crypto/bf/asm/bf-686.pl

   1 #!/usr/local/bin/perl
   2 #!/usr/local/bin/perl
   3
   4 push(@INC,"perlasm","../../perlasm");
   5 require "x86asm.pl";
   6 require "cbc.pl";
   7
   8 &asm_init($ARGV[0],"bf-686.pl");
   9
  10 $BF_ROUNDS=16;
  11 $BF_OFF=($BF_ROUNDS+2)*4;
  12 $L="ecx";
  13 $R="edx";
  14 $P="edi";
  15 $tot="esi";
  16 $tmp1="eax";
  17 $tmp2="ebx";
  18 $tmp3="ebp";
  19
  20 &des_encrypt("BF_encrypt",1);
  21 &des_encrypt("BF_decrypt",0);
  22 &cbc("BF_cbc_encrypt","BF_encrypt","BF_decrypt",1,4,5,3,-1,-1);
  23
  24 &asm_finish();
  25
  26 &file_end();
  27
  28 sub des_encrypt
  29         {
  30         local($name,$enc)=@_;
  31
  32         &function_begin($name,"");
  33
  34         &comment("");
  35         &comment("Load the 2 words");
  36         &mov("eax",&wparam(0));
  37         &mov($L,&DWP(0,"eax","",0));
  38         &mov($R,&DWP(4,"eax","",0));
  39
  40         &comment("");
  41         &comment("P pointer, s and enc flag");
  42         &mov($P,&wparam(1));
  43
  44         &xor(   $tmp1,  $tmp1);
  45         &xor(   $tmp2,  $tmp2);
  46
  47         # encrypting part
  48
  49         if ($enc)
  50                 {
  51                 &xor($L,&DWP(0,$P,"",0));
  52                 for ($i=0; $i<$BF_ROUNDS; $i+=2)
  53                         {
  54                         &comment("");
  55                         &comment("Round $i");
  56                         &BF_ENCRYPT($i+1,$R,$L,$P,$tot,$tmp1,$tmp2,$tmp3);
  57
  58                         &comment("");
  59                         &comment("Round ".sprintf("%d",$i+1));
  60                         &BF_ENCRYPT($i+2,$L,$R,$P,$tot,$tmp1,$tmp2,$tmp3);
  61                         }
  62                 &xor($R,&DWP(($BF_ROUNDS+1)*4,$P,"",0));
  63
  64                 &mov("eax",&wparam(0));
  65                 &mov(&DWP(0,"eax","",0),$R);
  66                 &mov(&DWP(4,"eax","",0),$L);
  67                 &function_end_A($name);
  68                 }
  69         else
  70                 {
  71                 &xor($L,&DWP(($BF_ROUNDS+1)*4,$P,"",0));
  72                 for ($i=$BF_ROUNDS; $i>0; $i-=2)
  73                         {
  74                         &comment("");
  75                         &comment("Round $i");
  76                         &BF_ENCRYPT($i,$R,$L,$P,$tot,$tmp1,$tmp2,$tmp3);
  77                         &comment("");
  78                         &comment("Round ".sprintf("%d",$i-1));
  79                         &BF_ENCRYPT($i-1,$L,$R,$P,$tot,$tmp1,$tmp2,$tmp3);
  80                         }
  81                 &xor($R,&DWP(0,$P,"",0));
  82
  83                 &mov("eax",&wparam(0));
  84                 &mov(&DWP(0,"eax","",0),$R);
  85                 &mov(&DWP(4,"eax","",0),$L);
  86                 &function_end_A($name);
  87                 }
  88
  89         &function_end_B($name);
  90         }
  91
  92 sub BF_ENCRYPT
  93         {
  94         local($i,$L,$R,$P,$tot,$tmp1,$tmp2,$tmp3)=@_;
  95
  96         &rotr(  $R,             16);
  97         &mov(   $tot,           &DWP(&n2a($i*4),$P,"",0));
  98
  99         &movb(  &LB($tmp1),     &HB($R));
 100         &movb(  &LB($tmp2),     &LB($R));
 101
 102         &rotr(  $R,             16);
 103         &xor(   $L,             $tot);
 104
 105         &mov(   $tot,           &DWP(&n2a($BF_OFF+0x0000),$P,$tmp1,4));
 106         &mov(   $tmp3,          &DWP(&n2a($BF_OFF+0x0400),$P,$tmp2,4));
 107
 108         &movb(  &LB($tmp1),     &HB($R));
 109         &movb(  &LB($tmp2),     &LB($R));
 110
 111         &add(   $tot,           $tmp3);
 112         &mov(   $tmp1,          &DWP(&n2a($BF_OFF+0x0800),$P,$tmp1,4)); # delay
 113
 114         &xor(   $tot,           $tmp1);
 115         &mov(   $tmp3,          &DWP(&n2a($BF_OFF+0x0C00),$P,$tmp2,4));
 116
 117         &add(   $tot,           $tmp3);
 118         &xor(   $tmp1,          $tmp1);
 119
 120         &xor(   $L,             $tot);
 121         # delay
 122         }
 123
 124 sub n2a
 125         {
 126         sprintf("%d",$_[0]);
 127         }
 128