diff options
| -rw-r--r-- | lib/digsig.c | 35 |
1 files changed, 10 insertions, 25 deletions
diff --git a/lib/digsig.c b/lib/digsig.c index 5d840ac64fb1..b67e82c024b3 100644 --- a/lib/digsig.c +++ b/lib/digsig.c @@ -34,14 +34,9 @@ static int pkcs_1_v1_5_decode_emsa(const unsigned char *msg, unsigned long msglen, unsigned long modulus_bitlen, unsigned char *out, - unsigned long *outlen, - int *is_valid) + unsigned long *outlen) { unsigned long modulus_len, ps_len, i; - int result; - - /* default to invalid packet */ - *is_valid = 0; modulus_len = (modulus_bitlen >> 3) + (modulus_bitlen & 7 ? 1 : 0); @@ -50,39 +45,30 @@ static int pkcs_1_v1_5_decode_emsa(const unsigned char *msg, return -EINVAL; /* separate encoded message */ - if ((msg[0] != 0x00) || (msg[1] != (unsigned char)1)) { - result = -EINVAL; - goto bail; - } + if ((msg[0] != 0x00) || (msg[1] != (unsigned char)1)) + return -EINVAL; for (i = 2; i < modulus_len - 1; i++) if (msg[i] != 0xFF) break; /* separator check */ - if (msg[i] != 0) { + if (msg[i] != 0) /* There was no octet with hexadecimal value 0x00 to separate ps from m. */ - result = -EINVAL; - goto bail; - } + return -EINVAL; ps_len = i - 2; if (*outlen < (msglen - (2 + ps_len + 1))) { *outlen = msglen - (2 + ps_len + 1); - result = -EOVERFLOW; - goto bail; + return -EOVERFLOW; } *outlen = (msglen - (2 + ps_len + 1)); memcpy(out, &msg[2 + ps_len + 1], *outlen); - /* valid packet */ - *is_valid = 1; - result = 0; -bail: - return result; + return 0; } /* @@ -96,7 +82,7 @@ static int digsig_verify_rsa(struct key *key, unsigned long len; unsigned long mlen, mblen; unsigned nret, l; - int valid, head, i; + int head, i; unsigned char *out1 = NULL, *out2 = NULL; MPI in = NULL, res = NULL, pkey[2]; uint8_t *p, *datap, *endp; @@ -172,10 +158,9 @@ static int digsig_verify_rsa(struct key *key, memset(out1, 0, head); memcpy(out1 + head, p, l); - err = -EINVAL; - pkcs_1_v1_5_decode_emsa(out1, len, mblen, out2, &len, &valid); + err = pkcs_1_v1_5_decode_emsa(out1, len, mblen, out2, &len); - if (valid && len == hlen) + if (!err && len == hlen) err = memcmp(out2, h, hlen); err: |