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-rw-r--r--net/cdp.c375
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();
+}
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