Java tutorial
/******************************************************************************* * Copyright (C) 2015 yvolk (Yuri Volkov), http://yurivolkov.com - Insecure connection added * Copyright (c) 2014 Ricki Hirner (bitfire web engineering). * All rights reserved. This program and the accompanying materials * are made available under the terms of the GNU Public License v3.0 * which accompanies this distribution, and is available at * http://www.gnu.org/licenses/gpl.html * ******************************************************************************/ package org.andstatus.app.net.http; import java.io.IOException; import java.net.InetSocketAddress; import java.net.Socket; import java.util.concurrent.ConcurrentHashMap; import javax.net.ssl.HostnameVerifier; import javax.net.ssl.SSLPeerUnverifiedException; import javax.net.ssl.SSLSession; import javax.net.ssl.SSLSocket; import android.annotation.TargetApi; import android.net.SSLCertificateSocketFactory; import android.os.Build; import org.andstatus.app.context.MyPreferences; import org.andstatus.app.util.MyLog; import org.apache.http.HttpHost; import org.apache.http.conn.socket.ConnectionSocketFactory; import org.apache.http.conn.socket.LayeredConnectionSocketFactory; import org.apache.http.conn.ssl.AllowAllHostnameVerifier; import org.apache.http.conn.ssl.BrowserCompatHostnameVerifier; import org.apache.http.protocol.HttpContext; public class TlsSniSocketFactory implements LayeredConnectionSocketFactory { private static final ConcurrentHashMap<SslModeEnum, TlsSniSocketFactory> instances = new ConcurrentHashMap<SslModeEnum, TlsSniSocketFactory>(); public static ConnectionSocketFactory getInstance(SslModeEnum sslMode) { if (!instances.containsKey(sslMode)) { instances.put(sslMode, new TlsSniSocketFactory(sslMode)); } return instances.get(sslMode); } public static void forget() { instances.clear(); } private final boolean secure; private final SSLCertificateSocketFactory sslSocketFactory; /* For SSL connections without HTTP(S) proxy: 1) createSocket() is called 2) connectSocket() is called which creates a new SSL connection 2a) SNI is set up, and then 2b) the connection is established, hands are shaken and certificate/host name are verified Layered sockets are used with HTTP(S) proxies: 1) a new plain socket is created by the HTTP library 2) the plain socket is connected to http://proxy:8080 3) a CONNECT request is sent to the proxy and the response is parsed 4) now, createLayeredSocket() is called which wraps an SSL socket around the proxy connection, doing all the set-up and verfication 4a) Because SSLSocket.createSocket(socket, ...) always does a handshake without allowing to set up SNI before, *** SNI is not available for layered connections *** (unless active by Android's defaults, which it isn't at the moment). */ public TlsSniSocketFactory(SslModeEnum sslMode) { secure = sslMode == SslModeEnum.SECURE; if (secure) { sslSocketFactory = (SSLCertificateSocketFactory) SSLCertificateSocketFactory .getDefault(MyPreferences.getConnectionTimeoutMs()); } else { sslSocketFactory = (SSLCertificateSocketFactory) SSLCertificateSocketFactory .getInsecure(MyPreferences.getConnectionTimeoutMs(), null); MyLog.i(this, "Insecure SSL allowed"); } } @Override public Socket createSocket(HttpContext context) throws IOException { return sslSocketFactory.createSocket(); } @Override public Socket connectSocket(int timeout, Socket plain, HttpHost host, InetSocketAddress remoteAddr, InetSocketAddress localAddr, HttpContext context) throws IOException { MyLog.d(this, "Preparing direct SSL connection (without proxy) to " + host); // we'll rather use an SSLSocket directly plain.close(); // create a plain SSL socket, but don't do hostname/certificate verification yet SSLSocket ssl = (SSLSocket) sslSocketFactory.createSocket(remoteAddr.getAddress(), host.getPort()); // connect, set SNI, shake hands, verify, print connection info connectWithSNI(ssl, host.getHostName()); return ssl; } @Override public Socket createLayeredSocket(Socket plain, String host, int port, HttpContext context) throws IOException { MyLog.d(this, "Preparing layered SSL connection (over proxy) to " + host); // create a layered SSL socket, but don't do hostname/certificate verification yet SSLSocket ssl = (SSLSocket) sslSocketFactory.createSocket(plain, host, port, true); // already connected, but verify host name again and print some connection info MyLog.w(this, "Setting SNI/TLSv1.2 will silently fail because the handshake is already done"); connectWithSNI(ssl, host); return ssl; } @TargetApi(Build.VERSION_CODES.JELLY_BEAN_MR1) private void connectWithSNI(SSLSocket ssl, String host) throws SSLPeerUnverifiedException { // set reasonable SSL/TLS settings before the handshake: // - enable all supported protocols (enables TLSv1.1 and TLSv1.2 on Android <4.4.3, if available) ssl.setEnabledProtocols(ssl.getSupportedProtocols()); // - set SNI host name if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1) { MyLog.d(this, "Using documented SNI with host name " + host); sslSocketFactory.setHostname(ssl, host); } else { MyLog.d(this, "No documented SNI support on Android <4.2, trying with reflection"); try { java.lang.reflect.Method setHostnameMethod = ssl.getClass().getMethod("setHostname", String.class); setHostnameMethod.invoke(ssl, host); } catch (Exception e) { MyLog.i(this, "SNI not useable", e); } } // verify hostname and certificate SSLSession session = ssl.getSession(); if (!session.isValid()) { MyLog.i(this, "Invalid session to host:'" + host + "'"); } HostnameVerifier hostnameVerifier = secure ? new BrowserCompatHostnameVerifier() : new AllowAllHostnameVerifier(); if (!hostnameVerifier.verify(host, session)) { throw new SSLPeerUnverifiedException("Cannot verify hostname: " + host); } MyLog.i(this, "Established " + session.getProtocol() + " connection with " + session.getPeerHost() + " using " + session.getCipherSuite()); } }