xref: /freebsd/contrib/tcpdump/print-symantec.c (revision 0b3105a37d7adcadcb720112fed4dc4e8040be99)
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 
22 #define NETDISSECT_REWORKED
23 #ifdef HAVE_CONFIG_H
24 #include "config.h"
25 #endif
26 
27 #include <tcpdump-stdinc.h>
28 
29 #include "interface.h"
30 #include "extract.h"
31 #include "ethertype.h"
32 
33 #include "ether.h"
34 
35 struct symantec_header {
36 	uint8_t  stuff1[6];
37 	uint16_t ether_type;
38 	uint8_t  stuff2[36];
39 };
40 
41 static inline void
42 symantec_hdr_print(netdissect_options *ndo, register const u_char *bp, u_int length)
43 {
44 	register const struct symantec_header *sp;
45 	uint16_t etype;
46 
47 	sp = (const struct symantec_header *)bp;
48 
49 	etype = EXTRACT_16BITS(&sp->ether_type);
50 	if (!ndo->ndo_qflag) {
51 	        if (etype <= ETHERMTU)
52 		          ND_PRINT((ndo, "invalid ethertype %u", etype));
53                 else
54 		          ND_PRINT((ndo, "ethertype %s (0x%04x)",
55 				       tok2str(ethertype_values,"Unknown", etype),
56                                        etype));
57         } else {
58                 if (etype <= ETHERMTU)
59                           ND_PRINT((ndo, "invalid ethertype %u", etype));
60                 else
61                           ND_PRINT((ndo, "%s", tok2str(ethertype_values,"Unknown Ethertype (0x%04x)", etype)));
62         }
63 
64 	ND_PRINT((ndo, ", length %u: ", length));
65 }
66 
67 /*
68  * This is the top level routine of the printer.  'p' points
69  * to the ether header of the packet, 'h->ts' is the timestamp,
70  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
71  * is the number of bytes actually captured.
72  */
73 u_int
74 symantec_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
75 {
76 	u_int length = h->len;
77 	u_int caplen = h->caplen;
78 	struct symantec_header *sp;
79 	u_short ether_type;
80 
81 	if (caplen < sizeof (struct symantec_header)) {
82 		ND_PRINT((ndo, "[|symantec]"));
83 		return caplen;
84 	}
85 
86 	if (ndo->ndo_eflag)
87 		symantec_hdr_print(ndo, p, length);
88 
89 	length -= sizeof (struct symantec_header);
90 	caplen -= sizeof (struct symantec_header);
91 	sp = (struct symantec_header *)p;
92 	p += sizeof (struct symantec_header);
93 
94 	ether_type = EXTRACT_16BITS(&sp->ether_type);
95 
96 	if (ether_type <= ETHERMTU) {
97 		/* ether_type not known, print raw packet */
98 		if (!ndo->ndo_eflag)
99 			symantec_hdr_print(ndo, (u_char *)sp, length + sizeof (struct symantec_header));
100 
101 		if (!ndo->ndo_suppress_default_print)
102 			ND_DEFAULTPRINT(p, caplen);
103 	} else if (ethertype_print(ndo, ether_type, p, length, caplen) == 0) {
104 		/* ether_type not known, print raw packet */
105 		if (!ndo->ndo_eflag)
106 			symantec_hdr_print(ndo, (u_char *)sp, length + sizeof (struct symantec_header));
107 
108 		if (!ndo->ndo_suppress_default_print)
109 			ND_DEFAULTPRINT(p, caplen);
110 	}
111 
112 	return (sizeof (struct symantec_header));
113 }
114