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 * $FreeBSD$ 26 */ 27 28 #ifndef lint 29 static const char rcsid[] = 30 "@(#) $Header: /tcpdump/master/tcpdump/print-ntp.c,v 1.31 2000/10/06 04:23:13 guy Exp $ (LBL)"; 31 #endif 32 33 #ifdef HAVE_CONFIG_H 34 #include "config.h" 35 #endif 36 37 #include <sys/param.h> 38 #include <sys/time.h> 39 #include <sys/socket.h> 40 41 #include <netinet/in.h> 42 43 #include <ctype.h> 44 #include <stdio.h> 45 #include <string.h> 46 47 #include "interface.h" 48 #include "addrtoname.h" 49 #ifdef MODEMASK 50 #undef MODEMASK /* Solaris sucks */ 51 #endif 52 #include "ntp.h" 53 54 static void p_sfix(const struct s_fixedpt *); 55 static void p_ntp_time(const struct l_fixedpt *); 56 static void p_ntp_delta(const struct l_fixedpt *, const struct l_fixedpt *); 57 58 /* 59 * Print ntp requests 60 */ 61 void 62 ntp_print(register const u_char *cp, u_int length) 63 { 64 register const struct ntpdata *bp; 65 int mode, version, leapind; 66 static char rclock[5]; 67 68 bp = (struct ntpdata *)cp; 69 /* Note funny sized packets */ 70 if (length != sizeof(struct ntpdata)) 71 (void)printf(" [len=%d]", length); 72 73 TCHECK(bp->status); 74 75 version = (int)(bp->status & VERSIONMASK) >> 3; 76 printf(" v%d", version); 77 78 leapind = bp->status & LEAPMASK; 79 switch (leapind) { 80 81 case NO_WARNING: 82 break; 83 84 case PLUS_SEC: 85 fputs(" +1s", stdout); 86 break; 87 88 case MINUS_SEC: 89 fputs(" -1s", stdout); 90 break; 91 } 92 93 mode = bp->status & MODEMASK; 94 switch (mode) { 95 96 case MODE_UNSPEC: /* unspecified */ 97 fputs(" unspec", stdout); 98 break; 99 100 case MODE_SYM_ACT: /* symmetric active */ 101 fputs(" sym_act", stdout); 102 break; 103 104 case MODE_SYM_PAS: /* symmetric passive */ 105 fputs(" sym_pas", stdout); 106 break; 107 108 case MODE_CLIENT: /* client */ 109 fputs(" client", stdout); 110 break; 111 112 case MODE_SERVER: /* server */ 113 fputs(" server", stdout); 114 break; 115 116 case MODE_BROADCAST: /* broadcast */ 117 fputs(" bcast", stdout); 118 break; 119 120 case MODE_RES1: /* reserved */ 121 fputs(" res1", stdout); 122 break; 123 124 case MODE_RES2: /* reserved */ 125 fputs(" res2", stdout); 126 break; 127 128 } 129 130 TCHECK(bp->stratum); 131 printf(" strat %d", bp->stratum); 132 133 TCHECK(bp->ppoll); 134 printf(" poll %d", bp->ppoll); 135 136 /* Can't TCHECK bp->precision bitfield so bp->distance + 0 instead */ 137 TCHECK2(bp->distance, 0); 138 printf(" prec %d", bp->precision); 139 140 if (!vflag) 141 return; 142 143 TCHECK(bp->distance); 144 fputs(" dist ", stdout); 145 p_sfix(&bp->distance); 146 147 TCHECK(bp->dispersion); 148 fputs(" disp ", stdout); 149 p_sfix(&bp->dispersion); 150 151 TCHECK(bp->refid); 152 fputs(" ref ", stdout); 153 /* Interpretation depends on stratum */ 154 switch (bp->stratum) { 155 156 case UNSPECIFIED: 157 printf("(unspec)"); 158 break; 159 160 case PRIM_REF: 161 strncpy(rclock, (char *)&(bp->refid), 4); 162 rclock[4] = '\0'; 163 fputs(rclock, stdout); 164 break; 165 166 case INFO_QUERY: 167 printf("%s INFO_QUERY", ipaddr_string(&(bp->refid))); 168 /* this doesn't have more content */ 169 return; 170 171 case INFO_REPLY: 172 printf("%s INFO_REPLY", ipaddr_string(&(bp->refid))); 173 /* this is too complex to be worth printing */ 174 return; 175 176 default: 177 printf("%s", ipaddr_string(&(bp->refid))); 178 break; 179 } 180 181 TCHECK(bp->reftime); 182 putchar('@'); 183 p_ntp_time(&(bp->reftime)); 184 185 TCHECK(bp->org); 186 fputs(" orig ", stdout); 187 p_ntp_time(&(bp->org)); 188 189 TCHECK(bp->rec); 190 fputs(" rec ", stdout); 191 p_ntp_delta(&(bp->org), &(bp->rec)); 192 193 TCHECK(bp->xmt); 194 fputs(" xmt ", stdout); 195 p_ntp_delta(&(bp->org), &(bp->xmt)); 196 197 return; 198 199 trunc: 200 fputs(" [|ntp]", stdout); 201 } 202 203 static void 204 p_sfix(register const struct s_fixedpt *sfp) 205 { 206 register int i; 207 register int f; 208 register float ff; 209 210 i = ntohs(sfp->int_part); 211 f = ntohs(sfp->fraction); 212 ff = f / 65536.0; /* shift radix point by 16 bits */ 213 f = ff * 1000000.0; /* Treat fraction as parts per million */ 214 printf("%d.%06d", i, f); 215 } 216 217 #define FMAXINT (4294967296.0) /* floating point rep. of MAXINT */ 218 219 static void 220 p_ntp_time(register const struct l_fixedpt *lfp) 221 { 222 register int32_t i; 223 register u_int32_t uf; 224 register u_int32_t f; 225 register float ff; 226 227 i = ntohl(lfp->int_part); 228 uf = ntohl(lfp->fraction); 229 ff = uf; 230 if (ff < 0.0) /* some compilers are buggy */ 231 ff += FMAXINT; 232 ff = ff / FMAXINT; /* shift radix point by 32 bits */ 233 f = ff * 1000000000.0; /* treat fraction as parts per billion */ 234 printf("%u.%09d", i, f); 235 } 236 237 /* Prints time difference between *lfp and *olfp */ 238 static void 239 p_ntp_delta(register const struct l_fixedpt *olfp, 240 register const struct l_fixedpt *lfp) 241 { 242 register int32_t i; 243 register u_int32_t uf; 244 register u_int32_t ouf; 245 register u_int32_t f; 246 register float ff; 247 int signbit; 248 249 i = ntohl(lfp->int_part) - ntohl(olfp->int_part); 250 251 uf = ntohl(lfp->fraction); 252 ouf = ntohl(olfp->fraction); 253 254 if (i > 0) { /* new is definitely greater than old */ 255 signbit = 0; 256 f = uf - ouf; 257 if (ouf > uf) /* must borrow from high-order bits */ 258 i -= 1; 259 } else if (i < 0) { /* new is definitely less than old */ 260 signbit = 1; 261 f = ouf - uf; 262 if (uf > ouf) /* must carry into the high-order bits */ 263 i += 1; 264 i = -i; 265 } else { /* int_part is zero */ 266 if (uf > ouf) { 267 signbit = 0; 268 f = uf - ouf; 269 } else { 270 signbit = 1; 271 f = ouf - uf; 272 } 273 } 274 275 ff = f; 276 if (ff < 0.0) /* some compilers are buggy */ 277 ff += FMAXINT; 278 ff = ff / FMAXINT; /* shift radix point by 32 bits */ 279 f = ff * 1000000000.0; /* treat fraction as parts per billion */ 280 if (signbit) 281 putchar('-'); 282 else 283 putchar('+'); 284 printf("%d.%09d", i, f); 285 } 286