#! /usr/bin/env perl

# Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.

#

# Licensed under the OpenSSL license (the "License").  You may not use

# this file except in compliance with the License.  You can obtain a copy

# in the file LICENSE in the source distribution or at

# https://www.openssl.org/source/license.html

# This flag makes the inner loop one cycle longer, but generates

# code that runs %30 faster on the pentium pro/II, 44% faster

# of PIII, while only %7 slower on the pentium.

# By default, this flag is on.

$ppro=1;

$0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1;

push(@INC,"${dir}","${dir}../../perlasm");

require "x86asm.pl";

require "cbc.pl";

$output=pop;

open STDOUT,">$output";

&asm_init($ARGV[0],$ARGV[$#ARGV] eq "386");

$CAST_ROUNDS=16;

$L="edi";

$R="esi";

$K="ebp";

$tmp1="ecx";

$tmp2="ebx";

$tmp3="eax";

$tmp4="edx";

$S1="CAST_S_table0";

$S2="CAST_S_table1";

$S3="CAST_S_table2";

$S4="CAST_S_table3";

@F1=("add","xor","sub");

@F2=("xor","sub","add");

@F3=("sub","add","xor");

&CAST_encrypt("CAST_encrypt",1);

&CAST_encrypt("CAST_decrypt",0);

&cbc("CAST_cbc_encrypt","CAST_encrypt","CAST_decrypt",1,4,5,3,-1,-1);

&asm_finish();

close STDOUT or die "error closing STDOUT: $!";

sub CAST_encrypt {

    local($name,$enc)=@_;

    local($win_ex)=<<"EOF";

EXTERN	_CAST_S_table0:DWORD

EXTERN	_CAST_S_table1:DWORD

EXTERN	_CAST_S_table2:DWORD

EXTERN	_CAST_S_table3:DWORD

EOF

    &main::external_label(

			  "CAST_S_table0",

			  "CAST_S_table1",

			  "CAST_S_table2",

			  "CAST_S_table3",

			  );

    &function_begin_B($name,$win_ex);

    &comment("");

    &push("ebp");

    &push("ebx");

    &mov($tmp2,&wparam(0));

    &mov($K,&wparam(1));

    &push("esi");

    &push("edi");

    &comment("Load the 2 words");

    &mov($L,&DWP(0,$tmp2,"",0));

    &mov($R,&DWP(4,$tmp2,"",0));

    &comment('Get short key flag');

    &mov($tmp3,&DWP(128,$K,"",0));

    if($enc) {

	&push($tmp3);

    } else {

	&or($tmp3,$tmp3);

	&jnz(&label('cast_dec_skip'));

    }

    &xor($tmp3,	$tmp3);

    # encrypting part

    if ($enc) {

	&E_CAST( 0,$S,$L,$R,$K,@F1,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 1,$S,$R,$L,$K,@F2,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 2,$S,$L,$R,$K,@F3,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 3,$S,$R,$L,$K,@F1,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 4,$S,$L,$R,$K,@F2,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 5,$S,$R,$L,$K,@F3,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 6,$S,$L,$R,$K,@F1,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 7,$S,$R,$L,$K,@F2,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 8,$S,$L,$R,$K,@F3,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 9,$S,$R,$L,$K,@F1,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST(10,$S,$L,$R,$K,@F2,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST(11,$S,$R,$L,$K,@F3,$tmp1,$tmp2,$tmp3,$tmp4);

	&comment('test short key flag');

	&pop($tmp4);

	&or($tmp4,$tmp4);

	&jnz(&label('cast_enc_done'));

	&E_CAST(12,$S,$L,$R,$K,@F1,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST(13,$S,$R,$L,$K,@F2,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST(14,$S,$L,$R,$K,@F3,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST(15,$S,$R,$L,$K,@F1,$tmp1,$tmp2,$tmp3,$tmp4);

    } else {

	&E_CAST(15,$S,$L,$R,$K,@F1,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST(14,$S,$R,$L,$K,@F3,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST(13,$S,$L,$R,$K,@F2,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST(12,$S,$R,$L,$K,@F1,$tmp1,$tmp2,$tmp3,$tmp4);

	&set_label('cast_dec_skip');

	&E_CAST(11,$S,$L,$R,$K,@F3,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST(10,$S,$R,$L,$K,@F2,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 9,$S,$L,$R,$K,@F1,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 8,$S,$R,$L,$K,@F3,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 7,$S,$L,$R,$K,@F2,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 6,$S,$R,$L,$K,@F1,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 5,$S,$L,$R,$K,@F3,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 4,$S,$R,$L,$K,@F2,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 3,$S,$L,$R,$K,@F1,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 2,$S,$R,$L,$K,@F3,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 1,$S,$L,$R,$K,@F2,$tmp1,$tmp2,$tmp3,$tmp4);

	&E_CAST( 0,$S,$R,$L,$K,@F1,$tmp1,$tmp2,$tmp3,$tmp4);

    }

    &set_label('cast_enc_done') if $enc;

# Why the nop? - Ben 17/1/99

    &nop(;;

    &mov($tmp3,&wparam(0));

    &mov(&DWP(4,$tmp3,"",0),$L);

    &mov(&DWP(0,$tmp3,"",0),$R);

    &function_end($name);

}

sub E_CAST {

    local($i,$S,$L,$R,$K,$OP1,$OP2,$OP3,$tmp1,$tmp2,$tmp3,$tmp4)=@_;

    # Ri needs to have 16 pre added.

    &comment("round $i");

    &mov(	$tmp4,		&DWP($i*8,$K,"",1));

    &mov(	$tmp1,		&DWP($i*8+4,$K,"",1));

    &$OP1(	$tmp4,		$R);

    &rotl(	$tmp4,		&LB($tmp1));

    if ($ppro) {

	&xor(	$tmp1,		$tmp1);

	&mov(	$tmp2,		0xff);

	&movb(	&LB($tmp1),	&HB($tmp4));	# A

	&and(	$tmp2,		$tmp4);

	&shr(	$tmp4,		16); 		#

	&xor(	$tmp3,		$tmp3);

    } else {

	&mov(	$tmp2,		$tmp4);		# B

	&movb(	&LB($tmp1),	&HB($tmp4));	# A	# BAD BAD BAD

	&shr(	$tmp4,		16); 		#

	&and(	$tmp2,		0xff);

    }

    &movb(	&LB($tmp3),	&HB($tmp4));	# C	# BAD BAD BAD

    &and(	$tmp4,		0xff);		# D

    &mov(	$tmp1,		&DWP($S1,"",$tmp1,4));

    &mov(	$tmp2,		&DWP($S2,"",$tmp2,4));

    &$OP2(	$tmp1,		$tmp2);

    &mov(	$tmp2,		&DWP($S3,"",$tmp3,4));

    &$OP3(	$tmp1,		$tmp2);

    &mov(	$tmp2,		&DWP($S4,"",$tmp4,4));

    &$OP1(	$tmp1,		$tmp2);

    # XXX

    &xor(	$L,		$tmp1);

    # XXX

}