crypto/conf/conf_mod.c

   1 /*
   2  * Copyright 2002-2020 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 #include "internal/cryptlib.h"
  11 #include <stdio.h>
  12 #include <ctype.h>
  13 #include <openssl/crypto.h>
  14 #include "internal/conf.h"
  15 #include "internal/dso.h"
  16 #include "internal/thread_once.h"
  17 #include <openssl/x509.h>
  18 #include <openssl/trace.h>
  19 #include <openssl/engine.h>
  20
  21 DEFINE_STACK_OF(CONF_VALUE)
  22 DEFINE_STACK_OF(CONF_MODULE)
  23 DEFINE_STACK_OF(CONF_IMODULE)
  24
  25 #define DSO_mod_init_name "OPENSSL_init"
  26 #define DSO_mod_finish_name "OPENSSL_finish"
  27
  28 /*
  29  * This structure contains a data about supported modules. entries in this
  30  * table correspond to either dynamic or static modules.
  31  */
  32
  33 struct conf_module_st {
  34     /* DSO of this module or NULL if static */
  35     DSO *dso;
  36     /* Name of the module */
  37     char *name;
  38     /* Init function */
  39     conf_init_func *init;
  40     /* Finish function */
  41     conf_finish_func *finish;
  42     /* Number of successfully initialized modules */
  43     int links;
  44     void *usr_data;
  45 };
  46
  47 /*
  48  * This structure contains information about modules that have been
  49  * successfully initialized. There may be more than one entry for a given
  50  * module.
  51  */
  52
  53 struct conf_imodule_st {
  54     CONF_MODULE *pmod;
  55     char *name;
  56     char *value;
  57     unsigned long flags;
  58     void *usr_data;
  59 };
  60
  61 static STACK_OF(CONF_MODULE) *supported_modules = NULL;
  62 static STACK_OF(CONF_IMODULE) *initialized_modules = NULL;
  63
  64 static CRYPTO_ONCE load_builtin_modules = CRYPTO_ONCE_STATIC_INIT;
  65
  66 static void module_free(CONF_MODULE *md);
  67 static void module_finish(CONF_IMODULE *imod);
  68 static int module_run(const CONF *cnf, const char *name, const char *value,
  69                       unsigned long flags);
  70 static CONF_MODULE *module_add(DSO *dso, const char *name,
  71                                conf_init_func *ifunc,
  72                                conf_finish_func *ffunc);
  73 static CONF_MODULE *module_find(const char *name);
  74 static int module_init(CONF_MODULE *pmod, const char *name, const char *value,
  75                        const CONF *cnf);
  76 static CONF_MODULE *module_load_dso(const CONF *cnf, const char *name,
  77                                     const char *value);
  78
  79 /* Main function: load modules from a CONF structure */
  80
  81 int CONF_modules_load(const CONF *cnf, const char *appname,
  82                       unsigned long flags)
  83 {
  84     STACK_OF(CONF_VALUE) *values;
  85     CONF_VALUE *vl;
  86     char *vsection = NULL;
  87
  88     int ret, i;
  89
  90     if (!cnf)
  91         return 1;
  92
  93     if (appname)
  94         vsection = NCONF_get_string(cnf, NULL, appname);
  95
  96     if (!appname || (!vsection && (flags & CONF_MFLAGS_DEFAULT_SECTION)))
  97         vsection = NCONF_get_string(cnf, NULL, "openssl_conf");
  98
  99     if (!vsection) {
 100         ERR_clear_error();
 101         return 1;
 102     }
 103
 104     OSSL_TRACE1(CONF, "Configuration in section %s\n", vsection);
 105     values = NCONF_get_section(cnf, vsection);
 106
 107     if (!values)
 108         return 0;
 109
 110     for (i = 0; i < sk_CONF_VALUE_num(values); i++) {
 111         vl = sk_CONF_VALUE_value(values, i);
 112         ret = module_run(cnf, vl->name, vl->value, flags);
 113         OSSL_TRACE3(CONF, "Running module %s (%s) returned %d\n",
 114                     vl->name, vl->value, ret);
 115         if (ret <= 0)
 116             if (!(flags & CONF_MFLAGS_IGNORE_ERRORS))
 117                 return ret;
 118     }
 119
 120     return 1;
 121
 122 }
 123
 124 int CONF_modules_load_file_with_libctx(OPENSSL_CTX *libctx,
 125                                        const char *filename,
 126                                        const char *appname, unsigned long flags)
 127 {
 128     char *file = NULL;
 129     CONF *conf = NULL;
 130     int ret = 0;
 131
 132     conf = NCONF_new_with_libctx(libctx, NULL);
 133     if (conf == NULL)
 134         goto err;
 135
 136     if (filename == NULL) {
 137         file = CONF_get1_default_config_file();
 138         if (file == NULL)
 139             goto err;
 140     } else {
 141         file = (char *)filename;
 142     }
 143
 144     if (NCONF_load(conf, file, NULL) <= 0) {
 145         if ((flags & CONF_MFLAGS_IGNORE_MISSING_FILE) &&
 146             (ERR_GET_REASON(ERR_peek_last_error()) == CONF_R_NO_SUCH_FILE)) {
 147             ERR_clear_error();
 148             ret = 1;
 149         }
 150         goto err;
 151     }
 152
 153     ret = CONF_modules_load(conf, appname, flags);
 154
 155  err:
 156     if (filename == NULL)
 157         OPENSSL_free(file);
 158     NCONF_free(conf);
 159
 160     if (flags & CONF_MFLAGS_IGNORE_RETURN_CODES)
 161         return 1;
 162
 163     return ret;
 164 }
 165
 166 int CONF_modules_load_file(const char *filename,
 167                            const char *appname, unsigned long flags)
 168 {
 169     return CONF_modules_load_file_with_libctx(NULL, filename, appname, flags);
 170 }
 171
 172 DEFINE_RUN_ONCE_STATIC(do_load_builtin_modules)
 173 {
 174     OPENSSL_load_builtin_modules();
 175 #ifndef OPENSSL_NO_ENGINE
 176     /* Need to load ENGINEs */
 177     ENGINE_load_builtin_engines();
 178 #endif
 179     ERR_clear_error();
 180     return 1;
 181 }
 182
 183 static int module_run(const CONF *cnf, const char *name, const char *value,
 184                       unsigned long flags)
 185 {
 186     CONF_MODULE *md;
 187     int ret;
 188
 189     if (!RUN_ONCE(&load_builtin_modules, do_load_builtin_modules))
 190         return -1;
 191
 192     md = module_find(name);
 193
 194     /* Module not found: try to load DSO */
 195     if (!md && !(flags & CONF_MFLAGS_NO_DSO))
 196         md = module_load_dso(cnf, name, value);
 197
 198     if (!md) {
 199         if (!(flags & CONF_MFLAGS_SILENT)) {
 200             CONFerr(CONF_F_MODULE_RUN, CONF_R_UNKNOWN_MODULE_NAME);
 201             ERR_add_error_data(2, "module=", name);
 202         }
 203         return -1;
 204     }
 205
 206     ret = module_init(md, name, value, cnf);
 207
 208     if (ret <= 0) {
 209         if (!(flags & CONF_MFLAGS_SILENT)) {
 210             char rcode[DECIMAL_SIZE(ret) + 1];
 211
 212             CONFerr(CONF_F_MODULE_RUN, CONF_R_MODULE_INITIALIZATION_ERROR);
 213             BIO_snprintf(rcode, sizeof(rcode), "%-8d", ret);
 214             ERR_add_error_data(6, "module=", name, ", value=", value,
 215                                ", retcode=", rcode);
 216         }
 217     }
 218
 219     return ret;
 220 }
 221
 222 /* Load a module from a DSO */
 223 static CONF_MODULE *module_load_dso(const CONF *cnf,
 224                                     const char *name, const char *value)
 225 {
 226     DSO *dso = NULL;
 227     conf_init_func *ifunc;
 228     conf_finish_func *ffunc;
 229     const char *path = NULL;
 230     int errcode = 0;
 231     CONF_MODULE *md;
 232
 233     /* Look for alternative path in module section */
 234     path = NCONF_get_string(cnf, value, "path");
 235     if (path == NULL) {
 236         ERR_clear_error();
 237         path = name;
 238     }
 239     dso = DSO_load(NULL, path, NULL, 0);
 240     if (dso == NULL) {
 241         errcode = CONF_R_ERROR_LOADING_DSO;
 242         goto err;
 243     }
 244     ifunc = (conf_init_func *)DSO_bind_func(dso, DSO_mod_init_name);
 245     if (ifunc == NULL) {
 246         errcode = CONF_R_MISSING_INIT_FUNCTION;
 247         goto err;
 248     }
 249     ffunc = (conf_finish_func *)DSO_bind_func(dso, DSO_mod_finish_name);
 250     /* All OK, add module */
 251     md = module_add(dso, name, ifunc, ffunc);
 252
 253     if (md == NULL)
 254         goto err;
 255
 256     return md;
 257
 258  err:
 259     DSO_free(dso);
 260     CONFerr(CONF_F_MODULE_LOAD_DSO, errcode);
 261     ERR_add_error_data(4, "module=", name, ", path=", path);
 262     return NULL;
 263 }
 264
 265 /* add module to list */
 266 static CONF_MODULE *module_add(DSO *dso, const char *name,
 267                                conf_init_func *ifunc, conf_finish_func *ffunc)
 268 {
 269     CONF_MODULE *tmod = NULL;
 270     if (supported_modules == NULL)
 271         supported_modules = sk_CONF_MODULE_new_null();
 272     if (supported_modules == NULL)
 273         return NULL;
 274     if ((tmod = OPENSSL_zalloc(sizeof(*tmod))) == NULL) {
 275         CONFerr(CONF_F_MODULE_ADD, ERR_R_MALLOC_FAILURE);
 276         return NULL;
 277     }
 278
 279     tmod->dso = dso;
 280     tmod->name = OPENSSL_strdup(name);
 281     tmod->init = ifunc;
 282     tmod->finish = ffunc;
 283     if (tmod->name == NULL) {
 284         OPENSSL_free(tmod);
 285         return NULL;
 286     }
 287
 288     if (!sk_CONF_MODULE_push(supported_modules, tmod)) {
 289         OPENSSL_free(tmod->name);
 290         OPENSSL_free(tmod);
 291         return NULL;
 292     }
 293
 294     return tmod;
 295 }
 296
 297 /*
 298  * Find a module from the list. We allow module names of the form
 299  * modname.XXXX to just search for modname to allow the same module to be
 300  * initialized more than once.
 301  */
 302
 303 static CONF_MODULE *module_find(const char *name)
 304 {
 305     CONF_MODULE *tmod;
 306     int i, nchar;
 307     char *p;
 308     p = strrchr(name, '.');
 309
 310     if (p)
 311         nchar = p - name;
 312     else
 313         nchar = strlen(name);
 314
 315     for (i = 0; i < sk_CONF_MODULE_num(supported_modules); i++) {
 316         tmod = sk_CONF_MODULE_value(supported_modules, i);
 317         if (strncmp(tmod->name, name, nchar) == 0)
 318             return tmod;
 319     }
 320
 321     return NULL;
 322
 323 }
 324
 325 /* initialize a module */
 326 static int module_init(CONF_MODULE *pmod, const char *name, const char *value,
 327                        const CONF *cnf)
 328 {
 329     int ret = 1;
 330     int init_called = 0;
 331     CONF_IMODULE *imod = NULL;
 332
 333     /* Otherwise add initialized module to list */
 334     imod = OPENSSL_malloc(sizeof(*imod));
 335     if (imod == NULL)
 336         goto err;
 337
 338     imod->pmod = pmod;
 339     imod->name = OPENSSL_strdup(name);
 340     imod->value = OPENSSL_strdup(value);
 341     imod->usr_data = NULL;
 342
 343     if (!imod->name || !imod->value)
 344         goto memerr;
 345
 346     /* Try to initialize module */
 347     if (pmod->init) {
 348         ret = pmod->init(imod, cnf);
 349         init_called = 1;
 350         /* Error occurred, exit */
 351         if (ret <= 0)
 352             goto err;
 353     }
 354
 355     if (initialized_modules == NULL) {
 356         initialized_modules = sk_CONF_IMODULE_new_null();
 357         if (!initialized_modules) {
 358             CONFerr(CONF_F_MODULE_INIT, ERR_R_MALLOC_FAILURE);
 359             goto err;
 360         }
 361     }
 362
 363     if (!sk_CONF_IMODULE_push(initialized_modules, imod)) {
 364         CONFerr(CONF_F_MODULE_INIT, ERR_R_MALLOC_FAILURE);
 365         goto err;
 366     }
 367
 368     pmod->links++;
 369
 370     return ret;
 371
 372  err:
 373
 374     /* We've started the module so we'd better finish it */
 375     if (pmod->finish && init_called)
 376         pmod->finish(imod);
 377
 378  memerr:
 379     if (imod) {
 380         OPENSSL_free(imod->name);
 381         OPENSSL_free(imod->value);
 382         OPENSSL_free(imod);
 383     }
 384
 385     return -1;
 386
 387 }
 388
 389 /*
 390  * Unload any dynamic modules that have a link count of zero: i.e. have no
 391  * active initialized modules. If 'all' is set then all modules are unloaded
 392  * including static ones.
 393  */
 394
 395 void CONF_modules_unload(int all)
 396 {
 397     int i;
 398     CONF_MODULE *md;
 399     CONF_modules_finish();
 400     /* unload modules in reverse order */
 401     for (i = sk_CONF_MODULE_num(supported_modules) - 1; i >= 0; i--) {
 402         md = sk_CONF_MODULE_value(supported_modules, i);
 403         /* If static or in use and 'all' not set ignore it */
 404         if (((md->links > 0) || !md->dso) && !all)
 405             continue;
 406         /* Since we're working in reverse this is OK */
 407         (void)sk_CONF_MODULE_delete(supported_modules, i);
 408         module_free(md);
 409     }
 410     if (sk_CONF_MODULE_num(supported_modules) == 0) {
 411         sk_CONF_MODULE_free(supported_modules);
 412         supported_modules = NULL;
 413     }
 414 }
 415
 416 /* unload a single module */
 417 static void module_free(CONF_MODULE *md)
 418 {
 419     DSO_free(md->dso);
 420     OPENSSL_free(md->name);
 421     OPENSSL_free(md);
 422 }
 423
 424 /* finish and free up all modules instances */
 425
 426 void CONF_modules_finish(void)
 427 {
 428     CONF_IMODULE *imod;
 429     while (sk_CONF_IMODULE_num(initialized_modules) > 0) {
 430         imod = sk_CONF_IMODULE_pop(initialized_modules);
 431         module_finish(imod);
 432     }
 433     sk_CONF_IMODULE_free(initialized_modules);
 434     initialized_modules = NULL;
 435 }
 436
 437 /* finish a module instance */
 438
 439 static void module_finish(CONF_IMODULE *imod)
 440 {
 441     if (!imod)
 442         return;
 443     if (imod->pmod->finish)
 444         imod->pmod->finish(imod);
 445     imod->pmod->links--;
 446     OPENSSL_free(imod->name);
 447     OPENSSL_free(imod->value);
 448     OPENSSL_free(imod);
 449 }
 450
 451 /* Add a static module to OpenSSL */
 452
 453 int CONF_module_add(const char *name, conf_init_func *ifunc,
 454                     conf_finish_func *ffunc)
 455 {
 456     if (module_add(NULL, name, ifunc, ffunc))
 457         return 1;
 458     else
 459         return 0;
 460 }
 461
 462 void conf_modules_free_int(void)
 463 {
 464     CONF_modules_finish();
 465     CONF_modules_unload(1);
 466 }
 467
 468 /* Utility functions */
 469
 470 const char *CONF_imodule_get_name(const CONF_IMODULE *md)
 471 {
 472     return md->name;
 473 }
 474
 475 const char *CONF_imodule_get_value(const CONF_IMODULE *md)
 476 {
 477     return md->value;
 478 }
 479
 480 void *CONF_imodule_get_usr_data(const CONF_IMODULE *md)
 481 {
 482     return md->usr_data;
 483 }
 484
 485 void CONF_imodule_set_usr_data(CONF_IMODULE *md, void *usr_data)
 486 {
 487     md->usr_data = usr_data;
 488 }
 489
 490 CONF_MODULE *CONF_imodule_get_module(const CONF_IMODULE *md)
 491 {
 492     return md->pmod;
 493 }
 494
 495 unsigned long CONF_imodule_get_flags(const CONF_IMODULE *md)
 496 {
 497     return md->flags;
 498 }
 499
 500 void CONF_imodule_set_flags(CONF_IMODULE *md, unsigned long flags)
 501 {
 502     md->flags = flags;
 503 }
 504
 505 void *CONF_module_get_usr_data(CONF_MODULE *pmod)
 506 {
 507     return pmod->usr_data;
 508 }
 509
 510 void CONF_module_set_usr_data(CONF_MODULE *pmod, void *usr_data)
 511 {
 512     pmod->usr_data = usr_data;
 513 }
 514
 515 /* Return default config file name */
 516
 517 char *CONF_get1_default_config_file(void)
 518 {
 519     char *file, *sep = "";
 520     int len;
 521
 522     if ((file = ossl_safe_getenv("OPENSSL_CONF")) != NULL)
 523         return OPENSSL_strdup(file);
 524
 525     len = strlen(X509_get_default_cert_area());
 526 #ifndef OPENSSL_SYS_VMS
 527     len++;
 528     sep = "/";
 529 #endif
 530     len += strlen(OPENSSL_CONF);
 531
 532     file = OPENSSL_malloc(len + 1);
 533
 534     if (file == NULL)
 535         return NULL;
 536     BIO_snprintf(file, len + 1, "%s%s%s", X509_get_default_cert_area(),
 537                  sep, OPENSSL_CONF);
 538
 539     return file;
 540 }
 541
 542 /*
 543  * This function takes a list separated by 'sep' and calls the callback
 544  * function giving the start and length of each member optionally stripping
 545  * leading and trailing whitespace. This can be used to parse comma separated
 546  * lists for example.
 547  */
 548
 549 int CONF_parse_list(const char *list_, int sep, int nospc,
 550                     int (*list_cb) (const char *elem, int len, void *usr),
 551                     void *arg)
 552 {
 553     int ret;
 554     const char *lstart, *tmpend, *p;
 555
 556     if (list_ == NULL) {
 557         CONFerr(CONF_F_CONF_PARSE_LIST, CONF_R_LIST_CANNOT_BE_NULL);
 558         return 0;
 559     }
 560
 561     lstart = list_;
 562     for (;;) {
 563         if (nospc) {
 564             while (*lstart && isspace((unsigned char)*lstart))
 565                 lstart++;
 566         }
 567         p = strchr(lstart, sep);
 568         if (p == lstart || *lstart == '\0')
 569             ret = list_cb(NULL, 0, arg);
 570         else {
 571             if (p)
 572                 tmpend = p - 1;
 573             else
 574                 tmpend = lstart + strlen(lstart) - 1;
 575             if (nospc) {
 576                 while (isspace((unsigned char)*tmpend))
 577                     tmpend--;
 578             }
 579             ret = list_cb(lstart, tmpend - lstart + 1, arg);
 580         }
 581         if (ret <= 0)
 582             return ret;
 583         if (p == NULL)
 584             return 1;
 585         lstart = p + 1;
 586     }
 587 }