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