keys, trusted: select hash algorithm for TPM2 chips
Added 'hash=' option for selecting the hash algorithm for add_key()
syscall and documentation for it.
Added entry for sm3-256 to the following tables in order to support
TPM_ALG_SM3_256:
* hash_algo_name
* hash_digest_size
Includes support for the following hash algorithms:
* sha1
* sha256
* sha384
* sha512
* sm3-256
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Peter Huewe <peterhuewe@gmx.de>
diff --git a/security/keys/Kconfig b/security/keys/Kconfig
index 72483b8..fe4d74e 100644
--- a/security/keys/Kconfig
+++ b/security/keys/Kconfig
@@ -54,6 +54,7 @@
select CRYPTO
select CRYPTO_HMAC
select CRYPTO_SHA1
+ select CRYPTO_HASH_INFO
help
This option provides support for creating, sealing, and unsealing
keys in the kernel. Trusted keys are random number symmetric keys,
diff --git a/security/keys/trusted.c b/security/keys/trusted.c
index 7c183c7..8f1300c 100644
--- a/security/keys/trusted.c
+++ b/security/keys/trusted.c
@@ -11,6 +11,7 @@
* See Documentation/security/keys-trusted-encrypted.txt
*/
+#include <crypto/hash_info.h>
#include <linux/uaccess.h>
#include <linux/module.h>
#include <linux/init.h>
@@ -710,7 +711,8 @@
Opt_err = -1,
Opt_new, Opt_load, Opt_update,
Opt_keyhandle, Opt_keyauth, Opt_blobauth,
- Opt_pcrinfo, Opt_pcrlock, Opt_migratable
+ Opt_pcrinfo, Opt_pcrlock, Opt_migratable,
+ Opt_hash,
};
static const match_table_t key_tokens = {
@@ -723,6 +725,7 @@
{Opt_pcrinfo, "pcrinfo=%s"},
{Opt_pcrlock, "pcrlock=%s"},
{Opt_migratable, "migratable=%s"},
+ {Opt_hash, "hash=%s"},
{Opt_err, NULL}
};
@@ -737,6 +740,14 @@
unsigned long handle;
unsigned long lock;
unsigned long token_mask = 0;
+ int i;
+ int tpm2;
+
+ tpm2 = tpm_is_tpm2(TPM_ANY_NUM);
+ if (tpm2 < 0)
+ return tpm2;
+
+ opt->hash = tpm2 ? HASH_ALGO_SHA256 : HASH_ALGO_SHA1;
while ((p = strsep(&c, " \t"))) {
if (*p == '\0' || *p == ' ' || *p == '\t')
@@ -790,6 +801,20 @@
return -EINVAL;
opt->pcrlock = lock;
break;
+ case Opt_hash:
+ for (i = 0; i < HASH_ALGO__LAST; i++) {
+ if (!strcmp(args[0].from, hash_algo_name[i])) {
+ opt->hash = i;
+ break;
+ }
+ }
+ if (i == HASH_ALGO__LAST)
+ return -EINVAL;
+ if (!tpm2 && i != HASH_ALGO_SHA1) {
+ pr_info("trusted_key: TPM 1.x only supports SHA-1.\n");
+ return -EINVAL;
+ }
+ break;
default:
return -EINVAL;
}