Philip Withnall authored Jan 08, 2014 and Olivier Crête committed Jan 31, 2014

Rather than using an intermediate method which takes a vector of
buffers, just use the SHA1 iteration functions directly in the HMAC
calculations. This eliminates several cases where the vector of buffers
was of fixed length, and it was actually taking more code to set up and
pass the vector than it would have to call the iteration functions
directly.