MAKEKEY(1)MAKEKEY(1)NAME
makekey - generate encryption key
SYNOPSIS
/usr/lib/makekey
DESCRIPTION
makekey improves the usefulness of encryption schemes that depend on a
key by increasing the amount of time required to search the key space.
It attempts to read 8 bytes for its key (the first eight input bytes),
then it attempts to read 2 bytes for its salt (the last two input
bytes). The output depends on the input in a way intended to be diffi‐
cult to compute (that is, to require a substantial fraction of a sec‐
ond).
The first eight input bytes (the input key) can be arbitrary ASCII
characters. The last two (the salt) are best chosen from the set of
digits, ., /, upper- and lower-case letters. The salt characters are
repeated as the first two characters of the output. The remaining 11
output characters are chosen from the same set as the salt and consti‐
tute the output key.
The transformation performed is essentially the following: the salt is
used to select one of 4,096 cryptographic machines all based on the
National Bureau of Standards DES algorithm, but broken in 4,096 differ‐
ent ways. Using the input key as key, a constant string is fed into
the machine and recirculated a number of times. The 64 bits that come
out are distributed into the 66 output key bits in the result.
makekey is intended for programs that perform encryption. Usually, its
input and output will be pipes.
SEE ALSOed(1), vi(1), passwd(4)NOTES
makekey can produce different results depending upon whether the input
is typed at the terminal or redirected from a file.
Mar 3, 2008 MAKEKEY(1)