Re: Problem writing a packet to the network.

[Amith <amith@multitech.co.in>]

Vijaymahantesh Kalakoti wrote:

> Hi amith,
>
> I think the problem can be from two causes,
>
> 1. the mode in which program is running.
> 	since u r receiving the packets this may not be the  problem.
>
> 2. bind the socket. *******************************
> 	this may be the cause of it. Since u have created socket at 
> datalink layer( PF_PACKET ), & it is not bind to a device, then u may get 
> error.
> 	pls bind the socket using the sockaddr_ll structure .
> the manual page( man packet ) contains the information for this.
>
> 	
> I am not sure of my answer. But give a try.
>
> I hope it will solve u r problem.
>
> Thanks & Regards.
> vijay kalkoti
hi Vijay,
               i'am not able to bind the Socket with these values could 
u just check whether they r proper ? the man pages say it is enough to 
initialize the struct's 2 feilds - ifindex and family (as far as i cud 
understand i.e ) . Could anyone help me initialize the struct ?
when i do this bind does not succeed with " bind failed :Invalid 
argument " could someone help ?

struct sockaddr_ll addr;
addr.sll_ifindex = 0; // guessing
addr.sll_protocol = htons(ETH_P_802_3); /*defined  in if_ether.h */


    bind_return = bind(packet_socket,(struct sockaddr 
*)&addr,sizeof(addr));
      if(bind_return != 0)
      {
          perror("Bind failed :");
          exit(1);
      }
     
      printf(" Bind Success : returned %d\n",bind_return);

      while( 1 )
      {
         int count=0;
         printf("========================================= \n");
         len = read(packet_socket,buffer,sizeof(buffer));
         pkt = (struct Packet *)buffer;
            
                                                   
       if((pkt->ether.type[0] == 0X08) && (pkt->ether.type[1] ==0x06))
        {
        printf("ARP :");
        Print_Arp_Packet(pkt);
        Send_Arp_Packet(pkt);
        }
       
       
   



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