--- /dev/null
+/*
+ * Copyright (c) 1998-2007 The TCPDUMP project
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that: (1) source code
+ * distributions retain the above copyright notice and this paragraph
+ * in its entirety, and (2) distributions including binary code include
+ * the above copyright notice and this paragraph in its entirety in
+ * the documentation or other materials provided with the distribution.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
+ * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
+ * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE.
+ *
+ * UNIDIRECTIONAL LINK DETECTION (UDLD) as per
+ * http://www.ietf.org/internet-drafts/draft-foschiano-udld-02.txt
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <tcpdump-stdinc.h>
+
+#include <stdio.h>
+#include <string.h>
+
+#include "interface.h"
+#include "addrtoname.h"
+#include "extract.h"
+#include "nlpid.h"
+
+#define UDLD_HEADER_LEN 4
+#define UDLD_DEVICE_ID_TLV 0x0001
+#define UDLD_PORT_ID_TLV 0x0002
+#define UDLD_ECHO_TLV 0x0003
+#define UDLD_MESSAGE_INTERVAL_TLV 0x0004
+#define UDLD_TIMEOUT_INTERVAL_TLV 0x0005
+#define UDLD_DEVICE_NAME_TLV 0x0006
+#define UDLD_SEQ_NUMBER_TLV 0x0007
+
+static struct tok udld_tlv_values[] = {
+ { UDLD_DEVICE_ID_TLV, "Device-ID TLV"},
+ { UDLD_PORT_ID_TLV, "Port-ID TLV"},
+ { UDLD_ECHO_TLV, "Echo TLV"},
+ { UDLD_MESSAGE_INTERVAL_TLV, "Message Interval TLV"},
+ { UDLD_TIMEOUT_INTERVAL_TLV, "Timeout Interval TLV"},
+ { UDLD_DEVICE_NAME_TLV, "Device Name TLV"},
+ { UDLD_SEQ_NUMBER_TLV,"Sequence Number TLV"},
+ { 0, NULL}
+};
+
+static struct tok udld_code_values[] = {
+ { 0x00, "Reserved"},
+ { 0x01, "Probe message"},
+ { 0x02, "Echo message"},
+ { 0x03, "Flush message"},
+ { 0, NULL}
+};
+
+static struct tok udld_flags_values[] = {
+ { 0x00, "RT"},
+ { 0x01, "RSY"},
+ { 0, NULL}
+};
+
+/*
+ *
+ * 0 1 2 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | Ver | Opcode | Flags | Checksum |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | List of TLVs (variable length list) |
+ * | ... |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ */
+
+#define UDLD_EXTRACT_VERSION(x) (((x)&0xe0)>>5)
+#define UDLD_EXTRACT_OPCODE(x) ((x)&0x1f)
+
+void
+udld_print (const u_char *pptr, u_int length)
+{
+ int code, type, len;
+ const u_char *tptr;
+
+ if (length < UDLD_HEADER_LEN)
+ goto trunc;
+
+ tptr = pptr;
+
+ if (!TTEST2(*tptr, UDLD_HEADER_LEN))
+ goto trunc;
+
+ code = UDLD_EXTRACT_OPCODE(*tptr);
+
+ printf("UDLDv%u, Code %s (%x), Flags [%s] (0x%02x), length %u",
+ UDLD_EXTRACT_VERSION(*tptr),
+ tok2str(udld_code_values, "Reserved", code),
+ code,
+ bittok2str(udld_flags_values, "none", *(tptr+1)),
+ *(tptr+1),
+ length);
+
+ /*
+ * In non-verbose mode, just print version and opcode type
+ */
+ if (vflag < 1) {
+ return;
+ }
+
+ printf("\n\tChecksum 0x%04x (unverified)", EXTRACT_16BITS(tptr+2));
+
+ tptr += UDLD_HEADER_LEN;
+
+ while (tptr < (pptr+length)) {
+
+ if (!TTEST2(*tptr, 4))
+ goto trunc;
+
+ type = EXTRACT_16BITS(tptr);
+ len = EXTRACT_16BITS(tptr+2);
+ len -= 4;
+ tptr += 4;
+
+ /* infinite loop check */
+ if (type == 0 || len == 0) {
+ return;
+ }
+
+ printf("\n\t%s (0x%04x) TLV, length %u",
+ tok2str(udld_tlv_values, "Unknown", type),
+ type, len);
+
+ switch (type) {
+ case UDLD_DEVICE_ID_TLV:
+ case UDLD_PORT_ID_TLV:
+ case UDLD_ECHO_TLV:
+ case UDLD_DEVICE_NAME_TLV:
+ printf(", %s", tptr);
+ break;
+
+ case UDLD_MESSAGE_INTERVAL_TLV:
+ case UDLD_TIMEOUT_INTERVAL_TLV:
+ printf(", %us", (*tptr));
+ break;
+
+ case UDLD_SEQ_NUMBER_TLV:
+ printf(", %u", EXTRACT_32BITS(tptr));
+ break;
+
+ default:
+ break;
+ }
+ tptr += len;
+ }
+
+ return;
+
+ trunc:
+ printf("[|udld]");
+}
+
+/*
+ * Local Variables:
+ * c-style: whitesmith
+ * c-basic-offset: 4
+ * End:
+ */
projects / tcpdump / commitdiff
