SLUUCP8 June 2024 BQ41Z50
SHA-128 (SHA-1) and SHA-256 (SHA-2) auhentications are both base on secure hash algorithm described in FIPS 180-4 to compute a condensed representation of a message or data also known as hash. For messages < 264, the algorithm produces a 160-bit output called a digest.
In a SHA one-way hash function, there is no known mathematical method of computing the input given, only the output. The specification of SHA, as defined by FIPS 180-4, states that the input consists of 512-bit blocks with a total input length less than 264 bits. Inputs that do not conform to integer multiples of 512-bit blocks are padded before any block is input to the hash function. The SHA algorithm outputs the 160-bit digest.
The BQ41Z50 device generates a SHA-1 input block of 288 bits (160-bit message + 128-bit key) or a SHA-2 input block of 416 bits ( 160-bit message + 256-bit key) . The device pads the key and messages according to the pad requirements specified by FIPS 180-4.
Detailed information about the SHA algorithm can be found here: