#!KAMAILIO
####### Include Local Config If Exists #########
import_file "kamailio-local.cfg"

debug=2
log_stderror=no

memdbg=5
memlog=5

log_facility=LOG_LOCAL0

fork=yes
children=4

/* uncomment the next line to disable TCP (default on) */
disable_tcp=yes

/* uncomment the next line to disable the auto discovery of local aliases
   based on reverse DNS on IPs (default on) */
auto_aliases=no

/* port to listen to
 * - can be specified more than once if needed to listen on many ports */
port=5060

mpath="/usr/local/lib/kamailio/modules_k/:/usr/lib64/kamailio/modules/"

loadmodule "mi_fifo.so"
loadmodule "kex.so"
loadmodule "corex.so"
loadmodule "tm.so"
loadmodule "tmx.so"
loadmodule "sl.so"
loadmodule "rr.so"
loadmodule "pv.so"
loadmodule "maxfwd.so"
loadmodule "usrloc.so"
loadmodule "registrar.so"
loadmodule "textops.so"
loadmodule "siputils.so"
loadmodule "xlog.so"
loadmodule "sanity.so"
loadmodule "ctl.so"
loadmodule "cfg_rpc.so"
loadmodule "mi_rpc.so"
loadmodule "acc.so"

loadmodule "path.so"

loadmodule "htable.so"
loadmodule "pike.so"

loadmodule "nat_traversal.so"
loadmodule "nathelper.so"

# ----------------- setting module-specific parameters ---------------


# ----- mi_fifo params -----
modparam("mi_fifo", "fifo_name", "/tmp/kamailio_fifo")


# ----- tm params -----
# auto-discard branches from previous serial forking leg
modparam("tm", "failure_reply_mode", 3)
# default retransmission timeout: 30sec
modparam("tm", "fr_timer", 30000)
# default invite retransmission timeout after 1xx: 120sec
modparam("tm", "fr_inv_timer", 120000)


# ----- rr params -----
# add value to ;lr param to cope with most of the UAs
modparam("rr", "enable_full_lr", 1)
# do not append from tag to the RR (no need for this script)
modparam("rr", "append_fromtag", 0)

modparam("nat_traversal", "keepalive_interval", 2 )
modparam("nat_traversal", "keepalive_method", "OPTIONS")
modparam("nat_traversal", "keepalive_from", "sip:keepalive@nat.mydomain.net")
modparam("nat_traversal", "keepalive_state_file", "/var/run/kamailio/keepalive_state") 


####### Routing Logic ########

# Main SIP request routing logic
# - processing of any incoming SIP request starts with this route
# - note: this is the same as route { ... }
request_route {

	# per request initial checks
	route(REQINIT);

	if ( is_method("OPTIONS"))
	{
		options_reply();
		exit ;
	}
	# Respond quickly to keep alive
	if ( is_method("NOTIFY") && $hdr(Event) == 'keep-alive' )
	{
		xlog("L_DEBUG", "Notify : Keep alive $fU\n"); 
		sl_send_reply('200', 'OK');
		exit;
	}



	# NAT detection
	route(NAT);

	if (is_method("REGISTER"))
	{
		if (!add_path()) {
			sl_send_reply("503", "Internal Path Error");
			exit;
		}
	}
	else
	{

		# handle requests within SIP dialogs
		route(WITHINDLG);

		record_route();
	}

	route(RELAY);
}

route[RELAY] {
        if (is_method("INVITE")) {
                t_on_reply("REPLY_ONE");
        }

	if ( !t_relay() )
		sl_reply_error(); 
	exit;
}

route[NAT] {

          if (client_nat_test("5")) {
               force_rport();
               append_hf("X-NAT-URI: $source_uri\r\n");
               if (method=="REGISTER") {
                    # alias in contact to work around fix_contact which breaks nat_keepalive() and rport which doesn't do anything useful
		    fix_contact();

                    xlog("L_INFO", "Requesting NAT keep alive - M=$rm RURI=$ru F=$fu T=$tu IP=$si DT=$tt FT=$ft ID=$ci\n") ;
                    nat_keepalive();
                    xlog("L_INFO", "Done requesting NAT keep alive - M=$rm RURI=$ru F=$fu T=$tu IP=$si DT=$tt FT=$ft ID=$ci\n") ;

                    #add_contact_alias();
               }
               else
               {
                    fix_contact();
               }
               if ( nat_uac_test("8") )
               {
                    fix_nated_sdp("2");
               }

     }
}
# Handle requests within SIP dialogs
route[WITHINDLG] {

     # sequential request withing a dialog should
     # take the path determined by record-routing
     if ( has_totag() )
     {
	     if (loose_route()) {
		     xlog("L_INFO", "Loose routing!- M=$rm RURI=$ru F=$fu T=$tu IP=$si DT=$tt FT=$ft ID=$ci\n");
		     route(RELAY);
	     } else {
		     if ( has_totag() && is_method("ACK") && t_check_trans() ) {
			# no loose-route, but stateful ACK;
			# must be an ACK after a 487
			# or e.g. 404 from upstream server
			     t_relay();
			     exit;
		     }
	     }
     }
}



# Caller NAT detection route
route[NAT_REPLY] {


          if (client_nat_test("5")) {
               force_rport();
               append_hf("X-NAT-URI: $source_uri\r\n");
               if (method=="REGISTER") {
                    xlog("L_INFO", "Requesting NAT keep alive - M=$rm RURI=$ru F=$fu T=$tu IP=$si DT=$tt FT=$ft ID=$ci\n") ;
                    nat_keepalive();
                    # alias in contact to work around fix_contact which breaks nat_keepalive() and rport which doesn't do anything useful
                    add_contact_alias();
               }
               else
               {
                    fix_contact();
               }
               if ( nat_uac_test("8") )
               {
                    fix_nated_sdp("2");
               }

     }
}




route[REQINIT] {
       # flood dection from same IP and traffic ban for a while
       # be sure you exclude checking trusted peers, such as pstn gateways
       # - local host excluded (e.g., loop to self)
       if(src_ip!=myself)
       {
               if($sht(ipban=>$si)!=$null)
               {
                       # ip is already blocked
                       xdbg("request from blocked IP - $rm from $fu (IP:$si:$sp)\n");
                        exit;
                }
               if (!pike_check_req())
               {
                       xlog("L_ALERT","ALERT: pike blocking $rm from $fu (IP:$si:$sp)\n");
                       $sht(ipban=>$si) = 1;
                       exit;
               }
        }

       if (!mf_process_maxfwd_header("10")) {
               sl_send_reply("483","Too Many Hops");
               exit;
       }

       if(!sanity_check("1511", "7"))
       {
               xlog("Malformed SIP message from $si:$sp\n");
               exit;
       }
}

# Sample onreply route
onreply_route[REPLY_ONE] {
        xdbg("incoming reply\n");

route(NAT_REPLY);

}