Changeset 43082 for branches/4.9/src/wp-includes/functions.php

Timestamp:

05/02/2018 12:48:23 AM (8 years ago)

Author:

SergeyBiryukov

Message:

Privacy: add helper function for anonymizing data in a standardized way.

Props jesperher, allendav, iandunn, birgire, azaozz, joemcgill.
Merges [42971] and [43081] to the 4.9 branch.
Fixes #43545.

Location:

branches/4.9

Files:

• . (modified) (1 prop)
• src/wp-includes/functions.php (modified) (1 diff)

branches/4.9/src/wp-includes/functions.php

@@ -5817 +5817 @@
         ), $email_change_email['message'], $email_change_email['headers'] );
 }
+
+/**
+ * Return an anonymized IPv4 or IPv6 address.
+ *
+ * @since 4.9.6 Abstracted from `WP_Community_Events::get_unsafe_client_ip()`.
+ *
+ * @param  string $ip_addr        The IPv4 or IPv6 address to be anonymized.
+ * @param  bool   $ipv6_fallback  Optional. Whether to return the original IPv6 address if the needed functions
+ *                                to anonymize it are not present. Default false, return `::` (unspecified address).
+ * @return string  The anonymized IP address.
+ */
+function wp_privacy_anonymize_ip( $ip_addr, $ipv6_fallback = false ) {
+        // Detect what kind of IP address this is.
+        $ip_prefix = '';
+        $is_ipv6   = substr_count( $ip_addr, ':' ) > 1;
+        $is_ipv4   = ( 3 === substr_count( $ip_addr, '.' ) );
+
+        if ( $is_ipv6 && $is_ipv4 ) {
+                // IPv6 compatibility mode, temporarily strip the IPv6 part, and treat it like IPv4.
+                $ip_prefix = '::ffff:';
+                $ip_addr   = preg_replace( '/^\[?[0-9a-f:]*:/i', '', $ip_addr );
+                $ip_addr   = str_replace( ']', '', $ip_addr );
+                $is_ipv6   = false;
+        }
+
+        if ( $is_ipv6 ) {
+                // IPv6 addresses will always be enclosed in [] if there's a port.
+                $left_bracket  = strpos( $ip_addr, '[' );
+                $right_bracket = strpos( $ip_addr, ']' );
+                $percent       = strpos( $ip_addr, '%' );
+                $netmask       = 'ffff:ffff:ffff:ffff:0000:0000:0000:0000';
+
+                // Strip the port (and [] from IPv6 addresses), if they exist.
+                if ( false !== $left_bracket && false !== $right_bracket ) {
+                        $ip_addr = substr( $ip_addr, $left_bracket + 1, $right_bracket - $left_bracket - 1 );
+                } elseif ( false !== $left_bracket || false !== $right_bracket ) {
+                        // The IP has one bracket, but not both, so it's malformed.
+                        return '::';
+                }
+
+                // Strip the reachability scope.
+                if ( false !== $percent ) {
+                        $ip_addr = substr( $ip_addr, 0, $percent );
+                }
+
+                // No invalid characters should be left.
+                if ( preg_match( '/[^0-9a-f:]/i', $ip_addr ) ) {
+                        return '::';
+                }
+
+                // Partially anonymize the IP by reducing it to the corresponding network ID.
+                if ( function_exists( 'inet_pton' ) && function_exists( 'inet_ntop' ) ) {
+                        $ip_addr = inet_ntop( inet_pton( $ip_addr ) & inet_pton( $netmask ) );
+                        if ( false === $ip_addr) {
+                                return '::';
+                        }
+                } elseif ( ! $ipv6_fallback ) {
+                        return '::';
+                }
+        } elseif ( $is_ipv4 ) {
+                // Strip any port and partially anonymize the IP.
+                $last_octet_position = strrpos( $ip_addr, '.' );
+                $ip_addr             = substr( $ip_addr, 0, $last_octet_position ) . '.0';
+        } else {
+                return '0.0.0.0';
+        }
+
+        // Restore the IPv6 prefix to compatibility mode addresses.
+        return $ip_prefix . $ip_addr;
+}
+
+/**
+ * Return uniform "anonymous" data by type.
+ *
+ * @since 4.9.6
+ *
+ * @param  string $type The type of data to be anonymized.
+ * @param  string $data Optional The data to be anonymized.
+ * @return string The anonymous data for the requested type.
+ */
+function wp_privacy_anonymize_data( $type, $data = '' ) {
+
+        switch ( $type ) {
+                case 'email':
+                        $anonymous = 'deleted@site.invalid';
+                        break;
+                case 'url':
+                        $anonymous = 'https://site.invalid';
+                        break;
+                case 'ip':
+                        $anonymous = wp_privacy_anonymize_ip( $data );
+                        break;
+                case 'date':
+                        $anonymous = '0000-00-00 00:00:00';
+                        break;
+                case 'text':
+                        /* translators: deleted text */
+                        $anonymous = __( '[deleted]' );
+                        break;
+                case 'longtext':
+                        /* translators: deleted long text */
+                        $anonymous = __( 'This content was deleted by the author.' );
+                        break;
+                default:
+                        $anonymous = '';
+        }
+
+        /**
+         * Filters the anonymous data for each type.
+         *
+         * @since 4.9.6
+         *
+         * @param string $anonymous Anonymized data.
+         * @param string $type      Type of the data.
+         * @param string $data      Original data.
+         */
+        return apply_filters( 'wp_privacy_anonymize_data', $anonymous, $type, $data );
+}