[asterisk-bugs] [Asterisk 0015586]: [patch] Failure to negotiate T.38

Thu Sep 17 09:21:38 CDT 2009

A NOTE has been added to this issue. 
====================================================================== 
https://issues.asterisk.org/view.php?id=15586 
====================================================================== 
Reported By:                globalnetinc
Assigned To:                kpfleming
====================================================================== 
Project:                    Asterisk
Issue ID:                   15586
Category:                   Channels/chan_sip/T.38
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     assigned
Asterisk Version:           SVN 
Regression:                 No 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
====================================================================== 
Date Submitted:             2009-07-26 15:57 CDT
Last Modified:              2009-09-17 09:21 CDT
====================================================================== 
Summary:                    [patch] Failure to negotiate T.38
Description: 
To implement T.38 on most ATAs their is a reinvite required.  In the
process of gatewaying the T.38 negotiations the Asterisk server is not
doing this correctly.  On versions past 1.6.0.10 it does not even send the
same ports on the RTP streams to both parties.  

Every version past 1.6.0.10 fails
1.6.0.11
1.6.1.0
1.6.1.1
1.6.2.0-rc

This also includes the new T.38 stack that is is being introduced. in the
SVN tree of 1.6.1.1 and 1.6.2.0
======================================================================
Relationships       ID      Summary
----------------------------------------------------------------------
has duplicate       0015886 T38 udptl.c bufferoverflow
====================================================================== 

---------------------------------------------------------------------- 
 (0110864) vrban (reporter) - 2009-09-17 09:21
 https://issues.asterisk.org/view.php?id=15586#c110864 
---------------------------------------------------------------------- 
With issue-15586.patch and analog fax (brother FAX-2820) is set to it's
safe speed 9600, i get

[Sep 17 16:06:34] WARNING[10255]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:06:34] WARNING[10255]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:06:34] WARNING[10255]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:06:34] WARNING[10255]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:06:34] WARNING[10255]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:06:34] WARNING[10255]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
    -- Executing [s at t38-faxout:4] NoOp("SIP/10-088f34e8", "###      
FAXSTATUS: SUCCESS") in new stack
    -- Executing [s at t38-faxout:5] NoOp("SIP/10-088f34e8", "###       
FAXERROR: ") in new stack
    -- Executing [s at t38-faxout:6] NoOp("SIP/10-088f34e8", "###        
FAXMODE: T38") in new stack
    -- Executing [s at t38-faxout:7] NoOp("SIP/10-088f34e8", "###       
FAXPAGES: 1") in new stack
    -- Executing [s at t38-faxout:8] NoOp("SIP/10-088f34e8", "###     
FAXBITRATE: 9600") in new stack
    -- Executing [s at t38-faxout:9] NoOp("SIP/10-088f34e8", "###  
FAXRESOLUTION: 3850") in new stack

With issue-15586.patch and analog fax (brother FAX-2820) is set to it's
max speed 14400, i get

...
[Sep 17 16:12:56] ERROR[10379]: udptl.c:299 encode_open_type: Buffer
overflow detected (50 + 158 > 200)
[Sep 17 16:12:56] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 50 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:12:56] ERROR[10379]: udptl.c:299 encode_open_type: Buffer
overflow detected (50 + 158 > 200)
[Sep 17 16:12:56] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 50 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:12:56] ERROR[10379]: udptl.c:299 encode_open_type: Buffer
overflow detected (50 + 158 > 200)
[Sep 17 16:12:56] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 50 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:12:56] ERROR[10379]: udptl.c:299 encode_open_type: Buffer
overflow detected (50 + 158 > 200)
[Sep 17 16:12:56] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 50 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:12:56] ERROR[10379]: udptl.c:299 encode_open_type: Buffer
overflow detected (50 + 158 > 200)
[Sep 17 16:12:56] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 50 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:12:56] ERROR[10379]: udptl.c:299 encode_open_type: Buffer
overflow detected (50 + 158 > 200)
[Sep 17 16:12:56] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 50 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:12:56] ERROR[10379]: udptl.c:299 encode_open_type: Buffer
overflow detected (50 + 158 > 200)
[Sep 17 16:12:56] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 50 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:12:56] ERROR[10379]: udptl.c:299 encode_open_type: Buffer
overflow detected (50 + 158 > 200)
[Sep 17 16:13:02] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
    -- Remote UNIX connection disconnected
[Sep 17 16:13:02] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:13:02] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:13:02] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:13:02] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:13:02] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:13:02] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:13:02] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:13:02] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
[Sep 17 16:13:02] WARNING[10379]: udptl.c:1021 ast_udptl_write: UDPTL
asked to send 41 bytes of IFP when far end only prepared to accept 36
bytes; data loss may occur.
...
    -- Executing [s at t38-faxout:4] NoOp("SIP/10-088f34e8", "###      
FAXSTATUS: SUCCESS") in new stack
    -- Executing [s at t38-faxout:5] NoOp("SIP/10-088f34e8", "###       
FAXERROR: ") in new stack
    -- Executing [s at t38-faxout:6] NoOp("SIP/10-088f34e8", "###        
FAXMODE: T38") in new stack
    -- Executing [s at t38-faxout:7] NoOp("SIP/10-088f34e8", "###       
FAXPAGES: 1") in new stack
    -- Executing [s at t38-faxout:8] NoOp("SIP/10-088f34e8", "###     
FAXBITRATE: 9600") in new stack
    -- Executing [s at t38-faxout:9] NoOp("SIP/10-088f34e8", "###  
FAXRESOLUTION: 3850") in new stack

In all four settings the fax transmissions is a success, even with this
ERROR/WARNING messages 

Issue History 
Date Modified    Username       Field                    Change               
====================================================================== 
2009-09-17 09:21 vrban          Note Added: 0110864                          
======================================================================