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 #if 0 29 static const char rcsid[] _U_ = 30 "@(#) Header: /tcpdump/master/tcpdump/print-ntp.c,v 1.43 2007-11-30 13:45:10 hannes Exp (LBL)"; 31 #else 32 __RCSID("$NetBSD: print-ntp.c,v 1.2 2010/12/05 05:11:30 christos Exp $"); 33 #endif 34 #endif 35 36 #ifdef HAVE_CONFIG_H 37 #include "config.h" 38 #endif 39 40 #include <tcpdump-stdinc.h> 41 42 #include <stdio.h> 43 #include <string.h> 44 #ifdef HAVE_STRFTIME 45 #include <time.h> 46 #endif 47 48 #include "interface.h" 49 #include "addrtoname.h" 50 #include "extract.h" 51 #ifdef MODEMASK 52 #undef MODEMASK /* Solaris sucks */ 53 #endif 54 #include "ntp.h" 55 56 static void p_sfix(const struct s_fixedpt *); 57 static void p_ntp_time(const struct l_fixedpt *); 58 static void p_ntp_delta(const struct l_fixedpt *, const struct l_fixedpt *); 59 60 static struct tok ntp_mode_values[] = { 61 { MODE_UNSPEC, "unspecified" }, 62 { MODE_SYM_ACT, "symmetric active" }, 63 { MODE_SYM_PAS, "symmetric passive" }, 64 { MODE_CLIENT, "Client" }, 65 { MODE_SERVER, "Server" }, 66 { MODE_BROADCAST, "Broadcast" }, 67 { MODE_RES1, "Reserved" }, 68 { MODE_RES2, "Reserved" }, 69 { 0, NULL } 70 }; 71 72 static struct tok ntp_leapind_values[] = { 73 { NO_WARNING, "" }, 74 { PLUS_SEC, "+1s" }, 75 { MINUS_SEC, "-1s" }, 76 { ALARM, "clock unsynchronized" }, 77 { 0, NULL } 78 }; 79 80 static struct tok ntp_stratum_values[] = { 81 { UNSPECIFIED, "unspecified" }, 82 { PRIM_REF, "primary reference" }, 83 { 0, NULL } 84 }; 85 86 /* 87 * Print ntp requests 88 */ 89 void 90 ntp_print(register const u_char *cp, u_int length) 91 { 92 register const struct ntpdata *bp; 93 int mode, version, leapind; 94 95 bp = (struct ntpdata *)cp; 96 97 TCHECK(bp->status); 98 99 version = (int)(bp->status & VERSIONMASK) >> 3; 100 printf("NTPv%d", version); 101 102 mode = bp->status & MODEMASK; 103 if (!vflag) { 104 printf (", %s, length %u", 105 tok2str(ntp_mode_values, "Unknown mode", mode), 106 length); 107 return; 108 } 109 110 printf (", length %u\n\t%s", 111 length, 112 tok2str(ntp_mode_values, "Unknown mode", mode)); 113 114 leapind = bp->status & LEAPMASK; 115 printf (", Leap indicator: %s (%u)", 116 tok2str(ntp_leapind_values, "Unknown", leapind), 117 leapind); 118 119 TCHECK(bp->stratum); 120 printf(", Stratum %u (%s)", 121 bp->stratum, 122 tok2str(ntp_stratum_values, (bp->stratum >=2 && bp->stratum<=15) ? "secondary reference" : "reserved", bp->stratum)); 123 124 TCHECK(bp->ppoll); 125 printf(", poll %us", bp->ppoll); 126 127 /* Can't TCHECK bp->precision bitfield so bp->distance + 0 instead */ 128 TCHECK2(bp->root_delay, 0); 129 printf(", precision %d", bp->precision); 130 131 TCHECK(bp->root_delay); 132 fputs("\n\tRoot Delay: ", stdout); 133 p_sfix(&bp->root_delay); 134 135 TCHECK(bp->root_dispersion); 136 fputs(", Root dispersion: ", stdout); 137 p_sfix(&bp->root_dispersion); 138 139 TCHECK(bp->refid); 140 fputs(", Reference-ID: ", stdout); 141 /* Interpretation depends on stratum */ 142 switch (bp->stratum) { 143 144 case UNSPECIFIED: 145 printf("(unspec)"); 146 break; 147 148 case PRIM_REF: 149 if (fn_printn((u_char *)&(bp->refid), 4, snapend)) 150 goto trunc; 151 break; 152 153 case INFO_QUERY: 154 printf("%s INFO_QUERY", ipaddr_string(&(bp->refid))); 155 /* this doesn't have more content */ 156 return; 157 158 case INFO_REPLY: 159 printf("%s INFO_REPLY", ipaddr_string(&(bp->refid))); 160 /* this is too complex to be worth printing */ 161 return; 162 163 default: 164 printf("%s", ipaddr_string(&(bp->refid))); 165 break; 166 } 167 168 TCHECK(bp->ref_timestamp); 169 fputs("\n\t Reference Timestamp: ", stdout); 170 p_ntp_time(&(bp->ref_timestamp)); 171 172 TCHECK(bp->org_timestamp); 173 fputs("\n\t Originator Timestamp: ", stdout); 174 p_ntp_time(&(bp->org_timestamp)); 175 176 TCHECK(bp->rec_timestamp); 177 fputs("\n\t Receive Timestamp: ", stdout); 178 p_ntp_time(&(bp->rec_timestamp)); 179 180 TCHECK(bp->xmt_timestamp); 181 fputs("\n\t Transmit Timestamp: ", stdout); 182 p_ntp_time(&(bp->xmt_timestamp)); 183 184 fputs("\n\t Originator - Receive Timestamp: ", stdout); 185 p_ntp_delta(&(bp->org_timestamp), &(bp->rec_timestamp)); 186 187 fputs("\n\t Originator - Transmit Timestamp: ", stdout); 188 p_ntp_delta(&(bp->org_timestamp), &(bp->xmt_timestamp)); 189 190 if ( (sizeof(struct ntpdata) - length) == 16) { /* Optional: key-id */ 191 TCHECK(bp->key_id); 192 printf("\n\tKey id: %u", bp->key_id); 193 } else if ( (sizeof(struct ntpdata) - length) == 0) { /* Optional: key-id + authentication */ 194 TCHECK(bp->key_id); 195 printf("\n\tKey id: %u", bp->key_id); 196 TCHECK2(bp->message_digest, sizeof (bp->message_digest)); 197 printf("\n\tAuthentication: %08x%08x%08x%08x", 198 EXTRACT_32BITS(bp->message_digest), 199 EXTRACT_32BITS(bp->message_digest + 4), 200 EXTRACT_32BITS(bp->message_digest + 8), 201 EXTRACT_32BITS(bp->message_digest + 12)); 202 } 203 return; 204 205 trunc: 206 fputs(" [|ntp]", stdout); 207 } 208 209 static void 210 p_sfix(register const struct s_fixedpt *sfp) 211 { 212 register int i; 213 register int f; 214 register float ff; 215 216 i = EXTRACT_16BITS(&sfp->int_part); 217 f = EXTRACT_16BITS(&sfp->fraction); 218 ff = f / 65536.0; /* shift radix point by 16 bits */ 219 f = ff * 1000000.0; /* Treat fraction as parts per million */ 220 printf("%d.%06d", i, f); 221 } 222 223 #define FMAXINT (4294967296.0) /* floating point rep. of MAXINT */ 224 225 static void 226 p_ntp_time(register const struct l_fixedpt *lfp) 227 { 228 register int32_t i; 229 register u_int32_t uf; 230 register u_int32_t f; 231 register float ff; 232 233 i = EXTRACT_32BITS(&lfp->int_part); 234 uf = EXTRACT_32BITS(&lfp->fraction); 235 ff = uf; 236 if (ff < 0.0) /* some compilers are buggy */ 237 ff += FMAXINT; 238 ff = ff / FMAXINT; /* shift radix point by 32 bits */ 239 f = ff * 1000000000.0; /* treat fraction as parts per billion */ 240 printf("%u.%09d", i, f); 241 242 #ifdef HAVE_STRFTIME 243 /* 244 * print the time in human-readable format. 245 */ 246 if (i) { 247 time_t seconds = i - JAN_1970; 248 struct tm *tm; 249 char time_buf[128]; 250 251 tm = localtime(&seconds); 252 strftime(time_buf, sizeof (time_buf), "%Y/%m/%d %H:%M:%S", tm); 253 printf (" (%s)", time_buf); 254 } 255 #endif 256 } 257 258 /* Prints time difference between *lfp and *olfp */ 259 static void 260 p_ntp_delta(register const struct l_fixedpt *olfp, 261 register const struct l_fixedpt *lfp) 262 { 263 register int32_t i; 264 register u_int32_t u, uf; 265 register u_int32_t ou, ouf; 266 register u_int32_t f; 267 register float ff; 268 int signbit; 269 270 u = EXTRACT_32BITS(&lfp->int_part); 271 ou = EXTRACT_32BITS(&olfp->int_part); 272 uf = EXTRACT_32BITS(&lfp->fraction); 273 ouf = EXTRACT_32BITS(&olfp->fraction); 274 if (ou == 0 && ouf == 0) { 275 p_ntp_time(lfp); 276 return; 277 } 278 279 i = u - ou; 280 281 if (i > 0) { /* new is definitely greater than old */ 282 signbit = 0; 283 f = uf - ouf; 284 if (ouf > uf) /* must borrow from high-order bits */ 285 i -= 1; 286 } else if (i < 0) { /* new is definitely less than old */ 287 signbit = 1; 288 f = ouf - uf; 289 if (uf > ouf) /* must carry into the high-order bits */ 290 i += 1; 291 i = -i; 292 } else { /* int_part is zero */ 293 if (uf > ouf) { 294 signbit = 0; 295 f = uf - ouf; 296 } else { 297 signbit = 1; 298 f = ouf - uf; 299 } 300 } 301 302 ff = f; 303 if (ff < 0.0) /* some compilers are buggy */ 304 ff += FMAXINT; 305 ff = ff / FMAXINT; /* shift radix point by 32 bits */ 306 f = ff * 1000000000.0; /* treat fraction as parts per billion */ 307 if (signbit) 308 putchar('-'); 309 else 310 putchar('+'); 311 printf("%d.%09d", i, f); 312 } 313 314