res_rtp_multicast: Ensure SSRC is set properly

This fixes a bug where the SSRC field on multicast RTP can be stuck at
0 which can cause problems for endpoints trying to make sense of
incoming streams.

(closes issue ASTERISK-22567)
Reported by: Simone Camporeale
Patches:
    22567_res_mulitcast_ssrc.patch uploaded by Simone Camporeale (License 6536)
........

Merged revisions 400393 from http://svn.asterisk.org/svn/asterisk/branches/1.8

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/11@400394 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/res/res_rtp_multicast.c b/res/res_rtp_multicast.c
index 2b6678d111dbc4f398c4360902e5b2f750a4ea45..c13e9ad1ec9737f35c345bae80caf51e0a8f0b28 100644 (file)
--- a/res/res_rtp_multicast.c
+++ b/res/res_rtp_multicast.c
@@ -260,15 +260,15 @@ static int multicast_rtp_write(struct ast_rtp_instance *instance, struct ast_fra
        /* Construct an RTP header for our packet */
        rtpheader = (unsigned char *)(f->data.ptr - hdrlen);
        put_unaligned_uint32(rtpheader, htonl((2 << 30) | (codec << 16) | (multicast->seqno)));
-       put_unaligned_uint32(rtpheader + 4, htonl(multicast->lastts));
        
        if (ast_test_flag(f, AST_FRFLAG_HAS_TIMING_INFO)) {
                put_unaligned_uint32(rtpheader + 4, htonl(f->ts * 8));
-       } 
-       else {
-               put_unaligned_uint32(rtpheader + 8, htonl(multicast->ssrc));
+       } else {
+               put_unaligned_uint32(rtpheader + 4, htonl(multicast->lastts));
        }
 
+       put_unaligned_uint32(rtpheader + 8, htonl(multicast->ssrc));
+
        /* Increment sequence number and wrap to 0 if it overflows 16 bits. */
        multicast->seqno = 0xFFFF & (multicast->seqno + 1);