external/bsd/tcpdump/dist/print-pktap.c

   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 #include <sys/cdefs.h>
  23 #ifndef lint
  24 __RCSID("$NetBSD: print-pktap.c,v 1.2 2014/11/20 03:05:03 christos Exp $");
  25 #endif
  26
  27 #define NETDISSECT_REWORKED
  28 #ifdef HAVE_CONFIG_H
  29 #include "config.h"
  30 #endif
  31
  32 #include <tcpdump-stdinc.h>
  33
  34 #include "interface.h"
  35 #include "extract.h"
  36
  37 #ifdef DLT_PKTAP
  38
  39 /*
  40  * XXX - these are little-endian in the captures I've seen, but Apple
  41  * no longer make any big-endian machines (Macs use x86, iOS machines
  42  * use ARM and run it little-endian), so that might be by definition
  43  * or they might be host-endian.
  44  *
  45  * If a big-endian PKTAP file ever shows up, and it comes from a
  46  * big-endian machine, presumably these are host-endian, and we need
  47  * to just fetch the fields directly in tcpdump but byte-swap them
  48  * to host byte order in libpcap.
  49  */
  50 typedef struct pktap_header {
  51         uint32_t        pkt_len;        /* length of pktap header */
  52         uint32_t        pkt_rectype;    /* type of record */
  53         uint32_t        pkt_dlt;        /* DLT type of this packet */
  54         char            pkt_ifname[24]; /* interface name */
  55         uint32_t        pkt_flags;
  56         uint32_t        pkt_pfamily;    /* "protocol family" */
  57         uint32_t        pkt_llhdrlen;   /* link-layer header length? */
  58         uint32_t        pkt_lltrlrlen;  /* link-layer trailer length? */
  59         uint32_t        pkt_pid;        /* process ID */
  60         char            pkt_cmdname[20]; /* command name */
  61         uint32_t        pkt_svc_class;  /* "service class" */
  62         uint16_t        pkt_iftype;     /* "interface type" */
  63         uint16_t        pkt_ifunit;     /* unit number of interface? */
  64         uint32_t        pkt_epid;       /* "effective process ID" */
  65         char            pkt_ecmdname[20]; /* "effective command name" */
  66 } pktap_header_t;
  67
  68 /*
  69  * Record types.
  70  */
  71 #define PKT_REC_NONE    0       /* nothing follows the header */
  72 #define PKT_REC_PACKET  1       /* a packet follows the header */
  73
  74 static inline void
  75 pktap_header_print(netdissect_options *ndo, const u_char *bp, u_int length)
  76 {
  77         const pktap_header_t *hdr;
  78         uint32_t dlt, hdrlen;
  79
  80         hdr = (const pktap_header_t *)bp;
  81
  82         dlt = EXTRACT_LE_32BITS(&hdr->pkt_dlt);
  83         hdrlen = EXTRACT_LE_32BITS(&hdr->pkt_len);
  84         if (!ndo->ndo_qflag) {
  85                 ND_PRINT((ndo,", DLT %s (%d) len %d",
  86                           pcap_datalink_val_to_name(dlt), dlt, hdrlen));
  87         } else {
  88                 ND_PRINT((ndo,", %s", pcap_datalink_val_to_name(dlt)));
  89         }
  90
  91         ND_PRINT((ndo, ", length %u: ", length));
  92 }
  93
  94 /*
  95  * This is the top level routine of the printer.  'p' points
  96  * to the ether header of the packet, 'h->ts' is the timestamp,
  97  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
  98  * is the number of bytes actually captured.
  99  */
 100 u_int
 101 pktap_if_print(netdissect_options *ndo,
 102                const struct pcap_pkthdr *h, const u_char *p)
 103 {
 104         uint32_t dlt, hdrlen, rectype;
 105         u_int caplen = h->caplen;
 106         u_int length = h->len;
 107         if_ndo_printer ndo_printer;
 108         if_printer printer;
 109         pktap_header_t *hdr;
 110
 111         if (caplen < sizeof(pktap_header_t) || length < sizeof(pktap_header_t)) {
 112                 ND_PRINT((ndo, "[|pktap]"));
 113                 return (0);
 114         }
 115         hdr = (pktap_header_t *)p;
 116         dlt = EXTRACT_LE_32BITS(&hdr->pkt_dlt);
 117         hdrlen = EXTRACT_LE_32BITS(&hdr->pkt_len);
 118         if (hdrlen < sizeof(pktap_header_t)) {
 119                 /*
 120                  * Claimed header length < structure length.
 121                  * XXX - does this just mean some fields aren't
 122                  * being supplied, or is it truly an error (i.e.,
 123                  * is the length supplied so that the header can
 124                  * be expanded in the future)?
 125                  */
 126                 ND_PRINT((ndo, "[|pktap]"));
 127                 return (0);
 128         }
 129         if (caplen < hdrlen || length < hdrlen) {
 130                 ND_PRINT((ndo, "[|pktap]"));
 131                 return (hdrlen);
 132         }
 133
 134         if (ndo->ndo_eflag)
 135                 pktap_header_print(ndo, p, length);
 136
 137         length -= hdrlen;
 138         caplen -= hdrlen;
 139         p += hdrlen;
 140
 141         rectype = EXTRACT_LE_32BITS(&hdr->pkt_rectype);
 142         switch (rectype) {
 143
 144         case PKT_REC_NONE:
 145                 ND_PRINT((ndo, "no data"));
 146                 break;
 147
 148         case PKT_REC_PACKET:
 149                 if ((printer = lookup_printer(dlt)) != NULL) {
 150                         printer(h, p);
 151                 } else if ((ndo_printer = lookup_ndo_printer(dlt)) != NULL) {
 152                         ndo_printer(ndo, h, p);
 153                 } else {
 154                         if (!ndo->ndo_eflag)
 155                                 pktap_header_print(ndo, (u_char *)hdr,
 156                                                 length + hdrlen);
 157
 158                         if (!ndo->ndo_suppress_default_print)
 159                                 ND_DEFAULTPRINT(p, caplen);
 160                 }
 161                 break;
 162         }
 163
 164         return (hdrlen);
 165 }
 166
 167 /*
 168  * Local Variables:
 169  * c-style: whitesmith
 170  * c-basic-offset: 8
 171  * End:
 172  */
 173
 174 #endif /* DLT_PKTAP */