The Tcpdump Group git mirrors - tcpdump/blob - print-zep.c

   1 /*
   2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
   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 /* \summary: ZigBee Encapsulation Protocol (ZEP) printer */
  23
  24 #ifdef HAVE_CONFIG_H
  25 #include <config.h>
  26 #endif
  27
  28 #include "netdissect-stdinc.h"
  29
  30 #define ND_LONGJMP_FROM_TCHECK
  31 #include "netdissect.h"
  32
  33 #include "extract.h"
  34
  35 /* From wireshark packet-zep.c:
  36  *
  37  ***********************************************************************
  38  *
  39  * ZEP Packets must be received in the following format:
  40  *
  41  * |UDP Header|  ZEP Header |IEEE 802.15.4 Packet|
  42  * | 8 bytes  | 16/32 bytes |    <= 127 bytes    |
  43  *
  44  ***********************************************************************
  45  *
  46  * ZEP v1 Header will have the following format:
  47  * |Preamble|Version|Channel ID|Device ID|CRC/LQI Mode|LQI Val|Reserved|Length|
  48  * |2 bytes |1 byte |  1 byte  | 2 bytes |   1 byte   |1 byte |7 bytes |1 byte|
  49  *
  50  * ZEP v2 Header will have the following format (if type=1/Data):
  51  * |Prmbl|Ver  |Type |ChnlID|DevID|C/L Mode|LQI|NTP TS|Seq#|Res |Len|
  52  * | 2   | 1   | 1   | 1    | 2   | 1      | 1 | 8    | 4  | 10 | 1 |
  53  *
  54  * ZEP v2 Header will have the following format (if type=2/Ack):
  55  * |Preamble|Version| Type |Sequence#|
  56  * |2 bytes |1 byte |1 byte| 4 bytes |
  57  *------------------------------------------------------------
  58  */
  59
  60 #define     JAN_1970        2208988800U
  61
  62 /* Print timestamp */
  63 static void zep_print_ts(netdissect_options *ndo, const u_char *p)
  64 {
  65         int32_t i;
  66         uint32_t uf;
  67         uint32_t f;
  68         float ff;
  69
  70         i = GET_BE_U_4(p);
  71         uf = GET_BE_U_4(p + 4);
  72         ff = (float) uf;
  73         if (ff < 0.0)           /* some compilers are buggy */
  74                 ff += FMAXINT;
  75         ff = (float) (ff / FMAXINT); /* shift radix point by 32 bits */
  76         f = (uint32_t) (ff * 1000000000.0);  /* treat fraction as parts per
  77                                                 billion */
  78         ND_PRINT("%u.%09d", i, f);
  79
  80         /*
  81          * print the time in human-readable format.
  82          */
  83         if (i) {
  84                 time_t seconds = i - JAN_1970;
  85                 char time_buf[128];
  86
  87                 ND_PRINT(" (%s)",
  88                     nd_format_time(time_buf, sizeof (time_buf), "%Y-%m-%d %H:%M:%S",
  89                       localtime(&seconds)));
  90         }
  91 }
  92
  93 /*
  94  * Main function to print packets.
  95  */
  96
  97 void
  98 zep_print(netdissect_options *ndo,
  99           const u_char *bp, u_int len)
 100 {
 101         uint8_t version, inner_len;
 102         uint32_t seq_no;
 103
 104         ndo->ndo_protocol = "zep";
 105
 106         nd_print_protocol_caps(ndo);
 107
 108         /* Preamble Code (must be "EX") */
 109         if (GET_U_1(bp) != 'E' || GET_U_1(bp + 1) != 'X') {
 110                 ND_PRINT(" [Preamble Code: ");
 111                 fn_print_char(ndo, GET_U_1(bp));
 112                 fn_print_char(ndo, GET_U_1(bp + 1));
 113                 ND_PRINT("]");
 114                 nd_print_invalid(ndo);
 115                 return;
 116         }
 117
 118         version = GET_U_1(bp + 2);
 119         ND_PRINT("v%u ", version);
 120
 121         if (version == 1) {
 122                 /* ZEP v1 packet. */
 123                 ND_ICHECK_U(len, <, 16);
 124                 ND_PRINT("Channel ID %u, Device ID 0x%04x, ",
 125                          GET_U_1(bp + 3), GET_BE_U_2(bp + 4));
 126                 if (GET_U_1(bp + 6))
 127                         ND_PRINT("CRC, ");
 128                 else
 129                         ND_PRINT("LQI %u, ", GET_U_1(bp + 7));
 130                 inner_len = GET_U_1(bp + 15);
 131                 ND_PRINT("inner len = %u", inner_len);
 132
 133                 bp += 16;
 134                 len -= 16;
 135         } else {
 136                 /* ZEP v2 packet. */
 137                 if (GET_U_1(bp + 3) == 2) {
 138                         /* ZEP v2 ack. */
 139                         ND_ICHECK_U(len, <, 8);
 140                         seq_no = GET_BE_U_4(bp + 4);
 141                         ND_PRINT("ACK, seq# = %u", seq_no);
 142                         inner_len = 0;
 143                         bp += 8;
 144                         len -= 8;
 145                 } else {
 146                         /* ZEP v2 data, or some other. */
 147                         ND_ICHECK_U(len, <, 32);
 148                         ND_PRINT("Type %u, Channel ID %u, Device ID 0x%04x, ",
 149                                  GET_U_1(bp + 3), GET_U_1(bp + 4),
 150                                  GET_BE_U_2(bp + 5));
 151                         if (GET_U_1(bp + 7))
 152                                 ND_PRINT("CRC, ");
 153                         else
 154                                 ND_PRINT("LQI %u, ", GET_U_1(bp + 8));
 155
 156                         zep_print_ts(ndo, bp + 9);
 157                         seq_no = GET_BE_U_4(bp + 17);
 158                         inner_len = GET_U_1(bp + 31);
 159                         ND_PRINT(", seq# = %u, inner len = %u",
 160                                  seq_no, inner_len);
 161                         bp += 32;
 162                         len -= 32;
 163                 }
 164         }
 165
 166         if (inner_len != 0) {
 167                 /* Call 802.15.4 dissector. */
 168                 ND_PRINT("\n\t");
 169                 if (ieee802_15_4_print(ndo, bp, inner_len)) {
 170                         ND_TCHECK_LEN(bp, len);
 171                         bp += len;
 172                         len = 0;
 173                 }
 174         }
 175
 176         if (!ndo->ndo_suppress_default_print)
 177                 ND_DEFAULTPRINT(bp, len);
 178         return;
 179 invalid:
 180         nd_print_invalid(ndo);
 181 }