xref: /OK3568_Linux_fs/u-boot/net/rarp.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * (C) Copyright 2000-2002
3*4882a593Smuzhiyun  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * SPDX-License-Identifier:	GPL-2.0+
6*4882a593Smuzhiyun  */
7*4882a593Smuzhiyun 
8*4882a593Smuzhiyun #include <common.h>
9*4882a593Smuzhiyun #include <command.h>
10*4882a593Smuzhiyun #include <net.h>
11*4882a593Smuzhiyun #include <net/tftp.h>
12*4882a593Smuzhiyun #include "nfs.h"
13*4882a593Smuzhiyun #include "bootp.h"
14*4882a593Smuzhiyun #include "rarp.h"
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun #define TIMEOUT 5000UL /* Milliseconds before trying BOOTP again */
17*4882a593Smuzhiyun #ifndef	CONFIG_NET_RETRY_COUNT
18*4882a593Smuzhiyun #define TIMEOUT_COUNT 5 /* # of timeouts before giving up  */
19*4882a593Smuzhiyun #else
20*4882a593Smuzhiyun #define TIMEOUT_COUNT (CONFIG_NET_RETRY_COUNT)
21*4882a593Smuzhiyun #endif
22*4882a593Smuzhiyun 
23*4882a593Smuzhiyun int rarp_try;
24*4882a593Smuzhiyun 
25*4882a593Smuzhiyun /*
26*4882a593Smuzhiyun  *	Handle a RARP received packet.
27*4882a593Smuzhiyun  */
rarp_receive(struct ip_udp_hdr * ip,unsigned len)28*4882a593Smuzhiyun void rarp_receive(struct ip_udp_hdr *ip, unsigned len)
29*4882a593Smuzhiyun {
30*4882a593Smuzhiyun 	struct arp_hdr *arp;
31*4882a593Smuzhiyun 
32*4882a593Smuzhiyun 	debug_cond(DEBUG_NET_PKT, "Got RARP\n");
33*4882a593Smuzhiyun 	arp = (struct arp_hdr *)ip;
34*4882a593Smuzhiyun 	if (len < ARP_HDR_SIZE) {
35*4882a593Smuzhiyun 		printf("bad length %d < %d\n", len, ARP_HDR_SIZE);
36*4882a593Smuzhiyun 		return;
37*4882a593Smuzhiyun 	}
38*4882a593Smuzhiyun 
39*4882a593Smuzhiyun 	if ((ntohs(arp->ar_op) != RARPOP_REPLY) ||
40*4882a593Smuzhiyun 	    (ntohs(arp->ar_hrd) != ARP_ETHER)   ||
41*4882a593Smuzhiyun 	    (ntohs(arp->ar_pro) != PROT_IP)     ||
42*4882a593Smuzhiyun 	    (arp->ar_hln != 6) || (arp->ar_pln != 4)) {
43*4882a593Smuzhiyun 		puts("invalid RARP header\n");
44*4882a593Smuzhiyun 	} else {
45*4882a593Smuzhiyun 		net_copy_ip(&net_ip, &arp->ar_data[16]);
46*4882a593Smuzhiyun 		if (net_server_ip.s_addr == 0)
47*4882a593Smuzhiyun 			net_copy_ip(&net_server_ip, &arp->ar_data[6]);
48*4882a593Smuzhiyun 		memcpy(net_server_ethaddr, &arp->ar_data[0], 6);
49*4882a593Smuzhiyun 		debug_cond(DEBUG_DEV_PKT, "Got good RARP\n");
50*4882a593Smuzhiyun 		net_auto_load();
51*4882a593Smuzhiyun 	}
52*4882a593Smuzhiyun }
53*4882a593Smuzhiyun 
54*4882a593Smuzhiyun 
55*4882a593Smuzhiyun /*
56*4882a593Smuzhiyun  *	Timeout on BOOTP request.
57*4882a593Smuzhiyun  */
rarp_timeout_handler(void)58*4882a593Smuzhiyun static void rarp_timeout_handler(void)
59*4882a593Smuzhiyun {
60*4882a593Smuzhiyun 	if (rarp_try >= TIMEOUT_COUNT) {
61*4882a593Smuzhiyun 		puts("\nRetry count exceeded; starting again\n");
62*4882a593Smuzhiyun 		net_start_again();
63*4882a593Smuzhiyun 	} else {
64*4882a593Smuzhiyun 		net_set_timeout_handler(TIMEOUT, rarp_timeout_handler);
65*4882a593Smuzhiyun 		rarp_request();
66*4882a593Smuzhiyun 	}
67*4882a593Smuzhiyun }
68*4882a593Smuzhiyun 
69*4882a593Smuzhiyun 
rarp_request(void)70*4882a593Smuzhiyun void rarp_request(void)
71*4882a593Smuzhiyun {
72*4882a593Smuzhiyun 	uchar *pkt;
73*4882a593Smuzhiyun 	struct arp_hdr *rarp;
74*4882a593Smuzhiyun 	int eth_hdr_size;
75*4882a593Smuzhiyun 
76*4882a593Smuzhiyun 	printf("RARP broadcast %d\n", ++rarp_try);
77*4882a593Smuzhiyun 	pkt = net_tx_packet;
78*4882a593Smuzhiyun 
79*4882a593Smuzhiyun 	eth_hdr_size = net_set_ether(pkt, net_bcast_ethaddr, PROT_RARP);
80*4882a593Smuzhiyun 	pkt += eth_hdr_size;
81*4882a593Smuzhiyun 
82*4882a593Smuzhiyun 	rarp = (struct arp_hdr *)pkt;
83*4882a593Smuzhiyun 
84*4882a593Smuzhiyun 	rarp->ar_hrd = htons(ARP_ETHER);
85*4882a593Smuzhiyun 	rarp->ar_pro = htons(PROT_IP);
86*4882a593Smuzhiyun 	rarp->ar_hln = 6;
87*4882a593Smuzhiyun 	rarp->ar_pln = 4;
88*4882a593Smuzhiyun 	rarp->ar_op  = htons(RARPOP_REQUEST);
89*4882a593Smuzhiyun 	memcpy(&rarp->ar_data[0],  net_ethaddr, 6);	/* source ET addr */
90*4882a593Smuzhiyun 	memcpy(&rarp->ar_data[6],  &net_ip,   4);	/* source IP addr */
91*4882a593Smuzhiyun 	/* dest ET addr = source ET addr ??*/
92*4882a593Smuzhiyun 	memcpy(&rarp->ar_data[10], net_ethaddr, 6);
93*4882a593Smuzhiyun 	/* dest IP addr set to broadcast */
94*4882a593Smuzhiyun 	memset(&rarp->ar_data[16], 0xff,        4);
95*4882a593Smuzhiyun 
96*4882a593Smuzhiyun 	net_send_packet(net_tx_packet, eth_hdr_size + ARP_HDR_SIZE);
97*4882a593Smuzhiyun 
98*4882a593Smuzhiyun 	net_set_timeout_handler(TIMEOUT, rarp_timeout_handler);
99*4882a593Smuzhiyun }
100