xref: /freebsd/contrib/tcpdump/print-ether.c (revision 282a3889ebf826db9839be296ff1dd903f6d6d6e)
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 1.95.2.4 2005/07/10 14:47:57 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 	extracted_ether_type = 0;
134 	if (ether_type <= ETHERMTU) {
135 		/* Try to print the LLC-layer header & higher layers */
136 		if (llc_print(p, length, caplen, ESRC(ep), EDST(ep),
137 		    &extracted_ether_type) == 0) {
138 			/* ether_type not known, print raw packet */
139 			if (!eflag)
140 				ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
141 
142 			if (!suppress_default_print)
143 				default_print(p, caplen);
144 		}
145 	} else if (ether_encap_print(ether_type, p, length, caplen,
146 	    &extracted_ether_type) == 0) {
147 		/* ether_type not known, print raw packet */
148 		if (!eflag)
149 			ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
150 
151 		if (!suppress_default_print)
152 			default_print(p, caplen);
153 	}
154 }
155 
156 /*
157  * This is the top level routine of the printer.  'p' points
158  * to the ether header of the packet, 'h->ts' is the timestamp,
159  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
160  * is the number of bytes actually captured.
161  */
162 u_int
163 ether_if_print(const struct pcap_pkthdr *h, const u_char *p)
164 {
165 	ether_print(p, h->len, h->caplen);
166 
167 	return (ETHER_HDRLEN);
168 }
169 
170 /*
171  * Prints the packet encapsulated in an Ethernet data segment
172  * (or an equivalent encapsulation), given the Ethernet type code.
173  *
174  * Returns non-zero if it can do so, zero if the ethertype is unknown.
175  *
176  * The Ethernet type code is passed through a pointer; if it was
177  * ETHERTYPE_8021Q, it gets updated to be the Ethernet type of
178  * the 802.1Q payload, for the benefit of lower layers that might
179  * want to know what it is.
180  */
181 
182 int
183 ether_encap_print(u_short ether_type, const u_char *p,
184     u_int length, u_int caplen, u_short *extracted_ether_type)
185 {
186  recurse:
187 	*extracted_ether_type = ether_type;
188 
189 	switch (ether_type) {
190 
191 	case ETHERTYPE_IP:
192 	        ip_print(gndo, p, length);
193 		return (1);
194 
195 #ifdef INET6
196 	case ETHERTYPE_IPV6:
197 		ip6_print(p, length);
198 		return (1);
199 #endif /*INET6*/
200 
201 	case ETHERTYPE_ARP:
202 	case ETHERTYPE_REVARP:
203   	        arp_print(gndo, p, length, caplen);
204 		return (1);
205 
206 	case ETHERTYPE_DN:
207 		decnet_print(p, length, caplen);
208 		return (1);
209 
210 	case ETHERTYPE_ATALK:
211 		if (vflag)
212 			fputs("et1 ", stdout);
213 		atalk_print(p, length);
214 		return (1);
215 
216 	case ETHERTYPE_AARP:
217 		aarp_print(p, length);
218 		return (1);
219 
220 	case ETHERTYPE_IPX:
221 		printf("(NOV-ETHII) ");
222 		ipx_print(p, length);
223 		return (1);
224 
225 	case ETHERTYPE_8021Q:
226 	        if (eflag)
227 		    printf("vlan %u, p %u%s, ",
228 			   ntohs(*(u_int16_t *)p) & 0xfff,
229 			   ntohs(*(u_int16_t *)p) >> 13,
230 			   (ntohs(*(u_int16_t *)p) & 0x1000) ? ", CFI" : "");
231 
232 		ether_type = ntohs(*(u_int16_t *)(p + 2));
233 		p += 4;
234 		length -= 4;
235 		caplen -= 4;
236 
237 		if (ether_type > ETHERMTU) {
238 		        if (eflag)
239 			        printf("ethertype %s, ",
240 				       tok2str(ethertype_values,"0x%04x", ether_type));
241 			goto recurse;
242 		}
243 
244 		*extracted_ether_type = 0;
245 
246 		if (llc_print(p, length, caplen, p - 18, p - 12,
247 		    extracted_ether_type) == 0) {
248 				ether_hdr_print(p - 18, length + 4);
249 		}
250 
251 		if (!suppress_default_print)
252 		        default_print(p - 18, caplen + 4);
253 
254 		return (1);
255 
256         case ETHERTYPE_JUMBO:
257                 ether_type = ntohs(*(u_int16_t *)(p));
258                 p += 2;
259                 length -= 2;
260                 caplen -= 2;
261 
262                 if (ether_type > ETHERMTU) {
263                     if (eflag)
264                         printf("ethertype %s, ",
265                                tok2str(ethertype_values,"0x%04x", ether_type));
266                     goto recurse;
267                 }
268 
269                 *extracted_ether_type = 0;
270 
271                 if (llc_print(p, length, caplen, p - 16, p - 10,
272                               extracted_ether_type) == 0) {
273                     ether_hdr_print(p - 16, length + 2);
274                 }
275 
276                 if (!suppress_default_print)
277                     default_print(p - 16, caplen + 2);
278 
279                 return (1);
280 
281         case ETHERTYPE_ISO:
282                 isoclns_print(p+1, length-1, length-1);
283                 return(1);
284 
285 	case ETHERTYPE_PPPOED:
286 	case ETHERTYPE_PPPOES:
287 	case ETHERTYPE_PPPOED2:
288 	case ETHERTYPE_PPPOES2:
289 		pppoe_print(p, length);
290 		return (1);
291 
292 	case ETHERTYPE_EAPOL:
293 	        eap_print(gndo, p, length);
294 		return (1);
295 
296 	case ETHERTYPE_PPP:
297 		if (length) {
298 			printf(": ");
299 			ppp_print(p, length);
300 		}
301 		return (1);
302 
303 	case ETHERTYPE_SLOW:
304 	        slow_print(p, length);
305 		return (1);
306 
307         case ETHERTYPE_LOOPBACK:
308                 return (1);
309 
310 	case ETHERTYPE_MPLS:
311 	case ETHERTYPE_MPLS_MULTI:
312 		mpls_print(p, length);
313 		return (1);
314 
315 	case ETHERTYPE_LAT:
316 	case ETHERTYPE_SCA:
317 	case ETHERTYPE_MOPRC:
318 	case ETHERTYPE_MOPDL:
319 		/* default_print for now */
320 	default:
321 		return (0);
322 	}
323 }
324 
325 
326 /*
327  * Local Variables:
328  * c-style: whitesmith
329  * c-basic-offset: 8
330  * End:
331  */
332 
333