[Devel] Re: uac_auth - set credentials with avpops

[Thomas Gelf]

Sorry for posting my last message twice - here some additional
thoughts:

I must confess that I never wrote anything with C - but nonetheless
I tried to understand what's going on in the uac module and got some
idea of how things work.

What do you think about extending uac_auth() to allow it to accept
one (optional) parameter - like uac_auth("user:pass:realm")? Parsing
avpops has already been added to uac_replace_from() and I believe that
it would be a trivial job (for someone experienced with C and knowing
OpenSER's internals) to do so also for uac_auth().

Adding such an (optional - of course) parameter would be 100% backward-
compatible and allow you to rewrite credentials however you would like
to do so.

If there is no good reason why this shouldn't be done this way I would
be really happy if someone could give me a hint on how to create such
a patch. I promise you that I'll do extensive testing :-)

Below I tried to "code" what I would uac_auth() like to do for me. As
told before I have absolutely no C knowledge so the way how I passed
variables to functions or compared values (like cdr == 0) could be a
great nonsense - please forgive me.

Be patient with me, don't take my coding too serious - just think about
what I'm trying to do and maybe give me some little help ;-)

Cheers & thanks a lot for your help,
Thomas Gelf

uac.c
=====

   static cmd_export_t cmds[]={
..
-    {"uac_auth",          w_uac_auth,       0,                  0,
-                    FAILURE_ROUTE },
+    {"uac_auth",          w_uac_auth,       1,    fixup_uac_auth1,
+                    FAILURE_ROUTE },
..

   /***************** fixup functions ******************************/

+ static int fixup_uac_auth1(void** param, int param_no)
+ {
+   xl_elem_t *model;
+
+   model=NULL;
+   if(xl_parse_format((char*)(*param),&model,XL_DISABLE_COLORS)<0)
+   {
+     LOG(L_ERR, "ERROR:uac:fixup_uac_auth1: wrong format[%s]!\n",
+             (char*)(*param));
+     return E_UNSPEC;
+   }
+   if (model==NULL)
+   {
+     LOG(L_ERR, "ERROR:uac:fixup_replace_from1: empty parameter!\n");
+     return E_UNSPEC;
+   }
+   *param = (void*)model;
+
+   return 0;
+ }

   /**************** wrapper functions ******************************/

   static int w_uac_auth(struct sip_msg* msg, char* str, char* str2)
   {
-   return (uac_auth(msg)==0)?1:-1;
+   return (uac_auth(msg, &str)==0)?1:-1;
   }


auth.c
======

- int uac_auth( struct sip_msg *msg)
+ int uac_auth( struct sip_msg *msg, struct uac_credential *crd)
   {
     static struct authenticate_body auth;
-   struct uac_credential *crd;

...
   /* can we authenticate this realm? */
- crd = lookup_realm( &auth.realm );
+ if (crd == 0)
+ {
+   crd = lookup_realm( &auth.realm );
+ }