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 int ping_send(void) 20 { 21 static uchar mac[6]; 22 struct ip_udp_hdr *ip; 23 ushort *s; 24 uchar *pkt; 25 26 /* XXX always send arp request */ 27 28 memcpy(mac, NetEtherNullAddr, 6); 29 30 debug("sending ARP for %pI4\n", &NetPingIP); 31 32 NetArpWaitPacketIP = NetPingIP; 33 NetArpWaitPacketMAC = mac; 34 35 pkt = NetArpWaitTxPacket; 36 pkt += NetSetEther(pkt, mac, PROT_IP); 37 38 ip = (struct ip_udp_hdr *)pkt; 39 40 /* 41 * Construct an IP and ICMP header. 42 * (need to set no fragment bit - XXX) 43 */ 44 /* IP_HDR_SIZE / 4 (not including UDP) */ 45 ip->ip_hl_v = 0x45; 46 ip->ip_tos = 0; 47 ip->ip_len = htons(IP_HDR_SIZE + 8); 48 ip->ip_id = htons(NetIPID++); 49 ip->ip_off = htons(IP_FLAGS_DFRAG); /* Don't fragment */ 50 ip->ip_ttl = 255; 51 ip->ip_p = 0x01; /* ICMP */ 52 ip->ip_sum = 0; 53 /* already in network byte order */ 54 NetCopyIP((void *)&ip->ip_src, &NetOurIP); 55 /* - "" - */ 56 NetCopyIP((void *)&ip->ip_dst, &NetPingIP); 57 ip->ip_sum = ~NetCksum((uchar *)ip, IP_HDR_SIZE / 2); 58 59 s = &ip->udp_src; /* XXX ICMP starts here */ 60 s[0] = htons(0x0800); /* echo-request, code */ 61 s[1] = 0; /* checksum */ 62 s[2] = 0; /* identifier */ 63 s[3] = htons(PingSeqNo++); /* sequence number */ 64 s[1] = ~NetCksum((uchar *)s, 8/2); 65 66 /* size of the waiting packet */ 67 NetArpWaitTxPacketSize = 68 (pkt - NetArpWaitTxPacket) + IP_HDR_SIZE + 8; 69 70 /* and do the ARP request */ 71 NetArpWaitTry = 1; 72 NetArpWaitTimerStart = get_timer(0); 73 ArpRequest(); 74 return 1; /* waiting */ 75 } 76 77 static void ping_timeout(void) 78 { 79 eth_halt(); 80 NetState = NETLOOP_FAIL; /* we did not get the reply */ 81 } 82 83 static void ping_handler(uchar *pkt, unsigned dest, IPaddr_t sip, 84 unsigned src, unsigned len) 85 { 86 if (sip != NetPingIP) 87 return; 88 89 NetState = NETLOOP_SUCCESS; 90 } 91 92 void ping_start(void) 93 { 94 printf("Using %s device\n", eth_get_name()); 95 NetSetTimeout(10000UL, ping_timeout); 96 NetSetHandler(ping_handler); 97 98 ping_send(); 99 } 100 101 void ping_receive(struct ethernet_hdr *et, struct ip_udp_hdr *ip, int len) 102 { 103 ICMP_t *icmph = (ICMP_t *)&(ip->udp_src); 104 IPaddr_t src_ip; 105 106 switch (icmph->type) { 107 case ICMP_ECHO_REPLY: 108 /* 109 * IP header OK. Pass the packet to the 110 * current handler. 111 */ 112 /* XXX point to ip packet */ 113 src_ip = NetReadIP((void *)&ip->ip_src); 114 NetGetHandler()((uchar *)ip, 0, src_ip, 0, 0); 115 return; 116 case ICMP_ECHO_REQUEST: 117 debug("Got ICMP ECHO REQUEST, return " 118 "%d bytes\n", ETHER_HDR_SIZE + len); 119 120 memcpy(&et->et_dest[0], &et->et_src[0], 6); 121 memcpy(&et->et_src[0], NetOurEther, 6); 122 123 ip->ip_sum = 0; 124 ip->ip_off = 0; 125 NetCopyIP((void *)&ip->ip_dst, &ip->ip_src); 126 NetCopyIP((void *)&ip->ip_src, &NetOurIP); 127 ip->ip_sum = ~NetCksum((uchar *)ip, 128 IP_HDR_SIZE >> 1); 129 130 icmph->type = ICMP_ECHO_REPLY; 131 icmph->checksum = 0; 132 icmph->checksum = ~NetCksum((uchar *)icmph, 133 (len - IP_HDR_SIZE) >> 1); 134 (void) eth_send((uchar *)et, 135 ETHER_HDR_SIZE + len); 136 return; 137 /* default: 138 return;*/ 139 } 140 } 141