xref: /freebsd/contrib/tcpdump/print-ether.c (revision aa64588d28258aef88cc33b8043112e8856948d0)
1 /*
2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000
3  *	The Regents of the University of California.  All rights reserved.
4  *
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
16  * written permission.
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.
20  *
21  * $FreeBSD$
22  */
23 #ifndef lint
24 static const char rcsid[] _U_ =
25     "@(#) $Header: /tcpdump/master/tcpdump/print-ether.c,v 1.105.2.1 2008-02-06 10:49:22 guy Exp $ (LBL)";
26 #endif
27 
28 #ifdef HAVE_CONFIG_H
29 #include "config.h"
30 #endif
31 
32 #include <tcpdump-stdinc.h>
33 
34 #include <stdio.h>
35 #include <pcap.h>
36 
37 #include "interface.h"
38 #include "addrtoname.h"
39 #include "ethertype.h"
40 
41 #include "ether.h"
42 
43 const struct tok ethertype_values[] = {
44     { ETHERTYPE_IP,		"IPv4" },
45     { ETHERTYPE_MPLS,		"MPLS unicast" },
46     { ETHERTYPE_MPLS_MULTI,	"MPLS multicast" },
47     { ETHERTYPE_IPV6,		"IPv6" },
48     { ETHERTYPE_8021Q,		"802.1Q" },
49     { ETHERTYPE_VMAN,		"VMAN" },
50     { ETHERTYPE_PUP,            "PUP" },
51     { ETHERTYPE_ARP,            "ARP"},
52     { ETHERTYPE_REVARP,         "Reverse ARP"},
53     { ETHERTYPE_NS,             "NS" },
54     { ETHERTYPE_SPRITE,         "Sprite" },
55     { ETHERTYPE_TRAIL,          "Trail" },
56     { ETHERTYPE_MOPDL,          "MOP DL" },
57     { ETHERTYPE_MOPRC,          "MOP RC" },
58     { ETHERTYPE_DN,             "DN" },
59     { ETHERTYPE_LAT,            "LAT" },
60     { ETHERTYPE_SCA,            "SCA" },
61     { ETHERTYPE_LANBRIDGE,      "Lanbridge" },
62     { ETHERTYPE_DECDNS,         "DEC DNS" },
63     { ETHERTYPE_DECDTS,         "DEC DTS" },
64     { ETHERTYPE_VEXP,           "VEXP" },
65     { ETHERTYPE_VPROD,          "VPROD" },
66     { ETHERTYPE_ATALK,          "Appletalk" },
67     { ETHERTYPE_AARP,           "Appletalk ARP" },
68     { ETHERTYPE_IPX,            "IPX" },
69     { ETHERTYPE_PPP,            "PPP" },
70     { ETHERTYPE_MPCP,           "MPCP" },
71     { ETHERTYPE_SLOW,           "Slow Protocols" },
72     { ETHERTYPE_PPPOED,         "PPPoE D" },
73     { ETHERTYPE_PPPOES,         "PPPoE S" },
74     { ETHERTYPE_EAPOL,          "EAPOL" },
75     { ETHERTYPE_RRCP,           "RRCP" },
76     { ETHERTYPE_JUMBO,          "Jumbo" },
77     { ETHERTYPE_LOOPBACK,       "Loopback" },
78     { ETHERTYPE_ISO,            "OSI" },
79     { ETHERTYPE_GRE_ISO,        "GRE-OSI" },
80     { ETHERTYPE_CFM_OLD,        "CFM (old)" },
81     { ETHERTYPE_CFM,            "CFM" },
82     { ETHERTYPE_LLDP,           "LLDP" },
83     { 0, NULL}
84 };
85 
86 static inline void
87 ether_hdr_print(register const u_char *bp, u_int length)
88 {
89 	register const struct ether_header *ep;
90 	ep = (const struct ether_header *)bp;
91 
92 	(void)printf("%s > %s",
93 		     etheraddr_string(ESRC(ep)),
94 		     etheraddr_string(EDST(ep)));
95 
96 	if (!qflag) {
97 	        if (ntohs(ep->ether_type) <= ETHERMTU)
98 		          (void)printf(", 802.3");
99                 else
100 		          (void)printf(", ethertype %s (0x%04x)",
101 				       tok2str(ethertype_values,"Unknown", ntohs(ep->ether_type)),
102                                        ntohs(ep->ether_type));
103         } else {
104                 if (ntohs(ep->ether_type) <= ETHERMTU)
105                           (void)printf(", 802.3");
106                 else
107                           (void)printf(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", ntohs(ep->ether_type)));
108         }
109 
110 	(void)printf(", length %u: ", length);
111 }
112 
113 void
114 ether_print(const u_char *p, u_int length, u_int caplen)
115 {
116 	struct ether_header *ep;
117 	u_short ether_type;
118 	u_short extracted_ether_type;
119 
120 	if (caplen < ETHER_HDRLEN) {
121 		printf("[|ether]");
122 		return;
123 	}
124 
125 	if (eflag)
126 		ether_hdr_print(p, length);
127 
128 	length -= ETHER_HDRLEN;
129 	caplen -= ETHER_HDRLEN;
130 	ep = (struct ether_header *)p;
131 	p += ETHER_HDRLEN;
132 
133 	ether_type = ntohs(ep->ether_type);
134 
135 	/*
136 	 * Is it (gag) an 802.3 encapsulation?
137 	 */
138 	if (ether_type <= ETHERMTU) {
139 		/* Try to print the LLC-layer header & higher layers */
140 		if (llc_print(p, length, caplen, ESRC(ep), EDST(ep),
141 		    &extracted_ether_type) == 0) {
142 			/* ether_type not known, print raw packet */
143 			if (!eflag)
144 				ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
145 
146 			if (!suppress_default_print)
147 				default_print(p, caplen);
148 		}
149 	} else if (ether_encap_print(ether_type, p, length, caplen,
150 	    &extracted_ether_type) == 0) {
151 		/* ether_type not known, print raw packet */
152 		if (!eflag)
153 			ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
154 
155 		if (!suppress_default_print)
156 			default_print(p, caplen);
157 	}
158 }
159 
160 /*
161  * This is the top level routine of the printer.  'p' points
162  * to the ether header of the packet, 'h->ts' is the timestamp,
163  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
164  * is the number of bytes actually captured.
165  */
166 u_int
167 ether_if_print(const struct pcap_pkthdr *h, const u_char *p)
168 {
169 	ether_print(p, h->len, h->caplen);
170 
171 	return (ETHER_HDRLEN);
172 }
173 
174 /*
175  * Prints the packet encapsulated in an Ethernet data segment
176  * (or an equivalent encapsulation), given the Ethernet type code.
177  *
178  * Returns non-zero if it can do so, zero if the ethertype is unknown.
179  *
180  * The Ethernet type code is passed through a pointer; if it was
181  * ETHERTYPE_8021Q, it gets updated to be the Ethernet type of
182  * the 802.1Q payload, for the benefit of lower layers that might
183  * want to know what it is.
184  */
185 
186 int
187 ether_encap_print(u_short ether_type, const u_char *p,
188     u_int length, u_int caplen, u_short *extracted_ether_type)
189 {
190  recurse:
191 	*extracted_ether_type = ether_type;
192 
193 	switch (ether_type) {
194 
195 	case ETHERTYPE_IP:
196 	        ip_print(gndo, p, length);
197 		return (1);
198 
199 #ifdef INET6
200 	case ETHERTYPE_IPV6:
201 		ip6_print(p, length);
202 		return (1);
203 #endif /*INET6*/
204 
205 	case ETHERTYPE_ARP:
206 	case ETHERTYPE_REVARP:
207   	        arp_print(gndo, p, length, caplen);
208 		return (1);
209 
210 	case ETHERTYPE_DN:
211 		decnet_print(p, length, caplen);
212 		return (1);
213 
214 	case ETHERTYPE_ATALK:
215 		if (vflag)
216 			fputs("et1 ", stdout);
217 		atalk_print(p, length);
218 		return (1);
219 
220 	case ETHERTYPE_AARP:
221 		aarp_print(p, length);
222 		return (1);
223 
224 	case ETHERTYPE_IPX:
225 		printf("(NOV-ETHII) ");
226 		ipx_print(p, length);
227 		return (1);
228 
229 	case ETHERTYPE_8021Q:
230 	        if (eflag)
231 		    printf("vlan %u, p %u%s, ",
232 			   ntohs(*(u_int16_t *)p) & 0xfff,
233 			   ntohs(*(u_int16_t *)p) >> 13,
234 			   (ntohs(*(u_int16_t *)p) & 0x1000) ? ", CFI" : "");
235 
236 		ether_type = ntohs(*(u_int16_t *)(p + 2));
237 		p += 4;
238 		length -= 4;
239 		caplen -= 4;
240 
241 		if (ether_type > ETHERMTU) {
242 		        if (eflag)
243 			        printf("ethertype %s, ",
244 				       tok2str(ethertype_values,"0x%04x", ether_type));
245 			goto recurse;
246 		}
247 
248 		*extracted_ether_type = 0;
249 
250 		if (llc_print(p, length, caplen, p - 18, p - 12,
251 		    extracted_ether_type) == 0) {
252                         ether_hdr_print(p - 18, length + 4);
253 
254                         if (!suppress_default_print) {
255                                 default_print(p - 18, caplen + 4);
256                         }
257 		}
258 
259 
260 		return (1);
261 
262         case ETHERTYPE_JUMBO:
263                 ether_type = ntohs(*(u_int16_t *)(p));
264                 p += 2;
265                 length -= 2;
266                 caplen -= 2;
267 
268                 if (ether_type > ETHERMTU) {
269                     if (eflag)
270                         printf("ethertype %s, ",
271                                tok2str(ethertype_values,"0x%04x", ether_type));
272                     goto recurse;
273                 }
274 
275                 *extracted_ether_type = 0;
276 
277                 if (llc_print(p, length, caplen, p - 16, p - 10,
278                               extracted_ether_type) == 0) {
279                     ether_hdr_print(p - 16, length + 2);
280 
281                     if (!suppress_default_print) {
282                             default_print(p - 16, caplen + 2);
283                     }
284                 }
285 
286                 return (1);
287 
288         case ETHERTYPE_ISO:
289                 isoclns_print(p+1, length-1, length-1);
290                 return(1);
291 
292 	case ETHERTYPE_PPPOED:
293 	case ETHERTYPE_PPPOES:
294 	case ETHERTYPE_PPPOED2:
295 	case ETHERTYPE_PPPOES2:
296 		pppoe_print(p, length);
297 		return (1);
298 
299 	case ETHERTYPE_EAPOL:
300 	        eap_print(gndo, p, length);
301 		return (1);
302 
303 	case ETHERTYPE_RRCP:
304 	        rrcp_print(gndo, p - 14 , length + 14);
305 		return (1);
306 
307 	case ETHERTYPE_PPP:
308 		if (length) {
309 			printf(": ");
310 			ppp_print(p, length);
311 		}
312 		return (1);
313 
314 	case ETHERTYPE_MPCP:
315 	        mpcp_print(p, length);
316 		return (1);
317 
318 	case ETHERTYPE_SLOW:
319 	        slow_print(p, length);
320 		return (1);
321 
322 	case ETHERTYPE_CFM:
323 	case ETHERTYPE_CFM_OLD:
324 	        cfm_print(p, length);
325 		return (1);
326 
327 	case ETHERTYPE_LLDP:
328 	        lldp_print(p, length);
329 		return (1);
330 
331         case ETHERTYPE_LOOPBACK:
332                 return (1);
333 
334 	case ETHERTYPE_MPLS:
335 	case ETHERTYPE_MPLS_MULTI:
336 		mpls_print(p, length);
337 		return (1);
338 
339 	case ETHERTYPE_LAT:
340 	case ETHERTYPE_SCA:
341 	case ETHERTYPE_MOPRC:
342 	case ETHERTYPE_MOPDL:
343 		/* default_print for now */
344 	default:
345 		return (0);
346 	}
347 }
348 
349 
350 /*
351  * Local Variables:
352  * c-style: whitesmith
353  * c-basic-offset: 8
354  * End:
355  */
356 
357