[#3680] Enabled SecurityManager results in ClassNotFoundError during io.netty.util.NetUtil initialization

Motivation:

When a SecurityManager is in place that preven reading the somaxconn file trying to bootstrap a channel later will result in a ClassNotFoundError.

Modifications:

- Reading the file in a privileged block.

Result:

No more ClassNotFoundError when a SecurityManager is in place.
This commit is contained in:
Norman Maurer 2015-04-23 12:14:49 +02:00
parent 4baea3ea7a
commit 18ace807b8

View File

@ -29,6 +29,8 @@ import java.net.InetAddress;
import java.net.NetworkInterface; import java.net.NetworkInterface;
import java.net.SocketException; import java.net.SocketException;
import java.net.UnknownHostException; import java.net.UnknownHostException;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.ArrayList; import java.util.ArrayList;
import java.util.Enumeration; import java.util.Enumeration;
import java.util.List; import java.util.List;
@ -231,38 +233,45 @@ public final class NetUtil {
LOOPBACK_IF = loopbackIface; LOOPBACK_IF = loopbackIface;
LOCALHOST = loopbackAddr; LOCALHOST = loopbackAddr;
// Determine the default somaxconn (server socket backlog) value of the platform. // As a SecurityManager may prevent reading the somaxconn file we wrap this in a privileged block.
// The known defaults: //
// - Windows NT Server 4.0+: 200 // See https://github.com/netty/netty/issues/3680
// - Linux and Mac OS X: 128 SOMAXCONN = AccessController.doPrivileged(new PrivilegedAction<Integer>() {
int somaxconn = PlatformDependent.isWindows() ? 200 : 128; @Override
File file = new File("/proc/sys/net/core/somaxconn"); public Integer run() {
if (file.exists()) { // Determine the default somaxconn (server socket backlog) value of the platform.
BufferedReader in = null; // The known defaults:
try { // - Windows NT Server 4.0+: 200
in = new BufferedReader(new FileReader(file)); // - Linux and Mac OS X: 128
somaxconn = Integer.parseInt(in.readLine()); int somaxconn = PlatformDependent.isWindows() ? 200 : 128;
if (logger.isDebugEnabled()) { File file = new File("/proc/sys/net/core/somaxconn");
logger.debug("{}: {}", file, somaxconn); if (file.exists()) {
} BufferedReader in = null;
} catch (Exception e) {
logger.debug("Failed to get SOMAXCONN from: {}", file, e);
} finally {
if (in != null) {
try { try {
in.close(); in = new BufferedReader(new FileReader(file));
somaxconn = Integer.parseInt(in.readLine());
if (logger.isDebugEnabled()) {
logger.debug("{}: {}", file, somaxconn);
}
} catch (Exception e) { } catch (Exception e) {
// Ignored. logger.debug("Failed to get SOMAXCONN from: {}", file, e);
} finally {
if (in != null) {
try {
in.close();
} catch (Exception e) {
// Ignored.
}
}
}
} else {
if (logger.isDebugEnabled()) {
logger.debug("{}: {} (non-existent)", file, somaxconn);
} }
} }
return somaxconn;
} }
} else { });
if (logger.isDebugEnabled()) {
logger.debug("{}: {} (non-existent)", file, somaxconn);
}
}
SOMAXCONN = somaxconn;
} }
/** /**