diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-02-21 17:18:12 +0100 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-02-21 17:18:12 +0100 |
commit | 33673dcb372b5d8179c22127ca71deb5f3dc7016 (patch) | |
tree | d182e9dc6aa127375a92b5eb619d6cd2ddc23ce7 /security/integrity/digsig_asymmetric.c | |
parent | KEYS: Revert one application of "Fix unreachable code" patch (diff) | |
parent | tpm/ibmvtpm: build only when IBM pseries is configured (diff) | |
download | linux-33673dcb372b5d8179c22127ca71deb5f3dc7016.tar.xz linux-33673dcb372b5d8179c22127ca71deb5f3dc7016.zip |
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
"This is basically a maintenance update for the TPM driver and EVM/IMA"
Fix up conflicts in lib/digsig.c and security/integrity/ima/ima_main.c
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (45 commits)
tpm/ibmvtpm: build only when IBM pseries is configured
ima: digital signature verification using asymmetric keys
ima: rename hash calculation functions
ima: use new crypto_shash API instead of old crypto_hash
ima: add policy support for file system uuid
evm: add file system uuid to EVM hmac
tpm_tis: check pnp_acpi_device return code
char/tpm/tpm_i2c_stm_st33: drop temporary variable for return value
char/tpm/tpm_i2c_stm_st33: remove dead assignment in tpm_st33_i2c_probe
char/tpm/tpm_i2c_stm_st33: Remove __devexit attribute
char/tpm/tpm_i2c_stm_st33: Don't use memcpy for one byte assignment
tpm_i2c_stm_st33: removed unused variables/code
TPM: Wait for TPM_ACCESS tpmRegValidSts to go high at startup
tpm: Fix cancellation of TPM commands (interrupt mode)
tpm: Fix cancellation of TPM commands (polling mode)
tpm: Store TPM vendor ID
TPM: Work around buggy TPMs that block during continue self test
tpm_i2c_stm_st33: fix oops when i2c client is unavailable
char/tpm: Use struct dev_pm_ops for power management
TPM: STMicroelectronics ST33 I2C BUILD STUFF
...
Diffstat (limited to 'security/integrity/digsig_asymmetric.c')
-rw-r--r-- | security/integrity/digsig_asymmetric.c | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/security/integrity/digsig_asymmetric.c b/security/integrity/digsig_asymmetric.c new file mode 100644 index 000000000000..b4754667659d --- /dev/null +++ b/security/integrity/digsig_asymmetric.c @@ -0,0 +1,115 @@ +/* + * Copyright (C) 2013 Intel Corporation + * + * Author: + * Dmitry Kasatkin <dmitry.kasatkin@intel.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, version 2 of the License. + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/err.h> +#include <linux/key-type.h> +#include <crypto/public_key.h> +#include <keys/asymmetric-type.h> + +#include "integrity.h" + +/* + * signature format v2 - for using with asymmetric keys + */ +struct signature_v2_hdr { + uint8_t version; /* signature format version */ + uint8_t hash_algo; /* Digest algorithm [enum pkey_hash_algo] */ + uint32_t keyid; /* IMA key identifier - not X509/PGP specific*/ + uint16_t sig_size; /* signature size */ + uint8_t sig[0]; /* signature payload */ +} __packed; + +/* + * Request an asymmetric key. + */ +static struct key *request_asymmetric_key(struct key *keyring, uint32_t keyid) +{ + struct key *key; + char name[12]; + + sprintf(name, "id:%x", keyid); + + pr_debug("key search: \"%s\"\n", name); + + if (keyring) { + /* search in specific keyring */ + key_ref_t kref; + kref = keyring_search(make_key_ref(keyring, 1), + &key_type_asymmetric, name); + if (IS_ERR(kref)) + key = ERR_CAST(kref); + else + key = key_ref_to_ptr(kref); + } else { + key = request_key(&key_type_asymmetric, name, NULL); + } + + if (IS_ERR(key)) { + pr_warn("Request for unknown key '%s' err %ld\n", + name, PTR_ERR(key)); + switch (PTR_ERR(key)) { + /* Hide some search errors */ + case -EACCES: + case -ENOTDIR: + case -EAGAIN: + return ERR_PTR(-ENOKEY); + default: + return key; + } + } + + pr_debug("%s() = 0 [%x]\n", __func__, key_serial(key)); + + return key; +} + +int asymmetric_verify(struct key *keyring, const char *sig, + int siglen, const char *data, int datalen) +{ + struct public_key_signature pks; + struct signature_v2_hdr *hdr = (struct signature_v2_hdr *)sig; + struct key *key; + int ret = -ENOMEM; + + if (siglen <= sizeof(*hdr)) + return -EBADMSG; + + siglen -= sizeof(*hdr); + + if (siglen != __be16_to_cpu(hdr->sig_size)) + return -EBADMSG; + + if (hdr->hash_algo >= PKEY_HASH__LAST) + return -ENOPKG; + + key = request_asymmetric_key(keyring, __be32_to_cpu(hdr->keyid)); + if (IS_ERR(key)) + return PTR_ERR(key); + + memset(&pks, 0, sizeof(pks)); + + pks.pkey_hash_algo = hdr->hash_algo; + pks.digest = (u8 *)data; + pks.digest_size = datalen; + pks.nr_mpi = 1; + pks.rsa.s = mpi_read_raw_data(hdr->sig, siglen); + + if (pks.rsa.s) + ret = verify_signature(key, &pks); + + mpi_free(pks.rsa.s); + key_put(key); + pr_debug("%s() = %d\n", __func__, ret); + return ret; +} |