Changeset 3028 for pjproject/trunk/pjnath/src/pjnath/turn_sock.c

Timestamp:

Dec 8, 2009 1:11:25 PM (14 years ago)

Author:

bennylp

Message:

Fixed ticket #999:

Several bug fixes to the TURN client library and icedemo sample application:

1. ICE stream transport reports ICE initialization/candidate gathering stage as successful even when TURN client TCP connection has failed.
2. Bad ChannelData? framing when TCP is used. PJNATH did not properly add padding to the TURN ChannelData? packet if TCP is used and the data is not aligned to four bytes boundary. Similarly incoming ChannelData? with padding (over TCP) may not be handled correctly.
3. Incoming data over TCP may be delayed. PJNATH only processed one frame (be it request, indication, or ChannelData?) on an incoming stream, so if the stream contains more than one frames, the processing of subsequent frames will be delayed until more stream is received on the TCP transport.
4. The icedemo sample application overwrites the incoming packet buffer with NULL character ('\0') before printing the message to console. If there is another packet after current packet (as often happens when TCP is used), the subsequent packet will get corrupted.

The combinations of bugs above may cause PJNATH to return "Invalid STUN message length (PJNATH_EINSTUNMSGLEN)" error when processing incoming TURN ChannelData? message over TCP.

And a small enhancement:

1. Add logging to file option to icedemo sample.

Thanks Sarun Nandakumar for the report.

File:

• pjproject/trunk/pjnath/src/pjnath/turn_sock.c (modified) (5 diffs)

pjproject/trunk/pjnath/src/pjnath/turn_sock.c

@@ -274 +274 @@
                      pj_status_t status)
 {
-    char errmsg[PJ_ERR_MSG_SIZE];
-
-    if (status != PJ_SUCCESS) {
-        pj_strerror(status, errmsg, sizeof(errmsg));
-        PJ_LOG(4,(turn_sock->obj_name, "%s: %s", title, errmsg));
-    } else {
-        PJ_LOG(4,(turn_sock->obj_name, "%s", title, errmsg));
-    }
+    PJ_PERROR(4,(turn_sock->obj_name, status, title));
 }
 
@@ -289 +282 @@
 {
     show_err(turn_sock, title, status);
-    if (turn_sock->sess)
-        pj_turn_session_destroy(turn_sock->sess);
+    if (turn_sock->sess) {
+        pj_turn_session_destroy(turn_sock->sess, status);
+    }
 }
 
@@ -495 +489 @@
 }
 
+static pj_uint16_t GETVAL16H(const pj_uint8_t *buf, unsigned pos)
+{
+    return (pj_uint16_t) ((buf[pos + 0] << 8) | \
+                          (buf[pos + 1] << 0));
+}
+
+/* Quick check to determine if there is enough packet to process in the
+ * incoming buffer. Return the packet length, or zero if there's no packet.
+ */
+static unsigned has_packet(pj_turn_sock *turn_sock, const void *buf, pj_size_t bufsize)
+{
+    pj_bool_t is_stun;
+
+    if (turn_sock->conn_type == PJ_TURN_TP_UDP)
+        return bufsize;
+
+    /* Quickly check if this is STUN message, by checking the first two bits and
+     * size field which must be multiple of 4 bytes
+     */
+    is_stun = ((((pj_uint8_t*)buf)[0] & 0xC0) == 0) &&
+              ((GETVAL16H((const pj_uint8_t*)buf, 2) & 0x03)==0);
+
+    if (is_stun) {
+        pj_size_t msg_len = GETVAL16H((const pj_uint8_t*)buf, 2);
+        return (msg_len+20 <= bufsize) ? msg_len+20 : 0;
+    } else {
+        /* This must be ChannelData. */
+        pj_turn_channel_data cd;
+
+        if (bufsize < 4)
+            return 0;
+
+        /* Decode ChannelData packet */
+        pj_memcpy(&cd, buf, sizeof(pj_turn_channel_data));
+        cd.length = pj_ntohs(cd.length);
+
+        if (bufsize >= cd.length+sizeof(cd)) 
+            return (cd.length+sizeof(cd)+3) & (~3);
+        else
+            return 0;
+    }
+}
+
 /*
  * Notification from ioqueue when incoming UDP packet is received.
@@ -505 +542 @@
 {
     pj_turn_sock *turn_sock;
-    pj_size_t parsed_len;
     pj_bool_t ret = PJ_TRUE;
 
@@ -512 +548 @@
 
     if (status == PJ_SUCCESS && turn_sock->sess) {
-        /* Report incoming packet to TURN session */
-        parsed_len = (unsigned)size;
-        pj_turn_session_on_rx_pkt(turn_sock->sess, data,  size, &parsed_len);
-        if (parsed_len < (unsigned)size) {
-            *remainder = size - parsed_len;
-            pj_memmove(data, ((char*)data)+parsed_len, *remainder);
-        } else {
-            *remainder = 0;
+        /* Report incoming packet to TURN session, repeat while we have
+         * "packet" in the buffer (required for stream-oriented transports)
+         */
+        unsigned pkt_len;
+
+        //PJ_LOG(5,(turn_sock->pool->obj_name, 
+        //        "Incoming data, %lu bytes total buffer", size));
+
+        while ((pkt_len=has_packet(turn_sock, data, size)) != 0) {
+            pj_size_t parsed_len;
+            //const pj_uint8_t *pkt = (const pj_uint8_t*)data;
+
+            //PJ_LOG(5,(turn_sock->pool->obj_name, 
+            //        "Packet start: %02X %02X %02X %02X", 
+            //        pkt[0], pkt[1], pkt[2], pkt[3]));
+
+            //PJ_LOG(5,(turn_sock->pool->obj_name, 
+            //        "Processing %lu bytes packet of %lu bytes total buffer",
+            //        pkt_len, size));
+
+            parsed_len = (unsigned)size;
+            pj_turn_session_on_rx_pkt(turn_sock->sess, data,  size, &parsed_len);
+
+            /* parsed_len may be zero if we have parsing error, so use our
+             * previous calculation to exhaust the bad packet.
+             */
+            if (parsed_len == 0)
+                parsed_len = pkt_len;
+
+            if (parsed_len < (unsigned)size) {
+                *remainder = size - parsed_len;
+                pj_memmove(data, ((char*)data)+parsed_len, *remainder);
+            } else {
+                *remainder = 0;
+            }
+            size = *remainder;
+
+            //PJ_LOG(5,(turn_sock->pool->obj_name, 
+            //        "Buffer size now %lu bytes", size));
         }
     } else if (status != PJ_SUCCESS &&