/*
   *	Copied from Linux Monitor (LiMon) - Networking.
   *
   *	Copyright 1994 - 2000 Neil Russell.
   *	(See License)
   *	Copyright 2000 Roland Borde
   *	Copyright 2000 Paolo Scaffardi
   *	Copyright 2000-2002 Wolfgang Denk, wd@denx.de
   */
  
  #include "ping.h"
  #include "arp.h"
  
  static ushort PingSeqNo;
  
  /* The ip address to ping */
  IPaddr_t NetPingIP;

  static void set_icmp_header(uchar *pkt, IPaddr_t dest)
  {
  	/*
  	 *	Construct an IP and ICMP header.
  	 */
  	struct ip_hdr *ip = (struct ip_hdr *)pkt;
  	struct icmp_hdr *icmp = (struct icmp_hdr *)(pkt + IP_HDR_SIZE);
  
  	net_set_ip_header(pkt, dest, NetOurIP);
  
  	ip->ip_len   = htons(IP_ICMP_HDR_SIZE);
  	ip->ip_p     = IPPROTO_ICMP;
  	ip->ip_sum   = ~NetCksum((uchar *)ip, IP_HDR_SIZE >> 1);
  
  	icmp->type = ICMP_ECHO_REQUEST;
  	icmp->code = 0;
  	icmp->checksum = 0;
  	icmp->un.echo.id = 0;
  	icmp->un.echo.sequence = htons(PingSeqNo++);
  	icmp->checksum = ~NetCksum((uchar *)icmp, ICMP_HDR_SIZE	>> 1);
  }

  static int ping_send(void)
  {

  	uchar *pkt;

  	int eth_hdr_size;

  
  	/* XXX always send arp request */

  	debug_cond(DEBUG_DEV_PKT, "sending ARP for %pI4
  ", &NetPingIP);

  
  	NetArpWaitPacketIP = NetPingIP;

  	eth_hdr_size = NetSetEther(NetTxPacket, NetEtherNullAddr, PROT_IP);
  	pkt = (uchar *)NetTxPacket + eth_hdr_size;

  	set_icmp_header(pkt, NetPingIP);

  
  	/* size of the waiting packet */

  	NetArpWaitTxPacketSize = eth_hdr_size + IP_ICMP_HDR_SIZE;

  
  	/* and do the ARP request */
  	NetArpWaitTry = 1;
  	NetArpWaitTimerStart = get_timer(0);
  	ArpRequest();
  	return 1;	/* waiting */
  }
  
  static void ping_timeout(void)
  {
  	eth_halt();

  	net_set_state(NETLOOP_FAIL);	/* we did not get the reply */

  }

  void ping_start(void)
  {
  	printf("Using %s device
  ", eth_get_name());
  	NetSetTimeout(10000UL, ping_timeout);

  
  	ping_send();
  }

  void ping_receive(struct ethernet_hdr *et, struct ip_udp_hdr *ip, int len)

  {

  	struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src;

  	IPaddr_t src_ip;

  	int eth_hdr_size;

  
  	switch (icmph->type) {
  	case ICMP_ECHO_REPLY:

  		src_ip = NetReadIP((void *)&ip->ip_src);

  		if (src_ip == NetPingIP)

  			net_set_state(NETLOOP_SUCCESS);

  		return;
  	case ICMP_ECHO_REQUEST:

  		eth_hdr_size = net_update_ether(et, et->et_src, PROT_IP);

  		debug_cond(DEBUG_DEV_PKT, "Got ICMP ECHO REQUEST, return "

  			"%d bytes
  ", eth_hdr_size + len);

  
  		ip->ip_sum = 0;
  		ip->ip_off = 0;
  		NetCopyIP((void *)&ip->ip_dst, &ip->ip_src);
  		NetCopyIP((void *)&ip->ip_src, &NetOurIP);
  		ip->ip_sum = ~NetCksum((uchar *)ip,

  				       IP_HDR_SIZE >> 1);

  
  		icmph->type = ICMP_ECHO_REPLY;
  		icmph->checksum = 0;
  		icmph->checksum = ~NetCksum((uchar *)icmph,

  			(len - IP_HDR_SIZE) >> 1);

  		NetSendPacket((uchar *)et, eth_hdr_size + len);

  		return;
  /*	default:
  		return;*/
  	}
  }