diff options
author | Hadriel Kaplan <hadrielk@yahoo.com> | 2014-03-06 17:20:48 -0500 |
---|---|---|
committer | Evan Huus <eapache@gmail.com> | 2014-03-12 17:59:51 +0000 |
commit | c4c83502849ec2e0a2544e494647641d6c16dc4f (patch) | |
tree | a2b0dc165f37afcf6f7c8361b5bdbac903b4fc65 /epan | |
parent | 70ff7be1e6735cd9b00bfeb1c23bf19cf1250c01 (diff) |
Fix bug 9021: 'RTP not decoded inside the conversation in v.1.10.1'
The behavior for SIP/SDP handling of RTP conversation tracking
changed in v1.10, with some unintended consequences. The bugs did not
show up at the time because wireshark makes 2 passes of the packet list,
and so the problems auto-corrected themselves in most cases. Unfortunately,
a change in r53641 modified how UDP behaves, making it always create
conversations for UDP packets, and that exposed the bugs inherent in the
SIP/SDP code changes.
This commit reverts the behavior of SIP/SDP to its pre-1.10 model, but
creates a new preference setting for "Delay SDP changes for tracking media",
which if enabled, will turn on the new (but buggy) model introduced in 1.10.
This preference is *disabled* by default, since for a majority of cases the
new behavior is worse than the previous behavior.
The preference, and this commit's fix, is not intended to last long. I intend
to re-write the SIP/SDP/RTP interaction model for release 1.11 - I think it's
too big a change for 1.10, however, which is why I submitted this commit.
Change-Id: Ic5601749d6c2344e952ced8206dd9296bfdc4b90
Reviewed-on: https://code.wireshark.org/review/543
Reviewed-by: Evan Huus <eapache@gmail.com>
Diffstat (limited to 'epan')
-rw-r--r-- | epan/dissectors/packet-sdp.c | 21 | ||||
-rw-r--r-- | epan/dissectors/packet-sdp.h | 2 | ||||
-rw-r--r-- | epan/dissectors/packet-sip.c | 17 |
3 files changed, 31 insertions, 9 deletions
diff --git a/epan/dissectors/packet-sdp.c b/epan/dissectors/packet-sdp.c index 939b356ce1..d7cbaa62b2 100644 --- a/epan/dissectors/packet-sdp.c +++ b/epan/dissectors/packet-sdp.c @@ -1684,7 +1684,8 @@ convert_disposable_media(transport_info_t* transport_info, disposable_media_info } void -setup_sdp_transport(tvbuff_t *tvb, packet_info *pinfo, enum sdp_exchange_type exchange_type, int request_frame) +setup_sdp_transport(tvbuff_t *tvb, packet_info *pinfo, enum sdp_exchange_type exchange_type, + int request_frame, const gboolean delay) { gint offset = 0, next_offset, n; int linelen; @@ -1736,6 +1737,18 @@ setup_sdp_transport(tvbuff_t *tvb, packet_info *pinfo, enum sdp_exchange_type ex if (transport_info->media_count > 0) start_transport_info_count = transport_info->media_count; + /* if we don't delay, and this is an answer after a previous offer, then + we free'd the unused media rtp_dyn_payload last time while processing + the offer, so we need to re-create them this time in case we need them. + If they don't get used they'll get free'd again later */ + if (!delay && (exchange_type == SDP_EXCHANGE_ANSWER_ACCEPT) && + (transport_info->sdp_status == SDP_EXCHANGE_OFFER)) { + for (n = start_transport_info_count; n < SDP_MAX_RTP_CHANNELS; n++) { + if (!transport_info->media[n].rtp_dyn_payload) + transport_info->media[n].rtp_dyn_payload = g_hash_table_new(g_int_hash, g_int_equal); + } + } + /* * Show the SDP message a line at a time. */ @@ -1815,8 +1828,8 @@ setup_sdp_transport(tvbuff_t *tvb, packet_info *pinfo, enum sdp_exchange_type ex convert_disposable_media(transport_info, &media_info, start_transport_info_count); /* We have a successful negotiation, apply data to their respective protocols */ - if ((exchange_type == SDP_EXCHANGE_ANSWER_ACCEPT) && - (transport_info->sdp_status == SDP_EXCHANGE_OFFER)) { + if (!delay || ((exchange_type == SDP_EXCHANGE_ANSWER_ACCEPT) && + (transport_info->sdp_status == SDP_EXCHANGE_OFFER))) { for (n = 0; n <= transport_info->media_count; n++) { guint32 current_rtp_port = 0; @@ -1920,7 +1933,7 @@ setup_sdp_transport(tvbuff_t *tvb, packet_info *pinfo, enum sdp_exchange_type ex } } } - transport_info->sdp_status = SDP_EXCHANGE_ANSWER_ACCEPT; + transport_info->sdp_status = exchange_type; } else if ((exchange_type == SDP_EXCHANGE_ANSWER_REJECT) && (transport_info->sdp_status != SDP_EXCHANGE_ANSWER_REJECT)) { diff --git a/epan/dissectors/packet-sdp.h b/epan/dissectors/packet-sdp.h index 348ed7906a..7d315496ba 100644 --- a/epan/dissectors/packet-sdp.h +++ b/epan/dissectors/packet-sdp.h @@ -35,7 +35,7 @@ enum sdp_exchange_type SDP_EXCHANGE_ANSWER_REJECT }; -extern void setup_sdp_transport(tvbuff_t *tvb, packet_info *pinfo, enum sdp_exchange_type type, int request_frame); +extern void setup_sdp_transport(tvbuff_t *tvb, packet_info *pinfo, enum sdp_exchange_type type, int request_frame, const gboolean delay); /* Handles duplicate OFFER packets so they don't end up processed by dissect_sdp(). This can probably * be removed when all higher layer dissectors properly handle SDP themselves with setup_sdp_transport() */ diff --git a/epan/dissectors/packet-sip.c b/epan/dissectors/packet-sip.c index 7072d76d40..09bec53be8 100644 --- a/epan/dissectors/packet-sip.c +++ b/epan/dissectors/packet-sip.c @@ -57,7 +57,6 @@ #include "packet-sdp.h" /* SDP needs a transport layer to determine request/response */ - #define TCP_PORT_SIP 5060 #define UDP_PORT_SIP 5060 #define TLS_PORT_SIP 5061 @@ -811,6 +810,9 @@ static gboolean sip_desegment_body = TRUE; */ static gboolean sip_retrans_the_same_sport = TRUE; +/* whether we hold off tracking RTP conversations until an SDP answer is received */ +static gboolean sip_delay_sdp_changes = FALSE; + /* Extension header subdissectors */ static dissector_table_t ext_hdr_subdissector_table; @@ -3506,15 +3508,15 @@ dissect_sip_common(tvbuff_t *tvb, int offset, packet_info *pinfo, proto_tree *tr /* Resends don't count */ if (resend_for_packet == 0) { if (line_type == REQUEST_LINE) { - setup_sdp_transport(next_tvb, pinfo, SDP_EXCHANGE_OFFER, pinfo->fd->num); + setup_sdp_transport(next_tvb, pinfo, SDP_EXCHANGE_OFFER, pinfo->fd->num, sip_delay_sdp_changes); } else if (line_type == STATUS_LINE) { if (stat_info->response_code >= 400) { /* SIP client request failed, so SDP offer should fail */ - setup_sdp_transport(next_tvb, pinfo, SDP_EXCHANGE_ANSWER_REJECT, request_for_response); + setup_sdp_transport(next_tvb, pinfo, SDP_EXCHANGE_ANSWER_REJECT, request_for_response, sip_delay_sdp_changes); } else if ((stat_info->response_code >= 200) && (stat_info->response_code <= 299)) { /* SIP success request, so SDP offer should be accepted */ - setup_sdp_transport(next_tvb, pinfo, SDP_EXCHANGE_ANSWER_ACCEPT, request_for_response); + setup_sdp_transport(next_tvb, pinfo, SDP_EXCHANGE_ANSWER_ACCEPT, request_for_response, sip_delay_sdp_changes); } } } else { @@ -5576,6 +5578,13 @@ void proto_register_sip(void) "Retransmissions always use the same source port", "Whether retransmissions are detected coming from the same source port only.", &sip_retrans_the_same_sport); + prefs_register_bool_preference(sip_module, "delay_sdp_changes", + "Delay SDP changes for tracking media", + "Whether SIP should delay tracking the media (e.g., RTP/RTCP) until an SDP offer " + "is answered. If enabled, mid-dialog changes to SDP and media state only take " + "effect if and when an SDP offer is successfully answered; however enabling this " + "prevents tracking media in early-media call scenarios", + &sip_delay_sdp_changes); prefs_register_obsolete_preference(sip_module, "tcp.port"); |