= rxgk_verify_packet,
+	.free_call_crypto		= rxgk_free_call_crypto,
+	.issue_challenge		= rxgk_issue_challenge,
+	.respond_to_challenge		= rxgk_respond_to_challenge,
+	.verify_response		= rxgk_verify_response,
+	.clear				= rxgk_clear,
+	.default_decode_ticket		= rxgk_yfs_decode_ticket,
+};
diff --git a/net/rxrpc/rxgk_app.c b/net/rxrpc/rxgk_app.c
new file mode 100644
index 000000000000..6ca9d1d3e4c6
--- /dev/null
+++ b/net/rxrpc/rxgk_app.c
@@ -0,0 +1,284 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Application-specific bits for GSSAPI-based RxRPC security
+ *
+ * Copyright (C) 2023 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/net.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/key-type.h>
+#include "ar-internal.h"
+#include "rxgk_common.h"
+
+/*
+ * Decode a default-style YFS ticket in a response and turn it into an
+ * rxrpc-type key.
+ *
+ * struct rxgk_key {
+ *	afs_uint32	enctype;
+ *	opaque		key<>;
+ * };
+ *
+ * struct RXGK_AuthName {
+ *	afs_int32	kind;
+ *	opaque		data<AUTHDATAMAX>;
+ *	opaque		display<AUTHPRINTABLEMAX>;
+ * };
+ *
+ * struct RXGK_Token {
+ *	rxgk_key		K0;
+ *	RXGK_Level		level;
+ *	rxgkTime		starttime;
+ *	afs_int32		lifetime;
+ *	afs_int32		bytelife;
+ *	rxgkTime		expirationtime;
+ *	struct RXGK_AuthName	identities<>;
+ * };
+ */
+int rxgk_yfs_decode_ticket(struct rxrpc_connection *conn, struct sk_buff *skb,
+			   unsigned int ticket_offset, unsigned int ticket_len,
+			   struct key **_key)
+{
+	struct rxrpc_key_token *token;
+	const struct cred *cred = current_cred(); // TODO - use socket creds
+	struct key *key;
+	size_t pre_ticket_len, payload_len;
+	unsigned int klen, enctype;
+	void *payload, *ticket;
+	__be32 *t, *p, *q, tmp[2];
+	int ret;
+
+	_enter("");
+
+	/* Get the session key length */
+	ret = skb_copy_bits(skb, ticket_offset, tmp, sizeof(tmp));
+	if (ret < 0)
+		return rxrpc_abort_conn(conn, skb, RXGK_INCONSISTENCY, -EPROTO,
+					rxgk_abort_resp_short_yfs_klen);
+	enctype = ntohl(tmp[0]);
+	klen = ntohl(tmp[1]);
+
+	if (klen > ticket_len - 10 * sizeof(__be32))
+		return rxrpc_abort_conn(conn, skb, RXGK_INCONSISTENCY, -EPROTO,
+					rxgk_abort_resp_short_yfs_key);
+
+	pre_ticket_len = ((5 + 14) * sizeof(__be32) +
+			  xdr_round_up(klen) +
+			  sizeof(__be32));
+	payload_len = pre_ticket_len + xdr_round_up(ticket_len);
+
+	payload = kzalloc(payload_len, GFP_NOFS);
+	if (!payload)
+		return -ENOMEM;
+
+	/* We need to fill out the XDR form for a key payload that we can pass
+	 * to add_key().  Start by copying in the ticket so that we can parse
+	 * it.
+	 */
+	ticket = payload + pre_ticket_len;
+	ret = skb_copy_bits(skb, ticket_offset, ticket, ticket_len);
+	if (ret < 0) {
+		ret = rxrpc_abort_conn(conn, skb, RXGK_INCONSISTENCY, -EPROTO,
+				       rxgk_abort_resp_short_yfs_tkt);
+		goto error;
+	}
+
+	/* Fill out the form header. */
+	p = payload;
+	p[0] = htonl(0); /* Flags */
+	p[1] = htonl(1); /* len(cellname) */
+	p[2] = htonl(0x20000000); /* Cellname " " */
+	p[3] = htonl(1); /* #tokens */
+	p[4] = htonl(15 * sizeof(__be32) + xdr_round_up(klen) +
+		     xdr_round_up(ticket_len)); /* Token len */
+
+	/* Now fill in the body.  Most of this we can just scrape directly from
+	 * the ticket.
+	 */
+	t = ticket + sizeof(__be32) * 2 + xdr_round_up(klen);
+	q = payload + 5 * sizeof(__be32);
+	q[0]  = htonl(RXRPC_SECURITY_YFS_RXGK);
+	q[1]  = t[1];		/* begintime - msw */
+	q[2]  = t[2];		/* - lsw */
+	q[3]  = t[5];		/* endtime - msw */
+	q[4]  = t[6];		/* - lsw */
+	q[5]  = 0;		/* level - msw */
+	q[6]  = t[0];		/* - lsw */
+	q[7]  = 0;		/* lifetime - msw */
+	q[8]  = t[3];		/* - lsw */
+	q[9]  = 0;		/* bytelife - msw */
+	q[10] = t[4];		/* - lsw */
+	q[11] = 0;		/* enctype - msw */
+	q[12] = htonl(enctype);	/* - lsw */
+	q[13] = htonl(klen);	/* Key length */
+
+	q += 14;
+
+	memcpy(q, ticket + sizeof(__be32) * 2, klen);
+	q += xdr_round_up(klen) / 4;
+	q[0] = htonl(ticket_len);
+	q++;
+	if (WARN_ON((unsigned long)q != (unsigned long)ticket)) {
+		ret = -EIO;
+		goto error;
+	}
+
+	/* Ticket read in with skb_copy_bits above */
+	q += xdr_round_up(ticket_len) / 4;
+	if (WARN_ON((unsigned long)q - (unsigned long)payload != payload_len)) {
+		ret = -EIO;
+		goto error;
+	}
+
+	/* Now turn that into a key. */
+	key = key_alloc(&key_type_rxrpc, "x",
+			GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred, 0, // TODO: Use socket owner
+			KEY_ALLOC_NOT_IN_QUOTA, NULL);
+	if (IS_ERR(key)) {
+		_leave(" = -ENOMEM [alloc %ld]", PTR_ERR(key));
+		goto error;
+	}
+
+	_debug("key %d", key_serial(key));
+
+	ret = key_instantiate_and_link(key, payload, payload_len, NULL, NULL);
+	if (ret < 0)
+		goto error_key;
+
+	token = key->payload.data[0];
+	token->no_leak_key = true;
+	*_key = key;
+	key = NULL;
+	ret = 0;
+	goto error;
+
+error_key:
+	key_put(key);
+error:
+	kfree_sensitive(payload);
+	_leave(" = %d", ret);
+	return ret;
+}
+
+/*
+ * Extract the token and set up a session key from the details.
+ *
+ * struct RXGK_TokenContainer {
+ *	afs_int32	kvno;
+ *	afs_int32	enctype;
+ *	opaque		encrypted_token<>;
+ * };
+ *
+ * [tools.ietf.org/html/draft-wilkinson-afs3-rxgk-afs-08 sec 6.1]
+ */
+int rxgk_extract_token(struct rxrpc_connection *conn, struct sk_buff *skb,
+		       unsigned int token_offset, unsigned int token_len,
+		       struct key **_key)
+{
+	const struct krb5_enctype *krb5;
+	const struct krb5_buffer *server_secret;
+	struct crypto_aead *token_enc = NULL;
+	struct key *server_key;
+	unsigned int ticket_offset, ticket_len;
+	u32 kvno, enctype;
+	int ret, ec;
+
+	struct {
+		__be32 kvno;
+		__be32 enctype;
+		__be32 token_len;
+	} container;
+
+	/* Decode the RXGK_TokenContainer object.  This tells us which server
+	 * key we should be using.  We can then fetch the key, get the secret
+	 * and set up the crypto to extract the token.
+	 */
+	if (skb_copy_bits(skb, token_offset, &container, sizeof(container)) < 0)
+		return rxrpc_abort_conn(conn, skb, RXGK_PACKETSHORT, -EPROTO,
+					rxgk_abort_resp_tok_short);
+
+	kvno		= ntohl(container.kvno);
+	enctype		= ntohl(container.enctype);
+	ticket_len	= ntohl(container.token_len);
+	ticket_offset	= token_offset + sizeof(container);
+
+	if (xdr_round_up(ticket_len) > token_len - 3 * 4)
+		return rxrpc_abort_conn(conn, skb, RXGK_PACKETSHORT, -EPROTO,
+					rxgk_abort_resp_tok_short);
+
+	_debug("KVNO %u", kvno);
+	_debug("ENC  %u", enctype);
+	_debug("TLEN %u", ticket_len);
+
+	server_key = rxrpc_look_up_server_security(conn, skb, kvno, enctype);
+	if (IS_ERR(server_key))
+		goto cant_get_server_key;
+
+	down_read(&server_key->sem);
+	server_secret = (const void *)&server_key->payload.data[2];
+	ret = rxgk_set_up_token_cipher(server_secret, &token_enc, enctype, &krb5, GFP_NOFS);
+	up_read(&server_key->sem);
+	key_put(server_key);
+	if (ret < 0)
+		goto cant_get_token;
+
+	/* We can now decrypt and parse the token/ticket.  This allows us to
+	 * gain access to K0, from which we can derive the transport key and
+	 * thence decode the authenticator.
+	 */
+	ret = rxgk_decrypt_skb(krb5, token_enc, skb,
+			       &ticket_offset, &ticket_len, &ec);
+	crypto_free_aead(token_enc);
+	token_enc = NULL;
+	if (ret < 0)
+		return rxrpc_abort_conn(conn, skb, ec, ret,
+					rxgk_abort_resp_tok_dec);
+
+	ret = conn->security->default_decode_ticket(conn, skb, ticket_offset,
+						    ticket_len, _key);
+	if (ret < 0)
+		goto cant_get_token;
+
+	_leave(" = 0");
+	return ret;
+
+cant_get_server_key:
+	ret = PTR_ERR(server_key);
+	switch (ret) {
+	case -ENOMEM:
+		goto temporary_error;
+	case -ENOKEY:
+	case -EKEYREJECTED:
+	case -EKEYEXPIRED:
+	case -EKEYREVOKED:
+	case -EPERM:
+		return rxrpc_abort_conn(conn, skb, RXGK_BADKEYNO, -EKEYREJECTED,
+					rxgk_abort_resp_tok_nokey);
+	default:
+		return rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EKEYREJECTED,
+					rxgk_abort_resp_tok_keyerr);
+	}
+
+cant_get_token:
+	switch (ret) {
+	case -ENOMEM:
+		goto temporary_error;
+	case -EINVAL:
+		return rxrpc_abort_conn(conn, skb, RXGK_NOTAUTH, -EKEYREJECTED,
+					rxgk_abort_resp_tok_internal_error);
+	case -ENOPKG:
+		return rxrpc_abort_conn(conn, skb, RXGK_BADETYPE, -EKEYREJECTED,
+					rxgk_abort_resp_tok_nopkg);
+	}
+
+temporary_error:
+	/* Ignore the response packet if we got a temporary error such as
+	 * ENOMEM.  We just want to send the challenge again.  Note that we
+	 * also come out this way if the ticket decryption fails.
+	 */
+	return ret;
+}
diff --git a/net/rxrpc/rxgk_common.h b/net/rxrpc/rxgk_common.h
index c07a5386b303..e5becb16fe64 100644
--- a/net/rxrpc/rxgk_common.h
+++ b/net/rxrpc/rxgk_common.h
@@ -33,6 +33,18 @@ struct rxgk_context {
 	struct crypto_aead	*resp_enc;	/* Response packet enc key */
 };
 
+#define xdr_round_up(x) (round_up((x), sizeof(__be32)))
+
+/*
+ * rxgk_app.c
+ */
+int rxgk_yfs_decode_ticket(struct rxrpc_connection *conn, struct sk_buff *skb,
+			   unsigned int ticket_offset, unsigned int ticket_len,
+			   struct key **_key);
+int rxgk_extract_token(struct rxrpc_connection *conn, struct sk_buff *skb,
+		       unsigned int token_offset, unsigned int token_len,
+		       struct key **_key);
+
 /*
  * rxgk_kdf.c
  */
@@ -46,3 +58,83 @@ int rxgk_set_up_token_cipher(const struct krb5_buffer *server_key,
 			     unsigned int enctype,
 			     const struct krb5_enctype **_krb5,
 			     gfp_t gfp);
+
+/*
+ * Apply decryption and checksumming functions to part of an skbuff.  The
+ * offset and length are updated to reflect the actual content of the encrypted
+ * region.
+ */
+static inline
+int rxgk_decrypt_skb(const struct krb5_enctype *krb5,
+		     struct crypto_aead *aead,
+		     struct sk_buff *skb,
+		     unsigned int *_offset, unsigned int *_len,
+		     int *_error_code)
+{
+	struct scatterlist sg[16];
+	size_t offset = 0, len = *_len;
+	int nr_sg, ret;
+
+	sg_init_table(sg, ARRAY_SIZE(sg));
+	nr_sg = skb_to_sgvec(skb, sg, *_offset, len);
+	if (unlikely(nr_sg < 0))
+		return nr_sg;
+
+	ret = crypto_krb5_decrypt(krb5, aead, sg, nr_sg,
+				  &offset, &len);
+	switch (ret) {
+	case 0:
+		*_offset += offset;
+		*_len = len;
+		break;
+	case -EPROTO:
+	case -EBADMSG:
+		*_error_code = RXGK_SEALED_INCON;
+		break;
+	default:
+		break;
+	}
+
+	return ret;
+}
+
+/*
+ * Check the MIC on a region of an skbuff.  The offset and length are updated
+ * to reflect the actual content of the secure region.
+ */
+static inline
+int rxgk_verify_mic_skb(const struct krb5_enctype *krb5,
+			struct crypto_shash *shash,
+			const struct krb5_buffer *metadata,
+			struct sk_buff *skb,
+			unsigned int *_offset, unsigned int *_len,
+			u32 *_error_code)
+{
+	struct scatterlist sg[16];
+	size_t offset = 0, len = *_len;
+	int nr_sg, ret;
+
+	sg_init_table(sg, ARRAY_SIZE(sg));
+	nr_sg = skb_to_sgvec(skb, sg, *_offset, len);
+	if (unlikely(nr_sg < 0))
+		return nr_sg;
+
+	ret = crypto_krb5_verify_mic(krb5, shash, metadata, sg, nr_sg,
+				     &offset, &len);
+	switch (ret) {
+	case 0:
+		*_offset += offset;
+		*_len = len;
+		break;
+	case -EPROTO:
+	case -EBADMSG:
+		*_error_code = RXGK_SEALED_INCON;
+		break;
+	default:
+		break;
+	}
+
+	*_offset += offset;
+	*_len = len;
+	return ret;
+}
diff --git a/net/rxrpc/rxkad.c b/net/rxrpc/rxkad.c
index 62b09d23ec08..773405b55392 100644
--- a/net/rxrpc/rxkad.c
+++ b/net/rxrpc/rxkad.c
@@ -177,8 +177,10 @@ static struct rxrpc_txbuf *rxkad_alloc_txbuf(struct rxrpc_call *call, size_t rem
 	if (!txb)
 		return NULL;
 
-	txb->offset += shdr;
-	txb->space = part;
+	txb->crypto_header	= 0;
+	txb->sec_header		= shdr;
+	txb->offset		+= shdr;
+	txb->space		= part;
 	return txb;
 }
 
diff --git a/net/rxrpc/security.c b/net/rxrpc/security.c
index 9784adc8f275..078d91a6b77f 100644
--- a/net/rxrpc/security.c
+++ b/net/rxrpc/security.c
@@ -20,6 +20,9 @@ static const struct rxrpc_security *rxrpc_security_types[] = {
 #ifdef CONFIG_RXKAD
 	[RXRPC_SECURITY_RXKAD]	= &rxkad,
 #endif
+#ifdef CONFIG_RXGK
+	[RXRPC_SECURITY_YFS_RXGK] = &rxgk_yfs,
+#endif
 };
 
 int __init rxrpc_init_security(void)

[RFC PATCH 24/24] rxrpc: rxgk: Implement connection rekeying

[David Howells]

Implement rekeying of connections with the RxGK security class.  This
involves regenerating the keys with a different key number as part of the
input data after a certain amount of time or a certain amount of bytes
encrypted.  Rekeying may be triggered by either end.

The LSW of the key number is inserted into the security-specific field in
the RX header, and we try and expand it to 32-bits to make it last longer.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
cc: "David S. Miller" <davem@davemloft.net>
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: linux-crypto@vger.kernel.org
cc: netdev@vger.kernel.org
---
 net/rxrpc/ar-internal.h |   5 +-
 net/rxrpc/conn_object.c |   1 +
 net/rxrpc/rxgk.c        | 156 ++++++++++++++++++++++++++++++++++++++--
 3 files changed, 155 insertions(+), 7 deletions(-)

diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 736dc6ea20ac..e00f3b0edc98 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -533,11 +533,14 @@ struct rxrpc_connection {
 			u32	nonce;		/* response re-use preventer */
 		} rxkad;
 		struct {
-			struct rxgk_context *keys[1];
+			struct rxgk_context *keys[4]; /* (Re-)keying buffer */
 			u64	start_time;	/* The start time for TK derivation */
 			u8	nonce[20];	/* Response re-use preventer */
+			u32	key_number;	/* Current key number */
 		} rxgk;
 	};
+	rwlock_t		security_use_lock; /* Security use/modification lock */
+
 	unsigned long		flags;
 	unsigned long		events;
 	unsigned long		idle_timestamp;	/* Time at which last became idle */
diff --git a/net/rxrpc/conn_object.c b/net/rxrpc/conn_object.c
index 7eba4d7d9a38..56459b00266d 100644
--- a/net/rxrpc/conn_object.c
+++ b/net/rxrpc/conn_object.c
@@ -72,6 +72,7 @@ struct rxrpc_connection *rxrpc_alloc_connection(struct rxrpc_net *rxnet,
 		skb_queue_head_init(&conn->rx_queue);
 		conn->rxnet = rxnet;
 		conn->security = &rxrpc_no_security;
+		rwlock_init(&conn->security_use_lock);
 		spin_lock_init(&conn->state_lock);
 		conn->debug_id = atomic_inc_return(&rxrpc_debug_id);
 		conn->idle_timestamp = jiffies;
diff --git a/net/rxrpc/rxgk.c b/net/rxrpc/rxgk.c
index 9c5c616c40cb..367d65aa7731 100644
--- a/net/rxrpc/rxgk.c
+++ b/net/rxrpc/rxgk.c
@@ -76,11 +76,153 @@ static void rxgk_describe_server_key(const struct key *key, struct seq_file *m)
 		seq_printf(m, ": %s", krb5->name);
 }
 
+/*
+ * Handle rekeying the connection when we see our limits overrun or when the
+ * far side decided to rekey.
+ *
+ * Returns a ref on the context if successful or -ESTALE if the key is out of
+ * date.
+ */
+static struct rxgk_context *rxgk_rekey(struct rxrpc_connection *conn,
+				       const u16 *specific_key_number)
+{
+	struct rxgk_context *gk, *dead = NULL;
+	unsigned int key_number, current_key, mask = ARRAY_SIZE(conn->rxgk.keys) - 1;
+	bool crank = false;
+
+	_enter("%d", specific_key_number ? *specific_key_number : -1);
+
+	mutex_lock(&conn->security_lock);
+
+	current_key = conn->rxgk.key_number;
+	if (!specific_key_number) {
+		key_number = current_key;
+	} else {
+		if (*specific_key_number == (u16)current_key)
+			key_number = current_key;
+		else if (*specific_key_number == (u16)(current_key - 1))
+			key_number = current_key - 1;
+		else if (*specific_key_number == (u16)(current_key + 1))
+			goto crank_window;
+		else
+			goto bad_key;
+	}
+
+	gk = conn->rxgk.keys[key_number & mask];
+	if (!gk)
+		goto generate_key;
+	if (!specific_key_number &&
+	    test_bit(RXGK_TK_NEEDS_REKEY, &gk->flags))
+		goto crank_window;
+
+grab:
+	refcount_inc(&gk->usage);
+	mutex_unlock(&conn->security_lock);
+	rxgk_put(dead);
+	return gk;
+
+crank_window:
+	if (current_key == UINT_MAX)
+		goto bad_key;
+	if (current_key + 1 == UINT_MAX)
+		set_bit(RXRPC_CONN_DONT_REUSE, &conn->flags);
+
+	key_number = current_key + 1;
+	if (WARN_ON(conn->rxgk.keys[key_number & mask]))
+		goto bad_key;
+	crank = true;
+
+generate_key:
+	gk = conn->rxgk.keys[current_key & mask];
+	gk = rxgk_generate_transport_key(conn, gk->key, key_number, GFP_NOFS);
+	if (IS_ERR(gk)) {
+		mutex_unlock(&conn->security_lock);
+		return gk;
+	}
+
+	write_lock(&conn->security_use_lock);
+	if (crank) {
+		current_key++;
+		conn->rxgk.key_number = current_key;
+		dead = conn->rxgk.keys[(current_key - 2) & mask];
+		conn->rxgk.keys[(current_key - 2) & mask] = NULL;
+	}
+	conn->rxgk.keys[current_key & mask] = gk;
+	write_unlock(&conn->security_use_lock);
+	goto grab;
+
+bad_key:
+	mutex_unlock(&conn->security_lock);
+	return ERR_PTR(-ESTALE);
+}
+
+/*
+ * Get the specified keying context.
+ *
+ * Returns a ref on the context if successful or -ESTALE if the key is out of
+ * date.
+ */
 static struct rxgk_context *rxgk_get_key(struct rxrpc_connection *conn,
-					 u16 *specific_key_number)
+					 const u16 *specific_key_number)
 {
-	refcount_inc(&conn->rxgk.keys[0]->usage);
-	return conn->rxgk.keys[0];
+	struct rxgk_context *gk;
+	unsigned int key_number, current_key, mask = ARRAY_SIZE(conn->rxgk.keys) - 1;
+
+	_enter("{%u},%d",
+	       conn->rxgk.key_number, specific_key_number ? *specific_key_number : -1);
+
+	read_lock(&conn->security_use_lock);
+
+	current_key = conn->rxgk.key_number;
+	if (!specific_key_number) {
+		key_number = current_key;
+	} else {
+		/* Only the bottom 16 bits of the key number are exposed in the
+		 * header, so we try and keep the upper 16 bits in step.  The
+		 * whole 32 bits are used to generate the TK.
+		 */
+		if (*specific_key_number == (u16)current_key)
+			key_number = current_key;
+		else if (*specific_key_number == (u16)(current_key - 1))
+			key_number = current_key - 1;
+		else if (*specific_key_number == (u16)(current_key + 1))
+			goto rekey;
+		else
+			goto bad_key;
+	}
+
+	gk = conn->rxgk.keys[key_number & mask];
+	if (!gk)
+		goto slow_path;
+	if (!specific_key_number &&
+	    key_number < UINT_MAX) {
+		if (time_after(jiffies, gk->expiry) ||
+		    gk->bytes_remaining < 0) {
+			set_bit(RXGK_TK_NEEDS_REKEY, &gk->flags);
+			goto slow_path;
+		}
+
+		if (test_bit(RXGK_TK_NEEDS_REKEY, &gk->flags))
+			goto slow_path;
+	}
+
+	refcount_inc(&gk->usage);
+	read_unlock(&conn->security_use_lock);
+	return gk;
+
+rekey:
+	_debug("rekey");
+	if (current_key == UINT_MAX)
+		goto bad_key;
+	gk = conn->rxgk.keys[current_key & mask];
+	if (gk)
+		set_bit(RXGK_TK_NEEDS_REKEY, &gk->flags);
+slow_path:
+	read_unlock(&conn->security_use_lock);
+	return rxgk_rekey(conn, specific_key_number);
+bad_key:
+	read_unlock(&conn->security_use_lock);
+	return ERR_PTR(-ESTALE);
 }
 
 /*
@@ -92,7 +234,8 @@ static int rxgk_init_connection_security(struct rxrpc_connection *conn,
 	struct rxgk_context *gk;
 	int ret;
 
-	_enter("{%d},{%x}", conn->debug_id, key_serial(conn->key));
+	_enter("{%d,%u},{%x}",
+	       conn->debug_id, conn->rxgk.key_number, key_serial(conn->key));
 
 	conn->security_ix = token->security_index;
 	conn->security_level = token->rxgk->level;
@@ -102,10 +245,11 @@ static int rxgk_init_connection_security(struct rxrpc_connection *conn,
 		do_div(conn->rxgk.start_time, 100);
 	}
 
-	gk = rxgk_generate_transport_key(conn, token->rxgk, 0, GFP_NOFS);
+	gk = rxgk_generate_transport_key(conn, token->rxgk, conn->rxgk.key_number,
+					 GFP_NOFS);
 	if (IS_ERR(gk))
 		return PTR_ERR(gk);
-	conn->rxgk.keys[0] = gk;
+	conn->rxgk.keys[gk->key_number & 3] = gk;
 
 	switch (conn->security_level) {
 	case RXRPC_SECURITY_PLAIN:

Re: [RFC PATCH 00/24] crypto: Add generic Kerberos library with AEAD template for hash-then-crypt

[Chuck Lever]

On 1/17/25 1:35 PM, David Howells wrote:
> Hi Herbert, Chuck,
> 
> Here's yet another go at a generic Kerberos crypto library in the kernel so
> that I can share code between rxrpc and sunrpc (and cifs?).  I derived some
> of the parts from the sunrpc gss library and added more advanced AES and
> Camellia crypto.
> 
> I added an addition AEAD template type, derived from authenc, that does
> hash-then-crypt rather than crypt-then-hash as authenc does.  I called it
> "krb5enc" for want of a better name.  Possibly I should call it "hashenc"
> or something like that.
> 
> I went back to my previous more library-based approach, but for encrypt
> mode, I replaced the separate skcipher and shash objects with a single
> templated AEAD object - either krb5enc (AES+SHA1 and Camellia) or authenc
> (AES+SHA2).

I'm philosophically in favor of sharing this code. One of the biggest
benefits will be making review/audit easier. Another will be the
opportunities for more hardware acceleration.

But I can't tell if the library API as laid out here will be a good fit
for SunRPC and our kernel XDR implementation until I actually try to use
the API, which I don't have time for right now. The set of enctypes
indeed seems sufficient to support GSS-API Kerberos, and that is a
fundamental requirement for us.

The Linux in-kernel SMB community might be interested in sharing some of
this too, though they seem to have grown their own enctypes. The Cc list
on the thread is already substantial, but they should be included.

I think it would be fine to merge this, as long as the crypto folks are
happy with it, with its current single consumer (RxRPC), and then we can
explore broader sharing.


> Apart from that, things are much as they were previously from the point of
> view of someone using the API.  There's a new pair of functions that, given
> an encoding type, a key and a usage value, will derive the necessary keys
> and return an AEAD or hash handle.  These handles can then be passed to
> operation functions that will do the actual work of performing an
> encryption, a decryption, MIC generation or MIC verification.
> 
> Querying functions are also available to look up an encoding type table by
> kerberos protocol number and to help manage message layout.
> 
> This library has its own self-testing framework that checks more things
> than is possible with the testmgr, including subkey derivation.  It also
> checks things about the output of encrypt + decrypt that testmgr doesn't.
> That said, testmgr is also provisioned with some encryption and
> checksumming tests for Camilla and AES2, though these have to be
> provisioned with the intermediate subkeys rather than the transport key.
> 
> Note that, for purposes of illustration, I've included some rxrpc patches
> that use this interface to implement the rxgk Rx security class.  The
> branch also is based on net-next that carries some rxrpc patches that are a
> prerequisite for this, but the crypto patches don't need it.
> 
> ---
> The patches can be found here also:
> 
> 	http://git.kernel.org/cgit/linux/kernel/git/dhowells/linux-fs.git/log/?h=crypto-krb5
> 
> David
> 
> David Howells (24):
>    crypto/krb5: Add API Documentation
>    crypto/krb5: Add some constants out of sunrpc headers
>    crypto: Add 'krb5enc' hash and cipher AEAD algorithm
>    crypto/krb5: Test manager data
>    crypto/krb5: Implement Kerberos crypto core
>    crypto/krb5: Add an API to query the layout of the crypto section
>    crypto/krb5: Add an API to alloc and prepare a crypto object
>    crypto/krb5: Add an API to perform requests
>    crypto/krb5: Provide infrastructure and key derivation
>    crypto/krb5: Implement the Kerberos5 rfc3961 key derivation
>    crypto/krb5: Provide RFC3961 setkey packaging functions
>    crypto/krb5: Implement the Kerberos5 rfc3961 encrypt and decrypt
>      functions
>    crypto/krb5: Implement the Kerberos5 rfc3961 get_mic and verify_mic
>    crypto/krb5: Implement the AES enctypes from rfc3962
>    crypto/krb5: Implement the AES enctypes from rfc8009
>    crypto/krb5: Implement the AES encrypt/decrypt from rfc8009
>    crypto/krb5: Implement crypto self-testing
>    crypto/krb5: Add the AES self-testing data from rfc8009
>    crypto/krb5: Implement the Camellia enctypes from rfc6803
>    rxrpc: Add the security index for yfs-rxgk
>    rxrpc: Add YFS RxGK (GSSAPI) security class
>    rxrpc: rxgk: Provide infrastructure and key derivation
>    rxrpc: rxgk: Implement the yfs-rxgk security class (GSSAPI)
>    rxrpc: rxgk: Implement connection rekeying
> 
>   Documentation/crypto/index.rst   |    1 +
>   Documentation/crypto/krb5.rst    |  262 +++++++
>   crypto/Kconfig                   |   13 +
>   crypto/Makefile                  |    3 +
>   crypto/krb5/Kconfig              |   26 +
>   crypto/krb5/Makefile             |   18 +
>   crypto/krb5/internal.h           |  257 +++++++
>   crypto/krb5/krb5_api.c           |  452 ++++++++++++
>   crypto/krb5/krb5_kdf.c           |  145 ++++
>   crypto/krb5/rfc3961_simplified.c |  791 ++++++++++++++++++++
>   crypto/krb5/rfc3962_aes.c        |  115 +++
>   crypto/krb5/rfc6803_camellia.c   |  237 ++++++
>   crypto/krb5/rfc8009_aes2.c       |  431 +++++++++++
>   crypto/krb5/selftest.c           |  544 ++++++++++++++
>   crypto/krb5/selftest_data.c      |  291 ++++++++
>   crypto/krb5enc.c                 |  491 +++++++++++++
>   crypto/testmgr.c                 |   16 +
>   crypto/testmgr.h                 |  401 ++++++++++
>   fs/afs/misc.c                    |   13 +
>   include/crypto/krb5.h            |  167 +++++
>   include/keys/rxrpc-type.h        |   17 +
>   include/trace/events/rxrpc.h     |   36 +
>   include/uapi/linux/rxrpc.h       |   17 +
>   net/rxrpc/Kconfig                |   10 +
>   net/rxrpc/Makefile               |    5 +-
>   net/rxrpc/ar-internal.h          |   22 +
>   net/rxrpc/conn_event.c           |    2 +-
>   net/rxrpc/conn_object.c          |    1 +
>   net/rxrpc/key.c                  |  183 +++++
>   net/rxrpc/output.c               |    2 +-
>   net/rxrpc/protocol.h             |   20 +
>   net/rxrpc/rxgk.c                 | 1170 ++++++++++++++++++++++++++++++
>   net/rxrpc/rxgk_app.c             |  284 ++++++++
>   net/rxrpc/rxgk_common.h          |  140 ++++
>   net/rxrpc/rxgk_kdf.c             |  287 ++++++++
>   net/rxrpc/rxkad.c                |    6 +-
>   net/rxrpc/security.c             |    3 +
>   37 files changed, 6874 insertions(+), 5 deletions(-)
>   create mode 100644 Documentation/crypto/krb5.rst
>   create mode 100644 crypto/krb5/Kconfig
>   create mode 100644 crypto/krb5/Makefile
>   create mode 100644 crypto/krb5/internal.h
>   create mode 100644 crypto/krb5/krb5_api.c
>   create mode 100644 crypto/krb5/krb5_kdf.c
>   create mode 100644 crypto/krb5/rfc3961_simplified.c
>   create mode 100644 crypto/krb5/rfc3962_aes.c
>   create mode 100644 crypto/krb5/rfc6803_camellia.c
>   create mode 100644 crypto/krb5/rfc8009_aes2.c
>   create mode 100644 crypto/krb5/selftest.c
>   create mode 100644 crypto/krb5/selftest_data.c
>   create mode 100644 crypto/krb5enc.c
>   create mode 100644 include/crypto/krb5.h
>   create mode 100644 net/rxrpc/rxgk.c
>   create mode 100644 net/rxrpc/rxgk_app.c
>   create mode 100644 net/rxrpc/rxgk_common.h
>   create mode 100644 net/rxrpc/rxgk_kdf.c
> 


-- 
Chuck Lever