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Modified WP setup-config.php with install-key protection. https://smitka.me/2022/07/01/wordpress-installer-attack-race/
<?php
/**
* Retrieves and creates the wp-config.php file.
*
* The permissions for the base directory must allow for writing files in order
* for the wp-config.php to be created using this page.
*
* @package WordPress
* @subpackage Administration
*/
/**
* Lynt WP Installer Security PoC2
* https://screencast-o-matic.com/watch/c3ifl3V0TNB
**/
/**
* We are installing.
*/
define( 'WP_INSTALLING', true );
/**
* We are blissfully unaware of anything.
*/
define( 'WP_SETUP_CONFIG', true );
/**
* Disable error reporting
*
* Set this to error_reporting( -1 ) for debugging
*/
error_reporting( 0 );
if ( ! defined( 'ABSPATH' ) ) {
define( 'ABSPATH', dirname( __DIR__ ) . '/' );
}
require ABSPATH . 'wp-settings.php';
/** Load WordPress Administration Upgrade API */
require_once ABSPATH . 'wp-admin/includes/upgrade.php';
/** Load WordPress Translation Installation API */
require_once ABSPATH . 'wp-admin/includes/translation-install.php';
nocache_headers();
// Functions to check allowed DB hosts
// Get regexp to verify dbhost
function get_dbhost_allowed_regexp() {
// default settings - allow localhost only
// possible enhacement: translate host to IP and allow local subnets
$allowed_dbhost_regexp = '^(?:localhost|127\.0\.0\.1)$';
// if there is enviroment varianle defined use it
// the webhoster can modify default settings
if ( getenv( 'WP_ALLOWED_DBHOSTS' ) ) {
$allowed_dbhost_regexp = getenv( 'WP_ALLOWED_DBHOSTS' );
}
return $allowed_dbhost_regexp;
}
// Check dbhost
function is_dbhost_allowed( $dbhost ) {
$allowed_dbhost_regexp = get_dbhost_allowed_regexp();
if ( preg_match( '#' . $allowed_dbhost_regexp . '#i', $dbhost)) {
return true;
}
return false;
}
// END allowed DB hosts check
// Support wp-config-sample.php one level up, for the develop repo.
if ( file_exists( ABSPATH . 'wp-config-sample.php' ) ) {
$config_file = file( ABSPATH . 'wp-config-sample.php' );
} elseif ( file_exists( dirname( ABSPATH ) . '/wp-config-sample.php' ) ) {
$config_file = file( dirname( ABSPATH ) . '/wp-config-sample.php' );
} else {
wp_die(
sprintf(
/* translators: %s: wp-config-sample.php */
__( 'Sorry, I need a %s file to work from. Please re-upload this file to your WordPress installation.' ),
'<code>wp-config-sample.php</code>'
)
);
}
// Check if wp-config.php has been created.
if ( file_exists( ABSPATH . 'wp-config.php' ) ) {
wp_die(
'<p>' . sprintf(
/* translators: 1: wp-config.php, 2: install.php */
__( 'The file %1$s already exists. If you need to reset any of the configuration items in this file, please delete it first. You may try <a href="%2$s">installing now</a>.' ),
'<code>wp-config.php</code>',
'install.php'
) . '</p>',
409
);
}
// Check if wp-config.php exists above the root directory but is not part of another installation.
if ( @file_exists( ABSPATH . '../wp-config.php' ) && ! @file_exists( ABSPATH . '../wp-settings.php' ) ) {
wp_die(
'<p>' . sprintf(
/* translators: 1: wp-config.php, 2: install.php */
__( 'The file %1$s already exists one level above your WordPress installation. If you need to reset any of the configuration items in this file, please delete it first. You may try <a href="%2$s">installing now</a>.' ),
'<code>wp-config.php</code>',
'install.php'
) . '</p>',
409
);
}
$step = isset( $_GET['step'] ) ? (int) $_GET['step'] : -1;
/**
* Display setup wp-config.php file header.
*
* @ignore
* @since 2.3.0
*
* @param string|string[] $body_classes Class attribute values for the body tag.
*/
function setup_config_display_header( $body_classes = array() ) {
$body_classes = (array) $body_classes;
$body_classes[] = 'wp-core-ui';
$dir_attr = '';
if ( is_rtl() ) {
$body_classes[] = 'rtl';
$dir_attr = ' dir="rtl"';
}
header( 'Content-Type: text/html; charset=utf-8' );
?>
<!DOCTYPE html>
<html<?php echo $dir_attr; ?>>
<head>
<meta name="viewport" content="width=device-width" />
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta name="robots" content="noindex,nofollow" />
<title><?php _e( 'WordPress &rsaquo; Setup Configuration File' ); ?></title>
<?php wp_admin_css( 'install', true ); ?>
</head>
<body class="<?php echo implode( ' ', $body_classes ); ?>">
<p id="logo"><?php _e( 'WordPress' ); ?></p>
<?php
} // End function setup_config_display_header();
$language = '';
if ( ! empty( $_REQUEST['language'] ) ) {
$language = preg_replace( '/[^a-zA-Z0-9_]/', '', $_REQUEST['language'] );
} elseif ( isset( $GLOBALS['wp_local_package'] ) ) {
$language = $GLOBALS['wp_local_package'];
}
switch ( $step ) {
case -1:
if ( wp_can_install_language_pack() && empty( $language ) ) {
$languages = wp_get_available_translations();
if ( $languages ) {
setup_config_display_header( 'language-chooser' );
echo '<h1 class="screen-reader-text">Select a default language</h1>';
echo '<form id="setup" method="post" action="?step=0">';
wp_install_language_form( $languages );
echo '</form>';
break;
}
}
// Deliberately fall through if we can't reach the translations API.
case 0:
if ( ! empty( $language ) ) {
$loaded_language = wp_download_language_pack( $language );
if ( $loaded_language ) {
load_default_textdomain( $loaded_language );
$GLOBALS['wp_locale'] = new WP_Locale();
}
}
setup_config_display_header();
$step_1 = 'setup-config.php?step=1';
if ( isset( $_REQUEST['noapi'] ) ) {
$step_1 .= '&amp;noapi';
}
if ( ! empty( $loaded_language ) ) {
$step_1 .= '&amp;language=' . $loaded_language;
}
?>
<h1 class="screen-reader-text"><?php _e( 'Before getting started' ); ?></h1>
<p><?php _e( 'Welcome to WordPress. Before getting started, you will need to know the following items.' ); ?></p>
<ol>
<li><?php _e( 'Database name' ); ?></li>
<li><?php _e( 'Database username' ); ?></li>
<li><?php _e( 'Database password' ); ?></li>
<li><?php _e( 'Database host' ); ?></li>
<li><?php _e( 'Table prefix (if you want to run more than one WordPress in a single database)' ); ?></li>
</ol>
<p>
<?php
printf(
/* translators: %s: wp-config.php */
__( 'This information is being used to create a %s file.' ),
'<code>wp-config.php</code>'
);
?>
<strong>
<?php
printf(
/* translators: 1: wp-config-sample.php, 2: wp-config.php */
__( 'If for any reason this automatic file creation does not work, do not worry. All this does is fill in the database information to a configuration file. You may also simply open %1$s in a text editor, fill in your information, and save it as %2$s.' ),
'<code>wp-config-sample.php</code>',
'<code>wp-config.php</code>'
);
?>
</strong>
<?php
printf(
/* translators: 1: Documentation URL, 2: wp-config.php */
__( 'Need more help? <a href="%1$s">Read the support article on %2$s</a>.' ),
__( 'https://wordpress.org/support/article/editing-wp-config-php/' ),
'<code>wp-config.php</code>'
);
?>
</p>
<p><?php _e( 'In all likelihood, these items were supplied to you by your web host. If you do not have this information, then you will need to contact them before you can continue. If you are ready&hellip;' ); ?></p>
<p class="step"><a href="<?php echo $step_1; ?>" class="button button-large"><?php _e( 'Let&#8217;s go!' ); ?></a></p>
<?php
break;
case 1:
load_default_textdomain( $language );
$GLOBALS['wp_locale'] = new WP_Locale();
setup_config_display_header();
// Generate install key and save it in install-key.php
$chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
$max = strlen( $chars ) - 1;
$install_key = '';
for ( $i = 0; $i < 12; $i++ ) {
$install_key .= substr( $chars, random_int( 0, $max ), 1 );
}
$install_key_file_msg = __( 'Check the content of this file via S/FTP.' );
file_put_contents( ABSPATH . '/install-key.php', "<?php\n/**\n\nYour install key is:\n{$install_key}\n\n**/\n\ndefine('INSTALL_KEY', '{$install_key}');\n\nif ( !defined( 'ABSPATH' )) echo '$install_key_file_msg';");
// Install key end
$autofocus = wp_is_mobile() ? '' : ' autofocus';
?>
<h1 class="screen-reader-text"><?php _e( 'Set up your database connection' ); ?></h1>
<form method="post" action="setup-config.php?step=2">
<p><?php _e( 'Below you should enter your database connection details. If you are not sure about these, contact your host.' ); ?></p>
<table class="form-table" role="presentation">
<tr>
<th scope="row"><label for="dbname"><?php _e( 'Database Name' ); ?></label></th>
<td><input name="dbname" id="dbname" type="text" aria-describedby="dbname-desc" size="25" value="wordpress"<?php echo $autofocus; ?>/></td>
<td id="dbname-desc"><?php _e( 'The name of the database you want to use with WordPress.' ); ?></td>
</tr>
<tr>
<th scope="row"><label for="uname"><?php _e( 'Username' ); ?></label></th>
<td><input name="uname" id="uname" type="text" aria-describedby="uname-desc" size="25" value="<?php echo htmlspecialchars( _x( 'username', 'example username' ), ENT_QUOTES ); ?>" /></td>
<td id="uname-desc"><?php _e( 'Your database username.' ); ?></td>
</tr>
<tr>
<th scope="row"><label for="pwd"><?php _e( 'Password' ); ?></label></th>
<td><input name="pwd" id="pwd" type="text" aria-describedby="pwd-desc" size="25" value="<?php echo htmlspecialchars( _x( 'password', 'example password' ), ENT_QUOTES ); ?>" autocomplete="off" /></td>
<td id="pwd-desc"><?php _e( 'Your database password.' ); ?></td>
</tr>
<tr>
<th scope="row"><label for="dbhost"><?php _e( 'Database Host' ); ?></label></th>
<td><input name="dbhost" id="dbhost" type="text" aria-describedby="dbhost-desc" size="25" value="localhost" /></td>
<td id="dbhost-desc">
<?php
/* translators: %s: localhost */
printf( __( 'You should be able to get this info from your web host, if %s does not work.' ), '<code>localhost</code>' );
?>
</td>
</tr>
<tr>
<th scope="row"><label for="prefix"><?php _e( 'Table Prefix' ); ?></label></th>
<td><input name="prefix" id="prefix" type="text" aria-describedby="prefix-desc" value="wp_" size="25" /></td>
<td id="prefix-desc"><?php _e( 'If you want to run multiple WordPress installations in a single database, change this.' ); ?></td>
</tr>
<tr id="install_key_row" style="display:none">
<th scope="row"><label for="install_key"><?php _e( 'Install key' ); ?></label></th>
<td><input name="install_key" id="install_key" type="text" aria-describedby="install_key-desc" value="" size="25" /></td>
<td id="install_key-desc"><?php _e( 'Additional verification for is needed for your Database Host. Check the install-key.php file.' ); ?></td>
</tr>
<script>
document.getElementById('dbhost').addEventListener('change', show_install_key);
window.addEventListener('load', show_install_key);
function show_install_key(){
var allowed_dbhost_regexp = /<?php echo get_dbhost_allowed_regexp(); ?>/i;
if ( !allowed_dbhost_regexp.test(document.getElementById('dbhost').value) ) {
document.getElementById('install_key_row').style.display = 'table-row';
}
else {
document.getElementById('install_key_row').style.display = 'none';
}
}
</script>
</table>
<?php
if ( isset( $_GET['noapi'] ) ) {
?>
<input name="noapi" type="hidden" value="1" /><?php } ?>
<input type="hidden" name="language" value="<?php echo esc_attr( $language ); ?>" />
<p class="step"><input name="submit" type="submit" value="<?php echo htmlspecialchars( __( 'Submit' ), ENT_QUOTES ); ?>" class="button button-large" /></p>
</form>
<?php
break;
case 2:
load_default_textdomain( $language );
$GLOBALS['wp_locale'] = new WP_Locale();
$dbname = trim( wp_unslash( $_POST['dbname'] ) );
$uname = trim( wp_unslash( $_POST['uname'] ) );
$pwd = trim( wp_unslash( $_POST['pwd'] ) );
$dbhost = trim( wp_unslash( $_POST['dbhost'] ) );
$prefix = trim( wp_unslash( $_POST['prefix'] ) );
$step_1 = 'setup-config.php?step=1';
$install = 'install.php';
if ( isset( $_REQUEST['noapi'] ) ) {
$step_1 .= '&amp;noapi';
}
if ( ! empty( $language ) ) {
$step_1 .= '&amp;language=' . $language;
$install .= '?language=' . $language;
} else {
$install .= '?language=en_US';
}
$tryagain_link = '</p><p class="step"><a href="' . $step_1 . '" onclick="javascript:history.go(-1);return false;" class="button button-large">' . __( 'Try Again' ) . '</a>';
if ( empty( $prefix ) ) {
wp_die( __( '<strong>Error</strong>: "Table Prefix" must not be empty.' ) . $tryagain_link );
}
if ( !is_dbhost_allowed( $dbhost ) ) {
if ( file_exists( ABSPATH . '/install-key.php' ) ) {
require_once ABSPATH . '/install-key.php';
if ( INSTALL_KEY !== $install_key ) {
wp_die( __( '<strong>Error</strong>: Invalid install key.' ) . $tryagain_link );
}
}
else {
wp_die( __( '<strong>Error</strong>: File install-key.php doesn\'t exists.' ) . $tryagain_link );
}
}
// Validate $prefix: it can only contain letters, numbers and underscores.
if ( preg_match( '|[^a-z0-9_]|i', $prefix ) ) {
wp_die( __( '<strong>Error</strong>: "Table Prefix" can only contain numbers, letters, and underscores.' ) . $tryagain_link );
}
// Test the DB connection.
/**#@+
*
* @ignore
*/
define( 'DB_NAME', $dbname );
define( 'DB_USER', $uname );
define( 'DB_PASSWORD', $pwd );
define( 'DB_HOST', $dbhost );
/**#@-*/
// Re-construct $wpdb with these new values.
unset( $wpdb );
require_wp_db();
/*
* The wpdb constructor bails when WP_SETUP_CONFIG is set, so we must
* fire this manually. We'll fail here if the values are no good.
*/
$wpdb->db_connect();
if ( ! empty( $wpdb->error ) ) {
wp_die( $wpdb->error->get_error_message() . $tryagain_link );
}
$errors = $wpdb->hide_errors();
$wpdb->query( "SELECT $prefix" );
$wpdb->show_errors( $errors );
if ( ! $wpdb->last_error ) {
// MySQL was able to parse the prefix as a value, which we don't want. Bail.
wp_die( __( '<strong>Error</strong>: "Table Prefix" is invalid.' ) );
}
// Generate keys and salts using secure CSPRNG; fallback to API if enabled; further fallback to original wp_generate_password().
try {
$chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@#$%^&*()-_ []{}<>~`+=,.;:/?|';
$max = strlen( $chars ) - 1;
for ( $i = 0; $i < 8; $i++ ) {
$key = '';
for ( $j = 0; $j < 64; $j++ ) {
$key .= substr( $chars, random_int( 0, $max ), 1 );
}
$secret_keys[] = $key;
}
} catch ( Exception $ex ) {
$no_api = isset( $_POST['noapi'] );
if ( ! $no_api ) {
$secret_keys = wp_remote_get( 'https://api.wordpress.org/secret-key/1.1/salt/' );
}
if ( $no_api || is_wp_error( $secret_keys ) ) {
$secret_keys = array();
for ( $i = 0; $i < 8; $i++ ) {
$secret_keys[] = wp_generate_password( 64, true, true );
}
} else {
$secret_keys = explode( "\n", wp_remote_retrieve_body( $secret_keys ) );
foreach ( $secret_keys as $k => $v ) {
$secret_keys[ $k ] = substr( $v, 28, 64 );
}
}
}
$key = 0;
foreach ( $config_file as $line_num => $line ) {
if ( '$table_prefix =' === substr( $line, 0, 15 ) ) {
$config_file[ $line_num ] = '$table_prefix = \'' . addcslashes( $prefix, "\\'" ) . "';\r\n";
continue;
}
if ( ! preg_match( '/^define\(\s*\'([A-Z_]+)\',([ ]+)/', $line, $match ) ) {
continue;
}
$constant = $match[1];
$padding = $match[2];
switch ( $constant ) {
case 'DB_NAME':
case 'DB_USER':
case 'DB_PASSWORD':
case 'DB_HOST':
$config_file[ $line_num ] = "define( '" . $constant . "'," . $padding . "'" . addcslashes( constant( $constant ), "\\'" ) . "' );\r\n";
break;
case 'DB_CHARSET':
if ( 'utf8mb4' === $wpdb->charset || ( ! $wpdb->charset && $wpdb->has_cap( 'utf8mb4' ) ) ) {
$config_file[ $line_num ] = "define( '" . $constant . "'," . $padding . "'utf8mb4' );\r\n";
}
break;
case 'AUTH_KEY':
case 'SECURE_AUTH_KEY':
case 'LOGGED_IN_KEY':
case 'NONCE_KEY':
case 'AUTH_SALT':
case 'SECURE_AUTH_SALT':
case 'LOGGED_IN_SALT':
case 'NONCE_SALT':
$config_file[ $line_num ] = "define( '" . $constant . "'," . $padding . "'" . $secret_keys[ $key++ ] . "' );\r\n";
break;
}
}
unset( $line );
if ( ! is_writable( ABSPATH ) ) :
setup_config_display_header();
?>
<p>
<?php
/* translators: %s: wp-config.php */
printf( __( 'Unable to write to %s file.' ), '<code>wp-config.php</code>' );
?>
</p>
<p>
<?php
/* translators: %s: wp-config.php */
printf( __( 'You can create the %s file manually and paste the following text into it.' ), '<code>wp-config.php</code>' );
$config_text = '';
foreach ( $config_file as $line ) {
$config_text .= htmlentities( $line, ENT_COMPAT, 'UTF-8' );
}
?>
</p>
<textarea id="wp-config" cols="98" rows="15" class="code" readonly="readonly"><?php echo $config_text; ?></textarea>
<p><?php _e( 'After you&#8217;ve done that, click &#8220;Run the installation&#8221;.' ); ?></p>
<p class="step"><a href="<?php echo $install; ?>" class="button button-large"><?php _e( 'Run the installation' ); ?></a></p>
<script>
(function(){
if ( ! /iPad|iPod|iPhone/.test( navigator.userAgent ) ) {
var el = document.getElementById('wp-config');
el.focus();
el.select();
}
})();
</script>
<?php
else :
/*
* If this file doesn't exist, then we are using the wp-config-sample.php
* file one level up, which is for the develop repo.
*/
if ( file_exists( ABSPATH . 'wp-config-sample.php' ) ) {
$path_to_wp_config = ABSPATH . 'wp-config.php';
} else {
$path_to_wp_config = dirname( ABSPATH ) . '/wp-config.php';
}
$error_message = '';
$handle = fopen( $path_to_wp_config, 'w' );
/*
* Why check for the absence of false instead of checking for resource with is_resource()?
* To future-proof the check for when fopen returns object instead of resource, i.e. a known
* change coming in PHP.
*/
if ( false !== $handle ) {
foreach ( $config_file as $line ) {
fwrite( $handle, $line );
}
fclose( $handle );
} else {
$wp_config_perms = fileperms( $path_to_wp_config );
if ( ! empty( $wp_config_perms ) && ! is_writable( $path_to_wp_config ) ) {
$error_message = sprintf(
/* translators: 1: wp-config.php, 2: Documentation URL. */
__( 'You need to make the file %1$s writable before you can save your changes. See <a href="%2$s">Changing File Permissions</a> for more information.' ),
'<code>wp-config.php</code>',
__( 'https://wordpress.org/support/article/changing-file-permissions/' )
);
} else {
$error_message = sprintf(
/* translators: %s: wp-config.php */
__( 'Unable to write to %s file.' ),
'<code>wp-config.php</code>'
);
}
}
chmod( $path_to_wp_config, 0666 );
setup_config_display_header();
//clean install-key.php file
unlink( ABSPATH . '/install-key.php' );
if ( false !== $handle ) :
?>
<h1 class="screen-reader-text"><?php _e( 'Successful database connection' ); ?></h1>
<p><?php _e( 'All right, sparky! You&#8217;ve made it through this part of the installation. WordPress can now communicate with your database. If you are ready, time now to&hellip;' ); ?></p>
<p class="step"><a href="<?php echo $install; ?>" class="button button-large"><?php _e( 'Run the installation' ); ?></a></p>
<?php
else :
printf( '<p>%s</p>', $error_message );
endif;
endif;
break;
} // End of the steps switch.
?>
<?php wp_print_scripts( 'language-chooser' ); ?>
</body>
</html>
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