xref: /openbsd/lib/libcrypto/conf/conf_mod.c (revision 3cab2bb3) 
1 /* $OpenBSD: conf_mod.c,v 1.27 2017/01/29 17:49:22 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 			CONFerror(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 			CONFerror(CONF_R_MODULE_INITIALIZATION_ERROR);
225 			ERR_asprintf_error_data
226 			    ("module=%s, value=%s, retcode=%-8d",
227 			    name, value, ret);
228 		}
229 	}
230 
231 	return ret;
232 }
233 
234 /* Load a module from a DSO */
235 static CONF_MODULE *
236 module_load_dso(const CONF *cnf, char *name, char *value, unsigned long flags)
237 {
238 	DSO *dso = NULL;
239 	conf_init_func *ifunc;
240 	conf_finish_func *ffunc;
241 	char *path = NULL;
242 	int errcode = 0;
243 	CONF_MODULE *md;
244 
245 	/* Look for alternative path in module section */
246 	path = NCONF_get_string(cnf, value, "path");
247 	if (!path) {
248 		ERR_clear_error();
249 		path = name;
250 	}
251 	dso = DSO_load(NULL, path, NULL, 0);
252 	if (!dso) {
253 		errcode = CONF_R_ERROR_LOADING_DSO;
254 		goto err;
255 	}
256 	ifunc = (conf_init_func *)DSO_bind_func(dso, DSO_mod_init_name);
257 	if (!ifunc) {
258 		errcode = CONF_R_MISSING_INIT_FUNCTION;
259 		goto err;
260 	}
261 	ffunc = (conf_finish_func *)DSO_bind_func(dso, DSO_mod_finish_name);
262 	/* All OK, add module */
263 	md = module_add(dso, name, ifunc, ffunc);
264 
265 	if (!md)
266 		goto err;
267 
268 	return md;
269 
270 err:
271 	if (dso)
272 		DSO_free(dso);
273 	CONFerror(errcode);
274 	ERR_asprintf_error_data("module=%s, path=%s", name, path);
275 	return NULL;
276 }
277 
278 /* add module to list */
279 static CONF_MODULE *
280 module_add(DSO *dso, const char *name, conf_init_func *ifunc,
281     conf_finish_func *ffunc)
282 {
283 	CONF_MODULE *tmod = NULL;
284 
285 	if (name == NULL)
286 		return NULL;
287 	if (supported_modules == NULL)
288 		supported_modules = sk_CONF_MODULE_new_null();
289 	if (supported_modules == NULL)
290 		return NULL;
291 	tmod = malloc(sizeof(CONF_MODULE));
292 	if (tmod == NULL)
293 		return NULL;
294 
295 	tmod->dso = dso;
296 	tmod->name = strdup(name);
297 	tmod->init = ifunc;
298 	tmod->finish = ffunc;
299 	tmod->links = 0;
300 
301 	if (!sk_CONF_MODULE_push(supported_modules, tmod)) {
302 		free(tmod);
303 		return NULL;
304 	}
305 
306 	return tmod;
307 }
308 
309 /* Find a module from the list. We allow module names of the
310  * form modname.XXXX to just search for modname to allow the
311  * same module to be initialized more than once.
312  */
313 
314 static CONF_MODULE *
315 module_find(char *name)
316 {
317 	CONF_MODULE *tmod;
318 	int i, nchar;
319 	char *p;
320 
321 	p = strrchr(name, '.');
322 
323 	if (p)
324 		nchar = p - name;
325 	else
326 		nchar = strlen(name);
327 
328 	for (i = 0; i < sk_CONF_MODULE_num(supported_modules); i++) {
329 		tmod = sk_CONF_MODULE_value(supported_modules, i);
330 		if (!strncmp(tmod->name, name, nchar))
331 			return tmod;
332 	}
333 
334 	return NULL;
335 }
336 
337 /* initialize a module */
338 static int
339 module_init(CONF_MODULE *pmod, char *name, char *value, const CONF *cnf)
340 {
341 	int ret = 1;
342 	int init_called = 0;
343 	CONF_IMODULE *imod = NULL;
344 
345 	/* Otherwise add initialized module to list */
346 	imod = malloc(sizeof(CONF_IMODULE));
347 	if (!imod)
348 		goto err;
349 
350 	imod->pmod = pmod;
351 	imod->name = name ? strdup(name) : NULL;
352 	imod->value = value ? strdup(value) : NULL;
353 	imod->usr_data = NULL;
354 
355 	if (!imod->name || !imod->value)
356 		goto memerr;
357 
358 	/* Try to initialize module */
359 	if (pmod->init) {
360 		ret = pmod->init(imod, cnf);
361 		init_called = 1;
362 		/* Error occurred, exit */
363 		if (ret <= 0)
364 			goto err;
365 	}
366 
367 	if (initialized_modules == NULL) {
368 		initialized_modules = sk_CONF_IMODULE_new_null();
369 		if (!initialized_modules) {
370 			CONFerror(ERR_R_MALLOC_FAILURE);
371 			goto err;
372 		}
373 	}
374 
375 	if (!sk_CONF_IMODULE_push(initialized_modules, imod)) {
376 		CONFerror(ERR_R_MALLOC_FAILURE);
377 		goto err;
378 	}
379 
380 	pmod->links++;
381 
382 	return ret;
383 
384 err:
385 	/* We've started the module so we'd better finish it */
386 	if (pmod->finish && init_called)
387 		pmod->finish(imod);
388 
389 memerr:
390 	if (imod) {
391 		free(imod->name);
392 		free(imod->value);
393 		free(imod);
394 	}
395 
396 	return -1;
397 }
398 
399 /* Unload any dynamic modules that have a link count of zero:
400  * i.e. have no active initialized modules. If 'all' is set
401  * then all modules are unloaded including static ones.
402  */
403 
404 void
405 CONF_modules_unload(int all)
406 {
407 	int i;
408 	CONF_MODULE *md;
409 
410 	CONF_modules_finish();
411 
412 	/* unload modules in reverse order */
413 	for (i = sk_CONF_MODULE_num(supported_modules) - 1; i >= 0; i--) {
414 		md = sk_CONF_MODULE_value(supported_modules, i);
415 		/* If static or in use and 'all' not set ignore it */
416 		if (((md->links > 0) || !md->dso) && !all)
417 			continue;
418 		/* Since we're working in reverse this is OK */
419 		(void)sk_CONF_MODULE_delete(supported_modules, i);
420 		module_free(md);
421 	}
422 	if (sk_CONF_MODULE_num(supported_modules) == 0) {
423 		sk_CONF_MODULE_free(supported_modules);
424 		supported_modules = NULL;
425 	}
426 }
427 
428 /* unload a single module */
429 static void
430 module_free(CONF_MODULE *md)
431 {
432 	if (md->dso)
433 		DSO_free(md->dso);
434 	free(md->name);
435 	free(md);
436 }
437 
438 /* finish and free up all modules instances */
439 
440 void
441 CONF_modules_finish(void)
442 {
443 	CONF_IMODULE *imod;
444 
445 	while (sk_CONF_IMODULE_num(initialized_modules) > 0) {
446 		imod = sk_CONF_IMODULE_pop(initialized_modules);
447 		module_finish(imod);
448 	}
449 	sk_CONF_IMODULE_free(initialized_modules);
450 	initialized_modules = NULL;
451 }
452 
453 /* finish a module instance */
454 
455 static void
456 module_finish(CONF_IMODULE *imod)
457 {
458 	if (imod->pmod->finish)
459 		imod->pmod->finish(imod);
460 	imod->pmod->links--;
461 	free(imod->name);
462 	free(imod->value);
463 	free(imod);
464 }
465 
466 /* Add a static module to OpenSSL */
467 
468 int
469 CONF_module_add(const char *name, conf_init_func *ifunc,
470     conf_finish_func *ffunc)
471 {
472 	if (module_add(NULL, name, ifunc, ffunc))
473 		return 1;
474 	else
475 		return 0;
476 }
477 
478 void
479 CONF_modules_free(void)
480 {
481 	CONF_modules_finish();
482 	CONF_modules_unload(1);
483 }
484 
485 /* Utility functions */
486 
487 const char *
488 CONF_imodule_get_name(const CONF_IMODULE *md)
489 {
490 	return md->name;
491 }
492 
493 const char *
494 CONF_imodule_get_value(const CONF_IMODULE *md)
495 {
496 	return md->value;
497 }
498 
499 void *
500 CONF_imodule_get_usr_data(const CONF_IMODULE *md)
501 {
502 	return md->usr_data;
503 }
504 
505 void
506 CONF_imodule_set_usr_data(CONF_IMODULE *md, void *usr_data)
507 {
508 	md->usr_data = usr_data;
509 }
510 
511 CONF_MODULE *
512 CONF_imodule_get_module(const CONF_IMODULE *md)
513 {
514 	return md->pmod;
515 }
516 
517 unsigned long
518 CONF_imodule_get_flags(const CONF_IMODULE *md)
519 {
520 	return md->flags;
521 }
522 
523 void
524 CONF_imodule_set_flags(CONF_IMODULE *md, unsigned long flags)
525 {
526 	md->flags = flags;
527 }
528 
529 void *
530 CONF_module_get_usr_data(CONF_MODULE *pmod)
531 {
532 	return pmod->usr_data;
533 }
534 
535 void
536 CONF_module_set_usr_data(CONF_MODULE *pmod, void *usr_data)
537 {
538 	pmod->usr_data = usr_data;
539 }
540 
541 /* Return default config file name */
542 
543 char *
544 CONF_get1_default_config_file(void)
545 {
546 	char *file = NULL;
547 
548 	if (asprintf(&file, "%s/openssl.cnf",
549 	    X509_get_default_cert_area()) == -1)
550 		return (NULL);
551 	return file;
552 }
553 
554 /* This function takes a list separated by 'sep' and calls the
555  * callback function giving the start and length of each member
556  * optionally stripping leading and trailing whitespace. This can
557  * be used to parse comma separated lists for example.
558  */
559 
560 int
561 CONF_parse_list(const char *list_, int sep, int nospc,
562     int (*list_cb)(const char *elem, int len, void *usr), void *arg)
563 {
564 	int ret;
565 	const char *lstart, *tmpend, *p;
566 
567 	if (list_ == NULL) {
568 		CONFerror(CONF_R_LIST_CANNOT_BE_NULL);
569 		return 0;
570 	}
571 
572 	lstart = list_;
573 	for (;;) {
574 		if (nospc) {
575 			while (*lstart && isspace((unsigned char)*lstart))
576 				lstart++;
577 		}
578 		p = strchr(lstart, sep);
579 		if (p == lstart || !*lstart)
580 			ret = list_cb(NULL, 0, arg);
581 		else {
582 			if (p)
583 				tmpend = p - 1;
584 			else
585 				tmpend = lstart + strlen(lstart) - 1;
586 			if (nospc) {
587 				while (isspace((unsigned char)*tmpend))
588 					tmpend--;
589 			}
590 			ret = list_cb(lstart, tmpend - lstart + 1, arg);
591 		}
592 		if (ret <= 0)
593 			return ret;
594 		if (p == NULL)
595 			return 1;
596 		lstart = p + 1;
597 	}
598 }
599