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      1 #!/usr/local/bin/perl
      2 #
      3 # The inner loop instruction sequence and the IP/FP modifications are from
      4 # Svend Olaf Mikkelsen <svolaf (at] inet.uni-c.dk>
      5 # I've added the stuff needed for crypt() but I've not worried about making
      6 # things perfect.
      7 #
      8 
      9 push(@INC,"perlasm","../../perlasm");
     10 require "x86asm.pl";
     11 
     12 &asm_init($ARGV[0],"crypt586.pl");
     13 
     14 $L="edi";
     15 $R="esi";
     16 
     17 &external_label("DES_SPtrans");
     18 &fcrypt_body("fcrypt_body");
     19 &asm_finish();
     20 
     21 sub fcrypt_body
     22 	{
     23 	local($name,$do_ip)=@_;
     24 
     25 	&function_begin($name,"EXTRN   _DES_SPtrans:DWORD");
     26 
     27 	&comment("");
     28 	&comment("Load the 2 words");
     29 	$trans="ebp";
     30 
     31 	&xor(	$L,	$L);
     32 	&xor(	$R,	$R);
     33 
     34 	# PIC-ification:-)
     35 	&picmeup("edx","DES_SPtrans");
     36 	#if ($cpp)	{ &picmeup("edx","DES_SPtrans");   }
     37 	#else		{ &lea("edx",&DWP("DES_SPtrans")); }
     38 	&push("edx");	# becomes &swtmp(1)
     39 	#
     40 	&mov($trans,&wparam(1)); # reloaded with DES_SPtrans in D_ENCRYPT
     41 
     42 	&push(&DWC(25)); # add a variable
     43 
     44 	&set_label("start");
     45 	for ($i=0; $i<16; $i+=2)
     46 		{
     47 		&comment("");
     48 		&comment("Round $i");
     49 		&D_ENCRYPT($i,$L,$R,$i*2,$trans,"eax","ebx","ecx","edx");
     50 
     51 		&comment("");
     52 		&comment("Round ".sprintf("%d",$i+1));
     53 		&D_ENCRYPT($i+1,$R,$L,($i+1)*2,$trans,"eax","ebx","ecx","edx");
     54 		}
     55 	 &mov("ebx",	&swtmp(0));
     56 	&mov("eax",	$L);
     57 	 &dec("ebx");
     58 	&mov($L,	$R);
     59 	 &mov($R,	"eax");
     60 	&mov(&swtmp(0),	"ebx");
     61 	 &jnz(&label("start"));
     62 
     63 	&comment("");
     64 	&comment("FP");
     65 	&mov("edx",&wparam(0));
     66 
     67 	&FP_new($R,$L,"eax",3);
     68 	&mov(&DWP(0,"edx","",0),"eax");
     69 	&mov(&DWP(4,"edx","",0),$L);
     70 
     71 	&add("esp",8);	# remove variables
     72 
     73 	&function_end($name);
     74 	}
     75 
     76 sub D_ENCRYPT
     77 	{
     78 	local($r,$L,$R,$S,$trans,$u,$tmp1,$tmp2,$t)=@_;
     79 
     80 	&mov(	$u,		&wparam(2));			# 2
     81 	&mov(	$t,		$R);
     82 	&shr(	$t,		16);				# 1
     83 	&mov(	$tmp2,		&wparam(3));			# 2
     84 	&xor(	$t,		$R);				# 1
     85 
     86 	&and(	$u,		$t);				# 2
     87 	&and(	$t,		$tmp2);				# 2
     88 
     89 	&mov(	$tmp1,		$u);
     90 	&shl(	$tmp1,		16); 				# 1
     91 	&mov(	$tmp2,		$t);
     92 	&shl(	$tmp2,		16); 				# 1
     93 	&xor(	$u,		$tmp1);				# 2
     94 	&xor(	$t,		$tmp2);				# 2
     95 	&mov(	$tmp1,		&DWP(&n2a($S*4),$trans,"",0));	# 2
     96 	&xor(	$u,		$tmp1);
     97 	&mov(	$tmp2,		&DWP(&n2a(($S+1)*4),$trans,"",0));	# 2
     98 	&xor(	$u,		$R);
     99 	&xor(	$t,		$R);
    100 	&xor(	$t,		$tmp2);
    101 
    102 	&and(	$u,		"0xfcfcfcfc"	);		# 2
    103 	&xor(	$tmp1,		$tmp1);				# 1
    104 	&and(	$t,		"0xcfcfcfcf"	);		# 2
    105 	&xor(	$tmp2,		$tmp2);	
    106 	&movb(	&LB($tmp1),	&LB($u)	);
    107 	&movb(	&LB($tmp2),	&HB($u)	);
    108 	&rotr(	$t,		4		);
    109 	&mov(	$trans,		&swtmp(1));
    110 	&xor(	$L,		&DWP("     ",$trans,$tmp1,0));
    111 	&movb(	&LB($tmp1),	&LB($t)	);
    112 	&xor(	$L,		&DWP("0x200",$trans,$tmp2,0));
    113 	&movb(	&LB($tmp2),	&HB($t)	);
    114 	&shr(	$u,		16);
    115 	&xor(	$L,		&DWP("0x100",$trans,$tmp1,0));
    116 	&movb(	&LB($tmp1),	&HB($u)	);
    117 	&shr(	$t,		16);
    118 	&xor(	$L,		&DWP("0x300",$trans,$tmp2,0));
    119 	&movb(	&LB($tmp2),	&HB($t)	);
    120 	&and(	$u,		"0xff"	);
    121 	&and(	$t,		"0xff"	);
    122 	&mov(	$tmp1,		&DWP("0x600",$trans,$tmp1,0));
    123 	&xor(	$L,		$tmp1);
    124 	&mov(	$tmp1,		&DWP("0x700",$trans,$tmp2,0));
    125 	&xor(	$L,		$tmp1);
    126 	&mov(	$tmp1,		&DWP("0x400",$trans,$u,0));
    127 	&xor(	$L,		$tmp1);
    128 	&mov(	$tmp1,		&DWP("0x500",$trans,$t,0));
    129 	&xor(	$L,		$tmp1);
    130 	&mov(	$trans,		&wparam(1));
    131 	}
    132 
    133 sub n2a
    134 	{
    135 	sprintf("%d",$_[0]);
    136 	}
    137 
    138 # now has a side affect of rotating $a by $shift
    139 sub R_PERM_OP
    140 	{
    141 	local($a,$b,$tt,$shift,$mask,$last)=@_;
    142 
    143 	&rotl(	$a,		$shift		) if ($shift != 0);
    144 	&mov(	$tt,		$a		);
    145 	&xor(	$a,		$b		);
    146 	&and(	$a,		$mask		);
    147 	if ($notlast eq $b)
    148 		{
    149 		&xor(	$b,		$a		);
    150 		&xor(	$tt,		$a		);
    151 		}
    152 	else
    153 		{
    154 		&xor(	$tt,		$a		);
    155 		&xor(	$b,		$a		);
    156 		}
    157 	&comment("");
    158 	}
    159 
    160 sub IP_new
    161 	{
    162 	local($l,$r,$tt,$lr)=@_;
    163 
    164 	&R_PERM_OP($l,$r,$tt, 4,"0xf0f0f0f0",$l);
    165 	&R_PERM_OP($r,$tt,$l,20,"0xfff0000f",$l);
    166 	&R_PERM_OP($l,$tt,$r,14,"0x33333333",$r);
    167 	&R_PERM_OP($tt,$r,$l,22,"0x03fc03fc",$r);
    168 	&R_PERM_OP($l,$r,$tt, 9,"0xaaaaaaaa",$r);
    169 	
    170 	if ($lr != 3)
    171 		{
    172 		if (($lr-3) < 0)
    173 			{ &rotr($tt,	3-$lr); }
    174 		else	{ &rotl($tt,	$lr-3); }
    175 		}
    176 	if ($lr != 2)
    177 		{
    178 		if (($lr-2) < 0)
    179 			{ &rotr($r,	2-$lr); }
    180 		else	{ &rotl($r,	$lr-2); }
    181 		}
    182 	}
    183 
    184 sub FP_new
    185 	{
    186 	local($l,$r,$tt,$lr)=@_;
    187 
    188 	if ($lr != 2)
    189 		{
    190 		if (($lr-2) < 0)
    191 			{ &rotl($r,	2-$lr); }
    192 		else	{ &rotr($r,	$lr-2); }
    193 		}
    194 	if ($lr != 3)
    195 		{
    196 		if (($lr-3) < 0)
    197 			{ &rotl($l,	3-$lr); }
    198 		else	{ &rotr($l,	$lr-3); }
    199 		}
    200 
    201 	&R_PERM_OP($l,$r,$tt, 0,"0xaaaaaaaa",$r);
    202 	&R_PERM_OP($tt,$r,$l,23,"0x03fc03fc",$r);
    203 	&R_PERM_OP($l,$r,$tt,10,"0x33333333",$l);
    204 	&R_PERM_OP($r,$tt,$l,18,"0xfff0000f",$l);
    205 	&R_PERM_OP($l,$tt,$r,12,"0xf0f0f0f0",$r);
    206 	&rotr($tt	, 4);
    207 	}
    208 
    209