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         $ks="ebp";
  44
  45         if ($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         &mov(   $ks,            &wparam(1)      );
  76         &cmp("ebx","0");
  77         &je(&label("start_decrypt"));
  78
  79         for ($i=0; $i<16; $i+=2)
  80                 {
  81                 &comment("");
  82                 &comment("Round $i");
  83                 &D_ENCRYPT($i,$L,$R,$i*2,$ks,"des_SPtrans","eax","ebx","ecx","edx");
  84
  85                 &comment("");
  86                 &comment("Round ".sprintf("%d",$i+1));
  87                 &D_ENCRYPT($i+1,$R,$L,($i+1)*2,$ks,"des_SPtrans","eax","ebx","ecx","edx");
  88                 }
  89         &jmp(&label("end"));
  90
  91         &set_label("start_decrypt");
  92
  93         for ($i=15; $i>0; $i-=2)
  94                 {
  95                 &comment("");
  96                 &comment("Round $i");
  97                 &D_ENCRYPT(15-$i,$L,$R,$i*2,$ks,"des_SPtrans","eax","ebx","ecx","edx");
  98                 &comment("");
  99                 &comment("Round ".sprintf("%d",$i-1));
 100                 &D_ENCRYPT(15-$i+1,$R,$L,($i-1)*2,$ks,"des_SPtrans","eax","ebx","ecx","edx");
 101                 }
 102
 103         &set_label("end");
 104
 105         if ($do_ip)
 106                 {
 107                 &comment("");
 108                 &comment("FP");
 109                 &mov("edx",&wparam(0));
 110                 &FP_new($L,$R,"eax",3);
 111
 112                 &mov(&DWP(0,"edx","",0),"eax");
 113                 &mov(&DWP(4,"edx","",0),$R);
 114                 }
 115         else
 116                 {
 117                 &comment("");
 118                 &comment("Fixup");
 119                 &rotr($L,3);            # r
 120                  &mov("eax",&wparam(0));
 121                 &rotr($R,3);            # l
 122                  &mov(&DWP(0,"eax","",0),$L);
 123                  &mov(&DWP(4,"eax","",0),$R);
 124                 }
 125
 126         &pop("ebp");
 127         &pop("ebx");
 128         &pop("edi");
 129         &pop("esi");
 130         &ret();
 131
 132         &function_end_B($name);
 133         }
 134
 135 sub D_ENCRYPT
 136         {
 137         local($r,$L,$R,$S,$ks,$desSP,$u,$tmp1,$tmp2,$t)=@_;
 138
 139          &mov(  $u,             &DWP(&n2a($S*4),$ks,"",0));
 140         &xor(   $tmp1,          $tmp1);
 141          &mov(  $t,             &DWP(&n2a(($S+1)*4),$ks,"",0));
 142         &xor(   $u,             $R);
 143          &xor(  $t,             $R);
 144         &and(   $u,             "0xfcfcfcfc"    );
 145          &and(  $t,             "0xcfcfcfcf"    );
 146         &movb(  &LB($tmp1),     &LB($u) );
 147          &movb( &LB($tmp2),     &HB($u) );
 148         &rotr(  $t,             4               );
 149         &mov(   $ks,            &DWP("      $desSP",$tmp1,"",0));
 150          &movb( &LB($tmp1),     &LB($t) );
 151         &xor(   $L,             $ks);
 152          &mov(  $ks,            &DWP("0x200+$desSP",$tmp2,"",0));
 153         &xor(   $L,             $ks); ######
 154          &movb( &LB($tmp2),     &HB($t) );
 155         &shr(   $u,             16);
 156          &mov(  $ks,            &DWP("0x100+$desSP",$tmp1,"",0));
 157         &xor(   $L,             $ks); ######
 158          &movb( &LB($tmp1),     &HB($u) );
 159         &shr(   $t,             16);
 160          &mov(  $ks,            &DWP("0x300+$desSP",$tmp2,"",0));
 161         &xor(   $L,             $ks);
 162          &mov(  $ks,            &wparam(1)      );
 163         &movb(  &LB($tmp2),     &HB($t) );
 164          &and(  $u,             "0xff"  );
 165         &and(   $t,             "0xff"  );
 166          &mov(  $tmp1,          &DWP("0x600+$desSP",$tmp1,"",0));
 167         &xor(   $L,             $tmp1);
 168          &mov(  $tmp1,          &DWP("0x700+$desSP",$tmp2,"",0));
 169         &xor(   $L,             $tmp1);
 170          &mov(  $tmp1,          &DWP("0x400+$desSP",$u,"",0));
 171         &xor(   $L,             $tmp1);
 172          &mov(  $tmp1,          &DWP("0x500+$desSP",$t,"",0));
 173         &xor(   $L,             $tmp1);
 174         }
 175
 176 sub n2a
 177         {
 178         sprintf("%d",$_[0]);
 179         }
 180
 181 # now has a side affect of rotating $a by $shift
 182 sub R_PERM_OP
 183         {
 184         local($a,$b,$tt,$shift,$mask,$last)=@_;
 185
 186         &rotl(  $a,             $shift          ) if ($shift != 0);
 187         &mov(   $tt,            $a              );
 188         &xor(   $a,             $b              );
 189         &and(   $a,             $mask           );
 190         # This can never succeed, and besides it is difficult to see what the
 191         # idea was - Ben 13 Feb 99
 192         if (!$last eq $b)
 193                 {
 194                 &xor(   $b,             $a              );
 195                 &xor(   $tt,            $a              );
 196                 }
 197         else
 198                 {
 199                 &xor(   $tt,            $a              );
 200                 &xor(   $b,             $a              );
 201                 }
 202         &comment("");
 203         }
 204
 205 sub IP_new
 206         {
 207         local($l,$r,$tt,$lr)=@_;
 208
 209         &R_PERM_OP($l,$r,$tt, 4,"0xf0f0f0f0",$l);
 210         &R_PERM_OP($r,$tt,$l,20,"0xfff0000f",$l);
 211         &R_PERM_OP($l,$tt,$r,14,"0x33333333",$r);
 212         &R_PERM_OP($tt,$r,$l,22,"0x03fc03fc",$r);
 213         &R_PERM_OP($l,$r,$tt, 9,"0xaaaaaaaa",$r);
 214
 215         if ($lr != 3)
 216                 {
 217                 if (($lr-3) < 0)
 218                         { &rotr($tt,    3-$lr); }
 219                 else    { &rotl($tt,    $lr-3); }
 220                 }
 221         if ($lr != 2)
 222                 {
 223                 if (($lr-2) < 0)
 224                         { &rotr($r,     2-$lr); }
 225                 else    { &rotl($r,     $lr-2); }
 226                 }
 227         }
 228
 229 sub FP_new
 230         {
 231         local($l,$r,$tt,$lr)=@_;
 232
 233         if ($lr != 2)
 234                 {
 235                 if (($lr-2) < 0)
 236                         { &rotl($r,     2-$lr); }
 237                 else    { &rotr($r,     $lr-2); }
 238                 }
 239         if ($lr != 3)
 240                 {
 241                 if (($lr-3) < 0)
 242                         { &rotl($l,     3-$lr); }
 243                 else    { &rotr($l,     $lr-3); }
 244                 }
 245
 246         &R_PERM_OP($l,$r,$tt, 0,"0xaaaaaaaa",$r);
 247         &R_PERM_OP($tt,$r,$l,23,"0x03fc03fc",$r);
 248         &R_PERM_OP($l,$r,$tt,10,"0x33333333",$l);
 249         &R_PERM_OP($r,$tt,$l,18,"0xfff0000f",$l);
 250         &R_PERM_OP($l,$tt,$r,12,"0xf0f0f0f0",$r);
 251         &rotr($tt       , 4);
 252         }
 253