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