RFC 2831 (rfc2831) - Page 1 of 27
Using Digest Authentication as a SASL Mechanism
Alternative Format: Original Text Document
Network Working Group P. Leach
Request for Comments: 2831 Microsoft
Category: Standards Track C. Newman
Innosoft
May 2000
Using Digest Authentication as a SASL Mechanism
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2000). All Rights Reserved.
Abstract
This specification defines how HTTP Digest Authentication [Digest]
can be used as a SASL [RFC 2222] mechanism for any protocol that has
a SASL profile. It is intended both as an improvement over CRAM-MD5
[RFC 2195] and as a convenient way to support a single authentication
mechanism for web, mail, LDAP, and other protocols.
Table of Contents
1 INTRODUCTION.....................................................2
1.1 CONVENTIONS AND NOTATION......................................2
1.2 REQUIREMENTS..................................................3
2 AUTHENTICATION...................................................3
2.1 INITIAL AUTHENTICATION........................................3
2.1.1 Step One...................................................3
2.1.2 Step Two...................................................6
2.1.3 Step Three................................................12
2.2 SUBSEQUENT AUTHENTICATION....................................12
2.2.1 Step one..................................................13
2.2.2 Step Two..................................................13
2.3 INTEGRITY PROTECTION.........................................13
2.4 CONFIDENTIALITY PROTECTION...................................14
3 SECURITY CONSIDERATIONS.........................................15
3.1 AUTHENTICATION OF CLIENTS USING DIGEST AUTHENTICATION........15
3.2 COMPARISON OF DIGEST WITH PLAINTEXT PASSWORDS................16
3.3 REPLAY ATTACKS...............................................16
Leach & Newman Standards Track