Re: [Serusers] SER has problems matching ACKs to replies

Yet another obstacle on the way of proper INVITE-ACK matching for negative replies: some UA might pick up Via parameters from provisional responses and then copy them into ACK.

INV: SIP/2.0/UDP 192.168.1.20:5060 ACK: SIP/2.0/UDP 192.168.1.20:5060;rport=5060;received=193.111.9.22

For example ATA-186 does this with received/rport parameters, so that they don't match with ones from INVITE: (gdb) print t_msg->via1->name $18 = { s = 0x282ed926 "SIP/2.0/UDP 192.168.1.20:5060\r\nFrom: <sip:380442466396@64.180.102.72;user=phone> ;tag=3473403119\r\nTo: <sip:122@64.180.102.72;user=phone>\r\nCall-ID: 3487919719(a)192.168.1.20\r\nCSe q: 2 INVITE\r\nContact: <sip"..., len = 3} (gdb) print p_msg->orig $19 = 0x80d51f8 "ACK sip:122@64.180.102.72;user=phone SIP/2.0\r\nVia: SIP/2.0/UDP 192.168.1.20:5060; rport=5060;received=193.111.9.226\r\nFrom: <sip:380442466396@64.180.102.72;user=phone>;tag=347340311 9\r\nTo: <sip:122@64.18"... As you can see, in the INVITE we had 1st Via: SIP/2.0/UDP 192.168.1.20:5060 While in the ACK: SIP/2.0/UDP 192.168.1.20:5060;rport=5060;received=193.111.9.226 Needs to be corrected as well. -Maxim On Tue, Apr 08, 2003 at 07:26:54PM +0300, Maxim Sobolev wrote: > Not only that, but there is also a bug which causes match failure > due to extra space in the ACK, see the gdb session below: > > 0x2a17b904 in t_lookup_request (p_msg=0x80d4c88, leave_new_locked=1) at t_lookup.c:268 > 268 {int b=1; while (b);} > (gdb) s b=0 > (gdb) n > 270 if (!EQ_LEN(callid)) continue; > (gdb) print t_msg->callid->body > $8 = { > s = 0x282ed9b8 &quot;3650497277(a)192.168.1.20\r\nCSeqnCSeq: 2 INVITE\r\nContact: <sip:380442466396@192.168.1. > 20:5060;user=phone;transport=udp>\r\nUser-Agent: Cisco ATA 186 v2.15 ata18x (030401b)\r\nAuthorizat > ion: Digest username=\"3804"..., len = 23} > (gdb) print p_msg->callid->body > $9 = {s = 0x80bdf73 " 3650497277(a)192.168.1.20\r&quot;quot;, len = 24} > > As you can see, the callid is the same, but EQ_LEN(callid) will be > false, due to the fact that p_msg->callid->body.len != t_msg->callid->body.len. > > -Maxim > > On Tue, Apr 08, 2003 at 05:56:17PM +0300, Maxim Sobolev wrote: > > Sorry, further investigation shown that this particular problem was > > caused by the typo in our fix for hashing function (one found in 0.8.10 > > didn't bother to strip insignificant chars from call-id and cseq number). > > I've fixed that and the problem gone. > > > > However, we have another problem with ACK matching. The problem is that > > we are using propiertary module which queries billing engine via Radius > > and uses its replies to rewrite URI. Since it isn't practical to run > > that query on each request received, we are only performing it on > > INVITEs, which is fine as long as the next hop is always B2BUA that > > only cares about method URI in INVITE requests and ignores it in any > > subsequent requests. The typical sequence looks like the following: > > > > 1. ATA->SER: > > > > INVITE xyz(a)foo.bar > > > > 2. SER->BILLING > > > > please expand xyz > > > > 3. BILLING->SER > > > > xyz expands to 123456 > > > > 4. SER->B2BUA (t_relay_to()) > > > > INVITE 123456(a)foo.bar > > > > Everything is fine when INVITE transaction ends with a 200 OK, in this > > case ATA generates ACK to acknowelege 200 OK using information from > > that 200 OK, i.e. `ACK 123456(a)foo.bar&#39;#39;, not `ACK xyz(a)foo.bar&#39;#39;. The problem > > happens if transaction ends with 4xx error, or is cancelled by the > > originating party, in this case ATA acknoweleges receipt of final negative > > response with `ACK xyz(a)foo.bar&#39; so that tm module is unable to match ACK > > to original INVITE. > > > > Do you have any ideas how to properly solve this problem without > > introducing steps (2) and (3) above for every ACK request as well? > > It would be inacceptable for us since each BILLING query means > > extra database access, therefore is puting extra load on the system > > and degrading its performance (normal call involves 2 ACKs, so that > > there would be 3 db accesses instead of 1). > > > > I think that it should be possible to resolve the problem by modifying > > tm module to match ACKs for non-200 replies to original uri in INVITE > > instead to rewriten one. What do you think? Is there any potential > > problems with this approach? > > > > -Maxim > > > > On Mon, Apr 07, 2003 at 10:41:31PM +0200, Jiri Kuthan wrote: > > > Maxim, > > > > > > neither did I find a reason why the ACK is not matched. I might be > > > wrong but my guess is that it is a config issue -- are you sure it > > > enters t_relay in your script? > > > > > > -Jiri > > > > > > At 09:19 PM 4/7/2003, Maxim Sobolev wrote: > > > >Folks, > > > > > > > >I found that in the stateful mode, SER is having troubles matching > > > >ACKs to negative replies when Vovida B2BUA (1.5.0) is used as one > > > >UA, while Cisco ATA 186 as another one. Following is a dump of the > > > >session illustrating the problem. As you can see, SER keeps > > > >retransmiting 480, despite receiving properly formed ACKs. Does > > > >anybody have any ideas what the problem might be? > > > > > > > >-Maxim > > > >P.S. I am also seeing in the logs the following warnings: > > > > > > > >Apr 7 12:05:28 demo ser[86090]: WARNING: sip_msg_cloner: header body ignored: 4096 > > > > > > > > > > > >B2BUA->SER > > > > > > > >INVITE sip:16045215277@demo.portaone.com:5060;transport=udp;user=phone SIP/2.0 > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >To: <sip:121@64.180.102.72;user=phone> > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >cisco-GUID: 200546447-2237180178-1764455078-2518034476 > > > >CSeq: 2 INVITE > > > >Max-Forwards: 10 > > > >Expires: 300 > > > >Contact: <sip:380442466396@64.180.102.72:5061;user=phone> > > > >User-Agent: PortaSIP (030401b) > > > >Content-Type: application/sdp > > > >Content-Length: 309 > > > >o=380442466396 20916528 20916528 IN IP4 192.168.1.20 > > > >s=ATA186 Call > > > >c=IN IP4 193.111.9.226 > > > >t=0 0 > > > >m=audio 14000 RTP/AVP 4 8 0 101 > > > >a=rtpmap:4 G723/8000/1 > > > >a=rtpmap:8 PCMA/8000/1 > > > >a=rtpmap:0 PCMU/8000/1 > > > >a=rtpmap:101 telephone-event/8000 > > > >a=fmtp:101 0-15 > > > >a=direction:active > > > >a=oldmediaip:192.168.1.20 > > > > > > > >SER->B2BUA > > > > > > > >SIP/2.0 100 trying -- your call is important to us > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >To: <sip:121@64.180.102.72;user=phone> > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >CSeq: 2 INVITE > > > >Server: Sip EXpress router (0.8.10 (i386/freebsd)) > > > >Content-Length: 0 > > > > > > > >SER->ATA > > > > > > > >INVITE sip:16045215277@172.17.1.127:5060;user=phone;transport=udp SIP/2.0 > > > >Record-Route: <sip:16045215277@64.180.102.72;branch=0> > > > >Via: SIP/2.0/UDP 64.180.102.72;branch=z9hG4bK56f9.3c3c97acad0bdb329284be13e26ccc54.0 > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >To: <sip:121@64.180.102.72;user=phone> > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >cisco-GUID: 200546447-2237180178-1764455078-2518034476 > > > >CSeq: 2 INVITE > > > >Max-Forwards: 9 > > > >Expires: 300 > > > >Contact: <sip:380442466396@64.180.102.72:5061;user=phone> > > > >User-Agent: PortaSIP (030401b) > > > >Content-Type: application/sdp > > > >Content-Length: 309 > > > >o=380442466396 20916528 20916528 IN IP4 192.168.1.20 > > > >s=ATA186 Call > > > >c=IN IP4 193.111.9.226 > > > >t=0 0 > > > >m=audio 14000 RTP/AVP 4 8 0 101 > > > >a=rtpmap:4 G723/8000/1 > > > >a=rtpmap:8 PCMA/8000/1 > > > >a=rtpmap:0 PCMU/8000/1 > > > >a=rtpmap:101 telephone-event/8000 > > > >a=fmtp:101 0-15 > > > >a=direction:active > > > >a=oldmediaip:192.168.1.20 > > > > > > > >ATA->SER > > > > > > > >SIP/2.0 100 Trying > > > >Via: SIP/2.0/UDP 64.180.102.72;branch=z9hG4bK56f9.3c3c97acad0bdb329284be13e26ccc54.0 > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >CSeq: 2 INVITE > > > >Server: Cisco ATA 186 v2.15 ata18x (030401b) > > > >Content-Length: 0 > > > > > > > >ATA->SER > > > > > > > >SIP/2.0 183 Session Progress > > > >Via: SIP/2.0/UDP 64.180.102.72;branch=z9hG4bK56f9.3c3c97acad0bdb329284be13e26ccc54.0 > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >CSeq: 2 INVITE > > > >Server: Cisco ATA 186 v2.15 ata18x (030401b) > > > >Content-Length: 201 > > > >Content-Type: application/sdp > > > >o=16045215277 1110 1110 IN IP4 172.17.1.127 > > > >s=ATA186 Call > > > >c=IN IP4 64.180.102.72 > > > >t=0 0 > > > >m=audio 10000 RTP/AVP 4 101 > > > >a=rtpmap:4 G723/8000/1 > > > >a=rtpmap:101 telephone-event/8000 > > > >a=fmtp:101 0-15 > > > > > > > >SER->B2BUA > > > > > > > >SIP/2.0 183 Session Progress > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >CSeq: 2 INVITE > > > >Server: Cisco ATA 186 v2.15 ata18x (030401b) > > > >Content-Length: 221 > > > >Content-Type: application/sdp > > > >o=16045215277 1110 1110 IN IP4 172.17.1.127 > > > >s=ATA186 Call > > > >c=IN IP4 64.180.102.72 > > > >t=0 0 > > > >m=audio 10000 RTP/AVP 4 101 > > > >a=rtpmap:4 G723/8000/1 > > > >a=rtpmap:101 telephone-event/8000 > > > >a=fmtp:101 0-15 > > > >a=direction:active > > > > > > > >ATA->SER > > > > > > > >SIP/2.0 480 Temporarily Not Available > > > >Via: SIP/2.0/UDP 64.180.102.72;branch=z9hG4bK56f9.3c3c97acad0bdb329284be13e26ccc54.0 > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >CSeq: 2 INVITE > > > >Server: Cisco ATA 186 v2.15 ata18x (030401b) > > > >Content-Length: 0 > > > > > > > >SER->B2BUA > > > > > > > >SIP/2.0 480 Temporarily Not Available > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >CSeq: 2 INVITE > > > >Server: Cisco ATA 186 v2.15 ata18x (030401b) > > > >Content-Length: 0 > > > > > > > >B2BUA->SER > > > > > > > >ACK sip:16045215277@demo.portaone.com:5060;transport=udp;user=phone SIP/2.0 > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >CSeq: 2 ACK > > > >Max-Forwards: 70 > > > >Content-Length: 0 > > > > > > > >SER->ATA > > > > > > > >ACK sip:16045215277@172.17.1.127:5060;user=phone;transport=udp SIP/2.0 > > > >Via: SIP/2.0/UDP 64.180.102.72;branch=z9hG4bKbc52.5db2fe1211adfdd0d5db3db6e2295344.0 > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >CSeq: 2 ACK > > > >Max-Forwards: 69 > > > >Content-Length: 0 > > > > > > > >SER->B2BUA > > > > > > > >SIP/2.0 480 Temporarily Not Available > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >CSeq: 2 INVITE > > > >Server: Cisco ATA 186 v2.15 ata18x (030401b) > > > >Content-Length: 0 > > > > > > > >B2BUA->SER > > > > > > > >ACK sip:16045215277@demo.portaone.com:5060;transport=udp;user=phone SIP/2.0 > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >CSeq: 2 ACK > > > >Max-Forwards: 70 > > > >Content-Length: 0 > > > > > > > >SER->ATA > > > > > > > >ACK sip:16045215277@172.17.1.127:5060;user=phone;transport=udp SIP/2.0 > > > >Via: SIP/2.0/UDP 64.180.102.72;branch=z9hG4bKbc52.5db2fe1211adfdd0d5db3db6e2295344.0 > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >CSeq: 2 ACK > > > >Max-Forwards: 69 > > > >Content-Length: 0 > > > > > > > >SER->B2BUA > > > > > > > >SIP/2.0 480 Temporarily Not Available > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >CSeq: 2 INVITE > > > >Server: Cisco ATA 186 v2.15 ata18x (030401b) > > > >Content-Length: 0 > > > > > > > >B2BUA->SER > > > > > > > >ACK sip:16045215277@demo.portaone.com:5060;transport=udp;user=phone SIP/2.0 > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >CSeq: 2 ACK > > > >Max-Forwards: 70 > > > >Content-Length: 0 > > > > > > > >SER->ATA > > > > > > > >ACK sip:16045215277@172.17.1.127:5060;user=phone;transport=udp SIP/2.0 > > > >Via: SIP/2.0/UDP 64.180.102.72;branch=z9hG4bKbc52.5db2fe1211adfdd0d5db3db6e2295344.0 > > > >Via: SIP/2.0/UDP 64.180.102.72:5061 > > > >To: <sip:121@64.180.102.72;user=phone>;tag=2698540533 > > > >From: <sip:380442466396@64.180.102.72:5061;user=phone>;tag=4505a91c4165b3ffb1b4df0ff79c2904 > > > >Call-ID: 3135130751(a)192.168.1.20 > > > >CSeq: 2 ACK > > > >Max-Forwards: 69 > > > >Content-Length: 0 > > > > > > > >[the last 3 repeat until timeout hits] > > > >_______________________________________________ > > > >Serusers mailing list > > > &gt;serusers(a)lists.iptel.org > > > >http://lists.iptel.org/mailman/listinfo/serusers > > > > > > -- > > > Jiri Kuthan http://iptel.org/~jiri/ > > _______________________________________________ > > Serusers mailing list > > serusers(a)lists.iptel.org > > http://lists.iptel.org/mailman/listinfo/serusers > _______________________________________________ > Serusers mailing list > 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