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 */
63static 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
97void
98zep_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_LCHECK_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_LCHECK_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_LCHECK_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;
179invalid:
180	nd_print_invalid(ndo);
181}
182