1 /* 2 * Copied from Linux Monitor (LiMon) - Networking. 3 * 4 * Copyright 1994 - 2000 Neil Russell. 5 * (See License) 6 * Copyright 2000 Roland Borde 7 * Copyright 2000 Paolo Scaffardi 8 * Copyright 2000-2002 Wolfgang Denk, wd@denx.de 9 */ 10 11 #include "ping.h" 12 #include "arp.h" 13 14 static ushort PingSeqNo; 15 16 /* The ip address to ping */ 17 IPaddr_t NetPingIP; 18 19 static void set_icmp_header(uchar *pkt, IPaddr_t dest) 20 { 21 /* 22 * Construct an IP and ICMP header. 23 */ 24 struct ip_hdr *ip = (struct ip_hdr *)pkt; 25 struct icmp_hdr *icmp = (struct icmp_hdr *)(pkt + IP_HDR_SIZE); 26 27 net_set_ip_header(pkt, dest, NetOurIP); 28 29 ip->ip_len = htons(IP_ICMP_HDR_SIZE); 30 ip->ip_p = IPPROTO_ICMP; 31 ip->ip_sum = ~NetCksum((uchar *)ip, IP_HDR_SIZE >> 1); 32 33 icmp->type = ICMP_ECHO_REQUEST; 34 icmp->code = 0; 35 icmp->checksum = 0; 36 icmp->un.echo.id = 0; 37 icmp->un.echo.sequence = htons(PingSeqNo++); 38 icmp->checksum = ~NetCksum((uchar *)icmp, ICMP_HDR_SIZE >> 1); 39 } 40 41 static int ping_send(void) 42 { 43 uchar *pkt; 44 int eth_hdr_size; 45 46 /* XXX always send arp request */ 47 48 debug("sending ARP for %pI4\n", &NetPingIP); 49 50 NetArpWaitPacketIP = NetPingIP; 51 52 eth_hdr_size = NetSetEther(NetArpWaitTxPacket, NetEtherNullAddr, 53 PROT_IP); 54 pkt = NetArpWaitTxPacket + eth_hdr_size; 55 56 set_icmp_header(pkt, NetPingIP); 57 58 /* size of the waiting packet */ 59 NetArpWaitTxPacketSize = eth_hdr_size + IP_ICMP_HDR_SIZE; 60 61 /* and do the ARP request */ 62 NetArpWaitTry = 1; 63 NetArpWaitTimerStart = get_timer(0); 64 ArpRequest(); 65 return 1; /* waiting */ 66 } 67 68 static void ping_timeout(void) 69 { 70 eth_halt(); 71 net_set_state(NETLOOP_FAIL); /* we did not get the reply */ 72 } 73 74 void ping_start(void) 75 { 76 printf("Using %s device\n", eth_get_name()); 77 NetSetTimeout(10000UL, ping_timeout); 78 79 ping_send(); 80 } 81 82 void ping_receive(struct ethernet_hdr *et, struct ip_udp_hdr *ip, int len) 83 { 84 struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src; 85 IPaddr_t src_ip; 86 int eth_hdr_size; 87 88 switch (icmph->type) { 89 case ICMP_ECHO_REPLY: 90 src_ip = NetReadIP((void *)&ip->ip_src); 91 if (src_ip == NetPingIP) 92 net_set_state(NETLOOP_SUCCESS); 93 return; 94 case ICMP_ECHO_REQUEST: 95 eth_hdr_size = net_update_ether(et, et->et_src, PROT_IP); 96 97 debug("Got ICMP ECHO REQUEST, return " 98 "%d bytes\n", eth_hdr_size + len); 99 100 ip->ip_sum = 0; 101 ip->ip_off = 0; 102 NetCopyIP((void *)&ip->ip_dst, &ip->ip_src); 103 NetCopyIP((void *)&ip->ip_src, &NetOurIP); 104 ip->ip_sum = ~NetCksum((uchar *)ip, 105 IP_HDR_SIZE >> 1); 106 107 icmph->type = ICMP_ECHO_REPLY; 108 icmph->checksum = 0; 109 icmph->checksum = ~NetCksum((uchar *)icmph, 110 (len - IP_HDR_SIZE) >> 1); 111 NetSendPacket((uchar *)et, eth_hdr_size + len); 112 return; 113 /* default: 114 return;*/ 115 } 116 } 117