Add error checking to PKCS1_MGF1. From HEAD.

diff --git a/crypto/rsa/rsa_oaep.c b/crypto/rsa/rsa_oaep.c
index e238d10e5cc6fc517e0a6ce4cb42f453da2552ad..18d307ea9e1d9e4d4cd6c0a238614a5cd3a272ac 100644 (file)
--- a/crypto/rsa/rsa_oaep.c
+++ b/crypto/rsa/rsa_oaep.c
@@ -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,