xref: /freebsd/contrib/tcpdump/print-enc.c (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
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 /* \summary: OpenBSD IPsec encapsulation BPF layer printer */
25 
26 #ifdef HAVE_CONFIG_H
27 #include "config.h"
28 #endif
29 
30 #include <netdissect-stdinc.h>
31 
32 #include "netdissect.h"
33 #include "extract.h"
34 
35 /* From $OpenBSD: if_enc.h,v 1.8 2001/06/25 05:14:00 angelos Exp $ */
36 /*
37  * The authors of this code are John Ioannidis (ji@tla.org),
38  * Angelos D. Keromytis (kermit@csd.uch.gr) and
39  * Niels Provos (provos@physnet.uni-hamburg.de).
40  *
41  * This code was written by John Ioannidis for BSD/OS in Athens, Greece,
42  * in November 1995.
43  *
44  * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
45  * by Angelos D. Keromytis.
46  *
47  * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
48  * and Niels Provos.
49  *
50  * Copyright (C) 1995, 1996, 1997, 1998 by John Ioannidis, Angelos D. Keromytis
51  * and Niels Provos.
52  * Copyright (c) 2001, Angelos D. Keromytis.
53  *
54  * Permission to use, copy, and modify this software with or without fee
55  * is hereby granted, provided that this entire notice is included in
56  * all copies of any software which is or includes a copy or
57  * modification of this software.
58  * You may use this code under the GNU public license if you so wish. Please
59  * contribute changes back to the authors under this freer than GPL license
60  * so that we may further the use of strong encryption without limitations to
61  * all.
62  *
63  * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
64  * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
65  * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
66  * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
67  * PURPOSE.
68  */
69 
70 #define ENC_HDRLEN	12
71 
72 /* From $OpenBSD: mbuf.h,v 1.56 2002/01/25 15:50:23 art Exp $	*/
73 #define M_CONF		0x0400  /* packet was encrypted (ESP-transport) */
74 #define M_AUTH		0x0800  /* packet was authenticated (AH) */
75 
76 struct enchdr {
77 	uint32_t af;
78 	uint32_t spi;
79 	uint32_t flags;
80 };
81 
82 #define ENC_PRINT_TYPE(wh, xf, nam) \
83 	if ((wh) & (xf)) { \
84 		ND_PRINT((ndo, "%s%s", nam, (wh) == (xf) ? "): " : ",")); \
85 		(wh) &= ~(xf); \
86 	}
87 
88 u_int
89 enc_if_print(netdissect_options *ndo,
90              const struct pcap_pkthdr *h, register const u_char *p)
91 {
92 	register u_int length = h->len;
93 	register u_int caplen = h->caplen;
94 	int flags;
95 	const struct enchdr *hdr;
96 
97 	if (caplen < ENC_HDRLEN) {
98 		ND_PRINT((ndo, "[|enc]"));
99 		goto out;
100 	}
101 
102 	hdr = (const struct enchdr *)p;
103 	flags = hdr->flags;
104 	if (flags == 0)
105 		ND_PRINT((ndo, "(unprotected): "));
106 	else
107 		ND_PRINT((ndo, "("));
108 	ENC_PRINT_TYPE(flags, M_AUTH, "authentic");
109 	ENC_PRINT_TYPE(flags, M_CONF, "confidential");
110 	/* ENC_PRINT_TYPE(flags, M_TUNNEL, "tunnel"); */
111 	ND_PRINT((ndo, "SPI 0x%08x: ", EXTRACT_32BITS(&hdr->spi)));
112 
113 	length -= ENC_HDRLEN;
114 	caplen -= ENC_HDRLEN;
115 	p += ENC_HDRLEN;
116 
117 	switch (hdr->af) {
118 	case AF_INET:
119 		ip_print(ndo, p, length);
120 		break;
121 #ifdef AF_INET6
122 	case AF_INET6:
123 		ip6_print(ndo, p, length);
124 		break;
125 #endif
126 	}
127 
128 out:
129 	return (ENC_HDRLEN);
130 }
131 
132 
133 /*
134  * Local Variables:
135  * c-style: whitesmith
136  * c-basic-offset: 8
137  * End:
138  */
139