[asterisk-bugs] [JIRA] (ASTERISK-27082) Fax error when receive a CSI has a wrong character encoding

[Sean Bright (JIRA)]

    [ https://issues.asterisk.org/jira/browse/ASTERISK-27082?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=237561#comment-237561 ] 

Sean Bright commented on ASTERISK-27082:
----------------------------------------

Quoting from Recommendation T.30:

{quote}
The facsimile information field of the CSI signal shall be the international telephone number
including the "+" character, the telephone country code, area code and subscriber number. This field
shall consist of 20 numeric digits coded as shown in Table 3 but excluding the "*" and "#"
characters. The least significant bit of the least significant digit shall be the first bit transmitted.
{quote}

This looks like an error on the sender's side

> Fax error when receive a CSI has a wrong character encoding
> -----------------------------------------------------------
>
>                 Key: ASTERISK-27082
>                 URL: https://issues.asterisk.org/jira/browse/ASTERISK-27082
>             Project: Asterisk
>          Issue Type: Bug
>      Security Level: None
>          Components: Resources/res_fax_spandsp
>    Affects Versions: 13.16.0
>         Environment: Debian 8
>            Reporter: Ludovic Gasc (Eyepea)
>            Assignee: Unassigned
>            Severity: Minor
>
> Hi,
> When we use SendFAX application, we have found a fax machine that stops prematurely Fax session.
> It seems a character encoding issue:
> The logs:
> {noformat}
> [Jun 22 09:52:07] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.38 Rx    82: (0) data v21/hdlc-fcs-OK-sig-end + 0 byte(s)
> [Jun 22 09:52:07] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.38T Type CSI - CRC OK, sig end (clean)
> [Jun 22 09:52:07] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.30 Stop T4 (13840 remaining)
> [Jun 22 09:52:07] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.30 Rx:  CSI without final frame tag
> [Jun 22 09:52:07] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.30 Rx:  ff 03 40 36 32 ff 13 84
> [Jun 22 09:52:07] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.30 Remote gave CSI as: "��26" 
> [Jun 22 09:52:07] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.30 HDLC signal status is Carrier down (-1) in state 6
> [Jun 22 09:52:07] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.30 HDLC signal status is Carrier down (-1) in state 6
> [Jun 22 09:52:07] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.30 No signal is present
> [Jun 22 09:52:07] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.38 Rx    83: IFP 00
> [Jun 22 09:52:07] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.38 Rx    83: indicator no-signal
> [Jun 22 09:52:33] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.30 Status changing to 'The call dropped prematurely'
> [Jun 22 09:52:33] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.30 Changing from state 6 to 30
> [Jun 22 09:52:33] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.30 Changing from phase T30_PHASE_B_RX to T30_PHASE_CALL_FINISHED
> [Jun 22 09:52:33] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.38T Set rx type 9
> [Jun 22 09:52:33] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.38T Set tx type 9
> [Jun 22 09:52:33] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.38T FAX exchange complete
> [Jun 22 09:52:33] FAX[24642][C-00000007]: res_fax.c:1039 ast_fax_log: FLOW T.30 Call completed
> [Jun 22 09:52:33] ERROR[24642][C-00000007]: json.c:825 ast_json_vpack: Error building JSON from '{s: s, s: s}': Invalid UTF-8 string.
> [Jun 22 09:52:33] ERROR[24642][C-00000007]: stasis_channels.c:771 ast_channel_publish_varset: Error creating message
> [Jun 22 09:52:33] ERROR[24642][C-00000007]: json.c:825 ast_json_vpack: Error building JSON from '{s: s, s: s, s: s, s: s, s: s, s: s, s: o}': Invalid UTF-8 string.
> [Jun 22 09:52:33] ERROR[24642][C-00000007]: res_fax.c:2808 sendfax_exec: Error publishing SendFAX status message
> {noformat}
> We have the PCAP, but we can't share publicly on the Internet.
> The strange thing, is that we don't seem to have this issue with another server with Asterisk 13.15. But, for an unknown reason, it doesn't use T.38 for the same number: 
> {noformat}
> [Jun 22 12:40:56] FAX[7619][C-00000037]: res_fax.c:1039 ast_fax_log: FLOW T.30 The remote was made in 'Japan'
> [Jun 22 12:40:56] FAX[7619][C-00000037]: res_fax.c:1039 ast_fax_log: FLOW T.30 The remote was made by 'Brother'
> [Jun 22 12:40:56] FAX[7619][C-00000037]: res_fax.c:1039 ast_fax_log: FLOW T.30 Stop none (0 remaining)
> [Jun 22 12:40:56] FAX[7619][C-00000037]: res_fax.c:1039 ast_fax_log: FLOW T.30 Rx:  CSI without final frame tag
> [Jun 22 12:40:56] FAX[7619][C-00000037]: res_fax.c:1039 ast_fax_log: FLOW T.30 Rx:  ff 03 40 36 32 30 39 35 35 33 32 32 33 2b 20 20 20 20 20 20 20 20 20
> [Jun 22 12:40:56] FAX[7619][C-00000037]: res_fax.c:1039 ast_fax_log: FLOW T.30 Remote gave CSI as: "+3223559026" 
> {noformat}



--
This message was sent by Atlassian JIRA
(v6.2#6252)