xref: /netbsd-src/external/bsd/tcpdump/dist/print-enc.c (revision 627f7eb200a4419d89b531d55fccd2ee3ffdcde0)
1 /*	$OpenBSD: print-enc.c,v 1.7 2002/02/19 19:39:40 millert Exp $	*/
2 
3 /*
4  * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that: (1) source code distributions
9  * retain the above copyright notice and this paragraph in its entirety, (2)
10  * distributions including binary code include the above copyright notice and
11  * this paragraph in its entirety in the documentation or other materials
12  * provided with the distribution, and (3) all advertising materials mentioning
13  * features or use of this software display the following acknowledgement:
14  * ``This product includes software developed by the University of California,
15  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
16  * the University nor the names of its contributors may be used to endorse
17  * or promote products derived from this software without specific prior
18  * written permission.
19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
20  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
22  */
23 
24 #include <sys/cdefs.h>
25 #ifndef lint
26 __RCSID("$NetBSD: print-enc.c,v 1.7 2017/02/05 04:05:05 spz Exp $");
27 #endif
28 
29 /* \summary: OpenBSD IPsec encapsulation BPF layer printer */
30 
31 #ifdef HAVE_CONFIG_H
32 #include "config.h"
33 #endif
34 
35 #include <netdissect-stdinc.h>
36 
37 #include "netdissect.h"
38 #include "extract.h"
39 
40 /* From $OpenBSD: if_enc.h,v 1.8 2001/06/25 05:14:00 angelos Exp $ */
41 /*
42  * The authors of this code are John Ioannidis (ji@tla.org),
43  * Angelos D. Keromytis (kermit@csd.uch.gr) and
44  * Niels Provos (provos@physnet.uni-hamburg.de).
45  *
46  * This code was written by John Ioannidis for BSD/OS in Athens, Greece,
47  * in November 1995.
48  *
49  * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
50  * by Angelos D. Keromytis.
51  *
52  * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
53  * and Niels Provos.
54  *
55  * Copyright (C) 1995, 1996, 1997, 1998 by John Ioannidis, Angelos D. Keromytis
56  * and Niels Provos.
57  * Copyright (c) 2001, Angelos D. Keromytis.
58  *
59  * Permission to use, copy, and modify this software with or without fee
60  * is hereby granted, provided that this entire notice is included in
61  * all copies of any software which is or includes a copy or
62  * modification of this software.
63  * You may use this code under the GNU public license if you so wish. Please
64  * contribute changes back to the authors under this freer than GPL license
65  * so that we may further the use of strong encryption without limitations to
66  * all.
67  *
68  * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
69  * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
70  * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
71  * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
72  * PURPOSE.
73  */
74 
75 #define ENC_HDRLEN	12
76 
77 /* From $OpenBSD: mbuf.h,v 1.56 2002/01/25 15:50:23 art Exp $	*/
78 #define M_CONF		0x0400  /* packet was encrypted (ESP-transport) */
79 #define M_AUTH		0x0800  /* packet was authenticated (AH) */
80 
81 struct enchdr {
82 	uint32_t af;
83 	uint32_t spi;
84 	uint32_t flags;
85 };
86 
87 #define ENC_PRINT_TYPE(wh, xf, nam) \
88 	if ((wh) & (xf)) { \
89 		ND_PRINT((ndo, "%s%s", nam, (wh) == (xf) ? "): " : ",")); \
90 		(wh) &= ~(xf); \
91 	}
92 
93 u_int
94 enc_if_print(netdissect_options *ndo,
95              const struct pcap_pkthdr *h, register const u_char *p)
96 {
97 	register u_int length = h->len;
98 	register u_int caplen = h->caplen;
99 	int flags;
100 	const struct enchdr *hdr;
101 
102 	if (caplen < ENC_HDRLEN) {
103 		ND_PRINT((ndo, "[|enc]"));
104 		goto out;
105 	}
106 
107 	hdr = (const struct enchdr *)p;
108 	flags = hdr->flags;
109 	if (flags == 0)
110 		ND_PRINT((ndo, "(unprotected): "));
111 	else
112 		ND_PRINT((ndo, "("));
113 	ENC_PRINT_TYPE(flags, M_AUTH, "authentic");
114 	ENC_PRINT_TYPE(flags, M_CONF, "confidential");
115 	/* ENC_PRINT_TYPE(flags, M_TUNNEL, "tunnel"); */
116 	ND_PRINT((ndo, "SPI 0x%08x: ", EXTRACT_32BITS(&hdr->spi)));
117 
118 	length -= ENC_HDRLEN;
119 	caplen -= ENC_HDRLEN;
120 	p += ENC_HDRLEN;
121 
122 	switch (hdr->af) {
123 	case AF_INET:
124 		ip_print(ndo, p, length);
125 		break;
126 #ifdef AF_INET6
127 	case AF_INET6:
128 		ip6_print(ndo, p, length);
129 		break;
130 #endif
131 	}
132 
133 out:
134 	return (ENC_HDRLEN);
135 }
136 
137 
138 /*
139  * Local Variables:
140  * c-style: whitesmith
141  * c-basic-offset: 8
142  * End:
143  */
144