xref: /freebsd/contrib/tcpdump/print-ether.c (revision 2ebc47db5b33ca26b73b76374760c587c38ef385)
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 #ifndef lint
22 static const char rcsid[] _U_ =
23     "@(#) $Header: /tcpdump/master/tcpdump/print-ether.c,v 1.95.2.4 2005/07/10 14:47:57 hannes Exp $ (LBL)";
24 #endif
25 
26 #ifdef HAVE_CONFIG_H
27 #include "config.h"
28 #endif
29 
30 #include <tcpdump-stdinc.h>
31 
32 #include <stdio.h>
33 #include <pcap.h>
34 
35 #include "interface.h"
36 #include "addrtoname.h"
37 #include "ethertype.h"
38 
39 #include "ether.h"
40 
41 const struct tok ethertype_values[] = {
42     { ETHERTYPE_IP,		"IPv4" },
43     { ETHERTYPE_MPLS,		"MPLS unicast" },
44     { ETHERTYPE_MPLS_MULTI,	"MPLS multicast" },
45     { ETHERTYPE_IPV6,		"IPv6" },
46     { ETHERTYPE_8021Q,		"802.1Q" },
47     { ETHERTYPE_VMAN,		"VMAN" },
48     { ETHERTYPE_PUP,            "PUP" },
49     { ETHERTYPE_ARP,            "ARP"},
50     { ETHERTYPE_REVARP ,        "Reverse ARP"},
51     { ETHERTYPE_NS,             "NS" },
52     { ETHERTYPE_SPRITE,         "Sprite" },
53     { ETHERTYPE_TRAIL,          "Trail" },
54     { ETHERTYPE_MOPDL,          "MOP DL" },
55     { ETHERTYPE_MOPRC,          "MOP RC" },
56     { ETHERTYPE_DN,             "DN" },
57     { ETHERTYPE_LAT,            "LAT" },
58     { ETHERTYPE_SCA,            "SCA" },
59     { ETHERTYPE_LANBRIDGE,      "Lanbridge" },
60     { ETHERTYPE_DECDNS,         "DEC DNS" },
61     { ETHERTYPE_DECDTS,         "DEC DTS" },
62     { ETHERTYPE_VEXP,           "VEXP" },
63     { ETHERTYPE_VPROD,          "VPROD" },
64     { ETHERTYPE_ATALK,          "Appletalk" },
65     { ETHERTYPE_AARP,           "Appletalk ARP" },
66     { ETHERTYPE_IPX,            "IPX" },
67     { ETHERTYPE_PPP,            "PPP" },
68     { ETHERTYPE_SLOW,           "Slow Protocols" },
69     { ETHERTYPE_PPPOED,         "PPPoE D" },
70     { ETHERTYPE_PPPOES,         "PPPoE S" },
71     { ETHERTYPE_EAPOL,          "EAPOL" },
72     { ETHERTYPE_JUMBO,          "Jumbo" },
73     { ETHERTYPE_LOOPBACK,       "Loopback" },
74     { ETHERTYPE_ISO,            "OSI" },
75     { ETHERTYPE_GRE_ISO,        "GRE-OSI" },
76     { 0, NULL}
77 };
78 
79 static inline void
80 ether_hdr_print(register const u_char *bp, u_int length)
81 {
82 	register const struct ether_header *ep;
83 	ep = (const struct ether_header *)bp;
84 
85 	(void)printf("%s > %s",
86 		     etheraddr_string(ESRC(ep)),
87 		     etheraddr_string(EDST(ep)));
88 
89 	if (!qflag) {
90 	        if (ntohs(ep->ether_type) <= ETHERMTU)
91 		          (void)printf(", 802.3");
92                 else
93 		          (void)printf(", ethertype %s (0x%04x)",
94 				       tok2str(ethertype_values,"Unknown", ntohs(ep->ether_type)),
95                                        ntohs(ep->ether_type));
96         } else {
97                 if (ntohs(ep->ether_type) <= ETHERMTU)
98                           (void)printf(", 802.3");
99                 else
100                           (void)printf(", %s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", ntohs(ep->ether_type)));
101         }
102 
103 	(void)printf(", length %u: ", length);
104 }
105 
106 void
107 ether_print(const u_char *p, u_int length, u_int caplen)
108 {
109 	struct ether_header *ep;
110 	u_short ether_type;
111 	u_short extracted_ether_type;
112 
113 	if (caplen < ETHER_HDRLEN) {
114 		printf("[|ether]");
115 		return;
116 	}
117 
118 	if (eflag)
119 		ether_hdr_print(p, length);
120 
121 	length -= ETHER_HDRLEN;
122 	caplen -= ETHER_HDRLEN;
123 	ep = (struct ether_header *)p;
124 	p += ETHER_HDRLEN;
125 
126 	ether_type = ntohs(ep->ether_type);
127 
128 	/*
129 	 * Is it (gag) an 802.3 encapsulation?
130 	 */
131 	extracted_ether_type = 0;
132 	if (ether_type <= ETHERMTU) {
133 		/* Try to print the LLC-layer header & higher layers */
134 		if (llc_print(p, length, caplen, ESRC(ep), EDST(ep),
135 		    &extracted_ether_type) == 0) {
136 			/* ether_type not known, print raw packet */
137 			if (!eflag)
138 				ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
139 
140 			if (!suppress_default_print)
141 				default_print(p, caplen);
142 		}
143 	} else if (ether_encap_print(ether_type, p, length, caplen,
144 	    &extracted_ether_type) == 0) {
145 		/* ether_type not known, print raw packet */
146 		if (!eflag)
147 			ether_hdr_print((u_char *)ep, length + ETHER_HDRLEN);
148 
149 		if (!suppress_default_print)
150 			default_print(p, caplen);
151 	}
152 }
153 
154 /*
155  * This is the top level routine of the printer.  'p' points
156  * to the ether header of the packet, 'h->ts' is the timestamp,
157  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
158  * is the number of bytes actually captured.
159  */
160 u_int
161 ether_if_print(const struct pcap_pkthdr *h, const u_char *p)
162 {
163 	ether_print(p, h->len, h->caplen);
164 
165 	return (ETHER_HDRLEN);
166 }
167 
168 /*
169  * Prints the packet encapsulated in an Ethernet data segment
170  * (or an equivalent encapsulation), given the Ethernet type code.
171  *
172  * Returns non-zero if it can do so, zero if the ethertype is unknown.
173  *
174  * The Ethernet type code is passed through a pointer; if it was
175  * ETHERTYPE_8021Q, it gets updated to be the Ethernet type of
176  * the 802.1Q payload, for the benefit of lower layers that might
177  * want to know what it is.
178  */
179 
180 int
181 ether_encap_print(u_short ether_type, const u_char *p,
182     u_int length, u_int caplen, u_short *extracted_ether_type)
183 {
184  recurse:
185 	*extracted_ether_type = ether_type;
186 
187 	switch (ether_type) {
188 
189 	case ETHERTYPE_IP:
190 	        ip_print(gndo, p, length);
191 		return (1);
192 
193 #ifdef INET6
194 	case ETHERTYPE_IPV6:
195 		ip6_print(p, length);
196 		return (1);
197 #endif /*INET6*/
198 
199 	case ETHERTYPE_ARP:
200 	case ETHERTYPE_REVARP:
201   	        arp_print(gndo, p, length, caplen);
202 		return (1);
203 
204 	case ETHERTYPE_DN:
205 		decnet_print(p, length, caplen);
206 		return (1);
207 
208 	case ETHERTYPE_ATALK:
209 		if (vflag)
210 			fputs("et1 ", stdout);
211 		atalk_print(p, length);
212 		return (1);
213 
214 	case ETHERTYPE_AARP:
215 		aarp_print(p, length);
216 		return (1);
217 
218 	case ETHERTYPE_IPX:
219 		printf("(NOV-ETHII) ");
220 		ipx_print(p, length);
221 		return (1);
222 
223 	case ETHERTYPE_8021Q:
224 	        if (eflag)
225 		    printf("vlan %u, p %u%s, ",
226 			   ntohs(*(u_int16_t *)p) & 0xfff,
227 			   ntohs(*(u_int16_t *)p) >> 13,
228 			   (ntohs(*(u_int16_t *)p) & 0x1000) ? ", CFI" : "");
229 
230 		ether_type = ntohs(*(u_int16_t *)(p + 2));
231 		p += 4;
232 		length -= 4;
233 		caplen -= 4;
234 
235 		if (ether_type > ETHERMTU) {
236 		        if (eflag)
237 			        printf("ethertype %s, ",
238 				       tok2str(ethertype_values,"0x%04x", ether_type));
239 			goto recurse;
240 		}
241 
242 		*extracted_ether_type = 0;
243 
244 		if (llc_print(p, length, caplen, p - 18, p - 12,
245 		    extracted_ether_type) == 0) {
246 				ether_hdr_print(p - 18, length + 4);
247 		}
248 
249 		if (!suppress_default_print)
250 		        default_print(p - 18, caplen + 4);
251 
252 		return (1);
253 
254         case ETHERTYPE_JUMBO:
255                 ether_type = ntohs(*(u_int16_t *)(p));
256                 p += 2;
257                 length -= 2;
258                 caplen -= 2;
259 
260                 if (ether_type > ETHERMTU) {
261                     if (eflag)
262                         printf("ethertype %s, ",
263                                tok2str(ethertype_values,"0x%04x", ether_type));
264                     goto recurse;
265                 }
266 
267                 *extracted_ether_type = 0;
268 
269                 if (llc_print(p, length, caplen, p - 16, p - 10,
270                               extracted_ether_type) == 0) {
271                     ether_hdr_print(p - 16, length + 2);
272                 }
273 
274                 if (!suppress_default_print)
275                     default_print(p - 16, caplen + 2);
276 
277                 return (1);
278 
279         case ETHERTYPE_ISO:
280                 isoclns_print(p+1, length-1, length-1);
281                 return(1);
282 
283 	case ETHERTYPE_PPPOED:
284 	case ETHERTYPE_PPPOES:
285 		pppoe_print(p, length);
286 		return (1);
287 
288 	case ETHERTYPE_EAPOL:
289 	        eap_print(gndo, p, length);
290 		return (1);
291 
292 	case ETHERTYPE_PPP:
293 		if (length) {
294 			printf(": ");
295 			ppp_print(p, length);
296 		}
297 		return (1);
298 
299 	case ETHERTYPE_SLOW:
300 	        slow_print(p, length);
301 		return (1);
302 
303         case ETHERTYPE_LOOPBACK:
304                 return (1);
305 
306 	case ETHERTYPE_MPLS:
307 	case ETHERTYPE_MPLS_MULTI:
308 		mpls_print(p, length);
309 		return (1);
310 
311 	case ETHERTYPE_LAT:
312 	case ETHERTYPE_SCA:
313 	case ETHERTYPE_MOPRC:
314 	case ETHERTYPE_MOPDL:
315 		/* default_print for now */
316 	default:
317 		return (0);
318 	}
319 }
320 
321 
322 /*
323  * Local Variables:
324  * c-style: whitesmith
325  * c-basic-offset: 8
326  * End:
327  */
328 
329