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