crypto/des/asm/des-586.pl

   1 #!/usr/local/bin/perl
   2 #
   3 # The inner loop instruction sequence and the IP/FP modifications are from
   4 # Svend Olaf Mikkelsen <svolaf@inet.uni-c.dk>
   5 #
   6
   7 push(@INC,"perlasm","../../perlasm");
   8 require "x86asm.pl";
   9 require "cbc.pl";
  10 require "desboth.pl";
  11
  12 # base code is in microsft
  13 # op dest, source
  14 # format.
  15 #
  16
  17 &asm_init($ARGV[0],"des-586.pl");
  18
  19 $L="edi";
  20 $R="esi";
  21
  22 &external_label("DES_SPtrans");
  23 &DES_encrypt("DES_encrypt1",1);
  24 &DES_encrypt("DES_encrypt2",0);
  25 &DES_encrypt3("DES_encrypt3",1);
  26 &DES_encrypt3("DES_decrypt3",0);
  27 &cbc("DES_ncbc_encrypt","DES_encrypt1","DES_encrypt1",0,4,5,3,5,-1);
  28 &cbc("DES_ede3_cbc_encrypt","DES_encrypt3","DES_decrypt3",0,6,7,3,4,5);
  29
  30 &asm_finish();
  31
  32 sub DES_encrypt
  33         {
  34         local($name,$do_ip)=@_;
  35
  36         &function_begin_B($name,"EXTRN   _DES_SPtrans:DWORD");
  37
  38         &push("esi");
  39         &push("edi");
  40
  41         &comment("");
  42         &comment("Load the 2 words");
  43         $trans="ebp";
  44
  45         if ($do_ip)
  46                 {
  47                 &mov($R,&wparam(0));
  48                  &xor(  "ecx",          "ecx"           );
  49
  50                 &push("ebx");
  51                 &push("ebp");
  52
  53                 &mov("eax",&DWP(0,$R,"",0));
  54                  &mov("ebx",&wparam(2));        # get encrypt flag
  55                 &mov($L,&DWP(4,$R,"",0));
  56                 &comment("");
  57                 &comment("IP");
  58                 &IP_new("eax",$L,$R,3);
  59                 }
  60         else
  61                 {
  62                 &mov("eax",&wparam(0));
  63                  &xor(  "ecx",          "ecx"           );
  64
  65                 &push("ebx");
  66                 &push("ebp");
  67
  68                 &mov($R,&DWP(0,"eax","",0));
  69                  &mov("ebx",&wparam(2));        # get encrypt flag
  70                 &rotl($R,3);
  71                 &mov($L,&DWP(4,"eax","",0));
  72                 &rotl($L,3);
  73                 }
  74
  75         # PIC-ification:-)
  76         if ($cpp)       { &picmeup($trans,"DES_SPtrans");   }
  77         else            { &lea($trans,&DWP("DES_SPtrans")); }
  78
  79         &mov(   "ecx",  &wparam(1)      );
  80         &cmp("ebx","0");
  81         &je(&label("start_decrypt"));
  82
  83         for ($i=0; $i<16; $i+=2)
  84                 {
  85                 &comment("");
  86                 &comment("Round $i");
  87                 &D_ENCRYPT($i,$L,$R,$i*2,$trans,"eax","ebx","ecx","edx");
  88
  89                 &comment("");
  90                 &comment("Round ".sprintf("%d",$i+1));
  91                 &D_ENCRYPT($i+1,$R,$L,($i+1)*2,$trans,"eax","ebx","ecx","edx");
  92                 }
  93         &jmp(&label("end"));
  94
  95         &set_label("start_decrypt");
  96
  97         for ($i=15; $i>0; $i-=2)
  98                 {
  99                 &comment("");
 100                 &comment("Round $i");
 101                 &D_ENCRYPT(15-$i,$L,$R,$i*2,$trans,"eax","ebx","ecx","edx");
 102                 &comment("");
 103                 &comment("Round ".sprintf("%d",$i-1));
 104                 &D_ENCRYPT(15-$i+1,$R,$L,($i-1)*2,$trans,"eax","ebx","ecx","edx");
 105                 }
 106
 107         &set_label("end");
 108
 109         if ($do_ip)
 110                 {
 111                 &comment("");
 112                 &comment("FP");
 113                 &mov("edx",&wparam(0));
 114                 &FP_new($L,$R,"eax",3);
 115
 116                 &mov(&DWP(0,"edx","",0),"eax");
 117                 &mov(&DWP(4,"edx","",0),$R);
 118                 }
 119         else
 120                 {
 121                 &comment("");
 122                 &comment("Fixup");
 123                 &rotr($L,3);            # r
 124                  &mov("eax",&wparam(0));
 125                 &rotr($R,3);            # l
 126                  &mov(&DWP(0,"eax","",0),$L);
 127                  &mov(&DWP(4,"eax","",0),$R);
 128                 }
 129
 130         &pop("ebp");
 131         &pop("ebx");
 132         &pop("edi");
 133         &pop("esi");
 134         &ret();
 135
 136         &function_end_B($name);
 137         }
 138
 139 sub D_ENCRYPT
 140         {
 141         local($r,$L,$R,$S,$trans,$u,$tmp1,$tmp2,$t)=@_;
 142
 143          &mov(  $u,             &DWP(&n2a($S*4),$tmp2,"",0));
 144         &xor(   $tmp1,          $tmp1);
 145          &mov(  $t,             &DWP(&n2a(($S+1)*4),$tmp2,"",0));
 146         &xor(   $u,             $R);
 147         &xor(   $tmp2,          $tmp2);
 148          &xor(  $t,             $R);
 149         &and(   $u,             "0xfcfcfcfc"    );
 150          &and(  $t,             "0xcfcfcfcf"    );
 151         &movb(  &LB($tmp1),     &LB($u) );
 152          &movb( &LB($tmp2),     &HB($u) );
 153         &rotr(  $t,             4               );
 154         &xor(   $L,             &DWP("     ",$trans,$tmp1,0));
 155          &movb( &LB($tmp1),     &LB($t) );
 156          &xor(  $L,             &DWP("0x200",$trans,$tmp2,0));
 157          &movb( &LB($tmp2),     &HB($t) );
 158         &shr(   $u,             16);
 159          &xor(  $L,             &DWP("0x100",$trans,$tmp1,0));
 160          &movb( &LB($tmp1),     &HB($u) );
 161         &shr(   $t,             16);
 162          &xor(  $L,             &DWP("0x300",$trans,$tmp2,0));
 163         &movb(  &LB($tmp2),     &HB($t) );
 164          &and(  $u,             "0xff"  );
 165         &and(   $t,             "0xff"  );
 166          &xor(  $L,             &DWP("0x600",$trans,$tmp1,0));
 167          &xor(  $L,             &DWP("0x700",$trans,$tmp2,0));
 168         &mov(   $tmp2,          &wparam(1)      );
 169          &xor(  $L,             &DWP("0x400",$trans,$u,0));
 170          &xor(  $L,             &DWP("0x500",$trans,$t,0));
 171         }
 172
 173 sub n2a
 174         {
 175         sprintf("%d",$_[0]);
 176         }
 177
 178 # now has a side affect of rotating $a by $shift
 179 sub R_PERM_OP
 180         {
 181         local($a,$b,$tt,$shift,$mask,$last)=@_;
 182
 183         &rotl(  $a,             $shift          ) if ($shift != 0);
 184         &mov(   $tt,            $a              );
 185         &xor(   $a,             $b              );
 186         &and(   $a,             $mask           );
 187         # This can never succeed, and besides it is difficult to see what the
 188         # idea was - Ben 13 Feb 99
 189         if (!$last eq $b)
 190                 {
 191                 &xor(   $b,             $a              );
 192                 &xor(   $tt,            $a              );
 193                 }
 194         else
 195                 {
 196                 &xor(   $tt,            $a              );
 197                 &xor(   $b,             $a              );
 198                 }
 199         &comment("");
 200         }
 201
 202 sub IP_new
 203         {
 204         local($l,$r,$tt,$lr)=@_;
 205
 206         &R_PERM_OP($l,$r,$tt, 4,"0xf0f0f0f0",$l);
 207         &R_PERM_OP($r,$tt,$l,20,"0xfff0000f",$l);
 208         &R_PERM_OP($l,$tt,$r,14,"0x33333333",$r);
 209         &R_PERM_OP($tt,$r,$l,22,"0x03fc03fc",$r);
 210         &R_PERM_OP($l,$r,$tt, 9,"0xaaaaaaaa",$r);
 211
 212         if ($lr != 3)
 213                 {
 214                 if (($lr-3) < 0)
 215                         { &rotr($tt,    3-$lr); }
 216                 else    { &rotl($tt,    $lr-3); }
 217                 }
 218         if ($lr != 2)
 219                 {
 220                 if (($lr-2) < 0)
 221                         { &rotr($r,     2-$lr); }
 222                 else    { &rotl($r,     $lr-2); }
 223                 }
 224         }
 225
 226 sub FP_new
 227         {
 228         local($l,$r,$tt,$lr)=@_;
 229
 230         if ($lr != 2)
 231                 {
 232                 if (($lr-2) < 0)
 233                         { &rotl($r,     2-$lr); }
 234                 else    { &rotr($r,     $lr-2); }
 235                 }
 236         if ($lr != 3)
 237                 {
 238                 if (($lr-3) < 0)
 239                         { &rotl($l,     3-$lr); }
 240                 else    { &rotr($l,     $lr-3); }
 241                 }
 242
 243         &R_PERM_OP($l,$r,$tt, 0,"0xaaaaaaaa",$r);
 244         &R_PERM_OP($tt,$r,$l,23,"0x03fc03fc",$r);
 245         &R_PERM_OP($l,$r,$tt,10,"0x33333333",$l);
 246         &R_PERM_OP($r,$tt,$l,18,"0xfff0000f",$l);
 247         &R_PERM_OP($l,$tt,$r,12,"0xf0f0f0f0",$r);
 248         &rotr($tt       , 4);
 249         }
 250