SSLServerSocketFactorys create
* SSLServerSockets.
*
* @since 1.4
* @see SSLSocket
* @see SSLServerSocket
* @author David Brownell
*/
public abstract class SSLServerSocketFactory extends ServerSocketFactory
{
private static SSLServerSocketFactory defaultServerSocketFactory;
private static int lastVersion = -1;
private static void log(String msg) {
if (SSLSocketFactory.DEBUG) {
System.out.println(msg);
}
}
/**
* Constructor is used only by subclasses.
*/
protected SSLServerSocketFactory() { /* NOTHING */ }
/**
* Returns the default SSL server socket factory.
*
* The first time this method is called, the security property * "ssl.ServerSocketFactory.provider" is examined. If it is non-null, a * class by that name is loaded and instantiated. If that is successful and * the object is an instance of SSLServerSocketFactory, it is made the * default SSL server socket factory. * *
Otherwise, this method returns
* SSLContext.getDefault().getServerSocketFactory(). If that
* call fails, an inoperative factory is returned.
*
* @return the default ServerSocketFactory
* @see SSLContext#getDefault
*/
public static synchronized ServerSocketFactory getDefault() {
// Android-changed: Use security version instead of propertyChecked.
//
// We use the same lookup logic in SSLSocketFactory.getDefault(). Any changes
// made here must be mirrored in that class.
if (defaultServerSocketFactory != null && lastVersion == Security.getVersion()) {
return defaultServerSocketFactory;
}
lastVersion = Security.getVersion();
SSLServerSocketFactory previousDefaultServerSocketFactory = defaultServerSocketFactory;
defaultServerSocketFactory = null;
String clsName = SSLSocketFactory.getSecurityProperty
("ssl.ServerSocketFactory.provider");
if (clsName != null) {
// The instance for the default socket factory is checked for updates quite
// often (for instance, every time a security provider is added). Which leads
// to unnecessary overload and excessive error messages in case of class-loading
// errors. Avoid creating a new object if the class name is the same as before.
if (previousDefaultServerSocketFactory != null
&& clsName.equals(previousDefaultServerSocketFactory.getClass().getName())) {
defaultServerSocketFactory = previousDefaultServerSocketFactory;
return defaultServerSocketFactory;
}
Class cls = null;
log("setting up default SSLServerSocketFactory");
try {
log("setting up default SSLServerSocketFactory");
try {
cls = Class.forName(clsName);
} catch (ClassNotFoundException e) {
// Android-changed; Try the contextClassLoader first.
ClassLoader cl = Thread.currentThread().getContextClassLoader();
if (cl == null) {
cl = ClassLoader.getSystemClassLoader();
}
if (cl != null) {
cls = Class.forName(clsName, true, cl);
}
}
log("class " + clsName + " is loaded");
SSLServerSocketFactory fac = (SSLServerSocketFactory) cls.newInstance();
log("instantiated an instance of class " + clsName);
defaultServerSocketFactory = fac;
if (defaultServerSocketFactory != null) {
return defaultServerSocketFactory;
}
} catch (Exception e) {
log("SSLServerSocketFactory instantiation failed: " + e);
// Android-changed: Fallback to the default SSLContext if an exception
// is thrown during the initialization of ssl.ServerSocketFactory.provider.
}
}
try {
SSLContext context = SSLContext.getDefault();
if (context != null) {
defaultServerSocketFactory = context.getServerSocketFactory();
}
} catch (NoSuchAlgorithmException e) {
}
if (defaultServerSocketFactory == null) {
defaultServerSocketFactory = new DefaultSSLServerSocketFactory(
new IllegalStateException("No ServerSocketFactory implementation found"));
}
return defaultServerSocketFactory;
}
/**
* Returns the list of cipher suites which are enabled by default.
* Unless a different list is enabled, handshaking on an SSL connection
* will use one of these cipher suites. The minimum quality of service
* for these defaults requires confidentiality protection and server
* authentication (that is, no anonymous cipher suites).
*
* @see #getSupportedCipherSuites()
* @return array of the cipher suites enabled by default
*/
public abstract String [] getDefaultCipherSuites();
/**
* Returns the names of the cipher suites which could be enabled for use
* on an SSL connection created by this factory.
* Normally, only a subset of these will actually
* be enabled by default, since this list may include cipher suites which
* do not meet quality of service requirements for those defaults. Such
* cipher suites are useful in specialized applications.
*
* @return an array of cipher suite names
* @see #getDefaultCipherSuites()
*/
public abstract String [] getSupportedCipherSuites();
}
//
// The default factory does NOTHING.
//
class DefaultSSLServerSocketFactory extends SSLServerSocketFactory {
private final Exception reason;
DefaultSSLServerSocketFactory(Exception reason) {
this.reason = reason;
}
private ServerSocket throwException() throws SocketException {
throw (SocketException)
new SocketException(reason.toString()).initCause(reason);
}
public ServerSocket createServerSocket() throws IOException {
return throwException();
}
public ServerSocket createServerSocket(int port)
throws IOException
{
return throwException();
}
public ServerSocket createServerSocket(int port, int backlog)
throws IOException
{
return throwException();
}
public ServerSocket
createServerSocket(int port, int backlog, InetAddress ifAddress)
throws IOException
{
return throwException();
}
public String [] getDefaultCipherSuites() {
return new String[0];
}
public String [] getSupportedCipherSuites() {
return new String[0];
}
}