Add error checking to PKCS1_MGF1. From HEAD.

This commit is contained in:
Dr. Stephen Henson 2011-09-01 15:42:38 +00:00
parent 64763ce09b
commit dd3a770e07

View File

@ -189,34 +189,40 @@ int PKCS1_MGF1(unsigned char *mask, long len,
EVP_MD_CTX c;
unsigned char md[EVP_MAX_MD_SIZE];
int mdlen;
int rv = -1;
EVP_MD_CTX_init(&c);
mdlen = EVP_MD_size(dgst);
if (mdlen < 0)
return -1;
goto err;
for (i = 0; outlen < len; i++)
{
cnt[0] = (unsigned char)((i >> 24) & 255);
cnt[1] = (unsigned char)((i >> 16) & 255);
cnt[2] = (unsigned char)((i >> 8)) & 255;
cnt[3] = (unsigned char)(i & 255);
EVP_DigestInit_ex(&c,dgst, NULL);
EVP_DigestUpdate(&c, seed, seedlen);
EVP_DigestUpdate(&c, cnt, 4);
if (!EVP_DigestInit_ex(&c,dgst, NULL)
|| !EVP_DigestUpdate(&c, seed, seedlen)
|| !EVP_DigestUpdate(&c, cnt, 4))
goto err;
if (outlen + mdlen <= len)
{
EVP_DigestFinal_ex(&c, mask + outlen, NULL);
if (!EVP_DigestFinal_ex(&c, mask + outlen, NULL))
goto err;
outlen += mdlen;
}
else
{
EVP_DigestFinal_ex(&c, md, NULL);
if (!EVP_DigestFinal_ex(&c, md, NULL))
goto err;
memcpy(mask + outlen, md, len - outlen);
outlen = len;
}
}
rv = 0;
err:
EVP_MD_CTX_cleanup(&c);
return 0;
return rv;
}
static int MGF1(unsigned char *mask, long len, const unsigned char *seed,