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#ifndef CONFIG_NET_RETRY_COUNT
  18#define TIMEOUT_COUNT 5 /* # of timeouts before giving up  */
  19#else
  20#define TIMEOUT_COUNT (CONFIG_NET_RETRY_COUNT)
  21#endif
  22
  23int rarp_try;
  24
  25/*
  26 *      Handle a RARP received packet.
  27 */
  28void rarp_receive(struct ip_udp_hdr *ip, unsigned len)
  29{
  30        struct arp_hdr *arp;
  31
  32        debug_cond(DEBUG_NET_PKT, "Got RARP\n");
  33        arp = (struct arp_hdr *)ip;
  34        if (len < ARP_HDR_SIZE) {
  35                printf("bad length %d < %d\n", len, ARP_HDR_SIZE);
  36                return;
  37        }
  38
  39        if ((ntohs(arp->ar_op) != RARPOP_REPLY) ||
  40            (ntohs(arp->ar_hrd) != ARP_ETHER)   ||
  41            (ntohs(arp->ar_pro) != PROT_IP)     ||
  42            (arp->ar_hln != 6) || (arp->ar_pln != 4)) {
  43                puts("invalid RARP header\n");
  44        } else {
  45                net_copy_ip(&net_ip, &arp->ar_data[16]);
  46                if (net_server_ip.s_addr == 0)
  47                        net_copy_ip(&net_server_ip, &arp->ar_data[6]);
  48                memcpy(net_server_ethaddr, &arp->ar_data[0], 6);
  49                debug_cond(DEBUG_DEV_PKT, "Got good RARP\n");
  50                net_auto_load();
  51        }
  52}
  53
  54
  55/*
  56 *      Timeout on BOOTP request.
  57 */
  58static void rarp_timeout_handler(void)
  59{
  60        if (rarp_try >= TIMEOUT_COUNT) {
  61                puts("\nRetry count exceeded; starting again\n");
  62                net_start_again();
  63        } else {
  64                net_set_timeout_handler(TIMEOUT, rarp_timeout_handler);
  65                rarp_request();
  66        }
  67}
  68
  69
  70void rarp_request(void)
  71{
  72        uchar *pkt;
  73        struct arp_hdr *rarp;
  74        int eth_hdr_size;
  75
  76        printf("RARP broadcast %d\n", ++rarp_try);
  77        pkt = net_tx_packet;
  78
  79        eth_hdr_size = net_set_ether(pkt, net_bcast_ethaddr, PROT_RARP);
  80        pkt += eth_hdr_size;
  81
  82        rarp = (struct arp_hdr *)pkt;
  83
  84        rarp->ar_hrd = htons(ARP_ETHER);
  85        rarp->ar_pro = htons(PROT_IP);
  86        rarp->ar_hln = 6;
  87        rarp->ar_pln = 4;
  88        rarp->ar_op  = htons(RARPOP_REQUEST);
  89        memcpy(&rarp->ar_data[0],  net_ethaddr, 6);     /* source ET addr */
  90        memcpy(&rarp->ar_data[6],  &net_ip,   4);       /* source IP addr */
  91        /* dest ET addr = source ET addr ??*/
  92        memcpy(&rarp->ar_data[10], net_ethaddr, 6);
  93        /* dest IP addr set to broadcast */
  94        memset(&rarp->ar_data[16], 0xff,        4);
  95
  96        net_send_packet(net_tx_packet, eth_hdr_size + ARP_HDR_SIZE);
  97
  98        net_set_timeout_handler(TIMEOUT, rarp_timeout_handler);
  99}
 100