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 u8[] to u32 in a portable way
 30 *      s_vPutUINT32 - Convert from u32 to u8[] 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/*
 46 * static u32 s_dwGetUINT32(u8 * p);         Get u32 from
 47 *							4 bytes LSByte first
 48 * static void s_vPutUINT32(u8* p, u32 val); Put u32 into
 49 *							4 bytes LSByte first
 50 */
 51static void s_vClear(void);		/* Clear the internal message,
 52					 * resets the object to the
 53					 * state just after construction. */
 54static void s_vSetKey(u32 dwK0, u32 dwK1);
 55static void s_vAppendByte(u8 b);	/* Add a single byte to the internal
 56					 * message */
 57
 58static u32  L, R;		/* Current state */
 59static u32  K0, K1;		/* Key */
 60static u32  M;		/* Message accumulator (single word) */
 61static unsigned int   nBytesInM;	/* # bytes in M */
 62
 63/*
 64static u32 s_dwGetUINT32 (u8 * p)
 65// Convert from u8[] to u32 in a portable way
 66{
 67	u32 res = 0;
 68	unsigned int i;
 69	for (i = 0; i < 4; i++)
 70		res |= (*p++) << (8*i);
 71	return res;
 72}
 73
 74static void s_vPutUINT32(u8 *p, u32 val)
 75// Convert from u32 to u8[] in a portable way
 76{
 77	unsigned int i;
 78	for (i = 0; i < 4; i++) {
 79		*p++ = (u8) (val & 0xff);
 80		val >>= 8;
 81	}
 82}
 83*/
 84
 85static void s_vClear(void)
 86{
 87	/* Reset the state to the empty message. */
 88	L = K0;
 89	R = K1;
 90	nBytesInM = 0;
 91	M = 0;
 92}
 93
 94static void s_vSetKey(u32 dwK0, u32 dwK1)
 95{
 96	/* Set the key */
 97	K0 = dwK0;
 98	K1 = dwK1;
 99	/* and reset the message */
100	s_vClear();
101}
102
103static void s_vAppendByte(u8 b)
104{
105	/* Append the byte to our word-sized buffer */
106	M |= b << (8*nBytesInM);
107	nBytesInM++;
108	/* Process the word if it is full. */
109	if (nBytesInM >= 4) {
110		L ^= M;
111		R ^= ROL32(L, 17);
112		L += R;
113		R ^= ((L & 0xff00ff00) >> 8) | ((L & 0x00ff00ff) << 8);
114		L += R;
115		R ^= ROL32(L, 3);
116		L += R;
117		R ^= ROR32(L, 2);
118		L += R;
119		/* Clear the buffer */
120		M = 0;
121		nBytesInM = 0;
122	}
123}
124
125void MIC_vInit(u32 dwK0, u32 dwK1)
126{
127	/* Set the key */
128	s_vSetKey(dwK0, dwK1);
129}
130
131void MIC_vUnInit(void)
132{
133	/* Wipe the key material */
134	K0 = 0;
135	K1 = 0;
136
137	/* And the other fields as well. */
138	/* Note that this sets (L,R) to (K0,K1) which is just fine. */
139	s_vClear();
140}
141
142void MIC_vAppend(u8 * src, unsigned int nBytes)
143{
144    /* This is simple */
145	while (nBytes > 0) {
146		s_vAppendByte(*src++);
147		nBytes--;
148	}
149}
150
151void MIC_vGetMIC(u32 * pdwL, u32 * pdwR)
152{
153	/* Append the minimum padding */
154	s_vAppendByte(0x5a);
155	s_vAppendByte(0);
156	s_vAppendByte(0);
157	s_vAppendByte(0);
158	s_vAppendByte(0);
159	/* and then zeroes until the length is a multiple of 4 */
160	while (nBytesInM != 0)
161		s_vAppendByte(0);
162	/* The s_vAppendByte function has already computed the result. */
163	*pdwL = L;
164	*pdwR = R;
165	/* Reset to the empty message. */
166	s_vClear();
167}