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 #ifndef lint 27 static const char rcsid[] _U_ = 28 "@(#) $Header: /tcpdump/master/tcpdump/print-ntp.c,v 1.42 2005-05-06 07:56:53 guy Exp $ (LBL)"; 29 #endif 30 31 #ifdef HAVE_CONFIG_H 32 #include "config.h" 33 #endif 34 35 #include <tcpdump-stdinc.h> 36 37 #include <stdio.h> 38 #include <string.h> 39 #ifdef HAVE_STRFTIME 40 #include <time.h> 41 #endif 42 43 #include "interface.h" 44 #include "addrtoname.h" 45 #include "extract.h" 46 #ifdef MODEMASK 47 #undef MODEMASK /* Solaris sucks */ 48 #endif 49 #include "ntp.h" 50 51 static void p_sfix(const struct s_fixedpt *); 52 static void p_ntp_time(const struct l_fixedpt *); 53 static void p_ntp_delta(const struct l_fixedpt *, const struct l_fixedpt *); 54 55 static struct tok ntp_mode_values[] = { 56 { MODE_UNSPEC, "unspecified" }, 57 { MODE_SYM_ACT, "symmetric active" }, 58 { MODE_SYM_PAS, "symmetric passive" }, 59 { MODE_CLIENT, "Client" }, 60 { MODE_SERVER, "Server" }, 61 { MODE_BROADCAST, "Broadcast" }, 62 { MODE_RES1, "Reserved" }, 63 { MODE_RES2, "Reserved" }, 64 { 0, NULL } 65 }; 66 67 static struct tok ntp_leapind_values[] = { 68 { NO_WARNING, "" }, 69 { PLUS_SEC, "+1s" }, 70 { MINUS_SEC, "-1s" }, 71 { ALARM, "clock unsynchronized" }, 72 { 0, NULL } 73 }; 74 75 /* 76 * Print ntp requests 77 */ 78 void 79 ntp_print(register const u_char *cp, u_int length) 80 { 81 register const struct ntpdata *bp; 82 int mode, version, leapind; 83 84 bp = (struct ntpdata *)cp; 85 86 TCHECK(bp->status); 87 88 version = (int)(bp->status & VERSIONMASK) >> 3; 89 printf("NTPv%d", version); 90 91 mode = bp->status & MODEMASK; 92 if (!vflag) { 93 printf (", %s, length %u", 94 tok2str(ntp_mode_values, "Unknown mode", mode), 95 length); 96 return; 97 } 98 99 printf (", length %u\n\t%s", 100 length, 101 tok2str(ntp_mode_values, "Unknown mode", mode)); 102 103 leapind = bp->status & LEAPMASK; 104 printf (", Leap indicator: %s (%u)", 105 tok2str(ntp_leapind_values, "Unknown", leapind), 106 leapind); 107 108 TCHECK(bp->stratum); 109 printf(", Stratum %u", bp->stratum); 110 111 TCHECK(bp->ppoll); 112 printf(", poll %us", bp->ppoll); 113 114 /* Can't TCHECK bp->precision bitfield so bp->distance + 0 instead */ 115 TCHECK2(bp->root_delay, 0); 116 printf(", precision %d", bp->precision); 117 118 TCHECK(bp->root_delay); 119 fputs("\n\tRoot Delay: ", stdout); 120 p_sfix(&bp->root_delay); 121 122 TCHECK(bp->root_dispersion); 123 fputs(", Root dispersion: ", stdout); 124 p_sfix(&bp->root_dispersion); 125 126 TCHECK(bp->refid); 127 fputs(", Reference-ID: ", stdout); 128 /* Interpretation depends on stratum */ 129 switch (bp->stratum) { 130 131 case UNSPECIFIED: 132 printf("(unspec)"); 133 break; 134 135 case PRIM_REF: 136 if (fn_printn((u_char *)&(bp->refid), 4, snapend)) 137 goto trunc; 138 break; 139 140 case INFO_QUERY: 141 printf("%s INFO_QUERY", ipaddr_string(&(bp->refid))); 142 /* this doesn't have more content */ 143 return; 144 145 case INFO_REPLY: 146 printf("%s INFO_REPLY", ipaddr_string(&(bp->refid))); 147 /* this is too complex to be worth printing */ 148 return; 149 150 default: 151 printf("%s", ipaddr_string(&(bp->refid))); 152 break; 153 } 154 155 TCHECK(bp->ref_timestamp); 156 fputs("\n\t Reference Timestamp: ", stdout); 157 p_ntp_time(&(bp->ref_timestamp)); 158 159 TCHECK(bp->org_timestamp); 160 fputs("\n\t Originator Timestamp: ", stdout); 161 p_ntp_time(&(bp->org_timestamp)); 162 163 TCHECK(bp->rec_timestamp); 164 fputs("\n\t Receive Timestamp: ", stdout); 165 p_ntp_time(&(bp->rec_timestamp)); 166 167 TCHECK(bp->xmt_timestamp); 168 fputs("\n\t Transmit Timestamp: ", stdout); 169 p_ntp_time(&(bp->xmt_timestamp)); 170 171 fputs("\n\t Originator - Receive Timestamp: ", stdout); 172 p_ntp_delta(&(bp->org_timestamp), &(bp->rec_timestamp)); 173 174 fputs("\n\t Originator - Transmit Timestamp: ", stdout); 175 p_ntp_delta(&(bp->org_timestamp), &(bp->xmt_timestamp)); 176 177 /* FIXME key-id, authentication */ 178 179 return; 180 181 trunc: 182 fputs(" [|ntp]", stdout); 183 } 184 185 static void 186 p_sfix(register const struct s_fixedpt *sfp) 187 { 188 register int i; 189 register int f; 190 register float ff; 191 192 i = EXTRACT_16BITS(&sfp->int_part); 193 f = EXTRACT_16BITS(&sfp->fraction); 194 ff = f / 65536.0; /* shift radix point by 16 bits */ 195 f = ff * 1000000.0; /* Treat fraction as parts per million */ 196 printf("%d.%06d", i, f); 197 } 198 199 #define FMAXINT (4294967296.0) /* floating point rep. of MAXINT */ 200 201 static void 202 p_ntp_time(register const struct l_fixedpt *lfp) 203 { 204 register int32_t i; 205 register u_int32_t uf; 206 register u_int32_t f; 207 register float ff; 208 209 i = EXTRACT_32BITS(&lfp->int_part); 210 uf = EXTRACT_32BITS(&lfp->fraction); 211 ff = uf; 212 if (ff < 0.0) /* some compilers are buggy */ 213 ff += FMAXINT; 214 ff = ff / FMAXINT; /* shift radix point by 32 bits */ 215 f = ff * 1000000000.0; /* treat fraction as parts per billion */ 216 printf("%u.%09d", i, f); 217 218 #ifdef HAVE_STRFTIME 219 /* 220 * print the time in human-readable format. 221 */ 222 if (i) { 223 time_t seconds = i - JAN_1970; 224 struct tm *tm; 225 char time_buf[128]; 226 227 tm = localtime(&seconds); 228 strftime(time_buf, sizeof (time_buf), "%Y/%m/%d %H:%M:%S", tm); 229 printf (" (%s)", time_buf); 230 } 231 #endif 232 } 233 234 /* Prints time difference between *lfp and *olfp */ 235 static void 236 p_ntp_delta(register const struct l_fixedpt *olfp, 237 register const struct l_fixedpt *lfp) 238 { 239 register int32_t i; 240 register u_int32_t u, uf; 241 register u_int32_t ou, ouf; 242 register u_int32_t f; 243 register float ff; 244 int signbit; 245 246 u = EXTRACT_32BITS(&lfp->int_part); 247 ou = EXTRACT_32BITS(&olfp->int_part); 248 uf = EXTRACT_32BITS(&lfp->fraction); 249 ouf = EXTRACT_32BITS(&olfp->fraction); 250 if (ou == 0 && ouf == 0) { 251 p_ntp_time(lfp); 252 return; 253 } 254 255 i = u - ou; 256 257 if (i > 0) { /* new is definitely greater than old */ 258 signbit = 0; 259 f = uf - ouf; 260 if (ouf > uf) /* must borrow from high-order bits */ 261 i -= 1; 262 } else if (i < 0) { /* new is definitely less than old */ 263 signbit = 1; 264 f = ouf - uf; 265 if (uf > ouf) /* must carry into the high-order bits */ 266 i += 1; 267 i = -i; 268 } else { /* int_part is zero */ 269 if (uf > ouf) { 270 signbit = 0; 271 f = uf - ouf; 272 } else { 273 signbit = 1; 274 f = ouf - uf; 275 } 276 } 277 278 ff = f; 279 if (ff < 0.0) /* some compilers are buggy */ 280 ff += FMAXINT; 281 ff = ff / FMAXINT; /* shift radix point by 32 bits */ 282 f = ff * 1000000000.0; /* treat fraction as parts per billion */ 283 if (signbit) 284 putchar('-'); 285 else 286 putchar('+'); 287 printf("%d.%09d", i, f); 288 } 289 290