Adding Support for Salted Password Databases to EAP-pwd
RFC 8146
Document | Type |
RFC - Informational
(April 2017; Errata)
Updates RFC 5931
Was draft-harkins-salted-eap-pwd (individual)
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Author | Dan Harkins | ||
Last updated | 2020-01-21 | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized with errata bibtex | ||
Reviews | |||
Stream | WG state | (None) | |
Document shepherd | Stefan Winter | ||
Shepherd write-up | Show (last changed 2016-08-24) | ||
IESG | IESG state | RFC 8146 (Informational) | |
Consensus Boilerplate | Yes | ||
Telechat date | |||
Responsible AD | Kathleen Moriarty | ||
Send notices to | "Stefan Winter" <stefan.winter@restena.lu>, dharkins@arubanetworks.com | ||
IANA | IANA review state | Version Changed - Review Needed | |
IANA action state | RFC-Ed-Ack |
Internet Engineering Task Force (IETF) D. Harkins Request for Comments: 8146 HP Enterprise Updates: 5931 April 2017 Category: Informational ISSN: 2070-1721 Adding Support for Salted Password Databases to EAP-pwd Abstract EAP-pwd is an Extensible Authentication Protocol (EAP) method that utilizes a shared password for authentication using a technique that is resistant to dictionary attacks. It includes support for raw keys and double hashing of a password in the style of Microsoft Challenge Handshake Authentication Protocol version 2 (MSCHAPv2), but it does not include support for salted passwords. There are many existing databases of salted passwords, and it is desirable to allow their use with EAP-pwd. Status of This Memo This document is not an Internet Standards Track specification; it is published for informational purposes. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Not all documents approved by the IESG are a candidate for any level of Internet Standard; see Section 2 of RFC 7841. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc8146. Harkins Informational [Page 1] RFC 8146 NaCled EAP-pwd April 2017 Copyright Notice Copyright (c) 2017 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 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. Table of Contents 1. Introduction ....................................................3 1.1. Background .................................................3 1.2. Keyword Definition .........................................3 2. Salted Passwords in EAP-pwd .....................................3 2.1. Password Preprocessing .....................................3 2.2. The Salting of a Password ..................................5 2.3. Using UNIX crypt ...........................................5 2.4. Using scrypt ...............................................6 2.5. Using PBKDF2 ...............................................6 2.6. Protocol Modifications .....................................7 2.7. Payload Modifications ......................................8 3. IANA Considerations .............................................8 4. Security Considerations .........................................9 5. References ......................................................9 5.1. Normative References .......................................9 5.2. Informative References ....................................10 Acknowledgements ..................................................11 Author's Address ..................................................11 Harkins Informational [Page 2] RFC 8146 NaCled EAP-pwd April 2017 1. Introduction 1.1. Background Databases of stored passwords present an attractive target for attack -- get access to the database, learn the passwords. To confound such attacks, a random "salt" was hashed with the password and the resulting digest stored, along with the salt, instead of the raw password. This has the effect of randomizing the password; even if two, distinct users have chosen the same password, the stored, and salted, password will be different. It also requires an adversary who has compromised the security of the stored database to launch a dictionary attack per entry to recover passwords. Dictionary attacks, especially using custom hardware, represent real- world attacks and merely salting a password is insufficient to protect a password database. To address these attacks, a sequential memory hard function, such as described in [RFC7914], is used. While salting a password database is not sufficient to deal with many real-world attacks, the historic popularity of password salting means there are a large number of such databases deployed, and EAP-pwdShow full document text