RFC 4418 · INFORMATIONAL · 2006

UMAC: Message Authentication Code using Universal Hashing

Overview

RFC 4418, “UMAC: Message Authentication Code using Universal Hashing”, is an Informational document published in March 2006 by T. Krovetz. The canonical text is published by the RFC Editor.

Abstract

This specification describes how to generate an authentication tag using the UMAC message authentication algorithm. UMAC is designed to be very fast to compute in software on contemporary uniprocessors. Measured speeds are as low as one cycle per byte. UMAC relies on addition of 32-bit and 64-bit numbers and multiplication of 32-bit numbers, operations well-supported by contemporary machines.

To generate the authentication tag on a given message, a "universal" hash function is applied to the message and key to produce a short, fixed-length hash value, and this hash value is then xor'ed with a key-derived pseudorandom pad. UMAC enjoys a rigorous security analysis, and its only internal "cryptographic" component is a block cipher used to generate the pseudorandom pads and internal key material. 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 4418 is hosted at rfc-editor.org. Available in TXT,HTML.

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