The SHA1 core from Alma Technologies is a high performance implementation of the SHA-1 (Secure Hash Algorithm 1) one-way cryptographic hash function, compliant with FIPS 180-1. The core is composed of two main units, the SHA1 Engine and the Padding Unit. The SHA1 Engine applies the SHA1 loops on a single 512-bit message block, while the Padding Unit splits the input message into 512-bit blocks and performs the message padding on the last block of the message.
The processing of one 512-bit block is performed in 82 clock cycles and the bit-rate achieved is 6.24Mbps / MHz on the input of the SHA1 core.
The SHA1 core is equipped with easy-to-use fully stallable interfaces both for input and output. These are designed to permit the user’s application to stop the data stream from the core when it is not able to receive data or to stop the input stream towards the core according to data arrival rate.