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      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 (at) tla.org),
     38  * Angelos D. Keromytis (kermit (at) csd.uch.gr) and
     39  * Niels Provos (provos (at) 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