drivers/staging/bcm/Arp.c

   1
   2 /*
   3  * File Name: Arp.c
   4  * Abstract: This file contains the routines for handling ARP PACKETS
   5  */
   6 #include "headers.h"
   7 #define ARP_PKT_SIZE    60
   8
   9 /* =========================================================================
  10  * Function    - reply_to_arp_request()
  11  *
  12  * Description - When this host tries to broadcast ARP request packet through
  13  *                               the virtual interface (veth0), reply directly to upper layer.
  14  *                               This function allocates a new skb for ARP reply packet,
  15  *                               fills in the fields of the packet and then sends it to
  16  *                               upper layer.
  17  *
  18  * Parameters  - skb:   Pointer to sk_buff structure of the ARP request pkt.
  19  *
  20  * Returns     - None
  21  * =========================================================================*/
  22
  23 VOID
  24 reply_to_arp_request(struct sk_buff *skb)
  25 {
  26         PMINI_ADAPTER           Adapter;
  27         struct ArpHeader        *pArpHdr = NULL;
  28         struct ethhdr           *pethhdr = NULL;
  29         UCHAR                           uiIPHdr[4];
  30         /* Check for valid skb */
  31         if(skb == NULL)
  32         {
  33                 BCM_DEBUG_PRINT(Adapter,DBG_TYPE_PRINTK, 0, 0, "Invalid skb: Cannot reply to ARP request\n");
  34                 return;
  35         }
  36
  37
  38         Adapter = GET_BCM_ADAPTER(skb->dev);
  39         /* Print the ARP Request Packet */
  40         BCM_DEBUG_PRINT(Adapter,DBG_TYPE_TX, ARP_RESP, DBG_LVL_ALL, "ARP Packet Dump :");
  41         BCM_DEBUG_PRINT_BUFFER(Adapter,DBG_TYPE_TX, ARP_RESP, DBG_LVL_ALL, (PUCHAR)(skb->data), skb->len);
  42
  43         /*
  44          * Extract the Ethernet Header and Arp Payload including Header
  45      */
  46         pethhdr = (struct ethhdr *)skb->data;
  47         pArpHdr  = (struct ArpHeader *)(skb->data+ETH_HLEN);
  48
  49         if(Adapter->bETHCSEnabled)
  50         {
  51                 if(memcmp(pethhdr->h_source, Adapter->dev->dev_addr, ETH_ALEN))
  52                 {
  53                         bcm_kfree_skb(skb);
  54                         return;
  55                 }
  56         }
  57
  58         // Set the Ethernet Header First.
  59         memcpy(pethhdr->h_dest, pethhdr->h_source, ETH_ALEN);
  60         if(!memcmp(pethhdr->h_source, Adapter->dev->dev_addr, ETH_ALEN))
  61         {
  62                 pethhdr->h_source[5]++;
  63         }
  64
  65         /* Set the reply to ARP Reply */
  66         pArpHdr->arp.ar_op = ntohs(ARPOP_REPLY);
  67
  68         /* Set the HW Address properly */
  69         memcpy(pArpHdr->ar_sha, pethhdr->h_source, ETH_ALEN);
  70         memcpy(pArpHdr->ar_tha, pethhdr->h_dest, ETH_ALEN);
  71
  72         // Swapping the IP Adddress
  73         memcpy(uiIPHdr,pArpHdr->ar_sip,4);
  74         memcpy(pArpHdr->ar_sip,pArpHdr->ar_tip,4);
  75         memcpy(pArpHdr->ar_tip,uiIPHdr,4);
  76
  77         /* Print the ARP Reply Packet */
  78
  79         BCM_DEBUG_PRINT(Adapter,DBG_TYPE_TX, ARP_RESP, DBG_LVL_ALL, "ARP REPLY PACKET: ");
  80
  81         /* Send the Packet to upper layer */
  82         BCM_DEBUG_PRINT_BUFFER(Adapter,DBG_TYPE_TX, ARP_RESP, DBG_LVL_ALL, (PUCHAR)(skb->data), skb->len);
  83
  84         skb->protocol = eth_type_trans(skb,skb->dev);
  85         skb->pkt_type = PACKET_HOST;
  86
  87 //      skb->mac.raw=skb->data+LEADER_SIZE;
  88         skb_set_mac_header (skb, LEADER_SIZE);
  89         netif_rx(skb);
  90         BCM_DEBUG_PRINT(Adapter,DBG_TYPE_TX, ARP_RESP, DBG_LVL_ALL, "<=============\n");
  91         return;
  92 }
  93
  94