[PATCHv6 0/8] nvme: implement secure concatenation

[PATCHv6 0/8] nvme: implement secure concatenation

[Hannes Reinecke]

Hi all,

here's my attempt to implement secure concatenation for NVMe-of TCP
as outlined in TP8018.
The original (v5) patchset had been split in two, and this is the
second part based on top of the patchset 'nvme: fixes for secure
concatenation' sent earlier to the mailinglist.

Secure concatenation means that a TLS PSK is generated from the key
material negotiated by the DH-HMAC-CHAP protocol, and the TLS PSK
is then used for a subsequent TLS connection.
The difference between the original definition of secure concatenation
and the method outlined in TP8018 is that with TP8018 the connection
is reset after DH-HMAC-CHAP negotiation, and a new connection is setup
with the generated TLS PSK.

To implement that Sagi came up with the idea to directly reset the
admin queue once the DH-CHAP negotiation has completed; that way
it will be transparent to the upper layers and we don't have to
worry about exposing queues which should not be used.

As usual, comments and reviews are welcome.

Patchset can be found at
git.kernel.org:/pub/scm/linux/kernel/git/hare/nvme.git
branch secure-concat.v6

Changes to v5:
- Include reviews from Sagi
- Split patchset in two parts

Changes to v4:
- Rework reset admin queue functionality based on an idea
  from Sagi (thanks!)
- kbuild robot fixes
- Fixup dhchap negotiation with non-empty C2 value

Changes to v3:
- Include reviews from Sagi
- Do not start I/O queues after DH-HMAC-CHAP negotiation
- Use bool to indicate TLS has been enabled on a queue
- Add 'tls_keyring' sysfs attribute
- Add 'tls_configured_key' sysfs attribute

Changes to v2:
- Fixup reset after dhchap negotiation
- Disable namespace scanning on I/O queues after
  dhchap negotiation
      - Reworked TLS key handling (again)

Changes to the original submission:
- Sanitize TLS key handling
- Fixup modconfig compilation

Hannes Reinecke (8):
  crypto,fs: Separate out hkdf_extract() and hkdf_expand()
  nvme: add nvme_auth_generate_psk()
  nvme: add nvme_auth_generate_digest()
  nvme: add nvme_auth_derive_tls_psk()
  nvme-keyring: add nvme_tls_psk_refresh()
  nvme-tcp: request secure channel concatenation
  nvme-fabrics: reset admin connection for secure concatenation
  nvmet-tcp: support secure channel concatenation

 crypto/Makefile                        |   1 +
 crypto/hkdf.c                          | 112 +++++++++
 drivers/nvme/common/auth.c             | 303 +++++++++++++++++++++++++
 drivers/nvme/common/keyring.c          |  50 ++++
 drivers/nvme/host/auth.c               | 100 +++++++-
 drivers/nvme/host/fabrics.c            |  34 ++-
 drivers/nvme/host/fabrics.h            |   3 +
 drivers/nvme/host/tcp.c                |  65 +++++-
 drivers/nvme/target/auth.c             |  72 +++++-
 drivers/nvme/target/fabrics-cmd-auth.c |  49 +++-
 drivers/nvme/target/fabrics-cmd.c      |  26 ++-
 drivers/nvme/target/nvmet.h            |  38 +++-
 drivers/nvme/target/tcp.c              |  23 +-
 fs/crypto/hkdf.c                       |  68 +-----
 include/crypto/hkdf.h                  |  18 ++
 include/linux/nvme-auth.h              |   7 +
 include/linux/nvme-keyring.h           |   7 +
 include/linux/nvme.h                   |   7 +
 18 files changed, 889 insertions(+), 94 deletions(-)
 create mode 100644 crypto/hkdf.c
 create mode 100644 include/crypto/hkdf.h

-- 
2.35.3

[PATCH 1/8] crypto,fs: Separate out hkdf_extract() and hkdf_expand()

[Hannes Reinecke]

Separate out the HKDF functions into a separate file to make them
available to other callers.

Cc: Eric Biggers <ebiggers@kernel.org>
Cc: linux-crypto@vger.kernel.org
Signed-off-by: Hannes Reinecke <hare@kernel.org>
---
 crypto/Makefile       |   1 +
 crypto/hkdf.c         | 112 ++++++++++++++++++++++++++++++++++++++++++
 fs/crypto/hkdf.c      |  68 ++++---------------------
 include/crypto/hkdf.h |  18 +++++++
 4 files changed, 140 insertions(+), 59 deletions(-)
 create mode 100644 crypto/hkdf.c
 create mode 100644 include/crypto/hkdf.h

diff --git a/crypto/Makefile b/crypto/Makefile
index edbbaa3ffef5..b77fc360f0ff 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_CRYPTO_ECHAINIV) += echainiv.o
 
 crypto_hash-y += ahash.o
 crypto_hash-y += shash.o
+crypto_hash-y += hkdf.o
 obj-$(CONFIG_CRYPTO_HASH2) += crypto_hash.o
 
 obj-$(CONFIG_CRYPTO_AKCIPHER2) += akcipher.o
diff --git a/crypto/hkdf.c b/crypto/hkdf.c
new file mode 100644
index 000000000000..22e343851c0b
--- /dev/null
+++ b/crypto/hkdf.c
@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Implementation of HKDF ("HMAC-based Extract-and-Expand Key Derivation
+ * Function"), aka RFC 5869.  See also the original paper (Krawczyk 2010):
+ * "Cryptographic Extraction and Key Derivation: The HKDF Scheme".
+ *
+ * This is used to derive keys from the fscrypt master keys.
+ *
+ * Copyright 2019 Google LLC
+ */
+
+#include <crypto/hash.h>
+#include <crypto/sha2.h>
+#include <crypto/hkdf.h>
+
+/*
+ * HKDF consists of two steps:
+ *
+ * 1. HKDF-Extract: extract a pseudorandom key of length HKDF_HASHLEN bytes from
+ *    the input keying material and optional salt.
+ * 2. HKDF-Expand: expand the pseudorandom key into output keying material of
+ *    any length, parameterized by an application-specific info string.
+ *
+ */
+
+/* HKDF-Extract (RFC 5869 section 2.2), unsalted */
+int hkdf_extract(struct crypto_shash *hmac_tfm, const u8 *ikm,
+		 unsigned int ikmlen, u8 *prk)
+{
+	unsigned int prklen = crypto_shash_digestsize(hmac_tfm);
+	u8 *default_salt;
+	int err;
+
+	default_salt = kzalloc(prklen, GFP_KERNEL);
+	if (!default_salt)
+		return -ENOMEM;
+	err = crypto_shash_setkey(hmac_tfm, default_salt, prklen);
+	if (!err)
+		err = crypto_shash_tfm_digest(hmac_tfm, ikm, ikmlen, prk);
+
+	kfree(default_salt);
+	return err;
+}
+EXPORT_SYMBOL_GPL(hkdf_extract);
+
+/*
+ * HKDF-Expand (RFC 5869 section 2.3).
+ * This expands the pseudorandom key, which was already keyed into @hmac_tfm,
+ * into @okmlen bytes of output keying material parameterized by the
+ * application-specific @info of length @infolen bytes.
+ * This is thread-safe and may be called by multiple threads in parallel.
+ */
+int hkdf_expand(struct crypto_shash *hmac_tfm,
+		const u8 *info, unsigned int infolen,
+		u8 *okm, unsigned int okmlen)
+{
+	SHASH_DESC_ON_STACK(desc, hmac_tfm);
+	unsigned int i, hashlen = crypto_shash_digestsize(hmac_tfm);
+	int err;
+	const u8 *prev = NULL;
+	u8 counter = 1;
+	u8 *tmp;
+
+	if (WARN_ON(okmlen > 255 * hashlen))
+		return -EINVAL;
+
+	tmp = kzalloc(hashlen, GFP_KERNEL);
+	if (!tmp)
+		return -ENOMEM;
+
+	desc->tfm = hmac_tfm;
+
+	for (i = 0; i < okmlen; i += hashlen) {
+
+		err = crypto_shash_init(desc);
+		if (err)
+			goto out;
+
+		if (prev) {
+			err = crypto_shash_update(desc, prev, hashlen);
+			if (err)
+				goto out;
+		}
+
+		err = crypto_shash_update(desc, info, infolen);
+		if (err)
+			goto out;
+
+		BUILD_BUG_ON(sizeof(counter) != 1);
+		if (okmlen - i < hashlen) {
+			err = crypto_shash_finup(desc, &counter, 1, tmp);
+			if (err)
+				goto out;
+			memcpy(&okm[i], tmp, okmlen - i);
+			memzero_explicit(tmp, sizeof(tmp));
+		} else {
+			err = crypto_shash_finup(desc, &counter, 1, &okm[i]);
+			if (err)
+				goto out;
+		}
+		counter++;
+		prev = &okm[i];
+	}
+	err = 0;
+out:
+	if (unlikely(err))
+		memzero_explicit(okm, okmlen); /* so caller doesn't need to */
+	shash_desc_zero(desc);
+	kfree(tmp);
+	return err;
+}
+EXPORT_SYMBOL_GPL(hkdf_expand);
diff --git a/fs/crypto/hkdf.c b/fs/crypto/hkdf.c
index 5a384dad2c72..9c2f9aca9412 100644
--- a/fs/crypto/hkdf.c
+++ b/fs/crypto/hkdf.c
@@ -11,6 +11,7 @@
 
 #include <crypto/hash.h>
 #include <crypto/sha2.h>
+#include <crypto/hkdf.h>
 
 #include "fscrypt_private.h"
 
@@ -44,20 +45,6 @@
  * there's no way to persist a random salt per master key from kernel mode.
  */
 
-/* HKDF-Extract (RFC 5869 section 2.2), unsalted */
-static int hkdf_extract(struct crypto_shash *hmac_tfm, const u8 *ikm,
-			unsigned int ikmlen, u8 prk[HKDF_HASHLEN])
-{
-	static const u8 default_salt[HKDF_HASHLEN];
-	int err;
-
-	err = crypto_shash_setkey(hmac_tfm, default_salt, HKDF_HASHLEN);
-	if (err)
-		return err;
-
-	return crypto_shash_tfm_digest(hmac_tfm, ikm, ikmlen, prk);
-}
-
 /*
  * Compute HKDF-Extract using the given master key as the input keying material,
  * and prepare an HMAC transform object keyed by the resulting pseudorandom key.
@@ -118,61 +105,24 @@ int fscrypt_hkdf_expand(const struct fscrypt_hkdf *hkdf, u8 context,
 			u8 *okm, unsigned int okmlen)
 {
 	SHASH_DESC_ON_STACK(desc, hkdf->hmac_tfm);
-	u8 prefix[9];
-	unsigned int i;
+	u8 *prefix;
 	int err;
-	const u8 *prev = NULL;
-	u8 counter = 1;
-	u8 tmp[HKDF_HASHLEN];
 
 	if (WARN_ON_ONCE(okmlen > 255 * HKDF_HASHLEN))
 		return -EINVAL;
 
+	prefix = kzalloc(okmlen + 9, GFP_KERNEL);
+	if (!prefix)
+		return -ENOMEM;
 	desc->tfm = hkdf->hmac_tfm;
 
 	memcpy(prefix, "fscrypt\0", 8);
 	prefix[8] = context;
+	memcpy(prefix + 9, info, infolen);
 
-	for (i = 0; i < okmlen; i += HKDF_HASHLEN) {
-
-		err = crypto_shash_init(desc);
-		if (err)
-			goto out;
-
-		if (prev) {
-			err = crypto_shash_update(desc, prev, HKDF_HASHLEN);
-			if (err)
-				goto out;
-		}
-
-		err = crypto_shash_update(desc, prefix, sizeof(prefix));
-		if (err)
-			goto out;
-
-		err = crypto_shash_update(desc, info, infolen);
-		if (err)
-			goto out;
-
-		BUILD_BUG_ON(sizeof(counter) != 1);
-		if (okmlen - i < HKDF_HASHLEN) {
-			err = crypto_shash_finup(desc, &counter, 1, tmp);
-			if (err)
-				goto out;
-			memcpy(&okm[i], tmp, okmlen - i);
-			memzero_explicit(tmp, sizeof(tmp));
-		} else {
-			err = crypto_shash_finup(desc, &counter, 1, &okm[i]);
-			if (err)
-				goto out;
-		}
-		counter++;
-		prev = &okm[i];
-	}
-	err = 0;
-out:
-	if (unlikely(err))
-		memzero_explicit(okm, okmlen); /* so caller doesn't need to */
-	shash_desc_zero(desc);
+	err = hkdf_expand(hkdf->hmac_tfm, prefix, infolen + 8,
+			  okm, okmlen);
+	kfree(prefix);
 	return err;
 }
 
diff --git a/include/crypto/hkdf.h b/include/crypto/hkdf.h
new file mode 100644
index 000000000000..bf06c080d7ed
--- /dev/null
+++ b/include/crypto/hkdf.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * HKDF: HMAC-based Key Derivation Function (HKDF), RFC 5869
+ *
+ * Extracted from fs/crypto/hkdf.c, which has
+ * Copyright 2019 Google LLC
+ */
+
+#ifndef _CRYPTO_HKDF_H
+#define _CRYPTO_HKDF_H
+
+int hkdf_extract(struct crypto_shash *hmac_tfm, const u8 *ikm,
+		 unsigned int ikmlen, u8 *prk);
+int hkdf_expand(struct crypto_shash *hmac_tfm,
+		const u8 *info, unsigned int infolen,
+		u8 *okm, unsigned int okmlen);
+
+#endif
-- 
2.35.3

[PATCH 2/8] nvme: add nvme_auth_generate_psk()

[Hannes Reinecke]

Add a function to generate a NVMe PSK from the shared credentials
negotiated by DH-HMAC-CHAP.

Signed-off-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
---
 drivers/nvme/common/auth.c | 87 ++++++++++++++++++++++++++++++++++++++
 include/linux/nvme-auth.h  |  3 ++
 2 files changed, 90 insertions(+)

diff --git a/drivers/nvme/common/auth.c b/drivers/nvme/common/auth.c
index a3455f1d67fa..f6d21960b140 100644
--- a/drivers/nvme/common/auth.c
+++ b/drivers/nvme/common/auth.c
@@ -11,6 +11,7 @@
 #include <asm/unaligned.h>
 #include <crypto/hash.h>
 #include <crypto/dh.h>
+#include <crypto/hkdf.h>
 #include <linux/nvme.h>
 #include <linux/nvme-auth.h>
 
@@ -471,5 +472,91 @@ int nvme_auth_generate_key(u8 *secret, struct nvme_dhchap_key **ret_key)
 }
 EXPORT_SYMBOL_GPL(nvme_auth_generate_key);
 
+/*
+ * nvme_auth_generate_psk - Generate a PSK for TLS
+ *
+ * Generate a PSK for TLS as specified in NVMe base specification, section 8.13.5.9:
+ *    Generated PSK for TLS
+ *
+ * The generated PSK for TLS shall be computed applying the HMAC function using the
+ * hash function H( ) selected by the HashID parameter in the DH-HMAC-CHAP_Challenge
+ * message with the session key KS as key to the concatenation of the two challenges
+ * C1 and C2 (i.e., generated PSK = HMAC(KS, C1 || C2)).
+ */
+int nvme_auth_generate_psk(u8 hmac_id, u8 *skey, size_t skey_len,
+		u8 *c1, u8 *c2, size_t hash_len, u8 **ret_psk,size_t *ret_len)
+{
+	struct crypto_shash *tfm;
+	struct shash_desc *shash;
+	u8 *psk;
+	const char *hmac_name;
+	int ret, psk_len;
+
+	if (!c1 || !c2) {
+		pr_warn("%s: invalid parameter\n", __func__);
+		return -EINVAL;
+	}
+
+	hmac_name = nvme_auth_hmac_name(hmac_id);
+	if (!hmac_name) {
+		pr_warn("%s: invalid hash algoritm %d\n",
+			__func__, hmac_id);
+		return -EINVAL;
+	}
+
+	tfm = crypto_alloc_shash(hmac_name, 0, 0);
+	if (IS_ERR(tfm))
+		return PTR_ERR(tfm);
+
+	psk_len = crypto_shash_digestsize(tfm);
+	psk = kzalloc(psk_len, GFP_KERNEL);
+	if (!psk) {
+		ret = -ENOMEM;
+		goto out_free_tfm;
+	}
+
+	shash = kmalloc(sizeof(struct shash_desc) +
+			crypto_shash_descsize(tfm),
+			GFP_KERNEL);
+	if (!shash) {
+		ret = -ENOMEM;
+		goto out_free_psk;
+	}
+
+	shash->tfm = tfm;
+	ret = crypto_shash_setkey(tfm, skey, skey_len);
+	if (ret)
+		goto out_free_shash;
+
+	ret = crypto_shash_init(shash);
+	if (ret)
+		goto out_free_shash;
+
+	ret = crypto_shash_update(shash, c1, hash_len);
+	if (ret)
+		goto out_free_shash;
+
+	ret = crypto_shash_update(shash, c2, hash_len);
+	if (ret)
+		goto out_free_shash;
+
+	ret = crypto_shash_final(shash, psk);
+	if (!ret) {
+		*ret_psk = psk;
+		*ret_len = psk_len;
+	}
+
+out_free_shash:
+	kfree_sensitive(shash);
+out_free_psk:
+	if (ret)
+		kfree_sensitive(psk);
+out_free_tfm:
+	crypto_free_shash(tfm);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvme_auth_generate_psk);
+
 MODULE_DESCRIPTION("NVMe Authentication framework");
 MODULE_LICENSE("GPL v2");
diff --git a/include/linux/nvme-auth.h b/include/linux/nvme-auth.h
index c1d0bc5d9624..b13884b04dfd 100644
--- a/include/linux/nvme-auth.h
+++ b/include/linux/nvme-auth.h
@@ -40,5 +40,8 @@ int nvme_auth_gen_pubkey(struct crypto_kpp *dh_tfm,
 int nvme_auth_gen_shared_secret(struct crypto_kpp *dh_tfm,
 				u8 *ctrl_key, size_t ctrl_key_len,
 				u8 *sess_key, size_t sess_key_len);
+int nvme_auth_generate_psk(u8 hmac_id, u8 *skey, size_t skey_len,
+			   u8 *c1, u8 *c2, size_t hash_len,
+			   u8 **ret_psk, size_t *ret_len);
 
 #endif /* _NVME_AUTH_H */
-- 
2.35.3

[PATCH 3/8] nvme: add nvme_auth_generate_digest()

[Hannes Reinecke]

Add a function to calculate the PSK digest as specified in TP8018.

Signed-off-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
---
 drivers/nvme/common/auth.c | 126 +++++++++++++++++++++++++++++++++++++
 include/linux/nvme-auth.h  |   2 +
 2 files changed, 128 insertions(+)

diff --git a/drivers/nvme/common/auth.c b/drivers/nvme/common/auth.c
index f6d21960b140..7e40f205d3e4 100644
--- a/drivers/nvme/common/auth.c
+++ b/drivers/nvme/common/auth.c
@@ -558,5 +558,131 @@ int nvme_auth_generate_psk(u8 hmac_id, u8 *skey, size_t skey_len,
 }
 EXPORT_SYMBOL_GPL(nvme_auth_generate_psk);
 
+/*
+ * Generate a TLS PSK digest as specified in TP8018 Section 3.6.1.3:
+ *   TLS PSK and PSK identity Derivation
+ *
+ * The PSK digest shall be computed by encoding in Base64 (refer to RFC 4648)
+ * the result of the application of the HMAC function using the hash function
+ * specified in item 4 above (ie the hash function of the cipher suite associated
+ * with the PSK identity) with the PSK as HMAC key to the concatenation of:
+ * - the NQN of the host (i.e., NQNh) not including the null terminator;
+ * - a space character;
+ * - the NQN of the NVM subsystem (i.e., NQNc) not including the null terminator;
+ * - a space character; and
+ * - the seventeen ASCII characters "NVMe-over-Fabrics"
+ * (i.e., <PSK digest> = Base64(HMAC(PSK, NQNh || " " || NQNc || " " || "NVMe-over-Fabrics"))).
+ * The length of the PSK digest depends on the hash function used to compute
+ * it as follows:
+ * - If the SHA-256 hash function is used, the resulting PSK digest is 44 characters long; or
+ * - If the SHA-384 hash function is used, the resulting PSK digest is 64 characters long.
+ */
+int nvme_auth_generate_digest(u8 hmac_id, u8 *psk, size_t psk_len,
+		char *subsysnqn, char *hostnqn, u8 **ret_digest)
+{
+	struct crypto_shash *tfm;
+	struct shash_desc *shash;
+	u8 *digest, *hmac;
+	const char *hmac_name;
+	size_t digest_len, hmac_len;
+	int ret;
+
+	if (WARN_ON(!subsysnqn || !hostnqn))
+		return -EINVAL;
+
+	hmac_name = nvme_auth_hmac_name(hmac_id);
+	if (!hmac_name) {
+		pr_warn("%s: invalid hash algoritm %d\n",
+			__func__, hmac_id);
+		return -EINVAL;
+	}
+
+	switch (nvme_auth_hmac_hash_len(hmac_id)) {
+	case 32:
+		hmac_len = 44;
+		break;
+	case 48:
+		hmac_len = 64;
+		break;
+	default:
+		pr_warn("%s: invalid hash algorithm '%s'\n",
+			__func__, hmac_name);
+		return -EINVAL;
+	}
+
+	hmac = kzalloc(hmac_len + 1, GFP_KERNEL);
+	if (!hmac)
+		return -ENOMEM;
+
+	tfm = crypto_alloc_shash(hmac_name, 0, 0);
+	if (IS_ERR(tfm)) {
+		ret = PTR_ERR(tfm);
+		goto out_free_hmac;
+	}
+
+	digest_len = crypto_shash_digestsize(tfm);
+	digest = kzalloc(digest_len, GFP_KERNEL);
+	if (!digest) {
+		ret = -ENOMEM;
+		goto out_free_tfm;
+	}
+
+	shash = kmalloc(sizeof(struct shash_desc) +
+			crypto_shash_descsize(tfm),
+			GFP_KERNEL);
+	if (!shash) {
+		ret = -ENOMEM;
+		goto out_free_digest;
+	}
+
+	shash->tfm = tfm;
+	ret = crypto_shash_setkey(tfm, psk, psk_len);
+	if (ret)
+		goto out_free_shash;
+
+	ret = crypto_shash_init(shash);
+	if (ret)
+		goto out_free_shash;
+
+	ret = crypto_shash_update(shash, hostnqn, strlen(hostnqn));
+	if (ret)
+		goto out_free_shash;
+
+	ret = crypto_shash_update(shash, " ", 1);
+	if (ret)
+		goto out_free_shash;
+
+	ret = crypto_shash_update(shash, subsysnqn, strlen(subsysnqn));
+	if (ret)
+		goto out_free_shash;
+
+	ret = crypto_shash_update(shash, " NVMe-over-Fabrics", 18);
+	if (ret)
+		goto out_free_shash;
+
+	ret = crypto_shash_final(shash, digest);
+	if (ret)
+		goto out_free_shash;
+
+	ret = base64_encode(digest, digest_len, hmac);
+	if (ret < hmac_len)
+		ret = -ENOKEY;
+	*ret_digest = hmac;
+	ret = 0;
+
+out_free_shash:
+	kfree_sensitive(shash);
+out_free_digest:
+	kfree_sensitive(digest);
+out_free_tfm:
+	crypto_free_shash(tfm);
+out_free_hmac:
+	if (ret)
+		kfree_sensitive(hmac);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvme_auth_generate_digest);
+
 MODULE_DESCRIPTION("NVMe Authentication framework");
 MODULE_LICENSE("GPL v2");
diff --git a/include/linux/nvme-auth.h b/include/linux/nvme-auth.h
index b13884b04dfd..998f06bf10fd 100644
--- a/include/linux/nvme-auth.h
+++ b/include/linux/nvme-auth.h
@@ -43,5 +43,7 @@ int nvme_auth_gen_shared_secret(struct crypto_kpp *dh_tfm,
 int nvme_auth_generate_psk(u8 hmac_id, u8 *skey, size_t skey_len,
 			   u8 *c1, u8 *c2, size_t hash_len,
 			   u8 **ret_psk, size_t *ret_len);
+int nvme_auth_generate_digest(u8 hmac_id, u8 *psk, size_t psk_len,
+		char *subsysnqn, char *hostnqn, u8 **ret_digest);
 
 #endif /* _NVME_AUTH_H */
-- 
2.35.3

[PATCH 4/8] nvme: add nvme_auth_derive_tls_psk()

[Hannes Reinecke]

Add a function to derive the TLS PSK as specified TP8018.

Signed-off-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
---
 drivers/nvme/common/auth.c | 90 ++++++++++++++++++++++++++++++++++++++
 include/linux/nvme-auth.h  |  2 +
 2 files changed, 92 insertions(+)

diff --git a/drivers/nvme/common/auth.c b/drivers/nvme/common/auth.c
index 7e40f205d3e4..0b000a562c0f 100644
--- a/drivers/nvme/common/auth.c
+++ b/drivers/nvme/common/auth.c
@@ -684,5 +684,95 @@ int nvme_auth_generate_digest(u8 hmac_id, u8 *psk, size_t psk_len,
 }
 EXPORT_SYMBOL_GPL(nvme_auth_generate_digest);
 
+/*
+ * Derive a TLS PSK as specified in TP8018 Section 3.6.1.3:
+ *   TLS PSK and PSK identity Derivation
+ *
+ * The TLS PSK shall be derived as follows from an input PSK
+ * (i.e., either a retained PSK or a generated PSK) and a PSK
+ * identity using the HKDF-Extract and HKDF-Expand-Label operations
+ * (refer to RFC 5869 and RFC 8446) where the hash function is the
+ * one specified by the hash specifier of the PSK identity:
+ * 1. PRK = HKDF-Extract(0, Input PSK); and
+ * 2. TLS PSK = HKDF-Expand-Label(PRK, "nvme-tls-psk", PskIdentityContext, L),
+ * where PskIdentityContext is the hash identifier indicated in
+ * the PSK identity concatenated to a space character and to the
+ * Base64 PSK digest (i.e., "<hash> <PSK digest>") and L is the
+ * output size in bytes of the hash function (i.e., 32 for SHA-256
+ * and 48 for SHA-384).
+ */
+int nvme_auth_derive_tls_psk(int hmac_id, u8 *psk, size_t psk_len,
+		u8 *psk_digest, u8 **ret_psk)
+{
+	struct crypto_shash *hmac_tfm;
+	const char *hmac_name;
+	const char *psk_prefix = "tls13 nvme-tls-psk";
+	size_t info_len, prk_len;
+	char *info;
+	unsigned char *prk, *tls_key;
+	int ret;
+
+	hmac_name = nvme_auth_hmac_name(hmac_id);
+	if (!hmac_name) {
+		pr_warn("%s: invalid hash algoritm %d\n",
+			__func__, hmac_id);
+		return -EINVAL;
+	}
+	if (hmac_id == NVME_AUTH_HASH_SHA512) {
+		pr_warn("%s: unsupported hash algorithm %s\n",
+			__func__, hmac_name);
+		return -EINVAL;
+	}
+
+	hmac_tfm = crypto_alloc_shash(hmac_name, 0, 0);
+	if (IS_ERR(hmac_tfm))
+		return PTR_ERR(hmac_tfm);
+
+	prk_len = crypto_shash_digestsize(hmac_tfm);
+	prk = kzalloc(prk_len, GFP_KERNEL);
+	if (!prk) {
+		ret = -ENOMEM;
+		goto out_free_shash;
+	}
+
+	ret = hkdf_extract(hmac_tfm, psk, psk_len, prk);
+	if (ret)
+		goto out_free_prk;
+
+	ret = crypto_shash_setkey(hmac_tfm, prk, prk_len);
+	if (ret)
+		goto out_free_prk;
+
+	info_len = strlen(psk_digest) + strlen(psk_prefix) + 1;
+	info = kzalloc(info_len, GFP_KERNEL);
+	if (!info)
+		goto out_free_prk;
+
+	memcpy(info, psk_prefix, strlen(psk_prefix));
+	memcpy(info + strlen(psk_prefix), psk_digest, strlen(psk_digest));
+
+	tls_key = kzalloc(psk_len, GFP_KERNEL);
+	if (!tls_key) {
+		ret = -ENOMEM;
+		goto out_free_info;
+	}
+	ret = hkdf_expand(hmac_tfm, info, strlen(info), tls_key, psk_len);
+	if (ret) {
+		kfree(tls_key);
+		goto out_free_info;
+	}
+	*ret_psk = tls_key;
+
+out_free_info:
+	kfree(info);
+out_free_prk:
+	kfree(prk);
+out_free_shash:
+	crypto_free_shash(hmac_tfm);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(nvme_auth_derive_tls_psk);
+
 MODULE_DESCRIPTION("NVMe Authentication framework");
 MODULE_LICENSE("GPL v2");
diff --git a/include/linux/nvme-auth.h b/include/linux/nvme-auth.h
index 998f06bf10fd..60e069a6757f 100644
--- a/include/linux/nvme-auth.h
+++ b/include/linux/nvme-auth.h
@@ -45,5 +45,7 @@ int nvme_auth_generate_psk(u8 hmac_id, u8 *skey, size_t skey_len,
 			   u8 **ret_psk, size_t *ret_len);
 int nvme_auth_generate_digest(u8 hmac_id, u8 *psk, size_t psk_len,
 		char *subsysnqn, char *hostnqn, u8 **ret_digest);
+int nvme_auth_derive_tls_psk(int hmac_id, u8 *psk, size_t psk_len,
+		u8 *psk_digest, u8 **ret_psk);
 
 #endif /* _NVME_AUTH_H */
-- 
2.35.3

[PATCH 5/8] nvme-keyring: add nvme_tls_psk_refresh()

[Hannes Reinecke]

Add a function to refresh a generated PSK in the specified keyring.

Signed-off-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
---
 drivers/nvme/common/keyring.c | 50 +++++++++++++++++++++++++++++++++++
 include/linux/nvme-keyring.h  |  7 +++++
 2 files changed, 57 insertions(+)

diff --git a/drivers/nvme/common/keyring.c b/drivers/nvme/common/keyring.c
index 5b886fd6c3e7..9e847c3ee820 100644
--- a/drivers/nvme/common/keyring.c
+++ b/drivers/nvme/common/keyring.c
@@ -123,6 +123,56 @@ static struct key *nvme_tls_psk_lookup(struct key *keyring,
 	return key_ref_to_ptr(keyref);
 }
 
+struct key *nvme_tls_psk_refresh(struct key *keyring, char *hostnqn, char *subnqn,
+		u8 hmac_id, bool generated, u8 *data, size_t data_len, char *digest)
+{
+	key_perm_t keyperm =
+		KEY_POS_SEARCH | KEY_POS_VIEW | KEY_POS_READ |
+		KEY_POS_WRITE | KEY_POS_LINK | KEY_POS_SETATTR |
+		KEY_USR_SEARCH | KEY_USR_VIEW | KEY_USR_READ;
+	char *identity;
+	size_t identity_len = (NVMF_NQN_SIZE) * 2 + 77;
+	key_ref_t keyref;
+	key_serial_t keyring_id;
+	struct key *key;
+
+	if (!hostnqn || !subnqn || !data || !data_len)
+		return ERR_PTR(-EINVAL);
+
+	identity = kzalloc(identity_len, GFP_KERNEL);
+	if (!identity)
+		return ERR_PTR(-ENOMEM);
+
+	snprintf(identity, identity_len, "NVMe1%c%02d %s %s %s",
+		 generated ? 'G' : 'R', hmac_id, hostnqn, subnqn, digest);
+
+	if (!keyring)
+		keyring = nvme_keyring;
+	keyring_id = key_serial(keyring);
+	pr_debug("keyring %x refresh tls psk '%s'\n",
+		 keyring_id, identity);
+	keyref = key_create_or_update(make_key_ref(keyring, true),
+				"psk", identity, data, data_len,
+				keyperm, KEY_ALLOC_NOT_IN_QUOTA |
+				      KEY_ALLOC_BUILT_IN |
+				      KEY_ALLOC_BYPASS_RESTRICTION);
+	if (IS_ERR(keyref)) {
+		pr_debug("refresh tls psk '%s' failed, error %ld\n",
+			 identity, PTR_ERR(keyref));
+		kfree(identity);
+		return ERR_PTR(-ENOKEY);
+	}
+	kfree(identity);
+	/*
+	 * Set the default timeout to 1 hour
+	 * as suggested in TP8018.
+	 */
+	key = key_ref_to_ptr(keyref);
+	key_set_timeout(key, 3600);
+	return key;
+}
+EXPORT_SYMBOL_GPL(nvme_tls_psk_refresh);
+
 /*
  * NVMe PSK priority list
  *
diff --git a/include/linux/nvme-keyring.h b/include/linux/nvme-keyring.h
index e092e3e6ffb2..65400c89bde5 100644
--- a/include/linux/nvme-keyring.h
+++ b/include/linux/nvme-keyring.h
@@ -8,6 +8,8 @@
 
 #if IS_ENABLED(CONFIG_NVME_KEYRING)
 
+struct key *nvme_tls_psk_refresh(struct key *keyring, char *hostnqn, char *subnqn,
+				 u8 hmac_id, bool generated, u8 *data, size_t data_len, char *digest);
 key_serial_t nvme_tls_psk_default(struct key *keyring,
 		const char *hostnqn, const char *subnqn);
 
@@ -15,6 +17,11 @@ key_serial_t nvme_keyring_id(void);
 struct key *nvme_tls_key_lookup(key_serial_t key_id);
 #else
 
+static struct key *nvme_tls_psk_refresh(struct key *keyring, char *hostnqn, char *subnqn,
+		u8 hmac_id, bool generated, u8 *data, size_t data_len, char *digest)
+{
+	return ERR_PTR(-ENOTSUPP);
+}
 static inline key_serial_t nvme_tls_psk_default(struct key *keyring,
 		const char *hostnqn, const char *subnqn)
 {
-- 
2.35.3

[PATCH 6/8] nvme-tcp: request secure channel concatenation

[Hannes Reinecke]

Add a fabrics option 'concat' to request secure channel concatenation.
When secure channel concatenation is enabled a 'generated PSK' is inserted
into the keyring such that it's available after reset.

Signed-off-by: Hannes Reinecke <hare@kernel.org>
---
 drivers/nvme/host/auth.c    | 100 ++++++++++++++++++++++++++++++++++--
 drivers/nvme/host/fabrics.c |  34 ++++++++++--
 drivers/nvme/host/fabrics.h |   3 ++
 drivers/nvme/host/tcp.c     |  56 +++++++++++++++++---
 include/linux/nvme.h        |   7 +++
 5 files changed, 188 insertions(+), 12 deletions(-)

diff --git a/drivers/nvme/host/auth.c b/drivers/nvme/host/auth.c
index 371e14f0a203..5f71aa7b5e27 100644
--- a/drivers/nvme/host/auth.c
+++ b/drivers/nvme/host/auth.c
@@ -12,6 +12,7 @@
 #include "nvme.h"
 #include "fabrics.h"
 #include <linux/nvme-auth.h>
+#include <linux/nvme-keyring.h>
 
 #define CHAP_BUF_SIZE 4096
 static struct kmem_cache *nvme_chap_buf_cache;
@@ -131,7 +132,12 @@ static int nvme_auth_set_dhchap_negotiate_data(struct nvme_ctrl *ctrl,
 	data->auth_type = NVME_AUTH_COMMON_MESSAGES;
 	data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_NEGOTIATE;
 	data->t_id = cpu_to_le16(chap->transaction);
-	data->sc_c = 0; /* No secure channel concatenation */
+	if (!ctrl->opts->concat || chap->qid != 0)
+		data->sc_c = NVME_AUTH_SECP_NOSC;
+	else if (ctrl->opts->tls_key)
+		data->sc_c = NVME_AUTH_SECP_REPLACETLSPSK;
+	else
+		data->sc_c = NVME_AUTH_SECP_NEWTLSPSK;
 	data->napd = 1;
 	data->auth_protocol[0].dhchap.authid = NVME_AUTH_DHCHAP_AUTH_ID;
 	data->auth_protocol[0].dhchap.halen = 3;
@@ -311,8 +317,9 @@ static int nvme_auth_set_dhchap_reply_data(struct nvme_ctrl *ctrl,
 	data->hl = chap->hash_len;
 	data->dhvlen = cpu_to_le16(chap->host_key_len);
 	memcpy(data->rval, chap->response, chap->hash_len);
-	if (ctrl->ctrl_key) {
+	if (ctrl->ctrl_key)
 		chap->bi_directional = true;
+	if (ctrl->ctrl_key || ctrl->opts->concat) {
 		get_random_bytes(chap->c2, chap->hash_len);
 		data->cvalid = 1;
 		memcpy(data->rval + chap->hash_len, chap->c2,
@@ -322,7 +329,10 @@ static int nvme_auth_set_dhchap_reply_data(struct nvme_ctrl *ctrl,
 	} else {
 		memset(chap->c2, 0, chap->hash_len);
 	}
-	chap->s2 = nvme_auth_get_seqnum();
+	if (ctrl->opts->concat)
+		chap->s2 = 0;
+	else
+		chap->s2 = nvme_auth_get_seqnum();
 	data->seqnum = cpu_to_le32(chap->s2);
 	if (chap->host_key_len) {
 		dev_dbg(ctrl->device, "%s: qid %d host public key %*ph\n",
@@ -677,6 +687,76 @@ static void nvme_auth_free_dhchap(struct nvme_dhchap_queue_context *chap)
 		crypto_free_kpp(chap->dh_tfm);
 }
 
+static int nvme_auth_secure_concat(struct nvme_ctrl *ctrl,
+				   struct nvme_dhchap_queue_context *chap)
+{
+	u8 *psk, *digest, *tls_psk;
+	struct key *tls_key;
+	size_t psk_len;
+	int ret = 0;
+
+	if (!chap->sess_key) {
+		dev_warn(ctrl->device,
+			 "%s: qid %d no session key negotiated\n",
+			 __func__, chap->qid);
+		return -ENOKEY;
+	}
+
+	ret = nvme_auth_generate_psk(chap->hash_id, chap->sess_key,
+				     chap->sess_key_len,
+				     chap->c1, chap->c2,
+				     chap->hash_len, &psk, &psk_len);
+	if (ret) {
+		dev_warn(ctrl->device,
+			 "%s: qid %d failed to generate PSK, error %d\n",
+			 __func__, chap->qid, ret);
+		return ret;
+	}
+	dev_dbg(ctrl->device,
+		  "%s: generated psk %*ph\n", __func__, (int)psk_len, psk);
+
+	ret = nvme_auth_generate_digest(chap->hash_id, psk, psk_len,
+					ctrl->opts->subsysnqn,
+					ctrl->opts->host->nqn, &digest);
+	if (ret) {
+		dev_warn(ctrl->device,
+			 "%s: qid %d failed to generate digest, error %d\n",
+			 __func__, chap->qid, ret);
+		goto out_free_psk;
+	};
+	dev_dbg(ctrl->device, "%s: generated digest %s\n",
+		 __func__, digest);
+	ret = nvme_auth_derive_tls_psk(chap->hash_id, psk, psk_len, digest, &tls_psk);
+	if (ret) {
+		dev_warn(ctrl->device,
+			 "%s: qid %d failed to derive TLS psk, error %d\n",
+			 __func__, chap->qid, ret);
+		goto out_free_digest;
+	};
+
+	tls_key = nvme_tls_psk_refresh(ctrl->opts->keyring, ctrl->opts->host->nqn,
+				       ctrl->opts->subsysnqn, chap->hash_id,
+				       true, tls_psk, psk_len, digest);
+	if (IS_ERR(tls_key)) {
+		ret = PTR_ERR(tls_key);
+		dev_warn(ctrl->device,
+			 "%s: qid %d failed to insert generated key, error %d\n",
+			 __func__, chap->qid, ret);
+		tls_key = NULL;
+		kfree_sensitive(tls_psk);
+	}
+	if (ctrl->opts->tls_key) {
+		key_revoke(ctrl->opts->tls_key);
+		key_put(ctrl->opts->tls_key);
+	}
+	ctrl->opts->tls_key = tls_key;
+out_free_digest:
+	kfree_sensitive(digest);
+out_free_psk:
+	kfree_sensitive(psk);
+	return ret;
+}
+
 static void nvme_queue_auth_work(struct work_struct *work)
 {
 	struct nvme_dhchap_queue_context *chap =
@@ -833,6 +913,14 @@ static void nvme_queue_auth_work(struct work_struct *work)
 	}
 	if (!ret) {
 		chap->error = 0;
+		/* Secure concatenation can only be enabled on the admin queue */
+		if (!chap->qid && ctrl->opts->concat &&
+		    (ret = nvme_auth_secure_concat(ctrl, chap))) {
+			dev_warn(ctrl->device,
+				 "%s: qid %d failed to enable secure concatenation\n",
+				 __func__, chap->qid);
+			chap->error = ret;
+		}
 		return;
 	}
 
@@ -912,6 +1000,12 @@ static void nvme_ctrl_auth_work(struct work_struct *work)
 			 "qid 0: authentication failed\n");
 		return;
 	}
+	/*
+	 * Only run authentication on the admin queue for
+	 * secure concatenation
+	 */
+	if (ctrl->opts->concat)
+		return;
 
 	for (q = 1; q < ctrl->queue_count; q++) {
 		ret = nvme_auth_negotiate(ctrl, q);
diff --git a/drivers/nvme/host/fabrics.c b/drivers/nvme/host/fabrics.c
index 432efcbf9e2f..93e9041b9657 100644
--- a/drivers/nvme/host/fabrics.c
+++ b/drivers/nvme/host/fabrics.c
@@ -472,8 +472,9 @@ int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl)
 	result = le32_to_cpu(res.u32);
 	ctrl->cntlid = result & 0xFFFF;
 	if (result & (NVME_CONNECT_AUTHREQ_ATR | NVME_CONNECT_AUTHREQ_ASCR)) {
-		/* Secure concatenation is not implemented */
-		if (result & NVME_CONNECT_AUTHREQ_ASCR) {
+		/* Check for secure concatenation */
+		if ((result & NVME_CONNECT_AUTHREQ_ASCR) &&
+		    !ctrl->opts->concat) {
 			dev_warn(ctrl->device,
 				 "qid 0: secure concatenation is not supported\n");
 			ret = -EOPNOTSUPP;
@@ -550,7 +551,7 @@ int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid)
 		/* Secure concatenation is not implemented */
 		if (result & NVME_CONNECT_AUTHREQ_ASCR) {
 			dev_warn(ctrl->device,
-				 "qid 0: secure concatenation is not supported\n");
+				 "qid %d: secure concatenation is not supported\n", qid);
 			ret = -EOPNOTSUPP;
 			goto out_free_data;
 		}
@@ -706,6 +707,7 @@ static const match_table_t opt_tokens = {
 #endif
 #ifdef CONFIG_NVME_TCP_TLS
 	{ NVMF_OPT_TLS,			"tls"			},
+	{ NVMF_OPT_CONCAT,		"concat"		},
 #endif
 	{ NVMF_OPT_ERR,			NULL			}
 };
@@ -735,6 +737,7 @@ static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
 	opts->tls = false;
 	opts->tls_key = NULL;
 	opts->keyring = NULL;
+	opts->concat = false;
 
 	options = o = kstrdup(buf, GFP_KERNEL);
 	if (!options)
@@ -1053,6 +1056,14 @@ static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
 			}
 			opts->tls = true;
 			break;
+		case NVMF_OPT_CONCAT:
+			if (!IS_ENABLED(CONFIG_NVME_TCP_TLS)) {
+				pr_err("TLS is not supported\n");
+				ret = -EINVAL;
+				goto out;
+			}
+			opts->concat = true;
+			break;
 		default:
 			pr_warn("unknown parameter or missing value '%s' in ctrl creation request\n",
 				p);
@@ -1079,6 +1090,23 @@ static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
 			pr_warn("failfast tmo (%d) larger than controller loss tmo (%d)\n",
 				opts->fast_io_fail_tmo, ctrl_loss_tmo);
 	}
+	if (opts->concat) {
+		if (opts->tls) {
+			pr_err("Secure concatenation over TLS is not supported\n");
+			ret = -EINVAL;
+			goto out;
+		}
+		if (opts->tls_key) {
+			pr_err("Cannot specify a TLS key for secure concatenation\n");
+			ret = -EINVAL;
+			goto out;
+		}
+		if (!opts->dhchap_secret) {
+			pr_err("Need to enable DH-CHAP for secure concatenation\n");
+			ret = -EINVAL;
+			goto out;
+		}
+	}
 
 	opts->host = nvmf_host_add(hostnqn, &hostid);
 	if (IS_ERR(opts->host)) {
diff --git a/drivers/nvme/host/fabrics.h b/drivers/nvme/host/fabrics.h
index 21d75dc4a3a0..9cf5b020adba 100644
--- a/drivers/nvme/host/fabrics.h
+++ b/drivers/nvme/host/fabrics.h
@@ -66,6 +66,7 @@ enum {
 	NVMF_OPT_TLS		= 1 << 25,
 	NVMF_OPT_KEYRING	= 1 << 26,
 	NVMF_OPT_TLS_KEY	= 1 << 27,
+	NVMF_OPT_CONCAT		= 1 << 28,
 };
 
 /**
@@ -101,6 +102,7 @@ enum {
  * @keyring:    Keyring to use for key lookups
  * @tls_key:    TLS key for encrypted connections (TCP)
  * @tls:        Start TLS encrypted connections (TCP)
+ * @concat:     Enabled Secure channel concatenation (TCP)
  * @disable_sqflow: disable controller sq flow control
  * @hdr_digest: generate/verify header digest (TCP)
  * @data_digest: generate/verify data digest (TCP)
@@ -130,6 +132,7 @@ struct nvmf_ctrl_options {
 	struct key		*keyring;
 	struct key		*tls_key;
 	bool			tls;
+	bool			concat;
 	bool			disable_sqflow;
 	bool			hdr_digest;
 	bool			data_digest;
diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
index 5885aa452aa1..b748e4033df2 100644
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -227,7 +227,7 @@ static inline bool nvme_tcp_tls_configured(struct nvme_ctrl *ctrl)
 	if (!IS_ENABLED(CONFIG_NVME_TCP_TLS))
 		return 0;
 
-	return ctrl->opts->tls;
+	return ctrl->opts->tls || ctrl->opts->concat;
 }
 
 static inline struct blk_mq_tags *nvme_tcp_tagset(struct nvme_tcp_queue *queue)
@@ -1942,7 +1942,7 @@ static int nvme_tcp_alloc_admin_queue(struct nvme_ctrl *ctrl)
 	if (nvme_tcp_tls_configured(ctrl)) {
 		if (ctrl->opts->tls_key)
 			pskid = key_serial(ctrl->opts->tls_key);
-		else {
+		else if (ctrl->opts->tls) {
 			pskid = nvme_tls_psk_default(ctrl->opts->keyring,
 						      ctrl->opts->host->nqn,
 						      ctrl->opts->subsysnqn);
@@ -1972,9 +1972,25 @@ static int __nvme_tcp_alloc_io_queues(struct nvme_ctrl *ctrl)
 {
 	int i, ret;
 
-	if (nvme_tcp_tls_configured(ctrl) && !ctrl->tls_pskid) {
-		dev_err(ctrl->device, "no PSK negotiated\n");
-		return -ENOKEY;
+	if (nvme_tcp_tls_configured(ctrl)) {
+		if (ctrl->opts->concat) {
+			/*
+			 * The generated PSK is stored in the
+			 * fabric options
+			 */
+			if (!ctrl->opts->tls_key) {
+				dev_err(ctrl->device, "no PSK generated\n");
+				return -ENOKEY;
+			}
+			if (ctrl->tls_pskid &&
+			    ctrl->tls_pskid != key_serial(ctrl->opts->tls_key)) {
+				dev_err(ctrl->device, "Stale PSK id %08x\n", ctrl->tls_pskid);
+				ctrl->tls_pskid = 0;
+			}
+		} else if (!ctrl->tls_pskid) {
+			dev_err(ctrl->device, "no PSK negotiated\n");
+			return -ENOKEY;
+		}
 	}
 
 	for (i = 1; i < ctrl->queue_count; i++) {
@@ -2205,6 +2221,30 @@ static void nvme_tcp_reconnect_or_remove(struct nvme_ctrl *ctrl,
 	}
 }
 
+/*
+ * The TLS key needs to be revoked when:
+ * - concatenation is enabled and
+ *   -> This is a generated key and only valid for this session
+ * - the generated key is present in ctrl->tls_key and
+ *   -> authentication has completed and the key has been generated
+ * - tls has been enabled
+ *   -> otherwise we are about to reset the admin queue after authentication
+ *      to enable TLS with the generated key
+ */
+static bool nvme_tcp_key_revoke_needed(struct nvme_ctrl *ctrl)
+{
+	return ctrl->opts->concat && ctrl->opts->tls_key && ctrl->tls_pskid;
+}
+
+static void nvme_tcp_revoke_tls_key(struct nvme_ctrl *ctrl)
+{
+	dev_dbg(ctrl->device, "Wipe generated TLS PSK %08x\n",
+		key_serial(ctrl->opts->tls_key));
+	key_revoke(ctrl->opts->tls_key);
+	key_put(ctrl->opts->tls_key);
+	ctrl->opts->tls_key = NULL;
+}
+
 static int nvme_tcp_setup_ctrl(struct nvme_ctrl *ctrl, bool new)
 {
 	struct nvmf_ctrl_options *opts = ctrl->opts;
@@ -2308,6 +2348,8 @@ static void nvme_tcp_error_recovery_work(struct work_struct *work)
 				struct nvme_tcp_ctrl, err_work);
 	struct nvme_ctrl *ctrl = &tcp_ctrl->ctrl;
 
+	if (nvme_tcp_key_revoke_needed(ctrl))
+		nvme_tcp_revoke_tls_key(ctrl);
 	nvme_stop_keep_alive(ctrl);
 	flush_work(&ctrl->async_event_work);
 	nvme_tcp_teardown_io_queues(ctrl, false);
@@ -2348,6 +2390,8 @@ static void nvme_reset_ctrl_work(struct work_struct *work)
 		container_of(work, struct nvme_ctrl, reset_work);
 	int ret;
 
+	if (nvme_tcp_key_revoke_needed(ctrl))
+		nvme_tcp_revoke_tls_key(ctrl);
 	nvme_stop_ctrl(ctrl);
 	nvme_tcp_teardown_ctrl(ctrl, false);
 
@@ -2842,7 +2886,7 @@ static struct nvmf_transport_ops nvme_tcp_transport = {
 			  NVMF_OPT_HDR_DIGEST | NVMF_OPT_DATA_DIGEST |
 			  NVMF_OPT_NR_WRITE_QUEUES | NVMF_OPT_NR_POLL_QUEUES |
 			  NVMF_OPT_TOS | NVMF_OPT_HOST_IFACE | NVMF_OPT_TLS |
-			  NVMF_OPT_KEYRING | NVMF_OPT_TLS_KEY,
+			  NVMF_OPT_KEYRING | NVMF_OPT_TLS_KEY | NVMF_OPT_CONCAT,
 	.create_ctrl	= nvme_tcp_create_ctrl,
 };
 
diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index 5c2290f0d5af..5626894d7700 100644
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -1676,6 +1676,13 @@ enum {
 	NVME_AUTH_DHGROUP_INVALID	= 0xff,
 };
 
+enum {
+	NVME_AUTH_SECP_NOSC		= 0x00,
+	NVME_AUTH_SECP_SC		= 0x01,
+	NVME_AUTH_SECP_NEWTLSPSK	= 0x02,
+	NVME_AUTH_SECP_REPLACETLSPSK	= 0x03,
+};
+
 union nvmf_auth_protocol {
 	struct nvmf_auth_dhchap_protocol_descriptor dhchap;
 };
-- 
2.35.3

[PATCH 7/8] nvme-fabrics: reset admin connection for secure concatenation

[Hannes Reinecke]

When secure concatenation is requested the connection needs to be
reset to enable TLS encryption on the new cnnection.
That implies that the original connection used for the DH-CHAP
negotiation really shouldn't be used, and we should reset as soon
as the DH-CHAP negotiation has succeeded on the admin queue.

Based on an idea from Sagi.

Signed-off-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
---
 drivers/nvme/host/tcp.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
index b748e4033df2..08ac764ebfb0 100644
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -2254,6 +2254,15 @@ static int nvme_tcp_setup_ctrl(struct nvme_ctrl *ctrl, bool new)
 	if (ret)
 		return ret;
 
+	if (new && ctrl->opts && ctrl->opts->concat && !ctrl->tls_pskid) {
+		dev_dbg(ctrl->device, "restart admin queue for secure concatenation\n");
+		nvme_stop_keep_alive(ctrl);
+		nvme_tcp_teardown_admin_queue(ctrl, false);
+		ret = nvme_tcp_configure_admin_queue(ctrl, false);
+		if (ret)
+			return ret;
+	}
+
 	if (ctrl->icdoff) {
 		ret = -EOPNOTSUPP;
 		dev_err(ctrl->device, "icdoff is not supported!\n");
-- 
2.35.3

[PATCH 8/8] nvmet-tcp: support secure channel concatenation

[Hannes Reinecke]

Evaluate the SC_C flag during DH-CHAP-HMAC negotiation and insert
the generated PSK once negotiation has finished.

Signed-off-by: Hannes Reinecke <hare@kernel.org>
---
 drivers/nvme/target/auth.c             | 72 +++++++++++++++++++++++++-
 drivers/nvme/target/fabrics-cmd-auth.c | 49 +++++++++++++++---
 drivers/nvme/target/fabrics-cmd.c      | 26 +++++++---
 drivers/nvme/target/nvmet.h            | 38 +++++++++++---
 drivers/nvme/target/tcp.c              | 23 +++++++-
 5 files changed, 185 insertions(+), 23 deletions(-)

diff --git a/drivers/nvme/target/auth.c b/drivers/nvme/target/auth.c
index 7897d02c681d..560321df5bf6 100644
--- a/drivers/nvme/target/auth.c
+++ b/drivers/nvme/target/auth.c
@@ -15,6 +15,7 @@
 #include <linux/ctype.h>
 #include <linux/random.h>
 #include <linux/nvme-auth.h>
+#include <linux/nvme-keyring.h>
 #include <asm/unaligned.h>
 
 #include "nvmet.h"
@@ -138,7 +139,7 @@ int nvmet_setup_dhgroup(struct nvmet_ctrl *ctrl, u8 dhgroup_id)
 	return ret;
 }
 
-u8 nvmet_setup_auth(struct nvmet_ctrl *ctrl)
+u8 nvmet_setup_auth(struct nvmet_ctrl *ctrl, struct nvmet_req *req)
 {
 	int ret = 0;
 	struct nvmet_host_link *p;
@@ -164,6 +165,11 @@ u8 nvmet_setup_auth(struct nvmet_ctrl *ctrl)
 		goto out_unlock;
 	}
 
+	if (nvmet_queue_tls_keyid(req->sq)) {
+		pr_debug("host %s tls enabled\n", ctrl->hostnqn);
+		goto out_unlock;
+	}
+
 	ret = nvmet_setup_dhgroup(ctrl, host->dhchap_dhgroup_id);
 	if (ret < 0) {
 		pr_warn("Failed to setup DH group");
@@ -232,6 +238,9 @@ u8 nvmet_setup_auth(struct nvmet_ctrl *ctrl)
 void nvmet_auth_sq_free(struct nvmet_sq *sq)
 {
 	cancel_delayed_work(&sq->auth_expired_work);
+#ifdef CONFIG_NVME_TARGET_TCP_TLS
+	sq->tls_key = 0;
+#endif
 	kfree(sq->dhchap_c1);
 	sq->dhchap_c1 = NULL;
 	kfree(sq->dhchap_c2);
@@ -260,6 +269,12 @@ void nvmet_destroy_auth(struct nvmet_ctrl *ctrl)
 		nvme_auth_free_key(ctrl->ctrl_key);
 		ctrl->ctrl_key = NULL;
 	}
+#ifdef CONFIG_NVME_TARGET_TCP_TLS
+	if (ctrl->tls_key) {
+		key_put(ctrl->tls_key);
+		ctrl->tls_key = NULL;
+	}
+#endif
 }
 
 bool nvmet_check_auth_status(struct nvmet_req *req)
@@ -541,3 +556,58 @@ int nvmet_auth_ctrl_sesskey(struct nvmet_req *req,
 
 	return ret;
 }
+
+void nvmet_auth_insert_psk(struct nvmet_sq *sq)
+{
+	int hash_len = nvme_auth_hmac_hash_len(sq->ctrl->shash_id);
+	u8 *psk, *digest, *tls_psk;
+	size_t psk_len;
+	int ret;
+#ifdef CONFIG_NVME_TARGET_TCP_TLS
+	struct key *tls_key = NULL;
+#endif
+
+	ret = nvme_auth_generate_psk(sq->ctrl->shash_id,
+				     sq->dhchap_skey,
+				     sq->dhchap_skey_len,
+				     sq->dhchap_c1, sq->dhchap_c2,
+				     hash_len, &psk, &psk_len);
+	if (ret) {
+		pr_warn("%s: ctrl %d qid %d failed to generate PSK, error %d\n",
+			__func__, sq->ctrl->cntlid, sq->qid, ret);
+		return;
+	}
+	ret = nvme_auth_generate_digest(sq->ctrl->shash_id, psk, psk_len,
+					sq->ctrl->subsysnqn,
+					sq->ctrl->hostnqn, &digest);
+	if (ret) {
+		pr_warn("%s: ctrl %d qid %d failed to generate digest, error %d\n",
+			__func__, sq->ctrl->cntlid, sq->qid, ret);
+		goto out_free_psk;
+	}
+	ret = nvme_auth_derive_tls_psk(sq->ctrl->shash_id, psk, psk_len,
+				       digest, &tls_psk);
+	if (ret) {
+		pr_warn("%s: ctrl %d qid %d failed to derive TLS PSK, error %d\n",
+			__func__, sq->ctrl->cntlid, sq->qid, ret);
+		goto out_free_digest;
+	}
+#ifdef CONFIG_NVME_TARGET_TCP_TLS
+	tls_key = nvme_tls_psk_refresh(NULL, sq->ctrl->hostnqn, sq->ctrl->subsysnqn,
+				       sq->ctrl->shash_id, true, tls_psk, psk_len, digest);
+	if (IS_ERR(tls_key)) {
+		pr_warn("%s: ctrl %d qid %d failed to refresh key, error %ld\n",
+			__func__, sq->ctrl->cntlid, sq->qid, PTR_ERR(tls_key));
+		tls_key = NULL;
+		kfree_sensitive(tls_psk);
+	}
+	if (sq->ctrl->tls_key)
+		key_put(sq->ctrl->tls_key);
+	sq->ctrl->tls_key = tls_key;
+#endif
+
+out_free_digest:
+	kfree_sensitive(digest);
+out_free_psk:
+	kfree_sensitive(psk);
+}
diff --git a/drivers/nvme/target/fabrics-cmd-auth.c b/drivers/nvme/target/fabrics-cmd-auth.c
index d68c2dae5feb..4c392488c451 100644
--- a/drivers/nvme/target/fabrics-cmd-auth.c
+++ b/drivers/nvme/target/fabrics-cmd-auth.c
@@ -43,8 +43,26 @@ static u8 nvmet_auth_negotiate(struct nvmet_req *req, void *d)
 		 data->auth_protocol[0].dhchap.halen,
 		 data->auth_protocol[0].dhchap.dhlen);
 	req->sq->dhchap_tid = le16_to_cpu(data->t_id);
-	if (data->sc_c)
-		return NVME_AUTH_DHCHAP_FAILURE_CONCAT_MISMATCH;
+	if (data->sc_c != NVME_AUTH_SECP_NOSC) {
+		if (!IS_ENABLED(CONFIG_NVME_TARGET_TCP_TLS))
+			return NVME_AUTH_DHCHAP_FAILURE_CONCAT_MISMATCH;
+		/* Secure concatenation can only be enabled on the admin queue */
+		if (req->sq->qid)
+			return NVME_AUTH_DHCHAP_FAILURE_CONCAT_MISMATCH;
+		switch (data->sc_c) {
+		case NVME_AUTH_SECP_NEWTLSPSK:
+			if (nvmet_queue_tls_keyid(req->sq))
+				return NVME_AUTH_DHCHAP_FAILURE_CONCAT_MISMATCH;
+			break;
+		case NVME_AUTH_SECP_REPLACETLSPSK:
+			if (!nvmet_queue_tls_keyid(req->sq))
+				return NVME_AUTH_DHCHAP_FAILURE_CONCAT_MISMATCH;
+			break;
+		default:
+			return NVME_AUTH_DHCHAP_FAILURE_CONCAT_MISMATCH;
+		}
+		ctrl->concat = true;
+	}
 
 	if (data->napd != 1)
 		return NVME_AUTH_DHCHAP_FAILURE_HASH_UNUSABLE;
@@ -103,6 +121,13 @@ static u8 nvmet_auth_negotiate(struct nvmet_req *req, void *d)
 			 nvme_auth_dhgroup_name(fallback_dhgid));
 		ctrl->dh_gid = fallback_dhgid;
 	}
+	if (ctrl->dh_gid == NVME_AUTH_DHGROUP_NULL &&
+	    ctrl->concat) {
+		pr_debug("%s: ctrl %d qid %d: NULL DH group invalid "
+			 "for secure channel concatenation\n", __func__,
+			 ctrl->cntlid, req->sq->qid);
+		return NVME_AUTH_DHCHAP_FAILURE_CONCAT_MISMATCH;
+	}
 	pr_debug("%s: ctrl %d qid %d: selected DH group %s (%d)\n",
 		 __func__, ctrl->cntlid, req->sq->qid,
 		 nvme_auth_dhgroup_name(ctrl->dh_gid), ctrl->dh_gid);
@@ -154,6 +179,12 @@ static u8 nvmet_auth_reply(struct nvmet_req *req, void *d)
 	kfree(response);
 	pr_debug("%s: ctrl %d qid %d host authenticated\n",
 		 __func__, ctrl->cntlid, req->sq->qid);
+	if (!data->cvalid && ctrl->concat) {
+		pr_debug("%s: ctrl %d qid %d invalid challenge\n",
+			 __func__, ctrl->cntlid, req->sq->qid);
+		return NVME_AUTH_DHCHAP_FAILURE_FAILED;
+	}
+	req->sq->dhchap_s2 = le32_to_cpu(data->seqnum);
 	if (data->cvalid) {
 		req->sq->dhchap_c2 = kmemdup(data->rval + data->hl, data->hl,
 					     GFP_KERNEL);
@@ -163,11 +194,15 @@ static u8 nvmet_auth_reply(struct nvmet_req *req, void *d)
 		pr_debug("%s: ctrl %d qid %d challenge %*ph\n",
 			 __func__, ctrl->cntlid, req->sq->qid, data->hl,
 			 req->sq->dhchap_c2);
-	} else {
+	}
+	if (req->sq->dhchap_s2 == 0) {
+		if (ctrl->concat)
+			nvmet_auth_insert_psk(req->sq);
 		req->sq->authenticated = true;
+		kfree(req->sq->dhchap_c2);
 		req->sq->dhchap_c2 = NULL;
-	}
-	req->sq->dhchap_s2 = le32_to_cpu(data->seqnum);
+	} else if (!data->cvalid)
+		req->sq->authenticated = true;
 
 	return 0;
 }
@@ -241,7 +276,7 @@ void nvmet_execute_auth_send(struct nvmet_req *req)
 			pr_debug("%s: ctrl %d qid %d reset negotiation\n",
 				 __func__, ctrl->cntlid, req->sq->qid);
 			if (!req->sq->qid) {
-				dhchap_status = nvmet_setup_auth(ctrl);
+				dhchap_status = nvmet_setup_auth(ctrl, req);
 				if (dhchap_status) {
 					pr_err("ctrl %d qid 0 failed to setup re-authentication\n",
 					       ctrl->cntlid);
@@ -298,6 +333,8 @@ void nvmet_execute_auth_send(struct nvmet_req *req)
 		}
 		goto done_kfree;
 	case NVME_AUTH_DHCHAP_MESSAGE_SUCCESS2:
+		if (ctrl->concat)
+			nvmet_auth_insert_psk(req->sq);
 		req->sq->authenticated = true;
 		pr_debug("%s: ctrl %d qid %d ctrl authenticated\n",
 			 __func__, ctrl->cntlid, req->sq->qid);
diff --git a/drivers/nvme/target/fabrics-cmd.c b/drivers/nvme/target/fabrics-cmd.c
index 344ab75d8864..1aabf55ef0a8 100644
--- a/drivers/nvme/target/fabrics-cmd.c
+++ b/drivers/nvme/target/fabrics-cmd.c
@@ -199,10 +199,19 @@ static u16 nvmet_install_queue(struct nvmet_ctrl *ctrl, struct nvmet_req *req)
 	return ret;
 }
 
-static u32 nvmet_connect_result(struct nvmet_ctrl *ctrl)
+static u32 nvmet_connect_result(struct nvmet_ctrl *ctrl, struct nvmet_req *req)
 {
+	bool needs_auth = nvmet_has_auth(ctrl, req);
+
+	/* Do not authenticate I/O queues for secure concatenation */
+	if (ctrl->concat && req->sq->qid)
+		needs_auth = false;
+
+	pr_debug("%s: ctrl %d qid %d should %sauthenticate, tls psk %08x\n",
+		 __func__, ctrl->cntlid, req->sq->qid,
+		 needs_auth ? "" : "not ", nvmet_queue_tls_keyid(req->sq));
 	return (u32)ctrl->cntlid |
-		(nvmet_has_auth(ctrl) ? NVME_CONNECT_AUTHREQ_ATR : 0);
+		(needs_auth ? NVME_CONNECT_AUTHREQ_ATR : 0);
 }
 
 static void nvmet_execute_admin_connect(struct nvmet_req *req)
@@ -254,7 +263,7 @@ static void nvmet_execute_admin_connect(struct nvmet_req *req)
 
 	uuid_copy(&ctrl->hostid, &d->hostid);
 
-	dhchap_status = nvmet_setup_auth(ctrl);
+	dhchap_status = nvmet_setup_auth(ctrl, req);
 	if (dhchap_status) {
 		pr_err("Failed to setup authentication, dhchap status %u\n",
 		       dhchap_status);
@@ -272,12 +281,13 @@ static void nvmet_execute_admin_connect(struct nvmet_req *req)
 		goto out;
 	}
 
-	pr_info("creating %s controller %d for subsystem %s for NQN %s%s%s.\n",
+	pr_info("creating %s controller %d for subsystem %s for NQN %s%s%s%s.\n",
 		nvmet_is_disc_subsys(ctrl->subsys) ? "discovery" : "nvm",
 		ctrl->cntlid, ctrl->subsys->subsysnqn, ctrl->hostnqn,
-		ctrl->pi_support ? " T10-PI is enabled" : "",
-		nvmet_has_auth(ctrl) ? " with DH-HMAC-CHAP" : "");
-	req->cqe->result.u32 = cpu_to_le32(nvmet_connect_result(ctrl));
+		ctrl->pi_support ? ", T10-PI" : "",
+		nvmet_has_auth(ctrl, req) ? ", DH-HMAC-CHAP" : "",
+		nvmet_queue_tls_keyid(req->sq) ? ", TLS" : "");
+	req->cqe->result.u32 = cpu_to_le32(nvmet_connect_result(ctrl, req));
 out:
 	kfree(d);
 complete:
@@ -336,7 +346,7 @@ static void nvmet_execute_io_connect(struct nvmet_req *req)
 		goto out_ctrl_put;
 
 	pr_debug("adding queue %d to ctrl %d.\n", qid, ctrl->cntlid);
-	req->cqe->result.u32 = cpu_to_le32(nvmet_connect_result(ctrl));
+	req->cqe->result.u32 = cpu_to_le32(nvmet_connect_result(ctrl, req));
 out:
 	kfree(d);
 complete:
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index 190f55e6d753..c2e17201c757 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -121,6 +121,9 @@ struct nvmet_sq {
 	u32			dhchap_s2;
 	u8			*dhchap_skey;
 	int			dhchap_skey_len;
+#endif
+#ifdef CONFIG_NVME_TARGET_TCP_TLS
+	struct key		*tls_key;
 #endif
 	struct completion	free_done;
 	struct completion	confirm_done;
@@ -237,6 +240,7 @@ struct nvmet_ctrl {
 	u64			err_counter;
 	struct nvme_error_slot	slots[NVMET_ERROR_LOG_SLOTS];
 	bool			pi_support;
+	bool			concat;
 #ifdef CONFIG_NVME_TARGET_AUTH
 	struct nvme_dhchap_key	*host_key;
 	struct nvme_dhchap_key	*ctrl_key;
@@ -246,6 +250,9 @@ struct nvmet_ctrl {
 	u8			*dh_key;
 	size_t			dh_keysize;
 #endif
+#ifdef CONFIG_NVME_TARGET_TCP_TLS
+	struct key		*tls_key;
+#endif
 };
 
 struct nvmet_subsys {
@@ -716,13 +723,29 @@ static inline void nvmet_req_bio_put(struct nvmet_req *req, struct bio *bio)
 		bio_put(bio);
 }
 
+#ifdef CONFIG_NVME_TARGET_TCP_TLS
+static inline key_serial_t nvmet_queue_tls_keyid(struct nvmet_sq *sq)
+{
+	return sq->tls_key ? key_serial(sq->tls_key) : 0;
+}
+static inline void nvmet_sq_put_tls_key(struct nvmet_sq *sq)
+{
+	if (sq->tls_key) {
+		key_put(sq->tls_key);
+		sq->tls_key = NULL;
+	}
+}
+#else
+static inline key_serial_t nvmet_queue_tls_keyid(struct nvmet_sq *sq) { return 0; }
+static inline void nvmet_sq_put_tls_key(struct nvmet_sq *sq) {}
+#endif
 #ifdef CONFIG_NVME_TARGET_AUTH
 void nvmet_execute_auth_send(struct nvmet_req *req);
 void nvmet_execute_auth_receive(struct nvmet_req *req);
 int nvmet_auth_set_key(struct nvmet_host *host, const char *secret,
 		       bool set_ctrl);
 int nvmet_auth_set_host_hash(struct nvmet_host *host, const char *hash);
-u8 nvmet_setup_auth(struct nvmet_ctrl *ctrl);
+u8 nvmet_setup_auth(struct nvmet_ctrl *ctrl, struct nvmet_req *req);
 void nvmet_auth_sq_init(struct nvmet_sq *sq);
 void nvmet_destroy_auth(struct nvmet_ctrl *ctrl);
 void nvmet_auth_sq_free(struct nvmet_sq *sq);
@@ -732,16 +755,18 @@ int nvmet_auth_host_hash(struct nvmet_req *req, u8 *response,
 			 unsigned int hash_len);
 int nvmet_auth_ctrl_hash(struct nvmet_req *req, u8 *response,
 			 unsigned int hash_len);
-static inline bool nvmet_has_auth(struct nvmet_ctrl *ctrl)
+static inline bool nvmet_has_auth(struct nvmet_ctrl *ctrl, struct nvmet_req *req)
 {
-	return ctrl->host_key != NULL;
+	return ctrl->host_key != NULL && !nvmet_queue_tls_keyid(req->sq);
 }
 int nvmet_auth_ctrl_exponential(struct nvmet_req *req,
 				u8 *buf, int buf_size);
 int nvmet_auth_ctrl_sesskey(struct nvmet_req *req,
 			    u8 *buf, int buf_size);
+void nvmet_auth_insert_psk(struct nvmet_sq *sq);
 #else
-static inline u8 nvmet_setup_auth(struct nvmet_ctrl *ctrl)
+static inline u8 nvmet_setup_auth(struct nvmet_ctrl *ctrl,
+				  struct nvmet_req *req)
 {
 	return 0;
 }
@@ -754,11 +779,12 @@ static inline bool nvmet_check_auth_status(struct nvmet_req *req)
 {
 	return true;
 }
-static inline bool nvmet_has_auth(struct nvmet_ctrl *ctrl)
+static inline bool nvmet_has_auth(struct nvmet_ctrl *ctrl,
+				  struct nvmet_req *req)
 {
 	return false;
 }
 static inline const char *nvmet_dhchap_dhgroup_name(u8 dhgid) { return NULL; }
+static inline void nvmet_auth_insert_psk(struct nvmet_sq *sq) {};
 #endif
-
 #endif /* _NVMET_H */
diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c
index 5bff0d5464d1..49849f028966 100644
--- a/drivers/nvme/target/tcp.c
+++ b/drivers/nvme/target/tcp.c
@@ -1073,10 +1073,11 @@ static int nvmet_tcp_done_recv_pdu(struct nvmet_tcp_queue *queue)
 
 	if (unlikely(!nvmet_req_init(req, &queue->nvme_cq,
 			&queue->nvme_sq, &nvmet_tcp_ops))) {
-		pr_err("failed cmd %p id %d opcode %d, data_len: %d\n",
+		pr_err("failed cmd %p id %d opcode %d, data_len: %d, status: %04x\n",
 			req->cmd, req->cmd->common.command_id,
 			req->cmd->common.opcode,
-			le32_to_cpu(req->cmd->common.dptr.sgl.length));
+		       le32_to_cpu(req->cmd->common.dptr.sgl.length),
+		       le16_to_cpu(req->cqe->status));
 
 		nvmet_tcp_handle_req_failure(queue, queue->cmd, req);
 		return 0;
@@ -1602,6 +1603,7 @@ static void nvmet_tcp_release_queue_work(struct work_struct *w)
 	/* stop accepting incoming data */
 	queue->rcv_state = NVMET_TCP_RECV_ERR;
 
+	nvmet_sq_put_tls_key(&queue->nvme_sq);
 	nvmet_tcp_uninit_data_in_cmds(queue);
 	nvmet_sq_destroy(&queue->nvme_sq);
 	cancel_work_sync(&queue->io_work);
@@ -1807,6 +1809,23 @@ static void nvmet_tcp_tls_handshake_done(void *data, int status,
 	spin_unlock_bh(&queue->state_lock);
 
 	cancel_delayed_work_sync(&queue->tls_handshake_tmo_work);
+
+	if (!status) {
+		struct key *tls_key = nvme_tls_key_lookup(peerid);
+
+		if (IS_ERR(tls_key)) {
+			pr_warn("%s: queue %d failed to lookup key %x\n",
+				__func__, queue->idx, peerid);
+			spin_lock_bh(&queue->state_lock);
+			queue->state = NVMET_TCP_Q_FAILED;
+			spin_unlock_bh(&queue->state_lock);
+			status = PTR_ERR(tls_key);
+		} else {
+			pr_debug("%s: queue %d using TLS PSK %x\n",
+				 __func__, queue->idx, peerid);
+			queue->nvme_sq.tls_key = tls_key;
+		}
+	}
 	if (status)
 		nvmet_tcp_schedule_release_queue(queue);
 	else
-- 
2.35.3

Re: [PATCH 1/8] crypto,fs: Separate out hkdf_extract() and hkdf_expand()

[Eric Biggers]

On Thu, Jul 18, 2024 at 05:06:51PM +0200, Hannes Reinecke wrote:
> Separate out the HKDF functions into a separate file to make them
> available to other callers.
> 
> Cc: Eric Biggers <ebiggers@kernel.org>
> Cc: linux-crypto@vger.kernel.org
> Signed-off-by: Hannes Reinecke <hare@kernel.org>
> ---
>  crypto/Makefile       |   1 +
>  crypto/hkdf.c         | 112 ++++++++++++++++++++++++++++++++++++++++++
>  fs/crypto/hkdf.c      |  68 ++++---------------------
>  include/crypto/hkdf.h |  18 +++++++
>  4 files changed, 140 insertions(+), 59 deletions(-)
>  create mode 100644 crypto/hkdf.c
>  create mode 100644 include/crypto/hkdf.h

I was only sent patch 1, so this is unreviewable as there is no context.

- Eric

Re: [PATCH 1/8] crypto,fs: Separate out hkdf_extract() and hkdf_expand()

[Hannes Reinecke]

On 7/19/24 01:14, Eric Biggers wrote:
> On Thu, Jul 18, 2024 at 05:06:51PM +0200, Hannes Reinecke wrote:
>> Separate out the HKDF functions into a separate file to make them
>> available to other callers.
>>
>> Cc: Eric Biggers <ebiggers@kernel.org>
>> Cc: linux-crypto@vger.kernel.org
>> Signed-off-by: Hannes Reinecke <hare@kernel.org>
>> ---
>>   crypto/Makefile       |   1 +
>>   crypto/hkdf.c         | 112 ++++++++++++++++++++++++++++++++++++++++++
>>   fs/crypto/hkdf.c      |  68 ++++---------------------
>>   include/crypto/hkdf.h |  18 +++++++
>>   4 files changed, 140 insertions(+), 59 deletions(-)
>>   create mode 100644 crypto/hkdf.c
>>   create mode 100644 include/crypto/hkdf.h
> 
> I was only sent patch 1, so this is unreviewable as there is no context.
> 
Sorry. Will include you with the full patchset for the next round.
The remainder of the patch series is just calling into the just exported
functions to derive TLS PSK keys, wasn't sure if you'd be interested in
that.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich

Re: [PATCH 6/8] nvme-tcp: request secure channel concatenation

[Sagi Grimberg]

On 18/07/2024 18:06, Hannes Reinecke wrote:
> Add a fabrics option 'concat' to request secure channel concatenation.
> When secure channel concatenation is enabled a 'generated PSK' is inserted
> into the keyring such that it's available after reset.
>
> Signed-off-by: Hannes Reinecke <hare@kernel.org>
> ---
>   drivers/nvme/host/auth.c    | 100 ++++++++++++++++++++++++++++++++++--
>   drivers/nvme/host/fabrics.c |  34 ++++++++++--
>   drivers/nvme/host/fabrics.h |   3 ++
>   drivers/nvme/host/tcp.c     |  56 +++++++++++++++++---
>   include/linux/nvme.h        |   7 +++
>   5 files changed, 188 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/nvme/host/auth.c b/drivers/nvme/host/auth.c
> index 371e14f0a203..5f71aa7b5e27 100644
> --- a/drivers/nvme/host/auth.c
> +++ b/drivers/nvme/host/auth.c
> @@ -12,6 +12,7 @@
>   #include "nvme.h"
>   #include "fabrics.h"
>   #include <linux/nvme-auth.h>
> +#include <linux/nvme-keyring.h>
>   
>   #define CHAP_BUF_SIZE 4096
>   static struct kmem_cache *nvme_chap_buf_cache;
> @@ -131,7 +132,12 @@ static int nvme_auth_set_dhchap_negotiate_data(struct nvme_ctrl *ctrl,
>   	data->auth_type = NVME_AUTH_COMMON_MESSAGES;
>   	data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_NEGOTIATE;
>   	data->t_id = cpu_to_le16(chap->transaction);
> -	data->sc_c = 0; /* No secure channel concatenation */
> +	if (!ctrl->opts->concat || chap->qid != 0)
> +		data->sc_c = NVME_AUTH_SECP_NOSC;
> +	else if (ctrl->opts->tls_key)
> +		data->sc_c = NVME_AUTH_SECP_REPLACETLSPSK;
> +	else
> +		data->sc_c = NVME_AUTH_SECP_NEWTLSPSK;
>   	data->napd = 1;
>   	data->auth_protocol[0].dhchap.authid = NVME_AUTH_DHCHAP_AUTH_ID;
>   	data->auth_protocol[0].dhchap.halen = 3;
> @@ -311,8 +317,9 @@ static int nvme_auth_set_dhchap_reply_data(struct nvme_ctrl *ctrl,
>   	data->hl = chap->hash_len;
>   	data->dhvlen = cpu_to_le16(chap->host_key_len);
>   	memcpy(data->rval, chap->response, chap->hash_len);
> -	if (ctrl->ctrl_key) {
> +	if (ctrl->ctrl_key)
>   		chap->bi_directional = true;
> +	if (ctrl->ctrl_key || ctrl->opts->concat) {
>   		get_random_bytes(chap->c2, chap->hash_len);
>   		data->cvalid = 1;
>   		memcpy(data->rval + chap->hash_len, chap->c2,
> @@ -322,7 +329,10 @@ static int nvme_auth_set_dhchap_reply_data(struct nvme_ctrl *ctrl,
>   	} else {
>   		memset(chap->c2, 0, chap->hash_len);
>   	}
> -	chap->s2 = nvme_auth_get_seqnum();
> +	if (ctrl->opts->concat)
> +		chap->s2 = 0;
> +	else
> +		chap->s2 = nvme_auth_get_seqnum();
>   	data->seqnum = cpu_to_le32(chap->s2);
>   	if (chap->host_key_len) {
>   		dev_dbg(ctrl->device, "%s: qid %d host public key %*ph\n",
> @@ -677,6 +687,76 @@ static void nvme_auth_free_dhchap(struct nvme_dhchap_queue_context *chap)
>   		crypto_free_kpp(chap->dh_tfm);
>   }
>   
> +static int nvme_auth_secure_concat(struct nvme_ctrl *ctrl,
> +				   struct nvme_dhchap_queue_context *chap)
> +{
> +	u8 *psk, *digest, *tls_psk;
> +	struct key *tls_key;
> +	size_t psk_len;
> +	int ret = 0;
> +
> +	if (!chap->sess_key) {
> +		dev_warn(ctrl->device,
> +			 "%s: qid %d no session key negotiated\n",
> +			 __func__, chap->qid);
> +		return -ENOKEY;
> +	}
> +
> +	ret = nvme_auth_generate_psk(chap->hash_id, chap->sess_key,
> +				     chap->sess_key_len,
> +				     chap->c1, chap->c2,
> +				     chap->hash_len, &psk, &psk_len);
> +	if (ret) {
> +		dev_warn(ctrl->device,
> +			 "%s: qid %d failed to generate PSK, error %d\n",
> +			 __func__, chap->qid, ret);
> +		return ret;
> +	}
> +	dev_dbg(ctrl->device,
> +		  "%s: generated psk %*ph\n", __func__, (int)psk_len, psk);
> +
> +	ret = nvme_auth_generate_digest(chap->hash_id, psk, psk_len,
> +					ctrl->opts->subsysnqn,
> +					ctrl->opts->host->nqn, &digest);
> +	if (ret) {
> +		dev_warn(ctrl->device,
> +			 "%s: qid %d failed to generate digest, error %d\n",
> +			 __func__, chap->qid, ret);
> +		goto out_free_psk;
> +	};
> +	dev_dbg(ctrl->device, "%s: generated digest %s\n",
> +		 __func__, digest);
> +	ret = nvme_auth_derive_tls_psk(chap->hash_id, psk, psk_len, digest, &tls_psk);
> +	if (ret) {
> +		dev_warn(ctrl->device,
> +			 "%s: qid %d failed to derive TLS psk, error %d\n",
> +			 __func__, chap->qid, ret);
> +		goto out_free_digest;
> +	};
> +
> +	tls_key = nvme_tls_psk_refresh(ctrl->opts->keyring, ctrl->opts->host->nqn,
> +				       ctrl->opts->subsysnqn, chap->hash_id,
> +				       true, tls_psk, psk_len, digest);
> +	if (IS_ERR(tls_key)) {
> +		ret = PTR_ERR(tls_key);
> +		dev_warn(ctrl->device,
> +			 "%s: qid %d failed to insert generated key, error %d\n",
> +			 __func__, chap->qid, ret);
> +		tls_key = NULL;
> +		kfree_sensitive(tls_psk);
> +	}
> +	if (ctrl->opts->tls_key) {
> +		key_revoke(ctrl->opts->tls_key);
> +		key_put(ctrl->opts->tls_key);
> +	}

Any reason why error in nvme_tls_psk_refres() does not goto the normal 
error handling? Is it acceptable to fail here? Maybe I'm missing 
something...
> +	ctrl->opts->tls_key = tls_key;
> +out_free_digest:
> +	kfree_sensitive(digest);
> +out_free_psk:
> +	kfree_sensitive(psk);
> +	return ret;
> +}
> +
>   static void nvme_queue_auth_work(struct work_struct *work)
>   {
>   	struct nvme_dhchap_queue_context *chap =
> @@ -833,6 +913,14 @@ static void nvme_queue_auth_work(struct work_struct *work)
>   	}
>   	if (!ret) {
>   		chap->error = 0;
> +		/* Secure concatenation can only be enabled on the admin queue */
> +		if (!chap->qid && ctrl->opts->concat &&
> +		    (ret = nvme_auth_secure_concat(ctrl, chap))) {
> +			dev_warn(ctrl->device,
> +				 "%s: qid %d failed to enable secure concatenation\n",
> +				 __func__, chap->qid);
> +			chap->error = ret;
> +		}
>   		return;
>   	}
>   
> @@ -912,6 +1000,12 @@ static void nvme_ctrl_auth_work(struct work_struct *work)
>   			 "qid 0: authentication failed\n");
>   		return;
>   	}
> +	/*
> +	 * Only run authentication on the admin queue for
> +	 * secure concatenation
> +	 */
> +	if (ctrl->opts->concat)
> +		return;
>   
>   	for (q = 1; q < ctrl->queue_count; q++) {
>   		ret = nvme_auth_negotiate(ctrl, q);
> diff --git a/drivers/nvme/host/fabrics.c b/drivers/nvme/host/fabrics.c
> index 432efcbf9e2f..93e9041b9657 100644
> --- a/drivers/nvme/host/fabrics.c
> +++ b/drivers/nvme/host/fabrics.c
> @@ -472,8 +472,9 @@ int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl)
>   	result = le32_to_cpu(res.u32);
>   	ctrl->cntlid = result & 0xFFFF;
>   	if (result & (NVME_CONNECT_AUTHREQ_ATR | NVME_CONNECT_AUTHREQ_ASCR)) {
> -		/* Secure concatenation is not implemented */
> -		if (result & NVME_CONNECT_AUTHREQ_ASCR) {
> +		/* Check for secure concatenation */
> +		if ((result & NVME_CONNECT_AUTHREQ_ASCR) &&
> +		    !ctrl->opts->concat) {
>   			dev_warn(ctrl->device,
>   				 "qid 0: secure concatenation is not supported\n");
>   			ret = -EOPNOTSUPP;
> @@ -550,7 +551,7 @@ int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, u16 qid)
>   		/* Secure concatenation is not implemented */
>   		if (result & NVME_CONNECT_AUTHREQ_ASCR) {
>   			dev_warn(ctrl->device,
> -				 "qid 0: secure concatenation is not supported\n");
> +				 "qid %d: secure concatenation is not supported\n", qid);
>   			ret = -EOPNOTSUPP;
>   			goto out_free_data;
>   		}
> @@ -706,6 +707,7 @@ static const match_table_t opt_tokens = {
>   #endif
>   #ifdef CONFIG_NVME_TCP_TLS
>   	{ NVMF_OPT_TLS,			"tls"			},
> +	{ NVMF_OPT_CONCAT,		"concat"		},
>   #endif
>   	{ NVMF_OPT_ERR,			NULL			}
>   };
> @@ -735,6 +737,7 @@ static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
>   	opts->tls = false;
>   	opts->tls_key = NULL;
>   	opts->keyring = NULL;
> +	opts->concat = false;
>   
>   	options = o = kstrdup(buf, GFP_KERNEL);
>   	if (!options)
> @@ -1053,6 +1056,14 @@ static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
>   			}
>   			opts->tls = true;
>   			break;
> +		case NVMF_OPT_CONCAT:
> +			if (!IS_ENABLED(CONFIG_NVME_TCP_TLS)) {
> +				pr_err("TLS is not supported\n");
> +				ret = -EINVAL;
> +				goto out;
> +			}
> +			opts->concat = true;
> +			break;
>   		default:
>   			pr_warn("unknown parameter or missing value '%s' in ctrl creation request\n",
>   				p);
> @@ -1079,6 +1090,23 @@ static int nvmf_parse_options(struct nvmf_ctrl_options *opts,
>   			pr_warn("failfast tmo (%d) larger than controller loss tmo (%d)\n",
>   				opts->fast_io_fail_tmo, ctrl_loss_tmo);
>   	}
> +	if (opts->concat) {
> +		if (opts->tls) {
> +			pr_err("Secure concatenation over TLS is not supported\n");
> +			ret = -EINVAL;
> +			goto out;
> +		}
> +		if (opts->tls_key) {
> +			pr_err("Cannot specify a TLS key for secure concatenation\n");
> +			ret = -EINVAL;
> +			goto out;
> +		}

I think you mean it is unsupported?

> +		if (!opts->dhchap_secret) {
> +			pr_err("Need to enable DH-CHAP for secure concatenation\n");
> +			ret = -EINVAL;
> +			goto out;
> +		}
> +	}
>   
>   	opts->host = nvmf_host_add(hostnqn, &hostid);
>   	if (IS_ERR(opts->host)) {
> diff --git a/drivers/nvme/host/fabrics.h b/drivers/nvme/host/fabrics.h
> index 21d75dc4a3a0..9cf5b020adba 100644
> --- a/drivers/nvme/host/fabrics.h
> +++ b/drivers/nvme/host/fabrics.h
> @@ -66,6 +66,7 @@ enum {
>   	NVMF_OPT_TLS		= 1 << 25,
>   	NVMF_OPT_KEYRING	= 1 << 26,
>   	NVMF_OPT_TLS_KEY	= 1 << 27,
> +	NVMF_OPT_CONCAT		= 1 << 28,
>   };
>   
>   /**
> @@ -101,6 +102,7 @@ enum {
>    * @keyring:    Keyring to use for key lookups
>    * @tls_key:    TLS key for encrypted connections (TCP)
>    * @tls:        Start TLS encrypted connections (TCP)
> + * @concat:     Enabled Secure channel concatenation (TCP)
>    * @disable_sqflow: disable controller sq flow control
>    * @hdr_digest: generate/verify header digest (TCP)
>    * @data_digest: generate/verify data digest (TCP)
> @@ -130,6 +132,7 @@ struct nvmf_ctrl_options {
>   	struct key		*keyring;
>   	struct key		*tls_key;
>   	bool			tls;
> +	bool			concat;
>   	bool			disable_sqflow;
>   	bool			hdr_digest;
>   	bool			data_digest;
> diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
> index 5885aa452aa1..b748e4033df2 100644
> --- a/drivers/nvme/host/tcp.c
> +++ b/drivers/nvme/host/tcp.c
> @@ -227,7 +227,7 @@ static inline bool nvme_tcp_tls_configured(struct nvme_ctrl *ctrl)
>   	if (!IS_ENABLED(CONFIG_NVME_TCP_TLS))
>   		return 0;
>   
> -	return ctrl->opts->tls;
> +	return ctrl->opts->tls || ctrl->opts->concat;
>   }
>   
>   static inline struct blk_mq_tags *nvme_tcp_tagset(struct nvme_tcp_queue *queue)
> @@ -1942,7 +1942,7 @@ static int nvme_tcp_alloc_admin_queue(struct nvme_ctrl *ctrl)
>   	if (nvme_tcp_tls_configured(ctrl)) {
>   		if (ctrl->opts->tls_key)
>   			pskid = key_serial(ctrl->opts->tls_key);
> -		else {
> +		else if (ctrl->opts->tls) {
>   			pskid = nvme_tls_psk_default(ctrl->opts->keyring,
>   						      ctrl->opts->host->nqn,
>   						      ctrl->opts->subsysnqn);
> @@ -1972,9 +1972,25 @@ static int __nvme_tcp_alloc_io_queues(struct nvme_ctrl *ctrl)
>   {
>   	int i, ret;
>   
> -	if (nvme_tcp_tls_configured(ctrl) && !ctrl->tls_pskid) {
> -		dev_err(ctrl->device, "no PSK negotiated\n");
> -		return -ENOKEY;
> +	if (nvme_tcp_tls_configured(ctrl)) {
> +		if (ctrl->opts->concat) {
> +			/*
> +			 * The generated PSK is stored in the
> +			 * fabric options
> +			 */
> +			if (!ctrl->opts->tls_key) {
> +				dev_err(ctrl->device, "no PSK generated\n");
> +				return -ENOKEY;
> +			}
> +			if (ctrl->tls_pskid &&
> +			    ctrl->tls_pskid != key_serial(ctrl->opts->tls_key)) {
> +				dev_err(ctrl->device, "Stale PSK id %08x\n", ctrl->tls_pskid);
> +				ctrl->tls_pskid = 0;
> +			}

What is the user supposed to do with a stale psk? meaning why print an error
and continue as usual?

> +		} else if (!ctrl->tls_pskid) {
> +			dev_err(ctrl->device, "no PSK negotiated\n");
> +			return -ENOKEY;
> +		}
>   	}
>   
>   	for (i = 1; i < ctrl->queue_count; i++) {
> @@ -2205,6 +2221,30 @@ static void nvme_tcp_reconnect_or_remove(struct nvme_ctrl *ctrl,
>   	}
>   }
>   
> +/*
> + * The TLS key needs to be revoked when:
> + * - concatenation is enabled and
> + *   -> This is a generated key and only valid for this session
> + * - the generated key is present in ctrl->tls_key and
> + *   -> authentication has completed and the key has been generated
> + * - tls has been enabled
> + *   -> otherwise we are about to reset the admin queue after authentication
> + *      to enable TLS with the generated key
> + */
> +static bool nvme_tcp_key_revoke_needed(struct nvme_ctrl *ctrl)
> +{
> +	return ctrl->opts->concat && ctrl->opts->tls_key && ctrl->tls_pskid;
> +}
> +
> +static void nvme_tcp_revoke_tls_key(struct nvme_ctrl *ctrl)
> +{
> +	dev_dbg(ctrl->device, "Wipe generated TLS PSK %08x\n",
> +		key_serial(ctrl->opts->tls_key));
> +	key_revoke(ctrl->opts->tls_key);
> +	key_put(ctrl->opts->tls_key);
> +	ctrl->opts->tls_key = NULL;
> +}

I think this belongs in a common place no?

> +
>   static int nvme_tcp_setup_ctrl(struct nvme_ctrl *ctrl, bool new)
>   {
>   	struct nvmf_ctrl_options *opts = ctrl->opts;
> @@ -2308,6 +2348,8 @@ static void nvme_tcp_error_recovery_work(struct work_struct *work)
>   				struct nvme_tcp_ctrl, err_work);
>   	struct nvme_ctrl *ctrl = &tcp_ctrl->ctrl;
>   
> +	if (nvme_tcp_key_revoke_needed(ctrl))
> +		nvme_tcp_revoke_tls_key(ctrl);

Should this maybe move to nvme_tcp_teardown_admin_qeueue ?

>   	nvme_stop_keep_alive(ctrl);
>   	flush_work(&ctrl->async_event_work);
>   	nvme_tcp_teardown_io_queues(ctrl, false);
> @@ -2348,6 +2390,8 @@ static void nvme_reset_ctrl_work(struct work_struct *work)
>   		container_of(work, struct nvme_ctrl, reset_work);
>   	int ret;
>   
> +	if (nvme_tcp_key_revoke_needed(ctrl))
> +		nvme_tcp_revoke_tls_key(ctrl);

Would eliminate this call...

Re: [PATCH 6/8] nvme-tcp: request secure channel concatenation

[Hannes Reinecke]

On 7/21/24 13:27, Sagi Grimberg wrote:
> 
> 
> 
> On 18/07/2024 18:06, Hannes Reinecke wrote:
>> Add a fabrics option 'concat' to request secure channel concatenation.
>> When secure channel concatenation is enabled a 'generated PSK' is 
>> inserted
>> into the keyring such that it's available after reset.
>>
>> Signed-off-by: Hannes Reinecke <hare@kernel.org>
>> ---
>>   drivers/nvme/host/auth.c    | 100 ++++++++++++++++++++++++++++++++++--
>>   drivers/nvme/host/fabrics.c |  34 ++++++++++--
>>   drivers/nvme/host/fabrics.h |   3 ++
>>   drivers/nvme/host/tcp.c     |  56 +++++++++++++++++---
>>   include/linux/nvme.h        |   7 +++
>>   5 files changed, 188 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/nvme/host/auth.c b/drivers/nvme/host/auth.c
>> index 371e14f0a203..5f71aa7b5e27 100644
>> --- a/drivers/nvme/host/auth.c
>> +++ b/drivers/nvme/host/auth.c
>> @@ -12,6 +12,7 @@
>>   #include "nvme.h"
>>   #include "fabrics.h"
>>   #include <linux/nvme-auth.h>
>> +#include <linux/nvme-keyring.h>
>>   #define CHAP_BUF_SIZE 4096
>>   static struct kmem_cache *nvme_chap_buf_cache;
>> @@ -131,7 +132,12 @@ static int 
>> nvme_auth_set_dhchap_negotiate_data(struct nvme_ctrl *ctrl,
>>       data->auth_type = NVME_AUTH_COMMON_MESSAGES;
>>       data->auth_id = NVME_AUTH_DHCHAP_MESSAGE_NEGOTIATE;
>>       data->t_id = cpu_to_le16(chap->transaction);
>> -    data->sc_c = 0; /* No secure channel concatenation */
>> +    if (!ctrl->opts->concat || chap->qid != 0)
>> +        data->sc_c = NVME_AUTH_SECP_NOSC;
>> +    else if (ctrl->opts->tls_key)
>> +        data->sc_c = NVME_AUTH_SECP_REPLACETLSPSK;
>> +    else
>> +        data->sc_c = NVME_AUTH_SECP_NEWTLSPSK;
>>       data->napd = 1;
>>       data->auth_protocol[0].dhchap.authid = NVME_AUTH_DHCHAP_AUTH_ID;
>>       data->auth_protocol[0].dhchap.halen = 3;
>> @@ -311,8 +317,9 @@ static int nvme_auth_set_dhchap_reply_data(struct 
>> nvme_ctrl *ctrl,
>>       data->hl = chap->hash_len;
>>       data->dhvlen = cpu_to_le16(chap->host_key_len);
>>       memcpy(data->rval, chap->response, chap->hash_len);
>> -    if (ctrl->ctrl_key) {
>> +    if (ctrl->ctrl_key)
>>           chap->bi_directional = true;
>> +    if (ctrl->ctrl_key || ctrl->opts->concat) {
>>           get_random_bytes(chap->c2, chap->hash_len);
>>           data->cvalid = 1;
>>           memcpy(data->rval + chap->hash_len, chap->c2,
>> @@ -322,7 +329,10 @@ static int nvme_auth_set_dhchap_reply_data(struct 
>> nvme_ctrl *ctrl,
>>       } else {
>>           memset(chap->c2, 0, chap->hash_len);
>>       }
>> -    chap->s2 = nvme_auth_get_seqnum();
>> +    if (ctrl->opts->concat)
>> +        chap->s2 = 0;
>> +    else
>> +        chap->s2 = nvme_auth_get_seqnum();
>>       data->seqnum = cpu_to_le32(chap->s2);
>>       if (chap->host_key_len) {
>>           dev_dbg(ctrl->device, "%s: qid %d host public key %*ph\n",
>> @@ -677,6 +687,76 @@ static void nvme_auth_free_dhchap(struct 
>> nvme_dhchap_queue_context *chap)
>>           crypto_free_kpp(chap->dh_tfm);
>>   }
>> +static int nvme_auth_secure_concat(struct nvme_ctrl *ctrl,
>> +                   struct nvme_dhchap_queue_context *chap)
>> +{
>> +    u8 *psk, *digest, *tls_psk;
>> +    struct key *tls_key;
>> +    size_t psk_len;
>> +    int ret = 0;
>> +
>> +    if (!chap->sess_key) {
>> +        dev_warn(ctrl->device,
>> +             "%s: qid %d no session key negotiated\n",
>> +             __func__, chap->qid);
>> +        return -ENOKEY;
>> +    }
>> +
>> +    ret = nvme_auth_generate_psk(chap->hash_id, chap->sess_key,
>> +                     chap->sess_key_len,
>> +                     chap->c1, chap->c2,
>> +                     chap->hash_len, &psk, &psk_len);
>> +    if (ret) {
>> +        dev_warn(ctrl->device,
>> +             "%s: qid %d failed to generate PSK, error %d\n",
>> +             __func__, chap->qid, ret);
>> +        return ret;
>> +    }
>> +    dev_dbg(ctrl->device,
>> +          "%s: generated psk %*ph\n", __func__, (int)psk_len, psk);
>> +
>> +    ret = nvme_auth_generate_digest(chap->hash_id, psk, psk_len,
>> +                    ctrl->opts->subsysnqn,
>> +                    ctrl->opts->host->nqn, &digest);
>> +    if (ret) {
>> +        dev_warn(ctrl->device,
>> +             "%s: qid %d failed to generate digest, error %d\n",
>> +             __func__, chap->qid, ret);
>> +        goto out_free_psk;
>> +    };
>> +    dev_dbg(ctrl->device, "%s: generated digest %s\n",
>> +         __func__, digest);
>> +    ret = nvme_auth_derive_tls_psk(chap->hash_id, psk, psk_len, 
>> digest, &tls_psk);
>> +    if (ret) {
>> +        dev_warn(ctrl->device,
>> +             "%s: qid %d failed to derive TLS psk, error %d\n",
>> +             __func__, chap->qid, ret);
>> +        goto out_free_digest;
>> +    };
>> +
>> +    tls_key = nvme_tls_psk_refresh(ctrl->opts->keyring, 
>> ctrl->opts->host->nqn,
>> +                       ctrl->opts->subsysnqn, chap->hash_id,
>> +                       true, tls_psk, psk_len, digest);
>> +    if (IS_ERR(tls_key)) {
>> +        ret = PTR_ERR(tls_key);
>> +        dev_warn(ctrl->device,
>> +             "%s: qid %d failed to insert generated key, error %d\n",
>> +             __func__, chap->qid, ret);
>> +        tls_key = NULL;
>> +        kfree_sensitive(tls_psk);
>> +    }
>> +    if (ctrl->opts->tls_key) {
>> +        key_revoke(ctrl->opts->tls_key);
>> +        key_put(ctrl->opts->tls_key);
>> +    }
> 
> Any reason why error in nvme_tls_psk_refres() does not goto the normal 
> error handling? Is it acceptable to fail here? Maybe I'm missing 
> something...

Hmm? But we do; we are setting 'ret' to a non-zero value, and then
trigger the normal error handling ...
Or did you mean something else?

>> +    ctrl->opts->tls_key = tls_key;
>> +out_free_digest:
>> +    kfree_sensitive(digest);
>> +out_free_psk:
>> +    kfree_sensitive(psk);
>> +    return ret;
>> +}
>> +
>>   static void nvme_queue_auth_work(struct work_struct *work)
>>   {
>>       struct nvme_dhchap_queue_context *chap =
>> @@ -833,6 +913,14 @@ static void nvme_queue_auth_work(struct 
>> work_struct *work)
>>       }
>>       if (!ret) {
>>           chap->error = 0;
>> +        /* Secure concatenation can only be enabled on the admin 
>> queue */
>> +        if (!chap->qid && ctrl->opts->concat &&
>> +            (ret = nvme_auth_secure_concat(ctrl, chap))) {
>> +            dev_warn(ctrl->device,
>> +                 "%s: qid %d failed to enable secure concatenation\n",
>> +                 __func__, chap->qid);
>> +            chap->error = ret;
>> +        }
>>           return;
>>       }
>> @@ -912,6 +1000,12 @@ static void nvme_ctrl_auth_work(struct 
>> work_struct *work)
>>                "qid 0: authentication failed\n");
>>           return;
>>       }
>> +    /*
>> +     * Only run authentication on the admin queue for
>> +     * secure concatenation
>> +     */
>> +    if (ctrl->opts->concat)
>> +        return;
>>       for (q = 1; q < ctrl->queue_count; q++) {
>>           ret = nvme_auth_negotiate(ctrl, q);
>> diff --git a/drivers/nvme/host/fabrics.c b/drivers/nvme/host/fabrics.c
>> index 432efcbf9e2f..93e9041b9657 100644
>> --- a/drivers/nvme/host/fabrics.c
>> +++ b/drivers/nvme/host/fabrics.c
>> @@ -472,8 +472,9 @@ int nvmf_connect_admin_queue(struct nvme_ctrl *ctrl)
>>       result = le32_to_cpu(res.u32);
>>       ctrl->cntlid = result & 0xFFFF;
>>       if (result & (NVME_CONNECT_AUTHREQ_ATR | 
>> NVME_CONNECT_AUTHREQ_ASCR)) {
>> -        /* Secure concatenation is not implemented */
>> -        if (result & NVME_CONNECT_AUTHREQ_ASCR) {
>> +        /* Check for secure concatenation */
>> +        if ((result & NVME_CONNECT_AUTHREQ_ASCR) &&
>> +            !ctrl->opts->concat) {
>>               dev_warn(ctrl->device,
>>                    "qid 0: secure concatenation is not supported\n");
>>               ret = -EOPNOTSUPP;
>> @@ -550,7 +551,7 @@ int nvmf_connect_io_queue(struct nvme_ctrl *ctrl, 
>> u16 qid)
>>           /* Secure concatenation is not implemented */
>>           if (result & NVME_CONNECT_AUTHREQ_ASCR) {
>>               dev_warn(ctrl->device,
>> -                 "qid 0: secure concatenation is not supported\n");
>> +                 "qid %d: secure concatenation is not supported\n", 
>> qid);
>>               ret = -EOPNOTSUPP;
>>               goto out_free_data;
>>           }
>> @@ -706,6 +707,7 @@ static const match_table_t opt_tokens = {
>>   #endif
>>   #ifdef CONFIG_NVME_TCP_TLS
>>       { NVMF_OPT_TLS,            "tls"            },
>> +    { NVMF_OPT_CONCAT,        "concat"        },
>>   #endif
>>       { NVMF_OPT_ERR,            NULL            }
>>   };
>> @@ -735,6 +737,7 @@ static int nvmf_parse_options(struct 
>> nvmf_ctrl_options *opts,
>>       opts->tls = false;
>>       opts->tls_key = NULL;
>>       opts->keyring = NULL;
>> +    opts->concat = false;
>>       options = o = kstrdup(buf, GFP_KERNEL);
>>       if (!options)
>> @@ -1053,6 +1056,14 @@ static int nvmf_parse_options(struct 
>> nvmf_ctrl_options *opts,
>>               }
>>               opts->tls = true;
>>               break;
>> +        case NVMF_OPT_CONCAT:
>> +            if (!IS_ENABLED(CONFIG_NVME_TCP_TLS)) {
>> +                pr_err("TLS is not supported\n");
>> +                ret = -EINVAL;
>> +                goto out;
>> +            }
>> +            opts->concat = true;
>> +            break;
>>           default:
>>               pr_warn("unknown parameter or missing value '%s' in ctrl 
>> creation request\n",
>>                   p);
>> @@ -1079,6 +1090,23 @@ static int nvmf_parse_options(struct 
>> nvmf_ctrl_options *opts,
>>               pr_warn("failfast tmo (%d) larger than controller loss 
>> tmo (%d)\n",
>>                   opts->fast_io_fail_tmo, ctrl_loss_tmo);
>>       }
>> +    if (opts->concat) {
>> +        if (opts->tls) {
>> +            pr_err("Secure concatenation over TLS is not supported\n");
>> +            ret = -EINVAL;
>> +            goto out;
>> +        }
>> +        if (opts->tls_key) {
>> +            pr_err("Cannot specify a TLS key for secure 
>> concatenation\n");
>> +            ret = -EINVAL;
>> +            goto out;
>> +        }
> 
> I think you mean it is unsupported?
> 
Of course.

>> +        if (!opts->dhchap_secret) {
>> +            pr_err("Need to enable DH-CHAP for secure concatenation\n");
>> +            ret = -EINVAL;
>> +            goto out;
>> +        }
>> +    }
>>       opts->host = nvmf_host_add(hostnqn, &hostid);
>>       if (IS_ERR(opts->host)) {
>> diff --git a/drivers/nvme/host/fabrics.h b/drivers/nvme/host/fabrics.h
>> index 21d75dc4a3a0..9cf5b020adba 100644
>> --- a/drivers/nvme/host/fabrics.h
>> +++ b/drivers/nvme/host/fabrics.h
>> @@ -66,6 +66,7 @@ enum {
>>       NVMF_OPT_TLS        = 1 << 25,
>>       NVMF_OPT_KEYRING    = 1 << 26,
>>       NVMF_OPT_TLS_KEY    = 1 << 27,
>> +    NVMF_OPT_CONCAT        = 1 << 28,
>>   };
>>   /**
>> @@ -101,6 +102,7 @@ enum {
>>    * @keyring:    Keyring to use for key lookups
>>    * @tls_key:    TLS key for encrypted connections (TCP)
>>    * @tls:        Start TLS encrypted connections (TCP)
>> + * @concat:     Enabled Secure channel concatenation (TCP)
>>    * @disable_sqflow: disable controller sq flow control
>>    * @hdr_digest: generate/verify header digest (TCP)
>>    * @data_digest: generate/verify data digest (TCP)
>> @@ -130,6 +132,7 @@ struct nvmf_ctrl_options {
>>       struct key        *keyring;
>>       struct key        *tls_key;
>>       bool            tls;
>> +    bool            concat;
>>       bool            disable_sqflow;
>>       bool            hdr_digest;
>>       bool            data_digest;
>> diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
>> index 5885aa452aa1..b748e4033df2 100644
>> --- a/drivers/nvme/host/tcp.c
>> +++ b/drivers/nvme/host/tcp.c
>> @@ -227,7 +227,7 @@ static inline bool nvme_tcp_tls_configured(struct 
>> nvme_ctrl *ctrl)
>>       if (!IS_ENABLED(CONFIG_NVME_TCP_TLS))
>>           return 0;
>> -    return ctrl->opts->tls;
>> +    return ctrl->opts->tls || ctrl->opts->concat;
>>   }
>>   static inline struct blk_mq_tags *nvme_tcp_tagset(struct 
>> nvme_tcp_queue *queue)
>> @@ -1942,7 +1942,7 @@ static int nvme_tcp_alloc_admin_queue(struct 
>> nvme_ctrl *ctrl)
>>       if (nvme_tcp_tls_configured(ctrl)) {
>>           if (ctrl->opts->tls_key)
>>               pskid = key_serial(ctrl->opts->tls_key);
>> -        else {
>> +        else if (ctrl->opts->tls) {
>>               pskid = nvme_tls_psk_default(ctrl->opts->keyring,
>>                                 ctrl->opts->host->nqn,
>>                                 ctrl->opts->subsysnqn);
>> @@ -1972,9 +1972,25 @@ static int __nvme_tcp_alloc_io_queues(struct 
>> nvme_ctrl *ctrl)
>>   {
>>       int i, ret;
>> -    if (nvme_tcp_tls_configured(ctrl) && !ctrl->tls_pskid) {
>> -        dev_err(ctrl->device, "no PSK negotiated\n");
>> -        return -ENOKEY;
>> +    if (nvme_tcp_tls_configured(ctrl)) {
>> +        if (ctrl->opts->concat) {
>> +            /*
>> +             * The generated PSK is stored in the
>> +             * fabric options
>> +             */
>> +            if (!ctrl->opts->tls_key) {
>> +                dev_err(ctrl->device, "no PSK generated\n");
>> +                return -ENOKEY;
>> +            }
>> +            if (ctrl->tls_pskid &&
>> +                ctrl->tls_pskid != key_serial(ctrl->opts->tls_key)) {
>> +                dev_err(ctrl->device, "Stale PSK id %08x\n", 
>> ctrl->tls_pskid);
>> +                ctrl->tls_pskid = 0;
>> +            }
> 
> What is the user supposed to do with a stale psk? meaning why print an 
> error and continue as usual?
> 
Technically TLS handshake is independent from secure concatenation.
While we do generate a new TLS PSK from secure concatenation, there is
no guarantee that this TLS PSK is then selected from the TLS handshake.
So theoretically it's possible that the TLS handshake arrives at a 
different TLS PSK than the generated one.
But that is not actually an error, as both steps (authentication and
TLS handshake) have been successful. However, it's definitely an odd
situation, and we should tell the user about it.

>> +        } else if (!ctrl->tls_pskid) {
>> +            dev_err(ctrl->device, "no PSK negotiated\n");
>> +            return -ENOKEY;
>> +        }
>>       }
>>       for (i = 1; i < ctrl->queue_count; i++) {
>> @@ -2205,6 +2221,30 @@ static void nvme_tcp_reconnect_or_remove(struct 
>> nvme_ctrl *ctrl,
>>       }
>>   }
>> +/*
>> + * The TLS key needs to be revoked when:
>> + * - concatenation is enabled and
>> + *   -> This is a generated key and only valid for this session
>> + * - the generated key is present in ctrl->tls_key and
>> + *   -> authentication has completed and the key has been generated
>> + * - tls has been enabled
>> + *   -> otherwise we are about to reset the admin queue after 
>> authentication
>> + *      to enable TLS with the generated key
>> + */
>> +static bool nvme_tcp_key_revoke_needed(struct nvme_ctrl *ctrl)
>> +{
>> +    return ctrl->opts->concat && ctrl->opts->tls_key && ctrl->tls_pskid;
>> +}
>> +
>> +static void nvme_tcp_revoke_tls_key(struct nvme_ctrl *ctrl)
>> +{
>> +    dev_dbg(ctrl->device, "Wipe generated TLS PSK %08x\n",
>> +        key_serial(ctrl->opts->tls_key));
>> +    key_revoke(ctrl->opts->tls_key);
>> +    key_put(ctrl->opts->tls_key);
>> +    ctrl->opts->tls_key = NULL;
>> +}
> 
> I think this belongs in a common place no?
> 
?
Where?
'ctrl-opts' is pretty much initiator specific, so I am not sure where
it should go ...

>> +
>>   static int nvme_tcp_setup_ctrl(struct nvme_ctrl *ctrl, bool new)
>>   {
>>       struct nvmf_ctrl_options *opts = ctrl->opts;
>> @@ -2308,6 +2348,8 @@ static void nvme_tcp_error_recovery_work(struct 
>> work_struct *work)
>>                   struct nvme_tcp_ctrl, err_work);
>>       struct nvme_ctrl *ctrl = &tcp_ctrl->ctrl;
>> +    if (nvme_tcp_key_revoke_needed(ctrl))
>> +        nvme_tcp_revoke_tls_key(ctrl);
> 
> Should this maybe move to nvme_tcp_teardown_admin_qeueue ?
> 

Good point, will do.

>>       nvme_stop_keep_alive(ctrl);
>>       flush_work(&ctrl->async_event_work);
>>       nvme_tcp_teardown_io_queues(ctrl, false);
>> @@ -2348,6 +2390,8 @@ static void nvme_reset_ctrl_work(struct 
>> work_struct *work)
>>           container_of(work, struct nvme_ctrl, reset_work);
>>       int ret;
>> +    if (nvme_tcp_key_revoke_needed(ctrl))
>> +        nvme_tcp_revoke_tls_key(ctrl);
> 
> Would eliminate this call...

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich

Re: [PATCH 6/8] nvme-tcp: request secure channel concatenation

[Hannes Reinecke]

On 7/22/24 08:36, Hannes Reinecke wrote:
> On 7/21/24 13:27, Sagi Grimberg wrote:
>>
>>
>>
>> On 18/07/2024 18:06, Hannes Reinecke wrote:
>>> Add a fabrics option 'concat' to request secure channel concatenation.
>>> When secure channel concatenation is enabled a 'generated PSK' is 
>>> inserted
>>> into the keyring such that it's available after reset.
>>>
>>> Signed-off-by: Hannes Reinecke <hare@kernel.org>
>>> ---
>>>   drivers/nvme/host/auth.c    | 100 ++++++++++++++++++++++++++++++++++--
>>>   drivers/nvme/host/fabrics.c |  34 ++++++++++--
>>>   drivers/nvme/host/fabrics.h |   3 ++
>>>   drivers/nvme/host/tcp.c     |  56 +++++++++++++++++---
>>>   include/linux/nvme.h        |   7 +++
>>>   5 files changed, 188 insertions(+), 12 deletions(-)
>>>
[ .. ]
>>> +
>>>   static int nvme_tcp_setup_ctrl(struct nvme_ctrl *ctrl, bool new)
>>>   {
>>>       struct nvmf_ctrl_options *opts = ctrl->opts;
>>> @@ -2308,6 +2348,8 @@ static void nvme_tcp_error_recovery_work(struct 
>>> work_struct *work)
>>>                   struct nvme_tcp_ctrl, err_work);
>>>       struct nvme_ctrl *ctrl = &tcp_ctrl->ctrl;
>>> +    if (nvme_tcp_key_revoke_needed(ctrl))
>>> +        nvme_tcp_revoke_tls_key(ctrl);
>>
>> Should this maybe move to nvme_tcp_teardown_admin_qeueue ?
>>
> 
> Good point, will do.
> 
Actually, no.

That's precisely where we _cannot_ do it.
(Cf patch to reset the admin queue for secure concatenation).
We have three stages during secure concatenation:
1. authentication:
    ctrl->opts->concat = true, ctrl->opts->tls_key = NULL
    queue->tls_enabled = false
2. reset after authentication:
    ctrl->opts->concat = true, ctrl->opts->tls_key = <set>
    queue->tls_enabled = false
3. TLS enabled on the queue:
    ctrl->opts->concat = true, ctrl->opts->tls_key = <set>
    queue->tls_enabled = true

As we are calling 'nvme_teardown_admin_queue' in step 2)
we cannot clear the tls_key in that function.

Cheers,

Hannes
>>>       nvme_stop_keep_alive(ctrl);
>>>       flush_work(&ctrl->async_event_work);
>>>       nvme_tcp_teardown_io_queues(ctrl, false);
>>> @@ -2348,6 +2390,8 @@ static void nvme_reset_ctrl_work(struct 
>>> work_struct *work)
>>>           container_of(work, struct nvme_ctrl, reset_work);
>>>       int ret;
>>> +    if (nvme_tcp_key_revoke_needed(ctrl))
>>> +        nvme_tcp_revoke_tls_key(ctrl);
>>
>> Would eliminate this call...
> 
> Cheers,
> 
> Hannes

-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg
HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich