1 /* $OpenBSD: print-ntp.c,v 1.20 2021/12/01 18:28:46 deraadt 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 #include <sys/time.h> 29 #include <sys/socket.h> 30 31 #include <net/if.h> 32 33 #include <netinet/in.h> 34 #include <netinet/if_ether.h> 35 36 #include <ctype.h> 37 #include <stdio.h> 38 #include <string.h> 39 40 #include "interface.h" 41 #include "addrtoname.h" 42 #ifdef MODEMASK 43 #undef MODEMASK /* Solaris sucks */ 44 #endif 45 #include "ntp.h" 46 47 static void p_sfix(const struct s_fixedpt *); 48 static void p_ntp_time(const struct l_fixedpt *); 49 static void p_ntp_delta(const struct l_fixedpt *, const struct l_fixedpt *); 50 51 /* 52 * Print ntp requests 53 */ 54 void 55 ntp_print(const u_char *cp, u_int length) 56 { 57 const struct ntpdata *bp; 58 int mode, version, leapind; 59 60 bp = (struct ntpdata *)cp; 61 /* Note funny sized packets */ 62 if (length != sizeof(struct ntpdata)) 63 printf(" [len=%d]", length); 64 65 TCHECK(bp->status); 66 67 version = (int)(bp->status & VERSIONMASK) >> 3; 68 printf("v%d", version); 69 70 leapind = bp->status & LEAPMASK; 71 switch (leapind) { 72 73 case NO_WARNING: 74 break; 75 76 case ALARM: 77 printf(" alarm"); 78 break; 79 80 case PLUS_SEC: 81 printf(" +1s"); 82 break; 83 84 case MINUS_SEC: 85 printf(" -1s"); 86 break; 87 } 88 89 mode = bp->status & MODEMASK; 90 switch (mode) { 91 92 case MODE_UNSPEC: /* unspecified */ 93 printf(" unspec"); 94 break; 95 96 case MODE_SYM_ACT: /* symmetric active */ 97 printf(" sym_act"); 98 break; 99 100 case MODE_SYM_PAS: /* symmetric passive */ 101 printf(" sym_pas"); 102 break; 103 104 case MODE_CLIENT: /* client */ 105 printf(" client"); 106 break; 107 108 case MODE_SERVER: /* server */ 109 printf(" server"); 110 break; 111 112 case MODE_BROADCAST: /* broadcast */ 113 printf(" bcast"); 114 break; 115 116 case MODE_RES1: /* reserved */ 117 printf(" res1"); 118 break; 119 120 case MODE_RES2: /* reserved */ 121 printf(" res2"); 122 break; 123 124 } 125 126 TCHECK(bp->stratum); 127 printf(" strat %d", bp->stratum); 128 129 TCHECK(bp->ppoll); 130 printf(" poll %d", bp->ppoll); 131 132 /* Can't TCHECK bp->precision bitfield so bp->distance + 0 instead */ 133 TCHECK2(bp->distance, 0); 134 printf(" prec %d", bp->precision); 135 136 if (!vflag) 137 return; 138 139 TCHECK(bp->distance); 140 printf(" dist "); 141 p_sfix(&bp->distance); 142 143 TCHECK(bp->dispersion); 144 printf(" disp "); 145 p_sfix(&bp->dispersion); 146 147 TCHECK(bp->refid); 148 printf(" ref "); 149 /* Interpretation depends on stratum */ 150 switch (bp->stratum) { 151 152 case UNSPECIFIED: 153 printf("(unspec)"); 154 break; 155 156 case PRIM_REF: 157 fn_printn((u_char *)&bp->refid, sizeof(bp->refid), NULL); 158 break; 159 160 case INFO_QUERY: 161 printf("%s INFO_QUERY", ipaddr_string(&(bp->refid))); 162 /* this doesn't have more content */ 163 return; 164 165 case INFO_REPLY: 166 printf("%s INFO_REPLY", ipaddr_string(&(bp->refid))); 167 /* this is too complex to be worth printing */ 168 return; 169 170 default: 171 printf("%s", ipaddr_string(&(bp->refid))); 172 break; 173 } 174 175 TCHECK(bp->reftime); 176 putchar('@'); 177 p_ntp_time(&(bp->reftime)); 178 179 TCHECK(bp->org); 180 printf(" orig "); 181 p_ntp_time(&(bp->org)); 182 183 TCHECK(bp->rec); 184 printf(" rec "); 185 p_ntp_delta(&(bp->org), &(bp->rec)); 186 187 TCHECK(bp->xmt); 188 printf(" xmt "); 189 p_ntp_delta(&(bp->org), &(bp->xmt)); 190 191 return; 192 193 trunc: 194 printf(" [|ntp]"); 195 } 196 197 static void 198 p_sfix(const struct s_fixedpt *sfp) 199 { 200 int i; 201 int f; 202 float ff; 203 204 i = ntohs(sfp->int_part); 205 f = ntohs(sfp->fraction); 206 ff = f / 65536.0; /* shift radix point by 16 bits */ 207 f = ff * 1000000.0; /* Treat fraction as parts per million */ 208 printf("%d.%06d", i, f); 209 } 210 211 #define FMAXINT (4294967296.0) /* floating point rep. of MAXINT */ 212 213 static void 214 p_ntp_time(const struct l_fixedpt *lfp) 215 { 216 int32_t i; 217 u_int32_t uf; 218 u_int32_t f; 219 float ff; 220 221 i = ntohl(lfp->int_part); 222 uf = ntohl(lfp->fraction); 223 ff = uf; 224 if (ff < 0.0) /* some compilers are buggy */ 225 ff += FMAXINT; 226 ff = ff / FMAXINT; /* shift radix point by 32 bits */ 227 f = ff * 1000000000.0; /* treat fraction as parts per billion */ 228 printf("%u.%09d", i, f); 229 } 230 231 /* Prints time difference between *lfp and *olfp */ 232 static void 233 p_ntp_delta(const struct l_fixedpt *olfp, const struct l_fixedpt *lfp) 234 { 235 int32_t i; 236 u_int32_t uf; 237 u_int32_t ouf; 238 u_int32_t f; 239 float ff; 240 int signbit; 241 242 i = ntohl(lfp->int_part) - ntohl(olfp->int_part); 243 244 uf = ntohl(lfp->fraction); 245 ouf = ntohl(olfp->fraction); 246 247 if (i > 0) { /* new is definitely greater than old */ 248 signbit = 0; 249 f = uf - ouf; 250 if (ouf > uf) /* must borrow from high-order bits */ 251 i -= 1; 252 } else if (i < 0) { /* new is definitely less than old */ 253 signbit = 1; 254 f = ouf - uf; 255 if (uf > ouf) /* must carry into the high-order bits */ 256 i += 1; 257 i = -i; 258 } else { /* int_part is zero */ 259 if (uf > ouf) { 260 signbit = 0; 261 f = uf - ouf; 262 } else { 263 signbit = 1; 264 f = ouf - uf; 265 } 266 } 267 268 ff = f; 269 if (ff < 0.0) /* some compilers are buggy */ 270 ff += FMAXINT; 271 ff = ff / FMAXINT; /* shift radix point by 32 bits */ 272 f = ff * 1000000000.0; /* treat fraction as parts per billion */ 273 if (signbit) 274 putchar('-'); 275 else 276 putchar('+'); 277 printf("%d.%09d", i, f); 278 } 279