Android example source code file (HttpsConnection.java)

This example Android source code file (HttpsConnection.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" ^TM.

Java - Android tags/keywords

android, androidhttpclientconnection, basichttpparams, connect, content, headers, httphost, httpsconnection, io, ioexception, net, network, override, ssl, sslconnectionclosedbyuserexception, sslcontextimpl, sslsocket, string, trustmanager, x509certificate

The HttpsConnection.java Android example source code

/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.net.http;

import android.content.Context;
import android.util.Log;
import org.apache.harmony.xnet.provider.jsse.FileClientSessionCache;
import org.apache.harmony.xnet.provider.jsse.SSLClientSessionCache;
import org.apache.harmony.xnet.provider.jsse.SSLContextImpl;
import org.apache.http.Header;
import org.apache.http.HttpException;
import org.apache.http.HttpHost;
import org.apache.http.HttpStatus;
import org.apache.http.ParseException;
import org.apache.http.ProtocolVersion;
import org.apache.http.StatusLine;
import org.apache.http.message.BasicHttpRequest;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpParams;

import javax.net.ssl.SSLException;
import javax.net.ssl.SSLSocket;
import javax.net.ssl.SSLSocketFactory;
import javax.net.ssl.TrustManager;
import javax.net.ssl.X509TrustManager;
import java.io.File;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.security.KeyManagementException;
import java.security.cert.X509Certificate;

/**
 * A Connection connecting to a secure http server or tunneling through
 * a http proxy server to a https server.
 *
 * @hide
 */
public class HttpsConnection extends Connection {

    /**
     * SSL socket factory
     */
    private static SSLSocketFactory mSslSocketFactory = null;

    static {
        // This initialization happens in the zygote. It triggers some
        // lazy initialization that can will benefit later invocations of
        // initializeEngine().
        initializeEngine(null);
    }

    /**
     * @hide
     *
     * @param sessionDir directory to cache SSL sessions
     */
    public static void initializeEngine(File sessionDir) {
        try {
            SSLClientSessionCache cache = null;
            if (sessionDir != null) {
                Log.d("HttpsConnection", "Caching SSL sessions in "
                        + sessionDir + ".");
                cache = FileClientSessionCache.usingDirectory(sessionDir);
            }

            SSLContextImpl sslContext = new SSLContextImpl();

            // here, trust managers is a single trust-all manager
            TrustManager[] trustManagers = new TrustManager[] {
                new X509TrustManager() {
                    public X509Certificate[] getAcceptedIssuers() {
                        return null;
                    }

                    public void checkClientTrusted(
                        X509Certificate[] certs, String authType) {
                    }

                    public void checkServerTrusted(
                        X509Certificate[] certs, String authType) {
                    }
                }
            };

            sslContext.engineInit(null, trustManagers, null, cache, null);

            synchronized (HttpsConnection.class) {
                mSslSocketFactory = sslContext.engineGetSocketFactory();
            }
        } catch (KeyManagementException e) {
            throw new RuntimeException(e);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    private synchronized static SSLSocketFactory getSocketFactory() {
        return mSslSocketFactory;
    }

    /**
     * Object to wait on when suspending the SSL connection
     */
    private Object mSuspendLock = new Object();

    /**
     * True if the connection is suspended pending the result of asking the
     * user about an error.
     */
    private boolean mSuspended = false;

    /**
     * True if the connection attempt should be aborted due to an ssl
     * error.
     */
    private boolean mAborted = false;

    // Used when connecting through a proxy.
    private HttpHost mProxyHost;

    /**
     * Contructor for a https connection.
     */
    HttpsConnection(Context context, HttpHost host, HttpHost proxy,
                    RequestFeeder requestFeeder) {
        super(context, host, requestFeeder);
        mProxyHost = proxy;
    }

    /**
     * Sets the server SSL certificate associated with this
     * connection.
     * @param certificate The SSL certificate
     */
    /* package */ void setCertificate(SslCertificate certificate) {
        mCertificate = certificate;
    }

    /**
     * Opens the connection to a http server or proxy.
     *
     * @return the opened low level connection
     * @throws IOException if the connection fails for any reason.
     */
    @Override
    AndroidHttpClientConnection openConnection(Request req) throws IOException {
        SSLSocket sslSock = null;

        if (mProxyHost != null) {
            // If we have a proxy set, we first send a CONNECT request
            // to the proxy; if the proxy returns 200 OK, we negotiate
            // a secure connection to the target server via the proxy.
            // If the request fails, we drop it, but provide the event
            // handler with the response status and headers. The event
            // handler is then responsible for cancelling the load or
            // issueing a new request.
            AndroidHttpClientConnection proxyConnection = null;
            Socket proxySock = null;
            try {
                proxySock = new Socket
                    (mProxyHost.getHostName(), mProxyHost.getPort());

                proxySock.setSoTimeout(60 * 1000);

                proxyConnection = new AndroidHttpClientConnection();
                HttpParams params = new BasicHttpParams();
                HttpConnectionParams.setSocketBufferSize(params, 8192);

                proxyConnection.bind(proxySock, params);
            } catch(IOException e) {
                if (proxyConnection != null) {
                    proxyConnection.close();
                }

                String errorMessage = e.getMessage();
                if (errorMessage == null) {
                    errorMessage =
                        "failed to establish a connection to the proxy";
                }

                throw new IOException(errorMessage);
            }

            StatusLine statusLine = null;
            int statusCode = 0;
            Headers headers = new Headers();
            try {
                BasicHttpRequest proxyReq = new BasicHttpRequest
                    ("CONNECT", mHost.toHostString());

                // add all 'proxy' headers from the original request, we also need
                // to add 'host' header unless we want proxy to answer us with a
                // 400 Bad Request
                for (Header h : req.mHttpRequest.getAllHeaders()) {
                    String headerName = h.getName().toLowerCase();
                    if (headerName.startsWith("proxy") || headerName.equals("keep-alive")
                            || headerName.equals("host")) {
                        proxyReq.addHeader(h);
                    }
                }

                proxyConnection.sendRequestHeader(proxyReq);
                proxyConnection.flush();

                // it is possible to receive informational status
                // codes prior to receiving actual headers;
                // all those status codes are smaller than OK 200
                // a loop is a standard way of dealing with them
                do {
                    statusLine = proxyConnection.parseResponseHeader(headers);
                    statusCode = statusLine.getStatusCode();
                } while (statusCode < HttpStatus.SC_OK);
            } catch (ParseException e) {
                String errorMessage = e.getMessage();
                if (errorMessage == null) {
                    errorMessage =
                        "failed to send a CONNECT request";
                }

                throw new IOException(errorMessage);
            } catch (HttpException e) {
                String errorMessage = e.getMessage();
                if (errorMessage == null) {
                    errorMessage =
                        "failed to send a CONNECT request";
                }

                throw new IOException(errorMessage);
            } catch (IOException e) {
                String errorMessage = e.getMessage();
                if (errorMessage == null) {
                    errorMessage =
                        "failed to send a CONNECT request";
                }

                throw new IOException(errorMessage);
            }

            if (statusCode == HttpStatus.SC_OK) {
                try {
                    sslSock = (SSLSocket) getSocketFactory().createSocket(
                            proxySock, mHost.getHostName(), mHost.getPort(), true);
                } catch(IOException e) {
                    if (sslSock != null) {
                        sslSock.close();
                    }

                    String errorMessage = e.getMessage();
                    if (errorMessage == null) {
                        errorMessage =
                            "failed to create an SSL socket";
                    }
                    throw new IOException(errorMessage);
                }
            } else {
                // if the code is not OK, inform the event handler
                ProtocolVersion version = statusLine.getProtocolVersion();

                req.mEventHandler.status(version.getMajor(),
                                         version.getMinor(),
                                         statusCode,
                                         statusLine.getReasonPhrase());
                req.mEventHandler.headers(headers);
                req.mEventHandler.endData();

                proxyConnection.close();

                // here, we return null to indicate that the original
                // request needs to be dropped
                return null;
            }
        } else {
            // if we do not have a proxy, we simply connect to the host
            try {
                sslSock = (SSLSocket) getSocketFactory().createSocket();

                sslSock.setSoTimeout(SOCKET_TIMEOUT);
                sslSock.connect(new InetSocketAddress(mHost.getHostName(),
                        mHost.getPort()));
            } catch(IOException e) {
                if (sslSock != null) {
                    sslSock.close();
                }

                String errorMessage = e.getMessage();
                if (errorMessage == null) {
                    errorMessage = "failed to create an SSL socket";
                }

                throw new IOException(errorMessage);
            }
        }

        // do handshake and validate server certificates
        SslError error = CertificateChainValidator.getInstance().
            doHandshakeAndValidateServerCertificates(this, sslSock, mHost.getHostName());

        // Inform the user if there is a problem
        if (error != null) {
            // handleSslErrorRequest may immediately unsuspend if it wants to
            // allow the certificate anyway.
            // So we mark the connection as suspended, call handleSslErrorRequest
            // then check if we're still suspended and only wait if we actually
            // need to.
            synchronized (mSuspendLock) {
                mSuspended = true;
            }
            // don't hold the lock while calling out to the event handler
            boolean canHandle = req.getEventHandler().handleSslErrorRequest(error);
            if(!canHandle) {
                throw new IOException("failed to handle "+ error);
            }
            synchronized (mSuspendLock) {
                if (mSuspended) {
                    try {
                        // Put a limit on how long we are waiting; if the timeout
                        // expires (which should never happen unless you choose
                        // to ignore the SSL error dialog for a very long time),
                        // we wake up the thread and abort the request. This is
                        // to prevent us from stalling the network if things go
                        // very bad.
                        mSuspendLock.wait(10 * 60 * 1000);
                        if (mSuspended) {
                            // mSuspended is true if we have not had a chance to
                            // restart the connection yet (ie, the wait timeout
                            // has expired)
                            mSuspended = false;
                            mAborted = true;
                            if (HttpLog.LOGV) {
                                HttpLog.v("HttpsConnection.openConnection():" +
                                          " SSL timeout expired and request was cancelled!!!");
                            }
                        }
                    } catch (InterruptedException e) {
                        // ignore
                    }
                }
                if (mAborted) {
                    // The user decided not to use this unverified connection
                    // so close it immediately.
                    sslSock.close();
                    throw new SSLConnectionClosedByUserException("connection closed by the user");
                }
            }
        }

        // All went well, we have an open, verified connection.
        AndroidHttpClientConnection conn = new AndroidHttpClientConnection();
        BasicHttpParams params = new BasicHttpParams();
        params.setIntParameter(HttpConnectionParams.SOCKET_BUFFER_SIZE, 8192);
        conn.bind(sslSock, params);

        return conn;
    }

    /**
     * Closes the low level connection.
     *
     * If an exception is thrown then it is assumed that the connection will
     * have been closed (to the extent possible) anyway and the caller does not
     * need to take any further action.
     *
     */
    @Override
    void closeConnection() {
        // if the connection has been suspended due to an SSL error
        if (mSuspended) {
            // wake up the network thread
            restartConnection(false);
        }

        try {
            if (mHttpClientConnection != null && mHttpClientConnection.isOpen()) {
                mHttpClientConnection.close();
            }
        } catch (IOException e) {
            if (HttpLog.LOGV)
                HttpLog.v("HttpsConnection.closeConnection():" +
                          " failed closing connection " + mHost);
            e.printStackTrace();
        }
    }

    /**
     * Restart a secure connection suspended waiting for user interaction.
     */
    void restartConnection(boolean proceed) {
        if (HttpLog.LOGV) {
            HttpLog.v("HttpsConnection.restartConnection():" +
                      " proceed: " + proceed);
        }

        synchronized (mSuspendLock) {
            if (mSuspended) {
                mSuspended = false;
                mAborted = !proceed;
                mSuspendLock.notify();
            }
        }
    }

    @Override
    String getScheme() {
        return "https";
    }
}

/**
 * Simple exception we throw if the SSL connection is closed by the user.
 *
 * {@hide}
 */
class SSLConnectionClosedByUserException extends SSLException {

    public SSLConnectionClosedByUserException(String reason) {
        super(reason);
    }
}