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Summary:ASTERISK-11439: T.38 Re-Invite header replaced by audio header when SIP asks for authorization
Reporter:Fall Fall (fall)Labels:
Date Opened:2008-02-14 11:46:49.000-0600Date Closed:2008-03-26 14:02:28
Priority:MajorRegression?No
Status:Closed/CompleteComponents:Channels/chan_sip/T.38
Versions:Frequency of
Occurrence
Related
Issues:
Environment:Attachments:( 0) fax2.log
Description:When trying to receive fax from SIP vendor thru Asterisk to SPA3102 with T.38 service, it fails to receive always.
Further analyse found the sip header got replaced with audio codec header in MD5 response in session decription protocol field when SIP vendor replied with 401 unauthorized and asterisk reply with MD5 response.
The packet sequense is like this,
0. channel built by initially invite from SIP to local asterisk with ulaw pcm.
0.5 SPA3102 accept invite and detected fax, reinvite T.38.
1. asterisk reinvite with T.38 to sip vendor in session description protocol
2. sip vendor replied with 401 unauthorized.
3. asterisk replied with ACK.
4. astertisk resend invite with secret MD5 reponse, but with header field replaced with ulaw PCM codec.
5. 200 OK from sip vedor for invite with header ulaw PCM. asterisk reply with ACK.
6. SPA3000 resend T.38 invite to asterisk.
7. asterisk forward T.38 invite to sip vendor again.
8. repeat step 2.
9. repeast step 3
10. repeat step 4
11. repeat step 5

...
repeat step 6-11 until fax machine timeout and reported error.

****** ADDITIONAL INFORMATION ******

It's the same for 1.4.9 and 1.4.16 I tested.
T.38 invite with MD5 reponse (step 4) should contain the same header with T.38 (step 1) NOT audio codec u-law PCM.
Comments:By: Fall Fall (fall) 2008-02-14 12:10:23.000-0600

events continued as
n. sip vendor detected fax signaling and reinvite T.38 because all asterisk initiated invite with qualified MD5 response are all telephone event with ulaw PCM codec. (all invite from * with T.38 didn't have MD5.)
n+1. asterisk ACK and forward to SPA3102.
n+2. SPA3102 will reply with 486 busy here, because T.38 invite from SPA3102 sent at step 0.5 has not responded by proxy asterisk. (because all invite went to sip vendor had T.38 header didn't have MD5 repsonse. All MD5 responded invite from asterisk header were all replaced by telephone event ulaw pcm)
By: Fall Fall (fall) 2008-02-14 12:24:01.000-0600

step 0.5 is around line 454
1 around line 544
2 line 618
4 665
5 708
debug file uploaded
By: Digium Subversion (svnbot) 2008-03-26 14:00:07

Repository: asterisk
Revision: 111020

U   branches/1.4/channels/chan_sip.c

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r111020 | file | 2008-03-26 14:00:04 -0500 (Wed, 26 Mar 2008) | 4 lines

If we are requested to authenticate a reinvite make sure that it contains T38 SDP if need be.
(closes issue ASTERISK-11439)
Reported by: fall

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http://svn.digium.com/view/asterisk?view=rev&revision=111020
By: Digium Subversion (svnbot) 2008-03-26 14:01:22

Repository: asterisk
Revision: 111021

_U  trunk/
U   trunk/channels/chan_sip.c

------------------------------------------------------------------------
r111021 | file | 2008-03-26 14:01:21 -0500 (Wed, 26 Mar 2008) | 12 lines

Merged revisions 111020 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4

........
r111020 | file | 2008-03-26 16:04:35 -0300 (Wed, 26 Mar 2008) | 4 lines

If we are requested to authenticate a reinvite make sure that it contains T38 SDP if need be.
(closes issue ASTERISK-11439)
Reported by: fall

........

------------------------------------------------------------------------

http://svn.digium.com/view/asterisk?view=rev&revision=111021
By: Digium Subversion (svnbot) 2008-03-26 14:02:28

Repository: asterisk
Revision: 111023

_U  branches/1.6.0/
U   branches/1.6.0/channels/chan_sip.c

------------------------------------------------------------------------
r111023 | file | 2008-03-26 14:02:27 -0500 (Wed, 26 Mar 2008) | 20 lines

Merged revisions 111021 via svnmerge from
https://origsvn.digium.com/svn/asterisk/trunk

................
r111021 | file | 2008-03-26 16:05:42 -0300 (Wed, 26 Mar 2008) | 12 lines

Merged revisions 111020 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4

........
r111020 | file | 2008-03-26 16:04:35 -0300 (Wed, 26 Mar 2008) | 4 lines

If we are requested to authenticate a reinvite make sure that it contains T38 SDP if need be.
(closes issue ASTERISK-11439)
Reported by: fall

........

................

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http://svn.digium.com/view/asterisk?view=rev&revision=111023