File: master-settings.c

package info (click to toggle)
dovecot 1:2.2.13-12~deb8u4
  • links: PTS, VCS
  • area: main
  • in suites: jessie
  • size: 38,792 kB
  • sloc: ansic: 341,472; sh: 16,920; makefile: 5,393; cpp: 1,474; perl: 265; xml: 44; python: 34; pascal: 27
file content (775 lines) | stat: -rw-r--r-- 21,985 bytes parent folder | download | duplicates (3)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
/* Copyright (c) 2005-2014 Dovecot authors, see the included COPYING file */

#include "common.h"
#include "array.h"
#include "env-util.h"
#include "istream.h"
#include "net.h"
#include "str.h"
#include "ipwd.h"
#include "mkdir-parents.h"
#include "safe-mkdir.h"
#include "restrict-process-size.h"
#include "settings-parser.h"
#include "master-settings.h"

#include <stddef.h>
#include <dirent.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/wait.h>

static bool master_settings_verify(void *_set, pool_t pool,
				   const char **error_r);

extern const struct setting_parser_info service_setting_parser_info;

#undef DEF
#define DEF(type, name) \
	{ type, #name, offsetof(struct file_listener_settings, name), NULL }

static const struct setting_define file_listener_setting_defines[] = {
	DEF(SET_STR, path),
	DEF(SET_UINT_OCT, mode),
	DEF(SET_STR, user),
	DEF(SET_STR, group),

	SETTING_DEFINE_LIST_END
};

static const struct file_listener_settings file_listener_default_settings = {
	.path = "",
	.mode = 0600,
	.user = "",
	.group = "",
};

static const struct setting_parser_info file_listener_setting_parser_info = {
	.defines = file_listener_setting_defines,
	.defaults = &file_listener_default_settings,

	.type_offset = offsetof(struct file_listener_settings, path),
	.struct_size = sizeof(struct file_listener_settings),

	.parent_offset = (size_t)-1,
	.parent = &service_setting_parser_info
};

#undef DEF
#define DEF(type, name) \
	{ type, #name, offsetof(struct inet_listener_settings, name), NULL }

static const struct setting_define inet_listener_setting_defines[] = {
	DEF(SET_STR, name),
	DEF(SET_STR, address),
	DEF(SET_UINT, port),
	DEF(SET_BOOL, ssl),
	DEF(SET_BOOL, reuse_port),

	SETTING_DEFINE_LIST_END
};

static const struct inet_listener_settings inet_listener_default_settings = {
	.name = "",
	.address = "",
	.port = 0,
	.ssl = FALSE,
	.reuse_port = FALSE
};

static const struct setting_parser_info inet_listener_setting_parser_info = {
	.defines = inet_listener_setting_defines,
	.defaults = &inet_listener_default_settings,

	.type_offset = offsetof(struct inet_listener_settings, name),
	.struct_size = sizeof(struct inet_listener_settings),

	.parent_offset = (size_t)-1,
	.parent = &service_setting_parser_info
};

#undef DEF
#undef DEFLIST
#undef DEFLIST_UNIQUE
#define DEF(type, name) \
	{ type, #name, offsetof(struct service_settings, name), NULL }
#define DEFLIST(field, name, defines) \
	{ SET_DEFLIST, name, offsetof(struct service_settings, field), defines }
#define DEFLIST_UNIQUE(field, name, defines) \
	{ SET_DEFLIST_UNIQUE, name, offsetof(struct service_settings, field), defines }

static const struct setting_define service_setting_defines[] = {
	DEF(SET_STR, name),
	DEF(SET_STR, protocol),
	DEF(SET_STR, type),
	DEF(SET_STR, executable),
	DEF(SET_STR, user),
	DEF(SET_STR, group),
	DEF(SET_STR, privileged_group),
	DEF(SET_STR, extra_groups),
	DEF(SET_STR, chroot),

	DEF(SET_BOOL, drop_priv_before_exec),

	DEF(SET_UINT, process_min_avail),
	DEF(SET_UINT, process_limit),
	DEF(SET_UINT, client_limit),
	DEF(SET_UINT, service_count),
	DEF(SET_TIME, idle_kill),
	DEF(SET_SIZE, vsz_limit),

	DEFLIST_UNIQUE(unix_listeners, "unix_listener",
		       &file_listener_setting_parser_info),
	DEFLIST_UNIQUE(fifo_listeners, "fifo_listener",
		       &file_listener_setting_parser_info),
	DEFLIST_UNIQUE(inet_listeners, "inet_listener",
		       &inet_listener_setting_parser_info),

	SETTING_DEFINE_LIST_END
};

static const struct service_settings service_default_settings = {
	.name = "",
	.protocol = "",
	.type = "",
	.executable = "",
	.user = "",
	.group = "",
	.privileged_group = "",
	.extra_groups = "",
	.chroot = "",

	.drop_priv_before_exec = FALSE,

	.process_min_avail = 0,
	.process_limit = 0,
	.client_limit = 0,
	.service_count = 0,
	.idle_kill = 0,
	.vsz_limit = (uoff_t)-1,

	.unix_listeners = ARRAY_INIT,
	.fifo_listeners = ARRAY_INIT,
	.inet_listeners = ARRAY_INIT
};

const struct setting_parser_info service_setting_parser_info = {
	.defines = service_setting_defines,
	.defaults = &service_default_settings,

	.type_offset = offsetof(struct service_settings, name),
	.struct_size = sizeof(struct service_settings),

	.parent_offset = offsetof(struct service_settings, master_set),
	.parent = &master_setting_parser_info
};

#undef DEF
#undef DEFLIST_UNIQUE
#define DEF(type, name) \
	{ type, #name, offsetof(struct master_settings, name), NULL }
#define DEFLIST_UNIQUE(field, name, defines) \
	{ SET_DEFLIST_UNIQUE, name, offsetof(struct master_settings, field), defines }

static const struct setting_define master_setting_defines[] = {
	DEF(SET_STR, base_dir),
	DEF(SET_STR, state_dir),
	DEF(SET_STR, libexec_dir),
	DEF(SET_STR, instance_name),
	DEF(SET_STR, import_environment),
	DEF(SET_STR, protocols),
	DEF(SET_STR, listen),
	DEF(SET_ENUM, ssl),
	DEF(SET_STR, default_internal_user),
	DEF(SET_STR, default_login_user),
	DEF(SET_UINT, default_process_limit),
	DEF(SET_UINT, default_client_limit),
	DEF(SET_TIME, default_idle_kill),
	DEF(SET_SIZE, default_vsz_limit),

	DEF(SET_BOOL, version_ignore),

	DEF(SET_UINT, first_valid_uid),
	DEF(SET_UINT, last_valid_uid),
	DEF(SET_UINT, first_valid_gid),
	DEF(SET_UINT, last_valid_gid),

	DEFLIST_UNIQUE(services, "service", &service_setting_parser_info),

	SETTING_DEFINE_LIST_END
};

/* <settings checks> */
#ifdef HAVE_SYSTEMD
#  define ENV_SYSTEMD " LISTEN_PID LISTEN_FDS"
#else
#  define ENV_SYSTEMD ""
#endif
#ifdef DEBUG
#  define ENV_GDB " GDB DEBUG_SILENT"
#else
#  define ENV_GDB ""
#endif
/* </settings checks> */

static const struct master_settings master_default_settings = {
	.base_dir = PKG_RUNDIR,
	.state_dir = PKG_STATEDIR,
	.libexec_dir = PKG_LIBEXECDIR,
	.instance_name = PACKAGE,
	.import_environment = "TZ CORE_OUTOFMEM CORE_ERROR" ENV_SYSTEMD ENV_GDB,
	.protocols = "",
	.listen = "*, ::",
	.ssl = "yes:no:required",
	.default_internal_user = "dovecot",
	.default_login_user = "dovenull",
	.default_process_limit = 100,
	.default_client_limit = 1000,
	.default_idle_kill = 60,
	.default_vsz_limit = 256*1024*1024,

	.version_ignore = FALSE,

	.first_valid_uid = 500,
	.last_valid_uid = 0,
	.first_valid_gid = 1,
	.last_valid_gid = 0,

#ifndef CONFIG_BINARY
	.services = ARRAY_INIT
#else
	.services = { { &config_all_services_buf,
			     sizeof(struct service_settings *) } },
#endif
};

const struct setting_parser_info master_setting_parser_info = {
	.module_name = "master",
	.defines = master_setting_defines,
	.defaults = &master_default_settings,

	.type_offset = (size_t)-1,
	.struct_size = sizeof(struct master_settings),

	.parent_offset = (size_t)-1,

	.check_func = master_settings_verify
};

/* <settings checks> */
static void
expand_user(const char **user, enum service_user_default *default_r,
	    const struct master_settings *set)
{
	/* $variable expansion is typically done by doveconf, but these
	   variables can come from built-in settings, so we need to expand
	   them here */
	if (strcmp(*user, "$default_internal_user") == 0) {
		*user = set->default_internal_user;
		*default_r = SERVICE_USER_DEFAULT_INTERNAL;
	} else if (strcmp(*user, "$default_login_user") == 0) {
		*user = set->default_login_user;
		*default_r = SERVICE_USER_DEFAULT_LOGIN;
	} else {
		*default_r = SERVICE_USER_DEFAULT_NONE;
	}
}

static void
fix_file_listener_paths(ARRAY_TYPE(file_listener_settings) *l,
			pool_t pool, const struct master_settings *master_set,
			ARRAY_TYPE(const_string) *all_listeners)
{
	struct file_listener_settings *const *sets;
	unsigned int base_dir_len = strlen(master_set->base_dir);
	enum service_user_default user_default;

	if (!array_is_created(l))
		return;

	array_foreach(l, sets) {
		struct file_listener_settings *set = *sets;

		expand_user(&set->user, &user_default, master_set);
		if (*set->path != '/') {
			set->path = p_strconcat(pool, master_set->base_dir, "/",
						set->path, NULL);
		} else if (strncmp(set->path, master_set->base_dir,
				   base_dir_len) == 0 &&
			   set->path[base_dir_len] == '/') {
			i_warning("You should remove base_dir prefix from "
				  "unix_listener: %s", set->path);
		}
		if (set->mode != 0)
			array_append(all_listeners, &set->path, 1);
	}
}

static void add_inet_listeners(ARRAY_TYPE(inet_listener_settings) *l,
			       ARRAY_TYPE(const_string) *all_listeners)
{
	struct inet_listener_settings *const *sets;
	const char *str;

	if (!array_is_created(l))
		return;

	array_foreach(l, sets) {
		struct inet_listener_settings *set = *sets;

		if (set->port != 0) {
			str = t_strdup_printf("%d:%s", set->port, set->address);
			array_append(all_listeners, &str, 1);
		}
	}
}

static bool master_settings_parse_type(struct service_settings *set,
				       const char **error_r)
{
	if (*set->type == '\0')
		set->parsed_type = SERVICE_TYPE_UNKNOWN;
	else if (strcmp(set->type, "log") == 0)
		set->parsed_type = SERVICE_TYPE_LOG;
	else if (strcmp(set->type, "config") == 0)
		set->parsed_type = SERVICE_TYPE_CONFIG;
	else if (strcmp(set->type, "anvil") == 0)
		set->parsed_type = SERVICE_TYPE_ANVIL;
	else if (strcmp(set->type, "login") == 0)
		set->parsed_type = SERVICE_TYPE_LOGIN;
	else if (strcmp(set->type, "startup") == 0)
		set->parsed_type = SERVICE_TYPE_STARTUP;
	else {
		*error_r = t_strconcat("Unknown service type: ",
				       set->type, NULL);
		return FALSE;
	}
	return TRUE;
}

static void service_set_login_dump_core(struct service_settings *set)
{
	const char *p;

	if (set->parsed_type != SERVICE_TYPE_LOGIN)
		return;

	p = strstr(set->executable, " -D");
	if (p != NULL && (p[3] == '\0' || p[3] == ' '))
		set->login_dump_core = TRUE;
}

static bool
services_have_protocol(struct master_settings *set, const char *name)
{
	struct service_settings *const *services;

	array_foreach(&set->services, services) {
		struct service_settings *service = *services;

		if (strcmp(service->protocol, name) == 0)
			return TRUE;
	}
	return FALSE;
}

#ifdef CONFIG_BINARY
static const struct service_settings *
master_default_settings_get_service(const char *name)
{
	extern struct master_settings master_default_settings;
	struct service_settings *const *setp;

	array_foreach(&master_default_settings.services, setp) {
		if (strcmp((*setp)->name, name) == 0)
			return *setp;
	}
	return NULL;
}
#endif

static unsigned int
service_get_client_limit(struct master_settings *set, const char *name)
{
	struct service_settings *const *servicep;

	array_foreach(&set->services, servicep) {
		if (strcmp((*servicep)->name, name) == 0) {
			if ((*servicep)->client_limit != 0)
				return (*servicep)->client_limit;
			else
				return set->default_client_limit;
		}
	}
	return set->default_client_limit;
}

static bool
master_settings_verify(void *_set, pool_t pool, const char **error_r)
{
	static int warned_auth = FALSE, warned_anvil = FALSE;
	struct master_settings *set = _set;
	struct service_settings *const *services;
	const char *const *strings;
	ARRAY_TYPE(const_string) all_listeners;
	struct passwd pw;
	unsigned int i, j, count, len, client_limit, process_limit;
	unsigned int max_auth_client_processes, max_anvil_client_processes;
#ifdef CONFIG_BINARY
	const struct service_settings *default_service;
#else
	rlim_t fd_limit;
	const char *max_client_limit_source = "default_client_limit";
	unsigned int max_client_limit = set->default_client_limit;
#endif

	len = strlen(set->base_dir);
	if (len > 0 && set->base_dir[len-1] == '/') {
		/* drop trailing '/' */
		set->base_dir = p_strndup(pool, set->base_dir, len - 1);
	}

	if (set->last_valid_uid != 0 &&
	    set->first_valid_uid > set->last_valid_uid) {
		*error_r = "first_valid_uid can't be larger than last_valid_uid";
		return FALSE;
	}
	if (set->last_valid_gid != 0 &&
	    set->first_valid_gid > set->last_valid_gid) {
		*error_r = "first_valid_gid can't be larger than last_valid_gid";
		return FALSE;
	}

	if (i_getpwnam(set->default_login_user, &pw) == 0) {
		*error_r = t_strdup_printf("default_login_user doesn't exist: %s",
					   set->default_login_user);
		return FALSE;
	}
	if (i_getpwnam(set->default_internal_user, &pw) == 0) {
		*error_r = t_strdup_printf("default_internal_user doesn't exist: %s",
					   set->default_internal_user);
		return FALSE;
	}

	/* check that we have at least one service. the actual service
	   structure validity is checked later while creating them. */
	if (!array_is_created(&set->services) ||
	    array_count(&set->services) == 0) {
		*error_r = "No services defined";
		return FALSE;
	}
	services = array_get(&set->services, &count);
	for (i = 0; i < count; i++) {
		struct service_settings *service = services[i];

		if (*service->name == '\0') {
			*error_r = t_strdup_printf(
				"Service #%d is missing name", i);
			return FALSE;
		}
		if (!master_settings_parse_type(service, error_r))
			return FALSE;
		for (j = 0; j < i; j++) {
			if (strcmp(service->name, services[j]->name) == 0) {
				*error_r = t_strdup_printf(
					"Duplicate service name: %s",
					service->name);
				return FALSE;
			}
		}
		expand_user(&service->user, &service->user_default, set);
		service_set_login_dump_core(service);
	}
	set->protocols_split = p_strsplit_spaces(pool, set->protocols, " ");
	if (set->protocols_split[0] != NULL &&
	    strcmp(set->protocols_split[0], "none") == 0 &&
	    set->protocols_split[1] == NULL)
		set->protocols_split[0] = NULL;

	for (i = 0; set->protocols_split[i] != NULL; i++) {
		if (!services_have_protocol(set, set->protocols_split[i])) {
			*error_r = t_strdup_printf("protocols: "
						   "Unknown protocol: %s",
						   set->protocols_split[i]);
			return FALSE;
		}
	}
	t_array_init(&all_listeners, 64);
	max_auth_client_processes = 0;
	max_anvil_client_processes = 2; /* blocking, nonblocking pipes */
	for (i = 0; i < count; i++) {
		struct service_settings *service = services[i];

		if (*service->protocol != '\0' &&
		    !str_array_find((const char **)set->protocols_split,
				    service->protocol)) {
			/* protocol not enabled, ignore its settings */
			continue;
		}

		if (*service->executable != '/' &&
		    *service->executable != '\0') {
			service->executable =
				p_strconcat(pool, set->libexec_dir, "/",
					    service->executable, NULL);
		}
		if (*service->chroot != '/' && *service->chroot != '\0') {
			service->chroot =
				p_strconcat(pool, set->base_dir, "/",
					    service->chroot, NULL);
		}
		if (service->drop_priv_before_exec &&
		    *service->chroot != '\0') {
			*error_r = t_strdup_printf("service(%s): "
				"drop_priv_before_exec=yes can't be "
				"used with chroot", service->name);
			return FALSE;
		}
		process_limit = service->process_limit;
		if (process_limit == 0)
			process_limit = set->default_process_limit;
		if (service->process_min_avail > process_limit) {
			*error_r = t_strdup_printf("service(%s): "
				"process_min_avail is higher than process_limit",
				service->name);
			return FALSE;
		}
		if (service->vsz_limit < 1024*1024 && service->vsz_limit != 0) {
			*error_r = t_strdup_printf("service(%s): "
				"vsz_limit is too low", service->name);
			return FALSE;
		}

#ifdef CONFIG_BINARY
		default_service =
			master_default_settings_get_service(service->name);
		if (default_service != NULL &&
		    default_service->process_limit_1 && process_limit > 1) {
			*error_r = t_strdup_printf("service(%s): "
				"process_limit must be 1", service->name);
			return FALSE;
		}
#else
		if (max_client_limit < service->client_limit) {
			max_client_limit = service->client_limit;
			max_client_limit_source = t_strdup_printf(
				"service %s { client_limit }", service->name);
		}
#endif

		if (*service->protocol != '\0') {
			/* each imap/pop3/lmtp process can use up a connection,
			   although if service_count=1 it's only temporary */
			if (service->service_count != 1 ||
			    strcmp(service->type, "login") == 0)
				max_auth_client_processes += process_limit;
		}
		if (strcmp(service->type, "login") == 0 ||
		    strcmp(service->name, "auth") == 0)
			max_anvil_client_processes += process_limit;

		fix_file_listener_paths(&service->unix_listeners,
					pool, set, &all_listeners);
		fix_file_listener_paths(&service->fifo_listeners,
					pool, set, &all_listeners);
		add_inet_listeners(&service->inet_listeners, &all_listeners);
	}

	client_limit = service_get_client_limit(set, "auth");
	if (client_limit < max_auth_client_processes && !warned_auth) {
		warned_auth = TRUE;
		i_warning("service auth { client_limit=%u } is lower than "
			  "required under max. load (%u)",
			  client_limit, max_auth_client_processes);
	}

	client_limit = service_get_client_limit(set, "anvil");
	if (client_limit < max_anvil_client_processes && !warned_anvil) {
		warned_anvil = TRUE;
		i_warning("service anvil { client_limit=%u } is lower than "
			  "required under max. load (%u)",
			  client_limit, max_anvil_client_processes);
	}
#ifndef CONFIG_BINARY
	if (restrict_get_fd_limit(&fd_limit) == 0 &&
	    fd_limit < (rlim_t)max_client_limit) {
		i_warning("fd limit (ulimit -n) is lower than required "
			  "under max. load (%u < %u), because of %s",
			  (unsigned int)fd_limit, max_client_limit,
			  max_client_limit_source);
	}
#endif

	/* check for duplicate listeners */
	array_sort(&all_listeners, i_strcmp_p);
	strings = array_get(&all_listeners, &count);
	for (i = 1; i < count; i++) {
		if (strcmp(strings[i-1], strings[i]) == 0) {
			*error_r = t_strdup_printf("duplicate listener: %s",
						   strings[i]);
			return FALSE;
		}
	}
	return TRUE;
}
/* </settings checks> */

static bool
login_want_core_dumps(const struct master_settings *set, gid_t *gid_r)
{
	struct service_settings *const *services;
	const char *error;
	bool cores = FALSE;
	uid_t uid;

	*gid_r = (gid_t)-1;

	array_foreach(&set->services, services) {
		struct service_settings *service = *services;

		if (service->parsed_type == SERVICE_TYPE_LOGIN) {
			if (service->login_dump_core)
				cores = TRUE;
			(void)get_uidgid(service->user, &uid, gid_r, &error);
			if (*service->group != '\0')
				(void)get_gid(service->group, gid_r, &error);
		}
	}
	return cores;
}

static bool
settings_have_auth_unix_listeners_in(const struct master_settings *set,
				     const char *dir)
{
	struct service_settings *const *services;
	struct file_listener_settings *const *uls;

	array_foreach(&set->services, services) {
		struct service_settings *service = *services;

		if (array_is_created(&service->unix_listeners)) {
			array_foreach(&service->unix_listeners, uls) {
				struct file_listener_settings *u = *uls;

				if (strncmp(u->path, dir, strlen(dir)) == 0)
					return TRUE;
			}
		}
	}
	return FALSE;
}

static void unlink_sockets(const char *path, const char *prefix)
{
	DIR *dirp;
	struct dirent *dp;
	struct stat st;
	string_t *str;
	unsigned int prefix_len;

	dirp = opendir(path);
	if (dirp == NULL) {
		i_error("opendir(%s) failed: %m", path);
		return;
	}

	prefix_len = strlen(prefix);
	str = t_str_new(256);
	while ((dp = readdir(dirp)) != NULL) {
		if (dp->d_name[0] == '.')
			continue;

		if (strncmp(dp->d_name, prefix, prefix_len) != 0)
			continue;

		str_truncate(str, 0);
		str_printfa(str, "%s/%s", path, dp->d_name);
		if (lstat(str_c(str), &st) < 0) {
			if (errno != ENOENT)
				i_error("lstat(%s) failed: %m", str_c(str));
			continue;
		}
		if (!S_ISSOCK(st.st_mode))
			continue;

		/* try to avoid unlinking sockets if someone's already
		   listening in them. do this only at startup, because
		   when SIGHUPing a child process might catch the new
		   connection before it notices that it's supposed
		   to die. null_fd == -1 check is a bit kludgy, but works.. */
		if (null_fd == -1) {
			int fd = net_connect_unix(str_c(str));
			if (fd != -1 || errno != ECONNREFUSED) {
				i_fatal("Dovecot is already running? "
					"Socket already exists: %s",
					str_c(str));
			}
		}

		if (unlink(str_c(str)) < 0 && errno != ENOENT)
			i_error("unlink(%s) failed: %m", str_c(str));
	}
	(void)closedir(dirp);
}

static void
mkdir_login_dir(const struct master_settings *set, const char *login_dir)
{
	mode_t mode;
	gid_t gid;

	if (settings_have_auth_unix_listeners_in(set, login_dir)) {
		/* we are not using external authentication, so make sure the
		   login directory exists with correct permissions and it's
		   empty. with external auth we wouldn't want to delete
		   existing sockets or break the permissions required by the
		   auth server. */
		mode = login_want_core_dumps(set, &gid) ? 0770 : 0750;
		if (safe_mkdir(login_dir, mode, master_uid, gid) == 0) {
			i_warning("Corrected permissions for login directory "
				  "%s", login_dir);
		}

		unlink_sockets(login_dir, "");
	} else {
		/* still make sure that login directory exists */
		if (mkdir(login_dir, 0755) < 0 && errno != EEXIST)
			i_fatal("mkdir(%s) failed: %m", login_dir);
	}
}

void master_settings_do_fixes(const struct master_settings *set)
{
	const char *empty_dir;
	struct stat st;

	/* since base dir is under /var/run by default, it may have been
	   deleted. */
	if (mkdir_parents(set->base_dir, 0755) < 0 && errno != EEXIST)
		i_fatal("mkdir(%s) failed: %m", set->base_dir);
	/* allow base_dir to be a symlink, so don't use lstat() */
	if (stat(set->base_dir, &st) < 0)
		i_fatal("stat(%s) failed: %m", set->base_dir);
	if (!S_ISDIR(st.st_mode))
		i_fatal("%s is not a directory", set->base_dir);
	if ((st.st_mode & 0755) != 0755) {
		i_warning("Fixing permissions of %s to be world-readable",
			  set->base_dir);
		if (chmod(set->base_dir, 0755) < 0)
			i_error("chmod(%s) failed: %m", set->base_dir);
	}

	/* Make sure our permanent state directory exists */
	if (mkdir_parents(set->state_dir, 0755) < 0 && errno != EEXIST)
		i_fatal("mkdir(%s) failed: %m", set->state_dir);

	mkdir_login_dir(set, t_strconcat(set->base_dir, "/login", NULL));
	mkdir_login_dir(set, t_strconcat(set->base_dir, "/token-login", NULL));

	empty_dir = t_strconcat(set->base_dir, "/empty", NULL);
	if (safe_mkdir(empty_dir, 0755, master_uid, getegid()) == 0) {
		i_warning("Corrected permissions for empty directory "
			  "%s", empty_dir);
	}
}