release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/usb/Beceem_driver/src/Common/Arp.c

   1 /*
   2 * Arp.c
   3 *
   4 *Copyright (C) 2010 Beceem Communications, Inc.
   5 *
   6 *This program is free software: you can redistribute it and/or modify
   7 *it under the terms of the GNU General Public License version 2 as
   8 *published by the Free Software Foundation.
   9 *
  10 *This program is distributed in the hope that it will be useful,but
  11 *WITHOUT ANY WARRANTY; without even the implied warranty of
  12 *MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  13 *See the GNU General Public License for more details.
  14 *
  15 *You should have received a copy of the GNU General Public License
  16 *along 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 */
  20
  21 /**********************************************************************
  22 *       This file contains the routines for handling ARP PACKETS
  23 ***********************************************************************/
  24
  25
  26 #include <headers.h>
  27 #define ARP_PKT_SIZE    60
  28
  29 /* =========================================================================
  30  * Function    - reply_to_arp_request()
  31  *
  32  * Description - When this host tries to broadcast ARP request packet through
  33  *                               the virtual interface (veth0), reply directly to upper layer.
  34  *                               This function allocates a new skb for ARP reply packet,
  35  *                               fills in the fields of the packet and then sends it to
  36  *                               upper layer.
  37  *
  38  * Parameters  - skb:   Pointer to sk_buff structure of the ARP request pkt.
  39  *
  40  * Returns     - None
  41  * =========================================================================*/
  42
  43 VOID
  44 reply_to_arp_request(struct sk_buff *skb)
  45 {
  46         PMINI_ADAPTER           Adapter;
  47         struct ArpHeader        *pArpHdr = NULL;
  48         struct ethhdr           *pethhdr = NULL;
  49         UCHAR                           uiIPHdr[4];
  50         /* Check for valid skb */
  51         if(skb == NULL)
  52         {
  53                 BCM_DEBUG_PRINT(Adapter,DBG_TYPE_PRINTK, 0, 0, "Invalid skb: Cannot reply to ARP request\n");
  54                 return;
  55         }
  56
  57
  58         Adapter = GET_BCM_ADAPTER(skb->dev);
  59         /* Print the ARP Request Packet */
  60         BCM_DEBUG_PRINT(Adapter,DBG_TYPE_TX, ARP_RESP, DBG_LVL_ALL, "ARP Packet Dump :");
  61         BCM_DEBUG_PRINT_BUFFER(Adapter,DBG_TYPE_TX, ARP_RESP, DBG_LVL_ALL, (PUCHAR)(skb->data), skb->len);
  62
  63         /*
  64          * Extract the Ethernet Header and Arp Payload including Header
  65      */
  66         pethhdr = (struct ethhdr *)skb->data;
  67         pArpHdr  = (struct ArpHeader *)(skb->data+ETH_HLEN);
  68
  69         if(Adapter->bETHCSEnabled)
  70         {
  71                 if(memcmp(pethhdr->h_source, Adapter->dev->dev_addr, ETH_ALEN))
  72                 {
  73                         bcm_kfree_skb(skb);
  74                         return;
  75                 }
  76         }
  77
  78         // Set the Ethernet Header First.
  79         memcpy(pethhdr->h_dest, pethhdr->h_source, ETH_ALEN);
  80         if(!memcmp(pethhdr->h_source, Adapter->dev->dev_addr, ETH_ALEN))
  81         {
  82                 pethhdr->h_source[5]++;
  83         }
  84
  85         /* Set the reply to ARP Reply */
  86         pArpHdr->arp.ar_op = ntohs(ARPOP_REPLY);
  87
  88         /* Set the HW Address properly */
  89         memcpy(pArpHdr->ar_sha, pethhdr->h_source, ETH_ALEN);
  90         memcpy(pArpHdr->ar_tha, pethhdr->h_dest, ETH_ALEN);
  91
  92         // Swapping the IP Adddress
  93         memcpy(uiIPHdr,pArpHdr->ar_sip,4);
  94         memcpy(pArpHdr->ar_sip,pArpHdr->ar_tip,4);
  95         memcpy(pArpHdr->ar_tip,uiIPHdr,4);
  96
  97         /* Print the ARP Reply Packet */
  98
  99         BCM_DEBUG_PRINT(Adapter,DBG_TYPE_TX, ARP_RESP, DBG_LVL_ALL, "ARP REPLY PACKET: ");
 100
 101         /* Send the Packet to upper layer */
 102         BCM_DEBUG_PRINT_BUFFER(Adapter,DBG_TYPE_TX, ARP_RESP, DBG_LVL_ALL, (PUCHAR)(skb->data), skb->len);
 103
 104         skb->protocol = eth_type_trans(skb,skb->dev);
 105         skb->pkt_type = PACKET_HOST;
 106
 107 //      skb->mac.raw=skb->data+LEADER_SIZE;
 108         skb_set_mac_header (skb, LEADER_SIZE);
 109         netif_rx(skb);
 110         BCM_DEBUG_PRINT(Adapter,DBG_TYPE_TX, ARP_RESP, DBG_LVL_ALL, "<=============\n");
 111         return;
 112 }
 113
 114