Plugin enumerator enumerates over loaded features, too
[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 /* require a registration function */
311 if (!reg ||
312 (reg->kind == FEATURE_REGISTER && reg->type != feature->type))
313 {
314 DBG1(DBG_LIB, "loading '%s' plugin feature %s failed: "
315 "invalid registration function", name, str);
316 free(str);
317 return FALSE;
318 }
319 break;
320 default:
321 break;
322 }
323 if (reg && reg->kind == FEATURE_CALLBACK)
324 {
325 if (!reg->cb.f(entry->plugin, feature, TRUE, reg->cb.data))
326 {
327 DBG1(DBG_LIB, "loading '%s' plugin feature %s with callback failed",
328 name, str);
329 free(str);
330 return FALSE;
331 }
332 }
333 else
334 {
335 switch (feature->type)
336 {
337 case FEATURE_CRYPTER:
338 lib->crypto->add_crypter(lib->crypto, feature->crypter.alg,
339 name, reg->reg.f);
340 break;
341 case FEATURE_SIGNER:
342 lib->crypto->add_signer(lib->crypto, feature->signer,
343 name, reg->reg.f);
344 break;
345 case FEATURE_HASHER:
346 lib->crypto->add_hasher(lib->crypto, feature->hasher,
347 name, reg->reg.f);
348 break;
349 case FEATURE_PRF:
350 lib->crypto->add_prf(lib->crypto, feature->prf,
351 name, reg->reg.f);
352 break;
353 case FEATURE_DH:
354 lib->crypto->add_dh(lib->crypto, feature->dh_group,
355 name, reg->reg.f);
356 break;
357 case FEATURE_RNG:
358 lib->crypto->add_rng(lib->crypto, feature->rng_quality,
359 name, reg->reg.f);
360 break;
361 case FEATURE_PRIVKEY:
362 case FEATURE_PRIVKEY_GEN:
363 lib->creds->add_builder(lib->creds, CRED_PRIVATE_KEY,
364 feature->privkey, reg->reg.final, reg->reg.f);
365 break;
366 case FEATURE_PUBKEY:
367 lib->creds->add_builder(lib->creds, CRED_PUBLIC_KEY,
368 feature->pubkey, reg->reg.final, reg->reg.f);
369 break;
370 case FEATURE_CERT_DECODE:
371 case FEATURE_CERT_ENCODE:
372 lib->creds->add_builder(lib->creds, CRED_CERTIFICATE,
373 feature->cert, reg->reg.final, reg->reg.f);
374 break;
375 default:
376 break;
377 }
378 }
379 DBG2(DBG_LIB, "loaded '%s' plugin feature %s", name, str);
380 free(str);
381 entry->loaded->insert_last(entry->loaded, feature);
382 return TRUE;
383 }
384
385 /**
386 * Load plugin features in correct order
387 */
388 static int load_features(private_plugin_loader_t *this, bool soft, bool report)
389 {
390 enumerator_t *enumerator;
391 plugin_feature_t *features, *reg = NULL;
392 plugin_entry_t *entry;
393 int count, i, loaded = 0;
394 char *name;
395
396 enumerator = this->plugins->create_enumerator(this->plugins);
397 while (enumerator->enumerate(enumerator, &entry))
398 {
399 if (!entry->plugin->get_features)
400 { /* feature interface not supported */
401 continue;
402 }
403 name = entry->plugin->get_name(entry->plugin);
404 count = entry->plugin->get_features(entry->plugin, &features);
405 for (i = 0; i < count; i++)
406 {
407 switch (features[i].kind)
408 {
409 case FEATURE_PROVIDE:
410 if (!feature_loaded(this, entry, &features[i]) &&
411 dependencies_satisfied(this, name, soft, report,
412 &features[i], count - i) &&
413 load_feature(this, entry, name, &features[i], reg))
414 {
415 loaded++;
416 }
417 break;
418 case FEATURE_REGISTER:
419 case FEATURE_CALLBACK:
420 reg = &features[i];
421 break;
422 default:
423 break;
424 }
425 }
426 }
427 enumerator->destroy(enumerator);
428 return loaded;
429 }
430
431 METHOD(plugin_loader_t, load_plugins, bool,
432 private_plugin_loader_t *this, char *path, char *list)
433 {
434 enumerator_t *enumerator;
435 char *token;
436 bool critical_failed = FALSE;
437
438 if (path == NULL)
439 {
440 path = PLUGINDIR;
441 }
442
443 enumerator = enumerator_create_token(list, " ", " ");
444 while (!critical_failed && enumerator->enumerate(enumerator, &token))
445 {
446 bool critical = FALSE;
447 char file[PATH_MAX];
448 int len;
449
450 token = strdup(token);
451 len = strlen(token);
452 if (token[len-1] == '!')
453 {
454 critical = TRUE;
455 token[len-1] = '\0';
456 }
457 if (plugin_loaded(this, token))
458 {
459 free(token);
460 continue;
461 }
462 if (snprintf(file, sizeof(file), "%s/libstrongswan-%s.so",
463 path, token) >= sizeof(file))
464 {
465 return NULL;
466 }
467 if (!load_plugin(this, token, file) && critical)
468 {
469 critical_failed = TRUE;
470 DBG1(DBG_LIB, "loading critical plugin '%s' failed", token);
471 }
472 free(token);
473 }
474 enumerator->destroy(enumerator);
475 if (!critical_failed)
476 {
477 while (load_features(this, TRUE, FALSE))
478 {
479 /* try load new features until we don't get new ones */
480 }
481 while (load_features(this, FALSE, FALSE))
482 {
483 /* second round, ignoring soft dependencies */
484 }
485 /* report missing dependencies */
486 load_features(this, FALSE, TRUE);
487 }
488 return !critical_failed;
489 }
490
491 METHOD(plugin_loader_t, unload, void,
492 private_plugin_loader_t *this)
493 {
494 plugin_entry_t *entry;
495
496 /* unload plugins in reverse order */
497 while (this->plugins->remove_last(this->plugins,
498 (void**)&entry) == SUCCESS)
499 {
500 if (lib->leak_detective)
501 { /* keep handle to report leaks properly */
502 entry->handle = NULL;
503 }
504 plugin_entry_destroy(entry);
505 }
506 }
507
508 /**
509 * Reload a plugin by name, NULL for all
510 */
511 static u_int reload_by_name(private_plugin_loader_t *this, char *name)
512 {
513 u_int reloaded = 0;
514 enumerator_t *enumerator;
515 plugin_t *plugin;
516
517 enumerator = create_plugin_enumerator(this);
518 while (enumerator->enumerate(enumerator, &plugin, NULL))
519 {
520 if (name == NULL || streq(name, plugin->get_name(plugin)))
521 {
522 if (plugin->reload && plugin->reload(plugin))
523 {
524 DBG2(DBG_LIB, "reloaded configuration of '%s' plugin",
525 plugin->get_name(plugin));
526 reloaded++;
527 }
528 }
529 }
530 enumerator->destroy(enumerator);
531 return reloaded;
532 }
533
534 METHOD(plugin_loader_t, reload, u_int,
535 private_plugin_loader_t *this, char *list)
536 {
537 u_int reloaded = 0;
538 enumerator_t *enumerator;
539 char *name;
540
541 if (list == NULL)
542 {
543 return reload_by_name(this, NULL);
544 }
545 enumerator = enumerator_create_token(list, " ", "");
546 while (enumerator->enumerate(enumerator, &name))
547 {
548 reloaded += reload_by_name(this, name);
549 }
550 enumerator->destroy(enumerator);
551 return reloaded;
552 }
553
554 METHOD(plugin_loader_t, destroy, void,
555 private_plugin_loader_t *this)
556 {
557 unload(this);
558 this->plugins->destroy(this->plugins);
559 free(this);
560 }
561
562 /*
563 * see header file
564 */
565 plugin_loader_t *plugin_loader_create()
566 {
567 private_plugin_loader_t *this;
568
569 INIT(this,
570 .public = {
571 .load = _load_plugins,
572 .reload = _reload,
573 .unload = _unload,
574 .create_plugin_enumerator = _create_plugin_enumerator,
575 .destroy = _destroy,
576 },
577 .plugins = linked_list_create(),
578 );
579
580 return &this->public;
581 }
582