make sure we don't write to seed[-1]

2001-06-06 17:15:47 +00:00
parent 7e9547e126
commit 38c3436577
1 changed files with 5 additions and 0 deletions
--- a/crypto/rsa/rsa_oaep.c
+++ b/crypto/rsa/rsa_oaep.c
@@ -94,6 +94,11 @@ int RSA_padding_check_PKCS1_OAEP(unsigned char *to, int tlen,
 	}

    lzero = num - flen;
+    if (lzero < 0)
+    {
+    RSAerr(RSA_F_RSA_PADDING_CHECK_PKCS1_OAEP, RSA_R_OAEP_DECODING_ERROR);
+    return (-1);
+    }
    maskeddb = from - lzero + SHA_DIGEST_LENGTH;
    
    MGF1(seed, SHA_DIGEST_LENGTH, maskeddb, dblen);