I have a linux-box doing NAT and I have tried to setup ip_conntrack_sip
to be able to dynamicly use soft-phones from inside the NAT.
However, it seems that there *might* be a bug when the RTCP connections.
This prevents me from using the cheap (and nerdy) musimi.dk as my VoIP
provider :(
I get an INVITE from 87.54.25.114, with Connection Information "IN IP4
87.54.25.116", and without ip_conntrack_sip the Receiver report goes to
87.54.25.116, but with ip_conntrack_sip it goes to 87.54.25.114 (the SIP
conversation address)
I have included the relevant wireshark dumps of the relevant packages below.
I have complete logs of all network traffic, including the login process
if that's interesting?
=============== Without ip_conntrack_sip: ==============================
----------------- The INVITE -------------------------------------------
--- connect-info + media-description on G.711U: 87.54.25.116 port 12126:
No. Time Source Destination Protocol
Info
188 27.955558 87.54.25.114 85.81.159.186 SIP/SDP
Request: INVITE
sip:36947299@xxxxxxxxxxxxx:20280;rinstance=a731cc86fcd93577, with
session description
Frame 188 (918 bytes on wire, 918 bytes captured)
Arrival Time: Nov 15, 2006 19:25:43.645522000
[Time delta from previous packet: 0.645775000 seconds]
[Time since reference or first frame: 27.955558000 seconds]
Frame Number: 188
Packet Length: 918 bytes
Capture Length: 918 bytes
[Frame is marked: False]
[Protocols in frame: sll:ip:udp:sip:sdp]
[Coloring Rule Name: UDP]
[Coloring Rule String: udp]
Linux cooked capture
Packet type: Unicast to us (0)
Link-layer address type: 1
Link-layer address length: 6
Source: ZyxelCom_39:05:7c (00:13:49:39:05:7c)
Protocol: IP (0x0800)
Internet Protocol, Src: 87.54.25.114 (87.54.25.114), Dst: 85.81.159.186
(85.81.159.186)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x10 (DSCP 0x04: Unknown DSCP; ECN: 0x00)
0001 00.. = Differentiated Services Codepoint: Unknown (0x04)
.... ..0. = ECN-Capable Transport (ECT): 0
.... ...0 = ECN-CE: 0
Total Length: 902
Identification: 0x3373 (13171)
Flags: 0x04 (Don't Fragment)
0... = Reserved bit: Not set
.1.. = Don't fragment: Set
..0. = More fragments: Not set
Fragment offset: 0
Time to live: 58
Protocol: UDP (0x11)
Header checksum: 0xa430 [correct]
[Good: True]
[Bad : False]
Source: 87.54.25.114 (87.54.25.114)
Destination: 85.81.159.186 (85.81.159.186)
User Datagram Protocol, Src Port: sip (5060), Dst Port: 20280 (20280)
Source port: sip (5060)
Destination port: 20280 (20280)
Length: 882
Checksum: 0x98b8 [correct]
Session Initiation Protocol
Request-Line: INVITE
sip:36947299@xxxxxxxxxxxxx:20280;rinstance=a731cc86fcd93577 SIP/2.0
Method: INVITE
[Resent Packet: False]
Message Header
Record-Route: <sip:87.54.25.114;ftag=as53044165;lr=on>
Via: SIP/2.0/UDP 87.54.25.114;branch=z9hG4bK0048.4001de5.0
Transport: UDP
Sent-by Address: 87.54.25.114
Branch: z9hG4bK0048.4001de5.0
Via: SIP/2.0/UDP 87.54.25.116:5060;branch=z9hG4bK6567a86f;rport=5060
Transport: UDP
Sent-by Address: 87.54.25.116
Sent-by port: 5060
Branch: z9hG4bK6567a86f
RPort: 5060
From: "60355070" <sip:60355070@xxxxxxxxxxxx>;tag=as53044165
SIP Display info: "60355070"
SIP from address: sip:60355070@xxxxxxxxxxxx
SIP tag: as53044165
To: <sip:36947299@xxxxxxxxx>
SIP to address: sip:36947299@xxxxxxxxx
Contact: <sip:60355070@xxxxxxxxxxxx>
Contact Binding: <sip:60355070@xxxxxxxxxxxx>
URI: <sip:60355070@xxxxxxxxxxxx>
SIP contact address: sip:60355070@xxxxxxxxxxxx
Call-ID: 41ca659a1dba51e54c56c65e253db961@xxxxxxxxxxxx
CSeq: 102 INVITE
Sequence Number: 102
Method: INVITE
User-Agent: no
Max-Forwards: 16
Date: Wed, 15 Nov 2006 18:25:41 GMT
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY
Content-Type: application/sdp
Content-Length: 216
Message body
Session Description Protocol
Session Description Protocol Version (v): 0
Owner/Creator, Session Id (o): root 21804 21804 IN IP4
87.54.25.116
Owner Username: root
Session ID: 21804
Session Version: 21804
Owner Network Type: IN
Owner Address Type: IP4
Owner Address: 87.54.25.116
Session Name (s): session
Connection Information (c): IN IP4 87.54.25.116
Connection Network Type: IN
Connection Address Type: IP4
Connection Address: 87.54.25.116
Time Description, active time (t): 0 0
Session Start Time: 0
Session Stop Time: 0
Media Description, name and address (m): audio 12126 RTP/AVP
0 101
Media Type: audio
Media Port: 12126
Media Proto: RTP/AVP
Media Format: ITU-T G.711 PCMU
Media Format: 101
Media Attribute (a): rtpmap:0 PCMU/8000
Media Attribute Fieldname: rtpmap
Media Format: 0
MIME Type: PCMU
Media Attribute (a): rtpmap:101 telephone-event/8000
Media Attribute Fieldname: rtpmap
Media Format: 101
MIME Type: telephone-event
Media Attribute (a): fmtp:101 0-16
Media Attribute Fieldname: fmtp
Media Format: 101 [telephone-event]
Media format specific parameters: 0-16
Media Attribute (a): silenceSupp:off - - - -
Media Attribute Fieldname: silenceSupp
Media Attribute Value: off - - - -
----------------- RTCP: Receiver report --------------------------------
--- sending to 87.54.25.116, port 12127
No. Time Source Destination Protocol
Info
219 31.841460 85.81.159.186 87.54.25.116 RTCP
Receiver Report
Frame 219 (176 bytes on wire, 176 bytes captured)
Arrival Time: Nov 15, 2006 19:25:47.531424000
[Time delta from previous packet: 3.777827000 seconds]
[Time since reference or first frame: 31.841460000 seconds]
Frame Number: 219
Packet Length: 176 bytes
Capture Length: 176 bytes
[Frame is marked: False]
[Protocols in frame: sll:ip:udp:rtcp]
[Coloring Rule Name: UDP]
[Coloring Rule String: udp]
Linux cooked capture
Packet type: Sent by us (4)
Link-layer address type: 1
Link-layer address length: 6
Source: Micro-St_c5:d2:d3 (00:11:09:c5:d2:d3)
Protocol: IP (0x0800)
Internet Protocol, Src: 85.81.159.186 (85.81.159.186), Dst: 87.54.25.116
(87.54.25.116)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)
0000 00.. = Differentiated Services Codepoint: Default (0x00)
.... ..0. = ECN-Capable Transport (ECT): 0
.... ...0 = ECN-CE: 0
Total Length: 160
Identification: 0x5de6 (24038)
Flags: 0x00
0... = Reserved bit: Not set
.0.. = Don't fragment: Not set
..0. = More fragments: Not set
Fragment offset: 0
Time to live: 127
Protocol: UDP (0x11)
Header checksum: 0x77b1 [correct]
[Good: True]
[Bad : False]
Source: 85.81.159.186 (85.81.159.186)
Destination: 87.54.25.116 (87.54.25.116)
User Datagram Protocol, Src Port: 36929 (36929), Dst Port: 12127 (12127)
Source port: 36929 (36929)
Destination port: 12127 (12127)
Length: 140
Checksum: 0x3dd7 [correct]
Real-time Transport Control Protocol (Receiver Report)
[Stream setup by SDP (frame 188)]
[Setup frame: 188]
[Setup Method: SDP]
10.. .... = Version: RFC 1889 Version (2)
..0. .... = Padding: False
...0 0000 = Reception report count: 0
Packet type: Receiver Report (201)
Length: 1
Sender SSRC: 1876760333
Real-time Transport Control Protocol (Source description)
[Stream setup by SDP (frame 188)]
[Setup frame: 188]
[Setup Method: SDP]
10.. .... = Version: RFC 1889 Version (2)
..0. .... = Padding: False
...0 0001 = Source count: 1
Packet type: Source description (202)
Length: 30
Chunk 1, SSRC/CSRC 1876760333
Identifier: 1876760333
SDES items
Type: CNAME (user and domain) (1)
Length: 61
Text:
F285ED51A1B74A3E9C04998FB60E9D59@xxxxxxxxxxxxxxxxxxxxxxxxxxxx
Type: PRIV (private extensions) (8)
Length: 49
Prefix length: 16
Prefix string: x-rtp-session-id
Text: 5610AC4508CD44F5A132528BD583BB85
Type: END (0)
[RTCP frame length check: OK - 132 bytes]
=============== With ip_conntrack_sip: ==============================
----------------- The INVITE -------------------------------------------
--- connect-info + media-description on G.711U: 87.54.25.116 port 15878:
No. Time Source Destination Protocol
Info
833 27.893913 87.54.25.114 85.81.159.186 SIP/SDP
Request: INVITE
sip:36947299@xxxxxxxxxxxxx:31656;rinstance=7800be4d6c7e0465, with
session description
Frame 833 (918 bytes on wire, 918 bytes captured)
Arrival Time: Nov 15, 2006 18:55:05.084255000
[Time delta from previous packet: 11.191292000 seconds]
[Time since reference or first frame: 27.893913000 seconds]
Frame Number: 833
Packet Length: 918 bytes
Capture Length: 918 bytes
[Frame is marked: False]
[Protocols in frame: sll:ip:udp:sip:sdp]
[Coloring Rule Name: UDP]
[Coloring Rule String: udp]
Linux cooked capture
Packet type: Unicast to us (0)
Link-layer address type: 1
Link-layer address length: 6
Source: ZyxelCom_39:05:7c (00:13:49:39:05:7c)
Protocol: IP (0x0800)
Internet Protocol, Src: 87.54.25.114 (87.54.25.114), Dst: 85.81.159.186
(85.81.159.186)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x10 (DSCP 0x04: Unknown DSCP; ECN: 0x00)
0001 00.. = Differentiated Services Codepoint: Unknown (0x04)
.... ..0. = ECN-Capable Transport (ECT): 0
.... ...0 = ECN-CE: 0
Total Length: 902
Identification: 0x4388 (17288)
Flags: 0x04 (Don't Fragment)
0... = Reserved bit: Not set
.1.. = Don't fragment: Set
..0. = More fragments: Not set
Fragment offset: 0
Time to live: 58
Protocol: UDP (0x11)
Header checksum: 0x941b [correct]
[Good: True]
[Bad : False]
Source: 87.54.25.114 (87.54.25.114)
Destination: 85.81.159.186 (85.81.159.186)
User Datagram Protocol, Src Port: sip (5060), Dst Port: 31656 (31656)
Source port: sip (5060)
Destination port: 31656 (31656)
Length: 882
Checksum: 0xe61a [correct]
Session Initiation Protocol
Request-Line: INVITE
sip:36947299@xxxxxxxxxxxxx:31656;rinstance=7800be4d6c7e0465 SIP/2.0
Method: INVITE
[Resent Packet: False]
Message Header
Record-Route: <sip:87.54.25.114;ftag=as3e9c7ff3;lr=on>
Via: SIP/2.0/UDP 87.54.25.114;branch=z9hG4bKcc6.4c2d1a85.0
Transport: UDP
Sent-by Address: 87.54.25.114
Branch: z9hG4bKcc6.4c2d1a85.0
Via: SIP/2.0/UDP 87.54.25.116:5060;branch=z9hG4bK4f89e199;rport=5060
Transport: UDP
Sent-by Address: 87.54.25.116
Sent-by port: 5060
Branch: z9hG4bK4f89e199
RPort: 5060
From: "60355070" <sip:60355070@xxxxxxxxxxxx>;tag=as3e9c7ff3
SIP Display info: "60355070"
SIP from address: sip:60355070@xxxxxxxxxxxx
SIP tag: as3e9c7ff3
To: <sip:36947299@xxxxxxxxx>
SIP to address: sip:36947299@xxxxxxxxx
Contact: <sip:60355070@xxxxxxxxxxxx>
Contact Binding: <sip:60355070@xxxxxxxxxxxx>
URI: <sip:60355070@xxxxxxxxxxxx>
SIP contact address: sip:60355070@xxxxxxxxxxxx
Call-ID: 60585ef575856ea834ba3fc52b145034@xxxxxxxxxxxx
CSeq: 102 INVITE
Sequence Number: 102
Method: INVITE
User-Agent: no
Max-Forwards: 16
Date: Wed, 15 Nov 2006 17:55:02 GMT
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY
Content-Type: application/sdp
Content-Length: 216
Message body
Session Description Protocol
Session Description Protocol Version (v): 0
Owner/Creator, Session Id (o): root 18984 18984 IN IP4
87.54.25.116
Owner Username: root
Session ID: 18984
Session Version: 18984
Owner Network Type: IN
Owner Address Type: IP4
Owner Address: 87.54.25.116
Session Name (s): session
Connection Information (c): IN IP4 87.54.25.116
Connection Network Type: IN
Connection Address Type: IP4
Connection Address: 87.54.25.116
Time Description, active time (t): 0 0
Session Start Time: 0
Session Stop Time: 0
Media Description, name and address (m): audio 15878 RTP/AVP
0 101
Media Type: audio
Media Port: 15878
Media Proto: RTP/AVP
Media Format: ITU-T G.711 PCMU
Media Format: 101
Media Attribute (a): rtpmap:0 PCMU/8000
Media Attribute Fieldname: rtpmap
Media Format: 0
MIME Type: PCMU
Media Attribute (a): rtpmap:101 telephone-event/8000
Media Attribute Fieldname: rtpmap
Media Format: 101
MIME Type: telephone-event
Media Attribute (a): fmtp:101 0-16
Media Attribute Fieldname: fmtp
Media Format: 101 [telephone-event]
Media format specific parameters: 0-16
Media Attribute (a): silenceSupp:off - - - -
Media Attribute Fieldname: silenceSupp
Media Attribute Value: off - - - -
----------------- RTCP: Receiver report --------------------------------
--- sending to 87.54.25.114, port 15879
--- expected 87.54.25.116 (not 114)
No. Time Source Destination Protocol
Info
1463 31.828032 85.81.159.186 87.54.25.114 RTCP
Receiver Report
Frame 1463 (176 bytes on wire, 176 bytes captured)
Arrival Time: Nov 15, 2006 18:55:09.018374000
[Time delta from previous packet: 3.810211000 seconds]
[Time since reference or first frame: 31.828032000 seconds]
Frame Number: 1463
Packet Length: 176 bytes
Capture Length: 176 bytes
[Frame is marked: False]
[Protocols in frame: sll:ip:udp:rtcp]
[Coloring Rule Name: UDP]
[Coloring Rule String: udp]
Linux cooked capture
Packet type: Sent by us (4)
Link-layer address type: 1
Link-layer address length: 6
Source: Micro-St_c5:d2:d3 (00:11:09:c5:d2:d3)
Protocol: IP (0x0800)
Internet Protocol, Src: 85.81.159.186 (85.81.159.186), Dst: 87.54.25.114
(87.54.25.114)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)
0000 00.. = Differentiated Services Codepoint: Default (0x00)
.... ..0. = ECN-Capable Transport (ECT): 0
.... ...0 = ECN-CE: 0
Total Length: 160
Identification: 0xb74c (46924)
Flags: 0x00
0... = Reserved bit: Not set
.0.. = Don't fragment: Not set
..0. = More fragments: Not set
Fragment offset: 0
Time to live: 127
Protocol: UDP (0x11)
Header checksum: 0x1e4d [correct]
[Good: True]
[Bad : False]
Source: 85.81.159.186 (85.81.159.186)
Destination: 87.54.25.114 (87.54.25.114)
User Datagram Protocol, Src Port: 22299 (22299), Dst Port: 15879 (15879)
Source port: 22299 (22299)
Destination port: 15879 (15879)
Length: 140
Checksum: 0xc12e [correct]
Real-time Transport Control Protocol (Receiver Report)
[Stream setup by SDP (frame 1464)]
[Setup frame: 1464]
[Setup Method: SDP]
10.. .... = Version: RFC 1889 Version (2)
..0. .... = Padding: False
...0 0000 = Reception report count: 0
Packet type: Receiver Report (201)
Length: 1
Sender SSRC: 1083641640
Real-time Transport Control Protocol (Source description)
[Stream setup by SDP (frame 1464)]
[Setup frame: 1464]
[Setup Method: SDP]
10.. .... = Version: RFC 1889 Version (2)
..0. .... = Padding: False
...0 0001 = Source count: 1
Packet type: Source description (202)
Length: 30
Chunk 1, SSRC/CSRC 1083641640
Identifier: 1083641640
SDES items
Type: CNAME (user and domain) (1)
Length: 61
Text:
FF3B86667EA64176BE3BF27E491AB9DA@xxxxxxxxxxxxxxxxxxxxxxxxxxxx
Type: PRIV (private extensions) (8)
Length: 49
Prefix length: 16
Prefix string: x-rtp-session-id
Text: 109CE61BD7264FAAAE5D01DDFF9A430B
Type: END (0)
[RTCP frame length check: OK - 132 bytes]
