1 #!/usr/local/bin/perl 2 # 3 # The inner loop instruction sequence and the IP/FP modifications are from 4 # Svend Olaf Mikkelsen <svolaf (at] inet.uni-c.dk> 5 # I've added the stuff needed for crypt() but I've not worried about making 6 # things perfect. 7 # 8 9 $0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1; 10 push(@INC,"${dir}","${dir}../../perlasm"); 11 require "x86asm.pl"; 12 13 &asm_init($ARGV[0],"crypt586.pl"); 14 15 $L="edi"; 16 $R="esi"; 17 18 &external_label("DES_SPtrans"); 19 &fcrypt_body("fcrypt_body"); 20 &asm_finish(); 21 22 sub fcrypt_body 23 { 24 local($name,$do_ip)=@_; 25 26 &function_begin($name); 27 28 &comment(""); 29 &comment("Load the 2 words"); 30 $trans="ebp"; 31 32 &xor( $L, $L); 33 &xor( $R, $R); 34 35 # PIC-ification:-) 36 &picmeup("edx","DES_SPtrans"); 37 #if ($cpp) { &picmeup("edx","DES_SPtrans"); } 38 #else { &lea("edx",&DWP("DES_SPtrans")); } 39 &push("edx"); # becomes &swtmp(1) 40 # 41 &mov($trans,&wparam(1)); # reloaded with DES_SPtrans in D_ENCRYPT 42 43 &push(&DWC(25)); # add a variable 44 45 &set_label("start"); 46 for ($i=0; $i<16; $i+=2) 47 { 48 &comment(""); 49 &comment("Round $i"); 50 &D_ENCRYPT($i,$L,$R,$i*2,$trans,"eax","ebx","ecx","edx"); 51 52 &comment(""); 53 &comment("Round ".sprintf("%d",$i+1)); 54 &D_ENCRYPT($i+1,$R,$L,($i+1)*2,$trans,"eax","ebx","ecx","edx"); 55 } 56 &mov("ebx", &swtmp(0)); 57 &mov("eax", $L); 58 &dec("ebx"); 59 &mov($L, $R); 60 &mov($R, "eax"); 61 &mov(&swtmp(0), "ebx"); 62 &jnz(&label("start")); 63 64 &comment(""); 65 &comment("FP"); 66 &mov("edx",&wparam(0)); 67 68 &FP_new($R,$L,"eax",3); 69 &mov(&DWP(0,"edx","",0),"eax"); 70 &mov(&DWP(4,"edx","",0),$L); 71 72 &add("esp",8); # remove variables 73 74 &function_end($name); 75 } 76 77 sub D_ENCRYPT 78 { 79 local($r,$L,$R,$S,$trans,$u,$tmp1,$tmp2,$t)=@_; 80 81 &mov( $u, &wparam(2)); # 2 82 &mov( $t, $R); 83 &shr( $t, 16); # 1 84 &mov( $tmp2, &wparam(3)); # 2 85 &xor( $t, $R); # 1 86 87 &and( $u, $t); # 2 88 &and( $t, $tmp2); # 2 89 90 &mov( $tmp1, $u); 91 &shl( $tmp1, 16); # 1 92 &mov( $tmp2, $t); 93 &shl( $tmp2, 16); # 1 94 &xor( $u, $tmp1); # 2 95 &xor( $t, $tmp2); # 2 96 &mov( $tmp1, &DWP(&n2a($S*4),$trans,"",0)); # 2 97 &xor( $u, $tmp1); 98 &mov( $tmp2, &DWP(&n2a(($S+1)*4),$trans,"",0)); # 2 99 &xor( $u, $R); 100 &xor( $t, $R); 101 &xor( $t, $tmp2); 102 103 &and( $u, "0xfcfcfcfc" ); # 2 104 &xor( $tmp1, $tmp1); # 1 105 &and( $t, "0xcfcfcfcf" ); # 2 106 &xor( $tmp2, $tmp2); 107 &movb( &LB($tmp1), &LB($u) ); 108 &movb( &LB($tmp2), &HB($u) ); 109 &rotr( $t, 4 ); 110 &mov( $trans, &swtmp(1)); 111 &xor( $L, &DWP(" ",$trans,$tmp1,0)); 112 &movb( &LB($tmp1), &LB($t) ); 113 &xor( $L, &DWP("0x200",$trans,$tmp2,0)); 114 &movb( &LB($tmp2), &HB($t) ); 115 &shr( $u, 16); 116 &xor( $L, &DWP("0x100",$trans,$tmp1,0)); 117 &movb( &LB($tmp1), &HB($u) ); 118 &shr( $t, 16); 119 &xor( $L, &DWP("0x300",$trans,$tmp2,0)); 120 &movb( &LB($tmp2), &HB($t) ); 121 &and( $u, "0xff" ); 122 &and( $t, "0xff" ); 123 &mov( $tmp1, &DWP("0x600",$trans,$tmp1,0)); 124 &xor( $L, $tmp1); 125 &mov( $tmp1, &DWP("0x700",$trans,$tmp2,0)); 126 &xor( $L, $tmp1); 127 &mov( $tmp1, &DWP("0x400",$trans,$u,0)); 128 &xor( $L, $tmp1); 129 &mov( $tmp1, &DWP("0x500",$trans,$t,0)); 130 &xor( $L, $tmp1); 131 &mov( $trans, &wparam(1)); 132 } 133 134 sub n2a 135 { 136 sprintf("%d",$_[0]); 137 } 138 139 # now has a side affect of rotating $a by $shift 140 sub R_PERM_OP 141 { 142 local($a,$b,$tt,$shift,$mask,$last)=@_; 143 144 &rotl( $a, $shift ) if ($shift != 0); 145 &mov( $tt, $a ); 146 &xor( $a, $b ); 147 &and( $a, $mask ); 148 if ($notlast eq $b) 149 { 150 &xor( $b, $a ); 151 &xor( $tt, $a ); 152 } 153 else 154 { 155 &xor( $tt, $a ); 156 &xor( $b, $a ); 157 } 158 &comment(""); 159 } 160 161 sub IP_new 162 { 163 local($l,$r,$tt,$lr)=@_; 164 165 &R_PERM_OP($l,$r,$tt, 4,"0xf0f0f0f0",$l); 166 &R_PERM_OP($r,$tt,$l,20,"0xfff0000f",$l); 167 &R_PERM_OP($l,$tt,$r,14,"0x33333333",$r); 168 &R_PERM_OP($tt,$r,$l,22,"0x03fc03fc",$r); 169 &R_PERM_OP($l,$r,$tt, 9,"0xaaaaaaaa",$r); 170 171 if ($lr != 3) 172 { 173 if (($lr-3) < 0) 174 { &rotr($tt, 3-$lr); } 175 else { &rotl($tt, $lr-3); } 176 } 177 if ($lr != 2) 178 { 179 if (($lr-2) < 0) 180 { &rotr($r, 2-$lr); } 181 else { &rotl($r, $lr-2); } 182 } 183 } 184 185 sub FP_new 186 { 187 local($l,$r,$tt,$lr)=@_; 188 189 if ($lr != 2) 190 { 191 if (($lr-2) < 0) 192 { &rotl($r, 2-$lr); } 193 else { &rotr($r, $lr-2); } 194 } 195 if ($lr != 3) 196 { 197 if (($lr-3) < 0) 198 { &rotl($l, 3-$lr); } 199 else { &rotr($l, $lr-3); } 200 } 201 202 &R_PERM_OP($l,$r,$tt, 0,"0xaaaaaaaa",$r); 203 &R_PERM_OP($tt,$r,$l,23,"0x03fc03fc",$r); 204 &R_PERM_OP($l,$r,$tt,10,"0x33333333",$l); 205 &R_PERM_OP($r,$tt,$l,18,"0xfff0000f",$l); 206 &R_PERM_OP($l,$tt,$r,12,"0xf0f0f0f0",$r); 207 &rotr($tt , 4); 208 } 209 210
