1 /* $NetBSD: ntp_filegen.c,v 1.9 2020/05/25 20:47:25 christos Exp $ */ 2 3 /* 4 * ntp_filegen.c,v 3.12 1994/01/25 19:06:11 kardel Exp 5 * 6 * implements file generations support for NTP 7 * logfiles and statistic files 8 * 9 * 10 * Copyright (C) 1992, 1996 by Rainer Pruy 11 * Friedrich-Alexander Universitaet Erlangen-Nuernberg, Germany 12 * 13 * This code may be modified and used freely 14 * provided credits remain intact. 15 */ 16 17 #ifdef HAVE_CONFIG_H 18 # include <config.h> 19 #endif 20 21 #include <stdio.h> 22 #include <sys/types.h> 23 #include <sys/stat.h> 24 25 #include "ntpd.h" 26 #include "ntp_io.h" 27 #include "ntp_string.h" 28 #include "ntp_calendar.h" 29 #include "ntp_filegen.h" 30 #include "ntp_stdlib.h" 31 32 /* 33 * NTP is intended to run long periods of time without restart. 34 * Thus log and statistic files generated by NTP will grow large. 35 * 36 * this set of routines provides a central interface 37 * to generating files using file generations 38 * 39 * the generation of a file is changed according to file generation type 40 */ 41 42 43 /* 44 * redefine this if your system dislikes filename suffixes like 45 * X.19910101 or X.1992W50 or .... 46 */ 47 #define SUFFIX_SEP '.' 48 49 static void filegen_open (FILEGEN *, u_int32, const time_t*); 50 static int valid_fileref (const char *, const char *); 51 static void filegen_init (const char *, const char *, FILEGEN *); 52 #ifdef DEBUG 53 static void filegen_uninit (FILEGEN *); 54 #endif /* DEBUG */ 55 56 57 /* 58 * filegen_init 59 */ 60 61 static void 62 filegen_init( 63 const char * dir, 64 const char * fname, 65 FILEGEN * fgp 66 ) 67 { 68 fgp->fp = NULL; 69 fgp->dir = estrdup(dir); 70 fgp->fname = estrdup(fname); 71 fgp->id_lo = 0; 72 fgp->id_hi = 0; 73 fgp->type = FILEGEN_DAY; 74 fgp->flag = FGEN_FLAG_LINK; /* not yet enabled !!*/ 75 } 76 77 78 /* 79 * filegen_uninit - free memory allocated by filegen_init 80 */ 81 #ifdef DEBUG 82 static void 83 filegen_uninit( 84 FILEGEN *fgp 85 ) 86 { 87 free(fgp->dir); 88 free(fgp->fname); 89 } 90 #endif 91 92 93 /* 94 * open a file generation according to the current settings of gen 95 * will also provide a link to basename if requested to do so 96 */ 97 98 static void 99 filegen_open( 100 FILEGEN * gen, 101 u_int32 stamp, 102 const time_t * pivot 103 ) 104 { 105 char *savename; /* temp store for name collision handling */ 106 char *fullname; /* name with any designation extension */ 107 char *filename; /* name without designation extension */ 108 char *suffix; /* where to print suffix extension */ 109 u_int len, suflen; 110 FILE *fp; 111 struct calendar cal; 112 struct isodate iso; 113 114 /* get basic filename in buffer, leave room for extensions */ 115 len = strlen(gen->dir) + strlen(gen->fname) + 65; 116 filename = emalloc(len); 117 fullname = emalloc(len); 118 savename = NULL; 119 snprintf(filename, len, "%s%s", gen->dir, gen->fname); 120 121 /* where to place suffix */ 122 suflen = strlcpy(fullname, filename, len); 123 suffix = fullname + suflen; 124 suflen = len - suflen; 125 126 /* last octet of fullname set to '\0' for truncation check */ 127 fullname[len - 1] = '\0'; 128 129 switch (gen->type) { 130 131 default: 132 msyslog(LOG_ERR, 133 "unsupported file generations type %d for " 134 "\"%s\" - reverting to FILEGEN_NONE", 135 gen->type, filename); 136 gen->type = FILEGEN_NONE; 137 break; 138 139 case FILEGEN_NONE: 140 /* no suffix, all set */ 141 break; 142 143 case FILEGEN_PID: 144 gen->id_lo = getpid(); 145 gen->id_hi = 0; 146 snprintf(suffix, suflen, "%c#%ld", 147 SUFFIX_SEP, gen->id_lo); 148 break; 149 150 case FILEGEN_DAY: 151 /* 152 * You can argue here in favor of using MJD, but I 153 * would assume it to be easier for humans to interpret 154 * dates in a format they are used to in everyday life. 155 */ 156 ntpcal_ntp_to_date(&cal, stamp, pivot); 157 snprintf(suffix, suflen, "%c%04d%02d%02d", 158 SUFFIX_SEP, cal.year, cal.month, cal.monthday); 159 cal.hour = cal.minute = cal.second = 0; 160 gen->id_lo = ntpcal_date_to_ntp(&cal); 161 gen->id_hi = (u_int32)(gen->id_lo + SECSPERDAY); 162 break; 163 164 case FILEGEN_WEEK: 165 isocal_ntp_to_date(&iso, stamp, pivot); 166 snprintf(suffix, suflen, "%c%04dw%02d", 167 SUFFIX_SEP, iso.year, iso.week); 168 iso.hour = iso.minute = iso.second = 0; 169 iso.weekday = 1; 170 gen->id_lo = isocal_date_to_ntp(&iso); 171 gen->id_hi = (u_int32)(gen->id_lo + 7 * SECSPERDAY); 172 break; 173 174 case FILEGEN_MONTH: 175 ntpcal_ntp_to_date(&cal, stamp, pivot); 176 snprintf(suffix, suflen, "%c%04d%02d", 177 SUFFIX_SEP, cal.year, cal.month); 178 cal.hour = cal.minute = cal.second = 0; 179 cal.monthday = 1; 180 gen->id_lo = ntpcal_date_to_ntp(&cal); 181 cal.month++; 182 gen->id_hi = ntpcal_date_to_ntp(&cal); 183 break; 184 185 case FILEGEN_YEAR: 186 ntpcal_ntp_to_date(&cal, stamp, pivot); 187 snprintf(suffix, suflen, "%c%04d", 188 SUFFIX_SEP, cal.year); 189 cal.hour = cal.minute = cal.second = 0; 190 cal.month = cal.monthday = 1; 191 gen->id_lo = ntpcal_date_to_ntp(&cal); 192 cal.year++; 193 gen->id_hi = ntpcal_date_to_ntp(&cal); 194 break; 195 196 case FILEGEN_AGE: 197 gen->id_lo = current_time - (current_time % SECSPERDAY); 198 gen->id_hi = gen->id_lo + SECSPERDAY; 199 snprintf(suffix, suflen, "%ca%08ld", 200 SUFFIX_SEP, gen->id_lo); 201 } 202 203 /* check possible truncation */ 204 if ('\0' != fullname[len - 1]) { 205 fullname[len - 1] = '\0'; 206 msyslog(LOG_ERR, "logfile name truncated: \"%s\"", 207 fullname); 208 } 209 210 if (FILEGEN_NONE != gen->type) { 211 /* 212 * check for existence of a file with name 'basename' 213 * as we disallow such a file 214 * if FGEN_FLAG_LINK is set create a link 215 */ 216 struct stat stats; 217 /* 218 * try to resolve name collisions 219 */ 220 static u_long conflicts = 0; 221 222 #ifndef S_ISREG 223 #define S_ISREG(mode) (((mode) & S_IFREG) == S_IFREG) 224 #endif 225 if (stat(filename, &stats) == 0) { 226 /* Hm, file exists... */ 227 if (S_ISREG(stats.st_mode)) { 228 if (stats.st_nlink <= 1) { 229 /* 230 * Oh, it is not linked - try to save it 231 */ 232 savename = emalloc(len); 233 snprintf(savename, len, 234 "%s%c%dC%lu", 235 filename, SUFFIX_SEP, 236 (int)getpid(), conflicts++); 237 238 if (rename(filename, savename) != 0) 239 msyslog(LOG_ERR, 240 "couldn't save %s: %m", 241 filename); 242 free(savename); 243 } else { 244 /* 245 * there is at least a second link to 246 * this file. 247 * just remove the conflicting one 248 */ 249 if ( 250 #if !defined(VMS) 251 unlink(filename) != 0 252 #else 253 delete(filename) != 0 254 #endif 255 ) 256 msyslog(LOG_ERR, 257 "couldn't unlink %s: %m", 258 filename); 259 } 260 } else { 261 /* 262 * Ehh? Not a regular file ?? strange !!!! 263 */ 264 msyslog(LOG_ERR, 265 "expected regular file for %s " 266 "(found mode 0%lo)", 267 filename, 268 (unsigned long)stats.st_mode); 269 } 270 } else { 271 /* 272 * stat(..) failed, but it is absolutely correct for 273 * 'basename' not to exist 274 */ 275 if (ENOENT != errno) 276 msyslog(LOG_ERR, "stat(%s) failed: %m", 277 filename); 278 } 279 } 280 281 /* 282 * now, try to open new file generation... 283 */ 284 DPRINTF(4, ("opening filegen (type=%d/stamp=%u) \"%s\"\n", 285 gen->type, stamp, fullname)); 286 287 fp = fopen(fullname, "a"); 288 289 if (NULL == fp) { 290 /* open failed -- keep previous state 291 * 292 * If the file was open before keep the previous generation. 293 * This will cause output to end up in the 'wrong' file, 294 * but I think this is still better than losing output 295 * 296 * ignore errors due to missing directories 297 */ 298 299 if (ENOENT != errno) 300 msyslog(LOG_ERR, "can't open %s: %m", fullname); 301 } else { 302 if (NULL != gen->fp) { 303 fclose(gen->fp); 304 gen->fp = NULL; 305 } 306 gen->fp = fp; 307 308 if (gen->flag & FGEN_FLAG_LINK) { 309 /* 310 * need to link file to basename 311 * have to use hardlink for now as I want to allow 312 * gen->basename spanning directory levels 313 * this would make it more complex to get the correct 314 * fullname for symlink 315 * 316 * Ok, it would just mean taking the part following 317 * the last '/' in the name.... Should add it later.... 318 */ 319 320 /* Windows NT does not support file links -Greg Schueman 1/18/97 */ 321 322 #if defined(SYS_WINNT) || defined(SYS_VXWORKS) 323 SetLastError(0); /* On WinNT, don't support FGEN_FLAG_LINK */ 324 #elif defined(VMS) 325 errno = 0; /* On VMS, don't support FGEN_FLAG_LINK */ 326 #else /* not (VMS) / VXWORKS / WINNT ; DO THE LINK) */ 327 if (link(fullname, filename) != 0) 328 if (EEXIST != errno) 329 msyslog(LOG_ERR, 330 "can't link(%s, %s): %m", 331 fullname, filename); 332 #endif /* SYS_WINNT || VXWORKS */ 333 } /* flags & FGEN_FLAG_LINK */ 334 } /* else fp == NULL */ 335 336 free(filename); 337 free(fullname); 338 return; 339 } 340 341 /* 342 * this function sets up gen->fp to point to the correct 343 * generation of the file for the time specified by 'now' 344 * 345 * 'now' usually is interpreted as second part of a l_fp as is in the cal... 346 * library routines 347 */ 348 349 void 350 filegen_setup( 351 FILEGEN * gen, 352 u_int32 now 353 ) 354 { 355 int current; 356 time_t pivot; 357 358 if (!(gen->flag & FGEN_FLAG_ENABLED)) { 359 if (NULL != gen->fp) { 360 fclose(gen->fp); 361 gen->fp = NULL; 362 } 363 return; 364 } 365 366 switch (gen->type) { 367 368 default: 369 case FILEGEN_NONE: 370 current = TRUE; 371 break; 372 373 case FILEGEN_PID: 374 current = ((int)gen->id_lo == getpid()); 375 break; 376 377 case FILEGEN_AGE: 378 current = (gen->id_lo <= current_time) && 379 (gen->id_hi > current_time); 380 break; 381 382 case FILEGEN_DAY: 383 case FILEGEN_WEEK: 384 case FILEGEN_MONTH: 385 case FILEGEN_YEAR: 386 current = (gen->id_lo <= now) && 387 (gen->id_hi > now); 388 break; 389 } 390 /* 391 * try to open file if not yet open 392 * reopen new file generation file on change of generation id 393 */ 394 if (NULL == gen->fp || !current) { 395 DPRINTF(1, ("filegen %0x %u\n", gen->type, now)); 396 pivot = time(NULL); 397 filegen_open(gen, now, &pivot); 398 } 399 } 400 401 402 /* 403 * change settings for filegen files 404 */ 405 void 406 filegen_config( 407 FILEGEN * gen, 408 const char * dir, 409 const char * fname, 410 u_int type, 411 u_int flag 412 ) 413 { 414 int file_existed; 415 l_fp now; 416 417 418 /* 419 * if nothing would be changed... 420 */ 421 if (strcmp(dir, gen->dir) == 0 && strcmp(fname, gen->fname) == 0 422 && type == gen->type && flag == gen->flag) 423 return; 424 425 /* 426 * validate parameters 427 */ 428 if (!valid_fileref(dir, fname)) 429 return; 430 431 if (NULL != gen->fp) { 432 fclose(gen->fp); 433 gen->fp = NULL; 434 file_existed = TRUE; 435 } else { 436 file_existed = FALSE; 437 } 438 439 DPRINTF(3, ("configuring filegen:\n" 440 "\tdir:\t%s -> %s\n" 441 "\tfname:\t%s -> %s\n" 442 "\ttype:\t%d -> %d\n" 443 "\tflag: %x -> %x\n", 444 gen->dir, dir, 445 gen->fname, fname, 446 gen->type, type, 447 gen->flag, flag)); 448 449 if (strcmp(gen->dir, dir) != 0) { 450 free(gen->dir); 451 gen->dir = estrdup(dir); 452 } 453 454 if (strcmp(gen->fname, fname) != 0) { 455 free(gen->fname); 456 gen->fname = estrdup(fname); 457 } 458 gen->type = (u_char)type; 459 gen->flag = (u_char)flag; 460 461 /* 462 * make filegen use the new settings 463 * special action is only required when a generation file 464 * is currently open 465 * otherwise the new settings will be used anyway at the next open 466 */ 467 if (file_existed) { 468 get_systime(&now); 469 filegen_setup(gen, now.l_ui); 470 } 471 } 472 473 474 /* 475 * check whether concatenating prefix and basename 476 * yields a legal filename 477 */ 478 static int 479 valid_fileref( 480 const char * dir, 481 const char * fname 482 ) 483 { 484 /* 485 * dir cannot be changed dynamically 486 * (within the context of filegen) 487 * so just reject basenames containing '..' 488 * 489 * ASSUMPTION: 490 * file system parts 'below' dir may be 491 * specified without infringement of security 492 * 493 * restricting dir to legal values 494 * has to be ensured by other means 495 * (however, it would be possible to perform some checks here...) 496 */ 497 const char *p; 498 499 /* 500 * Just to catch, dumb errors opening up the world... 501 */ 502 if (NULL == dir || '\0' == dir[0]) 503 return FALSE; 504 505 if (NULL == fname) 506 return FALSE; 507 508 #ifdef SYS_WINNT 509 /* 510 * Windows treats / equivalent to \, reject any / to ensure 511 * check below for DIR_SEP (\ on windows) are adequate. 512 */ 513 if (strchr(fname, '/')) { 514 msyslog(LOG_ERR, 515 "filegen filenames must not contain '/': %s", 516 fname); 517 return FALSE; 518 } 519 #endif 520 521 for (p = fname; p != NULL; p = strchr(p, DIR_SEP)) { 522 if ('.' == p[0] && '.' == p[1] 523 && ('\0' == p[2] || DIR_SEP == p[2])) 524 return FALSE; 525 } 526 527 return TRUE; 528 } 529 530 531 /* 532 * filegen registry 533 */ 534 535 static struct filegen_entry { 536 char * name; 537 FILEGEN * filegen; 538 struct filegen_entry * next; 539 } *filegen_registry = NULL; 540 541 542 FILEGEN * 543 filegen_get( 544 const char * name 545 ) 546 { 547 struct filegen_entry *f = filegen_registry; 548 549 while (f) { 550 if (f->name == name || strcmp(name, f->name) == 0) { 551 DPRINTF(4, ("filegen_get(%s) = %p\n", 552 name, f->filegen)); 553 return f->filegen; 554 } 555 f = f->next; 556 } 557 DPRINTF(4, ("filegen_get(%s) = NULL\n", name)); 558 return NULL; 559 } 560 561 562 void 563 filegen_register( 564 const char * dir, 565 const char * name, 566 FILEGEN * filegen 567 ) 568 { 569 struct filegen_entry **ppfe; 570 571 DPRINTF(4, ("filegen_register(%s, %p)\n", name, filegen)); 572 573 filegen_init(dir, name, filegen); 574 575 ppfe = &filegen_registry; 576 while (NULL != *ppfe) { 577 if ((*ppfe)->name == name 578 || !strcmp((*ppfe)->name, name)) { 579 580 DPRINTF(5, ("replacing filegen %p\n", 581 (*ppfe)->filegen)); 582 583 (*ppfe)->filegen = filegen; 584 return; 585 } 586 ppfe = &((*ppfe)->next); 587 } 588 589 *ppfe = emalloc(sizeof **ppfe); 590 591 (*ppfe)->next = NULL; 592 (*ppfe)->name = estrdup(name); 593 (*ppfe)->filegen = filegen; 594 595 DPRINTF(6, ("adding new filegen\n")); 596 597 return; 598 } 599 600 601 /* 602 * filegen_statsdir() - reset each filegen entry's dir to statsdir. 603 */ 604 void 605 filegen_statsdir(void) 606 { 607 struct filegen_entry *f; 608 609 for (f = filegen_registry; f != NULL; f = f->next) 610 filegen_config(f->filegen, statsdir, f->filegen->fname, 611 f->filegen->type, f->filegen->flag); 612 } 613 614 615 /* 616 * filegen_unregister frees memory allocated by filegen_register for 617 * name. 618 */ 619 #ifdef DEBUG 620 void 621 filegen_unregister( 622 const char *name 623 ) 624 { 625 struct filegen_entry ** ppfe; 626 struct filegen_entry * pfe; 627 FILEGEN * fg; 628 629 DPRINTF(4, ("filegen_unregister(%s)\n", name)); 630 631 ppfe = &filegen_registry; 632 633 while (NULL != *ppfe) { 634 if ((*ppfe)->name == name 635 || !strcmp((*ppfe)->name, name)) { 636 pfe = *ppfe; 637 *ppfe = (*ppfe)->next; 638 fg = pfe->filegen; 639 free(pfe->name); 640 free(pfe); 641 filegen_uninit(fg); 642 break; 643 } 644 ppfe = &((*ppfe)->next); 645 } 646 } 647 #endif /* DEBUG */ 648