1 /* $OpenBSD: conf_mod.c,v 1.25 2014/07/22 02:21:20 beck Exp $ */
2 /* Written by Stephen Henson (steve@openssl.org) for the OpenSSL
3  * project 2001.
4  */
5 /* ====================================================================
6  * Copyright (c) 2001 The OpenSSL Project.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in
17  *    the documentation and/or other materials provided with the
18  *    distribution.
19  *
20  * 3. All advertising materials mentioning features or use of this
21  *    software must display the following acknowledgment:
22  *    "This product includes software developed by the OpenSSL Project
23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24  *
25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26  *    endorse or promote products derived from this software without
27  *    prior written permission. For written permission, please contact
28  *    licensing@OpenSSL.org.
29  *
30  * 5. Products derived from this software may not be called "OpenSSL"
31  *    nor may "OpenSSL" appear in their names without prior written
32  *    permission of the OpenSSL Project.
33  *
34  * 6. Redistributions of any form whatsoever must retain the following
35  *    acknowledgment:
36  *    "This product includes software developed by the OpenSSL Project
37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38  *
39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50  * OF THE POSSIBILITY OF SUCH DAMAGE.
51  * ====================================================================
52  *
53  * This product includes cryptographic software written by Eric Young
54  * (eay@cryptsoft.com).  This product includes software written by Tim
55  * Hudson (tjh@cryptsoft.com).
56  *
57  */
58 
59 #include <ctype.h>
60 #include <stdio.h>
61 #include <string.h>
62 #include <unistd.h>
63 
64 #include <openssl/conf.h>
65 #include <openssl/crypto.h>
66 #include <openssl/dso.h>
67 #include <openssl/err.h>
68 #include <openssl/x509.h>
69 
70 #define DSO_mod_init_name "OPENSSL_init"
71 #define DSO_mod_finish_name "OPENSSL_finish"
72 
73 /* This structure contains a data about supported modules.
74  * entries in this table correspond to either dynamic or
75  * static modules.
76  */
77 
78 struct conf_module_st {
79 	/* DSO of this module or NULL if static */
80 	DSO *dso;
81 	/* Name of the module */
82 	char *name;
83 	/* Init function */
84 	conf_init_func *init;
85 	/* Finish function */
86 	conf_finish_func *finish;
87 	/* Number of successfully initialized modules */
88 	int links;
89 	void *usr_data;
90 };
91 
92 
93 /* This structure contains information about modules that have been
94  * successfully initialized. There may be more than one entry for a
95  * given module.
96  */
97 
98 struct conf_imodule_st {
99 	CONF_MODULE *pmod;
100 	char *name;
101 	char *value;
102 	unsigned long flags;
103 	void *usr_data;
104 };
105 
106 static STACK_OF(CONF_MODULE) *supported_modules = NULL;
107 static STACK_OF(CONF_IMODULE) *initialized_modules = NULL;
108 
109 static void module_free(CONF_MODULE *md);
110 static void module_finish(CONF_IMODULE *imod);
111 static int module_run(const CONF *cnf, char *name, char *value,
112     unsigned long flags);
113 static CONF_MODULE *module_add(DSO *dso, const char *name,
114     conf_init_func *ifunc, conf_finish_func *ffunc);
115 static CONF_MODULE *module_find(char *name);
116 static int module_init(CONF_MODULE *pmod, char *name, char *value,
117     const CONF *cnf);
118 static CONF_MODULE *module_load_dso(const CONF *cnf, char *name, char *value,
119     unsigned long flags);
120 
121 /* Main function: load modules from a CONF structure */
122 
123 int
124 CONF_modules_load(const CONF *cnf, const char *appname, unsigned long flags)
125 {
126 	STACK_OF(CONF_VALUE) *values;
127 	CONF_VALUE *vl;
128 	char *vsection = NULL;
129 
130 	int ret, i;
131 
132 	if (!cnf)
133 		return 1;
134 
135 	if (appname)
136 		vsection = NCONF_get_string(cnf, NULL, appname);
137 
138 	if (!appname || (!vsection && (flags & CONF_MFLAGS_DEFAULT_SECTION)))
139 		vsection = NCONF_get_string(cnf, NULL, "openssl_conf");
140 
141 	if (!vsection) {
142 		ERR_clear_error();
143 		return 1;
144 	}
145 
146 	values = NCONF_get_section(cnf, vsection);
147 
148 	if (!values)
149 		return 0;
150 
151 	for (i = 0; i < sk_CONF_VALUE_num(values); i++) {
152 		vl = sk_CONF_VALUE_value(values, i);
153 		ret = module_run(cnf, vl->name, vl->value, flags);
154 		if (ret <= 0)
155 			if (!(flags & CONF_MFLAGS_IGNORE_ERRORS))
156 				return ret;
157 	}
158 
159 	return 1;
160 }
161 
162 int
163 CONF_modules_load_file(const char *filename, const char *appname,
164     unsigned long flags)
165 {
166 	char *file = NULL;
167 	CONF *conf = NULL;
168 	int ret = 0;
169 	conf = NCONF_new(NULL);
170 	if (!conf)
171 		goto err;
172 
173 	if (filename == NULL) {
174 		file = CONF_get1_default_config_file();
175 		if (!file)
176 			goto err;
177 	} else
178 		file = (char *)filename;
179 
180 	if (NCONF_load(conf, file, NULL) <= 0) {
181 		if ((flags & CONF_MFLAGS_IGNORE_MISSING_FILE) &&
182 		    (ERR_GET_REASON(ERR_peek_last_error()) ==
183 		    CONF_R_NO_SUCH_FILE)) {
184 			ERR_clear_error();
185 			ret = 1;
186 		}
187 		goto err;
188 	}
189 
190 	ret = CONF_modules_load(conf, appname, flags);
191 
192 err:
193 	if (filename == NULL)
194 		free(file);
195 	NCONF_free(conf);
196 
197 	return ret;
198 }
199 
200 static int
201 module_run(const CONF *cnf, char *name, char *value, unsigned long flags)
202 {
203 	CONF_MODULE *md;
204 	int ret;
205 
206 	md = module_find(name);
207 
208 	/* Module not found: try to load DSO */
209 	if (!md && !(flags & CONF_MFLAGS_NO_DSO))
210 		md = module_load_dso(cnf, name, value, flags);
211 
212 	if (!md) {
213 		if (!(flags & CONF_MFLAGS_SILENT)) {
214 			CONFerr(CONF_F_MODULE_RUN, CONF_R_UNKNOWN_MODULE_NAME);
215 			ERR_asprintf_error_data("module=%s", name);
216 		}
217 		return -1;
218 	}
219 
220 	ret = module_init(md, name, value, cnf);
221 
222 	if (ret <= 0) {
223 		if (!(flags & CONF_MFLAGS_SILENT)) {
224 			CONFerr(CONF_F_MODULE_RUN,
225 			    CONF_R_MODULE_INITIALIZATION_ERROR);
226 			ERR_asprintf_error_data
227 			    ("module=%s, value=%s, retcode=%-8d",
228 			    name, value, ret);
229 		}
230 	}
231 
232 	return ret;
233 }
234 
235 /* Load a module from a DSO */
236 static CONF_MODULE *
237 module_load_dso(const CONF *cnf, char *name, char *value, unsigned long flags)
238 {
239 	DSO *dso = NULL;
240 	conf_init_func *ifunc;
241 	conf_finish_func *ffunc;
242 	char *path = NULL;
243 	int errcode = 0;
244 	CONF_MODULE *md;
245 
246 	/* Look for alternative path in module section */
247 	path = NCONF_get_string(cnf, value, "path");
248 	if (!path) {
249 		ERR_clear_error();
250 		path = name;
251 	}
252 	dso = DSO_load(NULL, path, NULL, 0);
253 	if (!dso) {
254 		errcode = CONF_R_ERROR_LOADING_DSO;
255 		goto err;
256 	}
257 	ifunc = (conf_init_func *)DSO_bind_func(dso, DSO_mod_init_name);
258 	if (!ifunc) {
259 		errcode = CONF_R_MISSING_INIT_FUNCTION;
260 		goto err;
261 	}
262 	ffunc = (conf_finish_func *)DSO_bind_func(dso, DSO_mod_finish_name);
263 	/* All OK, add module */
264 	md = module_add(dso, name, ifunc, ffunc);
265 
266 	if (!md)
267 		goto err;
268 
269 	return md;
270 
271 err:
272 	if (dso)
273 		DSO_free(dso);
274 	CONFerr(CONF_F_MODULE_LOAD_DSO, errcode);
275 	ERR_asprintf_error_data("module=%s, path=%s", name, path);
276 	return NULL;
277 }
278 
279 /* add module to list */
280 static CONF_MODULE *
281 module_add(DSO *dso, const char *name, conf_init_func *ifunc,
282     conf_finish_func *ffunc)
283 {
284 	CONF_MODULE *tmod = NULL;
285 
286 	if (name == NULL)
287 		return NULL;
288 	if (supported_modules == NULL)
289 		supported_modules = sk_CONF_MODULE_new_null();
290 	if (supported_modules == NULL)
291 		return NULL;
292 	tmod = malloc(sizeof(CONF_MODULE));
293 	if (tmod == NULL)
294 		return NULL;
295 
296 	tmod->dso = dso;
297 	tmod->name = strdup(name);
298 	tmod->init = ifunc;
299 	tmod->finish = ffunc;
300 	tmod->links = 0;
301 
302 	if (!sk_CONF_MODULE_push(supported_modules, tmod)) {
303 		free(tmod);
304 		return NULL;
305 	}
306 
307 	return tmod;
308 }
309 
310 /* Find a module from the list. We allow module names of the
311  * form modname.XXXX to just search for modname to allow the
312  * same module to be initialized more than once.
313  */
314 
315 static CONF_MODULE *
316 module_find(char *name)
317 {
318 	CONF_MODULE *tmod;
319 	int i, nchar;
320 	char *p;
321 
322 	p = strrchr(name, '.');
323 
324 	if (p)
325 		nchar = p - name;
326 	else
327 		nchar = strlen(name);
328 
329 	for (i = 0; i < sk_CONF_MODULE_num(supported_modules); i++) {
330 		tmod = sk_CONF_MODULE_value(supported_modules, i);
331 		if (!strncmp(tmod->name, name, nchar))
332 			return tmod;
333 	}
334 
335 	return NULL;
336 }
337 
338 /* initialize a module */
339 static int
340 module_init(CONF_MODULE *pmod, char *name, char *value, const CONF *cnf)
341 {
342 	int ret = 1;
343 	int init_called = 0;
344 	CONF_IMODULE *imod = NULL;
345 
346 	/* Otherwise add initialized module to list */
347 	imod = malloc(sizeof(CONF_IMODULE));
348 	if (!imod)
349 		goto err;
350 
351 	imod->pmod = pmod;
352 	imod->name = name ? strdup(name) : NULL;
353 	imod->value = value ? strdup(value) : NULL;
354 	imod->usr_data = NULL;
355 
356 	if (!imod->name || !imod->value)
357 		goto memerr;
358 
359 	/* Try to initialize module */
360 	if (pmod->init) {
361 		ret = pmod->init(imod, cnf);
362 		init_called = 1;
363 		/* Error occurred, exit */
364 		if (ret <= 0)
365 			goto err;
366 	}
367 
368 	if (initialized_modules == NULL) {
369 		initialized_modules = sk_CONF_IMODULE_new_null();
370 		if (!initialized_modules) {
371 			CONFerr(CONF_F_MODULE_INIT, ERR_R_MALLOC_FAILURE);
372 			goto err;
373 		}
374 	}
375 
376 	if (!sk_CONF_IMODULE_push(initialized_modules, imod)) {
377 		CONFerr(CONF_F_MODULE_INIT, ERR_R_MALLOC_FAILURE);
378 		goto err;
379 	}
380 
381 	pmod->links++;
382 
383 	return ret;
384 
385 err:
386 	/* We've started the module so we'd better finish it */
387 	if (pmod->finish && init_called)
388 		pmod->finish(imod);
389 
390 memerr:
391 	if (imod) {
392 		free(imod->name);
393 		free(imod->value);
394 		free(imod);
395 	}
396 
397 	return -1;
398 }
399 
400 /* Unload any dynamic modules that have a link count of zero:
401  * i.e. have no active initialized modules. If 'all' is set
402  * then all modules are unloaded including static ones.
403  */
404 
405 void
406 CONF_modules_unload(int all)
407 {
408 	int i;
409 	CONF_MODULE *md;
410 
411 	CONF_modules_finish();
412 
413 	/* unload modules in reverse order */
414 	for (i = sk_CONF_MODULE_num(supported_modules) - 1; i >= 0; i--) {
415 		md = sk_CONF_MODULE_value(supported_modules, i);
416 		/* If static or in use and 'all' not set ignore it */
417 		if (((md->links > 0) || !md->dso) && !all)
418 			continue;
419 		/* Since we're working in reverse this is OK */
420 		(void)sk_CONF_MODULE_delete(supported_modules, i);
421 		module_free(md);
422 	}
423 	if (sk_CONF_MODULE_num(supported_modules) == 0) {
424 		sk_CONF_MODULE_free(supported_modules);
425 		supported_modules = NULL;
426 	}
427 }
428 
429 /* unload a single module */
430 static void
431 module_free(CONF_MODULE *md)
432 {
433 	if (md->dso)
434 		DSO_free(md->dso);
435 	free(md->name);
436 	free(md);
437 }
438 
439 /* finish and free up all modules instances */
440 
441 void
442 CONF_modules_finish(void)
443 {
444 	CONF_IMODULE *imod;
445 
446 	while (sk_CONF_IMODULE_num(initialized_modules) > 0) {
447 		imod = sk_CONF_IMODULE_pop(initialized_modules);
448 		module_finish(imod);
449 	}
450 	sk_CONF_IMODULE_free(initialized_modules);
451 	initialized_modules = NULL;
452 }
453 
454 /* finish a module instance */
455 
456 static void
457 module_finish(CONF_IMODULE *imod)
458 {
459 	if (imod->pmod->finish)
460 		imod->pmod->finish(imod);
461 	imod->pmod->links--;
462 	free(imod->name);
463 	free(imod->value);
464 	free(imod);
465 }
466 
467 /* Add a static module to OpenSSL */
468 
469 int
470 CONF_module_add(const char *name, conf_init_func *ifunc,
471     conf_finish_func *ffunc)
472 {
473 	if (module_add(NULL, name, ifunc, ffunc))
474 		return 1;
475 	else
476 		return 0;
477 }
478 
479 void
480 CONF_modules_free(void)
481 {
482 	CONF_modules_finish();
483 	CONF_modules_unload(1);
484 }
485 
486 /* Utility functions */
487 
488 const char *
489 CONF_imodule_get_name(const CONF_IMODULE *md)
490 {
491 	return md->name;
492 }
493 
494 const char *
495 CONF_imodule_get_value(const CONF_IMODULE *md)
496 {
497 	return md->value;
498 }
499 
500 void *
501 CONF_imodule_get_usr_data(const CONF_IMODULE *md)
502 {
503 	return md->usr_data;
504 }
505 
506 void
507 CONF_imodule_set_usr_data(CONF_IMODULE *md, void *usr_data)
508 {
509 	md->usr_data = usr_data;
510 }
511 
512 CONF_MODULE *
513 CONF_imodule_get_module(const CONF_IMODULE *md)
514 {
515 	return md->pmod;
516 }
517 
518 unsigned long
519 CONF_imodule_get_flags(const CONF_IMODULE *md)
520 {
521 	return md->flags;
522 }
523 
524 void
525 CONF_imodule_set_flags(CONF_IMODULE *md, unsigned long flags)
526 {
527 	md->flags = flags;
528 }
529 
530 void *
531 CONF_module_get_usr_data(CONF_MODULE *pmod)
532 {
533 	return pmod->usr_data;
534 }
535 
536 void
537 CONF_module_set_usr_data(CONF_MODULE *pmod, void *usr_data)
538 {
539 	pmod->usr_data = usr_data;
540 }
541 
542 /* Return default config file name */
543 
544 char *
545 CONF_get1_default_config_file(void)
546 {
547 	char *file = NULL;
548 
549 	if (asprintf(&file, "%s/openssl.cnf",
550 	    X509_get_default_cert_area()) == -1)
551 		return (NULL);
552 	return file;
553 }
554 
555 /* This function takes a list separated by 'sep' and calls the
556  * callback function giving the start and length of each member
557  * optionally stripping leading and trailing whitespace. This can
558  * be used to parse comma separated lists for example.
559  */
560 
561 int
562 CONF_parse_list(const char *list_, int sep, int nospc,
563     int (*list_cb)(const char *elem, int len, void *usr), void *arg)
564 {
565 	int ret;
566 	const char *lstart, *tmpend, *p;
567 
568 	if (list_ == NULL) {
569 		CONFerr(CONF_F_CONF_PARSE_LIST, CONF_R_LIST_CANNOT_BE_NULL);
570 		return 0;
571 	}
572 
573 	lstart = list_;
574 	for (;;) {
575 		if (nospc) {
576 			while (*lstart && isspace((unsigned char)*lstart))
577 				lstart++;
578 		}
579 		p = strchr(lstart, sep);
580 		if (p == lstart || !*lstart)
581 			ret = list_cb(NULL, 0, arg);
582 		else {
583 			if (p)
584 				tmpend = p - 1;
585 			else
586 				tmpend = lstart + strlen(lstart) - 1;
587 			if (nospc) {
588 				while (isspace((unsigned char)*tmpend))
589 					tmpend--;
590 			}
591 			ret = list_cb(lstart, tmpend - lstart + 1, arg);
592 		}
593 		if (ret <= 0)
594 			return ret;
595 		if (p == NULL)
596 			return 1;
597 		lstart = p + 1;
598 	}
599 }
600