The scrypt Password-Based Key Derivation Function (RFC7914)
Original Publication Date: 2016-Aug-01
Included in the Prior Art Database: 2016-Aug-18
Internet Society Requests For Comment (RFCs)
C. Percival: AUTHOR [+2]
Password-based key derivation functions are used in cryptography and security protocols for deriving one or more secret keys from a secret value. Over the years, several password-based key derivation functions have been used, including the original DES-based UNIX Crypt-function, FreeBSD MD5 crypt, Public-Key Cryptography Standards#5 (PKCS#5) PBKDF2 [RFC2898] (typically used with SHA-1), GNU SHA-256/512 crypt [SHA2CRYPT], Windows NT LAN Manager (NTLM) [NTLM] hash, and the Blowfish-based bcrypt [BCRYPT]. These algorithms are all based on a cryptographic primitive combined with salting and/or iteration. The iteration count is used to slow down the computation, and the salt is used to make pre-computation costlier.
Internet Engineering Task Force (IETF) C. Percival Request for Comments: 7914 Tarsnap Category: Informational S. Josefsson ISSN: 2070-1721 SJD AB August 2016
The scrypt Password-Based Key Derivation Function
This document specifies the password-based key derivation function scrypt. The function derives one or more secret keys from a secret string. It is based on memory-hard functions, which offer added protection against attacks using custom hardware. The document also provides an ASN.1 schema.
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/rfc7914.
Copyright (c) 2016 IETF Trust and the persons identified as the document authors. All rights reserved.
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Percival & Josefsson Informational [Page 1]
RFC 7914 scrypt PBKDF August 2016
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. scrypt Parameters . . . . . . . . . . . . . . . . . . . . . . 3
3. The Salsa20/8 Core Function . . . . . . . . . . . . . . . . . 4
4. The scryptBlockMix Algorithm . . . . . . . . . . . . . . . . 5
5. The scrypt...