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 7push(@INC,"perlasm","../../perlasm"); 8require "x86asm.pl"; 9require "cbc.pl"; 10require "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$R="esi"; 21 22&external_label("DES_SPtrans"); 23&DES_encrypt("DES_encrypt1",1); 24&DES_encrypt("DES_encrypt2",0); 25&DES_encrypt3("DES_encrypt3",1); 26&DES_encrypt3("DES_decrypt3",0); 27&cbc("DES_ncbc_encrypt","DES_encrypt1","DES_encrypt1",0,4,5,3,5,-1); 28&cbc("DES_ede3_cbc_encrypt","DES_encrypt3","DES_decrypt3",0,6,7,3,4,5); 29 30&asm_finish(); 31 32sub DES_encrypt 33 { 34 local($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 $trans="ebp"; 44 45 if ($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 # PIC-ification:-) 76 &picmeup($trans,"DES_SPtrans"); 77 #if ($cpp) { &picmeup($trans,"DES_SPtrans"); } 78 #else { &lea($trans,&DWP("DES_SPtrans")); } 79 80 &mov( "ecx", &wparam(1) ); 81 &cmp("ebx","0"); 82 &je(&label("start_decrypt")); 83 84 for ($i=0; $i<16; $i+=2) 85 { 86 &comment(""); 87 &comment("Round $i"); 88 &D_ENCRYPT($i,$L,$R,$i*2,$trans,"eax","ebx","ecx","edx"); 89 90 &comment(""); 91 &comment("Round ".sprintf("%d",$i+1)); 92 &D_ENCRYPT($i+1,$R,$L,($i+1)*2,$trans,"eax","ebx","ecx","edx"); 93 } 94 &jmp(&label("end")); 95 96 &set_label("start_decrypt"); 97 98 for ($i=15; $i>0; $i-=2) 99 { 100 &comment(""); 101 &comment("Round $i"); 102 &D_ENCRYPT(15-$i,$L,$R,$i*2,$trans,"eax","ebx","ecx","edx"); 103 &comment(""); 104 &comment("Round ".sprintf("%d",$i-1)); 105 &D_ENCRYPT(15-$i+1,$R,$L,($i-1)*2,$trans,"eax","ebx","ecx","edx"); 106 } 107 108 &set_label("end"); 109 110 if ($do_ip) 111 { 112 &comment(""); 113 &comment("FP"); 114 &mov("edx",&wparam(0)); 115 &FP_new($L,$R,"eax",3); 116 117 &mov(&DWP(0,"edx","",0),"eax"); 118 &mov(&DWP(4,"edx","",0),$R); 119 } 120 else 121 { 122 &comment(""); 123 &comment("Fixup"); 124 &rotr($L,3); # r 125 &mov("eax",&wparam(0)); 126 &rotr($R,3); # l 127 &mov(&DWP(0,"eax","",0),$L); 128 &mov(&DWP(4,"eax","",0),$R); 129 } 130 131 &pop("ebp"); 132 &pop("ebx"); 133 &pop("edi"); 134 &pop("esi"); 135 &ret(); 136 137 &function_end_B($name); 138 } 139 140sub D_ENCRYPT 141 { 142 local($r,$L,$R,$S,$trans,$u,$tmp1,$tmp2,$t)=@_; 143 144 &mov( $u, &DWP(&n2a($S*4),$tmp2,"",0)); 145 &xor( $tmp1, $tmp1); 146 &mov( $t, &DWP(&n2a(($S+1)*4),$tmp2,"",0)); 147 &xor( $u, $R); 148 &xor( $tmp2, $tmp2); 149 &xor( $t, $R); 150 &and( $u, "0xfcfcfcfc" ); 151 &and( $t, "0xcfcfcfcf" ); 152 &movb( &LB($tmp1), &LB($u) ); 153 &movb( &LB($tmp2), &HB($u) ); 154 &rotr( $t, 4 ); 155 &xor( $L, &DWP(" ",$trans,$tmp1,0)); 156 &movb( &LB($tmp1), &LB($t) ); 157 &xor( $L, &DWP("0x200",$trans,$tmp2,0)); 158 &movb( &LB($tmp2), &HB($t) ); 159 &shr( $u, 16); 160 &xor( $L, &DWP("0x100",$trans,$tmp1,0)); 161 &movb( &LB($tmp1), &HB($u) ); 162 &shr( $t, 16); 163 &xor( $L, &DWP("0x300",$trans,$tmp2,0)); 164 &movb( &LB($tmp2), &HB($t) ); 165 &and( $u, "0xff" ); 166 &and( $t, "0xff" ); 167 &xor( $L, &DWP("0x600",$trans,$tmp1,0)); 168 &xor( $L, &DWP("0x700",$trans,$tmp2,0)); 169 &mov( $tmp2, &wparam(1) ); 170 &xor( $L, &DWP("0x400",$trans,$u,0)); 171 &xor( $L, &DWP("0x500",$trans,$t,0)); 172 } 173 174sub n2a 175 { 176 sprintf("%d",$_[0]); 177 } 178 179# now has a side affect of rotating $a by $shift 180sub R_PERM_OP 181 { 182 local($a,$b,$tt,$shift,$mask,$last)=@_; 183 184 &rotl( $a, $shift ) if ($shift != 0); 185 &mov( $tt, $a ); 186 &xor( $a, $b ); 187 &and( $a, $mask ); 188 # This can never succeed, and besides it is difficult to see what the 189 # idea was - Ben 13 Feb 99 190 if (!$last eq $b) 191 { 192 &xor( $b, $a ); 193 &xor( $tt, $a ); 194 } 195 else 196 { 197 &xor( $tt, $a ); 198 &xor( $b, $a ); 199 } 200 &comment(""); 201 } 202 203sub IP_new 204 { 205 local($l,$r,$tt,$lr)=@_; 206 207 &R_PERM_OP($l,$r,$tt, 4,"0xf0f0f0f0",$l); 208 &R_PERM_OP($r,$tt,$l,20,"0xfff0000f",$l); 209 &R_PERM_OP($l,$tt,$r,14,"0x33333333",$r); 210 &R_PERM_OP($tt,$r,$l,22,"0x03fc03fc",$r); 211 &R_PERM_OP($l,$r,$tt, 9,"0xaaaaaaaa",$r); 212 213 if ($lr != 3) 214 { 215 if (($lr-3) < 0) 216 { &rotr($tt, 3-$lr); } 217 else { &rotl($tt, $lr-3); } 218 } 219 if ($lr != 2) 220 { 221 if (($lr-2) < 0) 222 { &rotr($r, 2-$lr); } 223 else { &rotl($r, $lr-2); } 224 } 225 } 226 227sub FP_new 228 { 229 local($l,$r,$tt,$lr)=@_; 230 231 if ($lr != 2) 232 { 233 if (($lr-2) < 0) 234 { &rotl($r, 2-$lr); } 235 else { &rotr($r, $lr-2); } 236 } 237 if ($lr != 3) 238 { 239 if (($lr-3) < 0) 240 { &rotl($l, 3-$lr); } 241 else { &rotr($l, $lr-3); } 242 } 243 244 &R_PERM_OP($l,$r,$tt, 0,"0xaaaaaaaa",$r); 245 &R_PERM_OP($tt,$r,$l,23,"0x03fc03fc",$r); 246 &R_PERM_OP($l,$r,$tt,10,"0x33333333",$l); 247 &R_PERM_OP($r,$tt,$l,18,"0xfff0000f",$l); 248 &R_PERM_OP($l,$tt,$r,12,"0xf0f0f0f0",$r); 249 &rotr($tt , 4); 250 } 251 252