Definition (from RFC 2104)
- HMAC (K,m) = H ((K ⊕ opad) ∥ H ((K ⊕ ipad) ∥ m))
where
- H is a cryptographic hash function,
- K is a secret key padded to the right with extra zeros to the input block size of the hash function, or the hash of the original key if it's longer than that block size,
- m is the message to be authenticated,
- ∥ denotes concatenation,
- ⊕ denotes exclusive or (XOR),
- opad is the outer padding (0x5c5c5c…5c5c, one-block-long hexadecimal constant),
- and ipad is the inner padding (0x363636…3636, one-block-long hexadecimal constant).
Read more about this topic: Hash-based Message Authentication Code
Famous quotes containing the word definition:
“According to our social pyramid, all men who feel displaced racially, culturally, and/or because of economic hardships will turn on those whom they feel they can order and humiliate, usually women, children, and animals—just as they have been ordered and humiliated by those privileged few who are in power. However, this definition does not explain why there are privileged men who behave this way toward women.”
—Ana Castillo (b. 1953)
Related Phrases
Related Words