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
  43
  44 // static int          msglevel                =MSG_LEVEL_INFO;
  45
  46
  47
  48
  49 /*
  50  * Description:
  51  *      Scan Rx cache.  Return true if packet is duplicate, else
  52  *      inserts in receive cache and returns false.
  53  *
  54  * Parameters:
  55  *  In:
  56  *      pCache      - Receive packets history
  57  *      pMACHeader  - 802.11 MAC Header of received packet
  58  *  Out:
  59  *      none
  60  *
  61  * Return Value: true if packet duplicate; otherwise false
  62  *
  63  */
  64
  65 bool WCTLbIsDuplicate (PSCache pCache, struct ieee80211_hdr *pMACHeader)
  66 {
  67     unsigned int            uIndex;
  68     unsigned int            ii;
  69     PSCacheEntry    pCacheEntry;
  70
  71     if (IS_FC_RETRY(pMACHeader)) {
  72
  73         uIndex = pCache->uInPtr;
  74         for (ii = 0; ii < DUPLICATE_RX_CACHE_LENGTH; ii++) {
  75             pCacheEntry = &(pCache->asCacheEntry[uIndex]);
  76             if ((pCacheEntry->wFmSequence == pMACHeader->seq_ctrl) &&
  77                 (!compare_ether_addr(&(pCacheEntry->abyAddr2[0]),
  78                                      &(pMACHeader->addr2[0]))) &&
  79                 (LOBYTE(pCacheEntry->wFrameCtl) == LOBYTE(pMACHeader->frame_control))
  80                 ) {
  81                 /* Duplicate match */
  82                 return true;
  83             }
  84             ADD_ONE_WITH_WRAP_AROUND(uIndex, DUPLICATE_RX_CACHE_LENGTH);
  85         }
  86     }
  87     /* Not found in cache - insert */
  88     pCacheEntry = &pCache->asCacheEntry[pCache->uInPtr];
  89     pCacheEntry->wFmSequence = pMACHeader->seq_ctrl;
  90     memcpy(&(pCacheEntry->abyAddr2[0]), &(pMACHeader->addr2[0]), ETH_ALEN);
  91     pCacheEntry->wFrameCtl = pMACHeader->frame_control;
  92     ADD_ONE_WITH_WRAP_AROUND(pCache->uInPtr, DUPLICATE_RX_CACHE_LENGTH);
  93     return false;
  94 }
  95
  96 /*
  97  * Description:
  98  *      Found if sequence number of received fragment packet in Defragment Database
  99  *
 100  * Parameters:
 101  *  In:
 102  *      pDevice     - Pointer to adapter
 103  *      pMACHeader  - 802.11 MAC Header of received packet
 104  *  Out:
 105  *      none
 106  *
 107  * Return Value: index number in Defragment Database
 108  *
 109  */
 110
 111 unsigned int WCTLuSearchDFCB(struct vnt_private *pDevice,
 112                              struct ieee80211_hdr *pMACHeader)
 113 {
 114         unsigned int ii;
 115
 116         for (ii = 0; ii < pDevice->cbDFCB; ii++) {
 117                 if ((pDevice->sRxDFCB[ii].bInUse == true) &&
 118                     (!compare_ether_addr(&(pDevice->sRxDFCB[ii].abyAddr2[0]),
 119                                           &(pMACHeader->addr2[0])))) {
 120                         return ii;
 121                 }
 122         }
 123         return pDevice->cbDFCB;
 124 }
 125
 126 /*
 127  * Description:
 128  *      Insert received fragment packet in Defragment Database
 129  *
 130  * Parameters:
 131  *  In:
 132  *      pDevice     - Pointer to adapter
 133  *      pMACHeader  - 802.11 MAC Header of received packet
 134  *  Out:
 135  *      none
 136  *
 137  * Return Value: index number in Defragment Database
 138  *
 139  */
 140 unsigned int WCTLuInsertDFCB(struct vnt_private *pDevice,
 141                              struct ieee80211_hdr *pMACHeader)
 142 {
 143         unsigned int ii;
 144
 145     if (pDevice->cbFreeDFCB == 0)
 146         return(pDevice->cbDFCB);
 147     for (ii = 0; ii < pDevice->cbDFCB; ii++) {
 148         if (pDevice->sRxDFCB[ii].bInUse == false) {
 149             pDevice->cbFreeDFCB--;
 150             pDevice->sRxDFCB[ii].uLifetime = pDevice->dwMaxReceiveLifetime;
 151             pDevice->sRxDFCB[ii].bInUse = true;
 152             pDevice->sRxDFCB[ii].wSequence = (pMACHeader->seq_ctrl >> 4);
 153             pDevice->sRxDFCB[ii].wFragNum = (pMACHeader->seq_ctrl & 0x000F);
 154             memcpy(&(pDevice->sRxDFCB[ii].abyAddr2[0]),
 155                    &(pMACHeader->addr2[0]),
 156                    ETH_ALEN);
 157             return(ii);
 158         }
 159     }
 160     return(pDevice->cbDFCB);
 161 }
 162
 163
 164 /*
 165  * Description:
 166  *      Handle received fragment packet
 167  *
 168  * Parameters:
 169  *  In:
 170  *      pDevice         - Pointer to adapter
 171  *      pMACHeader      - 802.11 MAC Header of received packet
 172  *      cbFrameLength   - Frame length
 173  *      bWEP            - is WEP packet
 174  *  Out:
 175  *      none
 176  *
 177  * Return Value: true if it is valid fragment packet and we have resource to defragment; otherwise false
 178  *
 179  */
 180 bool WCTLbHandleFragment(struct vnt_private *pDevice, struct ieee80211_hdr *pMACHeader, unsigned int cbFrameLength, bool bWEP, bool bExtIV)
 181 {
 182         unsigned int uHeaderSize;
 183
 184
 185     if (bWEP == true) {
 186         uHeaderSize = 28;
 187         if (bExtIV)
 188         // ExtIV
 189             uHeaderSize +=4;
 190     }
 191     else {
 192         uHeaderSize = 24;
 193     }
 194
 195     if (IS_FIRST_FRAGMENT_PKT(pMACHeader)) {
 196         pDevice->uCurrentDFCBIdx = WCTLuSearchDFCB(pDevice, pMACHeader);
 197         if (pDevice->uCurrentDFCBIdx < pDevice->cbDFCB) {
 198             // duplicate, we must flush previous DCB
 199             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].uLifetime = pDevice->dwMaxReceiveLifetime;
 200             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wSequence = (pMACHeader->seq_ctrl >> 4);
 201             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum = (pMACHeader->seq_ctrl & 0x000F);
 202         }
 203         else {
 204             pDevice->uCurrentDFCBIdx = WCTLuInsertDFCB(pDevice, pMACHeader);
 205             if (pDevice->uCurrentDFCBIdx == pDevice->cbDFCB) {
 206                 return(false);
 207             }
 208         }
 209         // reserve 8 byte to match MAC RX Buffer
 210         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer = (u8 *) (pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].skb->data + 8);
 211 //        pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer = (u8 *) (pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].skb->data + 4);
 212         memcpy(pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer, pMACHeader, cbFrameLength);
 213         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength = cbFrameLength;
 214         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer += cbFrameLength;
 215         pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum++;
 216         //DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO "First pDevice->uCurrentDFCBIdx= %d\n", pDevice->uCurrentDFCBIdx);
 217         return(false);
 218     }
 219     else {
 220         pDevice->uCurrentDFCBIdx = WCTLuSearchDFCB(pDevice, pMACHeader);
 221         if (pDevice->uCurrentDFCBIdx != pDevice->cbDFCB) {
 222             if ((pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wSequence == (pMACHeader->seq_ctrl >> 4)) &&
 223                 (pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum == (pMACHeader->seq_ctrl & 0x000F)) &&
 224                 ((pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength + cbFrameLength - uHeaderSize) < 2346)) {
 225
 226                 memcpy(pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer, ((u8 *) (pMACHeader) + uHeaderSize), (cbFrameLength - uHeaderSize));
 227                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength += (cbFrameLength - uHeaderSize);
 228                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer += (cbFrameLength - uHeaderSize);
 229                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum++;
 230                 //DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO "Second pDevice->uCurrentDFCBIdx= %d\n", pDevice->uCurrentDFCBIdx);
 231             }
 232             else {
 233                 // seq error or frag # error flush DFCB
 234                 pDevice->cbFreeDFCB++;
 235                 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].bInUse = false;
 236                 return(false);
 237             }
 238         }
 239         else {
 240             return(false);
 241         }
 242         if (IS_LAST_FRAGMENT_PKT(pMACHeader)) {
 243             //enq defragcontrolblock
 244             pDevice->cbFreeDFCB++;
 245             pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].bInUse = false;
 246             //DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO "Last pDevice->uCurrentDFCBIdx= %d\n", pDevice->uCurrentDFCBIdx);
 247             return(true);
 248         }
 249         return(false);
 250     }
 251 }
 252
 253