crypto/provider_conf.c

   1 /*
   2  * Copyright 2019-2023 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 #include <string.h>
  11 #include <openssl/trace.h>
  12 #include <openssl/err.h>
  13 #include <openssl/conf.h>
  14 #include <openssl/safestack.h>
  15 #include <openssl/provider.h>
  16 #include "internal/provider.h"
  17 #include "internal/cryptlib.h"
  18 #include "provider_local.h"
  19 #include "crypto/context.h"
  20
  21 DEFINE_STACK_OF(OSSL_PROVIDER)
  22
  23 /* PROVIDER config module */
  24
  25 typedef struct {
  26     CRYPTO_RWLOCK *lock;
  27     STACK_OF(OSSL_PROVIDER) *activated_providers;
  28 } PROVIDER_CONF_GLOBAL;
  29
  30 void *ossl_prov_conf_ctx_new(OSSL_LIB_CTX *libctx)
  31 {
  32     PROVIDER_CONF_GLOBAL *pcgbl = OPENSSL_zalloc(sizeof(*pcgbl));
  33
  34     if (pcgbl == NULL)
  35         return NULL;
  36
  37     pcgbl->lock = CRYPTO_THREAD_lock_new();
  38     if (pcgbl->lock == NULL) {
  39         OPENSSL_free(pcgbl);
  40         return NULL;
  41     }
  42
  43     return pcgbl;
  44 }
  45
  46 void ossl_prov_conf_ctx_free(void *vpcgbl)
  47 {
  48     PROVIDER_CONF_GLOBAL *pcgbl = vpcgbl;
  49
  50     sk_OSSL_PROVIDER_pop_free(pcgbl->activated_providers,
  51                               ossl_provider_free);
  52
  53     OSSL_TRACE(CONF, "Cleaned up providers\n");
  54     CRYPTO_THREAD_lock_free(pcgbl->lock);
  55     OPENSSL_free(pcgbl);
  56 }
  57
  58 static const char *skip_dot(const char *name)
  59 {
  60     const char *p = strchr(name, '.');
  61
  62     if (p != NULL)
  63         return p + 1;
  64     return name;
  65 }
  66
  67 /*
  68  * Parse the provider params section
  69  * Returns:
  70  * 1 for success
  71  * 0 for non-fatal errors
  72  * < 0 for fatal errors
  73  */
  74 static int provider_conf_params_internal(OSSL_PROVIDER *prov,
  75                                          OSSL_PROVIDER_INFO *provinfo,
  76                                          const char *name, const char *value,
  77                                          const CONF *cnf,
  78                                          STACK_OF(OPENSSL_CSTRING) *visited)
  79 {
  80     STACK_OF(CONF_VALUE) *sect;
  81     int ok = 1;
  82     int rc = 0;
  83
  84     sect = NCONF_get_section(cnf, value);
  85     if (sect != NULL) {
  86         int i;
  87         char buffer[512];
  88         size_t buffer_len = 0;
  89
  90         OSSL_TRACE1(CONF, "Provider params: start section %s\n", value);
  91
  92         /*
  93          * Check to see if the provided section value has already
  94          * been visited.  If it has, then we have a recursive lookup
  95          * in the configuration which isn't valid.  As such we should error
  96          * out
  97          */
  98         for (i = 0; i < sk_OPENSSL_CSTRING_num(visited); i++) {
  99             if (sk_OPENSSL_CSTRING_value(visited, i) == value) {
 100                 ERR_raise(ERR_LIB_CONF, CONF_R_RECURSIVE_SECTION_REFERENCE);
 101                 return -1;
 102             }
 103         }
 104
 105         /*
 106          * We've not visited this node yet, so record it on the stack
 107          */
 108         if (!sk_OPENSSL_CSTRING_push(visited, value))
 109             return -1;
 110
 111         if (name != NULL) {
 112             OPENSSL_strlcpy(buffer, name, sizeof(buffer));
 113             OPENSSL_strlcat(buffer, ".", sizeof(buffer));
 114             buffer_len = strlen(buffer);
 115         }
 116
 117         for (i = 0; i < sk_CONF_VALUE_num(sect); i++) {
 118             CONF_VALUE *sectconf = sk_CONF_VALUE_value(sect, i);
 119
 120             if (buffer_len + strlen(sectconf->name) >= sizeof(buffer)) {
 121                 sk_OPENSSL_CSTRING_pop(visited);
 122                 return -1;
 123             }
 124             buffer[buffer_len] = '\0';
 125             OPENSSL_strlcat(buffer, sectconf->name, sizeof(buffer));
 126             rc = provider_conf_params_internal(prov, provinfo, buffer,
 127                                                sectconf->value, cnf, visited);
 128             if (rc < 0) {
 129                 sk_OPENSSL_CSTRING_pop(visited);
 130                 return rc;
 131             }
 132         }
 133         sk_OPENSSL_CSTRING_pop(visited);
 134
 135         OSSL_TRACE1(CONF, "Provider params: finish section %s\n", value);
 136     } else {
 137         OSSL_TRACE2(CONF, "Provider params: %s = %s\n", name, value);
 138         if (prov != NULL)
 139             ok = ossl_provider_add_parameter(prov, name, value);
 140         else
 141             ok = ossl_provider_info_add_parameter(provinfo, name, value);
 142     }
 143
 144     return ok;
 145 }
 146
 147 /*
 148  * recursively parse the provider configuration section
 149  * of the config file.
 150  * Returns
 151  * 1 on success
 152  * 0 on non-fatal error
 153  * < 0 on fatal errors
 154  */
 155 static int provider_conf_params(OSSL_PROVIDER *prov,
 156                                 OSSL_PROVIDER_INFO *provinfo,
 157                                 const char *name, const char *value,
 158                                 const CONF *cnf)
 159 {
 160     int rc;
 161     STACK_OF(OPENSSL_CSTRING) *visited = sk_OPENSSL_CSTRING_new_null();
 162
 163     if (visited == NULL)
 164         return -1;
 165
 166     rc = provider_conf_params_internal(prov, provinfo, name,
 167                                        value, cnf, visited);
 168
 169     sk_OPENSSL_CSTRING_free(visited);
 170
 171     return rc;
 172 }
 173
 174 static int prov_already_activated(const char *name,
 175                                   STACK_OF(OSSL_PROVIDER) *activated)
 176 {
 177     int i, max;
 178
 179     if (activated == NULL)
 180         return 0;
 181
 182     max = sk_OSSL_PROVIDER_num(activated);
 183     for (i = 0; i < max; i++) {
 184         OSSL_PROVIDER *tstprov = sk_OSSL_PROVIDER_value(activated, i);
 185
 186         if (strcmp(OSSL_PROVIDER_get0_name(tstprov), name) == 0) {
 187             return 1;
 188         }
 189     }
 190
 191     return 0;
 192 }
 193
 194 /*
 195  * Attempt to activate a provider
 196  * Returns:
 197  * 1 on successful activation
 198  * 0 on failed activation for non-fatal error
 199  * < 0 on failed activation for fatal errors
 200  */
 201 static int provider_conf_activate(OSSL_LIB_CTX *libctx, const char *name,
 202                                   const char *value, const char *path,
 203                                   int soft, const CONF *cnf)
 204 {
 205     PROVIDER_CONF_GLOBAL *pcgbl
 206         = ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_PROVIDER_CONF_INDEX);
 207     OSSL_PROVIDER *prov = NULL, *actual = NULL;
 208     int ok = 0;
 209
 210     if (pcgbl == NULL || !CRYPTO_THREAD_write_lock(pcgbl->lock)) {
 211         ERR_raise(ERR_LIB_CRYPTO, ERR_R_INTERNAL_ERROR);
 212         return -1;
 213     }
 214     if (!prov_already_activated(name, pcgbl->activated_providers)) {
 215         /*
 216         * There is an attempt to activate a provider, so we should disable
 217         * loading of fallbacks. Otherwise a misconfiguration could mean the
 218         * intended provider does not get loaded. Subsequent fetches could
 219         * then fallback to the default provider - which may be the wrong
 220         * thing.
 221         */
 222         if (!ossl_provider_disable_fallback_loading(libctx)) {
 223             CRYPTO_THREAD_unlock(pcgbl->lock);
 224             ERR_raise(ERR_LIB_CRYPTO, ERR_R_INTERNAL_ERROR);
 225             return -1;
 226         }
 227         prov = ossl_provider_find(libctx, name, 1);
 228         if (prov == NULL)
 229             prov = ossl_provider_new(libctx, name, NULL, NULL, 1);
 230         if (prov == NULL) {
 231             CRYPTO_THREAD_unlock(pcgbl->lock);
 232             if (soft)
 233                 ERR_clear_error();
 234             return (soft == 0) ? -1 : 0;
 235         }
 236
 237         if (path != NULL)
 238             ossl_provider_set_module_path(prov, path);
 239
 240         ok = provider_conf_params(prov, NULL, NULL, value, cnf);
 241
 242         if (ok == 1) {
 243             if (!ossl_provider_activate(prov, 1, 0)) {
 244                 ok = 0;
 245             } else if (!ossl_provider_add_to_store(prov, &actual, 0)) {
 246                 ossl_provider_deactivate(prov, 1);
 247                 ok = 0;
 248             } else if (actual != prov
 249                        && !ossl_provider_activate(actual, 1, 0)) {
 250                 ossl_provider_free(actual);
 251                 ok = 0;
 252             } else {
 253                 if (pcgbl->activated_providers == NULL)
 254                     pcgbl->activated_providers = sk_OSSL_PROVIDER_new_null();
 255                 if (pcgbl->activated_providers == NULL
 256                     || !sk_OSSL_PROVIDER_push(pcgbl->activated_providers,
 257                                               actual)) {
 258                     ossl_provider_deactivate(actual, 1);
 259                     ossl_provider_free(actual);
 260                     ok = 0;
 261                 } else {
 262                     ok = 1;
 263                 }
 264             }
 265         }
 266
 267         if (ok <= 0)
 268             ossl_provider_free(prov);
 269     }
 270     CRYPTO_THREAD_unlock(pcgbl->lock);
 271
 272     return ok;
 273 }
 274
 275 static int provider_conf_load(OSSL_LIB_CTX *libctx, const char *name,
 276                               const char *value, const CONF *cnf)
 277 {
 278     int i;
 279     STACK_OF(CONF_VALUE) *ecmds;
 280     int soft = 0;
 281     const char *path = NULL;
 282     long activate = 0;
 283     int ok = 0;
 284     int added = 0;
 285
 286     name = skip_dot(name);
 287     OSSL_TRACE1(CONF, "Configuring provider %s\n", name);
 288     /* Value is a section containing PROVIDER commands */
 289     ecmds = NCONF_get_section(cnf, value);
 290
 291     if (!ecmds) {
 292         ERR_raise_data(ERR_LIB_CRYPTO, CRYPTO_R_PROVIDER_SECTION_ERROR,
 293                        "section=%s not found", value);
 294         return 0;
 295     }
 296
 297     /* Find the needed data first */
 298     for (i = 0; i < sk_CONF_VALUE_num(ecmds); i++) {
 299         CONF_VALUE *ecmd = sk_CONF_VALUE_value(ecmds, i);
 300         const char *confname = skip_dot(ecmd->name);
 301         const char *confvalue = ecmd->value;
 302
 303         OSSL_TRACE2(CONF, "Provider command: %s = %s\n",
 304                     confname, confvalue);
 305
 306         /* First handle some special pseudo confs */
 307
 308         /* Override provider name to use */
 309         if (strcmp(confname, "identity") == 0) {
 310             name = confvalue;
 311         } else if (strcmp(confname, "soft_load") == 0) {
 312             soft = 1;
 313         /* Load a dynamic PROVIDER */
 314         } else if (strcmp(confname, "module") == 0) {
 315             path = confvalue;
 316         } else if (strcmp(confname, "activate") == 0) {
 317             if (confvalue == NULL) {
 318                 ERR_raise_data(ERR_LIB_CRYPTO, CRYPTO_R_PROVIDER_SECTION_ERROR,
 319                                "section=%s activate set to unrecognized value",
 320                                value);
 321                 return 0;
 322             }
 323             if ((strcmp(confvalue, "1") == 0)
 324                 || (strcmp(confvalue, "yes") == 0)
 325                 || (strcmp(confvalue, "YES") == 0)
 326                 || (strcmp(confvalue, "true") == 0)
 327                 || (strcmp(confvalue, "TRUE") == 0)
 328                 || (strcmp(confvalue, "on") == 0)
 329                 || (strcmp(confvalue, "ON") == 0)) {
 330                 activate = 1;
 331             } else if ((strcmp(confvalue, "0") == 0)
 332                        || (strcmp(confvalue, "no") == 0)
 333                        || (strcmp(confvalue, "NO") == 0)
 334                        || (strcmp(confvalue, "false") == 0)
 335                        || (strcmp(confvalue, "FALSE") == 0)
 336                        || (strcmp(confvalue, "off") == 0)
 337                        || (strcmp(confvalue, "OFF") == 0)) {
 338                 activate = 0;
 339             } else {
 340                 ERR_raise_data(ERR_LIB_CRYPTO, CRYPTO_R_PROVIDER_SECTION_ERROR,
 341                                "section=%s activate set to unrecognized value",
 342                                value);
 343                 return 0;
 344             }
 345         }
 346     }
 347
 348     if (activate) {
 349         ok = provider_conf_activate(libctx, name, value, path, soft, cnf);
 350     } else {
 351         OSSL_PROVIDER_INFO entry;
 352
 353         memset(&entry, 0, sizeof(entry));
 354         ok = 1;
 355         if (name != NULL) {
 356             entry.name = OPENSSL_strdup(name);
 357             if (entry.name == NULL)
 358                 ok = 0;
 359         }
 360         if (ok && path != NULL) {
 361             entry.path = OPENSSL_strdup(path);
 362             if (entry.path == NULL)
 363                 ok = 0;
 364         }
 365         if (ok)
 366             ok = provider_conf_params(NULL, &entry, NULL, value, cnf);
 367         if (ok >= 1 && (entry.path != NULL || entry.parameters != NULL)) {
 368             ok = ossl_provider_info_add_to_store(libctx, &entry);
 369             added = 1;
 370         }
 371         if (added == 0)
 372             ossl_provider_info_clear(&entry);
 373     }
 374
 375     /*
 376      * Provider activation returns a tristate:
 377      * 1 for successful activation
 378      * 0 for non-fatal activation failure
 379      * < 0 for fatal activation failure
 380      * We return success (1) for activation, (1) for non-fatal activation
 381      * failure, and (0) for fatal activation failure
 382      */
 383     return ok >= 0;
 384 }
 385
 386 static int provider_conf_init(CONF_IMODULE *md, const CONF *cnf)
 387 {
 388     STACK_OF(CONF_VALUE) *elist;
 389     CONF_VALUE *cval;
 390     int i;
 391
 392     OSSL_TRACE1(CONF, "Loading providers module: section %s\n",
 393                 CONF_imodule_get_value(md));
 394
 395     /* Value is a section containing PROVIDERs to configure */
 396     elist = NCONF_get_section(cnf, CONF_imodule_get_value(md));
 397
 398     if (!elist) {
 399         ERR_raise(ERR_LIB_CRYPTO, CRYPTO_R_PROVIDER_SECTION_ERROR);
 400         return 0;
 401     }
 402
 403     for (i = 0; i < sk_CONF_VALUE_num(elist); i++) {
 404         cval = sk_CONF_VALUE_value(elist, i);
 405         if (!provider_conf_load(NCONF_get0_libctx((CONF *)cnf),
 406                                 cval->name, cval->value, cnf))
 407             return 0;
 408     }
 409
 410     return 1;
 411 }
 412
 413 void ossl_provider_add_conf_module(void)
 414 {
 415     OSSL_TRACE(CONF, "Adding config module 'providers'\n");
 416     CONF_module_add("providers", provider_conf_init, NULL);
 417 }