Class IpTables

solr/test-framework/src/java/org/apache/solr/cloud/IpTables.java:28–62

To use, tests must be able to run iptables, eg sudo chmod u+s iptables

/** To use, tests must be able to run iptables, eg sudo chmod u+s iptables */
public class IpTables {
  private static final Logger log = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());

  private static final boolean ENABLED = Boolean.getBoolean("solr.tests.use.iptables");

  private static final Set<Integer> BLOCK_PORTS =
      Collections.synchronizedSet(new HashSet<Integer>());

  public static void unblockPort(int port) throws IOException, InterruptedException {
    if (ENABLED && BLOCK_PORTS.contains(port)) {
      log.info("Unblock port with iptables: {}", port);
      runCmd(("iptables -D INPUT -p tcp --dport " + port + " -j DROP").split("\\s"));
      runCmd(("iptables -D OUTPUT -p tcp --dport " + port + " -j DROP").split("\\s"));
      BLOCK_PORTS.remove(port);
    }
  }

  public static void unblockAllPorts() throws IOException, InterruptedException {
    if (ENABLED) {
      log.info("Unblocking any ports previously blocked with iptables...");
      final Integer[] ports = BLOCK_PORTS.toArray(new Integer[0]);
      for (Integer port : ports) {
        IpTables.unblockPort(port);
      }
    }
  }

  private static void runCmd(String... cmd) throws IOException, InterruptedException {
    final int exitCode = new ProcessBuilder(cmd).inheritIO().start().waitFor();
    if (exitCode != 0) {
      throw new IOException(
          "iptables process did not exit successfully, exit code was: " + exitCode);
    }
  }
}