/*

 * Copyright 1995-2025 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

 */

#include <stdio.h>

#include <openssl/opensslv.h>

#include "internal/thread_once.h"

#include "internal/cryptlib.h"

#include "internal/e_os.h"

#if defined(_WIN32) && defined(OSSL_WINCTX)

#define TOSTR(x) #x

#define MAKESTR(x) TOSTR(x)

#define NOQUOTE(x) x

#if defined(OSSL_WINCTX)

#define REGISTRY_KEY "SOFTWARE\\WOW6432Node\\OpenSSL" \

                     "-" MAKESTR(OPENSSL_VERSION_MAJOR) "." MAKESTR(OPENSSL_VERSION_MINOR) "-" MAKESTR(OSSL_WINCTX)

#endif

/**

 * @brief The directory where OpenSSL is installed.

 */

static char openssldir[MAX_PATH + 1];

/**

 * @brief The pointer to the openssldir buffer

 */

static char *openssldirptr = NULL;

/**

 * @brief The directory where OpenSSL modules are located.

 */

static char modulesdir[MAX_PATH + 1];

/**

 * @brief The pointer to the modulesdir buffer

 */

static char *modulesdirptr = NULL;

/**

 * @brief Get the list of Windows registry directories.

 *

 * This function retrieves a list of Windows registry directories.

 *

 * @return A pointer to a char array containing the registry directories.

 */

static char *get_windows_regdirs(char *dst, DWORD dstsizebytes, LPCWSTR valuename)

{

    char *retval = NULL;

#ifdef REGISTRY_KEY

    DWORD keysizebytes;

    DWORD ktype;

    HKEY hkey;

    LSTATUS ret;

    DWORD index = 0;

    LPCWSTR tempstr = NULL;

    ret = RegOpenKeyEx(HKEY_LOCAL_MACHINE,

        TEXT(REGISTRY_KEY), KEY_WOW64_32KEY,

        KEY_QUERY_VALUE, &hkey);

    if (ret != ERROR_SUCCESS)

        goto out;

    /* Always use wide call so we can avoid extra encoding conversions on the output */

    ret = RegQueryValueExW(hkey, valuename, NULL, &ktype, NULL,

        &keysizebytes);

    if (ret != ERROR_SUCCESS)

        goto out;

    if (ktype != REG_EXPAND_SZ && ktype != REG_SZ)

        goto out;

    if (keysizebytes > MAX_PATH * sizeof(WCHAR))

        goto out;

    /*

     * RegQueryValueExW does not guarantee the buffer is null terminated,

     * so we make space for one in the allocation

     */

    tempstr = OPENSSL_zalloc(keysizebytes + sizeof(WCHAR));

    if (tempstr == NULL)

        goto out;

    if (RegQueryValueExW(hkey, valuename,

            NULL, &ktype, (LPBYTE)tempstr, &keysizebytes)

        != ERROR_SUCCESS)

        goto out;

    if (!WideCharToMultiByte(CP_UTF8, 0, tempstr, -1, dst, dstsizebytes,

            NULL, NULL))

        goto out;

    retval = dst;

out:

    OPENSSL_free(tempstr);

    RegCloseKey(hkey);

#endif /* REGISTRY_KEY */

    return retval;

}

static CRYPTO_ONCE defaults_setup_init = CRYPTO_ONCE_STATIC_INIT;

/**

 * @brief Function to setup default values to run once.

 * Only used in Windows environments.  Does run time initialization

 * of openssldir/modulesdir/enginesdir from the registry

 */

DEFINE_RUN_ONCE_STATIC(do_defaults_setup)

{

    get_windows_regdirs(openssldir, sizeof(openssldir), L"OPENSSLDIR");

    get_windows_regdirs(modulesdir, sizeof(modulesdir), L"MODULESDIR");

    /*

     * Set our pointers only if the directories are fetched properly

     */

    if (strlen(openssldir) > 0)

        openssldirptr = openssldir;

    if (strlen(modulesdir) > 0)

        modulesdirptr = modulesdir;

    return 1;

}

#endif /* defined(_WIN32) && defined(OSSL_WINCTX) */

/**

 * @brief Get the directory where OpenSSL is installed.

 *

 * @return A pointer to a string containing the OpenSSL directory path.

 */

const char *ossl_get_openssldir(void)

{

#if defined(_WIN32) && defined(OSSL_WINCTX)

    if (!RUN_ONCE(&defaults_setup_init, do_defaults_setup))

        return NULL;

    return (const char *)openssldirptr;

#else

    return OPENSSLDIR;

#endif

}

/**

 * @brief Get the directory where OpenSSL modules are located.

 *

 * @return A pointer to a string containing the modules directory path.

 */

const char *ossl_get_modulesdir(void)

{

#if defined(_WIN32) && defined(OSSL_WINCTX)

    if (!RUN_ONCE(&defaults_setup_init, do_defaults_setup))

        return NULL;

    return (const char *)modulesdirptr;

#else

    return MODULESDIR;

#endif

}

/**

 * @brief Get the build time defined windows installer context

 *

 * @return A char pointer to a string representing the windows install context

 */

const char *ossl_get_wininstallcontext(void)

{

#if defined(_WIN32) && defined(OSSL_WINCTX)

    return MAKESTR(OSSL_WINCTX);

#else

    return "Undefined";

#endif

}