Retrieves a user row based on password reset key and login

A key is considered ‘expired’ if it exactly matches the value of the user_activation_key field, rather than being matched after going through the hashing process. This field is now hashed; old values are no longer accepted but have a different WP_Error code so good user feedback can be provided.

Signature

check_password_reset_key( $key, $login )
key
 (string) Hash to validate sending user's password.
login
 (string) The user login.

Return

(WP_User|WP_Error) WP_User object on success, WP_Error object for invalid or expired keys.

Source

function check_password_reset_key($key, $login) {
	global $wpdb, $wp_hasher;

	$key = preg_replace('/[^a-z0-9]/i', '', $key);

	if ( empty( $key ) || !is_string( $key ) )
		return new WP_Error('invalid_key', __('Invalid key'));

	if ( empty($login) || !is_string($login) )
		return new WP_Error('invalid_key', __('Invalid key'));

	$row = $wpdb->get_row( $wpdb->prepare( "SELECT ID, user_activation_key FROM $wpdb->users WHERE user_login = %s", $login ) );
	if ( ! $row )
		return new WP_Error('invalid_key', __('Invalid key'));

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

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