<?php
/**
* Error Protection API: WP_Recovery_Mode_Key_Service class
*
* @package WordPress
* @since 5.2.0
*/

/**
* Core class used to generate and validate keys used to enter Recovery Mode.
*
* @since 5.2.0
*/
#[AllowDynamicProperties]
final class WP_Recovery_Mode_Key_Service {

/**
* The option name used to store the keys.
*
* @since 5.2.0
* @var string
*/
private $option_name = 'recovery_keys';

/**
* Creates a recovery mode token.
*
* @since 5.2.0
*
* @return string A random string to identify its associated key in storage.
*/
public function generate_recovery_mode_token() {
return wp_generate_password( 22, false );
}

/**
* Creates a recovery mode key.
*
* @since 5.2.0
*
* @global PasswordHash $wp_hasher Portable PHP password hashing framework instance.
*
* @param string $token A token generated by {@see generate_recovery_mode_token()}.
* @return string Recovery mode key.
*/
public function generate_and_store_recovery_mode_key( $token ) {

global $wp_hasher;

$key = wp_generate_password( 22, false );

if ( empty( $wp_hasher ) ) {
require_once ABSPATH . WPINC . '/class-phpass.php';
$wp_hasher = new PasswordHash( 8, true );
}

$hashed = $wp_hasher->HashPassword( $key );

$records = $this->get_keys();

$records[ $token ] = array(
'hashed_key' => $hashed,
'created_at' => time(),
);

$this->update_keys( $records );

/**
* Fires when a recovery mode key is generated.
*
* @since 5.2.0
*
* @param string $token The recovery data token.
* @param string $key The recovery mode key.
*/
do_action( 'generate_recovery_mode_key', $token, $key );

return $key;
}

/**
* Verifies if the recovery mode key is correct.
*
* Recovery mode keys can only be used once; the key will be consumed in the process.
*
* @since 5.2.0
*
* @global PasswordHash $wp_hasher Portable PHP password hashing framework instance.
*
* @param string $token The token used when generating the given key.
* @param string $key The unhashed key.
* @param int $ttl Time in seconds for the key to be valid for.
* @return true|WP_Error True on success, error object on failure.
*/
public function validate_recovery_mode_key( $token, $key, $ttl ) {
global $wp_hasher;

$records = $this->get_keys();

if ( ! isset( $records[ $token ] ) ) {
return new WP_Error( 'token_not_found', __( 'Recovery Mode not initialized.' ) );
}

$record = $records[ $token ];

$this->remove_key( $token );

if ( ! is_array( $record ) || ! isset( $record['hashed_key'], $record['created_at'] ) ) {
return new WP_Error( 'invalid_recovery_key_format', __( 'Invalid recovery key format.' ) );
}

if ( empty( $wp_hasher ) ) {
require_once ABSPATH . WPINC . '/class-phpass.php';
$wp_hasher = new PasswordHash( 8, true );
}

if ( ! $wp_hasher->CheckPassword( $key, $record['hashed_key'] ) ) {
return new WP_Error( 'hash_mismatch', __( 'Invalid recovery key.' ) );
}

if ( time() > $record['created_at'] + $ttl ) {
return new WP_Error( 'key_expired', __( 'Recovery key expired.' ) );
}

return true;
}

/**
* Removes expired recovery mode keys.
*
* @since 5.2.0
*
* @param int $ttl Time in seconds for the keys to be valid for.
*/
public function clean_expired_keys( $ttl ) {

$records = $this->get_keys();

foreach ( $records as $key => $record ) {
if ( ! isset( $record['created_at'] ) || time() > $record['created_at'] + $ttl ) {
unset( $records[ $key ] );
}
}

$this->update_keys( $records );
}

/**
* Removes a used recovery key.
*
* @since 5.2.0
*
* @param string $token The token used when generating a recovery mode key.
*/
private function remove_key( $token ) {

$records = $this->get_keys();

if ( ! isset( $records[ $token ] ) ) {
return;
}

unset( $records[ $token ] );

$this->update_keys( $records );
}

/**
* Gets the recovery key records.
*
* @since 5.2.0
*
* @return array Associative array of $token => $data pairs, where $data has keys 'hashed_key'
* and 'created_at'.
*/
private function get_keys() {
return (array) get_option( $this->option_name, array() );
}

/**
* Updates the recovery key records.
*
* @since 5.2.0
*
* @param array $keys Associative array of $token => $data pairs, where $data has keys 'hashed_key'
* and 'created_at'.
* @return bool True on success, false on failure.
*/
private function update_keys( array $keys ) {
return update_option( $this->option_name, $keys, false );
}
}