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 41/*--------------------- Static Definitions -------------------------*/ 42 43/*--------------------- Static Classes ----------------------------*/ 44 45/*--------------------- Static Variables --------------------------*/ 46 47/*--------------------- Static Functions --------------------------*/ 48 49/*--------------------- Export Variables --------------------------*/ 50 51/* 52 * Description: 53 * Scan Rx cache. Return true if packet is duplicate, else 54 * inserts in receive cache and returns false. 55 * 56 * Parameters: 57 * In: 58 * pCache - Receive packets history 59 * pMACHeader - 802.11 MAC Header of received packet 60 * Out: 61 * none 62 * 63 * Return Value: true if packet duplicate; otherwise false 64 * 65 */ 66 67bool WCTLbIsDuplicate(PSCache pCache, PS802_11Header pMACHeader) 68{ 69 unsigned int uIndex; 70 unsigned int ii; 71 PSCacheEntry pCacheEntry; 72 73 if (IS_FC_RETRY(pMACHeader)) { 74 uIndex = pCache->uInPtr; 75 for (ii = 0; ii < DUPLICATE_RX_CACHE_LENGTH; ii++) { 76 pCacheEntry = &(pCache->asCacheEntry[uIndex]); 77 if ((pCacheEntry->wFmSequence == pMACHeader->wSeqCtl) && 78 ether_addr_equal(pCacheEntry->abyAddr2, 79 pMACHeader->abyAddr2)) { 80 /* Duplicate match */ 81 return true; 82 } 83 ADD_ONE_WITH_WRAP_AROUND(uIndex, DUPLICATE_RX_CACHE_LENGTH); 84 } 85 } 86 /* Not fount in cache - insert */ 87 pCacheEntry = &pCache->asCacheEntry[pCache->uInPtr]; 88 pCacheEntry->wFmSequence = pMACHeader->wSeqCtl; 89 memcpy(&(pCacheEntry->abyAddr2[0]), &(pMACHeader->abyAddr2[0]), ETH_ALEN); 90 ADD_ONE_WITH_WRAP_AROUND(pCache->uInPtr, DUPLICATE_RX_CACHE_LENGTH); 91 return false; 92} 93 94/* 95 * Description: 96 * Found if sequence number of received fragment packet in Defragment Database 97 * 98 * Parameters: 99 * In: 100 * pDevice - Pointer to adapter 101 * pMACHeader - 802.11 MAC Header of received packet 102 * Out: 103 * none 104 * 105 * Return Value: index number in Defragment Database 106 * 107 */ 108unsigned int WCTLuSearchDFCB(struct vnt_private *pDevice, 109 PS802_11Header pMACHeader) 110{ 111 unsigned int ii; 112 113 for (ii = 0; ii < pDevice->cbDFCB; ii++) { 114 if (pDevice->sRxDFCB[ii].bInUse && 115 ether_addr_equal(pDevice->sRxDFCB[ii].abyAddr2, 116 pMACHeader->abyAddr2)) { 117 return ii; 118 } 119 } 120 return pDevice->cbDFCB; 121} 122 123/* 124 * Description: 125 * Insert received fragment packet in Defragment Database 126 * 127 * Parameters: 128 * In: 129 * pDevice - Pointer to adapter 130 * pMACHeader - 802.11 MAC Header of received packet 131 * Out: 132 * none 133 * 134 * Return Value: index number in Defragment Database 135 * 136 */ 137unsigned int WCTLuInsertDFCB(struct vnt_private *pDevice, PS802_11Header pMACHeader) 138{ 139 unsigned int ii; 140 141 if (pDevice->cbFreeDFCB == 0) 142 return pDevice->cbDFCB; 143 for (ii = 0; ii < pDevice->cbDFCB; ii++) { 144 if (!pDevice->sRxDFCB[ii].bInUse) { 145 pDevice->cbFreeDFCB--; 146 pDevice->sRxDFCB[ii].uLifetime = pDevice->dwMaxReceiveLifetime; 147 pDevice->sRxDFCB[ii].bInUse = true; 148 pDevice->sRxDFCB[ii].wSequence = (pMACHeader->wSeqCtl >> 4); 149 pDevice->sRxDFCB[ii].wFragNum = (pMACHeader->wSeqCtl & 0x000F); 150 memcpy(&(pDevice->sRxDFCB[ii].abyAddr2[0]), &(pMACHeader->abyAddr2[0]), ETH_ALEN); 151 return ii; 152 } 153 } 154 return pDevice->cbDFCB; 155} 156 157/* 158 * Description: 159 * Handle received fragment packet 160 * 161 * Parameters: 162 * In: 163 * pDevice - Pointer to adapter 164 * pMACHeader - 802.11 MAC Header of received packet 165 * cbFrameLength - Frame length 166 * bWEP - is WEP packet 167 * Out: 168 * none 169 * 170 * Return Value: true if it is valid fragment packet and we have resource to defragment; otherwise false 171 * 172 */ 173bool WCTLbHandleFragment(struct vnt_private *pDevice, PS802_11Header pMACHeader, 174 unsigned int cbFrameLength, bool bWEP, bool bExtIV) 175{ 176 unsigned int uHeaderSize; 177 178 if (bWEP) { 179 uHeaderSize = 28; 180 if (bExtIV) 181 // ExtIV 182 uHeaderSize += 4; 183 } else { 184 uHeaderSize = 24; 185 } 186 187 if (IS_FIRST_FRAGMENT_PKT(pMACHeader)) { 188 pDevice->uCurrentDFCBIdx = WCTLuSearchDFCB(pDevice, pMACHeader); 189 if (pDevice->uCurrentDFCBIdx < pDevice->cbDFCB) { 190 // duplicate, we must flush previous DCB 191 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].uLifetime = pDevice->dwMaxReceiveLifetime; 192 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wSequence = (pMACHeader->wSeqCtl >> 4); 193 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum = (pMACHeader->wSeqCtl & 0x000F); 194 } else { 195 pDevice->uCurrentDFCBIdx = WCTLuInsertDFCB(pDevice, pMACHeader); 196 if (pDevice->uCurrentDFCBIdx == pDevice->cbDFCB) 197 return false; 198 } 199 // reserve 4 byte to match MAC RX Buffer 200 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer = (unsigned char *)(pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].skb->data + 4); 201 memcpy(pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer, pMACHeader, cbFrameLength); 202 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength = cbFrameLength; 203 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer += cbFrameLength; 204 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum++; 205 return false; 206 } else { 207 pDevice->uCurrentDFCBIdx = WCTLuSearchDFCB(pDevice, pMACHeader); 208 if (pDevice->uCurrentDFCBIdx != pDevice->cbDFCB) { 209 if ((pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wSequence == (pMACHeader->wSeqCtl >> 4)) && 210 (pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum == (pMACHeader->wSeqCtl & 0x000F)) && 211 ((pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength + cbFrameLength - uHeaderSize) < 2346)) { 212 memcpy(pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer, ((unsigned char *)(pMACHeader) + uHeaderSize), (cbFrameLength - uHeaderSize)); 213 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].cbFrameLength += (cbFrameLength - uHeaderSize); 214 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].pbyRxBuffer += (cbFrameLength - uHeaderSize); 215 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].wFragNum++; 216 } else { 217 // seq error or frag # error flush DFCB 218 pDevice->cbFreeDFCB++; 219 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].bInUse = false; 220 return false; 221 } 222 } else { 223 return false; 224 } 225 if (IS_LAST_FRAGMENT_PKT(pMACHeader)) { 226 //enq defragcontrolblock 227 pDevice->cbFreeDFCB++; 228 pDevice->sRxDFCB[pDevice->uCurrentDFCBIdx].bInUse = false; 229 return true; 230 } 231 return false; 232 } 233} 234