US Secure Hash Algorithm 1 (SHA1)

The purpose of this document is to make the SHA-1 (Secure Hash Algorithm 1) hash algorithm conveniently available to the Internet community.The United States of America has adopted the SHA-1 hash algorithm described herein as a Federal Information Processing Standard.Most of the text herein was taken by the authors from FIPS 180-1.Only the C code implementation is "original". AcknowledgementsMost of the text herein was taken from [FIPS 180-1].Only the C code implementation is "original" but its style is similar to the previously published MD4 and MD5 RFCs [RFCs 1320, 1321].The SHA-1 is based on principles similar to those used by Professor Ronald L. Rivest of MIT when designing the MD4 message digest algorithm [MD4] and is modeled after that algorithm [RFC 1320].