Package org.mockserver.netty.proxy

Class MockServerIpTransparentHelper

java.lang.Object
org.mockserver.netty.proxy.MockServerIpTransparentHelper
public final class MockServerIpTransparentHelper extends Object
Wires the IP_TRANSPARENT socket option on the server bootstrap when TPROXY mode is enabled.

The IP_TRANSPARENT socket option (Linux SOL_IP = 0, IP_TRANSPARENT = 19) allows the listener socket to accept connections destined for any IP address, not just the local addresses of the host. This is required for the TPROXY iptables target to work: the kernel redirects traffic to the listener socket while preserving the original destination as the socket's local address.

On Netty epoll transport, this is exposed as io.netty.channel.epoll.EpollChannelOption.IP_TRANSPARENT. On NIO transport or non-Linux platforms, this method is a no-op (logs a debug message).

Usage: call applyIfEnabled(ServerBootstrap, Configuration) after constructing the ServerBootstrap and before binding. This is idempotent.

Requires: CAP_NET_ADMIN on the process. Without it, the setsockopt(IP_TRANSPARENT) call will fail with EPERM and the Netty channel bind will fail. This is expected in non-TPROXY deployments.

See Also:

  • Method Summary

    Modifier and Type
    Method
    Description
    static boolean
    applyIfEnabled(io.netty.bootstrap.ServerBootstrap bootstrap, org.mockserver.configuration.Configuration configuration)
    Applies the IP_TRANSPARENT channel option to the server bootstrap if TPROXY mode is enabled in configuration and the epoll transport is available.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Method Details

    • applyIfEnabled

      public static boolean applyIfEnabled(io.netty.bootstrap.ServerBootstrap bootstrap, org.mockserver.configuration.Configuration configuration)
      Applies the IP_TRANSPARENT channel option to the server bootstrap if TPROXY mode is enabled in configuration and the epoll transport is available.
      Parameters:
      bootstrap - the server bootstrap to configure
      configuration - the MockServer configuration
      Returns:
      true if the option was applied, false otherwise