rarp.c
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/*
* (C) Copyright 2000-2002
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <command.h>
#include <net.h>
#include "nfs.h"
#include "bootp.h"
#include "rarp.h"
#include "tftp.h"
#define TIMEOUT 5000UL /* Milliseconds before trying BOOTP again */
#ifndef CONFIG_NET_RETRY_COUNT
#define TIMEOUT_COUNT 5 /* # of timeouts before giving up */
#else
#define TIMEOUT_COUNT (CONFIG_NET_RETRY_COUNT)
#endif
int RarpTry;
/*
* Handle a RARP received packet.
*/
void rarp_receive(struct ip_udp_hdr *ip, unsigned len)
{
struct arp_hdr *arp;
debug_cond(DEBUG_NET_PKT, "Got RARP\n");
arp = (struct arp_hdr *)ip;
if (len < ARP_HDR_SIZE) {
printf("bad length %d < %d\n", len, ARP_HDR_SIZE);
return;
}
if ((ntohs(arp->ar_op) != RARPOP_REPLY) ||
(ntohs(arp->ar_hrd) != ARP_ETHER) ||
(ntohs(arp->ar_pro) != PROT_IP) ||
(arp->ar_hln != 6) || (arp->ar_pln != 4)) {
puts("invalid RARP header\n");
} else {
NetCopyIP(&NetOurIP, &arp->ar_data[16]);
if (NetServerIP == 0)
NetCopyIP(&NetServerIP, &arp->ar_data[6]);
memcpy(NetServerEther, &arp->ar_data[0], 6);
debug_cond(DEBUG_DEV_PKT, "Got good RARP\n");
net_auto_load();
}
}
/*
* Timeout on BOOTP request.
*/
static void RarpTimeout(void)
{
if (RarpTry >= TIMEOUT_COUNT) {
puts("\nRetry count exceeded; starting again\n");
NetStartAgain();
} else {
NetSetTimeout(TIMEOUT, RarpTimeout);
RarpRequest();
}
}
void RarpRequest(void)
{
uchar *pkt;
struct arp_hdr *rarp;
int eth_hdr_size;
printf("RARP broadcast %d\n", ++RarpTry);
pkt = NetTxPacket;
eth_hdr_size = NetSetEther(pkt, NetBcastAddr, PROT_RARP);
pkt += eth_hdr_size;
rarp = (struct arp_hdr *)pkt;
rarp->ar_hrd = htons(ARP_ETHER);
rarp->ar_pro = htons(PROT_IP);
rarp->ar_hln = 6;
rarp->ar_pln = 4;
rarp->ar_op = htons(RARPOP_REQUEST);
memcpy(&rarp->ar_data[0], NetOurEther, 6); /* source ET addr */
memcpy(&rarp->ar_data[6], &NetOurIP, 4); /* source IP addr */
/* dest ET addr = source ET addr ??*/
memcpy(&rarp->ar_data[10], NetOurEther, 6);
/* dest IP addr set to broadcast */
memset(&rarp->ar_data[16], 0xff, 4);
NetSendPacket(NetTxPacket, eth_hdr_size + ARP_HDR_SIZE);
NetSetTimeout(TIMEOUT, RarpTimeout);
}