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 #include <net.h>
  15
  16 static ushort ping_seq_number;
  17
  18 /* The ip address to ping */
  19 struct in_addr net_ping_ip;
  20
  21 static void set_icmp_header(uchar *pkt, struct in_addr dest)
  22 {
  23         /*
  24          *      Construct an IP and ICMP header.
  25          */
  26         struct icmp_hdr *icmp = (struct icmp_hdr *)(pkt + IP_HDR_SIZE);
  27
  28         net_set_ip_header(pkt, dest, net_ip, IP_ICMP_HDR_SIZE, IPPROTO_ICMP);
  29
  30         icmp->type = ICMP_ECHO_REQUEST;
  31         icmp->code = 0;
  32         icmp->checksum = 0;
  33         icmp->un.echo.id = 0;
  34         icmp->un.echo.sequence = htons(ping_seq_number++);
  35         icmp->checksum = compute_ip_checksum(icmp, ICMP_HDR_SIZE);
  36 }
  37
  38 static int ping_send(void)
  39 {
  40         uchar *pkt;
  41         int eth_hdr_size;
  42
  43         /* XXX always send arp request */
  44
  45         debug_cond(DEBUG_DEV_PKT, "sending ARP for %pI4\n", &net_ping_ip);
  46
  47         net_arp_wait_packet_ip = net_ping_ip;
  48
  49         eth_hdr_size = net_set_ether(net_tx_packet, net_null_ethaddr, PROT_IP);
  50         pkt = (uchar *)net_tx_packet + eth_hdr_size;
  51
  52         set_icmp_header(pkt, net_ping_ip);
  53
  54         /* size of the waiting packet */
  55         arp_wait_tx_packet_size = eth_hdr_size + IP_ICMP_HDR_SIZE;
  56
  57         /* and do the ARP request */
  58         arp_wait_try = 1;
  59         arp_wait_timer_start = get_timer(0);
  60         arp_request();
  61         return 1;       /* waiting */
  62 }
  63
  64 static void ping_timeout_handler(void)
  65 {
  66         eth_halt();
  67         net_set_state(NETLOOP_FAIL);    /* we did not get the reply */
  68 }
  69
  70 void ping_start(void)
  71 {
  72         printf("Using %s device\n", eth_get_name());
  73         net_set_timeout_handler(10000UL, ping_timeout_handler);
  74
  75         ping_send();
  76 }
  77
  78 void ping_receive(struct ethernet_hdr *et, struct ip_udp_hdr *ip, int len)
  79 {
  80         struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src;
  81         struct in_addr src_ip;
  82         int eth_hdr_size;
  83         uchar *tx_packet;
  84
  85         switch (icmph->type) {
  86         case ICMP_ECHO_REPLY:
  87                 src_ip = net_read_ip((void *)&ip->ip_src);
  88                 if (src_ip.s_addr == net_ping_ip.s_addr)
  89                         net_set_state(NETLOOP_SUCCESS);
  90                 return;
  91         case ICMP_ECHO_REQUEST:
  92                 eth_hdr_size = net_update_ether(et, et->et_src, PROT_IP);
  93
  94                 debug_cond(DEBUG_DEV_PKT,
  95                            "Got ICMP ECHO REQUEST, return %d bytes\n",
  96                            eth_hdr_size + len);
  97
  98                 ip->ip_sum = 0;
  99                 ip->ip_off = 0;
 100                 net_copy_ip((void *)&ip->ip_dst, &ip->ip_src);
 101                 net_copy_ip((void *)&ip->ip_src, &net_ip);
 102                 ip->ip_sum = compute_ip_checksum(ip, IP_HDR_SIZE);
 103
 104                 icmph->type = ICMP_ECHO_REPLY;
 105                 icmph->checksum = 0;
 106                 icmph->checksum = compute_ip_checksum(icmph, len - IP_HDR_SIZE);
 107
 108                 tx_packet = net_get_async_tx_pkt_buf();
 109                 memcpy(tx_packet, et, eth_hdr_size + len);
 110                 net_send_packet(tx_packet, eth_hdr_size + len);
 111                 return;
 112 /*      default:
 113                 return;*/
 114         }
 115 }