1#!/usr/local/bin/perl 2 3push(@INC,"perlasm","../../perlasm"); 4require "x86asm.pl"; 5require "cbc.pl"; 6 7&asm_init($ARGV[0],"bf-586.pl",$ARGV[$#ARGV] eq "386"); 8 9$BF_ROUNDS=16; 10$BF_OFF=($BF_ROUNDS+2)*4; 11$L="edi"; 12$R="esi"; 13$P="ebp"; 14$tmp1="eax"; 15$tmp2="ebx"; 16$tmp3="ecx"; 17$tmp4="edx"; 18 19&BF_encrypt("BF_encrypt",1); 20&BF_encrypt("BF_decrypt",0); 21&cbc("BF_cbc_encrypt","BF_encrypt","BF_decrypt",1,4,5,3,-1,-1); 22&asm_finish(); 23 24sub BF_encrypt 25 { 26 local($name,$enc)=@_; 27 28 &function_begin_B($name,""); 29 30 &comment(""); 31 32 &push("ebp"); 33 &push("ebx"); 34 &mov($tmp2,&wparam(0)); 35 &mov($P,&wparam(1)); 36 &push("esi"); 37 &push("edi"); 38 39 &comment("Load the 2 words"); 40 &mov($L,&DWP(0,$tmp2,"",0)); 41 &mov($R,&DWP(4,$tmp2,"",0)); 42 43 &xor( $tmp1, $tmp1); 44 45 # encrypting part 46 47 if ($enc) 48 { 49 &mov($tmp2,&DWP(0,$P,"",0)); 50 &xor( $tmp3, $tmp3); 51 52 &xor($L,$tmp2); 53 for ($i=0; $i<$BF_ROUNDS; $i+=2) 54 { 55 &comment(""); 56 &comment("Round $i"); 57 &BF_ENCRYPT($i+1,$R,$L,$P,$tmp1,$tmp2,$tmp3,$tmp4,1); 58 59 &comment(""); 60 &comment("Round ".sprintf("%d",$i+1)); 61 &BF_ENCRYPT($i+2,$L,$R,$P,$tmp1,$tmp2,$tmp3,$tmp4,1); 62 } 63 # &mov($tmp1,&wparam(0)); In last loop 64 &mov($tmp4,&DWP(($BF_ROUNDS+1)*4,$P,"",0)); 65 } 66 else 67 { 68 &mov($tmp2,&DWP(($BF_ROUNDS+1)*4,$P,"",0)); 69 &xor( $tmp3, $tmp3); 70 71 &xor($L,$tmp2); 72 for ($i=$BF_ROUNDS; $i>0; $i-=2) 73 { 74 &comment(""); 75 &comment("Round $i"); 76 &BF_ENCRYPT($i,$R,$L,$P,$tmp1,$tmp2,$tmp3,$tmp4,0); 77 &comment(""); 78 &comment("Round ".sprintf("%d",$i-1)); 79 &BF_ENCRYPT($i-1,$L,$R,$P,$tmp1,$tmp2,$tmp3,$tmp4,0); 80 } 81 # &mov($tmp1,&wparam(0)); In last loop 82 &mov($tmp4,&DWP(0,$P,"",0)); 83 } 84 85 &xor($R,$tmp4); 86 &mov(&DWP(4,$tmp1,"",0),$L); 87 88 &mov(&DWP(0,$tmp1,"",0),$R); 89 &function_end($name); 90 } 91 92sub BF_ENCRYPT 93 { 94 local($i,$L,$R,$P,$tmp1,$tmp2,$tmp3,$tmp4,$enc)=@_; 95 96 &mov( $tmp4, &DWP(&n2a($i*4),$P,"",0)); # for next round 97 98 &mov( $tmp2, $R); 99 &xor( $L, $tmp4); 100 101 &shr( $tmp2, 16); 102 &mov( $tmp4, $R); 103 104 &movb( &LB($tmp1), &HB($tmp2)); # A 105 &and( $tmp2, 0xff); # B 106 107 &movb( &LB($tmp3), &HB($tmp4)); # C 108 &and( $tmp4, 0xff); # D 109 110 &mov( $tmp1, &DWP(&n2a($BF_OFF+0x0000),$P,$tmp1,4)); 111 &mov( $tmp2, &DWP(&n2a($BF_OFF+0x0400),$P,$tmp2,4)); 112 113 &add( $tmp2, $tmp1); 114 &mov( $tmp1, &DWP(&n2a($BF_OFF+0x0800),$P,$tmp3,4)); 115 116 &xor( $tmp2, $tmp1); 117 &mov( $tmp4, &DWP(&n2a($BF_OFF+0x0C00),$P,$tmp4,4)); 118 119 &add( $tmp2, $tmp4); 120 if (($enc && ($i != 16)) || ((!$enc) && ($i != 1))) 121 { &xor( $tmp1, $tmp1); } 122 else 123 { 124 &comment("Load parameter 0 ($i) enc=$enc"); 125 &mov($tmp1,&wparam(0)); 126 } # In last loop 127 128 &xor( $L, $tmp2); 129 # delay 130 } 131 132sub n2a 133 { 134 sprintf("%d",$_[0]); 135 } 136 137