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-rw-r--r--net/arp.c213
1 files changed, 213 insertions, 0 deletions
diff --git a/net/arp.c b/net/arp.c
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index 0000000..f75217c
--- /dev/null
+++ b/net/arp.c
@@ -0,0 +1,213 @@
+/*
+ * 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
+ */
+
+#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;
+IPaddr_t NetArpWaitReplyIP;
+/* MAC address of waiting packet's destination */
+uchar *NetArpWaitPacketMAC;
+/* THE transmit packet */
+uchar *NetArpWaitTxPacket;
+int NetArpWaitTxPacketSize;
+uchar NetArpWaitPacketBuf[PKTSIZE_ALIGN + PKTALIGN];
+ulong NetArpWaitTimerStart;
+int NetArpWaitTry;
+
+void ArpInit(void)
+{
+ /* XXX problem with bss workaround */
+ NetArpWaitPacketMAC = NULL;
+ NetArpWaitPacketIP = 0;
+ NetArpWaitReplyIP = 0;
+ NetArpWaitTxPacket = &NetArpWaitPacketBuf[0] + (PKTALIGN - 1);
+ NetArpWaitTxPacket -= (ulong)NetArpWaitTxPacket % PKTALIGN;
+ NetArpWaitTxPacketSize = 0;
+}
+
+void ArpRequest(void)
+{
+ uchar *pkt;
+ ARP_t *arp;
+
+ debug("ARP broadcast %d\n", NetArpWaitTry);
+
+ pkt = NetTxPacket;
+
+ pkt += NetSetEther(pkt, NetBcastAddr, PROT_ARP);
+
+ arp = (ARP_t *) pkt;
+
+ arp->ar_hrd = htons(ARP_ETHER);
+ arp->ar_pro = htons(PROT_IP);
+ arp->ar_hln = 6;
+ arp->ar_pln = 4;
+ arp->ar_op = htons(ARPOP_REQUEST);
+
+ /* source ET addr */
+ memcpy(&arp->ar_data[0], NetOurEther, 6);
+ /* source IP addr */
+ NetWriteIP((uchar *) &arp->ar_data[6], NetOurIP);
+ /* dest ET addr = 0 */
+ memset(&arp->ar_data[10], '\0', 6);
+ if ((NetArpWaitPacketIP & NetOurSubnetMask) !=
+ (NetOurIP & NetOurSubnetMask)) {
+ if (NetOurGatewayIP == 0) {
+ puts("## Warning: gatewayip needed but not set\n");
+ NetArpWaitReplyIP = NetArpWaitPacketIP;
+ } else {
+ NetArpWaitReplyIP = NetOurGatewayIP;
+ }
+ } else {
+ NetArpWaitReplyIP = NetArpWaitPacketIP;
+ }
+
+ NetWriteIP((uchar *) &arp->ar_data[16], NetArpWaitReplyIP);
+ (void) eth_send(NetTxPacket, (pkt - NetTxPacket) + ARP_HDR_SIZE);
+}
+
+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(Ethernet_t *et, IP_t *ip, int len)
+{
+ ARP_t *arp;
+ IPaddr_t tmp;
+ uchar *pkt;
+
+ /*
+ * 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("Got ARP\n");
+
+ arp = (ARP_t *)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 != 6)
+ return;
+ if (arp->ar_pln != 4)
+ return;
+
+ if (NetOurIP == 0)
+ return;
+
+ if (NetReadIP(&arp->ar_data[16]) != NetOurIP)
+ return;
+
+ switch (ntohs(arp->ar_op)) {
+ case ARPOP_REQUEST:
+ /* reply with our IP address */
+ debug("Got ARP REQUEST, return our IP\n");
+ pkt = (uchar *)et;
+ pkt += NetSetEther(pkt, et->et_src, PROT_ARP);
+ arp->ar_op = htons(ARPOP_REPLY);
+ memcpy(&arp->ar_data[10], &arp->ar_data[0], 6);
+ NetCopyIP(&arp->ar_data[16], &arp->ar_data[6]);
+ memcpy(&arp->ar_data[0], NetOurEther, 6);
+ NetCopyIP(&arp->ar_data[6], &NetOurIP);
+ (void) eth_send((uchar *)et,
+ (pkt - (uchar *)et) + ARP_HDR_SIZE);
+ return;
+
+ case ARPOP_REPLY: /* arp reply */
+ /* are we waiting for a reply */
+ if (!NetArpWaitPacketIP || !NetArpWaitPacketMAC)
+ break;
+
+#ifdef CONFIG_KEEP_SERVERADDR
+ if (NetServerIP == NetArpWaitPacketIP) {
+ char buf[20];
+ sprintf(buf, "%pM", arp->ar_data);
+ setenv("serveraddr", buf);
+ }
+#endif
+
+ tmp = NetReadIP(&arp->ar_data[6]);
+
+ /* matched waiting packet's address */
+ if (tmp == NetArpWaitReplyIP) {
+ debug("Got ARP REPLY, set eth addr (%pM)\n",
+ arp->ar_data);
+
+ /* save address for later use */
+ memcpy(NetArpWaitPacketMAC,
+ &arp->ar_data[0], 6);
+
+#ifdef CONFIG_NETCONSOLE
+ NetGetHandler()(0, 0, 0, 0, 0);
+#endif
+ /* modify header, and transmit it */
+ memcpy(((Ethernet_t *)NetArpWaitTxPacket)->
+ et_dest, NetArpWaitPacketMAC, 6);
+ (void) eth_send(NetArpWaitTxPacket,
+ 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;
+ }
+}