contrib/tcpdump/print-enc.c

   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  */