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
filegen_init(const char * dir,const char * fname,FILEGEN * fgp)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
filegen_uninit(FILEGEN * fgp)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
filegen_open(FILEGEN * gen,u_int32 stamp,const time_t * pivot)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
filegen_setup(FILEGEN * gen,u_int32 now)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
filegen_config(FILEGEN * gen,const char * dir,const char * fname,u_int type,u_int flag)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
valid_fileref(const char * dir,const char * fname)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 *
filegen_get(const char * name)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
filegen_register(const char * dir,const char * name,FILEGEN * filegen)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
filegen_statsdir(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
filegen_unregister(const char * name)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