[Asterisk-code-review] res_pjsip_nat: Restore original contact for REGISTER responses (...asterisk[13])

[George Joseph]

Hello Kevin Harwell, Friendly Automation, 

I'd like you to reexamine a change. Please visit

    https://gerrit.asterisk.org/c/asterisk/+/12824

to look at the new patch set (#3).

Change subject: res_pjsip_nat: Restore original contact for REGISTER responses
......................................................................

res_pjsip_nat: Restore original contact for REGISTER responses

RFC3261 Section 10 "Registrations", specifically paragraph
"10.2.4: Refreshing Bindings", states that a user agent compares
each contact address (in a 200 REGISTER response) to see if it
created the contact.  If the Asterisk endpoint has the
rewrite_contact option set however, the contact host and port sent
back in the 200 response will be the rewritten one and not the
one sent by the user agent.  This prevents the user agent from
matching its own contact.  Some user agents get very upset when
this happens and will not consider the registration successful.
While this is rare, it is acceptable behavior especially if more
than 1 user agent is allowed to register to a single endpoint/aor.

This commit updates res_pjsip_nat (where rewrite_contact is
implemented) to store the original incoming Contact header in
a new "x-ast-orig-host" URI parameter before rewriting it, and to
restore the original host and port to the Contact headers in the
outgoing response.

This is only done if the request is a REGISTER and rewrite_contact
is enabled.

pjsip_message_filter was also updated to ensure that if a request
comes in with any existing x-ast-* URI parameters, we remove them
so they don't conflict.  Asterisk will never send a request
with those headers in it but someone might just decide to add them
to a request they craft and send to Asterisk.

ASTERISK-28502
Reported-by: Ross Beer

Change-Id: Idc263ad2d2d7bd8faa047e5804d96a5fe1cd282e
---
M res/res_pjsip/pjsip_message_filter.c
M res/res_pjsip_nat.c
2 files changed, 102 insertions(+), 1 deletion(-)


  git pull ssh://gerrit.asterisk.org:29418/asterisk refs/changes/24/12824/3
-- 
To view, visit https://gerrit.asterisk.org/c/asterisk/+/12824
To unsubscribe, or for help writing mail filters, visit https://gerrit.asterisk.org/settings

Gerrit-Project: asterisk
Gerrit-Branch: 13
Gerrit-Change-Id: Idc263ad2d2d7bd8faa047e5804d96a5fe1cd282e
Gerrit-Change-Number: 12824
Gerrit-PatchSet: 3
Gerrit-Owner: George Joseph <gjoseph at digium.com>
Gerrit-Reviewer: Friendly Automation
Gerrit-Reviewer: George Joseph <gjoseph at digium.com>
Gerrit-Reviewer: Kevin Harwell <kharwell at digium.com>
Gerrit-CC: Alexei Gradinari <alex2grad at gmail.com>
Gerrit-MessageType: newpatchset
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.digium.com/pipermail/asterisk-code-review/attachments/20190910/6d71fab1/attachment.html>