Commit 79559c75 authored by Hannes Reinecke's avatar Hannes Reinecke Committed by Keith Busch
Browse files

nvme-keyring: restrict match length for version '1' identifiers 



TP8018 introduced a new TLS PSK identifier version (version 1), which appended
a PSK hash value to the existing identifier (cf NVMe TCP specification v1.1,
section 3.6.1.3 'TLS PSK and PSK Identity Derivation').
An original (version 0) identifier has the form:

NVMe0<type><hmac> <hostnqn> <subsysnqn>

and a version 1 identifier has the form:

NVMe1<type><hmac> <hostnqn> <subsysnqn> <hash>

This patch modifies the lookup algorthm to compare only the first part
of the identifier (excluding the hash value) to handle both version 0 and
version 1 identifiers.
And the spec declares 'version 0' identifiers obsolete, so the lookup
algorithm is modified to prever v1 identifiers.

Signed-off-by: default avatarHannes Reinecke <hare@kernel.org>
Reviewed-by: default avatarSagi Grimberg <sagi@grimberg.me>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarKeith Busch <kbusch@kernel.org>
parent 4e893ca8

drivers/nvme/common/keyring.c

+26 −10
Original line number Diff line number Diff line
@@ -36,14 +36,12 @@ static bool nvme_tls_psk_match(const struct key *key, 
		pr_debug("%s: no key description\n", __func__);

		return false;

	}

	match_len = strlen(key->description);

	pr_debug("%s: id %s len %zd\n", __func__, key->description, match_len);



	if (!match_data->raw_data) {

		pr_debug("%s: no match data\n", __func__);

		return false;

	}

	match_id = match_data->raw_data;

	match_len = strlen(match_id);

	pr_debug("%s: match '%s' '%s' len %zd\n",

		 __func__, match_id, key->description, match_len);

	return !memcmp(key->description, match_id, match_len);
@@ -71,7 +69,7 @@ static struct key_type nvme_tls_psk_key_type = { 


static struct key *nvme_tls_psk_lookup(struct key *keyring,

		const char *hostnqn, const char *subnqn,

		int hmac, bool generated)

		u8 hmac, u8 psk_ver, bool generated)

{

	char *identity;

	size_t identity_len = (NVMF_NQN_SIZE) * 2 + 11;
@@ -82,8 +80,8 @@ static struct key *nvme_tls_psk_lookup(struct key *keyring, 
	if (!identity)

		return ERR_PTR(-ENOMEM);



	snprintf(identity, identity_len, "NVMe0%c%02d %s %s",

		 generated ? 'G' : 'R', hmac, hostnqn, subnqn);

	snprintf(identity, identity_len, "NVMe%u%c%02u %s %s",

		 psk_ver, generated ? 'G' : 'R', hmac, hostnqn, subnqn);



	if (!keyring)

		keyring = nvme_keyring;
@@ -107,21 +105,38 @@ static struct key *nvme_tls_psk_lookup(struct key *keyring, 
/*

 * NVMe PSK priority list

 *

 * 'Retained' PSKs (ie 'generated == false')

 * should be preferred to 'generated' PSKs,

 * and SHA-384 should be preferred to SHA-256.

 * 'Retained' PSKs (ie 'generated == false') should be preferred to 'generated'

 * PSKs, PSKs with hash (psk_ver 1) should be preferred to PSKs without hash

 * (psk_ver 0), and SHA-384 should be preferred to SHA-256.

 */

static struct nvme_tls_psk_priority_list {

	bool generated;

	u8 psk_ver;

	enum nvme_tcp_tls_cipher cipher;

} nvme_tls_psk_prio[] = {

	{ .generated = false,

	  .psk_ver = 1,

	  .cipher = NVME_TCP_TLS_CIPHER_SHA384, },

	{ .generated = false,

	  .psk_ver = 1,

	  .cipher = NVME_TCP_TLS_CIPHER_SHA256, },

	{ .generated = false,

	  .psk_ver = 0,

	  .cipher = NVME_TCP_TLS_CIPHER_SHA384, },

	{ .generated = false,

	  .psk_ver = 0,

	  .cipher = NVME_TCP_TLS_CIPHER_SHA256, },

	{ .generated = true,

	  .psk_ver = 1,

	  .cipher = NVME_TCP_TLS_CIPHER_SHA384, },

	{ .generated = true,

	  .psk_ver = 1,

	  .cipher = NVME_TCP_TLS_CIPHER_SHA256, },

	{ .generated = true,

	  .psk_ver = 0,

	  .cipher = NVME_TCP_TLS_CIPHER_SHA384, },

	{ .generated = true,

	  .psk_ver = 0,

	  .cipher = NVME_TCP_TLS_CIPHER_SHA256, },

};
@@ -137,10 +152,11 @@ key_serial_t nvme_tls_psk_default(struct key *keyring, 


	for (prio = 0; prio < ARRAY_SIZE(nvme_tls_psk_prio); prio++) {

		bool generated = nvme_tls_psk_prio[prio].generated;

		u8 ver = nvme_tls_psk_prio[prio].psk_ver;

		enum nvme_tcp_tls_cipher cipher = nvme_tls_psk_prio[prio].cipher;



		tls_key = nvme_tls_psk_lookup(keyring, hostnqn, subnqn,

					      cipher, generated);

					      cipher, ver, generated);

		if (!IS_ERR(tls_key)) {

			tls_key_id = tls_key->serial;

			key_put(tls_key);