net/ping.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *      Copied from Linux Monitor (LiMon) - Networking.
   4  *
   5  *      Copyright 1994 - 2000 Neil Russell.
   6  *      (See License)
   7  *      Copyright 2000 Roland Borde
   8  *      Copyright 2000 Paolo Scaffardi
   9  *      Copyright 2000-2002 Wolfgang Denk, wd@denx.de
  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 icmp_hdr *icmp = (struct icmp_hdr *)(pkt + IP_HDR_SIZE);
  26
  27         net_set_ip_header(pkt, dest, net_ip, IP_ICMP_HDR_SIZE, IPPROTO_ICMP);
  28
  29         icmp->type = ICMP_ECHO_REQUEST;
  30         icmp->code = 0;
  31         icmp->checksum = 0;
  32         icmp->un.echo.id = 0;
  33         icmp->un.echo.sequence = htons(ping_seq_number++);
  34         icmp->checksum = compute_ip_checksum(icmp, ICMP_HDR_SIZE);
  35 }
  36
  37 static int ping_send(void)
  38 {
  39         uchar *pkt;
  40         int eth_hdr_size;
  41
  42         /* XXX always send arp request */
  43
  44         debug_cond(DEBUG_DEV_PKT, "sending ARP for %pI4\n", &net_ping_ip);
  45
  46         net_arp_wait_packet_ip = net_ping_ip;
  47
  48         eth_hdr_size = net_set_ether(net_tx_packet, net_null_ethaddr, PROT_IP);
  49         pkt = (uchar *)net_tx_packet + eth_hdr_size;
  50
  51         set_icmp_header(pkt, net_ping_ip);
  52
  53         /* size of the waiting packet */
  54         arp_wait_tx_packet_size = eth_hdr_size + IP_ICMP_HDR_SIZE;
  55
  56         /* and do the ARP request */
  57         arp_wait_try = 1;
  58         arp_wait_timer_start = get_timer(0);
  59         arp_request();
  60         return 1;       /* waiting */
  61 }
  62
  63 static void ping_timeout_handler(void)
  64 {
  65         eth_halt();
  66         net_set_state(NETLOOP_FAIL);    /* we did not get the reply */
  67 }
  68
  69 void ping_start(void)
  70 {
  71         printf("Using %s device\n", eth_get_name());
  72         net_set_timeout_handler(10000UL, ping_timeout_handler);
  73
  74         ping_send();
  75 }
  76
  77 void ping_receive(struct ethernet_hdr *et, struct ip_udp_hdr *ip, int len)
  78 {
  79         struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src;
  80         struct in_addr src_ip;
  81         int eth_hdr_size;
  82         uchar *tx_packet;
  83
  84         switch (icmph->type) {
  85         case ICMP_ECHO_REPLY:
  86                 src_ip = net_read_ip((void *)&ip->ip_src);
  87                 if (src_ip.s_addr == net_ping_ip.s_addr)
  88                         net_set_state(NETLOOP_SUCCESS);
  89                 return;
  90         case ICMP_ECHO_REQUEST:
  91                 eth_hdr_size = net_update_ether(et, et->et_src, PROT_IP);
  92
  93                 debug_cond(DEBUG_DEV_PKT,
  94                            "Got ICMP ECHO REQUEST, return %d bytes\n",
  95                            eth_hdr_size + len);
  96
  97                 ip->ip_sum = 0;
  98                 ip->ip_off = 0;
  99                 net_copy_ip((void *)&ip->ip_dst, &ip->ip_src);
 100                 net_copy_ip((void *)&ip->ip_src, &net_ip);
 101                 ip->ip_sum = compute_ip_checksum(ip, IP_HDR_SIZE);
 102
 103                 icmph->type = ICMP_ECHO_REPLY;
 104                 icmph->checksum = 0;
 105                 icmph->checksum = compute_ip_checksum(icmph, len - IP_HDR_SIZE);
 106
 107                 tx_packet = net_get_async_tx_pkt_buf();
 108                 memcpy(tx_packet, et, eth_hdr_size + len);
 109                 net_send_packet(tx_packet, eth_hdr_size + len);
 110                 return;
 111 /*      default:
 112                 return;*/
 113         }
 114 }