RFC 4634 · INFORMATIONAL · 2006

US Secure Hash Algorithms

Overview

RFC 4634, “US Secure Hash Algorithms”, is an Informational document published in August 2006 by D. Eastlake 3rd, T. Hansen. It updates RFC 3174. It has been obsoleted by RFC 6234 — refer to the newer document for the authoritative version. The canonical text is published by the RFC Editor.

Abstract

The United States of America has adopted a suite of Secure Hash Algorithms (SHAs), including four beyond SHA-1, as part of a Federal Information Processing Standard (FIPS), specifically SHA-224 (RFC 3874), SHA-256, SHA-384, and SHA-512. The purpose of this document is to make source code performing these hash functions conveniently available to the Internet community. The sample code supports input strings of arbitrary bit length. SHA-1's sample code from RFC 3174 has also been updated to handle input strings of arbitrary bit length. Most of the text herein was adapted by the authors from FIPS 180-2.

Code to perform SHA-based HMACs, with arbitrary bit length text, is also included. This memo provides information for the Internet community.

Abstract as published in the RFC, via rfc-editor.org.

What “Informational” means

Published for the general information of the community. It does not define an IETF standard and carries no standards-track status.

Read this RFC

The canonical text of RFC 4634 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
Obsoleted by
RFC 6234
This RFC updates
RFC 3174
Other RFCs from 2006

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