/*
 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
 *	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.
 */


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

#include <netdissect-stdinc.h>

#include "netdissect.h"

#include "extract.h"

/* From wireshark packet-zep.c:
 *
 ***********************************************************************
 *
 * ZEP Packets must be received in the following format:
 *
 * |UDP Header|  ZEP Header |IEEE 802.15.4 Packet|
 * | 8 bytes  | 16/32 bytes |    <= 127 bytes    |
 *
 ***********************************************************************
 *
 * ZEP v1 Header will have the following format:
 *
 * |Preamble|Version|Channel ID|Device ID|CRC/LQI Mode|LQI Val|Reserved|Length|
 * |2 bytes |1 byte |  1 byte  | 2 bytes |   1 byte   |1 byte |7 bytes |1 byte|
 *
 * ZEP v2 Header will have the following format (if type=1/Data):
 * |Prmbl|Ver  |Type |ChnlID|DevID|C/L Mode|LQI|NTP TS|Seq#|Res |Len|
 * | 2   | 1   | 1   | 1    | 2   | 1      | 1 | 8    | 4  | 10 | 1 |
 *
 * ZEP v2 Header will have the following format (if type=2/Ack):
 * |Preamble|Version| Type |Sequence#|
 * |2 bytes |1 byte |1 byte| 4 bytes |
 *------------------------------------------------------------
 */

#define     FMAXINT (4294967296.0)  /* floating point rep. of MAXINT */
#define     JAN_1970        2208988800U

/* Print timestamp */
static void zep_print_ts(netdissect_options *ndo, const u_char *p)
{
  int32_t i;
  uint32_t uf;
  uint32_t f;
  float ff;

  i = EXTRACT_32BITS(p);
  uf = EXTRACT_32BITS(p + 4);
  ff = uf;
  if (ff < 0.0)           /* some compilers are buggy */
    ff += FMAXINT;
  ff = ff / FMAXINT;      /* shift radix point by 32 bits */
  f = ff * 1000000000.0;  /* treat fraction as parts per billion */
  ND_PRINT((ndo, "%u.%09d", i, f));

#ifdef HAVE_STRFTIME
  /*
   * print the time in human-readable format.
   */
  if (i) {
    time_t seconds = i - JAN_1970;
    struct tm *tm;
    char time_buf[128];

    tm = localtime(&seconds);
    strftime(time_buf, sizeof (time_buf), "%Y/%m/%d %H:%M:%S", tm);
    ND_PRINT((ndo, " (%s)", time_buf));
  }
#endif
}

/*
 * Main function to print packets.
 */
 
void
zep_print(netdissect_options *ndo,
	  const u_char *bp, u_int len)
{
    uint8_t version, inner_len;
    uint32_t seq_no;
    
    ND_PRINT((ndo, "ZEP"));
    
    ND_TCHECK2(*bp, 8);

    if (*bp != 'E' || *(bp+1) != 'X') goto trunc;
    
    version = *(bp + 2);
    ND_PRINT((ndo, "v%d ", version));

    if (version == 1) {
      /* ZEP v1 packet. */
      ND_TCHECK2(*bp, 16);
      ND_PRINT((ndo, "Channel ID %d, Device ID 0x%04x, ",
		*(bp + 3), EXTRACT_16BITS(bp + 4)));
      if (*(bp + 6))
	ND_PRINT((ndo, "CRC, "));
      else
	ND_PRINT((ndo, "LQI %d, ", *(bp + 7)));
      inner_len = *(bp + 15);
      ND_PRINT((ndo, "inner len = %d", inner_len));

      bp += 16;
      len -= 16;
    } else {
      /* ZEP v2 packet. */
      if (*(bp + 3) == 2) {
	/* ZEP v2 ack. */
	seq_no = EXTRACT_32BITS(bp + 4);
	ND_PRINT((ndo, "ACK, seq# = %d", seq_no));
	inner_len = 0;
	bp += 8;
	len -= 8;
      } else {
	/* ZEP v2 data, or some other. */
	ND_TCHECK2(*bp, 32);
	
	ND_PRINT((ndo, "Type %d, Channel ID %d, Device ID 0x%04x, ",
		  *(bp + 3), *(bp + 4), EXTRACT_16BITS(bp + 5)));
	if (*(bp + 7))
	  ND_PRINT((ndo, "CRC, "));
	else
	  ND_PRINT((ndo, "LQI %d, ", *(bp + 8)));
	
	zep_print_ts(ndo, bp + 9);
	seq_no = EXTRACT_32BITS(bp + 17);
	inner_len = *(bp + 31);
	ND_PRINT((ndo, ", seq# = %d, inner len = %d", seq_no, inner_len));
	bp += 32;
	len -= 32;
      }
    }

    if (inner_len != 0) {
      /* Call 802.15.4 dissector. */
      ND_PRINT((ndo, "\n\t"));
      if (ieee802_15_4_print(ndo, bp, inner_len)) {
	bp += len;
	len = 0;
      }
    }
    
    if (!ndo->ndo_suppress_default_print)
      ND_DEFAULTPRINT(bp, len);
    
    return;    
 trunc:
    ND_PRINT((ndo, " [|ZEP]"));
}