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
|
/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* util_mutex.c: Useful functions for determining allowable
* mutexes and mutex settings
*/
#include "apr.h"
#include "apr_hash.h"
#include "apr_strings.h"
#include "apr_lib.h"
#define APR_WANT_STRFUNC
#include "apr_want.h"
#include "ap_config.h"
#include "httpd.h"
#include "http_main.h"
#include "http_config.h"
#include "http_core.h"
#include "http_log.h"
#include "util_mutex.h"
#if AP_NEED_SET_MUTEX_PERMS
#include "unixd.h"
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h> /* getpid() */
#endif
/* we know core's module_index is 0 */
#undef APLOG_MODULE_INDEX
#define APLOG_MODULE_INDEX AP_CORE_MODULE_INDEX
AP_DECLARE(apr_status_t) ap_parse_mutex(const char *arg, apr_pool_t *pool,
apr_lockmech_e *mutexmech,
const char **mutexfile)
{
/* Split arg into meth and file */
char *meth = apr_pstrdup(pool, arg);
char *file = strchr(meth, ':');
if (file) {
*(file++) = '\0';
if (!*file) {
file = NULL;
}
}
/* APR determines temporary filename unless overridden below,
* we presume file indicates an mutexfile is a file path
* unless the method sets mutexfile=file and NULLs file
*/
*mutexfile = NULL;
if (!strcasecmp(meth, "none") || !strcasecmp(meth, "no")) {
return APR_ENOLOCK;
}
/* NOTE: previously, 'yes' implied 'sem' */
if (!strcasecmp(meth, "default") || !strcasecmp(meth, "yes")) {
*mutexmech = APR_LOCK_DEFAULT;
}
#if APR_HAS_FCNTL_SERIALIZE
else if (!strcasecmp(meth, "fcntl") || !strcasecmp(meth, "file")) {
*mutexmech = APR_LOCK_FCNTL;
}
#endif
#if APR_HAS_FLOCK_SERIALIZE
else if (!strcasecmp(meth, "flock") || !strcasecmp(meth, "file")) {
*mutexmech = APR_LOCK_FLOCK;
}
#endif
#if APR_HAS_POSIXSEM_SERIALIZE
else if (!strcasecmp(meth, "posixsem") || !strcasecmp(meth, "sem")) {
*mutexmech = APR_LOCK_POSIXSEM;
/* Posix/SysV semaphores aren't file based, use the literal name
* if provided and fall back on APR's default if not. Today, APR
* will ignore it, but once supported it has an absurdly short limit.
*/
if (file) {
*mutexfile = apr_pstrdup(pool, file);
file = NULL;
}
}
#endif
#if APR_HAS_SYSVSEM_SERIALIZE
else if (!strcasecmp(meth, "sysvsem") || !strcasecmp(meth, "sem")) {
*mutexmech = APR_LOCK_SYSVSEM;
}
#endif
#if APR_HAS_PROC_PTHREAD_SERIALIZE
else if (!strcasecmp(meth, "pthread")) {
*mutexmech = APR_LOCK_PROC_PTHREAD;
}
#endif
else {
return APR_ENOTIMPL;
}
/* Unless the method above assumed responsibility for setting up
* mutexfile and NULLing out file, presume it is a file we
* are looking to use
*/
if (file) {
*mutexfile = ap_runtime_dir_relative(pool, file);
if (!*mutexfile) {
return APR_BADARG;
}
}
return APR_SUCCESS;
}
typedef struct {
apr_int32_t options;
int set;
int none;
int omit_pid;
apr_lockmech_e mech;
const char *dir;
} mutex_cfg_t;
/* hash is created the first time a module calls ap_mutex_register(),
* rather than attempting to be the REALLY_REALLY_FIRST pre-config
* hook; it is cleaned up when the associated pool goes away; assume
* pconf is the pool passed to ap_mutex_register()
*/
static apr_hash_t *mxcfg_by_type;
AP_DECLARE_NONSTD(void) ap_mutex_init(apr_pool_t *p)
{
mutex_cfg_t *def;
if (mxcfg_by_type) {
return;
}
mxcfg_by_type = apr_hash_make(p);
apr_pool_cleanup_register(p, &mxcfg_by_type, ap_pool_cleanup_set_null,
apr_pool_cleanup_null);
/* initialize default mutex configuration */
def = apr_pcalloc(p, sizeof *def);
def->mech = APR_LOCK_DEFAULT;
def->dir = ap_runtime_dir_relative(p, "");
apr_hash_set(mxcfg_by_type, "default", APR_HASH_KEY_STRING, def);
}
AP_DECLARE_NONSTD(const char *)ap_set_mutex(cmd_parms *cmd, void *dummy,
const char *arg)
{
apr_pool_t *p = cmd->pool;
apr_pool_t *ptemp = cmd->temp_pool;
const char **elt;
const char *mechdir;
int no_mutex = 0, omit_pid = 0;
apr_array_header_t *type_list;
apr_lockmech_e mech;
apr_status_t rv;
const char *mutexdir;
mutex_cfg_t *mxcfg;
const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
if (err != NULL) {
return err;
}
mechdir = ap_getword_conf(cmd->pool, &arg);
if (*mechdir == '\0') {
return "Mutex requires at least a mechanism argument ("
AP_ALL_AVAILABLE_MUTEXES_STRING ")";
}
rv = ap_parse_mutex(mechdir, p, &mech, &mutexdir);
if (rv == APR_ENOTIMPL) {
return apr_pstrcat(p, "Invalid Mutex argument ", mechdir,
" (" AP_ALL_AVAILABLE_MUTEXES_STRING ")", NULL);
}
else if (rv == APR_BADARG
|| (mutexdir && !ap_is_directory(ptemp, mutexdir))) {
return apr_pstrcat(p, "Invalid Mutex directory in argument ",
mechdir, NULL);
}
else if (rv == APR_ENOLOCK) { /* "none" */
no_mutex = 1;
}
/* "OmitPID" can appear at the end of the list, so build a list of
* mutex type names while looking for "OmitPID" (anywhere) or the end
*/
type_list = apr_array_make(cmd->pool, 4, sizeof(const char *));
while (*arg) {
const char *s = ap_getword_conf(cmd->pool, &arg);
if (!strcasecmp(s, "omitpid")) {
omit_pid = 1;
}
else {
const char **new_type = (const char **)apr_array_push(type_list);
*new_type = s;
}
}
if (apr_is_empty_array(type_list)) { /* no mutex type? assume "default" */
const char **new_type = (const char **)apr_array_push(type_list);
*new_type = "default";
}
while ((elt = (const char **)apr_array_pop(type_list)) != NULL) {
const char *type = *elt;
mxcfg = apr_hash_get(mxcfg_by_type, type, APR_HASH_KEY_STRING);
if (!mxcfg) {
return apr_psprintf(p, "Mutex type %s is not valid", type);
}
mxcfg->none = 0; /* in case that was the default */
mxcfg->omit_pid = omit_pid;
mxcfg->set = 1;
if (no_mutex) {
if (!(mxcfg->options & AP_MUTEX_ALLOW_NONE)) {
return apr_psprintf(p,
"None is not allowed for mutex type %s",
type);
}
mxcfg->none = 1;
}
else {
mxcfg->mech = mech;
if (mutexdir) { /* retain mutex default if not configured */
mxcfg->dir = mutexdir;
}
}
}
return NULL;
}
AP_DECLARE(apr_status_t) ap_mutex_register(apr_pool_t *pconf,
const char *type,
const char *default_dir,
apr_lockmech_e default_mech,
apr_int32_t options)
{
mutex_cfg_t *mxcfg = apr_pcalloc(pconf, sizeof *mxcfg);
if ((options & ~(AP_MUTEX_ALLOW_NONE | AP_MUTEX_DEFAULT_NONE))) {
return APR_EINVAL;
}
ap_mutex_init(pconf); /* in case this mod's pre-config ran before core's */
mxcfg->options = options;
if (options & AP_MUTEX_DEFAULT_NONE) {
mxcfg->none = 1;
}
mxcfg->dir = default_dir; /* usually NULL */
mxcfg->mech = default_mech; /* usually APR_LOCK_DEFAULT */
apr_hash_set(mxcfg_by_type, type, APR_HASH_KEY_STRING, mxcfg);
return APR_SUCCESS;
}
static int mutex_needs_file(apr_lockmech_e mech)
{
if (mech != APR_LOCK_FLOCK
&& mech != APR_LOCK_FCNTL
#if APR_USE_FLOCK_SERIALIZE || APR_USE_FCNTL_SERIALIZE
&& mech != APR_LOCK_DEFAULT
#endif
) {
return 0;
}
return 1;
}
static const char *get_mutex_filename(apr_pool_t *p, mutex_cfg_t *mxcfg,
const char *type,
const char *instance_id)
{
const char *pid_suffix = "";
if (!mutex_needs_file(mxcfg->mech)) {
return NULL;
}
#if HAVE_UNISTD_H
if (!mxcfg->omit_pid) {
pid_suffix = apr_psprintf(p, ".%" APR_PID_T_FMT, getpid());
}
#endif
return ap_runtime_dir_relative(p,
apr_pstrcat(p,
mxcfg->dir,
"/",
type,
instance_id ? "-" : "",
instance_id ? instance_id : "",
pid_suffix,
NULL));
}
static mutex_cfg_t *mxcfg_lookup(apr_pool_t *p, const char *type)
{
mutex_cfg_t *defcfg, *mxcfg, *newcfg;
defcfg = apr_hash_get(mxcfg_by_type, "default", APR_HASH_KEY_STRING);
/* MUST exist in table, or wasn't registered */
mxcfg = apr_hash_get(mxcfg_by_type, type, APR_HASH_KEY_STRING);
if (!mxcfg) {
return NULL;
}
/* order of precedence:
* 1. Mutex directive for this mutex
* 2. Mutex directive for "default"
* 3. Defaults for this mutex from ap_mutex_register()
* 4. Global defaults
*/
if (mxcfg->set) {
newcfg = mxcfg;
}
else if (defcfg->set) {
newcfg = defcfg;
}
else if (mxcfg->none || mxcfg->mech != APR_LOCK_DEFAULT) {
newcfg = mxcfg;
}
else {
newcfg = defcfg;
}
if (!newcfg->none && mutex_needs_file(newcfg->mech) && !newcfg->dir) {
/* a file-based mutex mechanism was configured, but
* without a mutex file directory; go back through
* the chain to find the directory, store in new
* mutex cfg structure
*/
newcfg = apr_pmemdup(p, newcfg, sizeof *newcfg);
/* !true if dir not already set: mxcfg->set && defcfg->dir */
if (defcfg->set && defcfg->dir) {
newcfg->dir = defcfg->dir;
}
else if (mxcfg->dir) {
newcfg->dir = mxcfg->dir;
}
else {
newcfg->dir = defcfg->dir;
}
}
return newcfg;
}
static void log_bad_create_options(server_rec *s, const char *type)
{
ap_log_error(APLOG_MARK, APLOG_EMERG, 0, s, APLOGNO(00021)
"Invalid options were specified when creating the %s mutex",
type);
}
static void log_unknown_type(server_rec *s, const char *type)
{
ap_log_error(APLOG_MARK, APLOG_EMERG, 0, s, APLOGNO(00022)
"Can't create mutex of unknown type %s", type);
}
static void log_create_failure(apr_status_t rv, server_rec *s, const char *type,
const char *fname)
{
ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s, APLOGNO(00023)
"Couldn't create the %s mutex %s%s%s", type,
fname ? "(file " : "",
fname ? fname : "",
fname ? ")" : "");
}
#ifdef AP_NEED_SET_MUTEX_PERMS
static void log_perms_failure(apr_status_t rv, server_rec *s, const char *type)
{
ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s, APLOGNO(00024)
"Couldn't set permissions on the %s mutex; "
"check User and Group directives",
type);
}
#endif
AP_DECLARE(apr_status_t) ap_global_mutex_create(apr_global_mutex_t **mutex,
const char **name,
const char *type,
const char *instance_id,
server_rec *s, apr_pool_t *p,
apr_int32_t options)
{
apr_status_t rv;
const char *fname;
mutex_cfg_t *mxcfg = mxcfg_lookup(p, type);
if (options) {
log_bad_create_options(s, type);
return APR_EINVAL;
}
if (!mxcfg) {
log_unknown_type(s, type);
return APR_EINVAL;
}
if (mxcfg->none) {
*mutex = NULL;
return APR_SUCCESS;
}
fname = get_mutex_filename(p, mxcfg, type, instance_id);
rv = apr_global_mutex_create(mutex, fname, mxcfg->mech, p);
if (rv != APR_SUCCESS) {
log_create_failure(rv, s, type, fname);
return rv;
}
if (name)
*name = fname;
#ifdef AP_NEED_SET_MUTEX_PERMS
rv = ap_unixd_set_global_mutex_perms(*mutex);
if (rv != APR_SUCCESS) {
log_perms_failure(rv, s, type);
}
#endif
return rv;
}
AP_DECLARE(apr_status_t) ap_proc_mutex_create(apr_proc_mutex_t **mutex,
const char **name,
const char *type,
const char *instance_id,
server_rec *s, apr_pool_t *p,
apr_int32_t options)
{
apr_status_t rv;
const char *fname;
mutex_cfg_t *mxcfg = mxcfg_lookup(p, type);
if (options) {
log_bad_create_options(s, type);
return APR_EINVAL;
}
if (!mxcfg) {
log_unknown_type(s, type);
return APR_EINVAL;
}
if (mxcfg->none) {
*mutex = NULL;
return APR_SUCCESS;
}
fname = get_mutex_filename(p, mxcfg, type, instance_id);
rv = apr_proc_mutex_create(mutex, fname, mxcfg->mech, p);
if (rv != APR_SUCCESS) {
log_create_failure(rv, s, type, fname);
return rv;
}
if (name)
*name = fname;
#ifdef AP_NEED_SET_MUTEX_PERMS
rv = ap_unixd_set_proc_mutex_perms(*mutex);
if (rv != APR_SUCCESS) {
log_perms_failure(rv, s, type);
}
#endif
return rv;
}
AP_CORE_DECLARE(void) ap_dump_mutexes(apr_pool_t *p, server_rec *s, apr_file_t *out)
{
apr_hash_index_t *idx;
mutex_cfg_t *defcfg = apr_hash_get(mxcfg_by_type, "default", APR_HASH_KEY_STRING);
for (idx = apr_hash_first(p, mxcfg_by_type); idx; idx = apr_hash_next(idx))
{
mutex_cfg_t *mxcfg;
const char *name, *mech;
const void *name_;
const char *dir = "";
apr_hash_this(idx, &name_, NULL, NULL);
name = name_;
mxcfg = mxcfg_lookup(p, name);
if (mxcfg == defcfg && strcmp(name, "default") != 0) {
apr_file_printf(out, "Mutex %s: using_defaults\n", name);
continue;
}
if (mxcfg->none) {
apr_file_printf(out, "Mutex %s: none\n", name);
continue;
}
switch (mxcfg->mech) {
case APR_LOCK_DEFAULT:
mech = "default";
break;
#if APR_HAS_FCNTL_SERIALIZE
case APR_LOCK_FCNTL:
mech = "fcntl";
break;
#endif
#if APR_HAS_FLOCK_SERIALIZE
case APR_LOCK_FLOCK:
mech = "flock";
break;
#endif
#if APR_HAS_POSIXSEM_SERIALIZE
case APR_LOCK_POSIXSEM:
mech = "posixsem";
break;
#endif
#if APR_HAS_SYSVSEM_SERIALIZE
case APR_LOCK_SYSVSEM:
mech = "sysvsem";
break;
#endif
#if APR_HAS_PROC_PTHREAD_SERIALIZE
case APR_LOCK_PROC_PTHREAD:
mech = "pthread";
break;
#endif
default:
ap_assert(0);
}
if (mxcfg->dir)
dir = ap_runtime_dir_relative(p, mxcfg->dir);
apr_file_printf(out, "Mutex %s: dir=\"%s\" mechanism=%s %s\n", name, dir, mech,
mxcfg->omit_pid ? "[OmitPid]" : "");
}
}
|