Server IP Check This specification defines a simple XMPP extension that enables a client to discover its external IP address. This XMPP Extension Protocol is copyright © 1999 – 2024 by the XMPP Standards Foundation (XSF). Permission is hereby granted, free of charge, to any person obtaining a copy of this specification (the "Specification"), to make use of the Specification without restriction, including without limitation the rights to implement the Specification in a software program, deploy the Specification in a network service, and copy, modify, merge, publish, translate, distribute, sublicense, or sell copies of the Specification, and to permit persons to whom the Specification is furnished to do so, subject to the condition that the foregoing copyright notice and this permission notice shall be included in all copies or substantial portions of the Specification. Unless separate permission is granted, modified works that are redistributed shall not contain misleading information regarding the authors, title, number, or publisher of the Specification, and shall not claim endorsement of the modified works by the authors, any organization or project to which the authors belong, or the XMPP Standards Foundation. ## NOTE WELL: This Specification is provided on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, express or implied, including, without limitation, any warranties or conditions of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. ## In no event and under no legal theory, whether in tort (including negligence), contract, or otherwise, unless required by applicable law (such as deliberate and grossly negligent acts) or agreed to in writing, shall the XMPP Standards Foundation or any author of this Specification be liable for damages, including any direct, indirect, special, incidental, or consequential damages of any character arising from, out of, or in connection with the Specification or the implementation, deployment, or other use of the Specification (including but not limited to damages for loss of goodwill, work stoppage, computer failure or malfunction, or any and all other commercial damages or losses), even if the XMPP Standards Foundation or such author has been advised of the possibility of such damages. This XMPP Extension Protocol has been contributed in full conformance with the XSF's Intellectual Property Rights Policy (a copy of which can be found at <https://xmpp.org/about/xsf/ipr-policy> or obtained by writing to XMPP Standards Foundation, P.O. Box 787, Parker, CO 80134 USA). 0279 Deferred Standards Track Standards Council XMPP Core sic Peter Saint-Andre stpeter@stpeter.im stpeter@jabber.org https://stpeter.im/ Diana Cionoiu diana@null.ro l-fy@jabber.null.ro Thiago Camargo thiago@xmppjingle.com barata7@gmail.com 0.2 2013-04-17 psa

Modified XML format so server can return port as well as IP address; incremented protocol version from 0 to 1.

 0.1 2010-03-05 psa

Initial published version.

 0.0.2 2009-03-10 psa

Removed client inclusion of its IP address; added IPv6 example.

 0.0.1 2009-03-10 psa

First draft.

There are times when a client might want or need to discover what its external Internet Protocol (IP) address and port are, e.g. when gathering transport candidates for protocols such as SOCKS5 Bytestreams (XEP-0065) XEP-0065: SOCKS5 Bytestreams <https://xmpp.org/extensions/xep-0065.html>. or Jingle ICE-UDP Transport Method (XEP-0176) XEP-0176: Jingle ICE-UDP Transport Method <https://xmpp.org/extensions/xep-0176.html>.. One way to do so is for the client to ask the XMPP server to which it has connected. This specification defines such a method. The information provided by the server cannot necessarily be relied upon because there might be intermediate entities between the client and the server, but if the IP address and port returned by the server is different from the client's notion of its IP address and port then at the very least the client has received a hint that it might be behind a network address translator (NAT) and therefore cannot usefully provide its private IP address as a candidate for use in multimedia negotiations.

First the client sends an IQ-get request to its server.

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The server then returns an IQ-result containing an <address/> element containing an <ip/> element specifying the client's external IP address and, optionally, a <port/> element specifying the client's external port.

192.168.4.1 12345 ]]>

Note that the IP address could be IPv4 or IPv6.

2001:db8::9:1 12345
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If an entity supports this protocol, it MUST report that by including a service discovery feature of "urn:xmpp:sic:1" in response to disco#info requests (see Protocol Namespaces regarding issuance of one or more permanent namespaces).

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XMPP Core RFC 6120: Extensible Messaging and Presence Protocol (XMPP): Core <http://tools.ietf.org/html/rfc6120>. specifies that client IP addresses shall not be made public. If a client requests its own IP address, that policy is not violated. However, a server MUST NOT return the IP address of another client (e.g., if a connected client sends a SIC request to the bare JID of another user); instead, it MUST return a <forbidden/> error.

This document requires no interaction with the Internet Assigned Numbers Authority (IANA) The Internet Assigned Numbers Authority (IANA) is the central coordinator for the assignment of unique parameter values for Internet protocols, such as port numbers and URI schemes. For further information, see <http://www.iana.org/>..

This specification defines the following XML namespace:

  • urn:xmpp:sic:1

Upon advancement of this specification from a status of Experimental to a status of Draft, the XMPP Registrar The XMPP Registrar maintains a list of reserved protocol namespaces as well as registries of parameters used in the context of XMPP extension protocols approved by the XMPP Standards Foundation. For further information, see <https://xmpp.org/registrar/>. shall add the foregoing namespace to the registry located at <https://xmpp.org/registrar/namespaces.html>, as described in Section 4 of XMPP Registrar Function (XEP-0053) XEP-0053: XMPP Registrar Function <https://xmpp.org/extensions/xep-0053.html>..

If the protocol defined in this specification undergoes a revision that is not fully backwards-compatible with an older version, the XMPP Registrar shall increment the protocol version number found at the end of the XML namespaces defined herein, as described in Section 4 of XEP-0053.

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Thanks to Joe Hildebrand for his feedback.