diff options
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/asymmetric_keys/pkcs7_verify.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/crypto/asymmetric_keys/pkcs7_verify.c b/crypto/asymmetric_keys/pkcs7_verify.c index 11bee67fa9cc..ce49820caa97 100644 --- a/crypto/asymmetric_keys/pkcs7_verify.c +++ b/crypto/asymmetric_keys/pkcs7_verify.c @@ -12,6 +12,7 @@ #include <linux/err.h> #include <linux/asn1.h> #include <crypto/hash.h> +#include <crypto/hash_info.h> #include <crypto/public_key.h> #include "pkcs7_parser.h" @@ -29,6 +30,10 @@ static int pkcs7_digest(struct pkcs7_message *pkcs7, kenter(",%u,%s", sinfo->index, sinfo->sig->hash_algo); + /* The digest was calculated already. */ + if (sig->digest) + return 0; + if (!sinfo->sig->hash_algo) return -ENOPKG; @@ -117,6 +122,34 @@ error_no_desc: return ret; } +int pkcs7_get_digest(struct pkcs7_message *pkcs7, const u8 **buf, u32 *len, + enum hash_algo *hash_algo) +{ + struct pkcs7_signed_info *sinfo = pkcs7->signed_infos; + int i, ret; + + /* + * This function doesn't support messages with more than one signature. + */ + if (sinfo == NULL || sinfo->next != NULL) + return -EBADMSG; + + ret = pkcs7_digest(pkcs7, sinfo); + if (ret) + return ret; + + *buf = sinfo->sig->digest; + *len = sinfo->sig->digest_size; + + for (i = 0; i < HASH_ALGO__LAST; i++) + if (!strcmp(hash_algo_name[i], sinfo->sig->hash_algo)) { + *hash_algo = i; + break; + } + + return 0; +} + /* * Find the key (X.509 certificate) to use to verify a PKCS#7 message. PKCS#7 * uses the issuer's name and the issuing certificate serial number for |