xmpp Module

Andreea Spirea

   voice-system.ro

Edited by

Andreea Spirea

   Copyright © 2006 voice-system.ro
     __________________________________________________________

   Table of Contents
   1. User's Guide

        1.1. Overview
        1.2. Dependencies

              1.2.1. OpenSER Modules
              1.2.2. External Libraries or Applications

        1.3. Exported Parameters

              1.3.1. backend(string)
              1.3.2. domain_separator (string)
              1.3.3. gateway_domain (string)
              1.3.4. xmpp_domain (string)
              1.3.5. xmpp_host (string)
              1.3.6. xmpp_port (integer)
              1.3.7. xmpp_password (string)

        1.4. Exported Functions

              1.4.1. xmpp_send_message()

        1.5. Configuration

   2. Developer's Guide
   3. Frequently Asked Questions

   List of Examples
   1-1. Set backend parameter
   1-2. Set domain_separator parameter
   1-3. Set gateway_domain parameter
   1-4. Set xmpp_domain parameter
   1-5. Set xmpp_host parameter
   1-6. Set xmpp_port parameter
   1-7. Set xmpp_password parameter
   1-8. xmpp_send_message() usage
     __________________________________________________________

Chapter 1. User's Guide

1.1. Overview

   This module is a gateway between Openser and a XMPP/Jabber
   server. It enables the exchange of instant messages between SIP
   clients and XMPP(jabber) clients.

   The module can be used in two different modes:

     * XMPP Component Mode. In this mode, OpenSER connects to an
       XMPP server using the standardized XMPP component
       interface, extending your XMPP services. The connection is
       done over TCP/IP with authorization.
     * XMPP Server. In this mode, the OpenSER XMPP module is a
       stand-alone XMPP server, with no requirement for another
       XMPP server in the system. This server uses XMPP S2S
       (Server to Server) connections to connect to other XMPP
       servers or receive connections from other servers. NOTE:
       this is limited implementation of a XMPP server, it does
       not support SRV or TLS so far. This mode is in beta stage
       for the moment.

   In the component mode, you need a local XMPP server
   (recommended Jabberd2). The XMPP module will connect by using
   TCP/IP connection to the local jabber server. The documentation
   and the source for Jabberd server are located at the following
   link: http://jabberd.jabberstudio.org/2/#download

   After you have a running XMPP server, what you need to do is
   set the following parameters in the Openser configuration file:

     * gateway_domain, xmpp_domain (which can be the same as
       gateway_domain) and xmpp_host, which are explained in the
       Exported Parameters section;
     * listen = your ip;
     * alias=OpenSER SIP domain and alias=gateway domain;
     * in the following section of the configuration file, change
       to your gateway domain:

         ### ---8<--- cut here ---8<--- ###
        if (avp_check("$rd", "eq/s:sip-xmpp.openser.org")) {
                if (!t_newtran()) {
                        sl_reply_error();
        ...........

     * you can also define a password for the XMPP Component
       connection to the Jabber server, which must be the same as
       the xmpp_password parameter.

   A use case, for the component-mode, would look like this:

     * Openser is hosting the sip-server.openser.org SIP domain
     * The gateway SIP domain is sip-xmpp.openser.org
     * The XMPP server is hosting the XMPP domain xmpp.openser.org
     * The Component is hosting the XMPP domain
       xmpp-sip.openser.org

   In the XMPP stand-alone server mode, the XMPP module is a
   minimal XMPP/Jabber server. In this mode, another Jabber server
   is not needed. The gateway will connect to other XMPP servers
   basaed on the JID domain and by using the standardized XMPP S2S
   protocol.

   If you want to change to server-mode, you have to change the
   "backend" parameter, as shown in the Exported Parameters
   section, from "component" to "server".

   A use case, for the server-mode, would look like this:

     * Openser is hosting the SIP domain sip-server.openser.org
     * The gateway is hosting the SIP domain sip-xmpp.openser.org;
     * The "XMPP server" is running on xmpp-sip.openser.org.

   In both cases, the destination address must have the same
   pattern:

   "sip:username<delim>jabber_server@gateway_domain"

   From a jabber client's point of view, the destination will look
   like:

   "sip_username<delim>openser_domain@xmpp_domain"
     __________________________________________________________

1.2. Dependencies

1.2.1. OpenSER Modules

   The following modules must be loaded before this module:

     * requires 'tm' module.
     __________________________________________________________

1.2.2. External Libraries or Applications

   The following libraries or applications must be installed
   before running OpenSER with this module loaded:

     * expat - used for parsing/building XML. Linux package:
       libexpat1-devel
     __________________________________________________________

1.3. Exported Parameters

1.3.1. backend(string)

   The mode you are using the module; it can be either "component"
   or "server".

   Default value is "component".

   Example 1-1. Set backend parameter
...
 modparam("xmpp", "backend", "server");
...
     __________________________________________________________

1.3.2. domain_separator (string)

   In the destination address we need an extra character as a
   domain separator, apart from @. The address of the XMPP(jabber)
   client looks like this:
   "sip:username<domain_separator>jabber_server@gateway_domain".
   The address of a SIP client has the following pattern :
   "sip_username<domain_separator>openser_domain@xmpp_domain"; A
   common used character in XMPP transports is "%".

   Default value is "*".

   Example 1-2. Set domain_separator parameter
...
modparam("xmpp", "domain_separator", "%")
...
     __________________________________________________________

1.3.3. gateway_domain (string)

   The domain of the gateway, which must resolve in DNS. It must
   be the same with the gateway_domain from the destination
   address of the XMPP(jabber) client, as seen by the SIP client:
   "sip:username<delim>jjabber_server@gateway_domain".

   Default value is "sip-xmpp.openser.org".

   Example 1-3. Set gateway_domain parameter
...
 modparam("xmpp", "gateway_domain", "sip-xmpp.openser.org");
...
     __________________________________________________________

1.3.4. xmpp_domain (string)

   The XMPP domain of the component or the server, depending on
   the mode we are in. It can be the same as the gateway_domain.
   For a server DNS name, you need to add _xmpp-server._tcp SRV
   records in your DNS zone to enable connections from other XMPP
   servers.

   Default value is "sip-xmpp.openser.org".

   Example 1-4. Set xmpp_domain parameter
...
 modparam("xmpp", "xmpp_domain", "xmpp-sip.openser.org");
...
     __________________________________________________________

1.3.5. xmpp_host (string)

   The IP address or the name of the local XMPP/Jabber server, if
   the backend is set to "component". For server mode, this is the
   IP address the XMPP component binds to.

   Default value is "xmpp.openser.org".

   Example 1-5. Set xmpp_host parameter
...
 modparam("xmpp", "xmpp_host", "xmpp.openser.org");
...
     __________________________________________________________

1.3.6. xmpp_port (integer)

   In component mode, this is the port the XMPP server component
   interface listens to. In server mode, this is the port the
   server listens to.

   Default value is "5347", if backend is set to "component" and
   "5269", if backend is set to "server".

   Example 1-6. Set xmpp_port parameter
...
 modparam("xmpp", "xmpp_port", 5269);
...
     __________________________________________________________

1.3.7. xmpp_password (string)

   The password of the local XMPP server.

   This is the password for the component interface on the XMPP
   server, when connecting as a component. Default password is
   "secret". When connecting to jabberd2, you need to make sure
   this is the password configured in the file "c2s.xml". This is
   how the default configuration for the jabberd2 looks like:
                        <router>
        ...............
        <!-- Username/password to authenticate as --&gt;
    <user>jabberd</user>;          <!-- default: jabberd -->;
    <pass>secret</pass>;           <!-- default: secret -->;

   Example 1-7. Set xmpp_password parameter
...
 modparam("xmpp", "xmpp_password", "secret");
...
     __________________________________________________________

1.4. Exported Functions

1.4.1. xmpp_send_message()

   Converts SIP messages to XMPP(jabber) messages, in order to be
   relayed to a XMPP(jabber) client.

   Example 1-8. xmpp_send_message() usage
...
xmpp_send_massage();
...
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1.5. Configuration


   Next is presented a sample configuration file one can use to
   implement a standalone SIP-to-XMPP gateway. You can run an
   instance of OpenSER on a separate machine or on different port
   with the following config, and have the main SIP server
   configured to forward all SIP requests for XMPP world to it.
....
#
# $Id: README 5090 2008-10-17 16:49:49Z henningw $
#
# simple quick-start config script for XMPP GW
#
# make sure in your main SIP server that you send
# only the adequate SIP MESSAGES to XMPP GW
#
#
# ----------- global configuration parameters ------------------------

debug=9            # debug level (cmd line: -dddddddddd)
fork=no
log_stderror=yes    # (cmd line: -E)

/* Uncomment these lines to enter debugging mode
fork=no
log_stderror=yes
*/

check_via=no    # (cmd. line: -v)
dns=no          # (cmd. line: -r)
rev_dns=no      # (cmd. line: -R)
children=4

listen=udp:10.10.10.10:5076
alias=sip-xmpp.openser.org

# ------------------ module loading ----------------------------------

mpath="/opt/openser-1.1.0-xmpp/lib/openser/modules/"
loadmodule "sl.so"
loadmodule "tm.so"
loadmodule "rr.so"
loadmodule "maxfwd.so"
loadmodule "textops.so"
loadmodule "mi_fifo.so"


# XMPP
loadmodule "xmpp.so"

modparam("xmpp", "domain_separator", "*")
modparam("xmpp", "gateway_domain", "sip-xmpp.openser.org")
modparam("xmpp", "xmpp_domain", "xmpp-sip.openser.org")
modparam("xmpp", "xmpp_host", "xmpp.openser.org")

modparam("xmpp", "backend", "server")
# modparam("xmpp", "backend", "component")

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

# -- mi_fifo params --

modparam("mi_fifo", "fifo_name", "/tmp/openser_fifo_xmpp")

# -- usrloc params --

# -- rr params --
# add value to ;lr param to make some broken UAs happy
modparam("rr", "enable_full_lr", 1)

# -------------------------  request routing logic -------------------

# main routing logic

route{

        # initial sanity checks -- messages with
        # max_forwards==0, or excessively long requests
        if (!mf_process_maxfwd_header("10")) {
                sl_send_reply("483","Too Many Hops");
                exit;
        };

        if (msg:len >=  2048 ) {
                sl_send_reply("513", "Message too big");
                exit;
        };

        ### absorb retransmissions ###
        if (!t_newtran()) {
                sl_reply_error();
                return;
        }
        if (method == "MESSAGE") {
                log("*** xmpp-handled MESSAGE message.\n");
                if (xmpp_send_message()) {
                        t_reply("200", "Accepted");
                } else {
                        t_reply("404", "Not found");
                }
                return;
        }

        log("*** xmpp: unhandled message type\n");
        t_reply("503", "Service unavailable");
        return;
}


....
     __________________________________________________________

Chapter 2. Developer's Guide

   The module does not provide any API to use in other OpenSER
   modules.
     __________________________________________________________

Chapter 3. Frequently Asked Questions

   3.1. Where can I find more about OpenSER?
   3.2. Where can I post a question about this module?
   3.3. How can I report a bug?

   3.1. Where can I find more about OpenSER?

   Take a look at http://www.openser.org/.

   3.2. Where can I post a question about this module?

   First at all check if your question was already answered on one
   of our mailing lists:

     * User Mailing List -
       http://lists.openser.org/cgi-bin/mailman/listinfo/users
     * Developer Mailing List -
       http://lists.openser.org/cgi-bin/mailman/listinfo/devel

   E-mails regarding any stable OpenSER release should be sent to
   <users@lists.openser.org> and e-mails regarding development
   versions should be sent to <devel@lists.openser.org>.

   If you want to keep the mail private, send it to
   <team@lists.openser.org>.

   3.3. How can I report a bug?

   Please follow the guidelines provided at:
   http://sourceforge.net/tracker/?group_id=139143.
