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net: Fix parsing of Bootp/DHCP option 0 (Pad)
[people/ms/u-boot.git] / net / arp.c
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1/*
2 * Copied from Linux Monitor (LiMon) - Networking.
3 *
4 * Copyright 1994 - 2000 Neil Russell.
5 * (See License)
6 * Copyright 2000 Roland Borde
7 * Copyright 2000 Paolo Scaffardi
8 * Copyright 2000-2002 Wolfgang Denk, wd@denx.de
2ea91039 9 * SPDX-License-Identifier: GPL-2.0
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10 */
11
12#include <common.h>
13
14#include "arp.h"
15
16#ifndef CONFIG_ARP_TIMEOUT
17/* Milliseconds before trying ARP again */
18# define ARP_TIMEOUT 5000UL
19#else
20# define ARP_TIMEOUT CONFIG_ARP_TIMEOUT
21#endif
22
23
24#ifndef CONFIG_NET_RETRY_COUNT
25# define ARP_TIMEOUT_COUNT 5 /* # of timeouts before giving up */
26#else
27# define ARP_TIMEOUT_COUNT CONFIG_NET_RETRY_COUNT
28#endif
29
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30struct in_addr net_arp_wait_packet_ip;
31static struct in_addr net_arp_wait_reply_ip;
d280d3f4 32/* MAC address of waiting packet's destination */
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33uchar *arp_wait_packet_ethaddr;
34int arp_wait_tx_packet_size;
35ulong arp_wait_timer_start;
36int arp_wait_try;
d280d3f4 37
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38static uchar *arp_tx_packet; /* THE ARP transmit packet */
39static uchar arp_tx_packet_buf[PKTSIZE_ALIGN + PKTALIGN];
e94070c4 40
85d25e0e 41void arp_init(void)
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42{
43 /* XXX problem with bss workaround */
85d25e0e 44 arp_wait_packet_ethaddr = NULL;
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45 net_arp_wait_packet_ip.s_addr = 0;
46 net_arp_wait_reply_ip.s_addr = 0;
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47 arp_wait_tx_packet_size = 0;
48 arp_tx_packet = &arp_tx_packet_buf[0] + (PKTALIGN - 1);
49 arp_tx_packet -= (ulong)arp_tx_packet % PKTALIGN;
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50}
51
85d25e0e 52void arp_raw_request(struct in_addr source_ip, const uchar *target_ethaddr,
049a95a7 53 struct in_addr target_ip)
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54{
55 uchar *pkt;
738853bb 56 struct arp_hdr *arp;
00f33268 57 int eth_hdr_size;
d280d3f4 58
85d25e0e 59 debug_cond(DEBUG_DEV_PKT, "ARP broadcast %d\n", arp_wait_try);
d280d3f4 60
85d25e0e 61 pkt = arp_tx_packet;
d280d3f4 62
1203fcce 63 eth_hdr_size = net_set_ether(pkt, net_bcast_ethaddr, PROT_ARP);
00f33268 64 pkt += eth_hdr_size;
d280d3f4 65
85d25e0e 66 arp = (struct arp_hdr *)pkt;
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67
68 arp->ar_hrd = htons(ARP_ETHER);
69 arp->ar_pro = htons(PROT_IP);
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70 arp->ar_hln = ARP_HLEN;
71 arp->ar_pln = ARP_PLEN;
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72 arp->ar_op = htons(ARPOP_REQUEST);
73
0adb5b76 74 memcpy(&arp->ar_sha, net_ethaddr, ARP_HLEN); /* source ET addr */
049a95a7 75 net_write_ip(&arp->ar_spa, source_ip); /* source IP addr */
85d25e0e 76 memcpy(&arp->ar_tha, target_ethaddr, ARP_HLEN); /* target ET addr */
049a95a7 77 net_write_ip(&arp->ar_tpa, target_ip); /* target IP addr */
22804189 78
85d25e0e 79 net_send_packet(arp_tx_packet, eth_hdr_size + ARP_HDR_SIZE);
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80}
81
85d25e0e 82void arp_request(void)
22804189 83{
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84 if ((net_arp_wait_packet_ip.s_addr & net_netmask.s_addr) !=
85 (net_ip.s_addr & net_netmask.s_addr)) {
86 if (net_gateway.s_addr == 0) {
d280d3f4 87 puts("## Warning: gatewayip needed but not set\n");
049a95a7 88 net_arp_wait_reply_ip = net_arp_wait_packet_ip;
d280d3f4 89 } else {
049a95a7 90 net_arp_wait_reply_ip = net_gateway;
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91 }
92 } else {
049a95a7 93 net_arp_wait_reply_ip = net_arp_wait_packet_ip;
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94 }
95
0adb5b76 96 arp_raw_request(net_ip, net_null_ethaddr, net_arp_wait_reply_ip);
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97}
98
85d25e0e 99void arp_timeout_check(void)
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100{
101 ulong t;
102
049a95a7 103 if (!net_arp_wait_packet_ip.s_addr)
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104 return;
105
106 t = get_timer(0);
107
108 /* check for arp timeout */
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109 if ((t - arp_wait_timer_start) > ARP_TIMEOUT) {
110 arp_wait_try++;
d280d3f4 111
85d25e0e 112 if (arp_wait_try >= ARP_TIMEOUT_COUNT) {
d280d3f4 113 puts("\nARP Retry count exceeded; starting again\n");
85d25e0e 114 arp_wait_try = 0;
bc0571fc 115 net_start_again();
d280d3f4 116 } else {
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117 arp_wait_timer_start = t;
118 arp_request();
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119 }
120 }
121}
122
85d25e0e 123void arp_receive(struct ethernet_hdr *et, struct ip_udp_hdr *ip, int len)
d280d3f4 124{
738853bb 125 struct arp_hdr *arp;
049a95a7 126 struct in_addr reply_ip_addr;
d280d3f4 127 uchar *pkt;
00f33268 128 int eth_hdr_size;
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129
130 /*
131 * We have to deal with two types of ARP packets:
132 * - REQUEST packets will be answered by sending our
133 * IP address - if we know it.
134 * - REPLY packates are expected only after we asked
135 * for the TFTP server's or the gateway's ethernet
136 * address; so if we receive such a packet, we set
137 * the server ethernet address
138 */
4ef8d53c 139 debug_cond(DEBUG_NET_PKT, "Got ARP\n");
d280d3f4 140
738853bb 141 arp = (struct arp_hdr *)ip;
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142 if (len < ARP_HDR_SIZE) {
143 printf("bad length %d < %d\n", len, ARP_HDR_SIZE);
144 return;
145 }
146 if (ntohs(arp->ar_hrd) != ARP_ETHER)
147 return;
148 if (ntohs(arp->ar_pro) != PROT_IP)
149 return;
674bb249 150 if (arp->ar_hln != ARP_HLEN)
d280d3f4 151 return;
674bb249 152 if (arp->ar_pln != ARP_PLEN)
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153 return;
154
049a95a7 155 if (net_ip.s_addr == 0)
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156 return;
157
049a95a7 158 if (net_read_ip(&arp->ar_tpa).s_addr != net_ip.s_addr)
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159 return;
160
161 switch (ntohs(arp->ar_op)) {
162 case ARPOP_REQUEST:
163 /* reply with our IP address */
4ef8d53c 164 debug_cond(DEBUG_DEV_PKT, "Got ARP REQUEST, return our IP\n");
d280d3f4 165 pkt = (uchar *)et;
e7111015 166 eth_hdr_size = net_update_ether(et, et->et_src, PROT_ARP);
00f33268 167 pkt += eth_hdr_size;
d280d3f4 168 arp->ar_op = htons(ARPOP_REPLY);
674bb249 169 memcpy(&arp->ar_tha, &arp->ar_sha, ARP_HLEN);
049a95a7 170 net_copy_ip(&arp->ar_tpa, &arp->ar_spa);
0adb5b76 171 memcpy(&arp->ar_sha, net_ethaddr, ARP_HLEN);
049a95a7 172 net_copy_ip(&arp->ar_spa, &net_ip);
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173
174#ifdef CONFIG_CMD_LINK_LOCAL
175 /*
176 * Work-around for brain-damaged Cisco equipment with
177 * arp-proxy enabled.
178 *
179 * If the requesting IP is not on our subnet, wait 5ms to
180 * reply to ARP request so that our reply will overwrite
181 * the arp-proxy's instead of the other way around.
182 */
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183 if ((net_read_ip(&arp->ar_tpa).s_addr & net_netmask.s_addr) !=
184 (net_read_ip(&arp->ar_spa).s_addr & net_netmask.s_addr))
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185 udelay(5000);
186#endif
1203fcce 187 net_send_packet((uchar *)et, eth_hdr_size + ARP_HDR_SIZE);
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188 return;
189
190 case ARPOP_REPLY: /* arp reply */
191 /* are we waiting for a reply */
049a95a7 192 if (!net_arp_wait_packet_ip.s_addr)
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193 break;
194
195#ifdef CONFIG_KEEP_SERVERADDR
049a95a7 196 if (net_server_ip.s_addr == net_arp_wait_packet_ip.s_addr) {
d280d3f4 197 char buf[20];
a0bc44e6 198 sprintf(buf, "%pM", &arp->ar_sha);
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199 setenv("serveraddr", buf);
200 }
201#endif
202
049a95a7 203 reply_ip_addr = net_read_ip(&arp->ar_spa);
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204
205 /* matched waiting packet's address */
049a95a7 206 if (reply_ip_addr.s_addr == net_arp_wait_reply_ip.s_addr) {
4ef8d53c 207 debug_cond(DEBUG_DEV_PKT,
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208 "Got ARP REPLY, set eth addr (%pM)\n",
209 arp->ar_data);
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210
211 /* save address for later use */
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212 if (arp_wait_packet_ethaddr != NULL)
213 memcpy(arp_wait_packet_ethaddr,
f1d2d284 214 &arp->ar_sha, ARP_HLEN);
d280d3f4 215
ece223b5 216 net_get_arp_handler()((uchar *)arp, 0, reply_ip_addr,
85d25e0e 217 0, len);
ece223b5 218
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219 /* set the mac address in the waiting packet's header
220 and transmit it */
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221 memcpy(((struct ethernet_hdr *)net_tx_packet)->et_dest,
222 &arp->ar_sha, ARP_HLEN);
85d25e0e 223 net_send_packet(net_tx_packet, arp_wait_tx_packet_size);
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224
225 /* no arp request pending now */
049a95a7 226 net_arp_wait_packet_ip.s_addr = 0;
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227 arp_wait_tx_packet_size = 0;
228 arp_wait_packet_ethaddr = NULL;
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229 }
230 return;
231 default:
232 debug("Unexpected ARP opcode 0x%x\n",
233 ntohs(arp->ar_op));
234 return;
235 }
236}