Terms & Definitions

An xor-rotate and fold operation uses an internal buffer of 20 octets, initialized with zeros. It processes input, 20 octets at a time. If the input length is not a multiple of 20 octets, then that input data is padded with zeros until it is a multiple of 20 octets.

Every time the operation receives another 20 octets of input, the internal buffer is circular left rotated by 1 bit, and the 20 octets of input is then xor-ed into the internal buffer.

When the input has been exhausted, the internal buffer is returned as output.