LXR uboot/net/rarp.c

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * (C) Copyright 2000-2002
   4 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   5 */
   6
   7#include <common.h>
   8#include <command.h>
   9#include <log.h>
  10#include <net.h>
  11#include <net/tftp.h>
  12#include "nfs.h"
  13#include "bootp.h"
  14#include "rarp.h"
  15
  16#define TIMEOUT 5000UL /* Milliseconds before trying BOOTP again */
  17
  18int rarp_try;
  19
  20/*
  21 *      Handle a RARP received packet.
  22 */
  23void rarp_receive(struct ip_udp_hdr *ip, unsigned len)
  24{
  25        struct arp_hdr *arp;
  26
  27        debug_cond(DEBUG_NET_PKT, "Got RARP\n");
  28        arp = (struct arp_hdr *)ip;
  29        if (len < ARP_HDR_SIZE) {
  30                printf("bad length %d < %d\n", len, ARP_HDR_SIZE);
  31                return;
  32        }
  33
  34        if ((ntohs(arp->ar_op) != RARPOP_REPLY) ||
  35            (ntohs(arp->ar_hrd) != ARP_ETHER)   ||
  36            (ntohs(arp->ar_pro) != PROT_IP)     ||
  37            (arp->ar_hln != 6) || (arp->ar_pln != 4)) {
  38                puts("invalid RARP header\n");
  39        } else {
  40                net_copy_ip(&net_ip, &arp->ar_data[16]);
  41                if (net_server_ip.s_addr == 0)
  42                        net_copy_ip(&net_server_ip, &arp->ar_data[6]);
  43                memcpy(net_server_ethaddr, &arp->ar_data[0], 6);
  44                debug_cond(DEBUG_DEV_PKT, "Got good RARP\n");
  45                net_auto_load();
  46        }
  47}
  48
  49
  50/*
  51 *      Timeout on BOOTP request.
  52 */
  53static void rarp_timeout_handler(void)
  54{
  55        if (rarp_try >= CONFIG_NET_RETRY_COUNT) {
  56                puts("\nRetry count exceeded; starting again\n");
  57                net_start_again();
  58        } else {
  59                net_set_timeout_handler(TIMEOUT, rarp_timeout_handler);
  60                rarp_request();
  61        }
  62}
  63
  64
  65void rarp_request(void)
  66{
  67        uchar *pkt;
  68        struct arp_hdr *rarp;
  69        int eth_hdr_size;
  70
  71        printf("RARP broadcast %d\n", ++rarp_try);
  72        pkt = net_tx_packet;
  73
  74        eth_hdr_size = net_set_ether(pkt, net_bcast_ethaddr, PROT_RARP);
  75        pkt += eth_hdr_size;
  76
  77        rarp = (struct arp_hdr *)pkt;
  78
  79        rarp->ar_hrd = htons(ARP_ETHER);
  80        rarp->ar_pro = htons(PROT_IP);
  81        rarp->ar_hln = 6;
  82        rarp->ar_pln = 4;
  83        rarp->ar_op  = htons(RARPOP_REQUEST);
  84        memcpy(&rarp->ar_data[0],  net_ethaddr, 6);     /* source ET addr */
  85        memcpy(&rarp->ar_data[6],  &net_ip,   4);       /* source IP addr */
  86        /* dest ET addr = source ET addr ??*/
  87        memcpy(&rarp->ar_data[10], net_ethaddr, 6);
  88        /* dest IP addr set to broadcast */
  89        memset(&rarp->ar_data[16], 0xff,        4);
  90
  91        net_send_packet(net_tx_packet, eth_hdr_size + ARP_HDR_SIZE);
  92
  93        net_set_timeout_handler(TIMEOUT, rarp_timeout_handler);
  94}
  95