res_pjsip_nat.c File Reference

#include "asterisk.h"
#include <pjsip.h>
#include <pjsip_ua.h>
#include "asterisk/res_pjsip.h"
#include "asterisk/res_pjsip_session.h"
#include "asterisk/module.h"
#include "asterisk/acl.h"

Include dependency graph for res_pjsip_nat.c:

Go to the source code of this file.

Data Structures
struct	nat_hook_details
	Structure which contains hook details. More...
struct	request_transport_details
	Structure which contains information about a transport. More...

Macros
#define	AST_SIP_X_AST_ORIG_HOST   "x-ast-orig-host"
#define	AST_SIP_X_AST_ORIG_HOST_LEN   15
#define	COLON_LEN   1
#define	is_sip_uri(uri)   (PJSIP_URI_SCHEME_IS_SIP(uri) || PJSIP_URI_SCHEME_IS_SIPS(uri))
#define	MAX_PORT_LEN   5

Functions
static void	__reg_module (void)
static void	__unreg_module (void)
struct ast_module *	AST_MODULE_SELF_SYM (void)
static int	find_transport_state_in_use (void *obj, void *arg, int flags)
	Callback function for finding the transport the request is going out on. More...
static pj_bool_t	handle_rx_message (struct ast_sip_endpoint *endpoint, pjsip_rx_data *rdata)
static int	load_module (void)
static pjsip_sip_uri *	nat_get_contact_sip_uri (pjsip_tx_data *tdata)
	Helper function which returns the SIP URI of a Contact header. More...
static int	nat_incoming_invite_request (struct ast_sip_session *session, struct pjsip_rx_data *rdata)
	Function called when an INVITE goes out. More...
static void	nat_incoming_invite_response (struct ast_sip_session *session, struct pjsip_rx_data *rdata)
	Function called when an INVITE response comes in. More...
static int	nat_invoke_hook (void *obj, void *arg, int flags)
	Callback function for invoking hooks. More...
static pj_bool_t	nat_on_rx_message (pjsip_rx_data *rdata)
static pj_status_t	nat_on_tx_message (pjsip_tx_data *tdata)
static void	nat_outgoing_invite_request (struct ast_sip_session *session, struct pjsip_tx_data *tdata)
	Function called when an INVITE comes in. More...
static pj_status_t	process_nat (pjsip_tx_data *tdata)
static void	restore_orig_contact_host (pjsip_tx_data *tdata)
static int	rewrite_contact (pjsip_rx_data *rdata, pjsip_dialog *dlg)
static int	rewrite_route_set (pjsip_rx_data *rdata, pjsip_dialog *dlg)
static void	rewrite_uri (pjsip_rx_data *rdata, pjsip_sip_uri *uri, pj_pool_t *pool)
static void	save_orig_contact_host (pjsip_rx_data *rdata, pjsip_sip_uri *uri)
static int	unload_module (void)

Variables
static struct ast_module_info	__mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "PJSIP NAT Support" , .key = "This paragraph is copyright (c) 2006 by Digium, Inc. \In order for your module to load, it must return this \key via a function called \"key\". Any code which \includes this paragraph must be licensed under the GNU \General Public License version 2 or later (at your \option). In addition to Digium's general reservations \of rights, Digium expressly reserves the right to \allow other parties to license this paragraph under \different terms. Any use of Digium, Inc. trademarks or \logos (including \"Asterisk\" or \"Digium\") without \express written permission of Digium, Inc. is prohibited.\n" , .buildopt_sum = "30ef0c93b36035ec78c9cfd712d36d9b" , .support_level = AST_MODULE_SUPPORT_CORE, .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_APP_DEPEND, .requires = "res_pjsip,res_pjsip_session", }
static const struct ast_module_info *	ast_module_info = &__mod_info
static pjsip_module	nat_module
static struct ast_sip_session_supplement	nat_supplement
	Supplement for adding NAT functionality to dialog. More...

Macro Definition Documentation

AST_SIP_X_AST_ORIG_HOST

#define AST_SIP_X_AST_ORIG_HOST   "x-ast-orig-host"

URI parameter for original host/port

Definition at line 37 of file res_pjsip_nat.c.

Referenced by restore_orig_contact_host(), and save_orig_contact_host().

AST_SIP_X_AST_ORIG_HOST_LEN

#define AST_SIP_X_AST_ORIG_HOST_LEN   15

Definition at line 38 of file res_pjsip_nat.c.

Referenced by restore_orig_contact_host().

COLON_LEN

#define COLON_LEN   1

Referenced by save_orig_contact_host().

is_sip_uri

#define is_sip_uri

(

uri

)

(PJSIP_URI_SCHEME_IS_SIP(uri) || PJSIP_URI_SCHEME_IS_SIPS(uri))

Definition at line 40 of file res_pjsip_nat.c.

Referenced by restore_orig_contact_host().

MAX_PORT_LEN

#define MAX_PORT_LEN   5

Referenced by save_orig_contact_host().

Function Documentation

__reg_module()

static void __reg_module ( void  )

static

Definition at line 556 of file res_pjsip_nat.c.

__unreg_module()

static void __unreg_module ( void  )

static

Definition at line 556 of file res_pjsip_nat.c.

AST_MODULE_SELF_SYM()

struct ast_module* AST_MODULE_SELF_SYM

(

void

)

Definition at line 556 of file res_pjsip_nat.c.

find_transport_state_in_use()

static int find_transport_state_in_use ( void *  obj, void *  arg, int  flags  )

static

Callback function for finding the transport the request is going out on.

Definition at line 254 of file res_pjsip_nat.c.

References CMP_MATCH, ast_sip_transport_state::factory, request_transport_details::factory, request_transport_details::local_address, request_transport_details::local_port, ast_sip_transport_state::transport, request_transport_details::transport, ast_sip_transport_state::type, and request_transport_details::type.

Referenced by process_nat().

{
   struct ast_sip_transport_state *transport_state = obj;
   struct request_transport_details *details = arg;

   /* If an explicit transport or factory matches then this is what is in use, if we are unavailable
    * to compare based on that we make sure that the type is the same and the source IP address/port are the same
    */
   if (transport_state && ((details->transport && details->transport == transport_state->transport) ||
      (details->factory && details->factory == transport_state->factory) ||
      ((details->type == transport_state->type) && (transport_state->factory) &&
         !pj_strcmp(&transport_state->factory->addr_name.host, &details->local_address) &&
         transport_state->factory->addr_name.port == details->local_port))) {
      return CMP_MATCH;
   }

   return 0;
}

handle_rx_message()

static pj_bool_t handle_rx_message ( struct ast_sip_endpoint *  endpoint, pjsip_rx_data *  rdata  )

static

Definition at line 200 of file res_pjsip_nat.c.

References ast_sip_endpoint_nat_configuration::force_rport, ast_sip_endpoint::nat, rewrite_contact(), ast_sip_endpoint_nat_configuration::rewrite_contact, and rewrite_route_set().

Referenced by nat_incoming_invite_response(), and nat_on_rx_message().

{
   pjsip_dialog *dlg = pjsip_rdata_get_dlg(rdata);

   if (!endpoint) {
      return PJ_FALSE;
   }

   if (endpoint->nat.rewrite_contact) {
      /* rewrite_contact is intended to ensure we send requests/responses to
       * a routeable address when NAT is involved. The URI that dictates where
       * we send requests/responses can be determined either by Record-Route
       * headers or by the Contact header if no Record-Route headers are present.
       * We therefore will attempt to rewrite a Record-Route header first, and if
       * none are present, we fall back to rewriting the Contact header instead.
       */
      if (rewrite_route_set(rdata, dlg)) {
         rewrite_contact(rdata, dlg);
      }
   }

   if (endpoint->nat.force_rport) {
      rdata->msg_info.via->rport_param = rdata->pkt_info.src_port;
   }

   return PJ_FALSE;
}

load_module()

static int load_module ( void  )

static

Definition at line 538 of file res_pjsip_nat.c.

References ast_log, AST_MODFLAG_LOAD_ORDER, AST_MODPRI_APP_DEPEND, AST_MODULE_INFO(), AST_MODULE_LOAD_DECLINE, AST_MODULE_LOAD_SUCCESS, AST_MODULE_SUPPORT_CORE, ast_sip_register_service(), ast_sip_session_register_supplement, ASTERISK_GPL_KEY, LOG_ERROR, nat_module, and unload_module().

{
   if (ast_sip_register_service(&nat_module)) {
      ast_log(LOG_ERROR, "Could not register NAT module for incoming and outgoing requests\n");
      return AST_MODULE_LOAD_DECLINE;
   }

   ast_sip_session_register_supplement(&nat_supplement);

   return AST_MODULE_LOAD_SUCCESS;
}

nat_get_contact_sip_uri()

static pjsip_sip_uri* nat_get_contact_sip_uri ( pjsip_tx_data *  tdata )

static

Helper function which returns the SIP URI of a Contact header.

Definition at line 274 of file res_pjsip_nat.c.

References NULL.

Referenced by process_nat().

{
   pjsip_contact_hdr *contact = pjsip_msg_find_hdr(tdata->msg, PJSIP_H_CONTACT, NULL);

   if (!contact || (!PJSIP_URI_SCHEME_IS_SIP(contact->uri) && !PJSIP_URI_SCHEME_IS_SIPS(contact->uri))) {
      return NULL;
   }

   return pjsip_uri_get_uri(contact->uri);
}

nat_incoming_invite_request()

static int nat_incoming_invite_request ( struct ast_sip_session *  session, struct pjsip_rx_data *  rdata  )

static

Function called when an INVITE goes out.

Definition at line 498 of file res_pjsip_nat.c.

References ast_sip_session::inv_session, nat_module, and NULL.

{
   if (session->inv_session->state == PJSIP_INV_STATE_INCOMING) {
      pjsip_dlg_add_usage(session->inv_session->dlg, &nat_module, NULL);
   }

   return 0;
}

nat_incoming_invite_response()

static void nat_incoming_invite_response ( struct ast_sip_session *  session, struct pjsip_rx_data *  rdata  )

static

Function called when an INVITE response comes in.

Definition at line 508 of file res_pjsip_nat.c.

References ast_sip_session::endpoint, and handle_rx_message().

{
   handle_rx_message(session->endpoint, rdata);
}

nat_invoke_hook()

static int nat_invoke_hook ( void *  obj, void *  arg, int  flags  )

static

Callback function for invoking hooks.

Definition at line 294 of file res_pjsip_nat.c.

References ast_sip_nat_hook::outgoing_external_message, nat_hook_details::tdata, and nat_hook_details::transport.

Referenced by process_nat().

{
   struct ast_sip_nat_hook *hook = obj;
   struct nat_hook_details *details = arg;

   if (hook->outgoing_external_message) {
      hook->outgoing_external_message(details->tdata, details->transport);
   }

   return 0;
}

nat_on_rx_message()

static pj_bool_t nat_on_rx_message ( pjsip_rx_data *  rdata )

static

Definition at line 228 of file res_pjsip_nat.c.

References ao2_cleanup, ast_pjsip_rdata_get_endpoint(), and handle_rx_message().

{
   pj_bool_t res;
   struct ast_sip_endpoint *endpoint;

   endpoint = ast_pjsip_rdata_get_endpoint(rdata);
   res = handle_rx_message(endpoint, rdata);
   ao2_cleanup(endpoint);
   return res;
}

nat_on_tx_message()

static pj_status_t nat_on_tx_message ( pjsip_tx_data *  tdata )

static

Definition at line 477 of file res_pjsip_nat.c.

References process_nat(), and restore_orig_contact_host().

                                                           {
   pj_status_t rc;

   rc = process_nat(tdata);
   restore_orig_contact_host(tdata);

   return rc;
}

nat_outgoing_invite_request()

static void nat_outgoing_invite_request ( struct ast_sip_session *  session, struct pjsip_tx_data *  tdata  )

static

Function called when an INVITE comes in.

Definition at line 514 of file res_pjsip_nat.c.

References ast_sip_session::inv_session, nat_module, and NULL.

{
   if (session->inv_session->state == PJSIP_INV_STATE_NULL) {
      pjsip_dlg_add_usage(session->inv_session->dlg, &nat_module, NULL);
   }
}

process_nat()

static pj_status_t process_nat ( pjsip_tx_data *  tdata )

static

Definition at line 365 of file res_pjsip_nat.c.

References ao2_callback, ao2_cleanup, ast_debug, AST_RETRIEVE_FLAG_ALL, AST_RETRIEVE_FLAG_MULTIPLE, ast_sip_get_sorcery(), ast_sip_get_transport_states(), ast_sip_transport_is_local, ast_sockaddr_isnull(), ast_sockaddr_parse(), ast_sockaddr_set_port, ast_sockaddr_stringify_host(), ast_sorcery_retrieve_by_fields(), ast_sorcery_retrieve_by_id(), AST_TRANSPORT_TCP, AST_TRANSPORT_TLS, AST_TRANSPORT_UDP, request_transport_details::factory, find_transport_state_in_use(), request_transport_details::local_address, request_transport_details::local_port, nat_get_contact_sip_uri(), nat_invoke_hook(), NULL, PARSE_PORT_FORBID, RAII_VAR, nat_hook_details::tdata, request_transport_details::transport, transport_states, and request_transport_details::type.

Referenced by nat_on_tx_message().

{
   RAII_VAR(struct ao2_container *, transport_states, NULL, ao2_cleanup);
   RAII_VAR(struct ast_sip_transport *, transport, NULL, ao2_cleanup);
   RAII_VAR(struct ast_sip_transport_state *, transport_state, NULL, ao2_cleanup);
   struct request_transport_details details = { 0, };
   pjsip_via_hdr *via = NULL;
   struct ast_sockaddr addr = { { 0, } };
   pjsip_sip_uri *uri = NULL;
   RAII_VAR(struct ao2_container *, hooks, NULL, ao2_cleanup);

   /* If a transport selector is in use we know the transport or factory, so explicitly find it */
   if (tdata->tp_sel.type == PJSIP_TPSELECTOR_TRANSPORT) {
      details.transport = tdata->tp_sel.u.transport;
   } else if (tdata->tp_sel.type == PJSIP_TPSELECTOR_LISTENER) {
      details.factory = tdata->tp_sel.u.listener;
   } else if (tdata->tp_info.transport->key.type == PJSIP_TRANSPORT_UDP || tdata->tp_info.transport->key.type == PJSIP_TRANSPORT_UDP6) {
      /* Connectionless uses the same transport for all requests */
      details.type = AST_TRANSPORT_UDP;
      details.transport = tdata->tp_info.transport;
   } else {
      if (tdata->tp_info.transport->key.type == PJSIP_TRANSPORT_TCP) {
         details.type = AST_TRANSPORT_TCP;
      } else if (tdata->tp_info.transport->key.type == PJSIP_TRANSPORT_TLS) {
         details.type = AST_TRANSPORT_TLS;
      } else {
         /* Unknown transport type, we can't map and thus can't apply NAT changes */
         return PJ_SUCCESS;
      }

      if ((uri = nat_get_contact_sip_uri(tdata))) {
         details.local_address = uri->host;
         details.local_port = uri->port;
      } else if ((tdata->msg->type == PJSIP_REQUEST_MSG) &&
         (via = pjsip_msg_find_hdr(tdata->msg, PJSIP_H_VIA, NULL))) {
         details.local_address = via->sent_by.host;
         details.local_port = via->sent_by.port;
      } else {
         return PJ_SUCCESS;
      }

      if (!details.local_port) {
         details.local_port = (details.type == AST_TRANSPORT_TLS) ? 5061 : 5060;
      }
   }

   if (!(transport_states = ast_sip_get_transport_states())) {
      return PJ_SUCCESS;
   }

   if (!(transport_state = ao2_callback(transport_states, 0, find_transport_state_in_use, &details))) {
      return PJ_SUCCESS;
   }

   if (!(transport = ast_sorcery_retrieve_by_id(ast_sip_get_sorcery(), "transport", transport_state->id))) {
      return PJ_SUCCESS;
   }

   if (transport_state->localnet) {
      ast_sockaddr_parse(&addr, tdata->tp_info.dst_name, PARSE_PORT_FORBID);
      ast_sockaddr_set_port(&addr, tdata->tp_info.dst_port);

      /* See if where we are sending this request is local or not, and if not that we can get a Contact URI to modify */
      if (ast_sip_transport_is_local(transport_state, &addr)) {
         ast_debug(5, "Request is being sent to local address, skipping NAT manipulation\n");
         return PJ_SUCCESS;
      }
   }

   if (!ast_sockaddr_isnull(&transport_state->external_signaling_address)) {
      pjsip_cseq_hdr *cseq = PJSIP_MSG_CSEQ_HDR(tdata->msg);

      /* Update the Contact header with the external address. We only do this if
       * a CSeq is not present (which should not happen - but we are extra safe),
       * if a request is being sent, or if a response is sent that is not a response
       * to a REGISTER. We specifically don't do this for a response to a REGISTER
       * as the Contact headers would contain the registered Contacts, and not our
       * own Contact.
       */
      if (!cseq || tdata->msg->type == PJSIP_REQUEST_MSG ||
         pjsip_method_cmp(&cseq->method, &pjsip_register_method)) {
         /* We can only rewrite the URI when one is present */
         if (uri || (uri = nat_get_contact_sip_uri(tdata))) {
            pj_strdup2(tdata->pool, &uri->host, ast_sockaddr_stringify_host(&transport_state->external_signaling_address));
            if (transport->external_signaling_port) {
               uri->port = transport->external_signaling_port;
               ast_debug(4, "Re-wrote Contact URI port to %d\n", uri->port);
            }
         }
      }

      /* Update the via header if relevant */
      if ((tdata->msg->type == PJSIP_REQUEST_MSG) && (via || (via = pjsip_msg_find_hdr(tdata->msg, PJSIP_H_VIA, NULL)))) {
         pj_strdup2(tdata->pool, &via->sent_by.host, ast_sockaddr_stringify_host(&transport_state->external_signaling_address));
         if (transport->external_signaling_port) {
            via->sent_by.port = transport->external_signaling_port;
         }
      }
   }

   /* Invoke any additional hooks that may be registered */
   if ((hooks = ast_sorcery_retrieve_by_fields(ast_sip_get_sorcery(), "nat_hook", AST_RETRIEVE_FLAG_MULTIPLE | AST_RETRIEVE_FLAG_ALL, NULL))) {
      struct nat_hook_details hook_details = {
         .tdata = tdata,
         .transport = transport,
      };
      ao2_callback(hooks, 0, nat_invoke_hook, &hook_details);
   }

   return PJ_SUCCESS;
}

restore_orig_contact_host()

static void restore_orig_contact_host ( pjsip_tx_data *  tdata )

static

Definition at line 306 of file res_pjsip_nat.c.

References ast_debug, AST_SIP_X_AST_ORIG_HOST, AST_SIP_X_AST_ORIG_HOST_LEN, is_sip_uri, and NULL.

Referenced by nat_on_tx_message().

{
   pjsip_contact_hdr *contact;
   pj_str_t x_name = { AST_SIP_X_AST_ORIG_HOST, AST_SIP_X_AST_ORIG_HOST_LEN };
   pjsip_param *x_orig_host;
   pjsip_sip_uri *uri;
   pjsip_hdr *hdr;

   if (tdata->msg->type == PJSIP_REQUEST_MSG) {
      if (is_sip_uri(tdata->msg->line.req.uri)) {
         uri = pjsip_uri_get_uri(tdata->msg->line.req.uri);
         while ((x_orig_host = pjsip_param_find(&uri->other_param, &x_name))) {
            pj_list_erase(x_orig_host);
         }
      }
      for (hdr = tdata->msg->hdr.next; hdr != &tdata->msg->hdr; hdr = hdr->next) {
         if (hdr->type == PJSIP_H_TO) {
            if (is_sip_uri(((pjsip_fromto_hdr *) hdr)->uri)) {
               uri = pjsip_uri_get_uri(((pjsip_fromto_hdr *) hdr)->uri);
               while ((x_orig_host = pjsip_param_find(&uri->other_param, &x_name))) {
                  pj_list_erase(x_orig_host);
               }
            }
         }
      }
   }

   if (tdata->msg->type != PJSIP_RESPONSE_MSG) {
      return;
   }

   contact = pjsip_msg_find_hdr(tdata->msg, PJSIP_H_CONTACT, NULL);
   while (contact) {
      pjsip_sip_uri *contact_uri = pjsip_uri_get_uri(contact->uri);
      x_orig_host = pjsip_param_find(&contact_uri->other_param, &x_name);

      if (x_orig_host) {
         char host_port[x_orig_host->value.slen + 1];
         char *sep;

         ast_debug(1, "Restoring contact %.*s:%d  to %.*s\n", (int)contact_uri->host.slen,
            contact_uri->host.ptr, contact_uri->port,
            (int)x_orig_host->value.slen, x_orig_host->value.ptr);

         strncpy(host_port, x_orig_host->value.ptr, x_orig_host->value.slen);
         host_port[x_orig_host->value.slen] = '\0';
         sep = strchr(host_port, ':');
         if (sep) {
            *sep = '\0';
            sep++;
            pj_strdup2(tdata->pool, &contact_uri->host, host_port);
            contact_uri->port = strtol(sep, NULL, 10);
         }
         pj_list_erase(x_orig_host);
      }
      contact = pjsip_msg_find_hdr(tdata->msg, PJSIP_H_CONTACT, contact->next);
   }
}

rewrite_contact()

static int rewrite_contact ( pjsip_rx_data *  rdata, pjsip_dialog *  dlg  )

static

Definition at line 179 of file res_pjsip_nat.c.

References NULL, and rewrite_uri().

Referenced by handle_rx_message().

{
   pjsip_contact_hdr *contact;

   contact = pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_CONTACT, NULL);
   if (contact && !contact->star && (PJSIP_URI_SCHEME_IS_SIP(contact->uri) || PJSIP_URI_SCHEME_IS_SIPS(contact->uri))) {
      pjsip_sip_uri *uri = pjsip_uri_get_uri(contact->uri);

      rewrite_uri(rdata, uri, rdata->tp_info.pool);

      if (dlg && pj_list_empty(&dlg->route_set) && (!dlg->remote.contact
         || pjsip_uri_cmp(PJSIP_URI_IN_REQ_URI, dlg->remote.contact->uri, contact->uri))) {
         dlg->remote.contact = (pjsip_contact_hdr*)pjsip_hdr_clone(dlg->pool, contact);
         dlg->target = dlg->remote.contact->uri;
      }
      return 0;
   }

   return -1;
}

rewrite_route_set()

static int rewrite_route_set ( pjsip_rx_data *  rdata, pjsip_dialog *  dlg  )

static

Record-Route header has no meaning in REGISTER requests and should be ignored

There is currently no good way to get the dlg object for a pubsub dialog so we will just look at the rr & contact of the current message and hope for the best

Even if this message doesn't have any route headers the dialog may, so wait until a later invocation that has a dialog reference to make sure there isn't a previously saved routset in the dialog before deciding the contact needs to be modified

Definition at line 116 of file res_pjsip_nat.c.

References NULL, and rewrite_uri().

Referenced by handle_rx_message().

{
   pjsip_rr_hdr *rr = NULL;
   pjsip_sip_uri *uri;
   int res = -1;
   int ignore_rr = 0;
   int pubsub = 0;

   if (rdata->msg_info.msg->type == PJSIP_RESPONSE_MSG) {
      pjsip_hdr *iter;
      for (iter = rdata->msg_info.msg->hdr.prev; iter != &rdata->msg_info.msg->hdr; iter = iter->prev) {
         if (iter->type == PJSIP_H_RECORD_ROUTE) {
            rr = (pjsip_rr_hdr *)iter;
            break;
         }
      }
   } else if (pjsip_method_cmp(&rdata->msg_info.msg->line.req.method, &pjsip_register_method)) {
      rr = pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_RECORD_ROUTE, NULL);
   } else {
      /**
       * Record-Route header has no meaning in REGISTER requests
       * and should be ignored
       */
      ignore_rr = 1;
   }

   if (!pjsip_method_cmp(&rdata->msg_info.cseq->method, &pjsip_subscribe_method) ||
      !pjsip_method_cmp(&rdata->msg_info.cseq->method, &pjsip_notify_method)) {
      /**
       * There is currently no good way to get the dlg object for a pubsub dialog
       * so we will just look at the rr & contact of the current message and
       * hope for the best
       */
      pubsub = 1;
   }

   if (rr) {
      uri = pjsip_uri_get_uri(&rr->name_addr);
      rewrite_uri(rdata, uri, rdata->tp_info.pool);
      res = 0;
   }

   if (dlg && !pj_list_empty(&dlg->route_set) && !dlg->route_set_frozen) {
      pjsip_routing_hdr *route = dlg->route_set.next;
      uri = pjsip_uri_get_uri(&route->name_addr);
      rewrite_uri(rdata, uri, dlg->pool);
      res = 0;
   }

   if (!dlg && !rr && !ignore_rr  && !pubsub && rdata->msg_info.to->tag.slen){
      /**
       * Even if this message doesn't have any route headers
       * the dialog may, so wait until a later invocation that
       * has a dialog reference to make sure there isn't a
       * previously saved routset in the dialog before deciding
       * the contact needs to be modified
       */
      res = 0;
   }

   return res;
}

rewrite_uri()

static void rewrite_uri ( pjsip_rx_data *  rdata, pjsip_sip_uri *  uri, pj_pool_t *  pool  )

static

Definition at line 69 of file res_pjsip_nat.c.

References save_orig_contact_host().

Referenced by rewrite_contact(), and rewrite_route_set().

{

   if (pj_strcmp2(&uri->host, rdata->pkt_info.src_name) != 0) {
      save_orig_contact_host(rdata, uri);
   }

   pj_strdup2(pool, &uri->host, rdata->pkt_info.src_name);
   uri->port = rdata->pkt_info.src_port;
   if (!strcasecmp("WSS", rdata->tp_info.transport->type_name)) {
      /* WSS is special, we don't want to overwrite the URI at all as it needs to be ws */
   } else if (strcasecmp("udp", rdata->tp_info.transport->type_name)) {
      uri->transport_param = pj_str(rdata->tp_info.transport->type_name);
   } else {
      uri->transport_param.slen = 0;
   }
}

save_orig_contact_host()

static void save_orig_contact_host ( pjsip_rx_data *  rdata, pjsip_sip_uri *  uri  )

static

Definition at line 43 of file res_pjsip_nat.c.

References ast_debug, AST_SIP_X_AST_ORIG_HOST, COLON_LEN, and MAX_PORT_LEN.

Referenced by rewrite_uri().

{
   pjsip_param *x_orig_host;
   pj_str_t p_value;
#define COLON_LEN 1
#define MAX_PORT_LEN 5

   if (rdata->msg_info.msg->type != PJSIP_REQUEST_MSG ||
      rdata->msg_info.msg->line.req.method.id != PJSIP_REGISTER_METHOD) {
      return;
   }

   ast_debug(1, "Saving contact '%.*s:%d'\n",
      (int)uri->host.slen, uri->host.ptr, uri->port);

   x_orig_host = PJ_POOL_ALLOC_T(rdata->tp_info.pool, pjsip_param);
   x_orig_host->name = pj_strdup3(rdata->tp_info.pool, AST_SIP_X_AST_ORIG_HOST);
   p_value.slen = pj_strlen(&uri->host) + COLON_LEN + MAX_PORT_LEN;
   p_value.ptr = (char*)pj_pool_alloc(rdata->tp_info.pool, p_value.slen + 1);
   p_value.slen = snprintf(p_value.ptr, p_value.slen + 1, "%.*s:%d", (int)uri->host.slen, uri->host.ptr, uri->port);
   pj_strassign(&x_orig_host->value, &p_value);
   pj_list_insert_before(&uri->other_param, x_orig_host);

   return;
}

unload_module()

static int unload_module ( void  )

static

Definition at line 531 of file res_pjsip_nat.c.

References ast_sip_session_unregister_supplement(), ast_sip_unregister_service(), and nat_module.

Referenced by load_module().

{
   ast_sip_session_unregister_supplement(&nat_supplement);
   ast_sip_unregister_service(&nat_module);
   return 0;
}

Variable Documentation

__mod_info

struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "PJSIP NAT Support" , .key = "This paragraph is copyright (c) 2006 by Digium, Inc. \In order for your module to load, it must return this \key via a function called \"key\". Any code which \includes this paragraph must be licensed under the GNU \General Public License version 2 or later (at your \option). In addition to Digium's general reservations \of rights, Digium expressly reserves the right to \allow other parties to license this paragraph under \different terms. Any use of Digium, Inc. trademarks or \logos (including \"Asterisk\" or \"Digium\") without \express written permission of Digium, Inc. is prohibited.\n" , .buildopt_sum = "30ef0c93b36035ec78c9cfd712d36d9b" , .support_level = AST_MODULE_SUPPORT_CORE, .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_APP_DEPEND, .requires = "res_pjsip,res_pjsip_session", }

static

Definition at line 556 of file res_pjsip_nat.c.

ast_module_info

const struct ast_module_info* ast_module_info = &__mod_info

static

Definition at line 556 of file res_pjsip_nat.c.

nat_module

pjsip_module nat_module

static

Definition at line 487 of file res_pjsip_nat.c.

Referenced by load_module(), nat_incoming_invite_request(), nat_outgoing_invite_request(), and unload_module().

nat_supplement

struct ast_sip_session_supplement nat_supplement

static

Supplement for adding NAT functionality to dialog.

Definition at line 522 of file res_pjsip_nat.c.