1 /* $OpenBSD: print-ntp.c,v 1.11 2002/02/19 19:39:40 millert Exp $ */ 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 #ifndef lint 29 static const char rcsid[] = 30 "@(#) $Header: /home/cvs/src/usr.sbin/tcpdump/print-ntp.c,v 1.11 2002/02/19 19:39:40 millert Exp $ (LBL)"; 31 #endif 32 33 #include <sys/param.h> 34 #include <sys/time.h> 35 #include <sys/socket.h> 36 37 struct mbuf; 38 struct rtentry; 39 #include <net/if.h> 40 41 #include <netinet/in.h> 42 #include <netinet/if_ether.h> 43 44 #include <ctype.h> 45 #include <stdio.h> 46 #include <string.h> 47 48 #include "interface.h" 49 #include "addrtoname.h" 50 #ifdef MODEMASK 51 #undef MODEMASK /* Solaris sucks */ 52 #endif 53 #include "ntp.h" 54 55 static void p_sfix(const struct s_fixedpt *); 56 static void p_ntp_time(const struct l_fixedpt *); 57 static void p_ntp_delta(const struct l_fixedpt *, const struct l_fixedpt *); 58 59 /* 60 * Print ntp requests 61 */ 62 void 63 ntp_print(register const u_char *cp, u_int length) 64 { 65 register const struct ntpdata *bp; 66 int mode, version, leapind; 67 static char rclock[5]; 68 69 bp = (struct ntpdata *)cp; 70 /* Note funny sized packets */ 71 if (length != sizeof(struct ntpdata)) 72 (void)printf(" [len=%d]", length); 73 74 TCHECK(bp->status); 75 76 version = (int)(bp->status & VERSIONMASK) >> 3; 77 printf(" v%d", version); 78 79 leapind = bp->status & LEAPMASK; 80 switch (leapind) { 81 82 case NO_WARNING: 83 break; 84 85 case PLUS_SEC: 86 fputs(" +1s", stdout); 87 break; 88 89 case MINUS_SEC: 90 fputs(" -1s", stdout); 91 break; 92 } 93 94 mode = bp->status & MODEMASK; 95 switch (mode) { 96 97 case MODE_UNSPEC: /* unspecified */ 98 fputs(" unspec", stdout); 99 break; 100 101 case MODE_SYM_ACT: /* symmetric active */ 102 fputs(" sym_act", stdout); 103 break; 104 105 case MODE_SYM_PAS: /* symmetric passive */ 106 fputs(" sym_pas", stdout); 107 break; 108 109 case MODE_CLIENT: /* client */ 110 fputs(" client", stdout); 111 break; 112 113 case MODE_SERVER: /* server */ 114 fputs(" server", stdout); 115 break; 116 117 case MODE_BROADCAST: /* broadcast */ 118 fputs(" bcast", stdout); 119 break; 120 121 case MODE_RES1: /* reserved */ 122 fputs(" res1", stdout); 123 break; 124 125 case MODE_RES2: /* reserved */ 126 fputs(" res2", stdout); 127 break; 128 129 } 130 131 TCHECK(bp->stratum); 132 printf(" strat %d", bp->stratum); 133 134 TCHECK(bp->ppoll); 135 printf(" poll %d", bp->ppoll); 136 137 /* Can't TCHECK bp->precision bitfield so bp->distance + 0 instead */ 138 TCHECK2(bp->distance, 0); 139 printf(" prec %d", bp->precision); 140 141 if (!vflag) 142 return; 143 144 TCHECK(bp->distance); 145 fputs(" dist ", stdout); 146 p_sfix(&bp->distance); 147 148 TCHECK(bp->dispersion); 149 fputs(" disp ", stdout); 150 p_sfix(&bp->dispersion); 151 152 TCHECK(bp->refid); 153 fputs(" ref ", stdout); 154 /* Interpretation depends on stratum */ 155 switch (bp->stratum) { 156 157 case UNSPECIFIED: 158 printf("(unspec)"); 159 break; 160 161 case PRIM_REF: 162 strlcpy(rclock, (char *)&(bp->refid), sizeof(rclock)); 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