diff options
Diffstat (limited to 'lib/rsa')
| -rw-r--r-- | lib/rsa/rsa-verify.c | 37 |
1 files changed, 18 insertions, 19 deletions
diff --git a/lib/rsa/rsa-verify.c b/lib/rsa/rsa-verify.c index c2c7248f90..de71234cfb 100644 --- a/lib/rsa/rsa-verify.c +++ b/lib/rsa/rsa-verify.c @@ -208,6 +208,10 @@ out: * saltlen:-1 "set the salt length to the digest length" is currently * not supported. * + * msg is a concatenation of : masked_db + h + 0xbc + * Once unmasked, db is a concatenation of : [0x00]* + 0x01 + salt + * Length of 0-padding at begin of db depends on salt length. + * * @info: Specifies key and FIT information * @msg: byte array of message, len equal to msg_len * @msg_len: Message length @@ -218,27 +222,25 @@ int padding_pss_verify(struct image_sign_info *info, const uint8_t *msg, int msg_len, const uint8_t *hash, int hash_len) { - uint8_t *masked_db = NULL; - int masked_db_len = msg_len - hash_len - 1; - uint8_t *h = NULL, *hprime = NULL; - int h_len = hash_len; + const uint8_t *masked_db = NULL; uint8_t *db_mask = NULL; - int db_mask_len = masked_db_len; - uint8_t *db = NULL, *salt = NULL; - int db_len = masked_db_len, salt_len = msg_len - hash_len - 2; + uint8_t *db = NULL; + int db_len = msg_len - hash_len - 1; + const uint8_t *h = NULL; + uint8_t *hprime = NULL; + int h_len = hash_len; + uint8_t *salt = NULL; + int salt_len = msg_len - hash_len - 2; uint8_t pad_zero[8] = { 0 }; int ret, i, leftmost_bits = 1; uint8_t leftmost_mask; struct checksum_algo *checksum = info->checksum; /* first, allocate everything */ - masked_db = malloc(masked_db_len); - h = malloc(h_len); - db_mask = malloc(db_mask_len); + db_mask = malloc(db_len); db = malloc(db_len); - salt = malloc(salt_len); hprime = malloc(hash_len); - if (!masked_db || !h || !db_mask || !db || !salt || !hprime) { + if (!db_mask || !db || !hprime) { printf("%s: can't allocate some buffer\n", __func__); ret = -ENOMEM; goto out; @@ -252,8 +254,8 @@ int padding_pss_verify(struct image_sign_info *info, } /* step 5 */ - memcpy(masked_db, msg, masked_db_len); - memcpy(h, msg + masked_db_len, h_len); + masked_db = &msg[0]; + h = &msg[db_len]; /* step 6 */ leftmost_mask = (0xff >> (8 - leftmost_bits)) << (8 - leftmost_bits); @@ -265,7 +267,7 @@ int padding_pss_verify(struct image_sign_info *info, } /* step 7 */ - mask_generation_function1(checksum, h, h_len, db_mask, db_mask_len); + mask_generation_function1(checksum, h, h_len, db_mask, db_len); /* step 8 */ for (i = 0; i < db_len; i++) @@ -283,7 +285,7 @@ int padding_pss_verify(struct image_sign_info *info, } /* step 11 */ - memcpy(salt, &db[1], salt_len); + salt = &db[1]; /* step 12 & 13 */ compute_hash_prime(checksum, pad_zero, 8, @@ -295,11 +297,8 @@ int padding_pss_verify(struct image_sign_info *info, out: free(hprime); - free(salt); free(db); free(db_mask); - free(h); - free(masked_db); return ret; } |