QuickHash Library

HMAC Overview

Providing a way to check the integrity of information transmitted over or stored in an unreliable medium is a prime necessity in the world of open computing and communications. Mechanisms that provide such integrity check based on a secret key are usually called  "Message Authentication Codes" (MACs). Typically, message authentication codes are used between two parties that share a secret key in order to validate information transmitted between these parties.

MACs based on cryptographic hash functions are known as "Keyed-Hash Message Authentication Codes" (HMACs).

HMAC, as defined in RFC2104, is a mechanism for message authentication using cryptographic hash functions. HMAC can be used with any iterative cryptographic hash function, e.g., MD5, SHA-1, in combination with a secret shared key.  The cryptographic strength of HMAC depends on the properties of the underlying hash function.

CHMAC Overview   |   HMAC API Overview   |   Type Library Overview   |   Useful Links   |   HashCalc

See Also    QuickHash Library Overview