Commit 0cefa0f9 authored by Dr. Stephen Henson's avatar Dr. Stephen Henson
Browse files

PR: 2229 

Submitted By: Robin Seggelmann <seggelmann@fh-muenster.de>

Don't drop DTLS connection if mac or decryption failed.
parent 834c85ef

ssl/d1_pkt.c

+11 −16
Original line number Diff line number Diff line
@@ -377,7 +377,7 @@ dtls1_process_record(SSL *s) 
			goto err;



		/* otherwise enc_err == -1 */

		goto decryption_failed_or_bad_record_mac;

		goto err;

		}



#ifdef TLS_DEBUG
@@ -403,7 +403,7 @@ if ( (sess == NULL) || 
			SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);

			goto f_err;

#else

			goto decryption_failed_or_bad_record_mac;

			goto err;

#endif			

			}

		/* check the MAC for rr->input (it's in mac_size bytes at the tail) */
@@ -414,14 +414,14 @@ if ( (sess == NULL) || 
			SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_LENGTH_TOO_SHORT);

			goto f_err;

#else

			goto decryption_failed_or_bad_record_mac;

			goto err;

#endif

			}

		rr->length-=mac_size;

		i=s->method->ssl3_enc->mac(s,md,0);

		if (memcmp(md,&(rr->data[rr->length]),mac_size) != 0)

			{

			goto decryption_failed_or_bad_record_mac;

			goto err;

			}

		}
@@ -463,14 +463,6 @@ if ( (sess == NULL) || 
    dtls1_record_bitmap_update(s, &(s->d1->bitmap));/* Mark receipt of record. */

    return(1);



decryption_failed_or_bad_record_mac:

	/* Separate 'decryption_failed' alert was introduced with TLS 1.0,

	 * SSL 3.0 only has 'bad_record_mac'.  But unless a decryption

	 * failure is directly visible from the ciphertext anyway,

	 * we should not reveal which kind of error occured -- this

	 * might become visible to an attacker (e.g. via logfile) */

	al=SSL_AD_BAD_RECORD_MAC;

	SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);

f_err:

	ssl3_send_alert(s,SSL3_AL_FATAL,al);

err:
@@ -503,8 +495,7 @@ int dtls1_get_record(SSL *s) 


    /* The epoch may have changed.  If so, process all the

     * pending records.  This is a non-blocking operation. */

    if ( ! dtls1_process_buffered_records(s))

        return 0;

    dtls1_process_buffered_records(s);



	/* if we're renegotiating, then there may be buffered records */

	if (dtls1_get_processed_record(s))
@@ -642,7 +633,11 @@ again: 
        }



    if (!dtls1_process_record(s))

        return(0);

		{

		rr->length = 0;

		s->packet_length=0; /* dump this record */

		goto again;     /* get another record */

		}



	dtls1_clear_timeouts(s);  /* done waiting */

	return(1);