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/*
 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that: (1) source code distributions
 * retain the above copyright notice and this paragraph in its entirety, (2)
 * distributions including binary code include the above copyright notice and
 * this paragraph in its entirety in the documentation or other materials
 * provided with the distribution, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
 * the University nor the names of its contributors may be used to endorse
 * or promote products derived from this software without specific prior
 * written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#define NETDISSECT_REWORKED
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <tcpdump-stdinc.h>

#include "interface.h"
#include "extract.h"

#ifdef DLT_PKTAP

/*
 * XXX - these are little-endian in the captures I've seen, but Apple
 * no longer make any big-endian machines (Macs use x86, iOS machines
 * use ARM and run it little-endian), so that might be by definition
 * or they might be host-endian.
 *
 * If a big-endian PKTAP file ever shows up, and it comes from a
 * big-endian machine, presumably these are host-endian, and we need
 * to just fetch the fields directly in tcpdump but byte-swap them
 * to host byte order in libpcap.
 */
typedef struct pktap_header {
        uint32_t        pkt_len;        /* length of pktap header */
        uint32_t        pkt_rectype;    /* type of record */
        uint32_t        pkt_dlt;        /* DLT type of this packet */
        char            pkt_ifname[24]; /* interface name */
        uint32_t        pkt_flags;
        uint32_t        pkt_pfamily;    /* "protocol family" */
        uint32_t        pkt_llhdrlen;   /* link-layer header length? */
        uint32_t        pkt_lltrlrlen;  /* link-layer trailer length? */
        uint32_t        pkt_pid;        /* process ID */
        char            pkt_cmdname[20]; /* command name */
        uint32_t        pkt_svc_class;  /* "service class" */
        uint16_t        pkt_iftype;     /* "interface type" */
        uint16_t        pkt_ifunit;     /* unit number of interface? */
        uint32_t        pkt_epid;       /* "effective process ID" */
        char            pkt_ecmdname[20]; /* "effective command name" */
} pktap_header_t;

/*
 * Record types.
 */
#define PKT_REC_NONE    0        /* nothing follows the header */
#define PKT_REC_PACKET  1       /* a packet follows the header */

static inline void
pktap_header_print(netdissect_options *ndo, const u_char *bp, u_int length)
{
        const pktap_header_t *hdr;
        uint32_t dlt, hdrlen;

        hdr = (const pktap_header_t *)bp;

        dlt = EXTRACT_LE_32BITS(&hdr->pkt_dlt);
        hdrlen = EXTRACT_LE_32BITS(&hdr->pkt_len);
        if (!ndo->ndo_qflag) {
                ND_PRINT((ndo,", DLT %s (%d) len %d",
                          pcap_datalink_val_to_name(dlt), dlt, hdrlen));
        } else {
                ND_PRINT((ndo,", %s", pcap_datalink_val_to_name(dlt)));
        }

        ND_PRINT((ndo, ", length %u: ", length));
}

/*
 * This is the top level routine of the printer.  'p' points
 * to the ether header of the packet, 'h->ts' is the timestamp,
 * 'h->len' is the length of the packet off the wire, and 'h->caplen'
 * is the number of bytes actually captured.
 */
u_int
pktap_if_print(netdissect_options *ndo,
               const struct pcap_pkthdr *h, const u_char *p)
{
        uint32_t dlt, hdrlen, rectype;
        u_int caplen = h->caplen;
        u_int length = h->len;
        if_ndo_printer ndo_printer;
        if_printer printer;
        pktap_header_t *hdr;

        if (caplen < sizeof(pktap_header_t) || length < sizeof(pktap_header_t)) {
                ND_PRINT((ndo, "[|pktap]"));
                return (0);
        }
        hdr = (pktap_header_t *)p;
        dlt = EXTRACT_LE_32BITS(&hdr->pkt_dlt);
        hdrlen = EXTRACT_LE_32BITS(&hdr->pkt_len);
        if (hdrlen < sizeof(pktap_header_t)) {
                /*
                 * Claimed header length < structure length.
                 * XXX - does this just mean some fields aren't
                 * being supplied, or is it truly an error (i.e.,
                 * is the length supplied so that the header can
                 * be expanded in the future)?
                 */
                ND_PRINT((ndo, "[|pktap]"));
                return (0);
        }
        if (caplen < hdrlen || length < hdrlen) {
                ND_PRINT((ndo, "[|pktap]"));
                return (hdrlen);
        }

        if (ndo->ndo_eflag)
                pktap_header_print(ndo, p, length);

        length -= hdrlen;
        caplen -= hdrlen;
        p += hdrlen;

        rectype = EXTRACT_LE_32BITS(&hdr->pkt_rectype);
        switch (rectype) {

        case PKT_REC_NONE:
                ND_PRINT((ndo, "no data"));
                break;

        case PKT_REC_PACKET:
                if ((printer = lookup_printer(dlt)) != NULL) {
                        printer(h, p);
                } else if ((ndo_printer = lookup_ndo_printer(dlt)) != NULL) {
                        ndo_printer(ndo, h, p);
                } else {
                        if (!ndo->ndo_eflag)
                                pktap_header_print(ndo, (u_char *)hdr,
                                                length + hdrlen);

                        if (!ndo->ndo_suppress_default_print)
                                ND_DEFAULTPRINT(p, caplen);
                }
                break;
        }

        return (hdrlen);
}

/*
 * Local Variables:
 * c-style: whitesmith
 * c-basic-offset: 8
 * End:
 */

#endif /* DLT_PKTAP */