crypto/conf/conf_mod.c - third_party/openssl - Git at Google

 /*
  * Copyright 2002-2021 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the Apache License 2.0 (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
  * in the file LICENSE in the source distribution or at
  * https://www.openssl.org/source/license.html
  */

 /* We need to use some engine deprecated APIs */
 #define OPENSSL_SUPPRESS_DEPRECATED

 #include "internal/cryptlib.h"
 #include <stdio.h>
 #include <ctype.h>
 #include <openssl/crypto.h>
 #include "internal/conf.h"
 #include <openssl/conf_api.h>
 #include "internal/dso.h"
 #include "internal/thread_once.h"
 #include <openssl/x509.h>
 #include <openssl/trace.h>
 #include <openssl/engine.h>
 #include "conf_local.h"

 DEFINE_STACK_OF(CONF_MODULE)
 DEFINE_STACK_OF(CONF_IMODULE)

 #define DSO_mod_init_name "OPENSSL_init"
 #define DSO_mod_finish_name "OPENSSL_finish"

 /*
  * This structure contains a data about supported modules. entries in this
  * table correspond to either dynamic or static modules.
  */

 struct conf_module_st {
     /* DSO of this module or NULL if static */
     DSO *dso;
     /* Name of the module */
     char *name;
     /* Init function */
     conf_init_func *init;
     /* Finish function */
     conf_finish_func *finish;
     /* Number of successfully initialized modules */
     int links;
     void *usr_data;
 };

 /*
  * This structure contains information about modules that have been
  * successfully initialized. There may be more than one entry for a given
  * module.
  */

 struct conf_imodule_st {
     CONF_MODULE *pmod;
     char *name;
     char *value;
     unsigned long flags;
     void *usr_data;
 };

 static STACK_OF(CONF_MODULE) *supported_modules = NULL;
 static STACK_OF(CONF_IMODULE) *initialized_modules = NULL;

 static CRYPTO_ONCE load_builtin_modules = CRYPTO_ONCE_STATIC_INIT;

 static void module_free(CONF_MODULE *md);
 static void module_finish(CONF_IMODULE *imod);
 static int module_run(const CONF *cnf, const char *name, const char *value,
                       unsigned long flags);
 static CONF_MODULE *module_add(DSO *dso, const char *name,
                                conf_init_func *ifunc,
                                conf_finish_func *ffunc);
 static CONF_MODULE *module_find(const char *name);
 static int module_init(CONF_MODULE *pmod, const char *name, const char *value,
                        const CONF *cnf);
 static CONF_MODULE *module_load_dso(const CONF *cnf, const char *name,
                                     const char *value);

 static int conf_diagnostics(const CONF *cnf)
 {
     return _CONF_get_number(cnf, NULL, "config_diagnostics") != 0;
 }

 /* Main function: load modules from a CONF structure */

 int CONF_modules_load(const CONF *cnf, const char *appname,
                       unsigned long flags)
 {
     STACK_OF(CONF_VALUE) *values;
     CONF_VALUE *vl;
     char *vsection = NULL;
     int ret, i;

     if (!cnf)
         return 1;

     if (conf_diagnostics(cnf))
         flags &= ~(CONF_MFLAGS_IGNORE_ERRORS
                    | CONF_MFLAGS_IGNORE_RETURN_CODES
                    | CONF_MFLAGS_SILENT
                    | CONF_MFLAGS_IGNORE_MISSING_FILE);

     ERR_set_mark();
     if (appname)
         vsection = NCONF_get_string(cnf, NULL, appname);

     if (!appname || (!vsection && (flags & CONF_MFLAGS_DEFAULT_SECTION)))
         vsection = NCONF_get_string(cnf, NULL, "openssl_conf");

     if (!vsection) {
         ERR_pop_to_mark();
         return 1;
     }

     OSSL_TRACE1(CONF, "Configuration in section %s\n", vsection);
     values = NCONF_get_section(cnf, vsection);

     if (values == NULL) {
         if (!(flags & CONF_MFLAGS_SILENT)) {
             ERR_clear_last_mark();
             ERR_raise_data(ERR_LIB_CONF,
                            CONF_R_OPENSSL_CONF_REFERENCES_MISSING_SECTION,
                            "openssl_conf=%s", vsection);
         } else {
             ERR_pop_to_mark();
         }
         return 0;
     }
     ERR_pop_to_mark();

     for (i = 0; i < sk_CONF_VALUE_num(values); i++) {
         vl = sk_CONF_VALUE_value(values, i);
         ERR_set_mark();
         ret = module_run(cnf, vl->name, vl->value, flags);
         OSSL_TRACE3(CONF, "Running module %s (%s) returned %d\n",
                     vl->name, vl->value, ret);
         if (ret <= 0)
             if (!(flags & CONF_MFLAGS_IGNORE_ERRORS)) {
                 ERR_clear_last_mark();
                 return ret;
             }
         ERR_pop_to_mark();
     }

     return 1;

 }

 int CONF_modules_load_file_ex(OSSL_LIB_CTX *libctx, const char *filename,
                               const char *appname, unsigned long flags)
 {
     char *file = NULL;
     CONF *conf = NULL;
     int ret = 0, diagnostics = 0;

     if (filename == NULL) {
         file = CONF_get1_default_config_file();
         if (file == NULL)
             goto err;
     } else {
         file = (char *)filename;
     }

     ERR_set_mark();
     conf = NCONF_new_ex(libctx, NULL);
     if (conf == NULL)
         goto err;

     if (NCONF_load(conf, file, NULL) <= 0) {
         if ((flags & CONF_MFLAGS_IGNORE_MISSING_FILE) &&
             (ERR_GET_REASON(ERR_peek_last_error()) == CONF_R_NO_SUCH_FILE)) {
             ret = 1;
         }
         goto err;
     }

     ret = CONF_modules_load(conf, appname, flags);
     diagnostics = conf_diagnostics(conf);

  err:
     if (filename == NULL)
         OPENSSL_free(file);
     NCONF_free(conf);

     if ((flags & CONF_MFLAGS_IGNORE_RETURN_CODES) != 0 && !diagnostics)
         ret = 1;

     if (ret > 0)
         ERR_pop_to_mark();
     else
         ERR_clear_last_mark();

     return ret;
 }

 int CONF_modules_load_file(const char *filename,
                            const char *appname, unsigned long flags)
 {
     return CONF_modules_load_file_ex(NULL, filename, appname, flags);
 }

 DEFINE_RUN_ONCE_STATIC(do_load_builtin_modules)
 {
     OPENSSL_load_builtin_modules();
 #ifndef OPENSSL_NO_ENGINE
     /* Need to load ENGINEs */
     ENGINE_load_builtin_engines();
 #endif
     return 1;
 }

 static int module_run(const CONF *cnf, const char *name, const char *value,
                       unsigned long flags)
 {
     CONF_MODULE *md;
     int ret;

     if (!RUN_ONCE(&load_builtin_modules, do_load_builtin_modules))
         return -1;

     md = module_find(name);

     /* Module not found: try to load DSO */
     if (!md && !(flags & CONF_MFLAGS_NO_DSO))
         md = module_load_dso(cnf, name, value);

     if (!md) {
         if (!(flags & CONF_MFLAGS_SILENT)) {
             ERR_raise_data(ERR_LIB_CONF, CONF_R_UNKNOWN_MODULE_NAME,
                            "module=%s", name);
         }
         return -1;
     }

     ret = module_init(md, name, value, cnf);

     if (ret <= 0) {
         if (!(flags & CONF_MFLAGS_SILENT))
             ERR_raise_data(ERR_LIB_CONF, CONF_R_MODULE_INITIALIZATION_ERROR,
                            "module=%s, value=%s retcode=%-8d",
                            name, value, ret);
     }

     return ret;
 }

 /* Load a module from a DSO */
 static CONF_MODULE *module_load_dso(const CONF *cnf,
                                     const char *name, const char *value)
 {
     DSO *dso = NULL;
     conf_init_func *ifunc;
     conf_finish_func *ffunc;
     const char *path = NULL;
     int errcode = 0;
     CONF_MODULE *md;

     /* Look for alternative path in module section */
     path = _CONF_get_string(cnf, value, "path");
     if (path == NULL) {
         path = name;
     }
     dso = DSO_load(NULL, path, NULL, 0);
     if (dso == NULL) {
         errcode = CONF_R_ERROR_LOADING_DSO;
         goto err;
     }
     ifunc = (conf_init_func *)DSO_bind_func(dso, DSO_mod_init_name);
     if (ifunc == NULL) {
         errcode = CONF_R_MISSING_INIT_FUNCTION;
         goto err;
     }
     ffunc = (conf_finish_func *)DSO_bind_func(dso, DSO_mod_finish_name);
     /* All OK, add module */
     md = module_add(dso, name, ifunc, ffunc);

     if (md == NULL)
         goto err;

     return md;

  err:
     DSO_free(dso);
     ERR_raise_data(ERR_LIB_CONF, errcode, "module=%s, path=%s", name, path);
     return NULL;
 }

 /* add module to list */
 static CONF_MODULE *module_add(DSO *dso, const char *name,
                                conf_init_func *ifunc, conf_finish_func *ffunc)
 {
     CONF_MODULE *tmod = NULL;
     if (supported_modules == NULL)
         supported_modules = sk_CONF_MODULE_new_null();
     if (supported_modules == NULL)
         return NULL;
     if ((tmod = OPENSSL_zalloc(sizeof(*tmod))) == NULL) {
         ERR_raise(ERR_LIB_CONF, ERR_R_MALLOC_FAILURE);
         return NULL;
     }

     tmod->dso = dso;
     tmod->name = OPENSSL_strdup(name);
     tmod->init = ifunc;
     tmod->finish = ffunc;
     if (tmod->name == NULL) {
         OPENSSL_free(tmod);
         return NULL;
     }

     if (!sk_CONF_MODULE_push(supported_modules, tmod)) {
         OPENSSL_free(tmod->name);
         OPENSSL_free(tmod);
         return NULL;
     }

     return tmod;
 }

 /*
  * Find a module from the list. We allow module names of the form
  * modname.XXXX to just search for modname to allow the same module to be
  * initialized more than once.
  */

 static CONF_MODULE *module_find(const char *name)
 {
     CONF_MODULE *tmod;
     int i, nchar;
     char *p;
     p = strrchr(name, '.');

     if (p)
         nchar = p - name;
     else
         nchar = strlen(name);

     for (i = 0; i < sk_CONF_MODULE_num(supported_modules); i++) {
         tmod = sk_CONF_MODULE_value(supported_modules, i);
         if (strncmp(tmod->name, name, nchar) == 0)
             return tmod;
     }

     return NULL;

 }

 /* initialize a module */
 static int module_init(CONF_MODULE *pmod, const char *name, const char *value,
                        const CONF *cnf)
 {
     int ret = 1;
     int init_called = 0;
     CONF_IMODULE *imod = NULL;

     /* Otherwise add initialized module to list */
     imod = OPENSSL_malloc(sizeof(*imod));
     if (imod == NULL)
         goto err;

     imod->pmod = pmod;
     imod->name = OPENSSL_strdup(name);
     imod->value = OPENSSL_strdup(value);
     imod->usr_data = NULL;

     if (!imod->name || !imod->value)
         goto memerr;

     /* Try to initialize module */
     if (pmod->init) {
         ret = pmod->init(imod, cnf);
         init_called = 1;
         /* Error occurred, exit */
         if (ret <= 0)
             goto err;
     }

     if (initialized_modules == NULL) {
         initialized_modules = sk_CONF_IMODULE_new_null();
         if (!initialized_modules) {
             ERR_raise(ERR_LIB_CONF, ERR_R_MALLOC_FAILURE);
             goto err;
         }
     }

     if (!sk_CONF_IMODULE_push(initialized_modules, imod)) {
         ERR_raise(ERR_LIB_CONF, ERR_R_MALLOC_FAILURE);
         goto err;
     }

     pmod->links++;

     return ret;

  err:

     /* We've started the module so we'd better finish it */
     if (pmod->finish && init_called)
         pmod->finish(imod);

  memerr:
     if (imod) {
         OPENSSL_free(imod->name);
         OPENSSL_free(imod->value);
         OPENSSL_free(imod);
     }

     return -1;

 }

 /*
  * Unload any dynamic modules that have a link count of zero: i.e. have no
  * active initialized modules. If 'all' is set then all modules are unloaded
  * including static ones.
  */

 void CONF_modules_unload(int all)
 {
     int i;
     CONF_MODULE *md;
     CONF_modules_finish();
     /* unload modules in reverse order */
     for (i = sk_CONF_MODULE_num(supported_modules) - 1; i >= 0; i--) {
         md = sk_CONF_MODULE_value(supported_modules, i);
         /* If static or in use and 'all' not set ignore it */
         if (((md->links > 0) || !md->dso) && !all)
             continue;
         /* Since we're working in reverse this is OK */
         (void)sk_CONF_MODULE_delete(supported_modules, i);
         module_free(md);
     }
     if (sk_CONF_MODULE_num(supported_modules) == 0) {
         sk_CONF_MODULE_free(supported_modules);
         supported_modules = NULL;
     }
 }

 /* unload a single module */
 static void module_free(CONF_MODULE *md)
 {
     DSO_free(md->dso);
     OPENSSL_free(md->name);
     OPENSSL_free(md);
 }

 /* finish and free up all modules instances */

 void CONF_modules_finish(void)
 {
     CONF_IMODULE *imod;
     while (sk_CONF_IMODULE_num(initialized_modules) > 0) {
         imod = sk_CONF_IMODULE_pop(initialized_modules);
         module_finish(imod);
     }
     sk_CONF_IMODULE_free(initialized_modules);
     initialized_modules = NULL;
 }

 /* finish a module instance */

 static void module_finish(CONF_IMODULE *imod)
 {
     if (!imod)
         return;
     if (imod->pmod->finish)
         imod->pmod->finish(imod);
     imod->pmod->links--;
     OPENSSL_free(imod->name);
     OPENSSL_free(imod->value);
     OPENSSL_free(imod);
 }

 /* Add a static module to OpenSSL */

 int CONF_module_add(const char *name, conf_init_func *ifunc,
                     conf_finish_func *ffunc)
 {
     if (module_add(NULL, name, ifunc, ffunc))
         return 1;
     else
         return 0;
 }

 void ossl_config_modules_free(void)
 {
     CONF_modules_finish();
     CONF_modules_unload(1);
 }

 /* Utility functions */

 const char *CONF_imodule_get_name(const CONF_IMODULE *md)
 {
     return md->name;
 }

 const char *CONF_imodule_get_value(const CONF_IMODULE *md)
 {
     return md->value;
 }

 void *CONF_imodule_get_usr_data(const CONF_IMODULE *md)
 {
     return md->usr_data;
 }

 void CONF_imodule_set_usr_data(CONF_IMODULE *md, void *usr_data)
 {
     md->usr_data = usr_data;
 }

 CONF_MODULE *CONF_imodule_get_module(const CONF_IMODULE *md)
 {
     return md->pmod;
 }

 unsigned long CONF_imodule_get_flags(const CONF_IMODULE *md)
 {
     return md->flags;
 }

 void CONF_imodule_set_flags(CONF_IMODULE *md, unsigned long flags)
 {
     md->flags = flags;
 }

 void *CONF_module_get_usr_data(CONF_MODULE *pmod)
 {
     return pmod->usr_data;
 }

 void CONF_module_set_usr_data(CONF_MODULE *pmod, void *usr_data)
 {
     pmod->usr_data = usr_data;
 }

 /* Return default config file name */
 char *CONF_get1_default_config_file(void)
 {
     const char *t;
     char *file, *sep = "";
     size_t size;

     if ((file = ossl_safe_getenv("OPENSSL_CONF")) != NULL)
         return OPENSSL_strdup(file);

     t = X509_get_default_cert_area();
 #ifndef OPENSSL_SYS_VMS
     sep = "/";
 #endif
     size = strlen(t) + strlen(sep) + strlen(OPENSSL_CONF) + 1;
     file = OPENSSL_malloc(size);

     if (file == NULL)
         return NULL;
     BIO_snprintf(file, size, "%s%s%s", t, sep, OPENSSL_CONF);

     return file;
 }

 /*
  * This function takes a list separated by 'sep' and calls the callback
  * function giving the start and length of each member optionally stripping
  * leading and trailing whitespace. This can be used to parse comma separated
  * lists for example.
  */

 int CONF_parse_list(const char *list_, int sep, int nospc,
                     int (*list_cb) (const char *elem, int len, void *usr),
                     void *arg)
 {
     int ret;
     const char *lstart, *tmpend, *p;

     if (list_ == NULL) {
         ERR_raise(ERR_LIB_CONF, CONF_R_LIST_CANNOT_BE_NULL);
         return 0;
     }

     lstart = list_;
     for (;;) {
         if (nospc) {
             while (*lstart && isspace((unsigned char)*lstart))
                 lstart++;
         }
         p = strchr(lstart, sep);
         if (p == lstart || *lstart == '\0')
             ret = list_cb(NULL, 0, arg);
         else {
             if (p)
                 tmpend = p - 1;
             else
                 tmpend = lstart + strlen(lstart) - 1;
             if (nospc) {
                 while (isspace((unsigned char)*tmpend))
                     tmpend--;
             }
             ret = list_cb(lstart, tmpend - lstart + 1, arg);
         }
         if (ret <= 0)
             return ret;
         if (p == NULL)
             return 1;
         lstart = p + 1;
     }
 }
	/*
	* Copyright 2002-2021 The OpenSSL Project Authors. All Rights Reserved.
	*
	* Licensed under the Apache License 2.0 (the "License"). You may not use
	* this file except in compliance with the License. You can obtain a copy
	* in the file LICENSE in the source distribution or at
	* https://www.openssl.org/source/license.html
	*/

	/* We need to use some engine deprecated APIs */
	#define OPENSSL_SUPPRESS_DEPRECATED

	#include "internal/cryptlib.h"
	#include <stdio.h>
	#include <ctype.h>
	#include <openssl/crypto.h>
	#include "internal/conf.h"
	#include <openssl/conf_api.h>
	#include "internal/dso.h"
	#include "internal/thread_once.h"
	#include <openssl/x509.h>
	#include <openssl/trace.h>
	#include <openssl/engine.h>
	#include "conf_local.h"

	DEFINE_STACK_OF(CONF_MODULE)
	DEFINE_STACK_OF(CONF_IMODULE)

	#define DSO_mod_init_name "OPENSSL_init"
	#define DSO_mod_finish_name "OPENSSL_finish"

	/*
	* This structure contains a data about supported modules. entries in this
	* table correspond to either dynamic or static modules.
	*/

	struct conf_module_st {
	/* DSO of this module or NULL if static */
	DSO *dso;
	/* Name of the module */
	char *name;
	/* Init function */
	conf_init_func *init;
	/* Finish function */
	conf_finish_func *finish;
	/* Number of successfully initialized modules */
	int links;
	void *usr_data;
	};

	/*
	* This structure contains information about modules that have been
	* successfully initialized. There may be more than one entry for a given
	* module.
	*/

	struct conf_imodule_st {
	CONF_MODULE *pmod;
	char *name;
	char *value;
	unsigned long flags;
	void *usr_data;
	};

	static STACK_OF(CONF_MODULE) *supported_modules = NULL;
	static STACK_OF(CONF_IMODULE) *initialized_modules = NULL;

	static CRYPTO_ONCE load_builtin_modules = CRYPTO_ONCE_STATIC_INIT;

	static void module_free(CONF_MODULE *md);
	static void module_finish(CONF_IMODULE *imod);
	static int module_run(const CONF cnf, const char name, const char *value,
	unsigned long flags);
	static CONF_MODULE module_add(DSO dso, const char *name,
	conf_init_func *ifunc,
	conf_finish_func *ffunc);
	static CONF_MODULE module_find(const char name);
	static int module_init(CONF_MODULE pmod, const char name, const char *value,
	const CONF *cnf);
	static CONF_MODULE module_load_dso(const CONF cnf, const char *name,
	const char *value);

	static int conf_diagnostics(const CONF *cnf)
	{
	return _CONF_get_number(cnf, NULL, "config_diagnostics") != 0;
	}

	/* Main function: load modules from a CONF structure */

	int CONF_modules_load(const CONF cnf, const char appname,
	unsigned long flags)
	{
	STACK_OF(CONF_VALUE) *values;
	CONF_VALUE *vl;
	char *vsection = NULL;
	int ret, i;

	if (!cnf)
	return 1;

	if (conf_diagnostics(cnf))
	flags &= ~(CONF_MFLAGS_IGNORE_ERRORS
	\| CONF_MFLAGS_IGNORE_RETURN_CODES
	\| CONF_MFLAGS_SILENT
	\| CONF_MFLAGS_IGNORE_MISSING_FILE);

	ERR_set_mark();
	if (appname)
	vsection = NCONF_get_string(cnf, NULL, appname);

	if (!appname \|\| (!vsection && (flags & CONF_MFLAGS_DEFAULT_SECTION)))
	vsection = NCONF_get_string(cnf, NULL, "openssl_conf");

	if (!vsection) {
	ERR_pop_to_mark();
	return 1;
	}

	OSSL_TRACE1(CONF, "Configuration in section %s\n", vsection);
	values = NCONF_get_section(cnf, vsection);

	if (values == NULL) {
	if (!(flags & CONF_MFLAGS_SILENT)) {
	ERR_clear_last_mark();
	ERR_raise_data(ERR_LIB_CONF,
	CONF_R_OPENSSL_CONF_REFERENCES_MISSING_SECTION,
	"openssl_conf=%s", vsection);
	} else {
	ERR_pop_to_mark();
	}
	return 0;
	}
	ERR_pop_to_mark();

	for (i = 0; i < sk_CONF_VALUE_num(values); i++) {
	vl = sk_CONF_VALUE_value(values, i);
	ERR_set_mark();
	ret = module_run(cnf, vl->name, vl->value, flags);
	OSSL_TRACE3(CONF, "Running module %s (%s) returned %d\n",
	vl->name, vl->value, ret);
	if (ret <= 0)
	if (!(flags & CONF_MFLAGS_IGNORE_ERRORS)) {
	ERR_clear_last_mark();
	return ret;
	}
	ERR_pop_to_mark();
	}

	return 1;

	}

	int CONF_modules_load_file_ex(OSSL_LIB_CTX libctx, const char filename,
	const char *appname, unsigned long flags)
	{
	char *file = NULL;
	CONF *conf = NULL;
	int ret = 0, diagnostics = 0;

	if (filename == NULL) {
	file = CONF_get1_default_config_file();
	if (file == NULL)
	goto err;
	} else {
	file = (char *)filename;
	}

	ERR_set_mark();
	conf = NCONF_new_ex(libctx, NULL);
	if (conf == NULL)
	goto err;

	if (NCONF_load(conf, file, NULL) <= 0) {
	if ((flags & CONF_MFLAGS_IGNORE_MISSING_FILE) &&
	(ERR_GET_REASON(ERR_peek_last_error()) == CONF_R_NO_SUCH_FILE)) {
	ret = 1;
	}
	goto err;
	}

	ret = CONF_modules_load(conf, appname, flags);
	diagnostics = conf_diagnostics(conf);

	err:
	if (filename == NULL)
	OPENSSL_free(file);
	NCONF_free(conf);

	if ((flags & CONF_MFLAGS_IGNORE_RETURN_CODES) != 0 && !diagnostics)
	ret = 1;

	if (ret > 0)
	ERR_pop_to_mark();
	else
	ERR_clear_last_mark();

	return ret;
	}

	int CONF_modules_load_file(const char *filename,
	const char *appname, unsigned long flags)
	{
	return CONF_modules_load_file_ex(NULL, filename, appname, flags);
	}

	DEFINE_RUN_ONCE_STATIC(do_load_builtin_modules)
	{
	OPENSSL_load_builtin_modules();
	#ifndef OPENSSL_NO_ENGINE
	/* Need to load ENGINEs */
	ENGINE_load_builtin_engines();
	#endif
	return 1;
	}

	static int module_run(const CONF cnf, const char name, const char *value,
	unsigned long flags)
	{
	CONF_MODULE *md;
	int ret;

	if (!RUN_ONCE(&load_builtin_modules, do_load_builtin_modules))
	return -1;

	md = module_find(name);

	/* Module not found: try to load DSO */
	if (!md && !(flags & CONF_MFLAGS_NO_DSO))
	md = module_load_dso(cnf, name, value);

	if (!md) {
	if (!(flags & CONF_MFLAGS_SILENT)) {
	ERR_raise_data(ERR_LIB_CONF, CONF_R_UNKNOWN_MODULE_NAME,
	"module=%s", name);
	}
	return -1;
	}

	ret = module_init(md, name, value, cnf);

	if (ret <= 0) {
	if (!(flags & CONF_MFLAGS_SILENT))
	ERR_raise_data(ERR_LIB_CONF, CONF_R_MODULE_INITIALIZATION_ERROR,
	"module=%s, value=%s retcode=%-8d",
	name, value, ret);
	}

	return ret;
	}

	/* Load a module from a DSO */
	static CONF_MODULE module_load_dso(const CONF cnf,
	const char name, const char value)
	{
	DSO *dso = NULL;
	conf_init_func *ifunc;
	conf_finish_func *ffunc;
	const char *path = NULL;
	int errcode = 0;
	CONF_MODULE *md;

	/* Look for alternative path in module section */
	path = _CONF_get_string(cnf, value, "path");
	if (path == NULL) {
	path = name;
	}
	dso = DSO_load(NULL, path, NULL, 0);
	if (dso == NULL) {
	errcode = CONF_R_ERROR_LOADING_DSO;
	goto err;
	}
	ifunc = (conf_init_func *)DSO_bind_func(dso, DSO_mod_init_name);
	if (ifunc == NULL) {
	errcode = CONF_R_MISSING_INIT_FUNCTION;
	goto err;
	}
	ffunc = (conf_finish_func *)DSO_bind_func(dso, DSO_mod_finish_name);
	/* All OK, add module */
	md = module_add(dso, name, ifunc, ffunc);

	if (md == NULL)
	goto err;

	return md;

	err:
	DSO_free(dso);
	ERR_raise_data(ERR_LIB_CONF, errcode, "module=%s, path=%s", name, path);
	return NULL;
	}

	/* add module to list */
	static CONF_MODULE module_add(DSO dso, const char *name,
	conf_init_func ifunc, conf_finish_func ffunc)
	{
	CONF_MODULE *tmod = NULL;
	if (supported_modules == NULL)
	supported_modules = sk_CONF_MODULE_new_null();
	if (supported_modules == NULL)
	return NULL;
	if ((tmod = OPENSSL_zalloc(sizeof(*tmod))) == NULL) {
	ERR_raise(ERR_LIB_CONF, ERR_R_MALLOC_FAILURE);
	return NULL;
	}

	tmod->dso = dso;
	tmod->name = OPENSSL_strdup(name);
	tmod->init = ifunc;
	tmod->finish = ffunc;
	if (tmod->name == NULL) {
	OPENSSL_free(tmod);
	return NULL;
	}

	if (!sk_CONF_MODULE_push(supported_modules, tmod)) {
	OPENSSL_free(tmod->name);
	OPENSSL_free(tmod);
	return NULL;
	}

	return tmod;
	}

	/*
	* Find a module from the list. We allow module names of the form
	* modname.XXXX to just search for modname to allow the same module to be
	* initialized more than once.
	*/

	static CONF_MODULE module_find(const char name)
	{
	CONF_MODULE *tmod;
	int i, nchar;
	char *p;
	p = strrchr(name, '.');

	if (p)
	nchar = p - name;
	else
	nchar = strlen(name);

	for (i = 0; i < sk_CONF_MODULE_num(supported_modules); i++) {
	tmod = sk_CONF_MODULE_value(supported_modules, i);
	if (strncmp(tmod->name, name, nchar) == 0)
	return tmod;
	}

	return NULL;

	}

	/* initialize a module */
	static int module_init(CONF_MODULE pmod, const char name, const char *value,
	const CONF *cnf)
	{
	int ret = 1;
	int init_called = 0;
	CONF_IMODULE *imod = NULL;

	/* Otherwise add initialized module to list */
	imod = OPENSSL_malloc(sizeof(*imod));
	if (imod == NULL)
	goto err;

	imod->pmod = pmod;
	imod->name = OPENSSL_strdup(name);
	imod->value = OPENSSL_strdup(value);
	imod->usr_data = NULL;

	if (!imod->name \|\| !imod->value)
	goto memerr;

	/* Try to initialize module */
	if (pmod->init) {
	ret = pmod->init(imod, cnf);
	init_called = 1;
	/* Error occurred, exit */
	if (ret <= 0)
	goto err;
	}

	if (initialized_modules == NULL) {
	initialized_modules = sk_CONF_IMODULE_new_null();
	if (!initialized_modules) {
	ERR_raise(ERR_LIB_CONF, ERR_R_MALLOC_FAILURE);
	goto err;
	}
	}

	if (!sk_CONF_IMODULE_push(initialized_modules, imod)) {
	ERR_raise(ERR_LIB_CONF, ERR_R_MALLOC_FAILURE);
	goto err;
	}

	pmod->links++;

	return ret;

	err:

	/* We've started the module so we'd better finish it */
	if (pmod->finish && init_called)
	pmod->finish(imod);

	memerr:
	if (imod) {
	OPENSSL_free(imod->name);
	OPENSSL_free(imod->value);
	OPENSSL_free(imod);
	}

	return -1;

	}

	/*
	* Unload any dynamic modules that have a link count of zero: i.e. have no
	* active initialized modules. If 'all' is set then all modules are unloaded
	* including static ones.
	*/

	void CONF_modules_unload(int all)
	{
	int i;
	CONF_MODULE *md;
	CONF_modules_finish();
	/* unload modules in reverse order */
	for (i = sk_CONF_MODULE_num(supported_modules) - 1; i >= 0; i--) {
	md = sk_CONF_MODULE_value(supported_modules, i);
	/* If static or in use and 'all' not set ignore it */
	if (((md->links > 0) \|\| !md->dso) && !all)
	continue;
	/* Since we're working in reverse this is OK */
	(void)sk_CONF_MODULE_delete(supported_modules, i);
	module_free(md);
	}
	if (sk_CONF_MODULE_num(supported_modules) == 0) {
	sk_CONF_MODULE_free(supported_modules);
	supported_modules = NULL;
	}
	}

	/* unload a single module */
	static void module_free(CONF_MODULE *md)
	{
	DSO_free(md->dso);
	OPENSSL_free(md->name);
	OPENSSL_free(md);
	}

	/* finish and free up all modules instances */

	void CONF_modules_finish(void)
	{
	CONF_IMODULE *imod;
	while (sk_CONF_IMODULE_num(initialized_modules) > 0) {
	imod = sk_CONF_IMODULE_pop(initialized_modules);
	module_finish(imod);
	}
	sk_CONF_IMODULE_free(initialized_modules);
	initialized_modules = NULL;
	}

	/* finish a module instance */

	static void module_finish(CONF_IMODULE *imod)
	{
	if (!imod)
	return;
	if (imod->pmod->finish)
	imod->pmod->finish(imod);
	imod->pmod->links--;
	OPENSSL_free(imod->name);
	OPENSSL_free(imod->value);
	OPENSSL_free(imod);
	}

	/* Add a static module to OpenSSL */

	int CONF_module_add(const char name, conf_init_func ifunc,
	conf_finish_func *ffunc)
	{
	if (module_add(NULL, name, ifunc, ffunc))
	return 1;
	else
	return 0;
	}

	void ossl_config_modules_free(void)
	{
	CONF_modules_finish();
	CONF_modules_unload(1);
	}

	/* Utility functions */

	const char CONF_imodule_get_name(const CONF_IMODULE md)
	{
	return md->name;
	}

	const char CONF_imodule_get_value(const CONF_IMODULE md)
	{
	return md->value;
	}

	void CONF_imodule_get_usr_data(const CONF_IMODULE md)
	{
	return md->usr_data;
	}

	void CONF_imodule_set_usr_data(CONF_IMODULE md, void usr_data)
	{
	md->usr_data = usr_data;
	}

	CONF_MODULE CONF_imodule_get_module(const CONF_IMODULE md)
	{
	return md->pmod;
	}

	unsigned long CONF_imodule_get_flags(const CONF_IMODULE *md)
	{
	return md->flags;
	}

	void CONF_imodule_set_flags(CONF_IMODULE *md, unsigned long flags)
	{
	md->flags = flags;
	}

	void CONF_module_get_usr_data(CONF_MODULE pmod)
	{
	return pmod->usr_data;
	}

	void CONF_module_set_usr_data(CONF_MODULE pmod, void usr_data)
	{
	pmod->usr_data = usr_data;
	}

	/* Return default config file name */
	char *CONF_get1_default_config_file(void)
	{
	const char *t;
	char file, sep = "";
	size_t size;

	if ((file = ossl_safe_getenv("OPENSSL_CONF")) != NULL)
	return OPENSSL_strdup(file);

	t = X509_get_default_cert_area();
	#ifndef OPENSSL_SYS_VMS
	sep = "/";
	#endif
	size = strlen(t) + strlen(sep) + strlen(OPENSSL_CONF) + 1;
	file = OPENSSL_malloc(size);

	if (file == NULL)
	return NULL;
	BIO_snprintf(file, size, "%s%s%s", t, sep, OPENSSL_CONF);

	return file;
	}

	/*
	* This function takes a list separated by 'sep' and calls the callback
	* function giving the start and length of each member optionally stripping
	* leading and trailing whitespace. This can be used to parse comma separated
	* lists for example.
	*/

	int CONF_parse_list(const char *list_, int sep, int nospc,
	int (list_cb) (const char elem, int len, void *usr),
	void *arg)
	{
	int ret;
	const char lstart, tmpend, *p;

	if (list_ == NULL) {
	ERR_raise(ERR_LIB_CONF, CONF_R_LIST_CANNOT_BE_NULL);
	return 0;
	}

	lstart = list_;
	for (;;) {
	if (nospc) {
	while (lstart && isspace((unsigned char)lstart))
	lstart++;
	}
	p = strchr(lstart, sep);
	if (p == lstart \|\| *lstart == '\0')
	ret = list_cb(NULL, 0, arg);
	else {
	if (p)
	tmpend = p - 1;
	else
	tmpend = lstart + strlen(lstart) - 1;
	if (nospc) {
	while (isspace((unsigned char)*tmpend))
	tmpend--;
	}
	ret = list_cb(lstart, tmpend - lstart + 1, arg);
	}
	if (ret <= 0)
	return ret;
	if (p == NULL)
	return 1;
	lstart = p + 1;
	}
	}