--- 1/draft-ietf-uta-xmpp-03.txt 2014-11-26 19:15:45.228066641 -0800 +++ 2/draft-ietf-uta-xmpp-04.txt 2014-11-26 19:15:45.244067028 -0800 @@ -1,20 +1,20 @@ Network Working Group P. Saint-Andre Internet-Draft &yet Updates: 6120 (if approved) T. Alkemade Intended status: Standards Track -Expires: May 15, 2015 November 11, 2014 +Expires: May 30, 2015 November 26, 2014 Use of Transport Layer Security (TLS) in the Extensible Messaging and Presence Protocol (XMPP) - draft-ietf-uta-xmpp-03 + draft-ietf-uta-xmpp-04 Abstract This document provides recommendations for the use of Transport Layer Security (TLS) in the Extensible Messaging and Presence Protocol (XMPP). This document updates RFC 6120. Status of This Memo This Internet-Draft is submitted in full conformance with the @@ -23,21 +23,21 @@ Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on May 15, 2015. + This Internet-Draft will expire on May 30, 2015. Copyright Notice Copyright (c) 2014 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents @@ -52,21 +52,21 @@ 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 2 3. Recommendations . . . . . . . . . . . . . . . . . . . . . . . 3 3.1. Support for TLS . . . . . . . . . . . . . . . . . . . . . 3 3.2. Compression . . . . . . . . . . . . . . . . . . . . . . . 3 3.3. Session Resumption . . . . . . . . . . . . . . . . . . . 3 3.4. Authenticated Connections . . . . . . . . . . . . . . . . 3 3.5. Unauthenticated Connections . . . . . . . . . . . . . . . 4 3.6. Server Name Indication . . . . . . . . . . . . . . . . . 4 3.7. Human Factors . . . . . . . . . . . . . . . . . . . . . . 4 - 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4 + 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5 5. Security Considerations . . . . . . . . . . . . . . . . . . . 5 6. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 6.1. Normative References . . . . . . . . . . . . . . . . . . 5 6.2. Informative References . . . . . . . . . . . . . . . . . 6 Appendix A. Implementation Notes . . . . . . . . . . . . . . . . 7 Appendix B. Acknowledgements . . . . . . . . . . . . . . . . . . 7 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7 1. Introduction @@ -121,46 +121,51 @@ 3.2. Compression XMPP supports an application-layer compression technology [XEP-0138]. Although this XMPP extension might have slightly stronger security properties than TLS-layer compression (since it is enabled after SASL authentication, as described in [XEP-0170]), this document neither encourages nor discourages use of XMPP-layer compression. 3.3. Session Resumption - Use of session IDs [RFC5246] is RECOMMENDED instead of session - tickets [RFC5077], since XMPP does not in general use state - management technologies such as tickets or "cookies" [RFC6265]. - In XMPP, TLS session resumption can be used in concert with the XMPP Stream Management extension; see [XEP-0198] for further details. 3.4. Authenticated Connections Both the core XMPP specification [RFC6120] and the "CertID" specification [RFC6125] provide recommendations and requirements for certificate validation in the context of authenticated connections. This document does not supersede those specifications. Wherever possible, it is best to prefer authenticated connections (along with SASL [RFC4422]), as already stated in the core XMPP specification [RFC6120]. In particular, clients MUST authenticate servers. + Because this document does not mandate that servers need to + authenticate peer servers, unauthenticated server-to-server + connections are allowed (consistent with current practice on the XMPP + network). + + This document does not modify the recommendations in [RFC6120] + regarding the Subject Alternative Names (or other certificate + details) that need to be supported for authentication of XMPP + connections. 3.5. Unauthenticated Connections Given the pervasiveness of passive eavesdropping, even an unauthenticated connection might be better than an unencrypted connection (this is similar to the "better than nothing security" approach for IPsec [RFC5386]). In particular, because of current deployment challenges for authenticated connections between XMPP servers (see [I-D.ietf-xmpp-dna] and [I-D.ietf-xmpp-posh] for - details), it might be reasonable for XMPP server implementations to + details), it can be reasonable for XMPP server implementations to accept unauthenticated connections when the Server Dialback protocol [XEP-0220] is used for weak identity verification; this will at least enable encryption of server-to-server connections. Unauthenticated connections include connections negotiated using anonymous Diffie- Hellman algorithms or using self-signed certificates, among other scenarios. 3.6. Server Name Indication Although there is no harm in supporting the TLS Server Name @@ -226,24 +231,20 @@ Sheffer, Y., Holz, R., and P. Saint-Andre, "Recommendations for Secure Use of TLS and DTLS", draft- ietf-uta-tls-bcp-07 (work in progress), November 2014. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC4949] Shirey, R., "Internet Security Glossary, Version 2", RFC 4949, August 2007. - [RFC5077] Salowey, J., Zhou, H., Eronen, P., and H. Tschofenig, - "Transport Layer Security (TLS) Session Resumption without - Server-Side State", RFC 5077, January 2008. - [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security (TLS) Protocol Version 1.2", RFC 5246, August 2008. [RFC6120] Saint-Andre, P., "Extensible Messaging and Presence Protocol (XMPP): Core", RFC 6120, March 2011. [RFC6125] Saint-Andre, P. and J. Hodges, "Representation and Verification of Domain-Based Application Service Identity within Internet Public Key Infrastructure Using X.509 (PKIX) Certificates in the Context of Transport Layer @@ -273,23 +274,20 @@ [RFC4422] Melnikov, A. and K. Zeilenga, "Simple Authentication and Security Layer (SASL)", RFC 4422, June 2006. [RFC5386] Williams, N. and M. Richardson, "Better-Than-Nothing Security: An Unauthenticated Mode of IPsec", RFC 5386, November 2008. [RFC6066] Eastlake, D., "Transport Layer Security (TLS) Extensions: Extension Definitions", RFC 6066, January 2011. - [RFC6265] Barth, A., "HTTP State Management Mechanism", RFC 6265, - April 2011. - [XEP-0138] Hildebrand, J. and P. Saint-Andre, "Stream Compression", XSF XEP 0138, May 2009. [XEP-0170] Saint-Andre, P., "Recommended Order of Stream Feature Negotiation", XSF XEP 0170, January 2007. [XEP-0198] Karneges, J., Saint-Andre, P., Hildebrand, J., Forno, F.,