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 fount 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(PSDevice pDevice, PS802_11Header pMACHeader)
 117 {
 118         unsigned int ii;
 119
 120         for (ii = 0; ii < pDevice->cbDFCB; ii++) {
 121                 if ((pDevice->sRxDFCB[ii].bInUse == TRUE) &&
 122                     (!compare_ether_addr(&(pDevice->sRxDFCB[ii].abyAddr2[0]),
 123                                           &(pMACHeader->abyAddr2[0])))) {
 124                         return ii;
 125                 }
 126         }
 127         return pDevice->cbDFCB;
 128 }
 129
 130 /*
 131  * Description:
 132  *      Insert received fragment packet in Defragment Database
 133  *
 134  * Parameters:
 135  *  In:
 136  *      pDevice     - Pointer to adapter
 137  *      pMACHeader  - 802.11 MAC Header of received packet
 138  *  Out:
 139  *      none
 140  *
 141  * Return Value: index number in Defragment Database
 142  *
 143  */
 144 unsigned int WCTLuInsertDFCB(PSDevice pDevice, PS802_11Header pMACHeader)
 145 {
 146         unsigned int ii;
 147
 148     if (pDevice->cbFreeDFCB == 0)
 149         return(pDevice->cbDFCB);
 150     for (ii = 0; ii < pDevice->cbDFCB; ii++) {
 151         if (pDevice->sRxDFCB[ii].bInUse == FALSE) {
 152             pDevice->cbFreeDFCB--;
 153             pDevice->sRxDFCB[ii].uLifetime = pDevice->dwMaxReceiveLifetime;
 154             pDevice->sRxDFCB[ii].bInUse = TRUE;
 155             pDevice->sRxDFCB[ii].wSequence = (pMACHeader->wSeqCtl >> 4);
 156             pDevice->sRxDFCB[ii].wFragNum = (pMACHeader->wSeqCtl & 0x000F);
 157             memcpy(&(pDevice->sRxDFCB[ii].abyAddr2[0]),
 158                    &(pMACHeader->abyAddr2[0]),
 159                    ETH_ALEN);
 160             return(ii);
 161         }
 162     }
 163     return(pDevice->cbDFCB);
 164 }
 165
 166
 167 /*
 168  * Description:
 169  *      Handle received fragment packet
 170  *
 171  * Parameters:
 172  *  In:
 173  *      pDevice         - Pointer to adapter
 174  *      pMACHeader      - 802.11 MAC Header of received packet
 175  *      cbFrameLength   - Frame length
 176  *      bWEP            - is WEP packet
 177  *  Out:
 178  *      none
 179  *
 180  * Return Value: TRUE if it is valid fragment packet and we have resource to defragment; otherwise FALSE
 181  *
 182  */
 183 BOOL WCTLbHandleFragment(PSDevice pDevice, PS802_11Header pMACHeader,
 184                          unsigned int cbFrameLength, BOOL bWEP, BOOL bExtIV)
 185 {
 186 unsigned int            uHeaderSize;
 187
 188
 189     if (bWEP == TRUE) {
 190         uHeaderSize = 28;
 191         if (bExtIV)
 192         // ExtIV
 193             uHeaderSize +=4;
 194     }
 195     else {
 196         uHeaderSize = 24;
 197     }
 198
 199     if (IS_FIRST_FRAGMENT_PKT(pMACHeader)) {
 200         pDevice->uCurrentDFCBIdx = WCTLuSearchDFCB(pDevice, pMACHeader);
 201         if (pDevice->uCurrentDFCBIdx < pDevice->cbDFCB) {
 202             // duplicate, we must flush previous DCB
 203             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].uLifetime = pDevice->dwMaxReceiveLifetime;
 204             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wSequence = (pMACHeader->wSeqCtl >> 4);
 205             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum = (pMACHeader->wSeqCtl & 0x000F);
 206         }
 207         else {
 208             pDevice->uCurrentDFCBIdx = WCTLuInsertDFCB(pDevice, pMACHeader);
 209             if (pDevice->uCurrentDFCBIdx == pDevice->cbDFCB) {
 210                 return(FALSE);
 211             }
 212         }
 213         // reserve 8 byte to match MAC RX Buffer
 214         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer = (PBYTE) (pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].skb->data + 8);
 215 //        pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer = (PBYTE) (pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].skb->data + 4);
 216         memcpy(pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer, pMACHeader, cbFrameLength);
 217         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength = cbFrameLength;
 218         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer += cbFrameLength;
 219         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum++;
 220         //DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO "First pDevice->uCurrentDFCBIdx= %d\n", pDevice->uCurrentDFCBIdx);
 221         return(FALSE);
 222     }
 223     else {
 224         pDevice->uCurrentDFCBIdx = WCTLuSearchDFCB(pDevice, pMACHeader);
 225         if (pDevice->uCurrentDFCBIdx != pDevice->cbDFCB) {
 226             if ((pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wSequence == (pMACHeader->wSeqCtl >> 4)) &&
 227                 (pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum == (pMACHeader->wSeqCtl & 0x000F)) &&
 228                 ((pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength + cbFrameLength - uHeaderSize) < 2346)) {
 229
 230                 memcpy(pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer, ((PBYTE) (pMACHeader) + uHeaderSize), (cbFrameLength - uHeaderSize));
 231                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength += (cbFrameLength - uHeaderSize);
 232                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer += (cbFrameLength - uHeaderSize);
 233                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum++;
 234                 //DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO "Second pDevice->uCurrentDFCBIdx= %d\n", pDevice->uCurrentDFCBIdx);
 235             }
 236             else {
 237                 // seq error or frag # error flush DFCB
 238                 pDevice->cbFreeDFCB++;
 239                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].bInUse = FALSE;
 240                 return(FALSE);
 241             }
 242         }
 243         else {
 244             return(FALSE);
 245         }
 246         if (IS_LAST_FRAGMENT_PKT(pMACHeader)) {
 247             //enq defragcontrolblock
 248             pDevice->cbFreeDFCB++;
 249             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].bInUse = FALSE;
 250             //DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO "Last pDevice->uCurrentDFCBIdx= %d\n", pDevice->uCurrentDFCBIdx);
 251             return(TRUE);
 252         }
 253         return(FALSE);
 254     }
 255 }
 256
 257