drivers/staging/vt6656/wctl.c

   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  * File: wctl.c
  20  *
  21  * Purpose: handle WMAC duplicate filter & defragment
  22  *
  23  * Author: Jerry Chen
  24  *
  25  * Date: Jun. 27, 2002
  26  *
  27  * Functions:
  28  *      WCTLbIsDuplicate - Test if duplicate packet
  29  *      WCTLuSearchDFCB - Search DeFragment Control Database
  30  *      WCTLuInsertDFCB - Insert DeFragment Control Database
  31  *      WCTLbHandleFragment - Handle received fragment packet
  32  *
  33  * Revision History:
  34  *
  35  */
  36
  37 #include "wctl.h"
  38 #include "device.h"
  39 #include "card.h"
  40 #include "tmacro.h"
  41
  42 /*---------------------  Static Definitions -------------------------*/
  43
  44 /*---------------------  Static Classes  ----------------------------*/
  45
  46 /*---------------------  Static Variables  --------------------------*/
  47 // static int          msglevel                =MSG_LEVEL_INFO;
  48 /*---------------------  Static Functions  --------------------------*/
  49
  50 /*---------------------  Export Variables  --------------------------*/
  51
  52
  53
  54 /*
  55  * Description:
  56  *      Scan Rx cache.  Return true if packet is duplicate, else
  57  *      inserts in receive cache and returns false.
  58  *
  59  * Parameters:
  60  *  In:
  61  *      pCache      - Receive packets history
  62  *      pMACHeader  - 802.11 MAC Header of received packet
  63  *  Out:
  64  *      none
  65  *
  66  * Return Value: true if packet duplicate; otherwise false
  67  *
  68  */
  69
  70 bool WCTLbIsDuplicate (PSCache pCache, PS802_11Header pMACHeader)
  71 {
  72     unsigned int            uIndex;
  73     unsigned int            ii;
  74     PSCacheEntry    pCacheEntry;
  75
  76     if (IS_FC_RETRY(pMACHeader)) {
  77
  78         uIndex = pCache->uInPtr;
  79         for (ii = 0; ii < DUPLICATE_RX_CACHE_LENGTH; ii++) {
  80             pCacheEntry = &(pCache->asCacheEntry[uIndex]);
  81             if ((pCacheEntry->wFmSequence == pMACHeader->wSeqCtl) &&
  82                 (!compare_ether_addr(&(pCacheEntry->abyAddr2[0]),
  83                                      &(pMACHeader->abyAddr2[0]))) &&
  84                 (LOBYTE(pCacheEntry->wFrameCtl) == LOBYTE(pMACHeader->wFrameCtl))
  85                 ) {
  86                 /* Duplicate match */
  87                 return true;
  88             }
  89             ADD_ONE_WITH_WRAP_AROUND(uIndex, DUPLICATE_RX_CACHE_LENGTH);
  90         }
  91     }
  92     /* Not found in cache - insert */
  93     pCacheEntry = &pCache->asCacheEntry[pCache->uInPtr];
  94     pCacheEntry->wFmSequence = pMACHeader->wSeqCtl;
  95     memcpy(&(pCacheEntry->abyAddr2[0]), &(pMACHeader->abyAddr2[0]), ETH_ALEN);
  96     pCacheEntry->wFrameCtl = pMACHeader->wFrameCtl;
  97     ADD_ONE_WITH_WRAP_AROUND(pCache->uInPtr, DUPLICATE_RX_CACHE_LENGTH);
  98     return false;
  99 }
 100
 101 /*
 102  * Description:
 103  *      Found if sequence number of received fragment packet in Defragment Database
 104  *
 105  * Parameters:
 106  *  In:
 107  *      pDevice     - Pointer to adapter
 108  *      pMACHeader  - 802.11 MAC Header of received packet
 109  *  Out:
 110  *      none
 111  *
 112  * Return Value: index number in Defragment Database
 113  *
 114  */
 115
 116 unsigned int WCTLuSearchDFCB(struct vnt_private *pDevice,
 117         PS802_11Header pMACHeader)
 118 {
 119         unsigned int ii;
 120
 121         for (ii = 0; ii < pDevice->cbDFCB; ii++) {
 122                 if ((pDevice->sRxDFCB[ii].bInUse == true) &&
 123                     (!compare_ether_addr(&(pDevice->sRxDFCB[ii].abyAddr2[0]),
 124                                           &(pMACHeader->abyAddr2[0])))) {
 125                         return ii;
 126                 }
 127         }
 128         return pDevice->cbDFCB;
 129 }
 130
 131 /*
 132  * Description:
 133  *      Insert received fragment packet in Defragment Database
 134  *
 135  * Parameters:
 136  *  In:
 137  *      pDevice     - Pointer to adapter
 138  *      pMACHeader  - 802.11 MAC Header of received packet
 139  *  Out:
 140  *      none
 141  *
 142  * Return Value: index number in Defragment Database
 143  *
 144  */
 145 unsigned int WCTLuInsertDFCB(struct vnt_private *pDevice,
 146         PS802_11Header pMACHeader)
 147 {
 148         unsigned int ii;
 149
 150     if (pDevice->cbFreeDFCB == 0)
 151         return(pDevice->cbDFCB);
 152     for (ii = 0; ii < pDevice->cbDFCB; ii++) {
 153         if (pDevice->sRxDFCB[ii].bInUse == false) {
 154             pDevice->cbFreeDFCB--;
 155             pDevice->sRxDFCB[ii].uLifetime = pDevice->dwMaxReceiveLifetime;
 156             pDevice->sRxDFCB[ii].bInUse = true;
 157             pDevice->sRxDFCB[ii].wSequence = (pMACHeader->wSeqCtl >> 4);
 158             pDevice->sRxDFCB[ii].wFragNum = (pMACHeader->wSeqCtl & 0x000F);
 159             memcpy(&(pDevice->sRxDFCB[ii].abyAddr2[0]),
 160                    &(pMACHeader->abyAddr2[0]),
 161                    ETH_ALEN);
 162             return(ii);
 163         }
 164     }
 165     return(pDevice->cbDFCB);
 166 }
 167
 168
 169 /*
 170  * Description:
 171  *      Handle received fragment packet
 172  *
 173  * Parameters:
 174  *  In:
 175  *      pDevice         - Pointer to adapter
 176  *      pMACHeader      - 802.11 MAC Header of received packet
 177  *      cbFrameLength   - Frame length
 178  *      bWEP            - is WEP packet
 179  *  Out:
 180  *      none
 181  *
 182  * Return Value: true if it is valid fragment packet and we have resource to defragment; otherwise false
 183  *
 184  */
 185 bool WCTLbHandleFragment(struct vnt_private *pDevice, PS802_11Header pMACHeader,
 186         unsigned int cbFrameLength, bool bWEP, bool bExtIV)
 187 {
 188         unsigned int uHeaderSize;
 189
 190
 191     if (bWEP == true) {
 192         uHeaderSize = 28;
 193         if (bExtIV)
 194         // ExtIV
 195             uHeaderSize +=4;
 196     }
 197     else {
 198         uHeaderSize = 24;
 199     }
 200
 201     if (IS_FIRST_FRAGMENT_PKT(pMACHeader)) {
 202         pDevice->uCurrentDFCBIdx = WCTLuSearchDFCB(pDevice, pMACHeader);
 203         if (pDevice->uCurrentDFCBIdx < pDevice->cbDFCB) {
 204             // duplicate, we must flush previous DCB
 205             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].uLifetime = pDevice->dwMaxReceiveLifetime;
 206             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wSequence = (pMACHeader->wSeqCtl >> 4);
 207             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum = (pMACHeader->wSeqCtl & 0x000F);
 208         }
 209         else {
 210             pDevice->uCurrentDFCBIdx = WCTLuInsertDFCB(pDevice, pMACHeader);
 211             if (pDevice->uCurrentDFCBIdx == pDevice->cbDFCB) {
 212                 return(false);
 213             }
 214         }
 215         // reserve 8 byte to match MAC RX Buffer
 216         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer = (PBYTE) (pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].skb->data + 8);
 217 //        pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer = (PBYTE) (pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].skb->data + 4);
 218         memcpy(pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer, pMACHeader, cbFrameLength);
 219         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength = cbFrameLength;
 220         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer += cbFrameLength;
 221         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum++;
 222         //DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO "First pDevice->uCurrentDFCBIdx= %d\n", pDevice->uCurrentDFCBIdx);
 223         return(false);
 224     }
 225     else {
 226         pDevice->uCurrentDFCBIdx = WCTLuSearchDFCB(pDevice, pMACHeader);
 227         if (pDevice->uCurrentDFCBIdx != pDevice->cbDFCB) {
 228             if ((pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wSequence == (pMACHeader->wSeqCtl >> 4)) &&
 229                 (pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum == (pMACHeader->wSeqCtl & 0x000F)) &&
 230                 ((pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength + cbFrameLength - uHeaderSize) < 2346)) {
 231
 232                 memcpy(pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer, ((PBYTE) (pMACHeader) + uHeaderSize), (cbFrameLength - uHeaderSize));
 233                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength += (cbFrameLength - uHeaderSize);
 234                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer += (cbFrameLength - uHeaderSize);
 235                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum++;
 236                 //DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO "Second pDevice->uCurrentDFCBIdx= %d\n", pDevice->uCurrentDFCBIdx);
 237             }
 238             else {
 239                 // seq error or frag # error flush DFCB
 240                 pDevice->cbFreeDFCB++;
 241                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].bInUse = false;
 242                 return(false);
 243             }
 244         }
 245         else {
 246             return(false);
 247         }
 248         if (IS_LAST_FRAGMENT_PKT(pMACHeader)) {
 249             //enq defragcontrolblock
 250             pDevice->cbFreeDFCB++;
 251             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].bInUse = false;
 252             //DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO "Last pDevice->uCurrentDFCBIdx= %d\n", pDevice->uCurrentDFCBIdx);
 253             return(true);
 254         }
 255         return(false);
 256     }
 257 }
 258
 259