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<table summary="layout" cellpadding="0" cellspacing="2" class="TOCbug" align="right"><tr><td class="TOCbug"><a href="#toc"> TOC </a></td></tr></table>
<table summary="layout" width="66%" border="0" cellpadding="0" cellspacing="0"><tr><td><table summary="layout" width="100%" border="0" cellpadding="2" cellspacing="1">
<tr><td class="header">Network Working Group</td><td class="header">S. Josefsson</td></tr>
<tr><td class="header">Internet-Draft</td><td class="header">SJD AB</td></tr>
<tr><td class="header">Intended status: Informational</td><td class="header">June 16, 2011</td></tr>
<tr><td class="header">Expires: December 18, 2011</td><td class="header"> </td></tr>
</table></td></tr></table>
<h1><br />Design Guide for SASL and GSS-API Mechanisms<br />draft-josefsson-sasl-gssapi-mech-design-00rc1</h1>
<h3>Abstract</h3>
<p>SASL and GSS-API are two security frameworks that are linked
together by the GS2 mechanism. This document is intended to
help designers of future SASL and GSS-API security mechanisms
write better mechanism specifications.
</p>
<h3>Status of this Memo</h3>
<p>
This Internet-Draft is submitted in full
conformance with the provisions of BCP 78 and BCP 79.</p>
<p>
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/.</p>
<p>
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.”</p>
<p>
This Internet-Draft will expire on December 18, 2011.</p>
<h3>Copyright Notice</h3>
<p>
Copyright (c) 2011 IETF Trust and the persons identified as the
document authors. All rights reserved.</p>
<p>
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
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.</p>
<a name="toc"></a><br /><hr />
<h3>Table of Contents</h3>
<p class="toc">
<a href="#intro">1.</a>
Introduction<br />
<a href="#issues-sasl">2.</a>
Issues for SASL mechanisms<br />
<a href="#client-first">2.1.</a>
Client-First<br />
<a href="#assigning-an-oid">2.2.</a>
Assigning an OID<br />
<a href="#anchor1">2.3.</a>
The GS2 header<br />
<a href="#zero-length-messages">2.4.</a>
Zero Length Messages<br />
<a href="#per-message-tokens">2.5.</a>
Per-Message Tokens<br />
<a href="#pseudo-random">2.6.</a>
GSS_Pseudo_random<br />
<a href="#gssapi-mech-attributes">2.7.</a>
GSS-API Mechanism Attributes<br />
<a href="#issues-gssapi">3.</a>
Issues for GSS-API mechanisms<br />
<a href="#mutual-auth-and-cb">3.1.</a>
Mutual Authentication and Channel Binding<br />
<a href="#sasl-name">3.2.</a>
Allocate a SASL mechanism name<br />
<a href="#ack">4.</a>
Acknowledgements<br />
<a href="#iana">5.</a>
IANA Considerations<br />
<a href="#security">6.</a>
Security Considerations<br />
<a href="#rfc.references1">7.</a>
References<br />
<a href="#rfc.authors">§</a>
Author's Address<br />
</p>
<br clear="all" />
<a name="intro"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="TOCbug" align="right"><tr><td class="TOCbug"><a href="#toc"> TOC </a></td></tr></table>
<a name="rfc.section.1"></a><h3>1.
Introduction</h3>
<p>The Generic Security Service Application Program Interface
(GSS-API) <a class='info' href='#RFC2743'>[RFC2743]<span> (</span><span class='info'>Linn, J., “Generic Security Service Application Program Interface Version 2, Update 1,” January 2000.</span><span>)</span></a> is a framework that provides
security services to applications using a variety of
authentication mechanisms. There are widely implemented C
bindings <a class='info' href='#RFC2744'>[RFC2744]<span> (</span><span class='info'>Wray, J., “Generic Security Service API Version 2 : C-bindings,” January 2000.</span><span>)</span></a> of the abstract interface.
</p>
<p>Simple Authentication and Security Layer (SASL) <a class='info' href='#RFC4422'>[RFC4422]<span> (</span><span class='info'>Melnikov, A. and K. Zeilenga, “Simple Authentication and Security Layer (SASL),” June 2006.</span><span>)</span></a> is a framework to provide authentication
and security layers for connection-based protocols, also using a
variety of mechanisms.
</p>
<p>The <a class='info' href='#RFC5801'>GS2 mechanism bridge
framework<span> (</span><span class='info'>Josefsson, S. and N. Williams, “Using Generic Security Service Application Program Interface (GSS-API) Mechanisms in Simple Authentication and Security Layer (SASL): The GS2 Mechanism Family,” July 2010.</span><span>)</span></a> [RFC5801] describes how every GSS-API mechanisms can be
used as a SASL mechanism. Indirectly, the document also
describes how a SASL mechanism (if designed carefully) can be a
GSS-API mechanism. The purpose of this document is to
expand the "if designed carefully" remark.
</p>
<p>We also mention issues for designers of native GSS-API
mechanisms, so that they work as smoothly as possible with SASL
applications.
</p>
<p>The hope is that future SASL mechanisms will (when possible) be
designed in a way so that they are valid GSS-API mechanisms that
are used in SASL through GS2. Understanding the issues and
following the recommendations in this document will hopefully
make this an easy and wortwhile task.
</p>
<p>The document uses terms from <a class='info' href='#RFC2743'>[RFC2743]<span> (</span><span class='info'>Linn, J., “Generic Security Service Application Program Interface Version 2, Update 1,” January 2000.</span><span>)</span></a>, <a class='info' href='#RFC2744'>[RFC2744]<span> (</span><span class='info'>Wray, J., “Generic Security Service API Version 2 : C-bindings,” January 2000.</span><span>)</span></a> and <a class='info' href='#RFC4422'>[RFC4422]<span> (</span><span class='info'>Melnikov, A. and K. Zeilenga, “Simple Authentication and Security Layer (SASL),” June 2006.</span><span>)</span></a>.
</p>
<a name="issues-sasl"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="TOCbug" align="right"><tr><td class="TOCbug"><a href="#toc"> TOC </a></td></tr></table>
<a name="rfc.section.2"></a><h3>2.
Issues for SASL mechanisms</h3>
<p>This section discusses issues concerning designers of SASL
mechanism, so that their SASL mechanisms may be used as
GSS-API mechanisms as well.
</p>
<a name="client-first"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="TOCbug" align="right"><tr><td class="TOCbug"><a href="#toc"> TOC </a></td></tr></table>
<a name="rfc.section.2.1"></a><h3>2.1.
Client-First</h3>
<p>GSS-API and GS2 mechanisms always have client-initiated
authentication message exchanges, in SASL terms, thus any SASL
mechanism that wants to be the equivalent of a GSS-API
mechanism that is wire compatible when used under GS2, also
needs to be client-initiated. For some mechanisms this may
mean having a constant initial authentication message.
</p>
<a name="assigning-an-oid"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="TOCbug" align="right"><tr><td class="TOCbug"><a href="#toc"> TOC </a></td></tr></table>
<a name="rfc.section.2.2"></a><h3>2.2.
Assigning an OID</h3>
<p>Every GSS-API mechanism is identified by an OID. For
example, the OID for the SCRAM-SHA-1 mechanism (<a class='info' href='#RFC5802'>[RFC5802]<span> (</span><span class='info'>Newman, C., Menon-Sen, A., Melnikov, A., and N. Williams, “Salted Challenge Response Authentication Mechanism (SCRAM) SASL and GSS-API Mechanisms,” July 2010.</span><span>)</span></a>) is 1.3.6.1.5.5.14.
</p>
<p>Thus, SASL mechanisms should have an OID allocated for them
so they can used as GSS-API mechanisms.
</p>
<p>For SASL mechanism families, it is difficult to say anything
in general. Often the mechanism family concept is used to
provide for negotiation of cryptographic algorithms
(particularly for hash agility). It is natural for each
member of the mechanism family to have its own OID arc from
which OIDs are assigned.
</p>
<a name="anchor1"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="TOCbug" align="right"><tr><td class="TOCbug"><a href="#toc"> TOC </a></td></tr></table>
<a name="rfc.section.2.3"></a><h3>2.3.
The GS2 header</h3>
<p>All initial GSS-API security context tokens normally start
with a DER encoded header bearing the OID of the selected
mechanism (see section 3.1 of <a class='info' href='#RFC5802'>[RFC5802]<span> (</span><span class='info'>Newman, C., Menon-Sen, A., Melnikov, A., and N. Williams, “Salted Challenge Response Authentication Mechanism (SCRAM) SASL and GSS-API Mechanisms,” July 2010.</span><span>)</span></a>). The
GSS-API header also includes a DER-encoded length of the rest
of the security context token. Because this header is not
neither constant, nor easy to encode nor decode, GS2 removes
this header, and replaces it with a header given by a
"gs2-header" ABNF production, see section 4 of <a class='info' href='#RFC5801'>[RFC5801]<span> (</span><span class='info'>Josefsson, S. and N. Williams, “Using Generic Security Service Application Program Interface (GSS-API) Mechanisms in Simple Authentication and Security Layer (SASL): The GS2 Mechanism Family,” July 2010.</span><span>)</span></a>. The syntax of the "gs2-header" is
briefly as follows (NOTE: this is an INFORMATIVE copy):
</p><div style='display: table; width: 0; margin-left: 3em; margin-right: auto'><pre>
gs2-nonstd-flag = "F"
;; "F" means the mechanism is not a
;; standard GSS-API mechanism in that the
;; RFC 2743, Section 3.1 header was missing
gs2-cb-flag = ("p=" cb-name) / "n" / "y"
;; GS2 channel binding (CB) flag
;; "p" -> client supports and used CB
;; "n" -> client does not support CB
;; "y" -> client supports CB, thinks the
;; server does not
gs2-authzid = "a=" saslname
;; GS2 has to transport an authzid since
;; the GSS-API has no equivalent
gs2-header = [gs2-nonstd-flag ","] gs2-cb-flag "," [gs2-authzid] ","
</pre></div>
<p>Therefore, to be GS2 compatible, the first client
authentication message for a SASL mechanism should begin
with the "gs2-header".
</p>
<a name="zero-length-messages"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="TOCbug" align="right"><tr><td class="TOCbug"><a href="#toc"> TOC </a></td></tr></table>
<a name="rfc.section.2.4"></a><h3>2.4.
Zero Length Messages</h3>
<p>Some SASL mechanisms use zero-length messages to indicate
completion of some step when there's no additional data to
send to the peer. The GSS-API specification <a class='info' href='#RFC2743'>[RFC2743]<span> (</span><span class='info'>Linn, J., “Generic Security Service Application Program Interface Version 2, Update 1,” January 2000.</span><span>)</span></a> contains the following sentence:
</p>
<div style='display: table; width: 0; margin-left: 3em; margin-right: auto'><pre>
Zero-length tokens are never returned by GSS routines
for transfer to a peer.
</pre></div><p>
Thus any SASL mechanism that wishes to be a GSS-API mechanism
cannot use zero-length messages. Instead, for example, the
mechanism can send a constant, one-octet message.
</p>
<a name="per-message-tokens"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="TOCbug" align="right"><tr><td class="TOCbug"><a href="#toc"> TOC </a></td></tr></table>
<a name="rfc.section.2.5"></a><h3>2.5.
Per-Message Tokens</h3>
<p>GSS-API mechanisms typically provide applications the ability
to protect (integrity and confidentiality) arbitrary data
after the security context has been negotiated. If your SASL
mechanism is able to derive shared symmetric keys, it is
possible to specify how per-message GSS-API tokens would
work.
</p>
<p>A simple way to achieve this is to re-use the per-message
tokens of the <a class='info' href='#RFC4121'>Kerberos V5 GSS-API
mechanism<span> (</span><span class='info'>Zhu, L., Jaganathan, K., and S. Hartman, “The Kerberos Version 5 Generic Security Service Application Program Interface (GSS-API) Mechanism: Version 2,” July 2005.</span><span>)</span></a> [RFC4121], using a specific <a class='info' href='#RFC3961'>Kerberos V enctype<span> (</span><span class='info'>Raeburn, K., “Encryption and Checksum Specifications for Kerberos 5,” February 2005.</span><span>)</span></a> [RFC3961] (currently the
strongest enctype is based on AES <a class='info' href='#RFC3962'>[RFC3962]<span> (</span><span class='info'>Raeburn, K., “Advanced Encryption Standard (AES) Encryption for Kerberos 5,” February 2005.</span><span>)</span></a>. The mechanism
specification must also specify how to obtain two "protocol"
keys, one for each direction. For example, see section 8.2 of
<a class='info' href='#RFC5802'>[RFC5802]<span> (</span><span class='info'>Newman, C., Menon-Sen, A., Melnikov, A., and N. Williams, “Salted Challenge Response Authentication Mechanism (SCRAM) SASL and GSS-API Mechanisms,” July 2010.</span><span>)</span></a>.
</p>
<a name="pseudo-random"></a><br /><hr />
<table summary="layout" cellpadding="0" cellspacing="2" class="TOCbug" align="right"><tr><td class="TOCbug"><a href="#toc"> TOC </a></td></tr></table>
<a name="rfc.section.2.6"></a><h3>2.6.
GSS_Pseudo_random</h3>
<p>The GSS_Pseudo_random facility <a class='info' href='#RFC4401'>[RFC4401]<span> (</span><span class='info'>Williams, N., “A Pseudo-Random Function (PRF) API Extension for the Generic Security Service Application Program Interface (GSS-API),” February 2006.</span><span>)</span></a>
provides GSS-API applications an interface to a
mechanism-specific PRF. If your SASL mechanism is able to
derive any shared symmetric keys, it is possible to have the
corresponding GSS-API mechanism support GSS_Pseudo_random. A
simple way to achieve this is to re-use the <a class='info' href='#RFC4402'>Kerberos V PRF<span> (</span><span class='info'>Williams, N., “A Pseudo-Random Function (PRF) for the Kerberos V Generic Security Service Application Program Interface (GSS-API) Mechanism,” February 2006.</span><span>)</span></a> [RFC4402]. For example, see
section 8.3 of <a class='info' href='#RFC5802'>[RFC5802]<span> (</span><span class='info'>Newman, C., Menon-Sen, A., Melnikov, A., and N. Williams, “Salted Challenge Response Authentication Mechanism (SCRAM) SASL and GSS-API Mechanisms,” July 2010.</span><span>)</span></a>.
</p>
<a name="gssapi-mech-attributes"></a><br /><hr />
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<a name="rfc.section.2.7"></a><h3>2.7.
GSS-API Mechanism Attributes</h3>
<p>Indicating what <a class='info' href='#RFC5587'>[RFC5587]<span> (</span><span class='info'>Williams, N., “Extended Generic Security Service Mechanism Inquiry APIs,” July 2009.</span><span>)</span></a> attributes the
resulting GSS-API mechanism will have is useful for GSS-API
application writers. Standards-track GSS mechanisms MUST have
the GSS_C_MA_ITOK_FRAMED attribute. The set of attributes
usually include GSS_C_MA_MECH_CONCRETE, GSS_C_MA_ITOK_FRAMED,
GSS_C_MA_AUTH_INIT, GSS_C_MA_AUTH_TARG (if mutual
authentication is supported), and GSS_C_MA_CBINDINGS.
</p>
<a name="issues-gssapi"></a><br /><hr />
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<a name="rfc.section.3"></a><h3>3.
Issues for GSS-API mechanisms</h3>
<a name="mutual-auth-and-cb"></a><br /><hr />
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<a name="rfc.section.3.1"></a><h3>3.1.
Mutual Authentication and Channel Binding</h3>
<p>It is highly desirable that GSS-API and SASL mechanisms
support mutual authentication and <a class='info' href='#RFC5056'>channel binding<span> (</span><span class='info'>Williams, N., “On the Use of Channel Bindings to Secure Channels,” November 2007.</span><span>)</span></a> [RFC5056].
</p>
<p>SASL mechanisms that support channel binding must prefix the
gs2-header <a class='info' href='#RFC5801'>[RFC5801]<span> (</span><span class='info'>Josefsson, S. and N. Williams, “Using Generic Security Service Application Program Interface (GSS-API) Mechanisms in Simple Authentication and Security Layer (SASL): The GS2 Mechanism Family,” July 2010.</span><span>)</span></a> to the
application-provided channel bindings data.
</p>
<a name="sasl-name"></a><br /><hr />
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<a name="rfc.section.3.2"></a><h3>3.2.
Allocate a SASL mechanism name</h3>
<p>The GSS_Inquire_SASLname_for_mech and
GSS_Inquire_mech_for_SASLname calls are used to map between
SASL mechanism name and GSS-API mechanism OID.
</p>
<p>For this reason, new GSS-API mechanisms should specify a SASL
mechanism name conforming to the syntactical rules in <a class='info' href='#RFC4422'>[RFC4422]<span> (</span><span class='info'>Melnikov, A. and K. Zeilenga, “Simple Authentication and Security Layer (SASL),” June 2006.</span><span>)</span></a>. If a SASL name is not specified, then
the mechanism's SASL name will be derived from its GSS-API
mechanism OID by hashing it.
</p>
<a name="ack"></a><br /><hr />
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<a name="rfc.section.4"></a><h3>4.
Acknowledgements</h3>
<p>The need for this document grow out of the authors'
contributions to <a class='info' href='#I-D.ietf-kitten-sasl-openid'>[I‑D.ietf‑kitten‑sasl‑openid]<span> (</span><span class='info'>Lear, E., Tschofenig, H., Mauldin, H., and S. Josefsson, “A SASL & GSS-API Mechanism for OpenID,” June 2011.</span><span>)</span></a>,
<a class='info' href='#I-D.ietf-kitten-sasl-saml'>[I‑D.ietf‑kitten‑sasl‑saml]<span> (</span><span class='info'>Wierenga, K., Lear, E., and S. Josefsson, “A SASL and GSS-API Mechanism for SAML,” June 2011.</span><span>)</span></a>, and <a class='info' href='#I-D.cantor-ietf-kitten-saml-ec'>[I‑D.cantor‑ietf‑kitten‑saml‑ec]<span> (</span><span class='info'>Cantor, S. and S. Josefsson, “SAML Enhanced Client SASL and GSS-API Mechanisms,” March 2011.</span><span>)</span></a> and discussions
involving Eliot Lear, Alexey Melnikov, Sam Hartman, Nico
Williams, and Simon Josefsson. Several of the recommendations
in this documented were inspired by the solution used for <a class='info' href='#RFC5802'>SCRAM<span> (</span><span class='info'>Newman, C., Menon-Sen, A., Melnikov, A., and N. Williams, “Salted Challenge Response Authentication Mechanism (SCRAM) SASL and GSS-API Mechanisms,” July 2010.</span><span>)</span></a> [RFC5802].
</p>
<a name="iana"></a><br /><hr />
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<a name="rfc.section.5"></a><h3>5.
IANA Considerations</h3>
<p>None.
</p>
<a name="security"></a><br /><hr />
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<a name="rfc.section.6"></a><h3>6.
Security Considerations</h3>
<p>The security considerations of GSS-API and SASL are discussed
in their respective specifications (<a class='info' href='#RFC2743'>[RFC2743]<span> (</span><span class='info'>Linn, J., “Generic Security Service Application Program Interface Version 2, Update 1,” January 2000.</span><span>)</span></a>,
<a class='info' href='#RFC2744'>[RFC2744]<span> (</span><span class='info'>Wray, J., “Generic Security Service API Version 2 : C-bindings,” January 2000.</span><span>)</span></a>, and <a class='info' href='#RFC4422'>[RFC4422]<span> (</span><span class='info'>Melnikov, A. and K. Zeilenga, “Simple Authentication and Security Layer (SASL),” June 2006.</span><span>)</span></a>). Also
applicable are the security considerations of GS2 <a class='info' href='#RFC5801'>[RFC5801]<span> (</span><span class='info'>Josefsson, S. and N. Williams, “Using Generic Security Service Application Program Interface (GSS-API) Mechanisms in Simple Authentication and Security Layer (SASL): The GS2 Mechanism Family,” July 2010.</span><span>)</span></a> and channel binding <a class='info' href='#RFC5056'>[RFC5056]<span> (</span><span class='info'>Williams, N., “On the Use of Channel Bindings to Secure Channels,” November 2007.</span><span>)</span></a>
</p>
<a name="rfc.references1"></a><br /><hr />
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<h3>7. References</h3>
<table width="99%" border="0">
<tr><td class="author-text" valign="top"><a name="RFC2743">[RFC2743]</a></td>
<td class="author-text"><a href="mailto:[email protected]">Linn, J.</a>, “<a href="http://tools.ietf.org/html/rfc2743">Generic Security Service Application Program Interface Version 2, Update 1</a>,” RFC 2743, January 2000 (<a href="http://www.rfc-editor.org/rfc/rfc2743.txt">TXT</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC2744">[RFC2744]</a></td>
<td class="author-text"><a href="mailto:[email protected]">Wray, J.</a>, “<a href="http://tools.ietf.org/html/rfc2744">Generic Security Service API Version 2 : C-bindings</a>,” RFC 2744, January 2000 (<a href="http://www.rfc-editor.org/rfc/rfc2744.txt">TXT</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3961">[RFC3961]</a></td>
<td class="author-text">Raeburn, K., “<a href="http://tools.ietf.org/html/rfc3961">Encryption and Checksum Specifications for Kerberos 5</a>,” RFC 3961, February 2005 (<a href="http://www.rfc-editor.org/rfc/rfc3961.txt">TXT</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC3962">[RFC3962]</a></td>
<td class="author-text">Raeburn, K., “<a href="http://tools.ietf.org/html/rfc3962">Advanced Encryption Standard (AES) Encryption for Kerberos 5</a>,” RFC 3962, February 2005 (<a href="http://www.rfc-editor.org/rfc/rfc3962.txt">TXT</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC4121">[RFC4121]</a></td>
<td class="author-text">Zhu, L., Jaganathan, K., and S. Hartman, “<a href="http://tools.ietf.org/html/rfc4121">The Kerberos Version 5 Generic Security Service Application Program Interface (GSS-API) Mechanism: Version 2</a>,” RFC 4121, July 2005 (<a href="http://www.rfc-editor.org/rfc/rfc4121.txt">TXT</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC4401">[RFC4401]</a></td>
<td class="author-text">Williams, N., “<a href="http://tools.ietf.org/html/rfc4401">A Pseudo-Random Function (PRF) API Extension for the Generic Security Service Application Program Interface (GSS-API)</a>,” RFC 4401, February 2006 (<a href="http://www.rfc-editor.org/rfc/rfc4401.txt">TXT</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC4402">[RFC4402]</a></td>
<td class="author-text">Williams, N., “<a href="http://tools.ietf.org/html/rfc4402">A Pseudo-Random Function (PRF) for the Kerberos V Generic Security Service Application Program Interface (GSS-API) Mechanism</a>,” RFC 4402, February 2006 (<a href="http://www.rfc-editor.org/rfc/rfc4402.txt">TXT</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC4422">[RFC4422]</a></td>
<td class="author-text">Melnikov, A. and K. Zeilenga, “<a href="http://tools.ietf.org/html/rfc4422">Simple Authentication and Security Layer (SASL)</a>,” RFC 4422, June 2006 (<a href="http://www.rfc-editor.org/rfc/rfc4422.txt">TXT</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC5056">[RFC5056]</a></td>
<td class="author-text">Williams, N., “<a href="http://tools.ietf.org/html/rfc5056">On the Use of Channel Bindings to Secure Channels</a>,” RFC 5056, November 2007 (<a href="http://www.rfc-editor.org/rfc/rfc5056.txt">TXT</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC5587">[RFC5587]</a></td>
<td class="author-text">Williams, N., “<a href="http://tools.ietf.org/html/rfc5587">Extended Generic Security Service Mechanism Inquiry APIs</a>,” RFC 5587, July 2009 (<a href="http://www.rfc-editor.org/rfc/rfc5587.txt">TXT</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC5801">[RFC5801]</a></td>
<td class="author-text">Josefsson, S. and N. Williams, “<a href="http://tools.ietf.org/html/rfc5801">Using Generic Security Service Application Program Interface (GSS-API) Mechanisms in Simple Authentication and Security Layer (SASL): The GS2 Mechanism Family</a>,” RFC 5801, July 2010 (<a href="http://www.rfc-editor.org/rfc/rfc5801.txt">TXT</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="RFC5802">[RFC5802]</a></td>
<td class="author-text">Newman, C., Menon-Sen, A., Melnikov, A., and N. Williams, “<a href="http://tools.ietf.org/html/rfc5802">Salted Challenge Response Authentication Mechanism (SCRAM) SASL and GSS-API Mechanisms</a>,” RFC 5802, July 2010 (<a href="http://www.rfc-editor.org/rfc/rfc5802.txt">TXT</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="I-D.ietf-kitten-sasl-openid">[I-D.ietf-kitten-sasl-openid]</a></td>
<td class="author-text">Lear, E., Tschofenig, H., Mauldin, H., and S. Josefsson, “<a href="http://tools.ietf.org/html/draft-ietf-kitten-sasl-openid-03">A SASL & GSS-API Mechanism for OpenID</a>,” draft-ietf-kitten-sasl-openid-03 (work in progress), June 2011 (<a href="http://www.ietf.org/internet-drafts/draft-ietf-kitten-sasl-openid-03.txt">TXT</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="I-D.ietf-kitten-sasl-saml">[I-D.ietf-kitten-sasl-saml]</a></td>
<td class="author-text">Wierenga, K., Lear, E., and S. Josefsson, “<a href="http://tools.ietf.org/html/draft-ietf-kitten-sasl-saml-03">A SASL and GSS-API Mechanism for SAML</a>,” draft-ietf-kitten-sasl-saml-03 (work in progress), June 2011 (<a href="http://www.ietf.org/internet-drafts/draft-ietf-kitten-sasl-saml-03.txt">TXT</a>, <a href="http://www.ietf.org/internet-drafts/draft-ietf-kitten-sasl-saml-03.pdf">PDF</a>).</td></tr>
<tr><td class="author-text" valign="top"><a name="I-D.cantor-ietf-kitten-saml-ec">[I-D.cantor-ietf-kitten-saml-ec]</a></td>
<td class="author-text">Cantor, S. and S. Josefsson, “<a href="http://tools.ietf.org/html/draft-cantor-ietf-kitten-saml-ec-01">SAML Enhanced Client SASL and GSS-API Mechanisms</a>,” draft-cantor-ietf-kitten-saml-ec-01 (work in progress), March 2011 (<a href="http://www.ietf.org/internet-drafts/draft-cantor-ietf-kitten-saml-ec-01.txt">TXT</a>).</td></tr>
</table>
<a name="rfc.authors"></a><br /><hr />
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<h3>Author's Address</h3>
<table width="99%" border="0" cellpadding="0" cellspacing="0">
<tr><td class="author-text"> </td>
<td class="author-text">Simon Josefsson</td></tr>
<tr><td class="author-text"> </td>
<td class="author-text">SJD AB</td></tr>
<tr><td class="author-text"> </td>
<td class="author-text">Hagagatan 24</td></tr>
<tr><td class="author-text"> </td>
<td class="author-text">Stockholm 113 47</td></tr>
<tr><td class="author-text"> </td>
<td class="author-text">SE</td></tr>
<tr><td class="author" align="right">Email: </td>
<td class="author-text"><a href="mailto:[email protected]">[email protected]</a></td></tr>
<tr><td class="author" align="right">URI: </td>
<td class="author-text"><a href="http://josefsson.org/">http://josefsson.org/</a></td></tr>
</table>
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