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/*
* 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 int ping_send(void)
{
static uchar mac[6];
struct ip_udp_hdr *ip;
ushort *s;
uchar *pkt;
/* XXX always send arp request */
memcpy(mac, NetEtherNullAddr, 6);
debug("sending ARP for %pI4\n", &NetPingIP);
NetArpWaitPacketIP = NetPingIP;
NetArpWaitPacketMAC = mac;
pkt = NetArpWaitTxPacket;
pkt += NetSetEther(pkt, mac, PROT_IP);
ip = (struct ip_udp_hdr *)pkt;
/*
* Construct an IP and ICMP header.
* (need to set no fragment bit - XXX)
*/
/* IP_HDR_SIZE / 4 (not including UDP) */
ip->ip_hl_v = 0x45;
ip->ip_tos = 0;
ip->ip_len = htons(IP_HDR_SIZE + 8);
ip->ip_id = htons(NetIPID++);
ip->ip_off = htons(IP_FLAGS_DFRAG); /* Don't fragment */
ip->ip_ttl = 255;
ip->ip_p = 0x01; /* ICMP */
ip->ip_sum = 0;
/* already in network byte order */
NetCopyIP((void *)&ip->ip_src, &NetOurIP);
/* - "" - */
NetCopyIP((void *)&ip->ip_dst, &NetPingIP);
ip->ip_sum = ~NetCksum((uchar *)ip, IP_HDR_SIZE / 2);
s = &ip->udp_src; /* XXX ICMP starts here */
s[0] = htons(0x0800); /* echo-request, code */
s[1] = 0; /* checksum */
s[2] = 0; /* identifier */
s[3] = htons(PingSeqNo++); /* sequence number */
s[1] = ~NetCksum((uchar *)s, 8/2);
/* size of the waiting packet */
NetArpWaitTxPacketSize =
(pkt - NetArpWaitTxPacket) + IP_HDR_SIZE + 8;
/* and do the ARP request */
NetArpWaitTry = 1;
NetArpWaitTimerStart = get_timer(0);
ArpRequest();
return 1; /* waiting */
}
static void ping_timeout(void)
{
eth_halt();
NetState = NETLOOP_FAIL; /* we did not get the reply */
}
static void ping_handler(uchar *pkt, unsigned dest, IPaddr_t sip,
unsigned src, unsigned len)
{
if (sip != NetPingIP)
return;
NetState = NETLOOP_SUCCESS;
}
void ping_start(void)
{
printf("Using %s device\n", eth_get_name());
NetSetTimeout(10000UL, ping_timeout);
NetSetHandler(ping_handler);
ping_send();
}
void ping_receive(struct ethernet_hdr *et, struct ip_udp_hdr *ip, int len)
{
ICMP_t *icmph = (ICMP_t *)&(ip->udp_src);
IPaddr_t src_ip;
switch (icmph->type) {
case ICMP_ECHO_REPLY:
/*
* IP header OK. Pass the packet to the
* current handler.
*/
/* XXX point to ip packet */
src_ip = NetReadIP((void *)&ip->ip_src);
NetGetHandler()((uchar *)ip, 0, src_ip, 0, 0);
return;
case ICMP_ECHO_REQUEST:
debug("Got ICMP ECHO REQUEST, return "
"%d bytes\n", ETHER_HDR_SIZE + len);
memcpy(&et->et_dest[0], &et->et_src[0], 6);
memcpy(&et->et_src[0], NetOurEther, 6);
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);
(void) eth_send((uchar *)et,
ETHER_HDR_SIZE + len);
return;
/* default:
return;*/
}
}
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