.TH MAKEKEY 8 .SH NAMEmakekey \- generate encryption key.SH SYNOPSIS.B /usr/lib/makekey.SH DESCRIPTION.I Makekeyimproves the usefulness of encryption schemesdepending on a key by increasing the amount of time required tosearch 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 intendedto be difficult to compute (i.e. to require a substantialfraction of a second)..PPThe 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-caseletters, 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 saltand constitute the.I "output key.".PPThe transformation performed is essentially the following:the salt is used to select one of 4096 cryptographicmachines all based on the National Bureau of StandardsDES algorithm, but modified in 4096 different ways.Using the input key as key,a constant string is fed into the machine and recirculateda number of times.The 64 bits that come out are distributed into the66 useful key bits in the result..PP.I Makekeyis intended for programs that perform encryption(e.g..I edand.IR crypt (1)).Usually its input and output will be pipes..SH SEE ALSOcrypt(1), ed(1)