From 240730437deb213a58915830884e1a99045624dc Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Wed, 6 Feb 2019 17:24:51 +0100 Subject: KEYS: trusted: explicitly use tpm_chip structure from tpm_default_chip() When crypto agility support will be added to the TPM driver, users of the driver have to retrieve the allocated banks from chip->allocated_banks and use this information to prepare the array of tpm_digest structures to be passed to tpm_pcr_extend(). This patch retrieves a tpm_chip pointer from tpm_default_chip() so that the pointer can be used to prepare the array of tpm_digest structures. Signed-off-by: Roberto Sassu Reviewed-by: Jarkko Sakkinen Tested-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen --- security/keys/trusted.c | 38 ++++++++++++++++++++++++-------------- 1 file changed, 24 insertions(+), 14 deletions(-) (limited to 'security/keys') diff --git a/security/keys/trusted.c b/security/keys/trusted.c index 4d98f4f87236..5b852263eae1 100644 --- a/security/keys/trusted.c +++ b/security/keys/trusted.c @@ -34,6 +34,7 @@ static const char hmac_alg[] = "hmac(sha1)"; static const char hash_alg[] = "sha1"; +static struct tpm_chip *chip; struct sdesc { struct shash_desc shash; @@ -362,7 +363,7 @@ int trusted_tpm_send(unsigned char *cmd, size_t buflen) int rc; dump_tpm_buf(cmd); - rc = tpm_send(NULL, cmd, buflen); + rc = tpm_send(chip, cmd, buflen); dump_tpm_buf(cmd); if (rc > 0) /* Can't return positive return codes values to keyctl */ @@ -384,10 +385,10 @@ static int pcrlock(const int pcrnum) if (!capable(CAP_SYS_ADMIN)) return -EPERM; - ret = tpm_get_random(NULL, hash, SHA1_DIGEST_SIZE); + ret = tpm_get_random(chip, hash, SHA1_DIGEST_SIZE); if (ret != SHA1_DIGEST_SIZE) return ret; - return tpm_pcr_extend(NULL, pcrnum, hash) ? -EINVAL : 0; + return tpm_pcr_extend(chip, pcrnum, hash) ? -EINVAL : 0; } /* @@ -400,7 +401,7 @@ static int osap(struct tpm_buf *tb, struct osapsess *s, unsigned char ononce[TPM_NONCE_SIZE]; int ret; - ret = tpm_get_random(NULL, ononce, TPM_NONCE_SIZE); + ret = tpm_get_random(chip, ononce, TPM_NONCE_SIZE); if (ret != TPM_NONCE_SIZE) return ret; @@ -496,7 +497,7 @@ static int tpm_seal(struct tpm_buf *tb, uint16_t keytype, if (ret < 0) goto out; - ret = tpm_get_random(NULL, td->nonceodd, TPM_NONCE_SIZE); + ret = tpm_get_random(chip, td->nonceodd, TPM_NONCE_SIZE); if (ret != TPM_NONCE_SIZE) goto out; ordinal = htonl(TPM_ORD_SEAL); @@ -606,7 +607,7 @@ static int tpm_unseal(struct tpm_buf *tb, ordinal = htonl(TPM_ORD_UNSEAL); keyhndl = htonl(SRKHANDLE); - ret = tpm_get_random(NULL, nonceodd, TPM_NONCE_SIZE); + ret = tpm_get_random(chip, nonceodd, TPM_NONCE_SIZE); if (ret != TPM_NONCE_SIZE) { pr_info("trusted_key: tpm_get_random failed (%d)\n", ret); return ret; @@ -751,7 +752,7 @@ static int getoptions(char *c, struct trusted_key_payload *pay, int i; int tpm2; - tpm2 = tpm_is_tpm2(NULL); + tpm2 = tpm_is_tpm2(chip); if (tpm2 < 0) return tpm2; @@ -920,7 +921,7 @@ static struct trusted_key_options *trusted_options_alloc(void) struct trusted_key_options *options; int tpm2; - tpm2 = tpm_is_tpm2(NULL); + tpm2 = tpm_is_tpm2(chip); if (tpm2 < 0) return NULL; @@ -970,7 +971,7 @@ static int trusted_instantiate(struct key *key, size_t key_len; int tpm2; - tpm2 = tpm_is_tpm2(NULL); + tpm2 = tpm_is_tpm2(chip); if (tpm2 < 0) return tpm2; @@ -1011,7 +1012,7 @@ static int trusted_instantiate(struct key *key, switch (key_cmd) { case Opt_load: if (tpm2) - ret = tpm_unseal_trusted(NULL, payload, options); + ret = tpm_unseal_trusted(chip, payload, options); else ret = key_unseal(payload, options); dump_payload(payload); @@ -1021,13 +1022,13 @@ static int trusted_instantiate(struct key *key, break; case Opt_new: key_len = payload->key_len; - ret = tpm_get_random(NULL, payload->key, key_len); + ret = tpm_get_random(chip, payload->key, key_len); if (ret != key_len) { pr_info("trusted_key: key_create failed (%d)\n", ret); goto out; } if (tpm2) - ret = tpm_seal_trusted(NULL, payload, options); + ret = tpm_seal_trusted(chip, payload, options); else ret = key_seal(payload, options); if (ret < 0) @@ -1225,17 +1226,26 @@ static int __init init_trusted(void) { int ret; + chip = tpm_default_chip(); + if (!chip) + return -ENOENT; ret = trusted_shash_alloc(); if (ret < 0) - return ret; + goto err_put; ret = register_key_type(&key_type_trusted); if (ret < 0) - trusted_shash_release(); + goto err_release; + return 0; +err_release: + trusted_shash_release(); +err_put: + put_device(&chip->dev); return ret; } static void __exit cleanup_trusted(void) { + put_device(&chip->dev); trusted_shash_release(); unregister_key_type(&key_type_trusted); } -- cgit v1.2.1 From 0b6cf6b97b7ef1fa3c7fefab0cac897a1c4a3400 Mon Sep 17 00:00:00 2001 From: Roberto Sassu Date: Wed, 6 Feb 2019 17:24:52 +0100 Subject: tpm: pass an array of tpm_extend_digest structures to tpm_pcr_extend() Currently, tpm_pcr_extend() accepts as an input only a SHA1 digest. This patch replaces the hash parameter of tpm_pcr_extend() with an array of tpm_digest structures, so that the caller can provide a digest for each PCR bank currently allocated in the TPM. tpm_pcr_extend() will not extend banks for which no digest was provided, as it happened before this patch, but instead it requires that callers provide the full set of digests. Since the number of digests will always be chip->nr_allocated_banks, the count parameter has been removed. Due to the API change, ima_pcr_extend() and pcrlock() have been modified. Since the number of allocated banks is not known in advance, the memory for the digests must be dynamically allocated. To avoid performance degradation and to avoid that a PCR extend is not done due to lack of memory, the array of tpm_digest structures is allocated by the users of the TPM driver at initialization time. Signed-off-by: Roberto Sassu Reviewed-by: Jarkko Sakkinen Tested-by: Jarkko Sakkinen Tested-by: Mimi Zohar (on x86 for TPM 1.2 & PTT TPM 2.0) Signed-off-by: Jarkko Sakkinen --- security/keys/trusted.c | 41 +++++++++++++++++++++++++++++++++-------- 1 file changed, 33 insertions(+), 8 deletions(-) (limited to 'security/keys') diff --git a/security/keys/trusted.c b/security/keys/trusted.c index 5b852263eae1..bcc9c6ead7fd 100644 --- a/security/keys/trusted.c +++ b/security/keys/trusted.c @@ -35,6 +35,7 @@ static const char hmac_alg[] = "hmac(sha1)"; static const char hash_alg[] = "sha1"; static struct tpm_chip *chip; +static struct tpm_digest *digests; struct sdesc { struct shash_desc shash; @@ -380,15 +381,10 @@ EXPORT_SYMBOL_GPL(trusted_tpm_send); */ static int pcrlock(const int pcrnum) { - unsigned char hash[SHA1_DIGEST_SIZE]; - int ret; - if (!capable(CAP_SYS_ADMIN)) return -EPERM; - ret = tpm_get_random(chip, hash, SHA1_DIGEST_SIZE); - if (ret != SHA1_DIGEST_SIZE) - return ret; - return tpm_pcr_extend(chip, pcrnum, hash) ? -EINVAL : 0; + + return tpm_pcr_extend(chip, pcrnum, digests) ? -EINVAL : 0; } /* @@ -1222,6 +1218,29 @@ hashalg_fail: return ret; } +static int __init init_digests(void) +{ + u8 digest[TPM_MAX_DIGEST_SIZE]; + int ret; + int i; + + ret = tpm_get_random(chip, digest, TPM_MAX_DIGEST_SIZE); + if (ret < 0) + return ret; + if (ret < TPM_MAX_DIGEST_SIZE) + return -EFAULT; + + digests = kcalloc(chip->nr_allocated_banks, sizeof(*digests), + GFP_KERNEL); + if (!digests) + return -ENOMEM; + + for (i = 0; i < chip->nr_allocated_banks; i++) + memcpy(digests[i].digest, digest, TPM_MAX_DIGEST_SIZE); + + return 0; +} + static int __init init_trusted(void) { int ret; @@ -1229,15 +1248,20 @@ static int __init init_trusted(void) chip = tpm_default_chip(); if (!chip) return -ENOENT; - ret = trusted_shash_alloc(); + ret = init_digests(); if (ret < 0) goto err_put; + ret = trusted_shash_alloc(); + if (ret < 0) + goto err_free; ret = register_key_type(&key_type_trusted); if (ret < 0) goto err_release; return 0; err_release: trusted_shash_release(); +err_free: + kfree(digests); err_put: put_device(&chip->dev); return ret; @@ -1246,6 +1270,7 @@ err_put: static void __exit cleanup_trusted(void) { put_device(&chip->dev); + kfree(digests); trusted_shash_release(); unregister_key_type(&key_type_trusted); } -- cgit v1.2.1