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
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
|
/*
* 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: wctl.c
*
* Purpose: handle WMAC duplicate filter & defragment
*
* Author: Jerry Chen
*
* Date: Jun. 27, 2002
*
* Functions:
* WCTLbIsDuplicate - Test if duplicate packet
* WCTLuSearchDFCB - Search DeFragment Control Database
* WCTLuInsertDFCB - Insert DeFragment Control Database
* WCTLbHandleFragment - Handle received fragment packet
*
* Revision History:
*
*/
#include "wctl.h"
#include "device.h"
#include "card.h"
/*--------------------- Static Definitions -------------------------*/
/*--------------------- Static Classes ----------------------------*/
/*--------------------- Static Variables --------------------------*/
/*--------------------- Static Functions --------------------------*/
/*--------------------- Export Variables --------------------------*/
/*
* Description:
* Scan Rx cache. Return true if packet is duplicate, else
* inserts in receive cache and returns false.
*
* Parameters:
* In:
* pCache - Receive packets history
* pMACHeader - 802.11 MAC Header of received packet
* Out:
* none
*
* Return Value: true if packet duplicate; otherwise false
*
*/
bool WCTLbIsDuplicate(PSCache pCache, PS802_11Header pMACHeader)
{
unsigned int uIndex;
unsigned int ii;
PSCacheEntry pCacheEntry;
if (IS_FC_RETRY(pMACHeader)) {
uIndex = pCache->uInPtr;
for (ii = 0; ii < DUPLICATE_RX_CACHE_LENGTH; ii++) {
pCacheEntry = &(pCache->asCacheEntry[uIndex]);
if ((pCacheEntry->wFmSequence == pMACHeader->wSeqCtl) &&
ether_addr_equal(pCacheEntry->abyAddr2,
pMACHeader->abyAddr2)) {
/* Duplicate match */
return true;
}
ADD_ONE_WITH_WRAP_AROUND(uIndex, DUPLICATE_RX_CACHE_LENGTH);
}
}
/* Not fount in cache - insert */
pCacheEntry = &pCache->asCacheEntry[pCache->uInPtr];
pCacheEntry->wFmSequence = pMACHeader->wSeqCtl;
memcpy(&(pCacheEntry->abyAddr2[0]), &(pMACHeader->abyAddr2[0]), ETH_ALEN);
ADD_ONE_WITH_WRAP_AROUND(pCache->uInPtr, DUPLICATE_RX_CACHE_LENGTH);
return false;
}
/*
* Description:
* Found if sequence number of received fragment packet in Defragment Database
*
* Parameters:
* In:
* pDevice - Pointer to adapter
* pMACHeader - 802.11 MAC Header of received packet
* Out:
* none
*
* Return Value: index number in Defragment Database
*
*/
unsigned int WCTLuSearchDFCB(struct vnt_private *pDevice,
PS802_11Header pMACHeader)
{
unsigned int ii;
for (ii = 0; ii < pDevice->cbDFCB; ii++) {
if (pDevice->sRxDFCB[ii].bInUse &&
ether_addr_equal(pDevice->sRxDFCB[ii].abyAddr2,
pMACHeader->abyAddr2)) {
return ii;
}
}
return pDevice->cbDFCB;
}
/*
* Description:
* Insert received fragment packet in Defragment Database
*
* Parameters:
* In:
* pDevice - Pointer to adapter
* pMACHeader - 802.11 MAC Header of received packet
* Out:
* none
*
* Return Value: index number in Defragment Database
*
*/
unsigned int WCTLuInsertDFCB(struct vnt_private *pDevice, PS802_11Header pMACHeader)
{
unsigned int ii;
if (pDevice->cbFreeDFCB == 0)
return pDevice->cbDFCB;
for (ii = 0; ii < pDevice->cbDFCB; ii++) {
if (!pDevice->sRxDFCB[ii].bInUse) {
pDevice->cbFreeDFCB--;
pDevice->sRxDFCB[ii].uLifetime = pDevice->dwMaxReceiveLifetime;
pDevice->sRxDFCB[ii].bInUse = true;
pDevice->sRxDFCB[ii].wSequence = (pMACHeader->wSeqCtl >> 4);
pDevice->sRxDFCB[ii].wFragNum = (pMACHeader->wSeqCtl & 0x000F);
memcpy(&(pDevice->sRxDFCB[ii].abyAddr2[0]), &(pMACHeader->abyAddr2[0]), ETH_ALEN);
return ii;
}
}
return pDevice->cbDFCB;
}
/*
* Description:
* Handle received fragment packet
*
* Parameters:
* In:
* pDevice - Pointer to adapter
* pMACHeader - 802.11 MAC Header of received packet
* cbFrameLength - Frame length
* bWEP - is WEP packet
* Out:
* none
*
* Return Value: true if it is valid fragment packet and we have resource to defragment; otherwise false
*
*/
bool WCTLbHandleFragment(struct vnt_private *pDevice, PS802_11Header pMACHeader,
unsigned int cbFrameLength, bool bWEP, bool bExtIV)
{
unsigned int uHeaderSize;
if (bWEP) {
uHeaderSize = 28;
if (bExtIV)
// ExtIV
uHeaderSize += 4;
} else {
uHeaderSize = 24;
}
if (IS_FIRST_FRAGMENT_PKT(pMACHeader)) {
pDevice->uCurrentDFCBIdx = WCTLuSearchDFCB(pDevice, pMACHeader);
if (pDevice->uCurrentDFCBIdx < pDevice->cbDFCB) {
// duplicate, we must flush previous DCB
pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].uLifetime = pDevice->dwMaxReceiveLifetime;
pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wSequence = (pMACHeader->wSeqCtl >> 4);
pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum = (pMACHeader->wSeqCtl & 0x000F);
} else {
pDevice->uCurrentDFCBIdx = WCTLuInsertDFCB(pDevice, pMACHeader);
if (pDevice->uCurrentDFCBIdx == pDevice->cbDFCB)
return false;
}
// reserve 4 byte to match MAC RX Buffer
pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer = (unsigned char *)(pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].skb->data + 4);
memcpy(pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer, pMACHeader, cbFrameLength);
pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength = cbFrameLength;
pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer += cbFrameLength;
pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum++;
return false;
} else {
pDevice->uCurrentDFCBIdx = WCTLuSearchDFCB(pDevice, pMACHeader);
if (pDevice->uCurrentDFCBIdx != pDevice->cbDFCB) {
if ((pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wSequence == (pMACHeader->wSeqCtl >> 4)) &&
(pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum == (pMACHeader->wSeqCtl & 0x000F)) &&
((pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength + cbFrameLength - uHeaderSize) < 2346)) {
memcpy(pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer, ((unsigned char *)(pMACHeader) + uHeaderSize), (cbFrameLength - uHeaderSize));
pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength += (cbFrameLength - uHeaderSize);
pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer += (cbFrameLength - uHeaderSize);
pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum++;
} else {
// seq error or frag # error flush DFCB
pDevice->cbFreeDFCB++;
pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].bInUse = false;
return false;
}
} else {
return false;
}
if (IS_LAST_FRAGMENT_PKT(pMACHeader)) {
//enq defragcontrolblock
pDevice->cbFreeDFCB++;
pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].bInUse = false;
return true;
}
return false;
}
}
|
