net: Move CDP out of net.c

Separate this functionality out of the net.c behemoth

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>

1 files changed, 375 insertions, 0 deletions

diff --git a/net/cdp.c b/net/cdp.c
new file mode 100644
index 0000000..004aae2
--- /dev/null
+++ b/net/cdp.c
@@ -0,0 +1,375 @@
+/*
+ *	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 <net.h>
+#if defined(CONFIG_CDP_VERSION)
+#include <timestamp.h>
+#endif
+
+#include "cdp.h"
+
+/* Ethernet bcast address */
+const uchar NetCDPAddr[6] = { 0x01, 0x00, 0x0c, 0xcc, 0xcc, 0xcc };
+
+#define CDP_DEVICE_ID_TLV		0x0001
+#define CDP_ADDRESS_TLV			0x0002
+#define CDP_PORT_ID_TLV			0x0003
+#define CDP_CAPABILITIES_TLV		0x0004
+#define CDP_VERSION_TLV			0x0005
+#define CDP_PLATFORM_TLV		0x0006
+#define CDP_NATIVE_VLAN_TLV		0x000a
+#define CDP_APPLIANCE_VLAN_TLV		0x000e
+#define CDP_TRIGGER_TLV			0x000f
+#define CDP_POWER_CONSUMPTION_TLV	0x0010
+#define CDP_SYSNAME_TLV			0x0014
+#define CDP_SYSOBJECT_TLV		0x0015
+#define CDP_MANAGEMENT_ADDRESS_TLV	0x0016
+
+#define CDP_TIMEOUT			250UL	/* one packet every 250ms */
+
+static int CDPSeq;
+static int CDPOK;
+
+ushort CDPNativeVLAN;
+ushort CDPApplianceVLAN;
+
+static const uchar CDP_SNAP_hdr[8] = {
+	0xAA, 0xAA, 0x03, 0x00, 0x00, 0x0C, 0x20, 0x00 };
+
+static ushort
+CDP_compute_csum(const uchar *buff, ushort len)
+{
+	ushort csum;
+	int     odd;
+	ulong   result = 0;
+	ushort  leftover;
+	ushort *p;
+
+	if (len > 0) {
+		odd = 1 & (ulong)buff;
+		if (odd) {
+			result = *buff << 8;
+			len--;
+			buff++;
+		}
+		while (len > 1) {
+			p = (ushort *)buff;
+			result += *p++;
+			buff = (uchar *)p;
+			if (result & 0x80000000)
+				result = (result & 0xFFFF) + (result >> 16);
+			len -= 2;
+		}
+		if (len) {
+			leftover = (signed short)(*(const signed char *)buff);
+			/*
+			 * CISCO SUCKS big time! (and blows too):
+			 * CDP uses the IP checksum algorithm with a twist;
+			 * for the last byte it *sign* extends and sums.
+			 */
+			result = (result & 0xffff0000) |
+				 ((result + leftover) & 0x0000ffff);
+		}
+		while (result >> 16)
+			result = (result & 0xFFFF) + (result >> 16);
+
+		if (odd)
+			result = ((result >> 8) & 0xff) |
+				 ((result & 0xff) << 8);
+	}
+
+	/* add up 16-bit and 17-bit words for 17+c bits */
+	result = (result & 0xffff) + (result >> 16);
+	/* add up 16-bit and 2-bit for 16+c bit */
+	result = (result & 0xffff) + (result >> 16);
+	/* add up carry.. */
+	result = (result & 0xffff) + (result >> 16);
+
+	/* negate */
+	csum = ~(ushort)result;
+
+	/* run time endian detection */
+	if (csum != htons(csum))	/* little endian */
+		csum = htons(csum);
+
+	return csum;
+}
+
+static int
+CDPSendTrigger(void)
+{
+	uchar *pkt;
+	ushort *s;
+	ushort *cp;
+	Ethernet_t *et;
+	int len;
+	ushort chksum;
+#if	defined(CONFIG_CDP_DEVICE_ID) || defined(CONFIG_CDP_PORT_ID)   || \
+	defined(CONFIG_CDP_VERSION)   || defined(CONFIG_CDP_PLATFORM)
+	char buf[32];
+#endif
+
+	pkt = NetTxPacket;
+	et = (Ethernet_t *)pkt;
+
+	/* NOTE: trigger sent not on any VLAN */
+
+	/* form ethernet header */
+	memcpy(et->et_dest, NetCDPAddr, 6);
+	memcpy(et->et_src, NetOurEther, 6);
+
+	pkt += ETHER_HDR_SIZE;
+
+	/* SNAP header */
+	memcpy((uchar *)pkt, CDP_SNAP_hdr, sizeof(CDP_SNAP_hdr));
+	pkt += sizeof(CDP_SNAP_hdr);
+
+	/* CDP header */
+	*pkt++ = 0x02;				/* CDP version 2 */
+	*pkt++ = 180;				/* TTL */
+	s = (ushort *)pkt;
+	cp = s;
+	/* checksum (0 for later calculation) */
+	*s++ = htons(0);
+
+	/* CDP fields */
+#ifdef CONFIG_CDP_DEVICE_ID
+	*s++ = htons(CDP_DEVICE_ID_TLV);
+	*s++ = htons(CONFIG_CDP_DEVICE_ID);
+	sprintf(buf, CONFIG_CDP_DEVICE_ID_PREFIX "%pm", NetOurEther);
+	memcpy((uchar *)s, buf, 16);
+	s += 16 / 2;
+#endif
+
+#ifdef CONFIG_CDP_PORT_ID
+	*s++ = htons(CDP_PORT_ID_TLV);
+	memset(buf, 0, sizeof(buf));
+	sprintf(buf, CONFIG_CDP_PORT_ID, eth_get_dev_index());
+	len = strlen(buf);
+	if (len & 1)	/* make it even */
+		len++;
+	*s++ = htons(len + 4);
+	memcpy((uchar *)s, buf, len);
+	s += len / 2;
+#endif
+
+#ifdef CONFIG_CDP_CAPABILITIES
+	*s++ = htons(CDP_CAPABILITIES_TLV);
+	*s++ = htons(8);
+	*(ulong *)s = htonl(CONFIG_CDP_CAPABILITIES);
+	s += 2;
+#endif
+
+#ifdef CONFIG_CDP_VERSION
+	*s++ = htons(CDP_VERSION_TLV);
+	memset(buf, 0, sizeof(buf));
+	strcpy(buf, CONFIG_CDP_VERSION);
+	len = strlen(buf);
+	if (len & 1)	/* make it even */
+		len++;
+	*s++ = htons(len + 4);
+	memcpy((uchar *)s, buf, len);
+	s += len / 2;
+#endif
+
+#ifdef CONFIG_CDP_PLATFORM
+	*s++ = htons(CDP_PLATFORM_TLV);
+	memset(buf, 0, sizeof(buf));
+	strcpy(buf, CONFIG_CDP_PLATFORM);
+	len = strlen(buf);
+	if (len & 1)	/* make it even */
+		len++;
+	*s++ = htons(len + 4);
+	memcpy((uchar *)s, buf, len);
+	s += len / 2;
+#endif
+
+#ifdef CONFIG_CDP_TRIGGER
+	*s++ = htons(CDP_TRIGGER_TLV);
+	*s++ = htons(8);
+	*(ulong *)s = htonl(CONFIG_CDP_TRIGGER);
+	s += 2;
+#endif
+
+#ifdef CONFIG_CDP_POWER_CONSUMPTION
+	*s++ = htons(CDP_POWER_CONSUMPTION_TLV);
+	*s++ = htons(6);
+	*s++ = htons(CONFIG_CDP_POWER_CONSUMPTION);
+#endif
+
+	/* length of ethernet packet */
+	len = (uchar *)s - ((uchar *)NetTxPacket + ETHER_HDR_SIZE);
+	et->et_protlen = htons(len);
+
+	len = ETHER_HDR_SIZE + sizeof(CDP_SNAP_hdr);
+	chksum = CDP_compute_csum((uchar *)NetTxPacket + len,
+				  (uchar *)s - (NetTxPacket + len));
+	if (chksum == 0)
+		chksum = 0xFFFF;
+	*cp = htons(chksum);
+
+	(void) eth_send(NetTxPacket, (uchar *)s - NetTxPacket);
+	return 0;
+}
+
+static void
+CDPTimeout(void)
+{
+	CDPSeq++;
+
+	if (CDPSeq < 3) {
+		NetSetTimeout(CDP_TIMEOUT, CDPTimeout);
+		CDPSendTrigger();
+		return;
+	}
+
+	/* if not OK try again */
+	if (!CDPOK)
+		NetStartAgain();
+	else
+		NetState = NETLOOP_SUCCESS;
+}
+
+static void
+CDPDummyHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src,
+		unsigned len)
+{
+	/* nothing */
+}
+
+void
+CDPHandler(const uchar *pkt, unsigned len)
+{
+	const uchar *t;
+	const ushort *ss;
+	ushort type, tlen;
+	ushort vlan, nvlan;
+
+	/* minimum size? */
+	if (len < sizeof(CDP_SNAP_hdr) + 4)
+		goto pkt_short;
+
+	/* check for valid CDP SNAP header */
+	if (memcmp(pkt, CDP_SNAP_hdr, sizeof(CDP_SNAP_hdr)) != 0)
+		return;
+
+	pkt += sizeof(CDP_SNAP_hdr);
+	len -= sizeof(CDP_SNAP_hdr);
+
+	/* Version of CDP protocol must be >= 2 and TTL != 0 */
+	if (pkt[0] < 0x02 || pkt[1] == 0)
+		return;
+
+	/*
+	 * if version is greater than 0x02 maybe we'll have a problem;
+	 * output a warning
+	 */
+	if (pkt[0] != 0x02)
+		printf("**WARNING: CDP packet received with a protocol version "
+				"%d > 2\n", pkt[0] & 0xff);
+
+	if (CDP_compute_csum(pkt, len) != 0)
+		return;
+
+	pkt += 4;
+	len -= 4;
+
+	vlan = htons(-1);
+	nvlan = htons(-1);
+	while (len > 0) {
+		if (len < 4)
+			goto pkt_short;
+
+		ss = (const ushort *)pkt;
+		type = ntohs(ss[0]);
+		tlen = ntohs(ss[1]);
+		if (tlen > len)
+			goto pkt_short;
+
+		pkt += tlen;
+		len -= tlen;
+
+		ss += 2;	/* point ss to the data of the TLV */
+		tlen -= 4;
+
+		switch (type) {
+		case CDP_DEVICE_ID_TLV:
+			break;
+		case CDP_ADDRESS_TLV:
+			break;
+		case CDP_PORT_ID_TLV:
+			break;
+		case CDP_CAPABILITIES_TLV:
+			break;
+		case CDP_VERSION_TLV:
+			break;
+		case CDP_PLATFORM_TLV:
+			break;
+		case CDP_NATIVE_VLAN_TLV:
+			nvlan = *ss;
+			break;
+		case CDP_APPLIANCE_VLAN_TLV:
+			t = (const uchar *)ss;
+			while (tlen > 0) {
+				if (tlen < 3)
+					goto pkt_short;
+
+				ss = (const ushort *)(t + 1);
+
+#ifdef CONFIG_CDP_APPLIANCE_VLAN_TYPE
+				if (t[0] == CONFIG_CDP_APPLIANCE_VLAN_TYPE)
+					vlan = *ss;
+#else
+				/* XXX will this work; dunno */
+				vlan = ntohs(*ss);
+#endif
+				t += 3; tlen -= 3;
+			}
+			break;
+		case CDP_TRIGGER_TLV:
+			break;
+		case CDP_POWER_CONSUMPTION_TLV:
+			break;
+		case CDP_SYSNAME_TLV:
+			break;
+		case CDP_SYSOBJECT_TLV:
+			break;
+		case CDP_MANAGEMENT_ADDRESS_TLV:
+			break;
+		}
+	}
+
+	CDPApplianceVLAN = vlan;
+	CDPNativeVLAN = nvlan;
+
+	CDPOK = 1;
+	return;
+
+ pkt_short:
+	printf("** CDP packet is too short\n");
+	return;
+}
+
+void
+CDPStart(void)
+{
+	printf("Using %s device\n", eth_get_name());
+	CDPSeq = 0;
+	CDPOK = 0;
+
+	CDPNativeVLAN = htons(-1);
+	CDPApplianceVLAN = htons(-1);
+
+	NetSetTimeout(CDP_TIMEOUT, CDPTimeout);
+	NetSetHandler(CDPDummyHandler);
+
+	CDPSendTrigger();
+}