sha1_transform

The SHA-1 compression function over one 64-byte block, from the standard initial state: the 20-byte result, with no padding and no length.

A block shorter than 64 bytes is padded with zero bytes; bytes past the 64th are not used. This is the function G of FIPS 186-2’s random-number generator, not a digest of the data.

Synopsis

use Digest::SHA1 qw(sha1_transform);
my $g = sha1_transform($xkey);