Forum Discussion

Joss_100621's avatar
Joss_100621
Icon for Nimbostratus rankNimbostratus
Jan 04, 2010

SIP TLS transformation

Hi,

 

 

We are using bigip to terminate SIP/TLS sessions and forward it over TCP to a SIP server.

 

We need to replace the sips: uri coming from the client to sip: towards the server otherwise the server rejects the request.

 

of course the opposite transformation (from sip to sips) has to be made on traffic from server to client.

 

 

Here is a sample message from client:

 

 

REGISTER sips:xxx.xxx:5061;transport=TCP SIP/2.0

 

From: ;tag=b660828-b1040a0a-13c5-55016-57053-645b33cc-57053

 

To:

 

Call-ID: b67dee8-b1040a0a-13c5-55016-57053-378dbf4e-57053

 

CSeq: 1 REGISTER

 

Via: SIP/2.0/TLS w.x.y.z:5061;rport;branch=z9hG4bK-57053-153ec597-148752e

 

Max-Forwards: 70

 

Supported: replaces,100rel,timer,eventlist

 

User-Agent: xxx

 

Require: pref

 

Expires: 3600

 

Contact: ;

 

Content-Length: 0

 

 

Do you have any idea on how to achieve this?

 

 

Thanks.
application delivery
dev
devops
iRules
  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Jan 04, 2010
    Hi,

     

     

    Can you try the SIP::header commands (Click here) to save, remove and insert a new version of the headers? You could use string map to replace sips: with sip:.

     

     

    set sip_from [string map -nocase {sips: sip:} [SIP::header From]]

     

    SIP::header remove From

     

    SIP::header insert From $sip_from

     

     

    Aaron
  • Joss_100621's avatar
    Joss_100621
    Icon for Nimbostratus rankNimbostratus
    Jan 04, 2010
    Thanks for that.

     

     

    Do you know how to change to change the request uri line: REGISTER sips:xxx.xxx:5061;transport=TCP SIP/2.0 ?
  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Jan 04, 2010
    SIP::uri can be used to retrieve/modify the URI.

     

     

    Aaron
  • Joss_100621's avatar
    Joss_100621
    Icon for Nimbostratus rankNimbostratus
    Jan 04, 2010
    Per the documentation this is only to retrieve the request uri and not to set it.

     

    if I try something like:

     

    set sip_uri [string map -nocase {sips: sip:} [SIP::uri]]

     

    SIP::uri remove

     

    SIP::uri insert To $sip_uri

     

     

    It fails to parse.
  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Jan 04, 2010
    Sorry, from this post (Click here) I thought the functionality might have been changed. I'm not sure whether/how you can modify the SIP URI if not with SIP::uri. You could open a case with F5 Support and ask. There are a few people who have asked:

     

     

    Replace IP address in SIP Notify in iRule

     

    http://devcentral.f5.com/Default.aspx?tabid=53&forumid=5&tpage=1&view=topic&postid=86218

     

     

    SIP content modification

     

    http://devcentral.f5.com/Default.aspx?tabid=53&forumid=5&tpage=1&view=topic&postid=1880118802

     

     

    How to modify SIP::uri

     

    http://devcentral.f5.com/Default.aspx?tabid=53&view=topic&postid=33065&ptarget=33065

     

     

    If you find any more info on this, can you reply here for future reference?

     

     

    Thanks,

     

    Aaron
  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Jan 06, 2010
    Hi Michael,

     

     

    Thanks for the tip. Was this change made in 9.4.8 and 10.0.0? I tried searching on AskF5 but didn't find anything related. The wiki still shows SIP::uri can only retrieve the value.

     

     

    Thanks,

     

    Aaron
  • Michael_Voight_'s avatar
    Michael_Voight_
    Historic F5 Account
    Jan 07, 2010
    I don't know. IT was the response in a subcase sent to Dev.

     

    It is not documented.
  • Joss_100621's avatar
    Joss_100621
    Icon for Nimbostratus rankNimbostratus
    Jan 07, 2010
    Hi All,

    Its confirmed to be working on 9.4.8

    It looks like a documentation bug.

    I have used the following to transform the sips URI to sip: 

     
 set sip_uri [string map -nocase {sips: sip:} [SIP::uri]] 
 SIP::uri $sip_uri

    Thanks a lot for your tips, it was absolutely invaluable.
  • Michael_Voight_'s avatar
    Michael_Voight_
    Historic F5 Account
    Jan 08, 2010
    I received this answer in my subcase.

     

     

    This ability was added to SIP::uri in 9.4.0, so it should be there in all

     

    9.4.x and 10.x.x versions.