From 8aa9fac0e338e76643fcf856b709914d0f1dc525 Mon Sep 17 00:00:00 2001
From: lazedo <luis.azedo@factorlusitano.com>
Date: Mon, 9 Sep 2019 05:43:50 +0000
Subject: [PATCH] allow header removal when sending to AOR

we want to send some headers (default is P-* and R-*)
to carriers but not to devices
---
 kamailio/default.cfg | 39 +++++++++++++++++++++++++++++++++++++--
 1 file changed, 37 insertions(+), 2 deletions(-)

diff --git a/kamailio/default.cfg b/kamailio/default.cfg
index edb4aa7..20d44d2 100644
--- a/kamailio/default.cfg
+++ b/kamailio/default.cfg
@@ -151,6 +151,9 @@ modparam("rr", "enable_full_lr", RR_FULL_LR)
 modparam("rr", "enable_double_rr", RR_DOUBLE_RR)
 modparam("rr", "force_send_socket", RR_FORCE_SOCKET)
 
+######## Kamailio dialog module ########
+loadmodule "dialog.so"
+
 ######## Max-Forward processor module ########
 loadmodule "maxfwd.so"
 modparam("maxfwd", "max_limit", 50)
@@ -593,6 +596,11 @@ route[PREPARE_INITIAL_REQUESTS]
         exit();
     }
 
+    if(is_method("INVITE"))
+    {
+        dlg_manage();
+    }
+
     if (is_method("UPDATE")) {
         xlog("L_WARN", "$ci|end|update outside dialog not allowed\n");
         send_reply("403", "Dialog does not exist");
@@ -685,6 +693,12 @@ route[INTERNAL_TO_EXTERNAL_RELAY]
     }
     #!endif
 
+    if (dlg_isflagset(FLT_AOR)) {
+        if($sel(cfg_get.kazoo.aor_strip_headers) == 1) {
+            xlog("L_INFO", "$ci|log|INTERNAL TO EXTERNAL AOR REMOVE HDR\n");
+            remove_hf_re($sel(cfg_get.kazoo.aor_strip_headers_regex));
+        }
+    }
 
     t_on_reply("EXTERNAL_REPLY");
 
@@ -770,6 +784,13 @@ onreply_route[INTERNAL_REPLY]
         setflag(FLAG_SESSION_PROGRESS);
     }
 
+    if (dlg_isflagset(FLT_AOR)) {
+        if($sel(cfg_get.kazoo.aor_strip_headers) == 1) {
+            xlog("L_INFO", "$ci|log|INTERNAL TO EXTERNAL REPLY AOR REMOVE HDR\n");
+            remove_hf_re($sel(cfg_get.kazoo.aor_strip_headers_regex));
+        }
+    }
+
     if ($rs < 300) {
         xlog("L_INFO", "$ci|pass|$T_req($si):$T_req($sp)\n");
     }
@@ -880,6 +901,16 @@ onsend_route {
     }
 }
 
+
+#!trydef STRIP_HEADERS_TO_AOR 1
+#!trydef STRIP_HEADERS_TO_AOR_REGEX "^P-.*|^R-.*"
+
+kazoo.aor_strip_headers = STRIP_HEADERS_TO_AOR desc "should we remove headers when sending to AOR"
+kazoo.aor_strip_headers_regex = STRIP_HEADERS_TO_AOR_REGEX desc "regex used to remove headers before sending to AOR"
+
+#!trydef AOR_NOT_SUBSCRIBED_APPEND_REASON
+#!trydef AOR_NOT_SUBSCRIBED_REASON Reason: Q.850; cause=20;text="Subscriber Absent"
+
 route[ROUTE_TO_AOR]
 {
     if ($hdr(X-KAZOO-AOR) == $null) {
@@ -887,22 +918,26 @@ route[ROUTE_TO_AOR]
     }
 
     xlog("L_INFO", "$ci|log|using AOR $hdr(X-KAZOO-AOR)\n");
+    dlg_setflag(FLT_AOR);
     if ($hdr(X-KAZOO-INVITE-FORMAT) == "contact") {
        if(lookup("location", "$hdr(X-KAZOO-AOR)") > 0){
           xlog("L_INFO", "$ci|end|routing to contact $ru\n");
+          $avp(aor) = $hdr(X-KAZOO-AOR);
           handle_ruri_alias();
        } else {
           xlog("L_INFO", "$ci|end|lookup for AOR $hdr(X-KAZOO-AOR) failed\n");
-          sl_send_reply("410", "Not registered");
+          append_to_reply("$def(AOR_NOT_SUBSCRIBED_REASON)\r\n");
+          sl_send_reply("480", "Not registered");
           exit;
        }
     } else if (reg_fetch_contacts("location", "$hdr(X-KAZOO-AOR)", "callee")) {
        $du = $(ulc(callee=>received));
        $fs = $(ulc(callee=>socket));
        xlog("L_INFO", "$ci|log|routing $hdr(X-KAZOO-AOR) to $du via $fs\n");
-       
+       $avp(aor) = $hdr(X-KAZOO-AOR);
     } else {
        xlog("L_INFO", "$ci|end|user is not registered\n");
+       append_to_reply("$def(AOR_NOT_SUBSCRIBED_REASON)\r\n");
        sl_send_reply("410", "Not registered");
        exit;
     }