Changeset 42971 for trunk/src/wp-includes/functions.php

Timestamp:

04/12/2018 09:19:24 PM (6 years ago)

Author:

azaozz

Message:

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

Props jesperher, allendav, iandunn, birgire, azaozz.
Fixes #43545.

File:

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

trunk/src/wp-includes/functions.php

@@ -6128 +6128 @@
     );
 }
+
+/**
+ * Return an anonymized IPv4 or IPv6 address.
+ *
+ * @since 5.0.0 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 5.0.0
+ *
+ * @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 5.0.0
+     *
+     * @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 );
+}