1 /*
2 * Copyright (c) 1996, 2003 VIA Networking Technologies, Inc.
3 * All rights reserved.
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 *
20 * File: michael.cpp
21 *
22 * Purpose: The implementation of LIST data structure.
23 *
24 * Author: Kyle Hsu
25 *
26 * Date: Sep 4, 2002
27 *
28 * Functions:
29 * s_dwGetUINT32 - Convert from unsigned char [] to unsigned long in a portable way
30 * s_vPutUINT32 - Convert from unsigned long to unsigned char [] in a portable way
31 * s_vClear - Reset the state to the empty message.
32 * s_vSetKey - Set the key.
33 * MIC_vInit - Set the key.
34 * s_vAppendByte - Append the byte to our word-sized buffer.
35 * MIC_vAppend - call s_vAppendByte.
36 * MIC_vGetMIC - Append the minimum padding and call s_vAppendByte.
37 *
38 * Revision History:
39 *
40 */
41
42 #include "tmacro.h"
43 #include "michael.h"
44
45 /*--------------------- Static Definitions -------------------------*/
46
47 /*--------------------- Static Variables --------------------------*/
48
49 /*--------------------- Static Functions --------------------------*/
50 /*
51 static unsigned long s_dwGetUINT32(unsigned char *p); // Get unsigned long from 4 bytes LSByte first
52 static void s_vPutUINT32(unsigned char *p, unsigned long val); // Put unsigned long into 4 bytes LSByte first
53 */
54 static void s_vClear(void); // Clear the internal message,
55 // resets the object to the state just after construction.
56 static void s_vSetKey(unsigned long dwK0, unsigned long dwK1);
57 static void s_vAppendByte(unsigned char b); // Add a single byte to the internal message
58
59 /*--------------------- Export Variables --------------------------*/
60 static unsigned long L, R; // Current state
61
62 static unsigned long K0, K1; // Key
63 static unsigned long M; // Message accumulator (single word)
64 static unsigned int nBytesInM; // # bytes in M
65
66 /*--------------------- Export Functions --------------------------*/
67
68 /*
69 static unsigned long s_dwGetUINT32 (unsigned char *p)
70 // Convert from unsigned char [] to unsigned long in a portable way
71 {
72 unsigned long res = 0;
73 unsigned int i;
74 for (i=0; i<4; i++)
75 {
76 res |= (*p++) << (8 * i);
77 }
78 return res;
79 }
80
81 static void s_vPutUINT32 (unsigned char *p, unsigned long val)
82 // Convert from unsigned long to unsigned char [] in a portable way
83 {
84 unsigned int i;
85 for (i=0; i<4; i++) {
86 *p++ = (unsigned char) (val & 0xff);
87 val >>= 8;
88 }
89 }
90 */
91
s_vClear(void)92 static void s_vClear(void)
93 {
94 // Reset the state to the empty message.
95 L = K0;
96 R = K1;
97 nBytesInM = 0;
98 M = 0;
99 }
100
s_vSetKey(unsigned long dwK0,unsigned long dwK1)101 static void s_vSetKey(unsigned long dwK0, unsigned long dwK1)
102 {
103 // Set the key
104 K0 = dwK0;
105 K1 = dwK1;
106 // and reset the message
107 s_vClear();
108 }
109
s_vAppendByte(unsigned char b)110 static void s_vAppendByte(unsigned char b)
111 {
112 // Append the byte to our word-sized buffer
113 M |= b << (8*nBytesInM);
114 nBytesInM++;
115 // Process the word if it is full.
116 if (nBytesInM >= 4) {
117 L ^= M;
118 R ^= ROL32(L, 17);
119 L += R;
120 R ^= ((L & 0xff00ff00) >> 8) | ((L & 0x00ff00ff) << 8);
121 L += R;
122 R ^= ROL32(L, 3);
123 L += R;
124 R ^= ROR32(L, 2);
125 L += R;
126 // Clear the buffer
127 M = 0;
128 nBytesInM = 0;
129 }
130 }
131
MIC_vInit(unsigned long dwK0,unsigned long dwK1)132 void MIC_vInit(unsigned long dwK0, unsigned long dwK1)
133 {
134 // Set the key
135 s_vSetKey(dwK0, dwK1);
136 }
137
MIC_vUnInit(void)138 void MIC_vUnInit(void)
139 {
140 // Wipe the key material
141 K0 = 0;
142 K1 = 0;
143
144 // And the other fields as well.
145 //Note that this sets (L,R) to (K0,K1) which is just fine.
146 s_vClear();
147 }
148
MIC_vAppend(unsigned char * src,unsigned int nBytes)149 void MIC_vAppend(unsigned char *src, unsigned int nBytes)
150 {
151 // This is simple
152 while (nBytes > 0) {
153 s_vAppendByte(*src++);
154 nBytes--;
155 }
156 }
157
MIC_vGetMIC(unsigned long * pdwL,unsigned long * pdwR)158 void MIC_vGetMIC(unsigned long *pdwL, unsigned long *pdwR)
159 {
160 // Append the minimum padding
161 s_vAppendByte(0x5a);
162 s_vAppendByte(0);
163 s_vAppendByte(0);
164 s_vAppendByte(0);
165 s_vAppendByte(0);
166 // and then zeroes until the length is a multiple of 4
167 while (nBytesInM != 0) {
168 s_vAppendByte(0);
169 }
170 // The s_vAppendByte function has already computed the result.
171 *pdwL = L;
172 *pdwR = R;
173 // Reset to the empty message.
174 s_vClear();
175 }
176