Hello!
Today at SIPit 29 we successfully tested the kamailio auth_identity module that implements
RFC 4474.
We could successfully add SIP identity headers and verify incoming headers from one other
implementation.
Now, the module is not built for scalability and redundance. A lot of stuff is cached in
RAM, like certificates - which could lead to an DOS attack vector. It doesn't make it
simple either when you have multiple servers for one domain. Maybe a memcached backend
could help.
We will also try to look for other attack vectors, like sending bad HTTPS URL's.
Regardless, this was the first time I got SIP identity working and the others are
struggling with their code to get their end working :-)
Kamailio rocks.
/O