PR: 2228
[openssl.git] / ssl / d1_pkt.c
index 35e83d8b52dc8e383d60890b861d3c5039873b80..93b3408be53e8024b3c85c88c8215e377df8278a 100644 (file)
@@ -196,6 +196,9 @@ dtls1_copy_record(SSL *s, pitem *item)
     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);
     }
@@ -530,11 +533,11 @@ err:
 /* used only by dtls1_read_bytes */
 int dtls1_get_record(SSL *s)
        {
-       int ssl_major,ssl_minor,al;
+       int ssl_major,ssl_minor;
        int i,n;
        SSL3_RECORD *rr;
        SSL_SESSION *sess;
-       unsigned char *p;
+       unsigned char *p = NULL;
        unsigned short version;
        DTLS1_BITMAP *bitmap;
        unsigned int is_next_epoch;
@@ -561,7 +564,12 @@ again:
                /* read timeout is handled by dtls1_read_bytes */
                if (n <= 0) return(n); /* error or non-blocking */
 
-               OPENSSL_assert(s->packet_length == DTLS1_RT_HEADER_LENGTH);
+               /* this packet contained a partial record, dump it */
+               if (s->packet_length != DTLS1_RT_HEADER_LENGTH)
+                       {
+                       s->packet_length = 0;
+                       goto again;
+                       }
 
                s->rstate=SSL_ST_READ_BODY;
 
@@ -586,26 +594,27 @@ again:
                        {
                        if (version != s->version)
                                {
-                               SSLerr(SSL_F_DTLS1_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
-                               /* Send back error using their
-                                * version number :-) */
-                               s->version=version;
-                               al=SSL_AD_PROTOCOL_VERSION;
-                               goto f_err;
+                               /* unexpected version, silently discard */
+                               rr->length = 0;
+                               s->packet_length = 0;
+                               goto again;
                                }
                        }
 
                if ((version & 0xff00) != (s->version & 0xff00))
                        {
-                       SSLerr(SSL_F_DTLS1_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
-                       goto err;
+                       /* wrong version, silently discard record */
+                       rr->length = 0;
+                       s->packet_length = 0;
+                       goto again;
                        }
 
                if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
                        {
-                       al=SSL_AD_RECORD_OVERFLOW;
-                       SSLerr(SSL_F_DTLS1_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
-                       goto f_err;
+                       /* record too long, silently discard it */
+                       rr->length = 0;
+                       s->packet_length = 0;
+                       goto again;
                        }
 
                /* now s->rstate == SSL_ST_READ_BODY */
@@ -642,8 +651,15 @@ again:
                goto again;   /* get another record */
                }
 
-       /* check whether this is a repeat, or aged record */
-       if ( ! dtls1_record_replay_check(s, bitmap))
+       /* Check whether this is a repeat, or aged record.
+        * Don't check if we're listening and this message is
+        * a ClientHello. They can look as if they're replayed,
+        * since they arrive from different connections and
+        * would be dropped unnecessarily.
+        */
+       if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE &&
+               *p == SSL3_MT_CLIENT_HELLO) &&
+               !dtls1_record_replay_check(s, bitmap))
                {
                rr->length = 0;
                s->packet_length=0; /* dump this record */
@@ -654,14 +670,14 @@ again:
        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. */
        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)
+                       {
+                       dtls1_buffer_record(s, &(s->d1->unprocessed_rcds), rr->seq_num);
+                       }
                rr->length = 0;
                s->packet_length = 0;
                goto again;
@@ -673,10 +689,6 @@ again:
        dtls1_clear_timeouts(s);  /* done waiting */
        return(1);
 
-f_err:
-       ssl3_send_alert(s,SSL3_AL_FATAL,al);
-err:
-       return(0);
        }
 
 /* Return up to 'len' payload bytes received in 'type' records.
@@ -771,11 +783,8 @@ start:
                }
 
        /* Check for timeout */
-       if (dtls1_is_timer_expired(s))
-               {
-               if (dtls1_read_failed(s, -1) > 0);
-                       goto start;
-               }
+       if (dtls1_handle_timeout(s) > 0)
+               goto start;
 
        /* get new packet if necessary */
        if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
@@ -803,7 +812,7 @@ start:
                 * 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;
                }
@@ -1258,7 +1267,6 @@ err:
 int
 dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len)
        {
-       unsigned int n,tot;
        int i;
 
        if (SSL_in_init(s) && !s->in_handshake)
@@ -1272,31 +1280,14 @@ dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len)
                        }
                }
 
-       tot = s->s3->wnum;
-       n = len - tot;
-
-       while( n)
+       if (len > SSL3_RT_MAX_PLAIN_LENGTH)
                {
-               /* dtls1_write_bytes sends one record at a time, sized according to 
-                * the currently known MTU */
-               i = dtls1_write_bytes(s, type, buf_, len);
-               if (i <= 0) return i;
-               
-               if ((i == (int)n) ||
-                       (type == SSL3_RT_APPLICATION_DATA &&
-                               (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
-                       {
-                       /* next chunk of data should get another prepended empty fragment
-                        * in ciphersuites with known-IV weakness: */
-                       s->s3->empty_fragment_done = 0;
-                       return tot+i;
-                       }
-
-               tot += i;
-               n-=i;
+                       SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_DTLS_MESSAGE_TOO_BIG);
+                       return -1;
                }
 
-       return tot;
+       i = dtls1_write_bytes(s, type, buf_, len);
+       return i;
        }
 
 
@@ -1337,46 +1328,13 @@ have_handshake_fragment(SSL *s, int type, unsigned char *buf,
 /* Call this to write data in records of type 'type'
  * It will return <= 0 if not all data has been sent or non-blocking IO.
  */
-int dtls1_write_bytes(SSL *s, int type, const void *buf_, int len)
+int dtls1_write_bytes(SSL *s, int type, const void *buf, int len)
        {
-       const unsigned char *buf=buf_;
-       unsigned int tot,n,nw;
        int i;
-       unsigned int mtu;
 
+       OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH);
        s->rwstate=SSL_NOTHING;
-       tot=s->s3->wnum;
-
-       n=(len-tot);
-
-       /* handshake layer figures out MTU for itself, but data records
-        * are also sent through this interface, so need to figure out MTU */
-#if 0
-       mtu = BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_GET_MTU, 0, NULL);
-       mtu += DTLS1_HM_HEADER_LENGTH;  /* HM already inserted */
-#endif
-       mtu = s->d1->mtu;
-
-       if (mtu > SSL3_RT_MAX_PLAIN_LENGTH)
-               mtu = SSL3_RT_MAX_PLAIN_LENGTH;
-
-       if (n > mtu)
-               nw=mtu;
-       else
-               nw=n;
-       
-       i=do_dtls1_write(s, type, &(buf[tot]), nw, 0);
-       if (i <= 0)
-               {
-               s->s3->wnum=tot;
-               return i;
-               }
-
-       if ( (int)s->s3->wnum + i == len)
-               s->s3->wnum = 0;
-       else 
-               s->s3->wnum += i;
-
+       i=do_dtls1_write(s, type, buf, len, 0);
        return i;
        }