1 /* 2 * Copyright (c) 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 * Format and print ntp packets. 22 * By Jeffrey Mogul/DECWRL 23 * loosely based on print-bootp.c 24 */ 25 26 #include <sys/cdefs.h> 27 #ifndef lint 28 __RCSID("$NetBSD: print-ntp.c,v 1.6 2017/01/24 23:29:14 christos Exp $"); 29 #endif 30 31 #ifdef HAVE_CONFIG_H 32 #include "config.h" 33 #endif 34 35 #include <netdissect-stdinc.h> 36 37 #ifdef HAVE_STRFTIME 38 #include <time.h> 39 #endif 40 41 #include "netdissect.h" 42 #include "addrtoname.h" 43 #include "extract.h" 44 45 /* 46 * Based on ntp.h from the U of MD implementation 47 * This file is based on Version 2 of the NTP spec (RFC1119). 48 */ 49 50 /* 51 * Definitions for the masses 52 */ 53 #define JAN_1970 2208988800U /* 1970 - 1900 in seconds */ 54 55 /* 56 * Structure definitions for NTP fixed point values 57 * 58 * 0 1 2 3 59 * 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 60 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 61 * | Integer Part | 62 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 63 * | Fraction Part | 64 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 65 * 66 * 0 1 2 3 67 * 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 68 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 69 * | Integer Part | Fraction Part | 70 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 71 */ 72 struct l_fixedpt { 73 uint32_t int_part; 74 uint32_t fraction; 75 }; 76 77 struct s_fixedpt { 78 uint16_t int_part; 79 uint16_t fraction; 80 }; 81 82 /* rfc2030 83 * 1 2 3 84 * 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 85 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 86 * |LI | VN |Mode | Stratum | Poll | Precision | 87 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 88 * | Root Delay | 89 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 90 * | Root Dispersion | 91 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 92 * | Reference Identifier | 93 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 94 * | | 95 * | Reference Timestamp (64) | 96 * | | 97 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 98 * | | 99 * | Originate Timestamp (64) | 100 * | | 101 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 102 * | | 103 * | Receive Timestamp (64) | 104 * | | 105 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 106 * | | 107 * | Transmit Timestamp (64) | 108 * | | 109 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 110 * | Key Identifier (optional) (32) | 111 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 112 * | | 113 * | | 114 * | Message Digest (optional) (128) | 115 * | | 116 * | | 117 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 118 */ 119 120 struct ntpdata { 121 u_char status; /* status of local clock and leap info */ 122 u_char stratum; /* Stratum level */ 123 u_char ppoll; /* poll value */ 124 int precision:8; 125 struct s_fixedpt root_delay; 126 struct s_fixedpt root_dispersion; 127 uint32_t refid; 128 struct l_fixedpt ref_timestamp; 129 struct l_fixedpt org_timestamp; 130 struct l_fixedpt rec_timestamp; 131 struct l_fixedpt xmt_timestamp; 132 uint32_t key_id; 133 uint8_t message_digest[16]; 134 }; 135 /* 136 * Leap Second Codes (high order two bits) 137 */ 138 #define NO_WARNING 0x00 /* no warning */ 139 #define PLUS_SEC 0x40 /* add a second (61 seconds) */ 140 #define MINUS_SEC 0x80 /* minus a second (59 seconds) */ 141 #define ALARM 0xc0 /* alarm condition (clock unsynchronized) */ 142 143 /* 144 * Clock Status Bits that Encode Version 145 */ 146 #define NTPVERSION_1 0x08 147 #define VERSIONMASK 0x38 148 #define LEAPMASK 0xc0 149 #ifdef MODEMASK 150 #undef MODEMASK /* Solaris sucks */ 151 #endif 152 #define MODEMASK 0x07 153 154 /* 155 * Code values 156 */ 157 #define MODE_UNSPEC 0 /* unspecified */ 158 #define MODE_SYM_ACT 1 /* symmetric active */ 159 #define MODE_SYM_PAS 2 /* symmetric passive */ 160 #define MODE_CLIENT 3 /* client */ 161 #define MODE_SERVER 4 /* server */ 162 #define MODE_BROADCAST 5 /* broadcast */ 163 #define MODE_RES1 6 /* reserved */ 164 #define MODE_RES2 7 /* reserved */ 165 166 /* 167 * Stratum Definitions 168 */ 169 #define UNSPECIFIED 0 170 #define PRIM_REF 1 /* radio clock */ 171 #define INFO_QUERY 62 /* **** THIS implementation dependent **** */ 172 #define INFO_REPLY 63 /* **** THIS implementation dependent **** */ 173 174 static void p_sfix(netdissect_options *ndo, const struct s_fixedpt *); 175 static void p_ntp_time(netdissect_options *, const struct l_fixedpt *); 176 static void p_ntp_delta(netdissect_options *, const struct l_fixedpt *, const struct l_fixedpt *); 177 178 static const struct tok ntp_mode_values[] = { 179 { MODE_UNSPEC, "unspecified" }, 180 { MODE_SYM_ACT, "symmetric active" }, 181 { MODE_SYM_PAS, "symmetric passive" }, 182 { MODE_CLIENT, "Client" }, 183 { MODE_SERVER, "Server" }, 184 { MODE_BROADCAST, "Broadcast" }, 185 { MODE_RES1, "Reserved" }, 186 { MODE_RES2, "Reserved" }, 187 { 0, NULL } 188 }; 189 190 static const struct tok ntp_leapind_values[] = { 191 { NO_WARNING, "" }, 192 { PLUS_SEC, "+1s" }, 193 { MINUS_SEC, "-1s" }, 194 { ALARM, "clock unsynchronized" }, 195 { 0, NULL } 196 }; 197 198 static const struct tok ntp_stratum_values[] = { 199 { UNSPECIFIED, "unspecified" }, 200 { PRIM_REF, "primary reference" }, 201 { 0, NULL } 202 }; 203 204 /* 205 * Print ntp requests 206 */ 207 void 208 ntp_print(netdissect_options *ndo, 209 register const u_char *cp, u_int length) 210 { 211 register const struct ntpdata *bp; 212 int mode, version, leapind; 213 214 bp = (const struct ntpdata *)cp; 215 216 ND_TCHECK(bp->status); 217 218 version = (int)(bp->status & VERSIONMASK) >> 3; 219 ND_PRINT((ndo, "NTPv%d", version)); 220 221 mode = bp->status & MODEMASK; 222 if (!ndo->ndo_vflag) { 223 ND_PRINT((ndo, ", %s, length %u", 224 tok2str(ntp_mode_values, "Unknown mode", mode), 225 length)); 226 return; 227 } 228 229 ND_PRINT((ndo, ", length %u\n\t%s", 230 length, 231 tok2str(ntp_mode_values, "Unknown mode", mode))); 232 233 leapind = bp->status & LEAPMASK; 234 ND_PRINT((ndo, ", Leap indicator: %s (%u)", 235 tok2str(ntp_leapind_values, "Unknown", leapind), 236 leapind)); 237 238 ND_TCHECK(bp->stratum); 239 ND_PRINT((ndo, ", Stratum %u (%s)", 240 bp->stratum, 241 tok2str(ntp_stratum_values, (bp->stratum >=2 && bp->stratum<=15) ? "secondary reference" : "reserved", bp->stratum))); 242 243 ND_TCHECK(bp->ppoll); 244 ND_PRINT((ndo, ", poll %u (%us)", bp->ppoll, 1 << bp->ppoll)); 245 246 /* Can't ND_TCHECK bp->precision bitfield so bp->distance + 0 instead */ 247 ND_TCHECK2(bp->root_delay, 0); 248 ND_PRINT((ndo, ", precision %d", bp->precision)); 249 250 ND_TCHECK(bp->root_delay); 251 ND_PRINT((ndo, "\n\tRoot Delay: ")); 252 p_sfix(ndo, &bp->root_delay); 253 254 ND_TCHECK(bp->root_dispersion); 255 ND_PRINT((ndo, ", Root dispersion: ")); 256 p_sfix(ndo, &bp->root_dispersion); 257 258 ND_TCHECK(bp->refid); 259 ND_PRINT((ndo, ", Reference-ID: ")); 260 /* Interpretation depends on stratum */ 261 switch (bp->stratum) { 262 263 case UNSPECIFIED: 264 ND_PRINT((ndo, "(unspec)")); 265 break; 266 267 case PRIM_REF: 268 if (fn_printn(ndo, (const u_char *)&(bp->refid), 4, ndo->ndo_snapend)) 269 goto trunc; 270 break; 271 272 case INFO_QUERY: 273 ND_PRINT((ndo, "%s INFO_QUERY", ipaddr_string(ndo, &(bp->refid)))); 274 /* this doesn't have more content */ 275 return; 276 277 case INFO_REPLY: 278 ND_PRINT((ndo, "%s INFO_REPLY", ipaddr_string(ndo, &(bp->refid)))); 279 /* this is too complex to be worth printing */ 280 return; 281 282 default: 283 ND_PRINT((ndo, "%s", ipaddr_string(ndo, &(bp->refid)))); 284 break; 285 } 286 287 ND_TCHECK(bp->ref_timestamp); 288 ND_PRINT((ndo, "\n\t Reference Timestamp: ")); 289 p_ntp_time(ndo, &(bp->ref_timestamp)); 290 291 ND_TCHECK(bp->org_timestamp); 292 ND_PRINT((ndo, "\n\t Originator Timestamp: ")); 293 p_ntp_time(ndo, &(bp->org_timestamp)); 294 295 ND_TCHECK(bp->rec_timestamp); 296 ND_PRINT((ndo, "\n\t Receive Timestamp: ")); 297 p_ntp_time(ndo, &(bp->rec_timestamp)); 298 299 ND_TCHECK(bp->xmt_timestamp); 300 ND_PRINT((ndo, "\n\t Transmit Timestamp: ")); 301 p_ntp_time(ndo, &(bp->xmt_timestamp)); 302 303 ND_PRINT((ndo, "\n\t Originator - Receive Timestamp: ")); 304 p_ntp_delta(ndo, &(bp->org_timestamp), &(bp->rec_timestamp)); 305 306 ND_PRINT((ndo, "\n\t Originator - Transmit Timestamp: ")); 307 p_ntp_delta(ndo, &(bp->org_timestamp), &(bp->xmt_timestamp)); 308 309 if ( (sizeof(struct ntpdata) - length) == 16) { /* Optional: key-id */ 310 ND_TCHECK(bp->key_id); 311 ND_PRINT((ndo, "\n\tKey id: %u", bp->key_id)); 312 } else if ( (sizeof(struct ntpdata) - length) == 0) { /* Optional: key-id + authentication */ 313 ND_TCHECK(bp->key_id); 314 ND_PRINT((ndo, "\n\tKey id: %u", bp->key_id)); 315 ND_TCHECK2(bp->message_digest, sizeof (bp->message_digest)); 316 ND_PRINT((ndo, "\n\tAuthentication: %08x%08x%08x%08x", 317 EXTRACT_32BITS(bp->message_digest), 318 EXTRACT_32BITS(bp->message_digest + 4), 319 EXTRACT_32BITS(bp->message_digest + 8), 320 EXTRACT_32BITS(bp->message_digest + 12))); 321 } 322 return; 323 324 trunc: 325 ND_PRINT((ndo, " [|ntp]")); 326 } 327 328 static void 329 p_sfix(netdissect_options *ndo, 330 register const struct s_fixedpt *sfp) 331 { 332 register int i; 333 register int f; 334 register double ff; 335 336 i = EXTRACT_16BITS(&sfp->int_part); 337 f = EXTRACT_16BITS(&sfp->fraction); 338 ff = f / 65536.0; /* shift radix point by 16 bits */ 339 f = (int)(ff * 1000000.0); /* Treat fraction as parts per million */ 340 ND_PRINT((ndo, "%d.%06d", i, f)); 341 } 342 343 #define FMAXINT (4294967296.0) /* floating point rep. of MAXINT */ 344 345 static void 346 p_ntp_time(netdissect_options *ndo, 347 register const struct l_fixedpt *lfp) 348 { 349 register int32_t i; 350 register uint32_t uf; 351 register uint32_t f; 352 register double ff; 353 354 i = EXTRACT_32BITS(&lfp->int_part); 355 uf = EXTRACT_32BITS(&lfp->fraction); 356 ff = uf; 357 if (ff < 0.0) /* some compilers are buggy */ 358 ff += FMAXINT; 359 ff = ff / FMAXINT; /* shift radix point by 32 bits */ 360 f = (uint32_t)(ff * 1000000000.0); /* treat fraction as parts per billion */ 361 ND_PRINT((ndo, "%u.%09d", i, f)); 362 363 #ifdef HAVE_STRFTIME 364 /* 365 * print the time in human-readable format. 366 */ 367 if (i) { 368 time_t seconds = i - JAN_1970; 369 struct tm *tm; 370 char time_buf[128]; 371 372 tm = localtime(&seconds); 373 strftime(time_buf, sizeof (time_buf), "%Y/%m/%d %H:%M:%S", tm); 374 ND_PRINT((ndo, " (%s)", time_buf)); 375 } 376 #endif 377 } 378 379 /* Prints time difference between *lfp and *olfp */ 380 static void 381 p_ntp_delta(netdissect_options *ndo, 382 register const struct l_fixedpt *olfp, 383 register const struct l_fixedpt *lfp) 384 { 385 register int32_t i; 386 register uint32_t u, uf; 387 register uint32_t ou, ouf; 388 register uint32_t f; 389 register double ff; 390 int signbit; 391 392 u = EXTRACT_32BITS(&lfp->int_part); 393 ou = EXTRACT_32BITS(&olfp->int_part); 394 uf = EXTRACT_32BITS(&lfp->fraction); 395 ouf = EXTRACT_32BITS(&olfp->fraction); 396 if (ou == 0 && ouf == 0) { 397 p_ntp_time(ndo, lfp); 398 return; 399 } 400 401 i = u - ou; 402 403 if (i > 0) { /* new is definitely greater than old */ 404 signbit = 0; 405 f = uf - ouf; 406 if (ouf > uf) /* must borrow from high-order bits */ 407 i -= 1; 408 } else if (i < 0) { /* new is definitely less than old */ 409 signbit = 1; 410 f = ouf - uf; 411 if (uf > ouf) /* must carry into the high-order bits */ 412 i += 1; 413 i = -i; 414 } else { /* int_part is zero */ 415 if (uf > ouf) { 416 signbit = 0; 417 f = uf - ouf; 418 } else { 419 signbit = 1; 420 f = ouf - uf; 421 } 422 } 423 424 ff = f; 425 if (ff < 0.0) /* some compilers are buggy */ 426 ff += FMAXINT; 427 ff = ff / FMAXINT; /* shift radix point by 32 bits */ 428 f = (uint32_t)(ff * 1000000000.0); /* treat fraction as parts per billion */ 429 ND_PRINT((ndo, "%s%d.%09d", signbit ? "-" : "+", i, f)); 430 } 431 432