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