File Coverage

blib/lib/Crypt/UnixCrypt.pm

Criterion	Covered	Total	%
statement	172	173	99.4
branch	15	18	83.3
condition	4	6	66.6
subroutine	16	16	100.0
pod	0	12	0.0
total	207	225	92.0

package Crypt::UnixCrypt;

use 5.004;  # i.e. not tested under earlier versions
use strict;
use vars qw($VERSION @ISA @EXPORT $OVERRIDE_BUILTIN);

$VERSION = '1.0';

require Exporter;
@ISA = qw(Exporter);

# Don't override built-in crypt() unless forced to to so
use Config;
@EXPORT = qw(crypt)
	if !defined $Config{d_crypt} ||
	   (defined $OVERRIDE_BUILTIN && $OVERRIDE_BUILTIN);


my $ITERATIONS = 16;

my @con_salt =
(
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
	0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
	0x0A, 0x0B, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A,
	0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x10, 0x11, 0x12,
	0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A,
	0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 0x21, 0x22,
	0x23, 0x24, 0x25, 0x20, 0x21, 0x22, 0x23, 0x24,
	0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C,
	0x2D, 0x2E, 0x2F, 0x30, 0x31, 0x32, 0x33, 0x34,
	0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C,
	0x3D, 0x3E, 0x3F, 0x00, 0x00, 0x00, 0x00, 0x00,
);

my @shifts2 =
(
	0, 0, 1, 1, 1, 1, 1, 1,
	0, 1, 1, 1, 1, 1, 1, 0
);

my @skb0 =
(
	# for C bits (numbered as per FIPS 46) 1 2 3 4 5 6
	0x00000000, 0x00000010, 0x20000000, 0x20000010,
	0x00010000, 0x00010010, 0x20010000, 0x20010010,
	0x00000800, 0x00000810, 0x20000800, 0x20000810,
	0x00010800, 0x00010810, 0x20010800, 0x20010810,
	0x00000020, 0x00000030, 0x20000020, 0x20000030,
	0x00010020, 0x00010030, 0x20010020, 0x20010030,
	0x00000820, 0x00000830, 0x20000820, 0x20000830,
	0x00010820, 0x00010830, 0x20010820, 0x20010830,
	0x00080000, 0x00080010, 0x20080000, 0x20080010,
	0x00090000, 0x00090010, 0x20090000, 0x20090010,
	0x00080800, 0x00080810, 0x20080800, 0x20080810,
	0x00090800, 0x00090810, 0x20090800, 0x20090810,
	0x00080020, 0x00080030, 0x20080020, 0x20080030,
	0x00090020, 0x00090030, 0x20090020, 0x20090030,
	0x00080820, 0x00080830, 0x20080820, 0x20080830,
	0x00090820, 0x00090830, 0x20090820, 0x20090830,
);
my @skb1 =
(
	# for C bits (numbered as per FIPS 46) 7 8 10 11 12 13
	0x00000000, 0x02000000, 0x00002000, 0x02002000,
	0x00200000, 0x02200000, 0x00202000, 0x02202000,
	0x00000004, 0x02000004, 0x00002004, 0x02002004,
	0x00200004, 0x02200004, 0x00202004, 0x02202004,
	0x00000400, 0x02000400, 0x00002400, 0x02002400,
	0x00200400, 0x02200400, 0x00202400, 0x02202400,
	0x00000404, 0x02000404, 0x00002404, 0x02002404,
	0x00200404, 0x02200404, 0x00202404, 0x02202404,
	0x10000000, 0x12000000, 0x10002000, 0x12002000,
	0x10200000, 0x12200000, 0x10202000, 0x12202000,
	0x10000004, 0x12000004, 0x10002004, 0x12002004,
	0x10200004, 0x12200004, 0x10202004, 0x12202004,
	0x10000400, 0x12000400, 0x10002400, 0x12002400,
	0x10200400, 0x12200400, 0x10202400, 0x12202400,
	0x10000404, 0x12000404, 0x10002404, 0x12002404,
	0x10200404, 0x12200404, 0x10202404, 0x12202404,
);
my @skb2 =
(
	# for C bits (numbered as per FIPS 46) 14 15 16 17 19 20
	0x00000000, 0x00000001, 0x00040000, 0x00040001,
	0x01000000, 0x01000001, 0x01040000, 0x01040001,
	0x00000002, 0x00000003, 0x00040002, 0x00040003,
	0x01000002, 0x01000003, 0x01040002, 0x01040003,
	0x00000200, 0x00000201, 0x00040200, 0x00040201,
	0x01000200, 0x01000201, 0x01040200, 0x01040201,
	0x00000202, 0x00000203, 0x00040202, 0x00040203,
	0x01000202, 0x01000203, 0x01040202, 0x01040203,
	0x08000000, 0x08000001, 0x08040000, 0x08040001,
	0x09000000, 0x09000001, 0x09040000, 0x09040001,
	0x08000002, 0x08000003, 0x08040002, 0x08040003,
	0x09000002, 0x09000003, 0x09040002, 0x09040003,
	0x08000200, 0x08000201, 0x08040200, 0x08040201,
	0x09000200, 0x09000201, 0x09040200, 0x09040201,
	0x08000202, 0x08000203, 0x08040202, 0x08040203,
	0x09000202, 0x09000203, 0x09040202, 0x09040203,
);
my @skb3 =
(
	# for C bits (numbered as per FIPS 46) 21 23 24 26 27 28
	0x00000000, 0x00100000, 0x00000100, 0x00100100,
	0x00000008, 0x00100008, 0x00000108, 0x00100108,
	0x00001000, 0x00101000, 0x00001100, 0x00101100,
	0x00001008, 0x00101008, 0x00001108, 0x00101108,
	0x04000000, 0x04100000, 0x04000100, 0x04100100,
	0x04000008, 0x04100008, 0x04000108, 0x04100108,
	0x04001000, 0x04101000, 0x04001100, 0x04101100,
	0x04001008, 0x04101008, 0x04001108, 0x04101108,
	0x00020000, 0x00120000, 0x00020100, 0x00120100,
	0x00020008, 0x00120008, 0x00020108, 0x00120108,
	0x00021000, 0x00121000, 0x00021100, 0x00121100,
	0x00021008, 0x00121008, 0x00021108, 0x00121108,
	0x04020000, 0x04120000, 0x04020100, 0x04120100,
	0x04020008, 0x04120008, 0x04020108, 0x04120108,
	0x04021000, 0x04121000, 0x04021100, 0x04121100,
	0x04021008, 0x04121008, 0x04021108, 0x04121108,
);
my @skb4 =
(
	# for D bits (numbered as per FIPS 46) 1 2 3 4 5 6
	0x00000000, 0x10000000, 0x00010000, 0x10010000,
	0x00000004, 0x10000004, 0x00010004, 0x10010004,
	0x20000000, 0x30000000, 0x20010000, 0x30010000,
	0x20000004, 0x30000004, 0x20010004, 0x30010004,
	0x00100000, 0x10100000, 0x00110000, 0x10110000,
	0x00100004, 0x10100004, 0x00110004, 0x10110004,
	0x20100000, 0x30100000, 0x20110000, 0x30110000,
	0x20100004, 0x30100004, 0x20110004, 0x30110004,
	0x00001000, 0x10001000, 0x00011000, 0x10011000,
	0x00001004, 0x10001004, 0x00011004, 0x10011004,
	0x20001000, 0x30001000, 0x20011000, 0x30011000,
	0x20001004, 0x30001004, 0x20011004, 0x30011004,
	0x00101000, 0x10101000, 0x00111000, 0x10111000,
	0x00101004, 0x10101004, 0x00111004, 0x10111004,
	0x20101000, 0x30101000, 0x20111000, 0x30111000,
	0x20101004, 0x30101004, 0x20111004, 0x30111004,
);
my @skb5 =
(
	# for D bits (numbered as per FIPS 46) 8 9 11 12 13 14
	0x00000000, 0x08000000, 0x00000008, 0x08000008,
	0x00000400, 0x08000400, 0x00000408, 0x08000408,
	0x00020000, 0x08020000, 0x00020008, 0x08020008,
	0x00020400, 0x08020400, 0x00020408, 0x08020408,
	0x00000001, 0x08000001, 0x00000009, 0x08000009,
	0x00000401, 0x08000401, 0x00000409, 0x08000409,
	0x00020001, 0x08020001, 0x00020009, 0x08020009,
	0x00020401, 0x08020401, 0x00020409, 0x08020409,
	0x02000000, 0x0A000000, 0x02000008, 0x0A000008,
	0x02000400, 0x0A000400, 0x02000408, 0x0A000408,
	0x02020000, 0x0A020000, 0x02020008, 0x0A020008,
	0x02020400, 0x0A020400, 0x02020408, 0x0A020408,
	0x02000001, 0x0A000001, 0x02000009, 0x0A000009,
	0x02000401, 0x0A000401, 0x02000409, 0x0A000409,
	0x02020001, 0x0A020001, 0x02020009, 0x0A020009,
	0x02020401, 0x0A020401, 0x02020409, 0x0A020409,
);
my @skb6 =
(
	# for D bits (numbered as per FIPS 46) 16 17 18 19 20 21
	0x00000000, 0x00000100, 0x00080000, 0x00080100,
	0x01000000, 0x01000100, 0x01080000, 0x01080100,
	0x00000010, 0x00000110, 0x00080010, 0x00080110,
	0x01000010, 0x01000110, 0x01080010, 0x01080110,
	0x00200000, 0x00200100, 0x00280000, 0x00280100,
	0x01200000, 0x01200100, 0x01280000, 0x01280100,
	0x00200010, 0x00200110, 0x00280010, 0x00280110,
	0x01200010, 0x01200110, 0x01280010, 0x01280110,
	0x00000200, 0x00000300, 0x00080200, 0x00080300,
	0x01000200, 0x01000300, 0x01080200, 0x01080300,
	0x00000210, 0x00000310, 0x00080210, 0x00080310,
	0x01000210, 0x01000310, 0x01080210, 0x01080310,
	0x00200200, 0x00200300, 0x00280200, 0x00280300,
	0x01200200, 0x01200300, 0x01280200, 0x01280300,
	0x00200210, 0x00200310, 0x00280210, 0x00280310,
	0x01200210, 0x01200310, 0x01280210, 0x01280310,
);
my @skb7 =
(
	# for D bits (numbered as per FIPS 46) 22 23 24 25 27 28
	0x00000000, 0x04000000, 0x00040000, 0x04040000,
	0x00000002, 0x04000002, 0x00040002, 0x04040002,
	0x00002000, 0x04002000, 0x00042000, 0x04042000,
	0x00002002, 0x04002002, 0x00042002, 0x04042002,
	0x00000020, 0x04000020, 0x00040020, 0x04040020,
	0x00000022, 0x04000022, 0x00040022, 0x04040022,
	0x00002020, 0x04002020, 0x00042020, 0x04042020,
	0x00002022, 0x04002022, 0x00042022, 0x04042022,
	0x00000800, 0x04000800, 0x00040800, 0x04040800,
	0x00000802, 0x04000802, 0x00040802, 0x04040802,
	0x00002800, 0x04002800, 0x00042800, 0x04042800,
	0x00002802, 0x04002802, 0x00042802, 0x04042802,
	0x00000820, 0x04000820, 0x00040820, 0x04040820,
	0x00000822, 0x04000822, 0x00040822, 0x04040822,
	0x00002820, 0x04002820, 0x00042820, 0x04042820,
	0x00002822, 0x04002822, 0x00042822, 0x04042822,
);

my @SPtrans0 =
(
	# nibble 0
	0x00820200, 0x00020000, 0x80800000, 0x80820200,
	0x00800000, 0x80020200, 0x80020000, 0x80800000,
	0x80020200, 0x00820200, 0x00820000, 0x80000200,
	0x80800200, 0x00800000, 0x00000000, 0x80020000,
	0x00020000, 0x80000000, 0x00800200, 0x00020200,
	0x80820200, 0x00820000, 0x80000200, 0x00800200,
	0x80000000, 0x00000200, 0x00020200, 0x80820000,
	0x00000200, 0x80800200, 0x80820000, 0x00000000,
	0x00000000, 0x80820200, 0x00800200, 0x80020000,
	0x00820200, 0x00020000, 0x80000200, 0x00800200,
	0x80820000, 0x00000200, 0x00020200, 0x80800000,
	0x80020200, 0x80000000, 0x80800000, 0x00820000,
	0x80820200, 0x00020200, 0x00820000, 0x80800200,
	0x00800000, 0x80000200, 0x80020000, 0x00000000,
	0x00020000, 0x00800000, 0x80800200, 0x00820200,
	0x80000000, 0x80820000, 0x00000200, 0x80020200,
);
my @SPtrans1 =
(
	# nibble 1
	0x10042004, 0x00000000, 0x00042000, 0x10040000,
	0x10000004, 0x00002004, 0x10002000, 0x00042000,
	0x00002000, 0x10040004, 0x00000004, 0x10002000,
	0x00040004, 0x10042000, 0x10040000, 0x00000004,
	0x00040000, 0x10002004, 0x10040004, 0x00002000,
	0x00042004, 0x10000000, 0x00000000, 0x00040004,
	0x10002004, 0x00042004, 0x10042000, 0x10000004,
	0x10000000, 0x00040000, 0x00002004, 0x10042004,
	0x00040004, 0x10042000, 0x10002000, 0x00042004,
	0x10042004, 0x00040004, 0x10000004, 0x00000000,
	0x10000000, 0x00002004, 0x00040000, 0x10040004,
	0x00002000, 0x10000000, 0x00042004, 0x10002004,
	0x10042000, 0x00002000, 0x00000000, 0x10000004,
	0x00000004, 0x10042004, 0x00042000, 0x10040000,
	0x10040004, 0x00040000, 0x00002004, 0x10002000,
	0x10002004, 0x00000004, 0x10040000, 0x00042000,
);
my @SPtrans2 =
(
	# nibble 2
	0x41000000, 0x01010040, 0x00000040, 0x41000040,
	0x40010000, 0x01000000, 0x41000040, 0x00010040,
	0x01000040, 0x00010000, 0x01010000, 0x40000000,
	0x41010040, 0x40000040, 0x40000000, 0x41010000,
	0x00000000, 0x40010000, 0x01010040, 0x00000040,
	0x40000040, 0x41010040, 0x00010000, 0x41000000,
	0x41010000, 0x01000040, 0x40010040, 0x01010000,
	0x00010040, 0x00000000, 0x01000000, 0x40010040,
	0x01010040, 0x00000040, 0x40000000, 0x00010000,
	0x40000040, 0x40010000, 0x01010000, 0x41000040,
	0x00000000, 0x01010040, 0x00010040, 0x41010000,
	0x40010000, 0x01000000, 0x41010040, 0x40000000,
	0x40010040, 0x41000000, 0x01000000, 0x41010040,
	0x00010000, 0x01000040, 0x41000040, 0x00010040,
	0x01000040, 0x00000000, 0x41010000, 0x40000040,
	0x41000000, 0x40010040, 0x00000040, 0x01010000,
);
my @SPtrans3 =
(
	# nibble 3
	0x00100402, 0x04000400, 0x00000002, 0x04100402,
	0x00000000, 0x04100000, 0x04000402, 0x00100002,
	0x04100400, 0x04000002, 0x04000000, 0x00000402,
	0x04000002, 0x00100402, 0x00100000, 0x04000000,
	0x04100002, 0x00100400, 0x00000400, 0x00000002,
	0x00100400, 0x04000402, 0x04100000, 0x00000400,
	0x00000402, 0x00000000, 0x00100002, 0x04100400,
	0x04000400, 0x04100002, 0x04100402, 0x00100000,
	0x04100002, 0x00000402, 0x00100000, 0x04000002,
	0x00100400, 0x04000400, 0x00000002, 0x04100000,
	0x04000402, 0x00000000, 0x00000400, 0x00100002,
	0x00000000, 0x04100002, 0x04100400, 0x00000400,
	0x04000000, 0x04100402, 0x00100402, 0x00100000,
	0x04100402, 0x00000002, 0x04000400, 0x00100402,
	0x00100002, 0x00100400, 0x04100000, 0x04000402,
	0x00000402, 0x04000000, 0x04000002, 0x04100400,
);
my @SPtrans4 =
(
	# nibble 4
	0x02000000, 0x00004000, 0x00000100, 0x02004108,
	0x02004008, 0x02000100, 0x00004108, 0x02004000,
	0x00004000, 0x00000008, 0x02000008, 0x00004100,
	0x02000108, 0x02004008, 0x02004100, 0x00000000,
	0x00004100, 0x02000000, 0x00004008, 0x00000108,
	0x02000100, 0x00004108, 0x00000000, 0x02000008,
	0x00000008, 0x02000108, 0x02004108, 0x00004008,
	0x02004000, 0x00000100, 0x00000108, 0x02004100,
	0x02004100, 0x02000108, 0x00004008, 0x02004000,
	0x00004000, 0x00000008, 0x02000008, 0x02000100,
	0x02000000, 0x00004100, 0x02004108, 0x00000000,
	0x00004108, 0x02000000, 0x00000100, 0x00004008,
	0x02000108, 0x00000100, 0x00000000, 0x02004108,
	0x02004008, 0x02004100, 0x00000108, 0x00004000,
	0x00004100, 0x02004008, 0x02000100, 0x00000108,
	0x00000008, 0x00004108, 0x02004000, 0x02000008,
);
my @SPtrans5 =
(
	# nibble 5
	0x20000010, 0x00080010, 0x00000000, 0x20080800,
	0x00080010, 0x00000800, 0x20000810, 0x00080000,
	0x00000810, 0x20080810, 0x00080800, 0x20000000,
	0x20000800, 0x20000010, 0x20080000, 0x00080810,
	0x00080000, 0x20000810, 0x20080010, 0x00000000,
	0x00000800, 0x00000010, 0x20080800, 0x20080010,
	0x20080810, 0x20080000, 0x20000000, 0x00000810,
	0x00000010, 0x00080800, 0x00080810, 0x20000800,
	0x00000810, 0x20000000, 0x20000800, 0x00080810,
	0x20080800, 0x00080010, 0x00000000, 0x20000800,
	0x20000000, 0x00000800, 0x20080010, 0x00080000,
	0x00080010, 0x20080810, 0x00080800, 0x00000010,
	0x20080810, 0x00080800, 0x00080000, 0x20000810,
	0x20000010, 0x20080000, 0x00080810, 0x00000000,
	0x00000800, 0x20000010, 0x20000810, 0x20080800,
	0x20080000, 0x00000810, 0x00000010, 0x20080010,
);
my @SPtrans6 =
(
	# nibble 6
	0x00001000, 0x00000080, 0x00400080, 0x00400001,
	0x00401081, 0x00001001, 0x00001080, 0x00000000,
	0x00400000, 0x00400081, 0x00000081, 0x00401000,
	0x00000001, 0x00401080, 0x00401000, 0x00000081,
	0x00400081, 0x00001000, 0x00001001, 0x00401081,
	0x00000000, 0x00400080, 0x00400001, 0x00001080,
	0x00401001, 0x00001081, 0x00401080, 0x00000001,
	0x00001081, 0x00401001, 0x00000080, 0x00400000,
	0x00001081, 0x00401000, 0x00401001, 0x00000081,
	0x00001000, 0x00000080, 0x00400000, 0x00401001,
	0x00400081, 0x00001081, 0x00001080, 0x00000000,
	0x00000080, 0x00400001, 0x00000001, 0x00400080,
	0x00000000, 0x00400081, 0x00400080, 0x00001080,
	0x00000081, 0x00001000, 0x00401081, 0x00400000,
	0x00401080, 0x00000001, 0x00001001, 0x00401081,
	0x00400001, 0x00401080, 0x00401000, 0x00001001,
);
my @SPtrans7 =
(
	# nibble 7
	0x08200020, 0x08208000, 0x00008020, 0x00000000,
	0x08008000, 0x00200020, 0x08200000, 0x08208020,
	0x00000020, 0x08000000, 0x00208000, 0x00008020,
	0x00208020, 0x08008020, 0x08000020, 0x08200000,
	0x00008000, 0x00208020, 0x00200020, 0x08008000,
	0x08208020, 0x08000020, 0x00000000, 0x00208000,
	0x08000000, 0x00200000, 0x08008020, 0x08200020,
	0x00200000, 0x00008000, 0x08208000, 0x00000020,
	0x00200000, 0x00008000, 0x08000020, 0x08208020,
	0x00008020, 0x08000000, 0x00000000, 0x00208000,
	0x08200020, 0x08008020, 0x08008000, 0x00200020,
	0x08208000, 0x00000020, 0x00200020, 0x08008000,
	0x08208020, 0x00200000, 0x08200000, 0x08000020,
	0x00208000, 0x00008020, 0x08008020, 0x08200000,
	0x00000020, 0x08208000, 0x00208020, 0x00000000,
	0x08000000, 0x08200020, 0x00008000, 0x00208020
);

my @cov_2char =
(
	0x2E, 0x2F, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35,
	0x36, 0x37, 0x38, 0x39, 0x41, 0x42, 0x43, 0x44,
	0x45, 0x46, 0x47, 0x48, 0x49, 0x4A, 0x4B, 0x4C,
	0x4D, 0x4E, 0x4F, 0x50, 0x51, 0x52, 0x53, 0x54,
	0x55, 0x56, 0x57, 0x58, 0x59, 0x5A, 0x61, 0x62,
	0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6A,
	0x6B, 0x6C, 0x6D, 0x6E, 0x6F, 0x70, 0x71, 0x72,
	0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A
);

sub ushr  # only for ints! (mimics the Java >>> operator)
{
	my ($n, $s) = @_;

	$s &= 0x1f;

	return( ($n >> $s) & (~0 >> $s) );
}

sub toByte
{
	my $value = shift;

	$value &= 0xff;
	$value = - ((~$value & 0xff) + 1)
		if $value & 0x80;

	return $value;
}

sub toInt
{
	my $value = shift;

	$value = - ((~$value & 0xffffffff) + 1)
		if $value & 0x80000000;

	return $value;
}

sub byteToUnsigned # int byteToUnsigned(byte b)
{
	my $value = shift;

	return( $value >= 0 ? $value : $value + 256 );
}

sub fourBytesToInt # int fourBytesToInt(byte b[], int offset)
{
	my ($b, $offset) = @_;
	my $value;

	$value  =  byteToUnsigned($b->[$offset++]);
	$value |= (byteToUnsigned($b->[$offset++]) <<  8);
	$value |= (byteToUnsigned($b->[$offset++]) << 16);
	$value |= (byteToUnsigned($b->[$offset++]) << 24);

	return toInt($value);
}

sub intToFourBytes # void intToFourBytes(int iValue, byte b[], int offset)
{
	my ($iValue, $b, $offset) = @_;

	$b->[$offset++] = toByte(ushr($iValue, 0) & 0xff);
	$b->[$offset++] = toByte(ushr($iValue, 8) & 0xff);
	$b->[$offset++] = toByte(ushr($iValue,16) & 0xff);
	$b->[$offset++] = toByte(ushr($iValue,24) & 0xff);

	return undef;
}

sub PERM_OP # void PERM_OP(int a, int b, int n, int m, int results[])
{
	my ($a, $b, $n, $m, $results) = @_;
	my $t;

	$t = (ushr($a,$n) ^ $b) & $m;
	$a ^= $t << $n;
	$b ^= $t;

	$results->[0] = toInt($a);
	$results->[1] = toInt($b);

	return undef;
}

sub HPERM_OP # void HPERM_OP(int a, int n, int m)
{
	my ($a, $n, $m) = @_;
	my $t;

	$t = (($a << (16 - $n)) ^ $a) & $m;
	$a = $a ^ $t ^ ushr($t, 16 - $n);

	return toInt($a);
}

sub des_set_key # int [] des_set_key(byte key[])
{
	my ($key) = @_;
	my @schedule; $#schedule = $ITERATIONS * 2 -1;

	my $c = fourBytesToInt($key, 0);
	my $d = fourBytesToInt($key, 4);

	my @results; $#results = 1;

	PERM_OP($d, $c, 4, 0x0f0f0f0f, \@results);
	$d = $results[0]; $c = $results[1];

	$c = HPERM_OP($c, -2, 0xcccc0000);
	$d = HPERM_OP($d, -2, 0xcccc0000);

	PERM_OP($d, $c, 1, 0x55555555, \@results);
	$d = $results[0]; $c = $results[1];

	PERM_OP($c, $d, 8, 0x00ff00ff, \@results);
	$c = $results[0]; $d = $results[1];

	PERM_OP($d, $c, 1, 0x55555555, \@results);
	$d = $results[0]; $c = $results[1];

	$d = (    (($d & 0x000000ff) << 16) |     ($d & 0x0000ff00)  |
	       ushr($d & 0x00ff0000,    16) | ushr($c & 0xf0000000, 4));
	$c &= 0x0fffffff;

	my ($s, $t);
	my ($i, $j);

	$j = 0;
	for($i = 0; $i < $ITERATIONS; $i++)
	{
		if($shifts2[$i])
		{
			$c = ushr($c, 2) | ($c << 26);
			$d = ushr($d, 2) | ($d << 26);
		}
		else
		{
			$c = ushr($c, 1) | ($c << 27);
			$d = ushr($d, 1) | ($d << 27);
		}

		$c &= 0x0fffffff;
		$d &= 0x0fffffff;

		$s = $skb0[     ($c   ) & 0x3f                        ]|
		     $skb1[(ushr($c, 6) & 0x03) | (ushr($c, 7) & 0x3c)]|
		     $skb2[(ushr($c,13) & 0x0f) | (ushr($c,14) & 0x30)]|
		     $skb3[(ushr($c,20) & 0x01) | (ushr($c,21) & 0x06) |
		                                  (ushr($c,22) & 0x38)];

		$t = $skb4[     ($d   ) & 0x3f                         ]|
		     $skb5[(ushr($d, 7) & 0x03) | (ushr($d, 8) & 0x3c) ]|
		     $skb6[ ushr($d,15) & 0x3f                         ]|
		     $skb7[(ushr($d,21) & 0x0f) | (ushr($d,22) & 0x30)];

		$schedule[$j++] = (    ($t << 16) | ($s & 0x0000ffff)) & 0xffffffff;
		$s              = (ushr($s,   16) | ($t & 0xffff0000));

		$s              = ($s << 4) | ushr($s,28);
		$schedule[$j++] = $s & 0xffffffff;
	}

	return \@schedule;
}

sub D_ENCRYPT # int D_ENCRYPT(int L, int R, int S, int E0, int E1, int s[])
{
	my ($L, $R, $S, $E0, $E1, $s) = @_;
	my ($t, $u, $v);

	$v = $R ^ ushr($R,16);
	$u = $v & $E0;
	$v = $v & $E1;
	$u = ($u ^ ($u << 16)) ^ $R ^ $s->[$S];
	$t = ($v ^ ($v << 16)) ^ $R ^ $s->[$S + 1];
	$t = ushr($t, 4) | ($t << 28);

	$L ^= $SPtrans1[    ($t    ) & 0x3f] |
	      $SPtrans3[ushr($t,  8) & 0x3f] |
	      $SPtrans5[ushr($t, 16) & 0x3f] |
	      $SPtrans7[ushr($t, 24) & 0x3f] |
	      $SPtrans0[    ($u    ) & 0x3f] |
	      $SPtrans2[ushr($u,  8) & 0x3f] |
	      $SPtrans4[ushr($u, 16) & 0x3f] |
	      $SPtrans6[ushr($u, 24) & 0x3f];

	return $L;
}

sub body # int [] body(int schedule[], int Eswap0, int Eswap1)
{
	my ($schedule, $Eswap0, $Eswap1) = @_;
	my $left  = 0;
	my $right = 0;
	my $t     = 0;

	my ($i, $j);
	for($j = 0; $j < 25; $j++)
	{
		for($i = 0; $i < $ITERATIONS * 2; $i += 4)
		{
			$left  = D_ENCRYPT($left,  $right, $i,     $Eswap0, $Eswap1, $schedule);
			$right = D_ENCRYPT($right, $left,  $i + 2, $Eswap0, $Eswap1, $schedule);
		}
		$t     = $left;
		$left  = $right;
		$right = $t;
	}

	$t = $right;

	$right = ushr($left, 1) | ($left << 31);
	$left  = ushr($t   , 1) | ($t    << 31);

	$left  &= 0xffffffff;
	$right &= 0xffffffff;

	my @results; $#results = 1;

	PERM_OP($right, $left, 1, 0x55555555, \@results);
	$right = $results[0]; $left = $results[1];

	PERM_OP($left, $right, 8, 0x00ff00ff, \@results);
	$left = $results[0]; $right = $results[1];

	PERM_OP($right, $left, 2, 0x33333333, \@results);
	$right = $results[0]; $left = $results[1];

	PERM_OP($left, $right, 16, 0x0000ffff, \@results);
	$left = $results[0]; $right = $results[1];

	PERM_OP($right, $left, 4, 0x0f0f0f0f, \@results);
	$right = $results[0]; $left = $results[1];

	my @out; $#out = 1;

	$out[0] = $left; $out[1] = $right;

	return \@out;
}

sub crypt($$) # String crypt(String plaintext, String salt)
{
	my ($plaintext, $salt) = @_;
	my $buffer = '';

	return $buffer if !defined $salt || $salt eq '';

	$salt .= $salt if length $salt < 2;
	$plaintext = '' if !defined $plaintext;

	$buffer = substr $salt,0,2;

	my $Eswap0 = $con_salt[ord(substr $salt,0,1)];
	my $Eswap1 = $con_salt[ord(substr $salt,1,1)] << 4;

	my @key;
	@key[0..7] = (0) x 8;

	my @iChar = map { ord($_) << 1 } split(//, $plaintext);
	my $i;
	for (my $i = 0; $i < @key && $i < @iChar; $i++) {
		$key[$i] = toByte($iChar[$i]);
	}

	my $schedule = des_set_key(\@key);
	my $out      = body($schedule, $Eswap0, $Eswap1);

	my @b; $#b = 8;

	intToFourBytes($out->[0], \@b, 0);
	intToFourBytes($out->[1], \@b, 4);
	$b[8] = 0;

	my ($j, $c, $y, $u);
	for($i = 2, $y = 0, $u = 0x80; $i < 13; $i++)
	{
		for($j = 0, $c = 0; $j < 6; $j++)
		{
			$c <<= 1;

			$c |= 1 if ($b[$y] & $u) != 0;

			$u >>= 1;

			if($u == 0)
			{
				$y++;
				$u = 0x80;
			}
		}
		$buffer .= chr($cov_2char[$c]);
	}

	return $buffer;
}

1;
__END__