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"
43 #include "netdissect.h"
44 #include "addrtoname.h"
50 * Based on ntp.h from the U of MD implementation
51 * This file is based on Version 2 of the NTP spec (RFC1119).
56 * 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
57 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
58 * |LI | VN |Mode | Stratum | Poll | Precision |
59 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
61 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
63 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
64 * | Reference Identifier |
65 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
67 * | Reference Timestamp (64) |
69 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
71 * | Originate Timestamp (64) |
73 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
75 * | Receive Timestamp (64) |
77 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
79 * | Transmit Timestamp (64) |
81 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
82 * | Key Identifier (optional) (32) |
83 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
86 * | Message Digest (optional) (128) |
89 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
92 /* Length of the NTP data message with the mandatory fields ("the header")
93 * and without any optional fields (extension, Key Identifier,
96 #define NTP_TIMEMSG_MINLEN 48U
98 struct ntp_time_data {
99 nd_uint8_t status; /* status of local clock and leap info */
100 nd_uint8_t stratum; /* Stratum level */
101 nd_int8_t ppoll; /* poll value */
103 struct s_fixedpt root_delay;
104 struct s_fixedpt root_dispersion;
106 struct l_fixedpt ref_timestamp;
107 struct l_fixedpt org_timestamp;
108 struct l_fixedpt rec_timestamp;
109 struct l_fixedpt xmt_timestamp;
111 nd_uint8_t message_digest[20];
114 * Leap Second Codes (high order two bits)
116 #define NO_WARNING 0x00 /* no warning */
117 #define PLUS_SEC 0x40 /* add a second (61 seconds) */
118 #define MINUS_SEC 0x80 /* minus a second (59 seconds) */
119 #define ALARM 0xc0 /* alarm condition (clock unsynchronized) */
122 * Clock Status Bits that Encode Version
124 #define NTPVERSION_1 0x08
125 #define VERSIONMASK 0x38
126 #define VERSIONSHIFT 3
127 #define LEAPMASK 0xc0
130 #undef MODEMASK /* Solaris sucks */
132 #define MODEMASK 0x07
138 #define MODE_UNSPEC 0 /* unspecified */
139 #define MODE_SYM_ACT 1 /* symmetric active */
140 #define MODE_SYM_PAS 2 /* symmetric passive */
141 #define MODE_CLIENT 3 /* client */
142 #define MODE_SERVER 4 /* server */
143 #define MODE_BROADCAST 5 /* broadcast */
144 #define MODE_CONTROL 6 /* control message */
145 #define MODE_RES2 7 /* reserved */
148 * Stratum Definitions
150 #define UNSPECIFIED 0
151 #define PRIM_REF 1 /* radio clock */
152 #define INFO_QUERY 62 /* **** THIS implementation dependent **** */
153 #define INFO_REPLY 63 /* **** THIS implementation dependent **** */
155 static void p_sfix(netdissect_options *ndo, const struct s_fixedpt *);
156 static void p_ntp_delta(netdissect_options *, const struct l_fixedpt *, const struct l_fixedpt *);
157 static void p_poll(netdissect_options *, const int);
159 static const struct tok ntp_mode_values[] = {
160 { MODE_UNSPEC, "unspecified" },
161 { MODE_SYM_ACT, "symmetric active" },
162 { MODE_SYM_PAS, "symmetric passive" },
163 { MODE_CLIENT, "Client" },
164 { MODE_SERVER, "Server" },
165 { MODE_BROADCAST, "Broadcast" },
166 { MODE_CONTROL, "Control Message" },
167 { MODE_RES2, "Reserved" },
171 static const struct tok ntp_leapind_values[] = {
174 { MINUS_SEC, "-1s" },
175 { ALARM, "clock unsynchronized" },
179 static const struct tok ntp_stratum_values[] = {
180 { UNSPECIFIED, "unspecified" },
181 { PRIM_REF, "primary reference" },
185 /* draft-ietf-ntp-mode-6-cmds-02
187 * 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
188 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
189 * |LI | VN |Mode |R|E|M| OpCode | Sequence Number |
190 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
191 * | Status | Association ID |
192 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
194 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
196 * / Data (up to 468 bytes) /
198 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
199 * | Padding (optional) |
200 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
202 * / Authenticator (optional, 96 bytes) /
204 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
206 * Figure 1: NTP Control Message Header
209 /* Length of the NTP control message with the mandatory fields ("the header")
210 * and without any optional fields (Data, Padding, Authenticator).
212 #define NTP_CTRLMSG_MINLEN 12U
214 struct ntp_control_data {
215 nd_uint8_t magic; /* LI, VN, Mode */
216 nd_uint8_t control; /* R, E, M, OpCode */
217 nd_uint16_t sequence; /* Sequence Number */
218 nd_uint16_t status; /* Status */
219 nd_uint16_t assoc; /* Association ID */
220 nd_uint16_t offset; /* Offset */
221 nd_uint16_t count; /* Count */
222 nd_uint8_t data[564]; /* Data, [Padding, [Authenticator]] */
226 * Print NTP time requests and responses
229 ntp_time_print(netdissect_options *ndo,
230 const struct ntp_time_data *bp, u_int length)
234 if (length < NTP_TIMEMSG_MINLEN)
237 stratum = GET_U_1(bp->stratum);
238 ND_PRINT(", Stratum %u (%s)",
240 tok2str(ntp_stratum_values, (stratum >=2 && stratum<=15) ? "secondary reference" : "reserved", stratum));
242 ND_PRINT(", poll %d", GET_S_1(bp->ppoll));
243 p_poll(ndo, GET_S_1(bp->ppoll));
245 ND_PRINT(", precision %d", GET_S_1(bp->precision));
247 ND_TCHECK_SIZE(&bp->root_delay);
248 ND_PRINT("\n\tRoot Delay: ");
249 p_sfix(ndo, &bp->root_delay);
251 ND_TCHECK_SIZE(&bp->root_dispersion);
252 ND_PRINT(", Root dispersion: ");
253 p_sfix(ndo, &bp->root_dispersion);
255 ND_TCHECK_4(bp->refid);
256 ND_PRINT(", Reference-ID: ");
257 /* Interpretation depends on stratum */
261 ND_PRINT("(unspec)");
265 if (nd_printn(ndo, (const u_char *)&(bp->refid), 4, ndo->ndo_snapend))
270 ND_PRINT("%s INFO_QUERY", GET_IPADDR_STRING(bp->refid));
271 /* this doesn't have more content */
275 ND_PRINT("%s INFO_REPLY", GET_IPADDR_STRING(bp->refid));
276 /* this is too complex to be worth printing */
280 /* In NTPv4 (RFC 5905) refid is an IPv4 address or first 32 bits of
281 MD5 sum of IPv6 address */
282 ND_PRINT("0x%08x", GET_BE_U_4(bp->refid));
286 ND_TCHECK_SIZE(&bp->ref_timestamp);
287 ND_PRINT("\n\t Reference Timestamp: ");
288 p_ntp_time(ndo, &(bp->ref_timestamp));
290 ND_TCHECK_SIZE(&bp->org_timestamp);
291 ND_PRINT("\n\t Originator Timestamp: ");
292 p_ntp_time(ndo, &(bp->org_timestamp));
294 ND_TCHECK_SIZE(&bp->rec_timestamp);
295 ND_PRINT("\n\t Receive Timestamp: ");
296 p_ntp_time(ndo, &(bp->rec_timestamp));
298 ND_TCHECK_SIZE(&bp->xmt_timestamp);
299 ND_PRINT("\n\t Transmit Timestamp: ");
300 p_ntp_time(ndo, &(bp->xmt_timestamp));
302 ND_PRINT("\n\t Originator - Receive Timestamp: ");
303 p_ntp_delta(ndo, &(bp->org_timestamp), &(bp->rec_timestamp));
305 ND_PRINT("\n\t Originator - Transmit Timestamp: ");
306 p_ntp_delta(ndo, &(bp->org_timestamp), &(bp->xmt_timestamp));
308 /* FIXME: this code is not aware of any extension fields */
309 if (length == NTP_TIMEMSG_MINLEN + 4) { /* Optional: key-id (crypto-NAK) */
310 ND_PRINT("\n\tKey id: %u", GET_BE_U_4(bp->key_id));
311 } else if (length == NTP_TIMEMSG_MINLEN + 4 + 16) { /* Optional: key-id + 128-bit digest */
312 ND_PRINT("\n\tKey id: %u", GET_BE_U_4(bp->key_id));
313 ND_TCHECK_LEN(bp->message_digest, 16);
314 ND_PRINT("\n\tAuthentication: %08x%08x%08x%08x",
315 GET_BE_U_4(bp->message_digest),
316 GET_BE_U_4(bp->message_digest + 4),
317 GET_BE_U_4(bp->message_digest + 8),
318 GET_BE_U_4(bp->message_digest + 12));
319 } else if (length == NTP_TIMEMSG_MINLEN + 4 + 20) { /* Optional: key-id + 160-bit digest */
320 ND_PRINT("\n\tKey id: %u", GET_BE_U_4(bp->key_id));
321 ND_TCHECK_LEN(bp->message_digest, 20);
322 ND_PRINT("\n\tAuthentication: %08x%08x%08x%08x%08x",
323 GET_BE_U_4(bp->message_digest),
324 GET_BE_U_4(bp->message_digest + 4),
325 GET_BE_U_4(bp->message_digest + 8),
326 GET_BE_U_4(bp->message_digest + 12),
327 GET_BE_U_4(bp->message_digest + 16));
328 } else if (length > NTP_TIMEMSG_MINLEN) {
329 ND_PRINT("\n\t(%u more bytes after the header)", length - NTP_TIMEMSG_MINLEN);
334 nd_print_invalid(ndo);
335 ND_TCHECK_LEN(bp, length);
343 * Print NTP control message requests and responses
346 ntp_control_print(netdissect_options *ndo,
347 const struct ntp_control_data *cd, u_int length)
349 uint8_t control, R, E, M, opcode;
350 uint16_t sequence, status, assoc, offset, count;
352 if (length < NTP_CTRLMSG_MINLEN)
355 control = GET_U_1(cd->control);
356 R = (control & 0x80) != 0;
357 E = (control & 0x40) != 0;
358 M = (control & 0x20) != 0;
359 opcode = control & 0x1f;
360 ND_PRINT(", %s, %s, %s, OpCode=%u\n",
361 R ? "Response" : "Request", E ? "Error" : "OK",
362 M ? "More" : "Last", opcode);
364 sequence = GET_BE_U_2(cd->sequence);
365 ND_PRINT("\tSequence=%hu", sequence);
367 status = GET_BE_U_2(cd->status);
368 ND_PRINT(", Status=%#hx", status);
370 assoc = GET_BE_U_2(cd->assoc);
371 ND_PRINT(", Assoc.=%hu", assoc);
373 offset = GET_BE_U_2(cd->offset);
374 ND_PRINT(", Offset=%hu", offset);
376 count = GET_BE_U_2(cd->count);
377 ND_PRINT(", Count=%hu", count);
379 if (NTP_CTRLMSG_MINLEN + count > length)
382 ND_TCHECK_LEN(cd->data, count);
383 ND_PRINT("\n\tTO-BE-DONE: data not interpreted");
388 nd_print_invalid(ndo);
389 ND_TCHECK_LEN(cd, length);
397 struct ntp_time_data td;
398 struct ntp_control_data cd;
402 * Print NTP requests, handling the common VN, LI, and Mode
405 ntp_print(netdissect_options *ndo,
406 const u_char *cp, u_int length)
408 const union ntpdata *bp = (const union ntpdata *)cp;
409 u_int mode, version, leapind;
412 ndo->ndo_protocol = "ntp";
413 status = GET_U_1(bp->td.status);
415 version = (status & VERSIONMASK) >> VERSIONSHIFT;
416 ND_PRINT("NTPv%u", version);
418 mode = (status & MODEMASK) >> MODESHIFT;
419 if (!ndo->ndo_vflag) {
420 ND_PRINT(", %s, length %u",
421 tok2str(ntp_mode_values, "Unknown mode", mode),
426 ND_PRINT(", %s, length %u\n",
427 tok2str(ntp_mode_values, "Unknown mode", mode), length);
429 /* leapind = (status & LEAPMASK) >> LEAPSHIFT; */
430 leapind = (status & LEAPMASK);
431 ND_PRINT("\tLeap indicator: %s (%u)",
432 tok2str(ntp_leapind_values, "Unknown", leapind),
443 ntp_time_print(ndo, &bp->td, length);
447 ntp_control_print(ndo, &bp->cd, length);
451 break; /* XXX: not implemented! */
456 p_sfix(netdissect_options *ndo,
457 const struct s_fixedpt *sfp)
463 i = GET_BE_U_2(sfp->int_part);
464 f = GET_BE_U_2(sfp->fraction);
465 ff = f / 65536.0; /* shift radix point by 16 bits */
466 f = (int)(ff * 1000000.0); /* Treat fraction as parts per million */
467 ND_PRINT("%d.%06d", i, f);
470 /* Prints time difference between *lfp and *olfp */
472 p_ntp_delta(netdissect_options *ndo,
473 const struct l_fixedpt *olfp,
474 const struct l_fixedpt *lfp)
483 u = GET_BE_U_4(lfp->int_part);
484 ou = GET_BE_U_4(olfp->int_part);
485 uf = GET_BE_U_4(lfp->fraction);
486 ouf = GET_BE_U_4(olfp->fraction);
487 if (ou == 0 && ouf == 0) {
488 p_ntp_time(ndo, lfp);
492 if (u > ou) { /* new is definitely greater than old */
496 if (ouf > uf) /* must borrow from high-order bits */
498 } else if (u < ou) { /* new is definitely less than old */
502 if (uf > ouf) /* must borrow from the high-order bits */
504 } else { /* int_part is zero */
516 if (ff < 0.0) /* some compilers are buggy */
518 ff = ff / FMAXINT; /* shift radix point by 32 bits */
519 f = (uint32_t)(ff * 1000000000.0); /* treat fraction as parts per billion */
520 ND_PRINT("%s%u.%09u", signbit ? "-" : "+", i, f);
523 /* Prints polling interval in log2 as seconds or fraction of second */
525 p_poll(netdissect_options *ndo,
526 const int poll_interval)
528 if (poll_interval <= -32 || poll_interval >= 32)
531 if (poll_interval >= 0)
532 ND_PRINT(" (%us)", 1U << poll_interval);
534 ND_PRINT(" (1/%us)", 1U << -poll_interval);