Added database and fetcher plugin features
[strongswan.git] / src / libstrongswan / plugins / plugin_loader.c
1 /*
2 * Copyright (C) 2010 Tobias Brunner
3 * Copyright (C) 2007 Martin Willi
4 * Hochschule fuer Technik Rapperswil
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; either version 2 of the License, or (at your
9 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * for more details.
15 */
16
17 #define _GNU_SOURCE
18 #include "plugin_loader.h"
19
20 #include <string.h>
21 #include <dlfcn.h>
22 #include <limits.h>
23 #include <stdio.h>
24
25 #include <debug.h>
26 #include <library.h>
27 #include <integrity_checker.h>
28 #include <utils/linked_list.h>
29 #include <plugins/plugin.h>
30
31 typedef struct private_plugin_loader_t private_plugin_loader_t;
32 typedef struct plugin_entry_t plugin_entry_t;
33
34 /**
35 * private data of plugin_loader
36 */
37 struct private_plugin_loader_t {
38
39 /**
40 * public functions
41 */
42 plugin_loader_t public;
43
44 /**
45 * List of plugins, as plugin_entry_t
46 */
47 linked_list_t *plugins;
48 };
49
50 /**
51 * Entry for a plugin
52 */
53 struct plugin_entry_t {
54
55 /**
56 * Plugin instance
57 */
58 plugin_t *plugin;
59
60 /**
61 * dlopen handle, if in separate lib
62 */
63 void *handle;
64
65 /**
66 * List of loaded features
67 */
68 linked_list_t *loaded;
69 };
70
71 /**
72 * Destroy a plugin entry
73 */
74 static void plugin_entry_destroy(plugin_entry_t *entry)
75 {
76 DESTROY_IF(entry->plugin);
77 if (entry->handle)
78 {
79 dlclose(entry->handle);
80 }
81 entry->loaded->destroy(entry->loaded);
82 free(entry);
83 }
84
85 /**
86 * create a plugin
87 * returns: NOT_FOUND, if the constructor was not found
88 * FAILED, if the plugin could not be constructed
89 */
90 static status_t create_plugin(private_plugin_loader_t *this, void *handle,
91 char *name, bool integrity, plugin_entry_t **entry)
92 {
93 char create[128];
94 plugin_t *plugin;
95 plugin_constructor_t constructor;
96
97 if (snprintf(create, sizeof(create), "%s_plugin_create",
98 name) >= sizeof(create))
99 {
100 return FAILED;
101 }
102 translate(create, "-", "_");
103 constructor = dlsym(handle, create);
104 if (constructor == NULL)
105 {
106 return NOT_FOUND;
107 }
108 if (integrity && lib->integrity)
109 {
110 if (!lib->integrity->check_segment(lib->integrity, name, constructor))
111 {
112 DBG1(DBG_LIB, "plugin '%s': failed segment integrity test", name);
113 return FAILED;
114 }
115 DBG1(DBG_LIB, "plugin '%s': passed file and segment integrity tests",
116 name);
117 }
118 plugin = constructor();
119 if (plugin == NULL)
120 {
121 DBG1(DBG_LIB, "plugin '%s': failed to load - %s returned NULL", name,
122 create);
123 return FAILED;
124 }
125 INIT(*entry,
126 .plugin = plugin,
127 .loaded = linked_list_create(),
128 );
129 DBG2(DBG_LIB, "plugin '%s': loaded successfully", name);
130 return SUCCESS;
131 }
132
133 /**
134 * load a single plugin
135 */
136 static bool load_plugin(private_plugin_loader_t *this, char *name, char *file)
137 {
138 plugin_entry_t *entry;
139 void *handle;
140
141 switch (create_plugin(this, RTLD_DEFAULT, name, FALSE, &entry))
142 {
143 case SUCCESS:
144 this->plugins->insert_last(this->plugins, entry);
145 return TRUE;
146 case NOT_FOUND:
147 /* try to load the plugin from a file */
148 break;
149 default:
150 return FALSE;
151 }
152 if (lib->integrity)
153 {
154 if (!lib->integrity->check_file(lib->integrity, name, file))
155 {
156 DBG1(DBG_LIB, "plugin '%s': failed file integrity test of '%s'",
157 name, file);
158 return FALSE;
159 }
160 }
161 handle = dlopen(file, RTLD_LAZY);
162 if (handle == NULL)
163 {
164 DBG1(DBG_LIB, "plugin '%s' failed to load: %s", name, dlerror());
165 return FALSE;
166 }
167 if (create_plugin(this, handle, name, TRUE, &entry) != SUCCESS)
168 {
169 dlclose(handle);
170 return FALSE;
171 }
172 entry->handle = handle;
173 this->plugins->insert_last(this->plugins, entry);
174 return TRUE;
175 }
176
177 /**
178 * Convert enumerated entries to plugin_t
179 */
180 static bool plugin_filter(void *null, plugin_entry_t **entry, plugin_t **plugin,
181 void *in, linked_list_t **list)
182 {
183 *plugin = (*entry)->plugin;
184 if (list)
185 {
186 *list = (*entry)->loaded;
187 }
188 return TRUE;
189 }
190
191 METHOD(plugin_loader_t, create_plugin_enumerator, enumerator_t*,
192 private_plugin_loader_t *this)
193 {
194 return enumerator_create_filter(
195 this->plugins->create_enumerator(this->plugins),
196 (void*)plugin_filter, NULL, NULL);
197 }
198
199 /**
200 * Check if a plugin is already loaded
201 */
202 static bool plugin_loaded(private_plugin_loader_t *this, char *name)
203 {
204 enumerator_t *enumerator;
205 bool found = FALSE;
206 plugin_t *plugin;
207
208 enumerator = create_plugin_enumerator(this);
209 while (enumerator->enumerate(enumerator, &plugin, NULL))
210 {
211 if (streq(plugin->get_name(plugin), name))
212 {
213 found = TRUE;
214 break;
215 }
216 }
217 enumerator->destroy(enumerator);
218 return found;
219 }
220
221 /**
222 * Check if a feature of a plugin is already loaded
223 */
224 static bool feature_loaded(private_plugin_loader_t *this, plugin_entry_t *entry,
225 plugin_feature_t *feature)
226 {
227 return entry->loaded->find_first(entry->loaded, NULL,
228 (void**)&feature) == SUCCESS;
229 }
230
231 /**
232 * Check if dependencies are satisfied
233 */
234
235 static bool dependencies_satisfied(private_plugin_loader_t *this, char *name,
236 bool soft, bool report, plugin_feature_t *features, int count)
237 {
238 int i;
239
240 /* first entry is provided feature, followed by dependencies */
241 for (i = 1; i < count; i++)
242 {
243 enumerator_t *entries, *loaded;
244 plugin_feature_t *feature;
245 plugin_entry_t *entry;
246 bool found = FALSE;
247
248 if (features[i].kind != FEATURE_DEPENDS &&
249 features[i].kind != FEATURE_SDEPEND)
250 { /* end of dependencies */
251 break;
252 }
253 entries = this->plugins->create_enumerator(this->plugins);
254 while (entries->enumerate(entries, &entry))
255 {
256 loaded = entry->loaded->create_enumerator(entry->loaded);
257 while (loaded->enumerate(loaded, &feature))
258 {
259 if (plugin_feature_matches(&features[i], feature))
260 {
261 found = TRUE;
262 break;
263 }
264 }
265 loaded->destroy(loaded);
266 }
267 entries->destroy(entries);
268
269 if (!found && !(features[i].kind == FEATURE_SDEPEND && !soft))
270 {
271 if (report)
272 {
273 char *provide, *depend;
274
275 provide = plugin_feature_get_string(&features[0]);
276 depend = plugin_feature_get_string(&features[i]);
277 DBG1(DBG_LIB, "feature %s in '%s' plugin has unsatisfied "
278 "dependency: %s", provide, name, depend);
279 free(provide);
280 free(depend);
281 }
282 return FALSE;
283 }
284 }
285 return TRUE;
286 }
287
288 /**
289 * Load a plugin feature
290 */
291 static bool load_feature(private_plugin_loader_t *this, plugin_entry_t *entry,
292 char *name, plugin_feature_t *feature, plugin_feature_t *reg)
293 {
294 char *str;
295
296 str = plugin_feature_get_string(feature);
297 switch (feature->type)
298 {
299 case FEATURE_CRYPTER:
300 case FEATURE_SIGNER:
301 case FEATURE_HASHER:
302 case FEATURE_PRF:
303 case FEATURE_DH:
304 case FEATURE_RNG:
305 case FEATURE_PRIVKEY:
306 case FEATURE_PRIVKEY_GEN:
307 case FEATURE_PUBKEY:
308 case FEATURE_CERT_DECODE:
309 case FEATURE_CERT_ENCODE:
310 case FEATURE_DATABASE:
311 case FEATURE_FETCHER:
312 /* require a registration function */
313 if (!reg ||
314 (reg->kind == FEATURE_REGISTER && reg->type != feature->type))
315 {
316 DBG1(DBG_LIB, "loading '%s' plugin feature %s failed: "
317 "invalid registration function", name, str);
318 free(str);
319 return FALSE;
320 }
321 break;
322 default:
323 break;
324 }
325 if (reg && reg->kind == FEATURE_CALLBACK)
326 {
327 if (!reg->cb.f(entry->plugin, feature, TRUE, reg->cb.data))
328 {
329 DBG1(DBG_LIB, "loading '%s' plugin feature %s with callback failed",
330 name, str);
331 free(str);
332 return FALSE;
333 }
334 }
335 else
336 {
337 switch (feature->type)
338 {
339 case FEATURE_CRYPTER:
340 lib->crypto->add_crypter(lib->crypto, feature->crypter.alg,
341 name, reg->reg.f);
342 break;
343 case FEATURE_SIGNER:
344 lib->crypto->add_signer(lib->crypto, feature->signer,
345 name, reg->reg.f);
346 break;
347 case FEATURE_HASHER:
348 lib->crypto->add_hasher(lib->crypto, feature->hasher,
349 name, reg->reg.f);
350 break;
351 case FEATURE_PRF:
352 lib->crypto->add_prf(lib->crypto, feature->prf,
353 name, reg->reg.f);
354 break;
355 case FEATURE_DH:
356 lib->crypto->add_dh(lib->crypto, feature->dh_group,
357 name, reg->reg.f);
358 break;
359 case FEATURE_RNG:
360 lib->crypto->add_rng(lib->crypto, feature->rng_quality,
361 name, reg->reg.f);
362 break;
363 case FEATURE_PRIVKEY:
364 case FEATURE_PRIVKEY_GEN:
365 lib->creds->add_builder(lib->creds, CRED_PRIVATE_KEY,
366 feature->privkey, reg->reg.final, reg->reg.f);
367 break;
368 case FEATURE_PUBKEY:
369 lib->creds->add_builder(lib->creds, CRED_PUBLIC_KEY,
370 feature->pubkey, reg->reg.final, reg->reg.f);
371 break;
372 case FEATURE_CERT_DECODE:
373 case FEATURE_CERT_ENCODE:
374 lib->creds->add_builder(lib->creds, CRED_CERTIFICATE,
375 feature->cert, reg->reg.final, reg->reg.f);
376 break;
377 case FEATURE_DATABASE:
378 lib->db->add_database(lib->db, reg->reg.f);
379 break;
380 case FEATURE_FETCHER:
381 lib->fetcher->add_fetcher(lib->fetcher, reg->reg.f,
382 feature->fetcher);
383 break;
384 default:
385 break;
386 }
387 }
388 DBG2(DBG_LIB, "loaded '%s' plugin feature %s", name, str);
389 free(str);
390 entry->loaded->insert_last(entry->loaded, feature);
391 return TRUE;
392 }
393
394 /**
395 * Load plugin features in correct order
396 */
397 static int load_features(private_plugin_loader_t *this, bool soft, bool report)
398 {
399 enumerator_t *enumerator;
400 plugin_feature_t *features, *reg = NULL;
401 plugin_entry_t *entry;
402 int count, i, loaded = 0;
403 char *name;
404
405 enumerator = this->plugins->create_enumerator(this->plugins);
406 while (enumerator->enumerate(enumerator, &entry))
407 {
408 if (!entry->plugin->get_features)
409 { /* feature interface not supported */
410 continue;
411 }
412 name = entry->plugin->get_name(entry->plugin);
413 count = entry->plugin->get_features(entry->plugin, &features);
414 for (i = 0; i < count; i++)
415 {
416 switch (features[i].kind)
417 {
418 case FEATURE_PROVIDE:
419 if (!feature_loaded(this, entry, &features[i]) &&
420 dependencies_satisfied(this, name, soft, report,
421 &features[i], count - i) &&
422 load_feature(this, entry, name, &features[i], reg))
423 {
424 loaded++;
425 }
426 break;
427 case FEATURE_REGISTER:
428 case FEATURE_CALLBACK:
429 reg = &features[i];
430 break;
431 default:
432 break;
433 }
434 }
435 }
436 enumerator->destroy(enumerator);
437 return loaded;
438 }
439
440 METHOD(plugin_loader_t, load_plugins, bool,
441 private_plugin_loader_t *this, char *path, char *list)
442 {
443 enumerator_t *enumerator;
444 char *token;
445 bool critical_failed = FALSE;
446
447 if (path == NULL)
448 {
449 path = PLUGINDIR;
450 }
451
452 enumerator = enumerator_create_token(list, " ", " ");
453 while (!critical_failed && enumerator->enumerate(enumerator, &token))
454 {
455 bool critical = FALSE;
456 char file[PATH_MAX];
457 int len;
458
459 token = strdup(token);
460 len = strlen(token);
461 if (token[len-1] == '!')
462 {
463 critical = TRUE;
464 token[len-1] = '\0';
465 }
466 if (plugin_loaded(this, token))
467 {
468 free(token);
469 continue;
470 }
471 if (snprintf(file, sizeof(file), "%s/libstrongswan-%s.so",
472 path, token) >= sizeof(file))
473 {
474 return NULL;
475 }
476 if (!load_plugin(this, token, file) && critical)
477 {
478 critical_failed = TRUE;
479 DBG1(DBG_LIB, "loading critical plugin '%s' failed", token);
480 }
481 free(token);
482 }
483 enumerator->destroy(enumerator);
484 if (!critical_failed)
485 {
486 while (load_features(this, TRUE, FALSE))
487 {
488 /* try load new features until we don't get new ones */
489 }
490 while (load_features(this, FALSE, FALSE))
491 {
492 /* second round, ignoring soft dependencies */
493 }
494 /* report missing dependencies */
495 load_features(this, FALSE, TRUE);
496 }
497 return !critical_failed;
498 }
499
500 METHOD(plugin_loader_t, unload, void,
501 private_plugin_loader_t *this)
502 {
503 plugin_entry_t *entry;
504
505 /* unload plugins in reverse order */
506 while (this->plugins->remove_last(this->plugins,
507 (void**)&entry) == SUCCESS)
508 {
509 if (lib->leak_detective)
510 { /* keep handle to report leaks properly */
511 entry->handle = NULL;
512 }
513 plugin_entry_destroy(entry);
514 }
515 }
516
517 /**
518 * Reload a plugin by name, NULL for all
519 */
520 static u_int reload_by_name(private_plugin_loader_t *this, char *name)
521 {
522 u_int reloaded = 0;
523 enumerator_t *enumerator;
524 plugin_t *plugin;
525
526 enumerator = create_plugin_enumerator(this);
527 while (enumerator->enumerate(enumerator, &plugin, NULL))
528 {
529 if (name == NULL || streq(name, plugin->get_name(plugin)))
530 {
531 if (plugin->reload && plugin->reload(plugin))
532 {
533 DBG2(DBG_LIB, "reloaded configuration of '%s' plugin",
534 plugin->get_name(plugin));
535 reloaded++;
536 }
537 }
538 }
539 enumerator->destroy(enumerator);
540 return reloaded;
541 }
542
543 METHOD(plugin_loader_t, reload, u_int,
544 private_plugin_loader_t *this, char *list)
545 {
546 u_int reloaded = 0;
547 enumerator_t *enumerator;
548 char *name;
549
550 if (list == NULL)
551 {
552 return reload_by_name(this, NULL);
553 }
554 enumerator = enumerator_create_token(list, " ", "");
555 while (enumerator->enumerate(enumerator, &name))
556 {
557 reloaded += reload_by_name(this, name);
558 }
559 enumerator->destroy(enumerator);
560 return reloaded;
561 }
562
563 METHOD(plugin_loader_t, destroy, void,
564 private_plugin_loader_t *this)
565 {
566 unload(this);
567 this->plugins->destroy(this->plugins);
568 free(this);
569 }
570
571 /*
572 * see header file
573 */
574 plugin_loader_t *plugin_loader_create()
575 {
576 private_plugin_loader_t *this;
577
578 INIT(this,
579 .public = {
580 .load = _load_plugins,
581 .reload = _reload,
582 .unload = _unload,
583 .create_plugin_enumerator = _create_plugin_enumerator,
584 .destroy = _destroy,
585 },
586 .plugins = linked_list_create(),
587 );
588
589 return &this->public;
590 }
591