Delete user meta on plugin uninstall

class-two-factor-core.php

@@ -132,13 +132,82 @@ public static function add_hooks( $compat ) {
 	}
 
 	/**
-	 * For each provider, include it and then instantiate it.
+	 * Delete all plugin data on uninstall.
 	 *
-	 * @since 0.1-dev
+	 * @return void
+	 */
+	public static function uninstall() {
+		// Keep this updated as user meta keys are added or removed.
+		$user_meta_keys = array(
+			self::PROVIDER_USER_META_KEY,
+			self::ENABLED_PROVIDERS_USER_META_KEY,
+			self::USER_META_NONCE_KEY,
+			self::USER_RATE_LIMIT_KEY,
+			self::USER_FAILED_LOGIN_ATTEMPTS_KEY,
+			self::USER_PASSWORD_WAS_RESET_KEY,
+		);
+
+		$option_keys = array();
+
+		foreach ( self::get_providers_classes() as $provider_class ) {
+			// Merge with provider-specific user meta keys.
+			if ( method_exists( $provider_class, 'uninstall_user_meta_keys' ) ) {
+				try {
+					$user_meta_keys = array_merge(
+						$user_meta_keys,
+						call_user_func( array( $provider_class, 'uninstall_user_meta_keys' ) )
+					);
+				} catch ( Exception $e ) {
+					// Do nothing.
+				}
+			}
+
+			// Merge with provider-specific option keys.
+			if ( method_exists( $provider_class, 'uninstall_options' ) ) {
+				try {
+					$option_keys = array_merge(
+						$option_keys,
+						call_user_func( array( $provider_class, 'uninstall_options' ) )
+					);
+				} catch ( Exception $e ) {
+					// Do nothing.
+				}
+			}
+		}
+
+		// Delete options first since that is faster.
+		if ( ! empty( $option_keys ) ) {
+			foreach ( $option_keys as $option_key ) {
+				delete_option( $option_key );
+			}
+		}
+
+		/**
+		 * Get all user IDs to delete their user meta.
+		 *
+		 * Consider replacing this with a direct SQL query to speed up the process.
+		 */
+		$user_ids = get_users(
+			array(
+				'blog_id' => 0, // Return all users.
+				'fields' => 'ID',
+				'number' => -1, // This might take a while on larger sites but we have only one uninstall hook to run this.
+			)
+		);
+
+		foreach ( $user_ids as $user_id ) {
+			foreach ( $user_meta_keys as $meta_key ) {
+				delete_user_meta( $user_id, $meta_key );
+			}
+		}
+	}
+
+	/**
+	 * Get the registered providers of which some might not be enabled.
 	 *
-	 * @return array
+	 * @return array List of provider keys and paths to class files.
 	 */
-	public static function get_providers() {
+	public static function get_providers_registered() {
 		$providers = array(
 			'Two_Factor_Email'        => TWO_FACTOR_DIR . 'providers/class-two-factor-email.php',
 			'Two_Factor_Totp'         => TWO_FACTOR_DIR . 'providers/class-two-factor-totp.php',
@@ -150,29 +219,29 @@ public static function get_providers() {
 		/**
 		 * Filter the supplied providers.
 		 *
-		 * This lets third-parties either remove providers (such as Email), or
-		 * add their own providers (such as text message or Clef).
-		 *
 		 * @param array $providers A key-value array where the key is the class name, and
 		 *                         the value is the path to the file containing the class.
 		 */
-		$providers = apply_filters( 'two_factor_providers', $providers );
+		$additional_providers = apply_filters( 'two_factor_providers', $providers );
 
-		// FIDO U2F is PHP 5.3+ only.
-		if ( isset( $providers['Two_Factor_FIDO_U2F'] ) && version_compare( PHP_VERSION, '5.3.0', '<' ) ) {
-			unset( $providers['Two_Factor_FIDO_U2F'] );
-			trigger_error( // phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_trigger_error
-				sprintf(
-				/* translators: %s: version number */
-					__( 'FIDO U2F is not available because you are using PHP %s. (Requires 5.3 or greater)', 'two-factor' ), // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
-					PHP_VERSION
-				)
-			);
+		// Merge them with the default providers.
+		if ( ! empty( $additional_providers ) ) {
+			return array_merge( $providers, $additional_providers );
 		}
 
-		/**
-		 * For each filtered provider,
-		 */
+		return $providers;
+	}
+
+	/**
+	 * Get the classnames for all registered providers.
+	 *
+	 * Note some of these providers might not be enabled.
+	 *
+	 * @return array List of provider keys and classnames.
+	 */
+	private static function get_providers_classes() {
+		$providers = self::get_providers_registered();
+
 		foreach ( $providers as $provider_key => $path ) {
 			require_once $path;
 
@@ -189,9 +258,56 @@ public static function get_providers() {
 			/**
 			 * Confirm that it's been successfully included before instantiating.
 			 */
-			if ( class_exists( $class ) ) {
+			if ( method_exists( $class, 'get_instance' ) ) {
+				$providers[ $provider_key ] = $class;
+			} else {
+				unset( $providers[ $provider_key ] );
+			}
+		}
+
+		return $providers;
+	}
+
+	/**
+	 * Get all enabled two-factor providers.
+	 *
+	 * @since 0.1-dev
+	 *
+	 * @return array
+	 */
+	public static function get_providers() {
+		$providers = self::get_providers_registered();
+
+		/**
+		 * Filter the supplied providers.
+		 *
+		 * This lets third-parties either remove providers (such as Email), or
+		 * add their own providers (such as text message or Clef).
+		 *
+		 * @param array $providers A key-value array where the key is the class name, and
+		 *                         the value is the path to the file containing the class.
+		 */
+		$providers = apply_filters( 'two_factor_providers', $providers );
+
+		// FIDO U2F is PHP 5.3+ only.
+		if ( isset( $providers['Two_Factor_FIDO_U2F'] ) && version_compare( PHP_VERSION, '5.3.0', '<' ) ) {
+			unset( $providers['Two_Factor_FIDO_U2F'] );
+			trigger_error( // phpcs:ignore WordPress.PHP.DevelopmentFunctions.error_log_trigger_error
+				sprintf(
+				/* translators: %s: version number */
+					__( 'FIDO U2F is not available because you are using PHP %s. (Requires 5.3 or greater)', 'two-factor' ), // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
+					PHP_VERSION
+				)
+			);
+		}
+
+		// Map provider keys to classes so that we can instantiate them.
+		$providers = array_intersect_key( self::get_providers_classes(), $providers );
+
+		foreach ( $providers as $provider_key => $provider_class ) {
+			if ( method_exists( $provider_class, 'get_instance' ) ) {
 				try {
-					$providers[ $provider_key ] = call_user_func( array( $class, 'get_instance' ) );
+					$providers[ $provider_key ] = call_user_func( array( $provider_class, 'get_instance' ) );
 				} catch ( Exception $e ) {
 					unset( $providers[ $provider_key ] );
 				}

providers/class-two-factor-backup-codes.php

@@ -399,4 +399,15 @@ public function delete_code( $user, $code_hashed ) {
 		// Update the backup code master list.
 		update_user_meta( $user->ID, self::BACKUP_CODES_META_KEY, $backup_codes );
 	}
+
+	/**
+	 * Return user meta keys to delete during plugin uninstall.
+	 *
+	 * @return array
+	 */
+	public static function uninstall_user_meta_keys() {
+		return array(
+			self::BACKUP_CODES_META_KEY,
+		);
+	}
 }

providers/class-two-factor-email.php

@@ -351,4 +351,16 @@ public function user_options( $user ) {
 		</div>
 		<?php
 	}
+
+	/**
+	 * Return user meta keys to delete during plugin uninstall.
+	 *
+	 * @return array
+	 */
+	public static function uninstall_user_meta_keys() {
+		return array(
+			self::TOKEN_META_KEY,
+			self::TOKEN_META_KEY_TIMESTAMP,
+		);
+	}
 }

providers/class-two-factor-fido-u2f.php

@@ -388,4 +388,17 @@ public static function delete_security_key( $user_id, $keyHandle = null ) { // p
 
 		return true;
 	}
+
+	/**
+	 * Return user meta keys to delete during plugin uninstall.
+	 *
+	 * @return array
+	 */
+	public static function uninstall_user_meta_keys() {
+		return array(
+			self::REGISTERED_KEY_USER_META_KEY,
+			self::AUTH_DATA_USER_META_KEY,
+			'_two_factor_fido_u2f_register_request', // From Two_Factor_FIDO_U2F_Admin which is not loaded during uninstall.
+		);
+	}
 }

providers/class-two-factor-provider.php

@@ -165,4 +165,24 @@ public static function sanitize_code_from_request( $field, $length = 0 ) {
 
 		return (string) $code;
 	}
+
+	/**
+	 * Return the user meta keys that need to be deletated on plugin uninstall.
+	 *
+	 * @return array
+	 */
+	public static function uninstall_user_meta_keys() {
+		return array();
+	}
+
+	/**
+	 * Return the option keys that need to be deleted on plugin uninstall.
+	 *
+	 * Note: this method doesn't have access to the instantiated provider object.
+	 *
+	 * @return array
+	 */
+	public static function uninstall_options() {
+		return array();
+	}
 }

providers/class-two-factor-totp.php

@@ -771,4 +771,16 @@ private static function abssort( $a, $b ) {
 		}
 		return ( $a < $b ) ? -1 : 1;
 	}
+
+	/**
+	 * Return user meta keys to delete during plugin uninstall.
+	 *
+	 * @return array
+	 */
+	public static function uninstall_user_meta_keys() {
+		return array(
+			self::SECRET_META_KEY,
+			self::LAST_SUCCESSFUL_LOGIN_META_KEY,
+		);
+	}
 }

two-factor.php

@@ -50,3 +50,6 @@
 $two_factor_compat = new Two_Factor_Compat();
 
 Two_Factor_Core::add_hooks( $two_factor_compat );
+
+// Delete our options and user meta during uninstall.
+register_uninstall_hook( __FILE__, array( Two_Factor_Core::class, 'uninstall' ) );