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 # 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 }