2 * Copyright (c) 1992, 1993, 1994, 1995, 1996, 1997
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
8 * distributions including binary code include the above copyright notice and
9 * this paragraph in its entirety in the documentation or other materials
10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14 * the University nor the names of its contributors may be used to endorse
15 * or promote products derived from this software without specific prior
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
21 * Code by Gert Doering, SpaceNet GmbH, gert@space.net
23 * Reference documentation:
24 * http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm
28 static const char rcsid[] _U_ =
29 "@(#) $Header: /tcpdump/master/tcpdump/print-cdp.c,v 1.25 2004/10/07 14:53:11 hannes Exp $";
36 #include <tcpdump-stdinc.h>
41 #include "interface.h"
42 #include "addrtoname.h"
43 #include "extract.h" /* must come after interface.h */
46 #define CDP_HEADER_LEN 4
48 static struct tok cdp_tlv_values[] = {
52 { 0x04, "Capability"},
53 { 0x05, "Version String"},
56 { 0x08, "Protocol-Hello option"},
57 { 0x09, "VTP Management Domain"},
58 { 0x0a, "Native VLAN ID"},
60 { 0x0e, "ATA-186 VoIP VLAN request"},
61 { 0x0f, "ATA-186 VoIP VLAN assignment"},
62 { 0x10, "power consumption"},
64 { 0x12, "AVVID trust bitmap"},
65 { 0x13, "AVVID untrusted ports CoS"},
66 { 0x14, "System Name"},
67 { 0x15, "System Object ID (not decoded)"},
68 { 0x16, "Management Addresses"},
69 { 0x17, "Physical Location"},
73 static struct tok cdp_capability_values[] = {
75 { 0x02, "Transparent Bridge" },
76 { 0x04, "Source Route Bridge" },
77 { 0x08, "L2 Switch" },
78 { 0x10, "L3 capable" },
79 { 0x20, "IGMP snooping" },
80 { 0x40, "L1 capable" },
84 static int cdp_print_addr(const u_char *, int);
85 static int cdp_print_prefixes(const u_char *, int);
86 static unsigned long cdp_get_number(const u_char *, int);
89 cdp_print(const u_char *pptr, u_int length, u_int caplen)
94 if (caplen < CDP_HEADER_LEN) {
95 (void)printf("[|cdp]");
99 tptr = pptr; /* temporary pointer */
101 if (!TTEST2(*tptr, CDP_HEADER_LEN))
103 printf("CDPv%u, ttl: %us", *tptr, *(tptr+1));
105 printf(", checksum: %u (unverified), length %u", EXTRACT_16BITS(tptr), length);
106 tptr += CDP_HEADER_LEN;
108 while (tptr < (pptr+length)) {
110 if (!TTEST2(*tptr, 4)) /* read out Type and Length */
112 type = EXTRACT_16BITS(tptr);
113 len = EXTRACT_16BITS(tptr+2); /* object length includes the 4 bytes header length */
117 if (!TTEST2(*tptr, len))
120 if (vflag || type == 1) { /* in non-verbose mode just print Device-ID */
123 printf("\n\t%s (0x%02x), length: %u byte%s: ",
124 tok2str(cdp_tlv_values,"unknown field type", type),
127 len>1 ? "s" : ""); /* plural */
131 case 0x01: /* Device-ID */
133 printf(", Device-ID '%.*s'", len, tptr);
135 printf("'%.*s'", len, tptr);
137 case 0x02: /* Address */
138 if (cdp_print_addr(tptr, len) < 0)
141 case 0x03: /* Port-ID */
142 printf("'%.*s'", len, tptr);
144 case 0x04: /* Capabilities */
145 printf("(0x%08x): %s",
146 EXTRACT_32BITS(tptr),
147 bittok2str(cdp_capability_values, "none",EXTRACT_32BITS(tptr)));
149 case 0x05: /* Version */
151 for (i=0;i<len;i++) {
154 if (j == 0x0a) /* lets rework the version string to get a nice identation */
158 case 0x06: /* Platform */
159 printf("'%.*s'", len, tptr);
161 case 0x07: /* Prefixes */
162 if (cdp_print_prefixes(tptr, len) < 0)
165 case 0x08: /* Protocol Hello Option - not documented */
167 case 0x09: /* VTP Mgmt Domain - not documented */
168 printf("'%.*s'", len,tptr);
170 case 0x0a: /* Native VLAN ID - not documented */
171 printf("%d",EXTRACT_16BITS(tptr));
173 case 0x0b: /* Duplex - not documented */
174 printf("%s", *(tptr) ? "full": "half");
177 /* http://www.cisco.com/univercd/cc/td/doc/product/voice/ata/atarn/186rn21m.htm
178 * plus more details from other sources
180 case 0x0e: /* ATA-186 VoIP VLAN request - incomplete doc. */
181 printf("app %d, vlan %d",
182 *(tptr), EXTRACT_16BITS(tptr+1));
184 case 0x10: /* ATA-186 VoIP VLAN assignment - incomplete doc. */
186 cdp_get_number(tptr, len)/1000.0 );
188 case 0x11: /* MTU - not documented */
189 printf("%u bytes", EXTRACT_32BITS(tptr));
191 case 0x12: /* AVVID trust bitmap - not documented */
192 printf("0x%02x", *(tptr) );
194 case 0x13: /* AVVID untrusted port CoS - not documented */
195 printf("0x%02x", *(tptr));
197 case 0x14: /* System Name - not documented */
198 printf("'%.*s'", len, tptr);
200 case 0x16: /* System Object ID - not documented */
201 if (cdp_print_addr(tptr, len) < 0)
204 case 0x17: /* Physical Location - not documented */
205 printf("0x%02x/%.*s", *(tptr), len - 1, tptr + 1 );
208 print_unknown_data(tptr,"\n\t ",len);
212 /* avoid infinite loop */
218 printf(", length %u",caplen);
226 * Protocol type values.
228 * PT_NLPID means that the protocol type field contains an OSI NLPID.
230 * PT_IEEE_802_2 means that the protocol type field contains an IEEE 802.2
231 * LLC header that specifies that the payload is for that protocol.
233 #define PT_NLPID 1 /* OSI NLPID */
234 #define PT_IEEE_802_2 2 /* IEEE 802.2 LLC header */
237 cdp_print_addr(const u_char * p, int l)
240 const u_char *endp = p + l;
242 static u_char prot_ipv6[] = {
243 0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00, 0x86, 0xdd
248 num = EXTRACT_32BITS(p);
251 while (p < endp && num >= 0) {
255 pt = p[0]; /* type of "protocol" field */
256 pl = p[1]; /* length of "protocol" field */
260 if (p + pl + 2 > endp)
262 al = EXTRACT_16BITS(&p[pl]); /* address length */
264 if (pt == PT_NLPID && pl == 1 && *p == NLPID_IP && al == 4) {
266 * IPv4: protocol type = NLPID, protocol length = 1
267 * (1-byte NLPID), protocol = 0xcc (NLPID for IPv4),
275 printf("IPv4 (%u) %s",
281 else if (pt == PT_IEEE_802_2 && pl == 8 &&
282 memcmp(p, prot_ipv6, 8) == 0 && al == 16) {
284 * IPv6: protocol type = IEEE 802.2 header,
285 * protocol length = 8 (size of LLC+SNAP header),
286 * protocol = LLC+SNAP header with the IPv6
287 * Ethertype, address length = 16
294 printf("IPv6 (%u) %s",
302 * Generic case: just print raw data
307 printf("pt=0x%02x, pl=%d, pb=", *(p - 2), pl);
309 printf(" %02x", *p++);
313 al = (*p << 8) + *(p + 1);
314 printf(", al=%d, a=", al);
320 printf(" %02x", *p++);
335 cdp_print_prefixes(const u_char * p, int l)
340 printf(" IPv4 Prefixes (%d):", l / 5);
343 printf(" %u.%u.%u.%u/%u", p[0], p[1], p[2], p[3], p[4]);
354 /* read in a <n>-byte number, MSB first
355 * (of course this can handle max sizeof(long))
357 static unsigned long cdp_get_number(const u_char * p, int l)