u-boot/net/arp.c
Wolfgang Denk 2ea9103924 SPDX License cleanup for LiMon imported files
A number of network related files were imported from the LiMon
project; these contain a somewhat unclear license statement:

	Copyright 1994 - 2000 Neil Russell.
	(See License)

I analyzed the source code of LiMon v1.4.2 which was used for this
import.  It does not contain any "License" file, but the top level
directory contains a file "COPYING", which turns out to be GPL v2
of June 1991.  So it is legitimate to conclude that the LiMon derived
files are also to be released under GPLv2.  Mark them as such.

Signed-off-by: Wolfgang Denk <wd@denx.de>
2014-10-10 09:44:43 -04:00

237 lines
5.8 KiB
C

/*
* Copied from Linux Monitor (LiMon) - Networking.
*
* Copyright 1994 - 2000 Neil Russell.
* (See License)
* Copyright 2000 Roland Borde
* Copyright 2000 Paolo Scaffardi
* Copyright 2000-2002 Wolfgang Denk, wd@denx.de
* SPDX-License-Identifier: GPL-2.0
*/
#include <common.h>
#include "arp.h"
#ifndef CONFIG_ARP_TIMEOUT
/* Milliseconds before trying ARP again */
# define ARP_TIMEOUT 5000UL
#else
# define ARP_TIMEOUT CONFIG_ARP_TIMEOUT
#endif
#ifndef CONFIG_NET_RETRY_COUNT
# define ARP_TIMEOUT_COUNT 5 /* # of timeouts before giving up */
#else
# define ARP_TIMEOUT_COUNT CONFIG_NET_RETRY_COUNT
#endif
IPaddr_t NetArpWaitPacketIP;
static IPaddr_t NetArpWaitReplyIP;
/* MAC address of waiting packet's destination */
uchar *NetArpWaitPacketMAC;
int NetArpWaitTxPacketSize;
ulong NetArpWaitTimerStart;
int NetArpWaitTry;
static uchar *NetArpTxPacket; /* THE ARP transmit packet */
static uchar NetArpPacketBuf[PKTSIZE_ALIGN + PKTALIGN];
void ArpInit(void)
{
/* XXX problem with bss workaround */
NetArpWaitPacketMAC = NULL;
NetArpWaitPacketIP = 0;
NetArpWaitReplyIP = 0;
NetArpWaitTxPacketSize = 0;
NetArpTxPacket = &NetArpPacketBuf[0] + (PKTALIGN - 1);
NetArpTxPacket -= (ulong)NetArpTxPacket % PKTALIGN;
}
void arp_raw_request(IPaddr_t sourceIP, const uchar *targetEther,
IPaddr_t targetIP)
{
uchar *pkt;
struct arp_hdr *arp;
int eth_hdr_size;
debug_cond(DEBUG_DEV_PKT, "ARP broadcast %d\n", NetArpWaitTry);
pkt = NetArpTxPacket;
eth_hdr_size = NetSetEther(pkt, NetBcastAddr, PROT_ARP);
pkt += eth_hdr_size;
arp = (struct arp_hdr *) pkt;
arp->ar_hrd = htons(ARP_ETHER);
arp->ar_pro = htons(PROT_IP);
arp->ar_hln = ARP_HLEN;
arp->ar_pln = ARP_PLEN;
arp->ar_op = htons(ARPOP_REQUEST);
memcpy(&arp->ar_sha, NetOurEther, ARP_HLEN); /* source ET addr */
NetWriteIP(&arp->ar_spa, sourceIP); /* source IP addr */
memcpy(&arp->ar_tha, targetEther, ARP_HLEN); /* target ET addr */
NetWriteIP(&arp->ar_tpa, targetIP); /* target IP addr */
NetSendPacket(NetArpTxPacket, eth_hdr_size + ARP_HDR_SIZE);
}
void ArpRequest(void)
{
if ((NetArpWaitPacketIP & NetOurSubnetMask) !=
(NetOurIP & NetOurSubnetMask)) {
if (NetOurGatewayIP == 0) {
puts("## Warning: gatewayip needed but not set\n");
NetArpWaitReplyIP = NetArpWaitPacketIP;
} else {
NetArpWaitReplyIP = NetOurGatewayIP;
}
} else {
NetArpWaitReplyIP = NetArpWaitPacketIP;
}
arp_raw_request(NetOurIP, NetEtherNullAddr, NetArpWaitReplyIP);
}
void ArpTimeoutCheck(void)
{
ulong t;
if (!NetArpWaitPacketIP)
return;
t = get_timer(0);
/* check for arp timeout */
if ((t - NetArpWaitTimerStart) > ARP_TIMEOUT) {
NetArpWaitTry++;
if (NetArpWaitTry >= ARP_TIMEOUT_COUNT) {
puts("\nARP Retry count exceeded; starting again\n");
NetArpWaitTry = 0;
NetStartAgain();
} else {
NetArpWaitTimerStart = t;
ArpRequest();
}
}
}
void ArpReceive(struct ethernet_hdr *et, struct ip_udp_hdr *ip, int len)
{
struct arp_hdr *arp;
IPaddr_t reply_ip_addr;
uchar *pkt;
int eth_hdr_size;
/*
* We have to deal with two types of ARP packets:
* - REQUEST packets will be answered by sending our
* IP address - if we know it.
* - REPLY packates are expected only after we asked
* for the TFTP server's or the gateway's ethernet
* address; so if we receive such a packet, we set
* the server ethernet address
*/
debug_cond(DEBUG_NET_PKT, "Got ARP\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_hrd) != ARP_ETHER)
return;
if (ntohs(arp->ar_pro) != PROT_IP)
return;
if (arp->ar_hln != ARP_HLEN)
return;
if (arp->ar_pln != ARP_PLEN)
return;
if (NetOurIP == 0)
return;
if (NetReadIP(&arp->ar_tpa) != NetOurIP)
return;
switch (ntohs(arp->ar_op)) {
case ARPOP_REQUEST:
/* reply with our IP address */
debug_cond(DEBUG_DEV_PKT, "Got ARP REQUEST, return our IP\n");
pkt = (uchar *)et;
eth_hdr_size = net_update_ether(et, et->et_src, PROT_ARP);
pkt += eth_hdr_size;
arp->ar_op = htons(ARPOP_REPLY);
memcpy(&arp->ar_tha, &arp->ar_sha, ARP_HLEN);
NetCopyIP(&arp->ar_tpa, &arp->ar_spa);
memcpy(&arp->ar_sha, NetOurEther, ARP_HLEN);
NetCopyIP(&arp->ar_spa, &NetOurIP);
#ifdef CONFIG_CMD_LINK_LOCAL
/*
* Work-around for brain-damaged Cisco equipment with
* arp-proxy enabled.
*
* If the requesting IP is not on our subnet, wait 5ms to
* reply to ARP request so that our reply will overwrite
* the arp-proxy's instead of the other way around.
*/
if ((NetReadIP(&arp->ar_tpa) & NetOurSubnetMask) !=
(NetReadIP(&arp->ar_spa) & NetOurSubnetMask))
udelay(5000);
#endif
NetSendPacket((uchar *)et, eth_hdr_size + ARP_HDR_SIZE);
return;
case ARPOP_REPLY: /* arp reply */
/* are we waiting for a reply */
if (!NetArpWaitPacketIP)
break;
#ifdef CONFIG_KEEP_SERVERADDR
if (NetServerIP == NetArpWaitPacketIP) {
char buf[20];
sprintf(buf, "%pM", &arp->ar_sha);
setenv("serveraddr", buf);
}
#endif
reply_ip_addr = NetReadIP(&arp->ar_spa);
/* matched waiting packet's address */
if (reply_ip_addr == NetArpWaitReplyIP) {
debug_cond(DEBUG_DEV_PKT,
"Got ARP REPLY, set eth addr (%pM)\n",
arp->ar_data);
/* save address for later use */
if (NetArpWaitPacketMAC != NULL)
memcpy(NetArpWaitPacketMAC,
&arp->ar_sha, ARP_HLEN);
net_get_arp_handler()((uchar *)arp, 0, reply_ip_addr,
0, len);
/* set the mac address in the waiting packet's header
and transmit it */
memcpy(((struct ethernet_hdr *)NetTxPacket)->et_dest,
&arp->ar_sha, ARP_HLEN);
NetSendPacket(NetTxPacket, NetArpWaitTxPacketSize);
/* no arp request pending now */
NetArpWaitPacketIP = 0;
NetArpWaitTxPacketSize = 0;
NetArpWaitPacketMAC = NULL;
}
return;
default:
debug("Unexpected ARP opcode 0x%x\n",
ntohs(arp->ar_op));
return;
}
}