Instead of relying on the "imaevm_params.algo" global variable, which
is not concurrency-safe, define and use a local variable.
Update static verify_hash_v2(), verify_hash_v3(), and verify_hash_common()
function definitions to include a hash algorithm argument.
Similarly update ima_verify_signature2() and ima_calc_hash2() to define
and use a local hash algorithm variable.
Signed-off-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>
---
src/libimaevm.c | 40 ++++++++++++++++++++++++----------------
1 file changed, 24 insertions(+), 16 deletions(-)
diff --git a/src/libimaevm.c b/src/libimaevm.c
index 4c9da7a2f06b..18b6a6f27237 100644
--- a/src/libimaevm.c
+++ b/src/libimaevm.c
@@ -488,6 +488,7 @@ void init_public_keys(const char *keyfiles)
* (Note: signature_v2_hdr struct does not contain the 'type'.)
*/
static int verify_hash_common(void *public_keys, const char *file,
+ const char *hash_algo,
const unsigned char *hash,
int size, unsigned char *sig, int siglen)
{
@@ -499,7 +500,7 @@ static int verify_hash_common(void *public_keys, const char *file,
const char *st;
if (imaevm_params.verbose > LOG_INFO) {
- log_info("hash(%s): ", imaevm_params.hash_algo);
+ log_info("hash(%s): ", hash_algo);
log_dump(hash, size);
}
@@ -530,7 +531,7 @@ static int verify_hash_common(void *public_keys, const char *file,
if (!EVP_PKEY_verify_init(ctx))
goto err;
st = "EVP_get_digestbyname";
- if (!(md = EVP_get_digestbyname(imaevm_params.hash_algo)))
+ if (!(md = EVP_get_digestbyname(hash_algo)))
goto err;
st = "EVP_PKEY_CTX_set_signature_md";
if (!EVP_PKEY_CTX_set_signature_md(ctx, md))
@@ -566,11 +567,12 @@ err:
* Return: 0 verification good, 1 verification bad, -1 error.
*/
static int verify_hash_v2(void *public_keys, const char *file,
+ const char *hash_algo,
const unsigned char *hash,
int size, unsigned char *sig, int siglen)
{
/* note: signature_v2_hdr does not contain 'type', use sig + 1 */
- return verify_hash_common(public_keys, file, hash, size,
+ return verify_hash_common(public_keys, file, hash_algo, hash, size,
sig + 1, siglen - 1);
}
@@ -581,19 +583,20 @@ static int verify_hash_v2(void *public_keys, const char *file,
* Return: 0 verification good, 1 verification bad, -1 error.
*/
static int verify_hash_v3(void *public_keys, const char *file,
+ const char *hash_algo,
const unsigned char *hash,
int size, unsigned char *sig, int siglen)
{
unsigned char sigv3_hash[MAX_DIGEST_SIZE];
int ret;
- ret = calc_hash_sigv3(sig[0], NULL, hash, sigv3_hash);
+ ret = calc_hash_sigv3(sig[0], hash_algo, hash, sigv3_hash);
if (ret < 0)
return ret;
/* note: signature_v2_hdr does not contain 'type', use sig + 1 */
- return verify_hash_common(public_keys, file, sigv3_hash, size,
- sig + 1, siglen - 1);
+ return verify_hash_common(public_keys, file, hash_algo, sigv3_hash,
+ size, sig + 1, siglen - 1);
}
#define HASH_MAX_DIGESTSIZE 64 /* kernel HASH_MAX_DIGESTSIZE is 64 bytes */
@@ -636,8 +639,10 @@ int calc_hash_sigv3(enum evm_ima_xattr_type type, const char *algo,
return -EINVAL;
}
- if (!algo)
- algo = imaevm_params.hash_algo;
+ if (!algo) {
+ log_err("Hash algorithm unspecified\n");
+ return -EINVAL;
+ }
if ((hash_algo = imaevm_get_hash_algo(algo)) < 0) {
log_err("Hash algorithm %s not supported\n", algo);
@@ -757,10 +762,10 @@ int verify_hash2(void *public_keys, const char *file, const char *hash_algo,
return -1;
#endif
} else if (sig[1] == DIGSIG_VERSION_2) {
- return verify_hash_v2(public_keys, file, hash, size,
+ return verify_hash_v2(public_keys, file, hash_algo, hash, size,
sig, siglen);
} else if (sig[1] == DIGSIG_VERSION_3) {
- return verify_hash_v3(public_keys, file, hash, size,
+ return verify_hash_v3(public_keys, file, hash_algo, hash, size,
sig, siglen);
} else
return -1;
@@ -774,7 +779,8 @@ int verify_hash2(void *public_keys, const char *file, const char *hash_algo,
int verify_hash(const char *file, const unsigned char *hash, int size,
unsigned char *sig, int siglen)
{
- return verify_hash2(g_public_keys, file, NULL, hash, size, sig, siglen);
+ return verify_hash2(g_public_keys, file, imaevm_params.hash_algo,
+ hash, size, sig, siglen);
