static int dtls1_buffer_record(SSL *s, record_pqueue *q,
unsigned char *priority);
static int dtls1_process_record(SSL *s);
-static void dtls1_clear_timeouts(SSL *s);
/* copy buffered record into SSL structure */
static int
s->packet_length = rdata->packet_length;
memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
+
+ /* Set proper sequence number for mac calculation */
+ memcpy(&(s->s3->read_sequence[2]), &(rdata->packet[5]), 6);
return(1);
}
item = pqueue_peek(s->d1->unprocessed_rcds.q);
if (item)
{
- DTLS1_RECORD_DATA *rdata;
- rdata = (DTLS1_RECORD_DATA *)item->data;
-
/* Check if epoch is current. */
if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch)
return(1); /* Nothing to do. */
SSL3_RECORD *rr;
unsigned int mac_size;
unsigned char md[EVP_MAX_MD_SIZE];
+ int decryption_failed_or_bad_record_mac = 0;
+ unsigned char *mac = NULL;
rr= &(s->s3->rrec);
enc_err = s->method->ssl3_enc->enc(s,0);
if (enc_err <= 0)
{
- if (enc_err == 0)
- /* SSLerr() and ssl3_send_alert() have been called */
- goto err;
-
- /* otherwise enc_err == -1 */
- goto decryption_failed_or_bad_record_mac;
+ /* To minimize information leaked via timing, we will always
+ * perform all computations before discarding the message.
+ */
+ decryption_failed_or_bad_record_mac = 1;
}
#ifdef TLS_DEBUG
SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
goto f_err;
#else
- goto decryption_failed_or_bad_record_mac;
+ decryption_failed_or_bad_record_mac = 1;
#endif
}
/* check the MAC for rr->input (it's in mac_size bytes at the tail) */
- if (rr->length < mac_size)
+ if (rr->length >= mac_size)
{
-#if 0 /* OK only for stream ciphers */
- al=SSL_AD_DECODE_ERROR;
- SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_LENGTH_TOO_SHORT);
- goto f_err;
-#else
- goto decryption_failed_or_bad_record_mac;
-#endif
+ rr->length -= mac_size;
+ mac = &rr->data[rr->length];
}
- rr->length-=mac_size;
+ else
+ rr->length = 0;
i=s->method->ssl3_enc->mac(s,md,0);
- if (i < 0 || memcmp(md,&(rr->data[rr->length]),mac_size) != 0)
+ if (i < 0 || mac == NULL || CRYPTO_memcmp(md,mac,mac_size) != 0)
{
- goto decryption_failed_or_bad_record_mac;
+ decryption_failed_or_bad_record_mac = 1;
}
}
+ if (decryption_failed_or_bad_record_mac)
+ {
+ /* decryption failed, silently discard message */
+ rr->length = 0;
+ s->packet_length = 0;
+ goto err;
+ }
+
/* r->length is now just compressed */
if (s->expand != 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:
int ssl_major,ssl_minor;
int i,n;
SSL3_RECORD *rr;
- SSL_SESSION *sess;
unsigned char *p = NULL;
unsigned short version;
DTLS1_BITMAP *bitmap;
unsigned int is_next_epoch;
rr= &(s->s3->rrec);
- sess=s->session;
/* 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))
if (rr->length == 0) goto again;
/* If this record is from the next epoch (either HM or ALERT),
- * buffer it since it cannot be processed at this time. Records
- * from the next epoch are marked as received even though they
- * are not processed, so as to prevent any potential resource
- * DoS attack */
+ * and a handshake is currently in progress, buffer it since it
+ * cannot be processed at this time. However, do not buffer
+ * anything while listening.
+ */
if (is_next_epoch)
{
- dtls1_record_bitmap_update(s, bitmap);
- dtls1_buffer_record(s, &(s->d1->unprocessed_rcds), rr->seq_num);
+ if ((SSL_in_init(s) || s->in_handshake) && !s->d1->listen)
+ {
+ dtls1_buffer_record(s, &(s->d1->unprocessed_rcds), rr->seq_num);
+ }
rr->length = 0;
s->packet_length = 0;
goto again;
}
- if ( ! dtls1_process_record(s))
- return(0);
+ if (!dtls1_process_record(s))
+ {
+ rr->length = 0;
+ s->packet_length = 0; /* dump this record */
+ goto again; /* get another record */
+ }
- dtls1_clear_timeouts(s); /* done waiting */
return(1);
}
* buffer the application data for later processing rather
* than dropping the connection.
*/
- dtls1_buffer_record(s, &(s->d1->buffered_app_data), 0);
+ dtls1_buffer_record(s, &(s->d1->buffered_app_data), rr->seq_num);
rr->length = 0;
goto start;
}
*/
if (msg_hdr.type == SSL3_MT_FINISHED)
{
+ if (dtls1_check_timeout_num(s) < 0)
+ return -1;
+
dtls1_retransmit_buffered_messages(s);
rr->length = 0;
goto start;
memset(seq, 0x00, seq_bytes);
}
-
-
-static void
-dtls1_clear_timeouts(SSL *s)
- {
- memset(&(s->d1->timeout), 0x00, sizeof(struct dtls1_timeout_st));
- }
projects / oweals / openssl.git / blobdiff