factor/extra/crypto/passwd-md5/passwd-md5.factor

48 lines
1.7 KiB
Factor

! Copyright (C) 2008 Doug Coleman.
! See http://factorcode.org/license.txt for BSD license.
USING: kernel base64 checksums.md5 sequences checksums
locals prettyprint math math.bits grouping io combinators
fry make combinators.short-circuit math.functions splitting ;
IN: crypto.passwd-md5
<PRIVATE
: lookup-table ( n -- nth )
"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz" nth ; inline
: to64 ( v n -- string )
[ [ -6 shift ] [ 6 2^ 1- bitand lookup-table ] bi ]
replicate nip ; inline
PRIVATE>
:: passwd-md5 ( magic salt password -- bytes )
[let* | final! [ password magic salt 3append
salt password tuck 3append md5 checksum-bytes
password length
[ 16 / ceiling swap <repetition> concat ] keep
head-slice append
password [ length make-bits ] [ first ] bi
'[ CHAR: \0 _ ? ] "" map-as append
md5 checksum-bytes ] |
1000 [
"" swap
{
[ 0 bit? password final ? append ]
[ 3 mod 0 > [ salt append ] when ]
[ 7 mod 0 > [ password append ] when ]
[ 0 bit? final password ? append ]
} cleave md5 checksum-bytes final!
] each
magic salt "$" 3append
{ 12 0 6 13 1 7 14 2 8 15 3 9 5 4 10 } final nths 3 group
[ first3 [ 16 shift ] [ 8 shift ] bi* + + 4 to64 ] map concat
11 final nth 2 to64 3append ] ;
: parse-shadow-password ( string -- magic salt password )
"$" split harvest first3 [ "$" tuck 3append ] 2dip ;
: authenticate-password ( shadow password -- ? )
'[ parse-shadow-password drop _ passwd-md5 ] keep = ;