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

David Howells
2025-01-17T18:37:16Z

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,
+};