[unix-history] / .ref-BSD-3 / usr / man / man8 / makekey.8

.TH MAKEKEY 8 
.SH NAME
makekey \- generate encryption key
.SH SYNOPSIS
.B /usr/lib/makekey
.SH DESCRIPTION
.I Makekey
improves the usefulness of encryption schemes
depending on a key by increasing the amount of time required to
search the key space.
It reads 10 bytes from its standard input,
and writes 13 bytes on its standard output.
The output depends on the input in a way intended
to be difficult to compute (i.e. to require a substantial
fraction of a second).
.PP
The first eight input bytes
(the
.IR "input key" )
can be arbitrary ASCII characters.
The last 
two (the
.IR salt )
are best chosen from the set of digits, upper- and lower-case
letters, and `.' and `/'.
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 constitute the
.I "output key."
.PP
The transformation performed is essentially the following:
the salt is used to select one of 4096 cryptographic
machines all based on the National Bureau of Standards
DES algorithm, but modified in 4096 different 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 useful key bits in the result.
.PP
.I Makekey
is intended for programs that perform encryption
(e.g.
.I ed
and
.IR crypt (1)).
Usually its input and output will be pipes.
.SH SEE ALSO
crypt(1), ed(1)
Commit	Line	Data
e6817382 BJ	1	.TH MAKEKEY 8
	2	.SH NAME
	3	makekey \- generate encryption key
	4	.SH SYNOPSIS
	5	.B /usr/lib/makekey
	6	.SH DESCRIPTION
	7	.I Makekey
	8	improves the usefulness of encryption schemes
	9	depending on a key by increasing the amount of time required to
	10	search the key space.
	11	It reads 10 bytes from its standard input,
	12	and writes 13 bytes on its standard output.
	13	The output depends on the input in a way intended
	14	to be difficult to compute (i.e. to require a substantial
	15	fraction of a second).
	16	.PP
	17	The first eight input bytes
	18	(the
	19	.IR "input key" )
	20	can be arbitrary ASCII characters.
	21	The last
	22	two (the
	23	.IR salt )
	24	are best chosen from the set of digits, upper- and lower-case
	25	letters, and `.' and `/'.
	26	The salt characters are repeated as the first two characters of the output.
	27	The remaining 11 output characters are chosen from the same set as the salt
	28	and constitute the
	29	.I "output key."
	30	.PP
	31	The transformation performed is essentially the following:
	32	the salt is used to select one of 4096 cryptographic
	33	machines all based on the National Bureau of Standards
	34	DES algorithm, but modified in 4096 different ways.
	35	Using the input key as key,
	36	a constant string is fed into the machine and recirculated
	37	a number of times.
	38	The 64 bits that come out are distributed into the
	39	66 useful key bits in the result.
	40	.PP
	41	.I Makekey
	42	is intended for programs that perform encryption
	43	(e.g.
	44	.I ed
	45	and
	46	.IR crypt (1)).
	47	Usually its input and output will be pipes.
	48	.SH SEE ALSO
	49	crypt(1), ed(1)