/*
* Copyright (C) 2008 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 com.android.email.mail.transport;
import com.android.email.Email;
import com.android.email.mail.CertificateValidationException;
import com.android.email.mail.MessagingException;
import com.android.email.mail.Transport;
import android.util.Config;
import android.util.Log;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.SocketAddress;
import java.net.SocketException;
import java.net.URI;
import java.security.GeneralSecurityException;
import java.security.SecureRandom;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLException;
import javax.net.ssl.TrustManager;
/**
* This class implements the common aspects of "transport", one layer below the
* specific wire protocols such as POP3, IMAP, or SMTP.
*/
public class MailTransport implements Transport {
// TODO protected eventually
/*protected*/ public static final int SOCKET_CONNECT_TIMEOUT = 10000;
/*protected*/ public static final int SOCKET_READ_TIMEOUT = 60000;
private String mDebugLabel;
private String mHost;
private int mPort;
private String[] mUserInfoParts;
private int mConnectionSecurity;
private boolean mTrustCertificates;
private Socket mSocket;
private InputStream mIn;
private OutputStream mOut;
/**
* Simple constructor for starting from scratch. Call setUri() and setSecurity() to
* complete the configuration.
* @param debugLabel Label used for Log.d calls
*/
public MailTransport(String debugLabel) {
super();
mDebugLabel = debugLabel;
}
/**
* Get a new transport, using an existing one as a model. The new transport is configured as if
* setUri() and setSecurity() have been called, but not opened or connected in any way.
* @return a new Transport ready to open()
*/
public Transport newInstanceWithConfiguration() {
MailTransport newObject = new MailTransport(mDebugLabel);
newObject.mDebugLabel = mDebugLabel;
newObject.mHost = mHost;
newObject.mPort = mPort;
if (mUserInfoParts != null) {
newObject.mUserInfoParts = mUserInfoParts.clone();
}
newObject.mConnectionSecurity = mConnectionSecurity;
newObject.mTrustCertificates = mTrustCertificates;
return newObject;
}
public void setUri(URI uri, int defaultPort) {
mHost = uri.getHost();
mPort = defaultPort;
if (uri.getPort() != -1) {
mPort = uri.getPort();
}
if (uri.getUserInfo() != null) {
mUserInfoParts = uri.getUserInfo().split(":", 2);
}
}
public String[] getUserInfoParts() {
return mUserInfoParts;
}
public String getHost() {
return mHost;
}
public int getPort() {
return mPort;
}
public void setSecurity(int connectionSecurity, boolean trustAllCertificates) {
mConnectionSecurity = connectionSecurity;
mTrustCertificates = trustAllCertificates;
}
public int getSecurity() {
return mConnectionSecurity;
}
public boolean canTrySslSecurity() {
return mConnectionSecurity == CONNECTION_SECURITY_SSL;
}
public boolean canTryTlsSecurity() {
return mConnectionSecurity == Transport.CONNECTION_SECURITY_TLS;
}
public boolean canTrustAllCertificates() {
return mTrustCertificates;
}
/**
* Attempts to open a connection using the Uri supplied for connection parameters. Will attempt
* an SSL connection if indicated.
*/
public void open() throws MessagingException, CertificateValidationException {
if (Config.LOGD && Email.DEBUG) {
Log.d(Email.LOG_TAG, "*** " + mDebugLabel + " open " +
getHost() + ":" + String.valueOf(getPort()));
}
try {
SocketAddress socketAddress = new InetSocketAddress(getHost(), getPort());
if (canTrySslSecurity()) {
mSocket = SSLUtils.getSSLSocketFactory(canTrustAllCertificates()).createSocket();
} else {
mSocket = new Socket();
}
mSocket.connect(socketAddress, SOCKET_CONNECT_TIMEOUT);
mIn = new BufferedInputStream(mSocket.getInputStream(), 1024);
mOut = new BufferedOutputStream(mSocket.getOutputStream(), 512);
} catch (SSLException e) {
if (Config.LOGD && Email.DEBUG) {
Log.d(Email.LOG_TAG, e.toString());
}
throw new CertificateValidationException(e.getMessage(), e);
} catch (IOException ioe) {
if (Config.LOGD && Email.DEBUG) {
Log.d(Email.LOG_TAG, ioe.toString());
}
throw new MessagingException(MessagingException.IOERROR, ioe.toString());
}
}
/**
* Attempts to reopen a TLS connection using the Uri supplied for connection parameters.
*
* TODO should we explicitly close the old socket? This seems funky to abandon it.
*/
public void reopenTls() throws MessagingException {
try {
mSocket = SSLUtils.getSSLSocketFactory(canTrustAllCertificates())
.createSocket(mSocket, getHost(), getPort(), true);
mSocket.setSoTimeout(SOCKET_READ_TIMEOUT);
mIn = new BufferedInputStream(mSocket.getInputStream(), 1024);
mOut = new BufferedOutputStream(mSocket.getOutputStream(), 512);
} catch (SSLException e) {
if (Config.LOGD && Email.DEBUG) {
Log.d(Email.LOG_TAG, e.toString());
}
throw new CertificateValidationException(e.getMessage(), e);
} catch (IOException ioe) {
if (Config.LOGD && Email.DEBUG) {
Log.d(Email.LOG_TAG, ioe.toString());
}
throw new MessagingException(MessagingException.IOERROR, ioe.toString());
}
}
/**
* Set the socket timeout.
* @param timeoutMilliseconds the read timeout value if greater than {@code 0}, or
* {@code 0} for an infinite timeout.
*/
public void setSoTimeout(int timeoutMilliseconds) throws SocketException {
mSocket.setSoTimeout(timeoutMilliseconds);
}
public boolean isOpen() {
return (mIn != null && mOut != null &&
mSocket != null && mSocket.isConnected() && !mSocket.isClosed());
}
/**
* Close the connection. MUST NOT return any exceptions - must be "best effort" and safe.
*/
public void close() {
try {
mIn.close();
} catch (Exception e) {
// May fail if the connection is already closed.
}
try {
mOut.close();
} catch (Exception e) {
// May fail if the connection is already closed.
}
try {
mSocket.close();
} catch (Exception e) {
// May fail if the connection is already closed.
}
mIn = null;
mOut = null;
mSocket = null;
}
public InputStream getInputStream() {
return mIn;
}
public OutputStream getOutputStream() {
return mOut;
}
/**
* Writes a single line to the server using \r\n termination.
*/
public void writeLine(String s, String sensitiveReplacement) throws IOException {
if (Config.LOGD && Email.DEBUG) {
if (sensitiveReplacement != null && !Email.DEBUG_SENSITIVE) {
Log.d(Email.LOG_TAG, ">>> " + sensitiveReplacement);
} else {
Log.d(Email.LOG_TAG, ">>> " + s);
}
}
OutputStream out = getOutputStream();
out.write(s.getBytes());
out.write('\r');
out.write('\n');
out.flush();
}
/**
* Reads a single line from the server, using either \r\n or \n as the delimiter. The
* delimiter char(s) are not included in the result.
*/
public String readLine() throws IOException {
StringBuffer sb = new StringBuffer();
InputStream in = getInputStream();
int d;
while ((d = in.read()) != -1) {
if (((char)d) == '\r') {
continue;
} else if (((char)d) == '\n') {
break;
} else {
sb.append((char)d);
}
}
if (d == -1 && Config.LOGD && Email.DEBUG) {
Log.d(Email.LOG_TAG, "End of stream reached while trying to read line.");
}
String ret = sb.toString();
if (Config.LOGD) {
if (Email.DEBUG) {
Log.d(Email.LOG_TAG, "<<< " + ret);
}
}
return ret;
}
}