Due to the POODLE vulnerability, my server, hosted in Amazon AWS does no longer support SSLv3.
As a result, the first HTTPS connection my Android app does against the server results in an error when the connection was being established.
Error reading server response: javax.net.ssl.SSLHandshakeException: javax.net.ssl.SSLProtocolException: SSL handshake aborted: ssl=0x77d8ab68: Failure in SSL library, usually a protocol error
error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure (external/openssl/ssl/s23_clnt.c:741 0x7339ad74:0x00000000)
[....]
Caused by: javax.net.ssl.SSLHandshakeException: javax.net.ssl.SSLProtocolException: SSL handshake aborted: ssl=0x77d8ab68: Failure in SSL library, usually a protocol error
error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure (external/openssl/ssl/s23_clnt.c:741 0x7339ad74:0x00000000)
at com.android.org.conscrypt.OpenSSLSocketImpl.startHandshake(OpenSSLSocketImpl.java:448)
at com.android.okhttp.Connection.upgradeToTls(Connection.java:146)
at com.android.okhttp.Connection.connect(Connection.java:107)
at com.android.okhttp.internal.http.HttpEngine.connect(HttpEngine.java:294)
at com.android.okhttp.internal.http.HttpEngine.sendSocketRequest(HttpEngine.java:255)
at com.android.okhttp.internal.http.HttpEngine.sendRequest(HttpEngine.java:206)
The error happens only in the first request. Subsequent requests work for some time.
To fix this I'm trying to remove SSL from the list of protocols accepted by the Android client, and ensure I'm going only with TLS. To do this, I set a custom SSLSocketFactory which removes SSL from the list of enabled protocols and supported cypher suites.
/**
* SSLSocketFactory that wraps one existing SSLSocketFactory and delegetes into it adding
* a new cipher suite
*/
public class TLSOnlySocketFactory extends SSLSocketFactory {
private final SSLSocketFactory delegate;
public TLSOnlySocketFactory(SSLSocketFactory delegate) {
this.delegate = delegate;
}
@Override
public String[] getDefaultCipherSuites() {
return getPreferredDefaultCipherSuites(this.delegate);
}
@Override
public String[] getSupportedCipherSuites() {
return getPreferredSupportedCipherSuites(this.delegate);
}
@Override
public Socket createSocket(Socket s, String host, int port, boolean autoClose) throws IOException {
final Socket socket = this.delegate.createSocket(s, host, port, autoClose);
((SSLSocket)socket).setEnabledCipherSuites(getPreferredDefaultCipherSuites(delegate));
((SSLSocket)socket).setEnabledProtocols(getEnabledProtocols((SSLSocket)socket));
return socket;
}
[.....]
((SSLSocket)socket).setEnabledCipherSuites(getPreferredDefaultCipherSuites(delegate));
((SSLSocket) socket).setEnabledProtocols(getEnabledProtocols((SSLSocket)socket));
return socket;
}
@Override
public Socket createSocket(InetAddress host, int port) throws IOException {
final Socket socket = this.delegate.createSocket(host, port);
((SSLSocket)socket).setEnabledCipherSuites(getPreferredDefaultCipherSuites(delegate));
((SSLSocket) socket).setEnabledProtocols(getEnabledProtocols((SSLSocket)socket));
return socket;
}
@Override
public Socket createSocket(InetAddress address, int port, InetAddress localAddress, int localPort) throws IOException {
final Socket socket = this.delegate.createSocket(address, port, localAddress, localPort);
((SSLSocket)socket).setEnabledCipherSuites(getPreferredDefaultCipherSuites(delegate));
((SSLSocket) socket).setEnabledProtocols(getEnabledProtocols((SSLSocket)socket));
return socket;
}
private String[] getPreferredDefaultCipherSuites(SSLSocketFactory sslSocketFactory) {
return getCipherSuites(sslSocketFactory.getDefaultCipherSuites());
}
private String[] getPreferredSupportedCipherSuites(SSLSocketFactory sslSocketFactory) {
return getCipherSuites(sslSocketFactory.getSupportedCipherSuites());
}
private String[] getCipherSuites(String[] cipherSuites) {
final ArrayList<String> suitesList = new ArrayList<String>(Arrays.asList(cipherSuites));
final Iterator<String> iterator = suitesList.iterator();
while (iterator.hasNext()) {
final String cipherSuite = iterator.next();
if (cipherSuite.contains("SSL")) {
iterator.remove();
}
}
return suitesList.toArray(new String[suitesList.size()]);
}
private String[] getEnabledProtocols(SSLSocket socket) {
final ArrayList<String> protocolList = new ArrayList<String>(Arrays.asList(socket.getSupportedProtocols()));
final Iterator<String> iterator = protocolList.iterator();
while (iterator.hasNext()) {
final String protocl = iterator.next();
if (protocl.contains("SSL")) {
iterator.remove();
}
}
return protocolList.toArray(new String[protocolList.size()]);
}
}
As you see, my SSLSocketFactory delegates into another SSLSocketFactory and what it does is simply removing SSL from the list of enabled protocols.
I establish this factory as
final TLSOnlySocketFactory tlsOnlySocketFactory = new TLSOnlySocketFactory(HttpsURLConnection.getDefaultSSLSocketFactory());
HttpsURLConnection.setDefaultSSLSocketFactory(tlsOnlySocketFactory);
This does NOT fix the issue. From time to time, I still see the error when the connection was established. Oddly enough, this does not fix it, but it clearly minimises the occurrences of the issue.
How could I force the HttpsUrlConnection in my Android client to use only TLS?
Thank you.