dist/tcpdump/print-ntp.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that: (1) source code distributions
   9  * retain the above copyright notice and this paragraph in its entirety, (2)
  10  * distributions including binary code include the above copyright notice and
  11  * this paragraph in its entirety in the documentation or other materials
  12  * provided with the distribution, and (3) all advertising materials mentioning
  13  * features or use of this software display the following acknowledgement:
  14  * ``This product includes software developed by the University of California,
  15  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  16  * the University nor the names of its contributors may be used to endorse
  17  * or promote products derived from this software without specific prior
  18  * written permission.
  19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  20  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  22  *
  23  * Format and print ntp packets.
  24  *      By Jeffrey Mogul/DECWRL
  25  *      loosely based on print-bootp.c
  26  */
  27
  28 #include <sys/cdefs.h>
  29 #ifndef lint
  30 #if 0
  31 static const char rcsid[] _U_ =
  32     "@(#) Header: /tcpdump/master/tcpdump/print-ntp.c,v 1.41.2.1 2005/05/06 07:57:18 guy Exp (LBL)";
  33 #else
  34 __RCSID("$NetBSD: tcpdump2rcsid.ex,v 1.1 2001/06/25 20:09:58 itojun Exp $");
  35 #endif
  36 #endif
  37
  38 #ifdef HAVE_CONFIG_H
  39 #include "config.h"
  40 #endif
  41
  42 #include <tcpdump-stdinc.h>
  43
  44 #include <stdio.h>
  45 #include <string.h>
  46 #ifdef HAVE_STRFTIME
  47 #include <time.h>
  48 #endif
  49
  50 #include "interface.h"
  51 #include "addrtoname.h"
  52 #include "extract.h"
  53 #ifdef MODEMASK
  54 #undef MODEMASK                                 /* Solaris sucks */
  55 #endif
  56 #include "ntp.h"
  57
  58 static void p_sfix(const struct s_fixedpt *);
  59 static void p_ntp_time(const struct l_fixedpt *);
  60 static void p_ntp_delta(const struct l_fixedpt *, const struct l_fixedpt *);
  61
  62 static struct tok ntp_mode_values[] = {
  63     { MODE_UNSPEC,    "unspecified" },
  64     { MODE_SYM_ACT,   "symmetric active" },
  65     { MODE_SYM_PAS,   "symmetric passive" },
  66     { MODE_CLIENT,    "Client" },
  67     { MODE_SERVER,    "Server" },
  68     { MODE_BROADCAST, "Broadcast" },
  69     { MODE_RES1,      "Reserved" },
  70     { MODE_RES2,      "Reserved" },
  71     { 0, NULL }
  72 };
  73
  74 static struct tok ntp_leapind_values[] = {
  75     { NO_WARNING,     "" },
  76     { PLUS_SEC,       "+1s" },
  77     { MINUS_SEC,      "-1s" },
  78     { ALARM,          "clock unsynchronized" },
  79     { 0, NULL }
  80 };
  81
  82 /*
  83  * Print ntp requests
  84  */
  85 void
  86 ntp_print(register const u_char *cp, u_int length)
  87 {
  88         register const struct ntpdata *bp;
  89         int mode, version, leapind;
  90
  91         bp = (struct ntpdata *)cp;
  92
  93         TCHECK(bp->status);
  94
  95         version = (int)(bp->status & VERSIONMASK) >> 3;
  96         printf("NTPv%d", version);
  97
  98         mode = bp->status & MODEMASK;
  99         if (!vflag) {
 100             printf (", %s, length %u",
 101                     tok2str(ntp_mode_values, "Unknown mode", mode),
 102                     length);
 103             return;
 104         }
 105
 106         printf (", length %u\n\t%s",
 107                 length,
 108                 tok2str(ntp_mode_values, "Unknown mode", mode));
 109
 110         leapind = bp->status & LEAPMASK;
 111         printf (", Leap indicator: %s (%u)",
 112                 tok2str(ntp_leapind_values, "Unknown", leapind),
 113                 leapind);
 114
 115         TCHECK(bp->stratum);
 116         printf(", Stratum %u", bp->stratum);
 117
 118         TCHECK(bp->ppoll);
 119         printf(", poll %us", bp->ppoll);
 120
 121         /* Can't TCHECK bp->precision bitfield so bp->distance + 0 instead */
 122         TCHECK2(bp->root_delay, 0);
 123         printf(", precision %d", bp->precision);
 124
 125         TCHECK(bp->root_delay);
 126         fputs("\n\tRoot Delay: ", stdout);
 127         p_sfix(&bp->root_delay);
 128
 129         TCHECK(bp->root_dispersion);
 130         fputs(", Root dispersion: ", stdout);
 131         p_sfix(&bp->root_dispersion);
 132
 133         TCHECK(bp->refid);
 134         fputs(", Reference-ID: ", stdout);
 135         /* Interpretation depends on stratum */
 136         switch (bp->stratum) {
 137
 138         case UNSPECIFIED:
 139                 printf("(unspec)");
 140                 break;
 141
 142         case PRIM_REF:
 143                 if (fn_printn((u_char *)&(bp->refid), 4, snapend))
 144                         goto trunc;
 145                 break;
 146
 147         case INFO_QUERY:
 148                 printf("%s INFO_QUERY", ipaddr_string(&(bp->refid)));
 149                 /* this doesn't have more content */
 150                 return;
 151
 152         case INFO_REPLY:
 153                 printf("%s INFO_REPLY", ipaddr_string(&(bp->refid)));
 154                 /* this is too complex to be worth printing */
 155                 return;
 156
 157         default:
 158                 printf("%s", ipaddr_string(&(bp->refid)));
 159                 break;
 160         }
 161
 162         TCHECK(bp->ref_timestamp);
 163         fputs("\n\t  Reference Timestamp:  ", stdout);
 164         p_ntp_time(&(bp->ref_timestamp));
 165
 166         TCHECK(bp->org_timestamp);
 167         fputs("\n\t  Originator Timestamp: ", stdout);
 168         p_ntp_time(&(bp->org_timestamp));
 169
 170         TCHECK(bp->rec_timestamp);
 171         fputs("\n\t  Receive Timestamp:    ", stdout);
 172         p_ntp_time(&(bp->rec_timestamp));
 173
 174         TCHECK(bp->xmt_timestamp);
 175         fputs("\n\t  Transmit Timestamp:   ", stdout);
 176         p_ntp_time(&(bp->xmt_timestamp));
 177
 178         fputs("\n\t    Originator - Receive Timestamp:  ", stdout);
 179         p_ntp_delta(&(bp->org_timestamp), &(bp->rec_timestamp));
 180
 181         fputs("\n\t    Originator - Transmit Timestamp: ", stdout);
 182         p_ntp_delta(&(bp->org_timestamp), &(bp->xmt_timestamp));
 183
 184         /* FIXME key-id, authentication */
 185
 186         return;
 187
 188 trunc:
 189         fputs(" [|ntp]", stdout);
 190 }
 191
 192 static void
 193 p_sfix(register const struct s_fixedpt *sfp)
 194 {
 195         register int i;
 196         register int f;
 197         register float ff;
 198
 199         i = EXTRACT_16BITS(&sfp->int_part);
 200         f = EXTRACT_16BITS(&sfp->fraction);
 201         ff = f / 65536.0;       /* shift radix point by 16 bits */
 202         f = ff * 1000000.0;     /* Treat fraction as parts per million */
 203         printf("%d.%06d", i, f);
 204 }
 205
 206 #define FMAXINT (4294967296.0)  /* floating point rep. of MAXINT */
 207
 208 static void
 209 p_ntp_time(register const struct l_fixedpt *lfp)
 210 {
 211         register int32_t i;
 212         register u_int32_t uf;
 213         register u_int32_t f;
 214         register float ff;
 215
 216         i = EXTRACT_32BITS(&lfp->int_part);
 217         uf = EXTRACT_32BITS(&lfp->fraction);
 218         ff = uf;
 219         if (ff < 0.0)           /* some compilers are buggy */
 220                 ff += FMAXINT;
 221         ff = ff / FMAXINT;      /* shift radix point by 32 bits */
 222         f = ff * 1000000000.0;  /* treat fraction as parts per billion */
 223         printf("%u.%09d", i, f);
 224
 225 #ifdef HAVE_STRFTIME
 226         /*
 227          * print the time in human-readable format.
 228          */
 229         if (i) {
 230             time_t seconds = i - JAN_1970;
 231             struct tm *tm;
 232             char time_buf[128];
 233
 234             tm = localtime(&seconds);
 235             strftime(time_buf, sizeof (time_buf), "%Y/%m/%d %H:%M:%S", tm);
 236             printf (" (%s)", time_buf);
 237         }
 238 #endif
 239 }
 240
 241 /* Prints time difference between *lfp and *olfp */
 242 static void
 243 p_ntp_delta(register const struct l_fixedpt *olfp,
 244             register const struct l_fixedpt *lfp)
 245 {
 246         register int32_t i;
 247         register u_int32_t u, uf;
 248         register u_int32_t ou, ouf;
 249         register u_int32_t f;
 250         register float ff;
 251         int signbit;
 252
 253         u = EXTRACT_32BITS(&lfp->int_part);
 254         ou = EXTRACT_32BITS(&olfp->int_part);
 255         uf = EXTRACT_32BITS(&lfp->fraction);
 256         ouf = EXTRACT_32BITS(&olfp->fraction);
 257         if (ou == 0 && ouf == 0) {
 258                 p_ntp_time(lfp);
 259                 return;
 260         }
 261
 262         i = u - ou;
 263
 264         if (i > 0) {            /* new is definitely greater than old */
 265                 signbit = 0;
 266                 f = uf - ouf;
 267                 if (ouf > uf)   /* must borrow from high-order bits */
 268                         i -= 1;
 269         } else if (i < 0) {     /* new is definitely less than old */
 270                 signbit = 1;
 271                 f = ouf - uf;
 272                 if (uf > ouf)   /* must carry into the high-order bits */
 273                         i += 1;
 274                 i = -i;
 275         } else {                /* int_part is zero */
 276                 if (uf > ouf) {
 277                         signbit = 0;
 278                         f = uf - ouf;
 279                 } else {
 280                         signbit = 1;
 281                         f = ouf - uf;
 282                 }
 283         }
 284
 285         ff = f;
 286         if (ff < 0.0)           /* some compilers are buggy */
 287                 ff += FMAXINT;
 288         ff = ff / FMAXINT;      /* shift radix point by 32 bits */
 289         f = ff * 1000000000.0;  /* treat fraction as parts per billion */
 290         if (signbit)
 291                 putchar('-');
 292         else
 293                 putchar('+');
 294         printf("%d.%09d", i, f);
 295 }
 296