net: Move ARP out of net.c

Separate this functionality out of the net.c behemoth Signed-off-by: Joe Hershberger <joe.hershberger@ni.com> Acked-by: Simon Glass <sjg@chromium.org> Acked-by: Mike Frysinger <vapier@gentoo.org>
2025-05-09 03:21:51 +00:00 · 2012-05-23 07:58:01 +00:00 · 2012-05-23 07:58:01 +00:00 · d280d3f430
commit d280d3f430
parent 1735188329
5 changed files with 259 additions and 197 deletions
--- a/net/arp.c
+++ 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;
+	}
+}