aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/staging/vt6655/michael.c
blob: 7ea5f7f82f43c259a806addbc882da5f6e8aae54 (plain) (blame)
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
/*
 * Copyright (c) 1996, 2003 VIA Networking Technologies, Inc.
 * All rights reserved.
 *
 * 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 the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 *
 * File: michael.cpp
 *
 * Purpose: The implementation of LIST data structure.
 *
 * Author: Kyle Hsu
 *
 * Date: Sep 4, 2002
 *
 * Functions:
 *      s_dwGetUINT32 - Convert from unsigned char [] to unsigned long in a portable way
 *      s_vPutUINT32 - Convert from unsigned long to unsigned char [] in a portable way
 *      s_vClear - Reset the state to the empty message.
 *      s_vSetKey - Set the key.
 *      MIC_vInit - Set the key.
 *      s_vAppendByte - Append the byte to our word-sized buffer.
 *      MIC_vAppend - call s_vAppendByte.
 *      MIC_vGetMIC - Append the minimum padding and call s_vAppendByte.
 *
 * Revision History:
 *
 */

#include "tmacro.h"
#include "michael.h"

/*---------------------  Static Definitions -------------------------*/

/*---------------------  Static Variables  --------------------------*/

/*---------------------  Static Functions  --------------------------*/
/*
  static unsigned long s_dwGetUINT32(unsigned char *p);         // Get unsigned long from 4 bytes LSByte first
  static void s_vPutUINT32(unsigned char *p, unsigned long val); // Put unsigned long into 4 bytes LSByte first
*/
static void s_vClear(void);                       // Clear the internal message,
// resets the object to the state just after construction.
static void s_vSetKey(unsigned long dwK0, unsigned long dwK1);
static void s_vAppendByte(unsigned char b);            // Add a single byte to the internal message

/*---------------------  Export Variables  --------------------------*/
static unsigned long L, R;           // Current state

static unsigned long K0, K1;         // Key
static unsigned long M;              // Message accumulator (single word)
static unsigned int nBytesInM;      // # bytes in M

/*---------------------  Export Functions  --------------------------*/

/*
  static unsigned long s_dwGetUINT32 (unsigned char *p)
// Convert from unsigned char [] to unsigned long in a portable way
{
unsigned long res = 0;
unsigned int i;
for (i=0; i<4; i++)
{
	res |= (*p++) << (8 * i);
}
return res;
}

static void s_vPutUINT32 (unsigned char *p, unsigned long val)
// Convert from unsigned long to unsigned char [] in a portable way
{
	unsigned int i;
	for (i=0; i<4; i++) {
		*p++ = (unsigned char) (val & 0xff);
		val >>= 8;
	}
}
*/

static void s_vClear(void)
{
	// Reset the state to the empty message.
	L = K0;
	R = K1;
	nBytesInM = 0;
	M = 0;
}

static void s_vSetKey(unsigned long dwK0, unsigned long dwK1)
{
	// Set the key
	K0 = dwK0;
	K1 = dwK1;
	// and reset the message
	s_vClear();
}

static void s_vAppendByte(unsigned char b)
{
	// Append the byte to our word-sized buffer
	M |= b << (8*nBytesInM);
	nBytesInM++;
	// Process the word if it is full.
	if (nBytesInM >= 4) {
		L ^= M;
		R ^= ROL32(L, 17);
		L += R;
		R ^= ((L & 0xff00ff00) >> 8) | ((L & 0x00ff00ff) << 8);
		L += R;
		R ^= ROL32(L, 3);
		L += R;
		R ^= ROR32(L, 2);
		L += R;
		// Clear the buffer
		M = 0;
		nBytesInM = 0;
	}
}

void MIC_vInit(unsigned long dwK0, unsigned long dwK1)
{
	// Set the key
	s_vSetKey(dwK0, dwK1);
}

void MIC_vUnInit(void)
{
	// Wipe the key material
	K0 = 0;
	K1 = 0;

	// And the other fields as well.
	//Note that this sets (L,R) to (K0,K1) which is just fine.
	s_vClear();
}

void MIC_vAppend(unsigned char *src, unsigned int nBytes)
{
	// This is simple
	while (nBytes > 0) {
		s_vAppendByte(*src++);
		nBytes--;
	}
}

void MIC_vGetMIC(unsigned long *pdwL, unsigned long *pdwR)
{
	// Append the minimum padding
	s_vAppendByte(0x5a);
	s_vAppendByte(0);
	s_vAppendByte(0);
	s_vAppendByte(0);
	s_vAppendByte(0);
	// and then zeroes until the length is a multiple of 4
	while (nBytesInM != 0) {
		s_vAppendByte(0);
	}
	// The s_vAppendByte function has already computed the result.
	*pdwL = L;
	*pdwR = R;
	// Reset to the empty message.
	s_vClear();
}