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
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
|
/*
mdfour.c
An implementation of MD4 designed for use in the samba SMB
authentication protocol
Copyright (C) 1997-1998 Andrew Tridgell
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to:
Free Software Foundation, Inc.
59 Temple Place - Suite 330
Boston, MA 02111-1307, USA
$Id: mdfour.c,v 1.1 2002/08/23 22:03:27 abster Exp $
*/
#include "q_shared.h"
#include "qcommon.h"
struct mdfour {
uint32_t A, B, C, D;
uint32_t totalN;
};
/* NOTE: This code makes no attempt to be fast!
It assumes that an int is at least 32 bits long
*/
static struct mdfour *m;
#define F(X,Y,Z) (((X)&(Y)) | ((~(X))&(Z)))
#define G(X,Y,Z) (((X)&(Y)) | ((X)&(Z)) | ((Y)&(Z)))
#define H(X,Y,Z) ((X)^(Y)^(Z))
#define lshift(x,s) (((x)<<(s)) | ((x)>>(32-(s))))
#define ROUND1(a,b,c,d,k,s) a = lshift(a + F(b,c,d) + X[k], s)
#define ROUND2(a,b,c,d,k,s) a = lshift(a + G(b,c,d) + X[k] + 0x5A827999,s)
#define ROUND3(a,b,c,d,k,s) a = lshift(a + H(b,c,d) + X[k] + 0x6ED9EBA1,s)
/* this applies md4 to 64 byte chunks */
static void mdfour64(uint32_t *M)
{
int j;
uint32_t AA, BB, CC, DD;
uint32_t X[16];
uint32_t A,B,C,D;
for (j=0;j<16;j++)
X[j] = M[j];
A = m->A; B = m->B; C = m->C; D = m->D;
AA = A; BB = B; CC = C; DD = D;
ROUND1(A,B,C,D, 0, 3); ROUND1(D,A,B,C, 1, 7);
ROUND1(C,D,A,B, 2, 11); ROUND1(B,C,D,A, 3, 19);
ROUND1(A,B,C,D, 4, 3); ROUND1(D,A,B,C, 5, 7);
ROUND1(C,D,A,B, 6, 11); ROUND1(B,C,D,A, 7, 19);
ROUND1(A,B,C,D, 8, 3); ROUND1(D,A,B,C, 9, 7);
ROUND1(C,D,A,B, 10, 11); ROUND1(B,C,D,A, 11, 19);
ROUND1(A,B,C,D, 12, 3); ROUND1(D,A,B,C, 13, 7);
ROUND1(C,D,A,B, 14, 11); ROUND1(B,C,D,A, 15, 19);
ROUND2(A,B,C,D, 0, 3); ROUND2(D,A,B,C, 4, 5);
ROUND2(C,D,A,B, 8, 9); ROUND2(B,C,D,A, 12, 13);
ROUND2(A,B,C,D, 1, 3); ROUND2(D,A,B,C, 5, 5);
ROUND2(C,D,A,B, 9, 9); ROUND2(B,C,D,A, 13, 13);
ROUND2(A,B,C,D, 2, 3); ROUND2(D,A,B,C, 6, 5);
ROUND2(C,D,A,B, 10, 9); ROUND2(B,C,D,A, 14, 13);
ROUND2(A,B,C,D, 3, 3); ROUND2(D,A,B,C, 7, 5);
ROUND2(C,D,A,B, 11, 9); ROUND2(B,C,D,A, 15, 13);
ROUND3(A,B,C,D, 0, 3); ROUND3(D,A,B,C, 8, 9);
ROUND3(C,D,A,B, 4, 11); ROUND3(B,C,D,A, 12, 15);
ROUND3(A,B,C,D, 2, 3); ROUND3(D,A,B,C, 10, 9);
ROUND3(C,D,A,B, 6, 11); ROUND3(B,C,D,A, 14, 15);
ROUND3(A,B,C,D, 1, 3); ROUND3(D,A,B,C, 9, 9);
ROUND3(C,D,A,B, 5, 11); ROUND3(B,C,D,A, 13, 15);
ROUND3(A,B,C,D, 3, 3); ROUND3(D,A,B,C, 11, 9);
ROUND3(C,D,A,B, 7, 11); ROUND3(B,C,D,A, 15, 15);
A += AA; B += BB; C += CC; D += DD;
for (j=0;j<16;j++)
X[j] = 0;
m->A = A; m->B = B; m->C = C; m->D = D;
}
static void copy64(uint32_t *M, byte *in)
{
int i;
for (i=0;i<16;i++)
M[i] = (in[i*4+3]<<24) | (in[i*4+2]<<16) |
(in[i*4+1]<<8) | (in[i*4+0]<<0);
}
static void copy4(byte *out,uint32_t x)
{
out[0] = x&0xFF;
out[1] = (x>>8)&0xFF;
out[2] = (x>>16)&0xFF;
out[3] = (x>>24)&0xFF;
}
void mdfour_begin(struct mdfour *md)
{
md->A = 0x67452301;
md->B = 0xefcdab89;
md->C = 0x98badcfe;
md->D = 0x10325476;
md->totalN = 0;
}
static void mdfour_tail(byte *in, int n)
{
byte buf[128];
uint32_t M[16];
uint32_t b;
m->totalN += n;
b = m->totalN * 8;
Com_Memset(buf, 0, 128);
if (n) Com_Memcpy(buf, in, n);
buf[n] = 0x80;
if (n <= 55) {
copy4(buf+56, b);
copy64(M, buf);
mdfour64(M);
} else {
copy4(buf+120, b);
copy64(M, buf);
mdfour64(M);
copy64(M, buf+64);
mdfour64(M);
}
}
static void mdfour_update(struct mdfour *md, byte *in, int n)
{
uint32_t M[16];
m = md;
if (n == 0) mdfour_tail(in, n);
while (n >= 64) {
copy64(M, in);
mdfour64(M);
in += 64;
n -= 64;
m->totalN += 64;
}
mdfour_tail(in, n);
}
static void mdfour_result(struct mdfour *md, byte *out)
{
m = md;
copy4(out, m->A);
copy4(out+4, m->B);
copy4(out+8, m->C);
copy4(out+12, m->D);
}
static void mdfour(byte *out, byte *in, int n)
{
struct mdfour md;
mdfour_begin(&md);
mdfour_update(&md, in, n);
mdfour_result(&md, out);
}
//===================================================================
unsigned Com_BlockChecksum (const void *buffer, int length)
{
int digest[4];
unsigned val;
mdfour( (byte *)digest, (byte *)buffer, length );
val = digest[0] ^ digest[1] ^ digest[2] ^ digest[3];
return val;
}
|
