[Kamailio-Devel] compare uri and aor

[Iñaki Baz Castillo]

2009/1/7 Daniel-Constantin Mierla <miconda at gmail.com>:
> Hello,
>
> I have introduced in siputils module functions to compare SIP URI and
> AoR in a more RFC manner, related to:
> https://sourceforge.net/tracker/index.php?func=detail&aid=2047019&group_id=139143&atid=743023

Great :)


> Now, for URI it does comparison of:
> - username
> - password
> - hostname
> - port

Are URI parameters taken into account?:

a)  sip:alice at domain
b)  sip:alice at domain;transport=tcp
They are different since a) could involve UDP transport while b) forces TCP.
A user, ttl, maddr, or method uri-parameter appearing in only one URI
never matches, even if it contains the default value.

a)  sip:alice at domain;custom_param=AAA
b)  sip:alice at domain;custom_param=BBB
The are different since they share a URI parameter with different value.

a)  sip:alice at domain;custom_param_1=AAA
b)  sip:alice at domain;custom_param_2=BBB
They match since custom parameters are just matched when they exist in
both URI's.




> For AoR, it does:
> - username
> - hostname
> - port (if port is missing, it assumes 5060 -- for URI comparison this
> is not used, conform to RFC3261)
>
> The questions are:

> - shall the comparison for URI be extended to follow full RFC? could get
> complex when taking URI headers in account -- haven't seen many, but the
> RFC allow them. Where to stop then the rules for comparing the URI?

Personally I would never implement exotic URI headers. This is
something that should be dropped from RFC 3261 ASAP.
Those super-exotic "features" are fully useless and add
extra-complexity. Why should a header be matched when comparing an
URI?


> - for AoR, I am not sure if port should be considered, but when running
> multiple instances on different ports, it may make the difference? What
> do you think?

Complex question. Probably port must be taken into account since, as
you say, the same server (same domain) could have two servers in
different ports, so "sip:alice at domain" differs from
"sip:alice at domain:5070". But also, it breaks RFC 3263.

For example, if a server listens in "domain:5070" and there are no SRV
registers for "_sip._udp.domain" pointing to port 5070, then it
requires the user configure an account with this data:

  user: alice
  domain:  domain:5070  <-- annoying

So the From would be:
  From: <sip:alice at domain:5070>

If the user configures his device with "domain = domain" (no port) and
uses an outbound proxy (domain:5070) then his From would point to a
different server (a MESSAGE conversation would fail when a reply
MESSAGE goes to "sip:alice at domain").

Unfortunatelly I've already seen some implementations adding the
default port 5060 to the From domain even if no port is set in the
configuration (just the domain). So in conclussion I think your
approach is correct (or the least wrong xD).


-- 
Iñaki Baz Castillo
<ibc at aliax.net>