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
23 int rarp_try;
24
25 /*
26 * Handle a RARP received packet.
27 */
rarp_receive(struct ip_udp_hdr * ip,unsigned len)28 void 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 */
rarp_timeout_handler(void)58 static 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
rarp_request(void)70 void 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