org.syncany.plugins.webdav.WebdavTransferManager.java Source code

Java tutorial

Introduction

Here is the source code for org.syncany.plugins.webdav.WebdavTransferManager.java

Source

/*
 * Syncany, www.syncany.org
 * Copyright (C) 2011-2014 Philipp C. Heckel <philipp.heckel@gmail.com> 
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.syncany.plugins.webdav;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URI;
import java.security.KeyStoreException;
import java.security.MessageDigest;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;

import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLPeerUnverifiedException;

import org.apache.commons.io.IOUtils;
import org.apache.http.conn.socket.ConnectionSocketFactory;
import org.apache.http.conn.ssl.AllowAllHostnameVerifier;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.conn.ssl.SSLContexts;
import org.apache.http.conn.ssl.TrustStrategy;
import org.syncany.config.Config;
import org.syncany.config.UserConfig;
import org.syncany.crypto.CipherUtil;
import org.syncany.plugins.UserInteractionListener;
import org.syncany.plugins.transfer.AbstractTransferManager;
import org.syncany.plugins.transfer.StorageException;
import org.syncany.plugins.transfer.StorageMoveException;
import org.syncany.plugins.transfer.files.ActionRemoteFile;
import org.syncany.plugins.transfer.files.CleanupRemoteFile;
import org.syncany.plugins.transfer.files.DatabaseRemoteFile;
import org.syncany.plugins.transfer.files.MultichunkRemoteFile;
import org.syncany.plugins.transfer.files.RemoteFile;
import org.syncany.plugins.transfer.files.SyncanyRemoteFile;
import org.syncany.plugins.transfer.files.TempRemoteFile;
import org.syncany.plugins.transfer.files.TransactionRemoteFile;
import org.syncany.util.StringUtil;

import com.github.sardine.DavResource;
import com.github.sardine.Sardine;
import com.github.sardine.SardineFactory;
import com.github.sardine.impl.SardineException;
import com.github.sardine.impl.SardineImpl;

public class WebdavTransferManager extends AbstractTransferManager {
    private static final Logger logger = Logger.getLogger(WebdavTransferManager.class.getSimpleName());

    private static final String APPLICATION_CONTENT_TYPE = "application/octet-stream";
    private static final int HTTP_NOT_FOUND = 404;

    private static boolean hasNewCertificates;

    private Sardine sardine;

    private String repoPath;
    private String multichunksPath;
    private String databasesPath;
    private String actionsPath;
    private String transactionsPath;
    private String tempPath;

    public WebdavTransferManager(WebdavTransferSettings connection, Config config) {
        super(connection, config);

        this.sardine = null;

        this.repoPath = connection.getUrl().replaceAll("/$", "") + "/";
        this.multichunksPath = repoPath + "multichunks/";
        this.databasesPath = repoPath + "databases/";
        this.actionsPath = repoPath + "actions/";
        this.transactionsPath = repoPath + "transactions/";
        this.tempPath = repoPath + "temporary/";
    }

    public WebdavTransferSettings getSettings() {
        return (WebdavTransferSettings) settings;
    }

    @Override
    public void connect() throws StorageException {
        if (sardine == null) {
            if (getSettings().isSecure()) {
                logger.log(Level.INFO, "WebDAV: Connect called. Creating Sardine (SSL!) ...");

                try {
                    final ConnectionSocketFactory sslSocketFactory = initSsl();

                    sardine = new SardineImpl() {
                        @Override
                        protected ConnectionSocketFactory createDefaultSecureSocketFactory() {
                            return sslSocketFactory;
                        }
                    };

                    sardine.setCredentials(getSettings().getUsername(), getSettings().getPassword());
                } catch (Exception e) {
                    throw new StorageException(e);
                }
            } else {
                logger.log(Level.INFO, "WebDAV: Connect called. Creating Sardine (non-SSL) ...");
                sardine = SardineFactory.begin(getSettings().getUsername(), getSettings().getPassword());
            }
        }
    }

    @Override
    public void disconnect() {
        storeTrustStore();
        sardine = null;
    }

    @Override
    public void init(boolean createIfRequired) throws StorageException {
        connect();

        try {
            logger.log(Level.INFO, "WebDAV: Init called; creating repo directories ... ");

            if (!testTargetExists() && createIfRequired) {
                sardine.createDirectory(repoPath);
            }

            sardine.createDirectory(multichunksPath);
            sardine.createDirectory(databasesPath);
            sardine.createDirectory(actionsPath);
            sardine.createDirectory(transactionsPath);
            sardine.createDirectory(tempPath);
        } catch (Exception e) {
            logger.log(Level.SEVERE, "Cannot initialize WebDAV folder.", e);
            throw new StorageException(e);
        }
    }

    @Override
    public void download(RemoteFile remoteFile, File localFile) throws StorageException {
        connect();
        String remoteURL = getRemoteFileUrl(remoteFile);

        try {
            logger.log(Level.INFO, "WebDAV: Downloading " + remoteURL + " to temp file " + localFile + " ...");

            InputStream webdavFileInputStream = sardine.get(remoteURL);
            FileOutputStream localFileOutputStream = new FileOutputStream(localFile);

            IOUtils.copy(webdavFileInputStream, localFileOutputStream);

            localFileOutputStream.close();
            webdavFileInputStream.close();
        } catch (IOException ex) {
            logger.log(Level.SEVERE, "Error while downloading file from WebDAV: " + remoteURL, ex);
            throw new StorageException(ex);
        }
    }

    @Override
    public void upload(File localFile, RemoteFile remoteFile) throws StorageException {
        connect();
        String remoteURL = getRemoteFileUrl(remoteFile);

        try {
            logger.log(Level.INFO, "WebDAV: Uploading local file " + localFile + " to " + remoteURL + " ...");

            InputStream localFileInputStream = new FileInputStream(localFile);
            sardine.put(remoteURL, localFileInputStream, APPLICATION_CONTENT_TYPE, true, localFile.length());

            localFileInputStream.close();
        } catch (Exception ex) {
            logger.log(Level.SEVERE, "Error while uploading file to WebDAV: " + remoteURL, ex);
            throw new StorageException(ex);
        }
    }

    @Override
    public <T extends RemoteFile> Map<String, T> list(Class<T> remoteFileClass) throws StorageException {
        connect();

        try {
            // List folder
            String remoteFileUrl = getRemoteFilePath(remoteFileClass);
            logger.log(Level.INFO, "WebDAV: Listing objects in " + remoteFileUrl + " ...");

            List<DavResource> resources = sardine.list(remoteFileUrl);

            // Create RemoteFile objects
            String rootPath = repoPath.substring(0, repoPath.length() - new URI(repoPath).getRawPath().length());
            Map<String, T> remoteFiles = new HashMap<String, T>();

            for (DavResource res : resources) {
                // WebDAV returns the parent resource itself; ignore it
                String fullResourceUrl = rootPath + res.getPath().replaceAll("/$", "") + "/";
                boolean isParentResource = remoteFileUrl.equals(fullResourceUrl.toString());

                if (!isParentResource) {
                    try {
                        T remoteFile = RemoteFile.createRemoteFile(res.getName(), remoteFileClass);
                        remoteFiles.put(res.getName(), remoteFile);

                        logger.log(Level.FINE, "WebDAV: Matching WebDAV resource: " + res);
                    } catch (Exception e) {
                        logger.log(Level.FINEST,
                                "Cannot create instance of " + remoteFileClass.getSimpleName() + " for object "
                                        + res.getName() + "; maybe invalid file name pattern. Ignoring file.");
                    }
                }
            }

            return remoteFiles;
        } catch (Exception ex) {
            logger.log(Level.SEVERE, "WebDAV: Unable to list WebDAV directory.", ex);
            throw new StorageException(ex);
        }
    }

    @Override
    public boolean delete(RemoteFile remoteFile) throws StorageException {
        connect();
        String remoteURL = getRemoteFileUrl(remoteFile);

        try {
            logger.log(Level.FINE, "WebDAV: Deleting " + remoteURL);
            sardine.delete(remoteURL);

            return true;
        } catch (SardineException e) {
            if (e.getStatusCode() == HTTP_NOT_FOUND) {
                return true;
            } else {
                return false;
            }
        } catch (IOException ex) {
            logger.log(Level.SEVERE, "Error while deleting file from WebDAV: " + remoteURL, ex);
            throw new StorageException(ex);
        }
    }

    @Override
    public void move(RemoteFile sourceFile, RemoteFile targetFile) throws StorageException {
        connect();

        String sourceURL = getRemoteFileUrl(sourceFile);
        String targetURL = getRemoteFileUrl(targetFile);

        try {
            sardine.move(sourceURL, targetURL);
        } catch (IOException e) {
            throw new StorageMoveException("Unable to move " + sourceURL + " to " + targetURL, e);
        }
    }

    private String getRemoteFileUrl(RemoteFile remoteFile) {
        return getRemoteFilePath(remoteFile.getClass()) + remoteFile.getName();
    }

    private String getRemoteFilePath(Class<? extends RemoteFile> remoteFile) {
        if (remoteFile.equals(MultichunkRemoteFile.class)) {
            return multichunksPath;
        } else if (remoteFile.equals(DatabaseRemoteFile.class) || remoteFile.equals(CleanupRemoteFile.class)) {
            return databasesPath;
        } else if (remoteFile.equals(ActionRemoteFile.class)) {
            return actionsPath;
        } else if (remoteFile.equals(TransactionRemoteFile.class)) {
            return transactionsPath;
        } else if (remoteFile.equals(TempRemoteFile.class)) {
            return tempPath;
        } else {
            return repoPath;
        }
    }

    @Override
    public boolean testTargetCanWrite() throws StorageException {
        try {
            String testFileUrl = repoPath + "syncany-write-test";

            sardine.put(testFileUrl, new byte[] { 0x01 });
            sardine.delete(testFileUrl);

            logger.log(Level.INFO, "testTargetCanWrite: Can write, test file created/deleted successfully.");
            return true;
        } catch (SSLPeerUnverifiedException e) {
            logger.log(Level.SEVERE, "testTargetCanWrite: SSL handshake failed; peer not authenticated.", e);
            throw new StorageException("SSL handshake failed; peer not authenticated.", e);
        } catch (Exception e) {
            logger.log(Level.INFO, "testTargetCanWrite: Can NOT write to target.", e);
            return false;
        }
    }

    /**
     * Checks if the repo exists at the repo URL.
     * 
     * <p><b>Note:</b> This uses list() instead of exists() because Sardine implements
     * the exists() method with a HTTP HEAD only. Some WebDAV servers respond with "Forbidden" 
     * if for directories.
     */
    @Override
    public boolean testTargetExists() throws StorageException {
        try {
            sardine.list(repoPath);

            logger.log(Level.INFO, "testTargetExists: Target exists.");
            return true;
        } catch (SSLPeerUnverifiedException e) {
            logger.log(Level.SEVERE, "testTargetCanWrite: SSL handshake failed; peer not authenticated.", e);
            throw new StorageException("SSL handshake failed; peer not authenticated.", e);
        } catch (Exception e) {
            logger.log(Level.WARNING, "testTargetExists: Exception thrown while testing if folder exists.", e);
            return false;
        }
    }

    @Override
    public boolean testTargetCanCreate() throws StorageException {
        try {
            if (testTargetExists()) {
                logger.log(Level.INFO,
                        "testTargetCanCreate: Target already exists, so 'can create' test successful.");
                return true;
            } else {
                sardine.createDirectory(repoPath);
                sardine.delete(repoPath);

                logger.log(Level.INFO, "testTargetCanCreate: Target can be created (test-created successfully).");
                return true;
            }
        } catch (SSLPeerUnverifiedException e) {
            logger.log(Level.SEVERE, "testTargetCanWrite: SSL handshake failed; peer not authenticated.", e);
            throw new StorageException("SSL handshake failed; peer not authenticated.", e);
        } catch (Exception e) {
            logger.log(Level.INFO, "testTargetCanCreate: Target can NOT be created.", e);
            return false;
        }
    }

    @Override
    public boolean testRepoFileExists() throws StorageException {
        try {
            String repoFileUrl = getRemoteFileUrl(new SyncanyRemoteFile());

            if (sardine.exists(repoFileUrl)) {
                logger.log(Level.INFO, "testRepoFileExists: Repo file exists.");
                return true;
            } else {
                logger.log(Level.INFO, "testRepoFileExists: Repo file does NOT exist.");
                return false;
            }
        } catch (SSLPeerUnverifiedException e) {
            logger.log(Level.SEVERE, "testTargetCanWrite: SSL handshake failed; peer not authenticated.", e);
            throw new StorageException("SSL handshake failed; peer not authenticated.", e);
        } catch (Exception e) {
            logger.log(Level.WARNING, "testRepoFileExists: Exception thrown while testing if repo file exists.", e);
            return false;
        }
    }

    private void storeTrustStore() {
        if (!hasNewCertificates) {
            logger.log(Level.INFO, "WebDAV: No new certificates. Nothing to store.");
        } else {
            logger.log(Level.INFO, "WebDAV: New certificates. Storing trust store on disk.");

            UserConfig.storeTrustStore();
            hasNewCertificates = false;
        }
    }

    private ConnectionSocketFactory initSsl() throws Exception {
        TrustStrategy trustStrategy = new TrustStrategy() {
            @Override
            public boolean isTrusted(X509Certificate[] certificateChain, String authType)
                    throws CertificateException {
                logger.log(Level.INFO, "WebDAV: isTrusted(" + certificateChain.toString() + ", " + authType + ")");

                try {
                    // First check if already in trust store, if so; okay!
                    X509Certificate serverCertificate = certificateChain[0];

                    for (int i = 0; i < certificateChain.length; i++) {
                        X509Certificate certificate = certificateChain[i];

                        logger.log(Level.FINE,
                                "WebDAV: Checking certificate validity: " + certificate.getSubjectDN().toString());
                        logger.log(Level.FINEST, "WebDAV:              Full certificate: " + certificate);

                        // Check validity
                        try {
                            certificate.checkValidity();
                        } catch (CertificateException e) {
                            logger.log(Level.FINE, "WebDAV: Certificate is NOT valid.", e);
                            return false;
                        }

                        logger.log(Level.FINE, "WebDAV: Checking is VALID.");

                        // Certificate found; we trust this, okay!
                        if (inTrustStore(certificate)) {
                            logger.log(Level.FINE, "WebDAV: Certificate found in trust store.");
                            return true;
                        }

                        // Certificate is new; continue ...
                        else {
                            logger.log(Level.FINE, "WebDAV: Certificate NOT found in trust store.");
                        }
                    }

                    // We we reach this code, none of the CAs are known in the trust store
                    // So we ask the user if he/she wants to add the server certificate to the trust store  
                    UserInteractionListener userInteractionListener = getSettings().getUserInteractionListener();

                    if (userInteractionListener == null) {
                        throw new RuntimeException("pluginListener cannot be null!");
                    }

                    boolean userTrustsCertificate = userInteractionListener.onUserConfirm(
                            "Unknown SSL/TLS certificate", formatCertificate(serverCertificate),
                            "Do you want to trust this certificate?");

                    if (!userTrustsCertificate) {
                        logger.log(Level.INFO, "WebDAV: User does not trust certificate. ABORTING.");
                        throw new RuntimeException("User does not trust certificate. ABORTING.");
                    }

                    logger.log(Level.INFO, "WebDAV: User trusts certificate. Adding to trust store.");
                    addToTrustStore(serverCertificate);

                    return true;
                } catch (KeyStoreException e) {
                    logger.log(Level.SEVERE, "WebDAV: Key store exception.", e);
                    return false;
                }
            }

            private boolean inTrustStore(X509Certificate certificate) throws KeyStoreException {
                String certAlias = getCertificateAlias(certificate);
                return UserConfig.getUserTrustStore().containsAlias(certAlias);
            }

            private void addToTrustStore(X509Certificate certificate) throws KeyStoreException {
                String certAlias = getCertificateAlias(certificate);
                UserConfig.getUserTrustStore().setCertificateEntry(certAlias, certificate);

                hasNewCertificates = true;
            }

            private String getCertificateAlias(X509Certificate certificate) {
                return StringUtil.toHex(certificate.getSignature());
            }
        };

        SSLContext sslContext = SSLContexts.custom().loadTrustMaterial(null, trustStrategy).useTLS().build();

        return new SSLConnectionSocketFactory(sslContext, new AllowAllHostnameVerifier());
    }

    private String formatCertificate(X509Certificate cert) {
        try {
            CipherUtil.enableUnlimitedStrength(); // Dirty!

            String checksumMd5 = formatChecksum(createChecksum(cert.getEncoded(), "MD5"));
            String checksumSha1 = formatChecksum(createChecksum(cert.getEncoded(), "SHA1"));
            String checksumSha256 = formatChecksum(createChecksum(cert.getEncoded(), "SHA256"));

            StringBuilder sb = new StringBuilder();

            sb.append(String.format("Owner: %s\n", cert.getSubjectDN().getName()));
            sb.append(String.format("Issuer: %s\n", cert.getIssuerDN().getName()));
            sb.append(String.format("Serial number: %d\n", cert.getSerialNumber()));
            sb.append(String.format("Valid from %s until: %s\n", cert.getNotBefore().toString(),
                    cert.getNotAfter().toString()));
            sb.append("Certificate fingerprints:\n");
            sb.append(String.format(" MD5:  %s\n", checksumMd5));
            sb.append(String.format(" SHA1: %s\n", checksumSha1));
            sb.append(String.format(" SHA256: %s", checksumSha256));

            return sb.toString();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    private String formatChecksum(byte[] checksum) {
        StringBuilder sb = new StringBuilder();

        for (int i = 0; i < checksum.length; i++) {
            sb.append(StringUtil.toHex(new byte[] { checksum[i] }).toUpperCase());

            if (i < checksum.length - 1) {
                sb.append(":");
            }
        }

        return sb.toString();
    }

    private byte[] createChecksum(byte[] data, String digestAlgorithm) {
        try {
            MessageDigest digest = MessageDigest.getInstance(digestAlgorithm);
            digest.update(data, 0, data.length);

            return digest.digest();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}