55.1 Description
The Secure Hash Algorithm (SHA) is compliant with the American FIPS (Federal Information Processing Standard) Publication 180-4 specification.
The 512/1024-bit block of message is respectively stored in 16/32 x 32-bit registers, (SHA_IDATARx/SHA_IODATARx) which are write-only.
As soon as the input data is written, hash processing can be started. The registers comprising the block of a message must be entered consecutively. Then, after the processing period, the message digest is ready to be read out on the 5 up to 8/16 x 32-bit output data registers (SHA_IODATARx) or through the DMA channels.
The SHA supports the SHA512 derivative algorithms SHA512/224 and SHA512/256 which are based on the SHA512 algorithm with specific initial vectors and a truncated digest. Unless specified otherwise, features and functionality of the SHA512 algorithm also apply to the SHA512/224 and SHA512/256 algorithms.
The SHA supports the HMAC-SHA512 derivative algorithms HMAC-SHA512/224 and HMAC-SHA512/256 which are based on the HMAC-SHA512 algorithm with specific initial vectors and a truncated digest. Unless specified otherwise, features and functionality of the HMAC-SHA512 algorithm also apply to the HMAC-SHA512/224 and HMAC-SHA512/256 algorithms.