xref: /freebsd/crypto/openssl/crypto/conf/conf_mod.c (revision e0c4386e)
1 /*
2  * Copyright 2002-2023 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (the "License").  You may not use
5  * this file except in compliance with the License.  You can obtain a copy
6  * in the file LICENSE in the source distribution or at
7  * https://www.openssl.org/source/license.html
8  */
9 
10 /* We need to use some engine deprecated APIs */
11 #define OPENSSL_SUPPRESS_DEPRECATED
12 
13 #include "internal/cryptlib.h"
14 #include <stdio.h>
15 #include <ctype.h>
16 #include <openssl/crypto.h>
17 #include "internal/conf.h"
18 #include <openssl/conf_api.h>
19 #include "internal/dso.h"
20 #include "internal/thread_once.h"
21 #include <openssl/x509.h>
22 #include <openssl/trace.h>
23 #include <openssl/engine.h>
24 #include "conf_local.h"
25 
26 DEFINE_STACK_OF(CONF_MODULE)
27 DEFINE_STACK_OF(CONF_IMODULE)
28 
29 #define DSO_mod_init_name "OPENSSL_init"
30 #define DSO_mod_finish_name "OPENSSL_finish"
31 
32 /*
33  * This structure contains a data about supported modules. entries in this
34  * table correspond to either dynamic or static modules.
35  */
36 
37 struct conf_module_st {
38     /* DSO of this module or NULL if static */
39     DSO *dso;
40     /* Name of the module */
41     char *name;
42     /* Init function */
43     conf_init_func *init;
44     /* Finish function */
45     conf_finish_func *finish;
46     /* Number of successfully initialized modules */
47     int links;
48     void *usr_data;
49 };
50 
51 /*
52  * This structure contains information about modules that have been
53  * successfully initialized. There may be more than one entry for a given
54  * module.
55  */
56 
57 struct conf_imodule_st {
58     CONF_MODULE *pmod;
59     char *name;
60     char *value;
61     unsigned long flags;
62     void *usr_data;
63 };
64 
65 static CRYPTO_ONCE init_module_list_lock = CRYPTO_ONCE_STATIC_INIT;
66 static CRYPTO_RWLOCK *module_list_lock = NULL;
67 static STACK_OF(CONF_MODULE) *supported_modules = NULL; /* protected by lock */
68 static STACK_OF(CONF_IMODULE) *initialized_modules = NULL; /* protected by lock */
69 
70 static CRYPTO_ONCE load_builtin_modules = CRYPTO_ONCE_STATIC_INIT;
71 
72 static void module_free(CONF_MODULE *md);
73 static void module_finish(CONF_IMODULE *imod);
74 static int module_run(const CONF *cnf, const char *name, const char *value,
75                       unsigned long flags);
76 static CONF_MODULE *module_add(DSO *dso, const char *name,
77                                conf_init_func *ifunc,
78                                conf_finish_func *ffunc);
79 static CONF_MODULE *module_find(const char *name);
80 static int module_init(CONF_MODULE *pmod, const char *name, const char *value,
81                        const CONF *cnf);
82 static CONF_MODULE *module_load_dso(const CONF *cnf, const char *name,
83                                     const char *value);
84 
85 static int conf_modules_finish_int(void);
86 
87 static void module_lists_free(void)
88 {
89     CRYPTO_THREAD_lock_free(module_list_lock);
90     module_list_lock = NULL;
91 
92     sk_CONF_MODULE_free(supported_modules);
93     supported_modules = NULL;
94 
95     sk_CONF_IMODULE_free(initialized_modules);
96     initialized_modules = NULL;
97 }
98 
99 DEFINE_RUN_ONCE_STATIC(do_init_module_list_lock)
100 {
101     module_list_lock = CRYPTO_THREAD_lock_new();
102     if (module_list_lock == NULL) {
103         ERR_raise(ERR_LIB_CONF, ERR_R_MALLOC_FAILURE);
104         return 0;
105     }
106 
107     return 1;
108 }
109 
110 static int conf_diagnostics(const CONF *cnf)
111 {
112     return _CONF_get_number(cnf, NULL, "config_diagnostics") != 0;
113 }
114 
115 /* Main function: load modules from a CONF structure */
116 
117 int CONF_modules_load(const CONF *cnf, const char *appname,
118                       unsigned long flags)
119 {
120     STACK_OF(CONF_VALUE) *values;
121     CONF_VALUE *vl;
122     char *vsection = NULL;
123     int ret, i;
124 
125     if (!cnf)
126         return 1;
127 
128     if (conf_diagnostics(cnf))
129         flags &= ~(CONF_MFLAGS_IGNORE_ERRORS
130                    | CONF_MFLAGS_IGNORE_RETURN_CODES
131                    | CONF_MFLAGS_SILENT
132                    | CONF_MFLAGS_IGNORE_MISSING_FILE);
133 
134     ERR_set_mark();
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_pop_to_mark();
143         return 1;
144     }
145 
146     OSSL_TRACE1(CONF, "Configuration in section %s\n", vsection);
147     values = NCONF_get_section(cnf, vsection);
148 
149     if (values == NULL) {
150         if (!(flags & CONF_MFLAGS_SILENT)) {
151             ERR_clear_last_mark();
152             ERR_raise_data(ERR_LIB_CONF,
153                            CONF_R_OPENSSL_CONF_REFERENCES_MISSING_SECTION,
154                            "openssl_conf=%s", vsection);
155         } else {
156             ERR_pop_to_mark();
157         }
158         return 0;
159     }
160     ERR_pop_to_mark();
161 
162     for (i = 0; i < sk_CONF_VALUE_num(values); i++) {
163         vl = sk_CONF_VALUE_value(values, i);
164         ERR_set_mark();
165         ret = module_run(cnf, vl->name, vl->value, flags);
166         OSSL_TRACE3(CONF, "Running module %s (%s) returned %d\n",
167                     vl->name, vl->value, ret);
168         if (ret <= 0)
169             if (!(flags & CONF_MFLAGS_IGNORE_ERRORS)) {
170                 ERR_clear_last_mark();
171                 return ret;
172             }
173         ERR_pop_to_mark();
174     }
175 
176     return 1;
177 
178 }
179 
180 int CONF_modules_load_file_ex(OSSL_LIB_CTX *libctx, const char *filename,
181                               const char *appname, unsigned long flags)
182 {
183     char *file = NULL;
184     CONF *conf = NULL;
185     int ret = 0, diagnostics = 0;
186 
187     ERR_set_mark();
188 
189     if (filename == NULL) {
190         file = CONF_get1_default_config_file();
191         if (file == NULL)
192             goto err;
193         if (*file == '\0') {
194             /* Do not try to load an empty file name but do not error out */
195             ret = 1;
196             goto err;
197         }
198     } else {
199         file = (char *)filename;
200     }
201 
202     conf = NCONF_new_ex(libctx, NULL);
203     if (conf == NULL)
204         goto err;
205 
206     if (NCONF_load(conf, file, NULL) <= 0) {
207         if ((flags & CONF_MFLAGS_IGNORE_MISSING_FILE) &&
208             (ERR_GET_REASON(ERR_peek_last_error()) == CONF_R_NO_SUCH_FILE)) {
209             ret = 1;
210         }
211         goto err;
212     }
213 
214     ret = CONF_modules_load(conf, appname, flags);
215     diagnostics = conf_diagnostics(conf);
216 
217  err:
218     if (filename == NULL)
219         OPENSSL_free(file);
220     NCONF_free(conf);
221 
222     if ((flags & CONF_MFLAGS_IGNORE_RETURN_CODES) != 0 && !diagnostics)
223         ret = 1;
224 
225     if (ret > 0)
226         ERR_pop_to_mark();
227     else
228         ERR_clear_last_mark();
229 
230     return ret;
231 }
232 
233 int CONF_modules_load_file(const char *filename,
234                            const char *appname, unsigned long flags)
235 {
236     return CONF_modules_load_file_ex(NULL, filename, appname, flags);
237 }
238 
239 DEFINE_RUN_ONCE_STATIC(do_load_builtin_modules)
240 {
241     OPENSSL_load_builtin_modules();
242 #ifndef OPENSSL_NO_ENGINE
243     /* Need to load ENGINEs */
244     ENGINE_load_builtin_engines();
245 #endif
246     return 1;
247 }
248 
249 static int module_run(const CONF *cnf, const char *name, const char *value,
250                       unsigned long flags)
251 {
252     CONF_MODULE *md;
253     int ret;
254 
255     if (!RUN_ONCE(&load_builtin_modules, do_load_builtin_modules))
256         return -1;
257 
258     md = module_find(name);
259 
260     /* Module not found: try to load DSO */
261     if (!md && !(flags & CONF_MFLAGS_NO_DSO))
262         md = module_load_dso(cnf, name, value);
263 
264     if (!md) {
265         if (!(flags & CONF_MFLAGS_SILENT)) {
266             ERR_raise_data(ERR_LIB_CONF, CONF_R_UNKNOWN_MODULE_NAME,
267                            "module=%s", name);
268         }
269         return -1;
270     }
271 
272     ret = module_init(md, name, value, cnf);
273 
274     if (ret <= 0) {
275         if (!(flags & CONF_MFLAGS_SILENT))
276             ERR_raise_data(ERR_LIB_CONF, CONF_R_MODULE_INITIALIZATION_ERROR,
277                            "module=%s, value=%s retcode=%-8d",
278                            name, value, ret);
279     }
280 
281     return ret;
282 }
283 
284 /* Load a module from a DSO */
285 static CONF_MODULE *module_load_dso(const CONF *cnf,
286                                     const char *name, const char *value)
287 {
288     DSO *dso = NULL;
289     conf_init_func *ifunc;
290     conf_finish_func *ffunc;
291     const char *path = NULL;
292     int errcode = 0;
293     CONF_MODULE *md;
294 
295     /* Look for alternative path in module section */
296     path = _CONF_get_string(cnf, value, "path");
297     if (path == NULL) {
298         path = name;
299     }
300     dso = DSO_load(NULL, path, NULL, 0);
301     if (dso == NULL) {
302         errcode = CONF_R_ERROR_LOADING_DSO;
303         goto err;
304     }
305     ifunc = (conf_init_func *)DSO_bind_func(dso, DSO_mod_init_name);
306     if (ifunc == NULL) {
307         errcode = CONF_R_MISSING_INIT_FUNCTION;
308         goto err;
309     }
310     ffunc = (conf_finish_func *)DSO_bind_func(dso, DSO_mod_finish_name);
311     /* All OK, add module */
312     md = module_add(dso, name, ifunc, ffunc);
313 
314     if (md == NULL)
315         goto err;
316 
317     return md;
318 
319  err:
320     DSO_free(dso);
321     ERR_raise_data(ERR_LIB_CONF, errcode, "module=%s, path=%s", name, path);
322     return NULL;
323 }
324 
325 /* add module to list */
326 static CONF_MODULE *module_add(DSO *dso, const char *name,
327                                conf_init_func *ifunc, conf_finish_func *ffunc)
328 {
329     CONF_MODULE *tmod = NULL;
330 
331     if (!RUN_ONCE(&init_module_list_lock, do_init_module_list_lock))
332         return NULL;
333 
334     if (!CRYPTO_THREAD_write_lock(module_list_lock))
335         return NULL;
336 
337     if (supported_modules == NULL)
338         supported_modules = sk_CONF_MODULE_new_null();
339     if (supported_modules == NULL)
340         goto err;
341     if ((tmod = OPENSSL_zalloc(sizeof(*tmod))) == NULL) {
342         ERR_raise(ERR_LIB_CONF, ERR_R_MALLOC_FAILURE);
343         goto err;
344     }
345 
346     tmod->dso = dso;
347     tmod->name = OPENSSL_strdup(name);
348     tmod->init = ifunc;
349     tmod->finish = ffunc;
350     if (tmod->name == NULL)
351         goto err;
352 
353     if (!sk_CONF_MODULE_push(supported_modules, tmod))
354         goto err;
355 
356     CRYPTO_THREAD_unlock(module_list_lock);
357     return tmod;
358 
359  err:
360     CRYPTO_THREAD_unlock(module_list_lock);
361     if (tmod != NULL) {
362         OPENSSL_free(tmod->name);
363         OPENSSL_free(tmod);
364     }
365     return NULL;
366 }
367 
368 /*
369  * Find a module from the list. We allow module names of the form
370  * modname.XXXX to just search for modname to allow the same module to be
371  * initialized more than once.
372  */
373 
374 static CONF_MODULE *module_find(const char *name)
375 {
376     CONF_MODULE *tmod;
377     int i, nchar;
378     char *p;
379     p = strrchr(name, '.');
380 
381     if (p)
382         nchar = p - name;
383     else
384         nchar = strlen(name);
385 
386     if (!RUN_ONCE(&init_module_list_lock, do_init_module_list_lock))
387         return NULL;
388 
389     if (!CRYPTO_THREAD_read_lock(module_list_lock))
390         return NULL;
391 
392     for (i = 0; i < sk_CONF_MODULE_num(supported_modules); i++) {
393         tmod = sk_CONF_MODULE_value(supported_modules, i);
394         if (strncmp(tmod->name, name, nchar) == 0) {
395             CRYPTO_THREAD_unlock(module_list_lock);
396             return tmod;
397         }
398     }
399 
400     CRYPTO_THREAD_unlock(module_list_lock);
401     return NULL;
402 }
403 
404 /* initialize a module */
405 static int module_init(CONF_MODULE *pmod, const char *name, const char *value,
406                        const CONF *cnf)
407 {
408     int ret = 1;
409     int init_called = 0;
410     CONF_IMODULE *imod = NULL;
411 
412     /* Otherwise add initialized module to list */
413     imod = OPENSSL_malloc(sizeof(*imod));
414     if (imod == NULL)
415         goto err;
416 
417     imod->pmod = pmod;
418     imod->name = OPENSSL_strdup(name);
419     imod->value = OPENSSL_strdup(value);
420     imod->usr_data = NULL;
421 
422     if (!imod->name || !imod->value)
423         goto memerr;
424 
425     /* Try to initialize module */
426     if (pmod->init) {
427         ret = pmod->init(imod, cnf);
428         init_called = 1;
429         /* Error occurred, exit */
430         if (ret <= 0)
431             goto err;
432     }
433 
434     if (!RUN_ONCE(&init_module_list_lock, do_init_module_list_lock))
435         goto err;
436 
437     if (!CRYPTO_THREAD_write_lock(module_list_lock))
438         goto err;
439 
440     if (initialized_modules == NULL) {
441         initialized_modules = sk_CONF_IMODULE_new_null();
442         if (initialized_modules == NULL) {
443             CRYPTO_THREAD_unlock(module_list_lock);
444             ERR_raise(ERR_LIB_CONF, ERR_R_MALLOC_FAILURE);
445             goto err;
446         }
447     }
448 
449     if (!sk_CONF_IMODULE_push(initialized_modules, imod)) {
450         CRYPTO_THREAD_unlock(module_list_lock);
451         ERR_raise(ERR_LIB_CONF, ERR_R_MALLOC_FAILURE);
452         goto err;
453     }
454 
455     pmod->links++;
456 
457     CRYPTO_THREAD_unlock(module_list_lock);
458     return ret;
459 
460  err:
461 
462     /* We've started the module so we'd better finish it */
463     if (pmod->finish && init_called)
464         pmod->finish(imod);
465 
466  memerr:
467     if (imod) {
468         OPENSSL_free(imod->name);
469         OPENSSL_free(imod->value);
470         OPENSSL_free(imod);
471     }
472 
473     return -1;
474 
475 }
476 
477 /*
478  * Unload any dynamic modules that have a link count of zero: i.e. have no
479  * active initialized modules. If 'all' is set then all modules are unloaded
480  * including static ones.
481  */
482 
483 void CONF_modules_unload(int all)
484 {
485     int i;
486     CONF_MODULE *md;
487 
488     if (!conf_modules_finish_int()) /* also inits module list lock */
489         return;
490 
491     if (!CRYPTO_THREAD_write_lock(module_list_lock))
492         return;
493 
494     /* unload modules in reverse order */
495     for (i = sk_CONF_MODULE_num(supported_modules) - 1; i >= 0; i--) {
496         md = sk_CONF_MODULE_value(supported_modules, i);
497         /* If static or in use and 'all' not set ignore it */
498         if (((md->links > 0) || !md->dso) && !all)
499             continue;
500         /* Since we're working in reverse this is OK */
501         (void)sk_CONF_MODULE_delete(supported_modules, i);
502         module_free(md);
503     }
504 
505     if (sk_CONF_MODULE_num(supported_modules) == 0) {
506         sk_CONF_MODULE_free(supported_modules);
507         supported_modules = NULL;
508     }
509 
510     CRYPTO_THREAD_unlock(module_list_lock);
511 }
512 
513 /* unload a single module */
514 static void module_free(CONF_MODULE *md)
515 {
516     DSO_free(md->dso);
517     OPENSSL_free(md->name);
518     OPENSSL_free(md);
519 }
520 
521 /* finish and free up all modules instances */
522 
523 static int conf_modules_finish_int(void)
524 {
525     CONF_IMODULE *imod;
526 
527     if (!RUN_ONCE(&init_module_list_lock, do_init_module_list_lock))
528         return 0;
529 
530     /* If module_list_lock is NULL here it means we were already unloaded */
531     if (module_list_lock == NULL
532         || !CRYPTO_THREAD_write_lock(module_list_lock))
533         return 0;
534 
535     while (sk_CONF_IMODULE_num(initialized_modules) > 0) {
536         imod = sk_CONF_IMODULE_pop(initialized_modules);
537         module_finish(imod);
538     }
539     sk_CONF_IMODULE_free(initialized_modules);
540     initialized_modules = NULL;
541 
542     CRYPTO_THREAD_unlock(module_list_lock);
543 
544     return 1;
545 }
546 
547 void CONF_modules_finish(void)
548 {
549     conf_modules_finish_int();
550 }
551 
552 /* finish a module instance */
553 
554 static void module_finish(CONF_IMODULE *imod)
555 {
556     if (!imod)
557         return;
558     if (imod->pmod->finish)
559         imod->pmod->finish(imod);
560     imod->pmod->links--;
561     OPENSSL_free(imod->name);
562     OPENSSL_free(imod->value);
563     OPENSSL_free(imod);
564 }
565 
566 /* Add a static module to OpenSSL */
567 
568 int CONF_module_add(const char *name, conf_init_func *ifunc,
569                     conf_finish_func *ffunc)
570 {
571     if (module_add(NULL, name, ifunc, ffunc))
572         return 1;
573     else
574         return 0;
575 }
576 
577 void ossl_config_modules_free(void)
578 {
579     CONF_modules_unload(1); /* calls CONF_modules_finish */
580     module_lists_free();
581 }
582 
583 /* Utility functions */
584 
585 const char *CONF_imodule_get_name(const CONF_IMODULE *md)
586 {
587     return md->name;
588 }
589 
590 const char *CONF_imodule_get_value(const CONF_IMODULE *md)
591 {
592     return md->value;
593 }
594 
595 void *CONF_imodule_get_usr_data(const CONF_IMODULE *md)
596 {
597     return md->usr_data;
598 }
599 
600 void CONF_imodule_set_usr_data(CONF_IMODULE *md, void *usr_data)
601 {
602     md->usr_data = usr_data;
603 }
604 
605 CONF_MODULE *CONF_imodule_get_module(const CONF_IMODULE *md)
606 {
607     return md->pmod;
608 }
609 
610 unsigned long CONF_imodule_get_flags(const CONF_IMODULE *md)
611 {
612     return md->flags;
613 }
614 
615 void CONF_imodule_set_flags(CONF_IMODULE *md, unsigned long flags)
616 {
617     md->flags = flags;
618 }
619 
620 void *CONF_module_get_usr_data(CONF_MODULE *pmod)
621 {
622     return pmod->usr_data;
623 }
624 
625 void CONF_module_set_usr_data(CONF_MODULE *pmod, void *usr_data)
626 {
627     pmod->usr_data = usr_data;
628 }
629 
630 /* Return default config file name */
631 char *CONF_get1_default_config_file(void)
632 {
633     const char *t;
634     char *file, *sep = "";
635     size_t size;
636 
637     if ((file = ossl_safe_getenv("OPENSSL_CONF")) != NULL)
638         return OPENSSL_strdup(file);
639 
640     t = X509_get_default_cert_area();
641 #ifndef OPENSSL_SYS_VMS
642     sep = "/";
643 #endif
644     size = strlen(t) + strlen(sep) + strlen(OPENSSL_CONF) + 1;
645     file = OPENSSL_malloc(size);
646 
647     if (file == NULL)
648         return NULL;
649     BIO_snprintf(file, size, "%s%s%s", t, sep, OPENSSL_CONF);
650 
651     return file;
652 }
653 
654 /*
655  * This function takes a list separated by 'sep' and calls the callback
656  * function giving the start and length of each member optionally stripping
657  * leading and trailing whitespace. This can be used to parse comma separated
658  * lists for example.
659  */
660 
661 int CONF_parse_list(const char *list_, int sep, int nospc,
662                     int (*list_cb) (const char *elem, int len, void *usr),
663                     void *arg)
664 {
665     int ret;
666     const char *lstart, *tmpend, *p;
667 
668     if (list_ == NULL) {
669         ERR_raise(ERR_LIB_CONF, CONF_R_LIST_CANNOT_BE_NULL);
670         return 0;
671     }
672 
673     lstart = list_;
674     for (;;) {
675         if (nospc) {
676             while (*lstart && isspace((unsigned char)*lstart))
677                 lstart++;
678         }
679         p = strchr(lstart, sep);
680         if (p == lstart || *lstart == '\0')
681             ret = list_cb(NULL, 0, arg);
682         else {
683             if (p)
684                 tmpend = p - 1;
685             else
686                 tmpend = lstart + strlen(lstart) - 1;
687             if (nospc) {
688                 while (isspace((unsigned char)*tmpend))
689                     tmpend--;
690             }
691             ret = list_cb(lstart, tmpend - lstart + 1, arg);
692         }
693         if (ret <= 0)
694             return ret;
695         if (p == NULL)
696             return 1;
697         lstart = p + 1;
698     }
699 }
700