2 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
3 * The Regents of the University of California. All rights reserved.
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
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.
21 * By Jeffrey Mogul/DECWRL
22 * loosely based on print-bootp.c
25 /* \summary: Network Time Protocol (NTP) printer */
39 #include "netdissect-stdinc.h"
45 #include "netdissect.h"
46 #include "addrtoname.h"
52 * Based on ntp.h from the U of MD implementation
53 * This file is based on Version 2 of the NTP spec (RFC1119).
58 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
59 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
60 * |LI | VN |Mode | Stratum | Poll | Precision |
61 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
63 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
65 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
66 * | Reference Identifier |
67 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
69 * | Reference Timestamp (64) |
71 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
73 * | Originate Timestamp (64) |
75 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
77 * | Receive Timestamp (64) |
79 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
81 * | Transmit Timestamp (64) |
83 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
84 * | Key Identifier (optional) (32) |
85 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
88 * | Message Digest (optional) (128) |
91 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
94 /* Length of the NTP data message with the mandatory fields ("the header")
95 * and without any optional fields (extension, Key Identifier,
98 #define NTP_TIMEMSG_MINLEN 48U
100 struct ntp_time_data {
101 nd_uint8_t status; /* status of local clock and leap info */
102 nd_uint8_t stratum; /* Stratum level */
103 nd_int8_t ppoll; /* poll value */
105 struct s_fixedpt root_delay;
106 struct s_fixedpt root_dispersion;
108 struct l_fixedpt ref_timestamp;
109 struct l_fixedpt org_timestamp;
110 struct l_fixedpt rec_timestamp;
111 struct l_fixedpt xmt_timestamp;
113 nd_uint8_t message_digest[20];
116 * Leap Second Codes (high order two bits)
118 #define NO_WARNING 0x00 /* no warning */
119 #define PLUS_SEC 0x40 /* add a second (61 seconds) */
120 #define MINUS_SEC 0x80 /* minus a second (59 seconds) */
121 #define ALARM 0xc0 /* alarm condition (clock unsynchronized) */
124 * Clock Status Bits that Encode Version
126 #define NTPVERSION_1 0x08
127 #define VERSIONMASK 0x38
128 #define VERSIONSHIFT 3
129 #define LEAPMASK 0xc0
132 #undef MODEMASK /* Solaris sucks */
134 #define MODEMASK 0x07
140 #define MODE_UNSPEC 0 /* unspecified */
141 #define MODE_SYM_ACT 1 /* symmetric active */
142 #define MODE_SYM_PAS 2 /* symmetric passive */
143 #define MODE_CLIENT 3 /* client */
144 #define MODE_SERVER 4 /* server */
145 #define MODE_BROADCAST 5 /* broadcast */
146 #define MODE_CONTROL 6 /* control message */
147 #define MODE_RES2 7 /* reserved */
150 * Stratum Definitions
152 #define UNSPECIFIED 0
153 #define PRIM_REF 1 /* radio clock */
154 #define INFO_QUERY 62 /* **** THIS implementation dependent **** */
155 #define INFO_REPLY 63 /* **** THIS implementation dependent **** */
157 static void p_sfix(netdissect_options *ndo, const struct s_fixedpt *);
158 static void p_ntp_delta(netdissect_options *, const struct l_fixedpt *, const struct l_fixedpt *);
159 static void p_poll(netdissect_options *, const int);
161 static const struct tok ntp_mode_values[] = {
162 { MODE_UNSPEC, "unspecified" },
163 { MODE_SYM_ACT, "symmetric active" },
164 { MODE_SYM_PAS, "symmetric passive" },
165 { MODE_CLIENT, "Client" },
166 { MODE_SERVER, "Server" },
167 { MODE_BROADCAST, "Broadcast" },
168 { MODE_CONTROL, "Control Message" },
169 { MODE_RES2, "Reserved" },
173 static const struct tok ntp_leapind_values[] = {
176 { MINUS_SEC, "-1s" },
177 { ALARM, "clock unsynchronized" },
181 static const struct tok ntp_stratum_values[] = {
182 { UNSPECIFIED, "unspecified" },
183 { PRIM_REF, "primary reference" },
187 /* draft-ietf-ntp-mode-6-cmds-02
189 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
190 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
191 * |LI | VN |Mode |R|E|M| OpCode | Sequence Number |
192 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
193 * | Status | Association ID |
194 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
196 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
198 * / Data (up to 468 bytes) /
200 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
201 * | Padding (optional) |
202 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
204 * / Authenticator (optional, 96 bytes) /
206 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
208 * Figure 1: NTP Control Message Header
211 /* Length of the NTP control message with the mandatory fields ("the header")
212 * and without any optional fields (Data, Padding, Authenticator).
214 #define NTP_CTRLMSG_MINLEN 12U
216 struct ntp_control_data {
217 nd_uint8_t magic; /* LI, VN, Mode */
218 nd_uint8_t control; /* R, E, M, OpCode */
219 nd_uint16_t sequence; /* Sequence Number */
220 nd_uint16_t status; /* Status */
221 nd_uint16_t assoc; /* Association ID */
222 nd_uint16_t offset; /* Offset */
223 nd_uint16_t count; /* Count */
224 nd_uint8_t data[564]; /* Data, [Padding, [Authenticator]] */
228 * Print NTP time requests and responses
231 ntp_time_print(netdissect_options *ndo,
232 const struct ntp_time_data *bp, u_int length)
236 if (length < NTP_TIMEMSG_MINLEN)
239 stratum = GET_U_1(bp->stratum);
240 ND_PRINT(", Stratum %u (%s)",
242 tok2str(ntp_stratum_values, (stratum >=2 && stratum<=15) ? "secondary reference" : "reserved", stratum));
244 ND_PRINT(", poll %d", GET_S_1(bp->ppoll));
245 p_poll(ndo, GET_S_1(bp->ppoll));
247 ND_PRINT(", precision %d", GET_S_1(bp->precision));
249 ND_TCHECK_SIZE(&bp->root_delay);
250 ND_PRINT("\n\tRoot Delay: ");
251 p_sfix(ndo, &bp->root_delay);
253 ND_TCHECK_SIZE(&bp->root_dispersion);
254 ND_PRINT(", Root dispersion: ");
255 p_sfix(ndo, &bp->root_dispersion);
257 ND_TCHECK_4(bp->refid);
258 ND_PRINT(", Reference-ID: ");
259 /* Interpretation depends on stratum */
263 ND_PRINT("(unspec)");
267 if (nd_printn(ndo, (const u_char *)&(bp->refid), 4, ndo->ndo_snapend))
272 ND_PRINT("%s INFO_QUERY", GET_IPADDR_STRING(bp->refid));
273 /* this doesn't have more content */
277 ND_PRINT("%s INFO_REPLY", GET_IPADDR_STRING(bp->refid));
278 /* this is too complex to be worth printing */
282 /* In NTPv4 (RFC 5905) refid is an IPv4 address or first 32 bits of
283 MD5 sum of IPv6 address */
284 ND_PRINT("0x%08x", GET_BE_U_4(bp->refid));
288 ND_TCHECK_SIZE(&bp->ref_timestamp);
289 ND_PRINT("\n\t Reference Timestamp: ");
290 p_ntp_time(ndo, &(bp->ref_timestamp));
292 ND_TCHECK_SIZE(&bp->org_timestamp);
293 ND_PRINT("\n\t Originator Timestamp: ");
294 p_ntp_time(ndo, &(bp->org_timestamp));
296 ND_TCHECK_SIZE(&bp->rec_timestamp);
297 ND_PRINT("\n\t Receive Timestamp: ");
298 p_ntp_time(ndo, &(bp->rec_timestamp));
300 ND_TCHECK_SIZE(&bp->xmt_timestamp);
301 ND_PRINT("\n\t Transmit Timestamp: ");
302 p_ntp_time(ndo, &(bp->xmt_timestamp));
304 ND_PRINT("\n\t Originator - Receive Timestamp: ");
305 p_ntp_delta(ndo, &(bp->org_timestamp), &(bp->rec_timestamp));
307 ND_PRINT("\n\t Originator - Transmit Timestamp: ");
308 p_ntp_delta(ndo, &(bp->org_timestamp), &(bp->xmt_timestamp));
310 /* FIXME: this code is not aware of any extension fields */
311 if (length == NTP_TIMEMSG_MINLEN + 4) { /* Optional: key-id (crypto-NAK) */
312 ND_PRINT("\n\tKey id: %u", GET_BE_U_4(bp->key_id));
313 } else if (length == NTP_TIMEMSG_MINLEN + 4 + 16) { /* Optional: key-id + 128-bit digest */
314 ND_PRINT("\n\tKey id: %u", GET_BE_U_4(bp->key_id));
315 ND_TCHECK_LEN(bp->message_digest, 16);
316 ND_PRINT("\n\tAuthentication: %08x%08x%08x%08x",
317 GET_BE_U_4(bp->message_digest),
318 GET_BE_U_4(bp->message_digest + 4),
319 GET_BE_U_4(bp->message_digest + 8),
320 GET_BE_U_4(bp->message_digest + 12));
321 } else if (length == NTP_TIMEMSG_MINLEN + 4 + 20) { /* Optional: key-id + 160-bit digest */
322 ND_PRINT("\n\tKey id: %u", GET_BE_U_4(bp->key_id));
323 ND_TCHECK_LEN(bp->message_digest, 20);
324 ND_PRINT("\n\tAuthentication: %08x%08x%08x%08x%08x",
325 GET_BE_U_4(bp->message_digest),
326 GET_BE_U_4(bp->message_digest + 4),
327 GET_BE_U_4(bp->message_digest + 8),
328 GET_BE_U_4(bp->message_digest + 12),
329 GET_BE_U_4(bp->message_digest + 16));
330 } else if (length > NTP_TIMEMSG_MINLEN) {
331 ND_PRINT("\n\t(%u more bytes after the header)", length - NTP_TIMEMSG_MINLEN);
336 nd_print_invalid(ndo);
337 ND_TCHECK_LEN(bp, length);
345 * Print NTP control message requests and responses
348 ntp_control_print(netdissect_options *ndo,
349 const struct ntp_control_data *cd, u_int length)
351 uint8_t control, R, E, M, opcode;
352 uint16_t sequence, status, assoc, offset, count;
354 if (length < NTP_CTRLMSG_MINLEN)
357 control = GET_U_1(cd->control);
358 R = (control & 0x80) != 0;
359 E = (control & 0x40) != 0;
360 M = (control & 0x20) != 0;
361 opcode = control & 0x1f;
362 ND_PRINT(", %s, %s, %s, OpCode=%u\n",
363 R ? "Response" : "Request", E ? "Error" : "OK",
364 M ? "More" : "Last", opcode);
366 sequence = GET_BE_U_2(cd->sequence);
367 ND_PRINT("\tSequence=%hu", sequence);
369 status = GET_BE_U_2(cd->status);
370 ND_PRINT(", Status=%#hx", status);
372 assoc = GET_BE_U_2(cd->assoc);
373 ND_PRINT(", Assoc.=%hu", assoc);
375 offset = GET_BE_U_2(cd->offset);
376 ND_PRINT(", Offset=%hu", offset);
378 count = GET_BE_U_2(cd->count);
379 ND_PRINT(", Count=%hu", count);
381 if (NTP_CTRLMSG_MINLEN + count > length)
384 ND_TCHECK_LEN(cd->data, count);
385 ND_PRINT("\n\tTO-BE-DONE: data not interpreted");
390 nd_print_invalid(ndo);
391 ND_TCHECK_LEN(cd, length);
399 struct ntp_time_data td;
400 struct ntp_control_data cd;
404 * Print NTP requests, handling the common VN, LI, and Mode
407 ntp_print(netdissect_options *ndo,
408 const u_char *cp, u_int length)
410 const union ntpdata *bp = (const union ntpdata *)cp;
411 u_int mode, version, leapind;
414 ndo->ndo_protocol = "ntp";
415 status = GET_U_1(bp->td.status);
417 version = (status & VERSIONMASK) >> VERSIONSHIFT;
418 ND_PRINT("NTPv%u", version);
420 mode = (status & MODEMASK) >> MODESHIFT;
421 if (!ndo->ndo_vflag) {
422 ND_PRINT(", %s, length %u",
423 tok2str(ntp_mode_values, "Unknown mode", mode),
428 ND_PRINT(", %s, length %u\n",
429 tok2str(ntp_mode_values, "Unknown mode", mode), length);
431 /* leapind = (status & LEAPMASK) >> LEAPSHIFT; */
432 leapind = (status & LEAPMASK);
433 ND_PRINT("\tLeap indicator: %s (%u)",
434 tok2str(ntp_leapind_values, "Unknown", leapind),
445 ntp_time_print(ndo, &bp->td, length);
449 ntp_control_print(ndo, &bp->cd, length);
453 break; /* XXX: not implemented! */
458 p_sfix(netdissect_options *ndo,
459 const struct s_fixedpt *sfp)
465 i = GET_BE_U_2(sfp->int_part);
466 f = GET_BE_U_2(sfp->fraction);
467 ff = f / 65536.0; /* shift radix point by 16 bits */
468 f = (int)(ff * 1000000.0); /* Treat fraction as parts per million */
469 ND_PRINT("%d.%06d", i, f);
472 /* Prints time difference between *lfp and *olfp */
474 p_ntp_delta(netdissect_options *ndo,
475 const struct l_fixedpt *olfp,
476 const struct l_fixedpt *lfp)
485 u = GET_BE_U_4(lfp->int_part);
486 ou = GET_BE_U_4(olfp->int_part);
487 uf = GET_BE_U_4(lfp->fraction);
488 ouf = GET_BE_U_4(olfp->fraction);
489 if (ou == 0 && ouf == 0) {
490 p_ntp_time(ndo, lfp);
494 if (u > ou) { /* new is definitely greater than old */
498 if (ouf > uf) /* must borrow from high-order bits */
500 } else if (u < ou) { /* new is definitely less than old */
504 if (uf > ouf) /* must borrow from the high-order bits */
506 } else { /* int_part is zero */
518 if (ff < 0.0) /* some compilers are buggy */
520 ff = ff / FMAXINT; /* shift radix point by 32 bits */
521 f = (uint32_t)(ff * 1000000000.0); /* treat fraction as parts per billion */
522 ND_PRINT("%s%u.%09u", signbit ? "-" : "+", i, f);
525 /* Prints polling interval in log2 as seconds or fraction of second */
527 p_poll(netdissect_options *ndo,
528 const int poll_interval)
530 if (poll_interval <= -32 || poll_interval >= 32)
533 if (poll_interval >= 0)
534 ND_PRINT(" (%us)", 1U << poll_interval);
536 ND_PRINT(" (1/%us)", 1U << -poll_interval);