xref: /freebsd/contrib/tcpdump/print-ether.c (revision 30d239bc4c510432e65a84fa1c14ed67a3ab1c92)
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 1.95.2.6 2006/02/20 18:15:03 hannes 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_SLOW,           "Slow Protocols" },
71     { ETHERTYPE_PPPOED,         "PPPoE D" },
72     { ETHERTYPE_PPPOES,         "PPPoE S" },
73     { ETHERTYPE_EAPOL,          "EAPOL" },
74     { ETHERTYPE_JUMBO,          "Jumbo" },
75     { ETHERTYPE_LOOPBACK,       "Loopback" },
76     { ETHERTYPE_ISO,            "OSI" },
77     { ETHERTYPE_GRE_ISO,        "GRE-OSI" },
78     { 0, NULL}
79 };
80 
81 static inline void
82 ether_hdr_print(register const u_char *bp, u_int length)
83 {
84 	register const struct ether_header *ep;
85 	ep = (const struct ether_header *)bp;
86 
87 	(void)printf("%s > %s",
88 		     etheraddr_string(ESRC(ep)),
89 		     etheraddr_string(EDST(ep)));
90 
91 	if (!qflag) {
92 	        if (ntohs(ep->ether_type) <= ETHERMTU)
93 		          (void)printf(", 802.3");
94                 else
95 		          (void)printf(", ethertype %s (0x%04x)",
96 				       tok2str(ethertype_values,"Unknown", ntohs(ep->ether_type)),
97                                        ntohs(ep->ether_type));
98         } else {
99                 if (ntohs(ep->ether_type) <= ETHERMTU)
100                           (void)printf(", 802.3");
101                 else
102                           (void)printf(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", ntohs(ep->ether_type)));
103         }
104 
105 	(void)printf(", length %u: ", length);
106 }
107 
108 void
109 ether_print(const u_char *p, u_int length, u_int caplen)
110 {
111 	struct ether_header *ep;
112 	u_short ether_type;
113 	u_short extracted_ether_type;
114 
115 	if (caplen < ETHER_HDRLEN) {
116 		printf("[|ether]");
117 		return;
118 	}
119 
120 	if (eflag)
121 		ether_hdr_print(p, length);
122 
123 	length -= ETHER_HDRLEN;
124 	caplen -= ETHER_HDRLEN;
125 	ep = (struct ether_header *)p;
126 	p += ETHER_HDRLEN;
127 
128 	ether_type = ntohs(ep->ether_type);
129 
130 	/*
131 	 * Is it (gag) an 802.3 encapsulation?
132 	 */
133 	if (ether_type <= ETHERMTU) {
134 		/* Try to print the LLC-layer header & higher layers */
135 		if (llc_print(p, length, caplen, ESRC(ep), EDST(ep),
136 		    &extracted_ether_type) == 0) {
137 			/* ether_type not known, print raw packet */
138 			if (!eflag)
139 				ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
140 
141 			if (!suppress_default_print)
142 				default_print(p, caplen);
143 		}
144 	} else if (ether_encap_print(ether_type, p, length, caplen,
145 	    &extracted_ether_type) == 0) {
146 		/* ether_type not known, print raw packet */
147 		if (!eflag)
148 			ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
149 
150 		if (!suppress_default_print)
151 			default_print(p, caplen);
152 	}
153 }
154 
155 /*
156  * This is the top level routine of the printer.  'p' points
157  * to the ether header of the packet, 'h->ts' is the timestamp,
158  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
159  * is the number of bytes actually captured.
160  */
161 u_int
162 ether_if_print(const struct pcap_pkthdr *h, const u_char *p)
163 {
164 	ether_print(p, h->len, h->caplen);
165 
166 	return (ETHER_HDRLEN);
167 }
168 
169 /*
170  * Prints the packet encapsulated in an Ethernet data segment
171  * (or an equivalent encapsulation), given the Ethernet type code.
172  *
173  * Returns non-zero if it can do so, zero if the ethertype is unknown.
174  *
175  * The Ethernet type code is passed through a pointer; if it was
176  * ETHERTYPE_8021Q, it gets updated to be the Ethernet type of
177  * the 802.1Q payload, for the benefit of lower layers that might
178  * want to know what it is.
179  */
180 
181 int
182 ether_encap_print(u_short ether_type, const u_char *p,
183     u_int length, u_int caplen, u_short *extracted_ether_type)
184 {
185  recurse:
186 	*extracted_ether_type = ether_type;
187 
188 	switch (ether_type) {
189 
190 	case ETHERTYPE_IP:
191 	        ip_print(gndo, p, length);
192 		return (1);
193 
194 #ifdef INET6
195 	case ETHERTYPE_IPV6:
196 		ip6_print(p, length);
197 		return (1);
198 #endif /*INET6*/
199 
200 	case ETHERTYPE_ARP:
201 	case ETHERTYPE_REVARP:
202   	        arp_print(gndo, p, length, caplen);
203 		return (1);
204 
205 	case ETHERTYPE_DN:
206 		decnet_print(p, length, caplen);
207 		return (1);
208 
209 	case ETHERTYPE_ATALK:
210 		if (vflag)
211 			fputs("et1 ", stdout);
212 		atalk_print(p, length);
213 		return (1);
214 
215 	case ETHERTYPE_AARP:
216 		aarp_print(p, length);
217 		return (1);
218 
219 	case ETHERTYPE_IPX:
220 		printf("(NOV-ETHII) ");
221 		ipx_print(p, length);
222 		return (1);
223 
224 	case ETHERTYPE_8021Q:
225 	        if (eflag)
226 		    printf("vlan %u, p %u%s, ",
227 			   ntohs(*(u_int16_t *)p) & 0xfff,
228 			   ntohs(*(u_int16_t *)p) >> 13,
229 			   (ntohs(*(u_int16_t *)p) & 0x1000) ? ", CFI" : "");
230 
231 		ether_type = ntohs(*(u_int16_t *)(p + 2));
232 		p += 4;
233 		length -= 4;
234 		caplen -= 4;
235 
236 		if (ether_type > ETHERMTU) {
237 		        if (eflag)
238 			        printf("ethertype %s, ",
239 				       tok2str(ethertype_values,"0x%04x", ether_type));
240 			goto recurse;
241 		}
242 
243 		*extracted_ether_type = 0;
244 
245 		if (llc_print(p, length, caplen, p - 18, p - 12,
246 		    extracted_ether_type) == 0) {
247                         ether_hdr_print(p - 18, length + 4);
248 
249                         if (!suppress_default_print) {
250                                 default_print(p - 18, caplen + 4);
251                         }
252 		}
253 
254 
255 		return (1);
256 
257         case ETHERTYPE_JUMBO:
258                 ether_type = ntohs(*(u_int16_t *)(p));
259                 p += 2;
260                 length -= 2;
261                 caplen -= 2;
262 
263                 if (ether_type > ETHERMTU) {
264                     if (eflag)
265                         printf("ethertype %s, ",
266                                tok2str(ethertype_values,"0x%04x", ether_type));
267                     goto recurse;
268                 }
269 
270                 *extracted_ether_type = 0;
271 
272                 if (llc_print(p, length, caplen, p - 16, p - 10,
273                               extracted_ether_type) == 0) {
274                     ether_hdr_print(p - 16, length + 2);
275 
276                     if (!suppress_default_print) {
277                             default_print(p - 16, caplen + 2);
278                     }
279                 }
280 
281                 return (1);
282 
283         case ETHERTYPE_ISO:
284                 isoclns_print(p+1, length-1, length-1);
285                 return(1);
286 
287 	case ETHERTYPE_PPPOED:
288 	case ETHERTYPE_PPPOES:
289 	case ETHERTYPE_PPPOED2:
290 	case ETHERTYPE_PPPOES2:
291 		pppoe_print(p, length);
292 		return (1);
293 
294 	case ETHERTYPE_EAPOL:
295 	        eap_print(gndo, p, length);
296 		return (1);
297 
298 	case ETHERTYPE_PPP:
299 		if (length) {
300 			printf(": ");
301 			ppp_print(p, length);
302 		}
303 		return (1);
304 
305 	case ETHERTYPE_SLOW:
306 	        slow_print(p, length);
307 		return (1);
308 
309         case ETHERTYPE_LOOPBACK:
310                 return (1);
311 
312 	case ETHERTYPE_MPLS:
313 	case ETHERTYPE_MPLS_MULTI:
314 		mpls_print(p, length);
315 		return (1);
316 
317 	case ETHERTYPE_LAT:
318 	case ETHERTYPE_SCA:
319 	case ETHERTYPE_MOPRC:
320 	case ETHERTYPE_MOPDL:
321 		/* default_print for now */
322 	default:
323 		return (0);
324 	}
325 }
326 
327 
328 /*
329  * Local Variables:
330  * c-style: whitesmith
331  * c-basic-offset: 8
332  * End:
333  */
334 
335