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