net/ping.c

   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  *      SPDX-License-Identifier:        GPL-2.0
  10  */
  11
  12 #include "ping.h"
  13 #include "arp.h"
  14
  15 static ushort ping_seq_number;
  16
  17 /* The ip address to ping */
  18 struct in_addr net_ping_ip;
  19
  20 static void set_icmp_header(uchar *pkt, struct in_addr dest)
  21 {
  22         /*
  23          *      Construct an IP and ICMP header.
  24          */
  25         struct ip_hdr *ip = (struct ip_hdr *)pkt;
  26         struct icmp_hdr *icmp = (struct icmp_hdr *)(pkt + IP_HDR_SIZE);
  27
  28         net_set_ip_header(pkt, dest, net_ip);
  29
  30         ip->ip_len   = htons(IP_ICMP_HDR_SIZE);
  31         ip->ip_p     = IPPROTO_ICMP;
  32         ip->ip_sum   = compute_ip_checksum(ip, IP_HDR_SIZE);
  33
  34         icmp->type = ICMP_ECHO_REQUEST;
  35         icmp->code = 0;
  36         icmp->checksum = 0;
  37         icmp->un.echo.id = 0;
  38         icmp->un.echo.sequence = htons(ping_seq_number++);
  39         icmp->checksum = compute_ip_checksum(icmp, ICMP_HDR_SIZE);
  40 }
  41
  42 static int ping_send(void)
  43 {
  44         uchar *pkt;
  45         int eth_hdr_size;
  46
  47         /* XXX always send arp request */
  48
  49         debug_cond(DEBUG_DEV_PKT, "sending ARP for %pI4\n", &net_ping_ip);
  50
  51         net_arp_wait_packet_ip = net_ping_ip;
  52
  53         eth_hdr_size = net_set_ether(net_tx_packet, net_null_ethaddr, PROT_IP);
  54         pkt = (uchar *)net_tx_packet + eth_hdr_size;
  55
  56         set_icmp_header(pkt, net_ping_ip);
  57
  58         /* size of the waiting packet */
  59         arp_wait_tx_packet_size = eth_hdr_size + IP_ICMP_HDR_SIZE;
  60
  61         /* and do the ARP request */
  62         arp_wait_try = 1;
  63         arp_wait_timer_start = get_timer(0);
  64         arp_request();
  65         return 1;       /* waiting */
  66 }
  67
  68 static void ping_timeout_handler(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         net_set_timeout_handler(10000UL, ping_timeout_handler);
  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         struct in_addr src_ip;
  86         int eth_hdr_size;
  87
  88         switch (icmph->type) {
  89         case ICMP_ECHO_REPLY:
  90                 src_ip = net_read_ip((void *)&ip->ip_src);
  91                 if (src_ip.s_addr == net_ping_ip.s_addr)
  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_cond(DEBUG_DEV_PKT,
  98                            "Got ICMP ECHO REQUEST, return %d bytes\n",
  99                            eth_hdr_size + len);
 100
 101                 ip->ip_sum = 0;
 102                 ip->ip_off = 0;
 103                 net_copy_ip((void *)&ip->ip_dst, &ip->ip_src);
 104                 net_copy_ip((void *)&ip->ip_src, &net_ip);
 105                 ip->ip_sum = compute_ip_checksum(ip, IP_HDR_SIZE);
 106
 107                 icmph->type = ICMP_ECHO_REPLY;
 108                 icmph->checksum = 0;
 109                 icmph->checksum = compute_ip_checksum(icmph, len - IP_HDR_SIZE);
 110                 net_send_packet((uchar *)et, eth_hdr_size + len);
 111                 return;
 112 /*      default:
 113                 return;*/
 114         }
 115 }