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 int          msglevel                =MSG_LEVEL_INFO;
  43
  44 /*
  45  * Description:
  46  *      Scan Rx cache.  Return true if packet is duplicate, else
  47  *      inserts in receive cache and returns false.
  48  *
  49  * Parameters:
  50  *  In:
  51  *      pCache      - Receive packets history
  52  *      pMACHeader  - 802.11 MAC Header of received packet
  53  *  Out:
  54  *      none
  55  *
  56  * Return Value: true if packet duplicate; otherwise false
  57  *
  58  */
  59
  60 bool WCTLbIsDuplicate (PSCache pCache, struct ieee80211_hdr *pMACHeader)
  61 {
  62     unsigned int            uIndex;
  63     unsigned int            ii;
  64     PSCacheEntry    pCacheEntry;
  65
  66     if (IS_FC_RETRY(pMACHeader)) {
  67
  68         uIndex = pCache->uInPtr;
  69         for (ii = 0; ii < DUPLICATE_RX_CACHE_LENGTH; ii++) {
  70             pCacheEntry = &(pCache->asCacheEntry[uIndex]);
  71             if ((pCacheEntry->wFmSequence == pMACHeader->seq_ctrl) &&
  72                 (!compare_ether_addr(&(pCacheEntry->abyAddr2[0]),
  73                                      &(pMACHeader->addr2[0]))) &&
  74                 (LOBYTE(pCacheEntry->wFrameCtl) == LOBYTE(pMACHeader->frame_control))
  75                 ) {
  76                 /* Duplicate match */
  77                 return true;
  78             }
  79             ADD_ONE_WITH_WRAP_AROUND(uIndex, DUPLICATE_RX_CACHE_LENGTH);
  80         }
  81     }
  82     /* Not found in cache - insert */
  83     pCacheEntry = &pCache->asCacheEntry[pCache->uInPtr];
  84     pCacheEntry->wFmSequence = pMACHeader->seq_ctrl;
  85     memcpy(&(pCacheEntry->abyAddr2[0]), &(pMACHeader->addr2[0]), ETH_ALEN);
  86     pCacheEntry->wFrameCtl = pMACHeader->frame_control;
  87     ADD_ONE_WITH_WRAP_AROUND(pCache->uInPtr, DUPLICATE_RX_CACHE_LENGTH);
  88     return false;
  89 }
  90
  91 /*
  92  * Description:
  93  *      Found if sequence number of received fragment packet in Defragment Database
  94  *
  95  * Parameters:
  96  *  In:
  97  *      pDevice     - Pointer to adapter
  98  *      pMACHeader  - 802.11 MAC Header of received packet
  99  *  Out:
 100  *      none
 101  *
 102  * Return Value: index number in Defragment Database
 103  *
 104  */
 105
 106 unsigned int WCTLuSearchDFCB(struct vnt_private *pDevice,
 107                              struct ieee80211_hdr *pMACHeader)
 108 {
 109         unsigned int ii;
 110
 111         for (ii = 0; ii < pDevice->cbDFCB; ii++) {
 112                 if ((pDevice->sRxDFCB[ii].bInUse == true) &&
 113                     (!compare_ether_addr(&(pDevice->sRxDFCB[ii].abyAddr2[0]),
 114                                           &(pMACHeader->addr2[0])))) {
 115                         return ii;
 116                 }
 117         }
 118         return pDevice->cbDFCB;
 119 }
 120
 121 /*
 122  * Description:
 123  *      Insert received fragment packet in Defragment Database
 124  *
 125  * Parameters:
 126  *  In:
 127  *      pDevice     - Pointer to adapter
 128  *      pMACHeader  - 802.11 MAC Header of received packet
 129  *  Out:
 130  *      none
 131  *
 132  * Return Value: index number in Defragment Database
 133  *
 134  */
 135 unsigned int WCTLuInsertDFCB(struct vnt_private *pDevice,
 136                              struct ieee80211_hdr *pMACHeader)
 137 {
 138         unsigned int ii;
 139
 140     if (pDevice->cbFreeDFCB == 0)
 141         return(pDevice->cbDFCB);
 142     for (ii = 0; ii < pDevice->cbDFCB; ii++) {
 143         if (pDevice->sRxDFCB[ii].bInUse == false) {
 144             pDevice->cbFreeDFCB--;
 145             pDevice->sRxDFCB[ii].uLifetime = pDevice->dwMaxReceiveLifetime;
 146             pDevice->sRxDFCB[ii].bInUse = true;
 147             pDevice->sRxDFCB[ii].wSequence = (pMACHeader->seq_ctrl >> 4);
 148             pDevice->sRxDFCB[ii].wFragNum = (pMACHeader->seq_ctrl & 0x000F);
 149             memcpy(&(pDevice->sRxDFCB[ii].abyAddr2[0]),
 150                    &(pMACHeader->addr2[0]),
 151                    ETH_ALEN);
 152             return(ii);
 153         }
 154     }
 155     return(pDevice->cbDFCB);
 156 }
 157
 158 /*
 159  * Description:
 160  *      Handle received fragment packet
 161  *
 162  * Parameters:
 163  *  In:
 164  *      pDevice         - Pointer to adapter
 165  *      pMACHeader      - 802.11 MAC Header of received packet
 166  *      cbFrameLength   - Frame length
 167  *      bWEP            - is WEP packet
 168  *  Out:
 169  *      none
 170  *
 171  * Return Value: true if it is valid fragment packet and we have resource to defragment; otherwise false
 172  *
 173  */
 174 bool WCTLbHandleFragment(struct vnt_private *pDevice, struct ieee80211_hdr *pMACHeader, unsigned int cbFrameLength, bool bWEP, bool bExtIV)
 175 {
 176         unsigned int uHeaderSize;
 177
 178     if (bWEP == true) {
 179         uHeaderSize = 28;
 180         if (bExtIV)
 181         // ExtIV
 182             uHeaderSize +=4;
 183     }
 184     else {
 185         uHeaderSize = 24;
 186     }
 187
 188     if (IS_FIRST_FRAGMENT_PKT(pMACHeader)) {
 189         pDevice->uCurrentDFCBIdx = WCTLuSearchDFCB(pDevice, pMACHeader);
 190         if (pDevice->uCurrentDFCBIdx < pDevice->cbDFCB) {
 191             // duplicate, we must flush previous DCB
 192             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].uLifetime = pDevice->dwMaxReceiveLifetime;
 193             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wSequence = (pMACHeader->seq_ctrl >> 4);
 194             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum = (pMACHeader->seq_ctrl & 0x000F);
 195         }
 196         else {
 197             pDevice->uCurrentDFCBIdx = WCTLuInsertDFCB(pDevice, pMACHeader);
 198             if (pDevice->uCurrentDFCBIdx == pDevice->cbDFCB) {
 199                 return(false);
 200             }
 201         }
 202         // reserve 8 byte to match MAC RX Buffer
 203         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer = (u8 *) (pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].skb->data + 8);
 204 //        pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer = (u8 *) (pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].skb->data + 4);
 205         memcpy(pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer, pMACHeader, cbFrameLength);
 206         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength = cbFrameLength;
 207         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer += cbFrameLength;
 208         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum++;
 209         //DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO "First pDevice->uCurrentDFCBIdx= %d\n", pDevice->uCurrentDFCBIdx);
 210         return(false);
 211     }
 212     else {
 213         pDevice->uCurrentDFCBIdx = WCTLuSearchDFCB(pDevice, pMACHeader);
 214         if (pDevice->uCurrentDFCBIdx != pDevice->cbDFCB) {
 215             if ((pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wSequence == (pMACHeader->seq_ctrl >> 4)) &&
 216                 (pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum == (pMACHeader->seq_ctrl & 0x000F)) &&
 217                 ((pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength + cbFrameLength - uHeaderSize) < 2346)) {
 218
 219                 memcpy(pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer, ((u8 *) (pMACHeader) + uHeaderSize), (cbFrameLength - uHeaderSize));
 220                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength += (cbFrameLength - uHeaderSize);
 221                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer += (cbFrameLength - uHeaderSize);
 222                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum++;
 223                 //DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO "Second pDevice->uCurrentDFCBIdx= %d\n", pDevice->uCurrentDFCBIdx);
 224             }
 225             else {
 226                 // seq error or frag # error flush DFCB
 227                 pDevice->cbFreeDFCB++;
 228                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].bInUse = false;
 229                 return(false);
 230             }
 231         }
 232         else {
 233             return(false);
 234         }
 235         if (IS_LAST_FRAGMENT_PKT(pMACHeader)) {
 236             //enq defragcontrolblock
 237             pDevice->cbFreeDFCB++;
 238             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].bInUse = false;
 239             //DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO "Last pDevice->uCurrentDFCBIdx= %d\n", pDevice->uCurrentDFCBIdx);
 240             return(true);
 241         }
 242         return(false);
 243     }
 244 }
 245