From 619298a84dcad59e42062a00b8ffe422a1a38d7c Mon Sep 17 00:00:00 2001
From: John Wimer <john@god.vtic.net>
Date: Fri, 3 Sep 2010 19:25:59 +0000
Subject: [PATCH] Send NAT punching messages to the address specified in the
 Transport: message, if available (RFC 2326, section 12.39), fixes issue 2212.

Patch by John Wimer <john at god vtic net>.

Originally committed as revision 25032 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
 libavformat/os_support.h |  4 ++++
 libavformat/rtsp.c       | 15 ++++++++++++++-
 libavformat/rtsp.h       |  1 +
 3 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/libavformat/os_support.h b/libavformat/os_support.h
index 5c9e81b340..1330d3dc04 100644
--- a/libavformat/os_support.h
+++ b/libavformat/os_support.h
@@ -55,6 +55,10 @@ typedef int socklen_t;
 #define closesocket close
 #endif
 
+#ifndef INET6_ADDRSTRLEN
+#define INET6_ADDRSTRLEN INET_ADDRSTRLEN
+#endif
+
 #if CONFIG_FFSERVER
 #if !HAVE_POLL_H
 typedef unsigned long nfds_t;
diff --git a/libavformat/rtsp.c b/libavformat/rtsp.c
index be3eee6411..4ab2c33489 100644
--- a/libavformat/rtsp.c
+++ b/libavformat/rtsp.c
@@ -701,7 +701,14 @@ static void rtsp_parse_transport(RTSPMessageHeader *reply, const char *p)
                     get_word_sep(buf, sizeof(buf), ";,", &p);
                     get_sockaddr(buf, &th->destination);
                 }
+            } else if (!strcmp(parameter, "source")) {
+                if (*p == '=') {
+                    p++;
+                    get_word_sep(buf, sizeof(buf), ";,", &p);
+                    av_strlcpy(th->source, buf, sizeof(th->source));
+                }
             }
+
             while (*p != ';' && *p != '\0' && *p != ',')
                 p++;
             if (*p == ';')
@@ -1154,9 +1161,15 @@ static int make_setup_request(AVFormatContext *s, const char *host, int port,
         case RTSP_LOWER_TRANSPORT_UDP: {
             char url[1024];
 
-            /* XXX: also use address if specified */
+            /* Use source address if specified */
+            if (reply->transports[0].source[0]) {
+                ff_url_join(url, sizeof(url), "rtp", NULL,
+                            reply->transports[0].source,
+                            reply->transports[0].server_port_min, NULL);
+            } else {
             ff_url_join(url, sizeof(url), "rtp", NULL, host,
                         reply->transports[0].server_port_min, NULL);
+            }
             if (!(rt->server_type == RTSP_SERVER_WMS && i > 1) &&
                 rtp_set_remote_url(rtsp_st->rtp_handle, url) < 0) {
                 err = AVERROR_INVALIDDATA;
diff --git a/libavformat/rtsp.h b/libavformat/rtsp.h
index c6c3972576..c5776187e0 100644
--- a/libavformat/rtsp.h
+++ b/libavformat/rtsp.h
@@ -97,6 +97,7 @@ typedef struct RTSPTransportField {
     int ttl;
 
     struct sockaddr_storage destination; /**< destination IP address */
+    char source[INET6_ADDRSTRLEN + 1]; /**< source IP address */
 
     /** data/packet transport protocol; e.g. RTP or RDT */
     enum RTSPTransport transport;