Java tutorial
/* * * Panbox - encryption for cloud storage * Copyright (C) 2014-2015 by Fraunhofer SIT and Sirrix AG * * 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/>. * * Additonally, third party code may be provided with notices and open source * licenses from communities and third parties that govern the use of those * portions, and any licenses granted hereunder do not alter any rights and * obligations you may have under such open source licenses, however, the * disclaimer of warranty and limitation of liability provisions of the GPLv3 * will apply to all the product. * */ package org.panbox.desktop.common.vfs.backend.generic; import java.io.File; import java.io.IOException; import java.nio.ByteBuffer; import java.nio.file.Files; import java.nio.file.LinkOption; import java.nio.file.attribute.BasicFileAttributes; import java.nio.file.attribute.FileTime; import java.util.Hashtable; import javax.crypto.SecretKey; import org.apache.commons.io.FileUtils; import org.apache.log4j.Logger; import org.panbox.core.crypto.io.AESGCMRandomAccessFileCompat; import org.panbox.core.exception.FileEncryptionException; import org.panbox.core.exception.FileIntegrityException; import org.panbox.core.vfs.backend.VirtualFile; import org.panbox.core.vfs.backend.VirtualVolume; import org.panbox.desktop.common.ex.PanboxEncryptionException; import org.panbox.desktop.common.ex.PanboxIntegrityException; import org.panbox.desktop.common.vfs.backend.VirtualRandomAccessFile; public class GenericVirtualFileImpl extends VirtualRandomAccessFile { protected File file; protected AESGCMRandomAccessFileCompat aesRandomAccessFile; protected boolean deleteFileOnClose = false; private final static Logger logger = Logger.getLogger(GenericVirtualFileImpl.class); /** * stores number of open file handles for each opened file */ final static Hashtable<AESGCMRandomAccessFileCompat, Integer> filehandleCtrMap = new Hashtable<AESGCMRandomAccessFileCompat, Integer>(); protected GenericVirtualFileImpl(String fileName, VirtualVolume volume) { super(fileName, volume); file = new File(fileName); try { if (!isDirectory()) { if (exists()) { aesRandomAccessFile = file.canWrite() ? AESGCMRandomAccessFileCompat.getInstance(file, true) : AESGCMRandomAccessFileCompat.getInstance(file, false); // System.err.println("getInstance(" + file.getName() + "," // + aesRandomAccessFile.writable + ") -> " // + aesRandomAccessFile.toString()); } else { aesRandomAccessFile = file.getParentFile().canWrite() ? AESGCMRandomAccessFileCompat.getInstance(file, true) : AESGCMRandomAccessFileCompat.getInstance(file, false); // System.err.println("getInstance(" + file.getName() + "," // + aesRandomAccessFile.writable + ") -> " // + aesRandomAccessFile.toString()); } } } catch (IOException | FileEncryptionException e) { logger.error("Unable to initialize AES backend", e); } } @Override public boolean isDirectory() { return file.isDirectory(); } @Override public boolean delete() { if (file.isDirectory()) { try { FileUtils.deleteDirectory(file); return true; } catch (IOException e) { e.printStackTrace(); return false; } } else { return file.delete(); } } @Override public boolean createNewDirectory() { return file.mkdirs(); } @Override public boolean exists() { return file.exists(); } @Override public long length() throws IOException { // return aesRandomAccessFile.length(); return AESGCMRandomAccessFileCompat.realToVirtualFileSize(file.length()); } @Override public VirtualFile[] list() { String[] files = file.list(); GenericVirtualFileImpl[] fileList = new GenericVirtualFileImpl[files.length]; for (int i = 0; i < files.length; ++i) { fileList[i] = new GenericVirtualFileImpl(new File(file, files[i]).getPath(), volume); } return fileList; } @Override public String getPath() { return file.getPath(); } @Override public String getRelativePath() { return volume.getRelativePathForFile(this); } @Override public boolean renameTo(VirtualFile newFile) { if (isDirectory()) { return file.renameTo(newFile.getFile()); } else { // use backend rename function GenericVirtualFileImpl newDFile = (GenericVirtualFileImpl) newFile; if (aesRandomAccessFile.renameTo(newDFile.getFile())) { this.file = newDFile.getFile(); return true; } else { return false; } } } @Override public File getFile() { return file; } @Override public String toString() { return file.getName() + " at " + file.getAbsoluteFile(); } @Override public long getCreationTime() { try { BasicFileAttributes attr = Files.readAttributes(file.toPath(), BasicFileAttributes.class, LinkOption.NOFOLLOW_LINKS); return attr.creationTime().toMillis(); } catch (IOException e) { logger.error("Error in getCreationTime()", e); return 0; } } @Override public long getLastAccessTime() { try { BasicFileAttributes attr = Files.readAttributes(file.toPath(), BasicFileAttributes.class, LinkOption.NOFOLLOW_LINKS); return attr.lastAccessTime().toMillis(); } catch (IOException e) { logger.error("Error in getLastAccessTime()", e); return 0; } } @Override public long getLastWriteTime() { // return file.lastModified(); try { BasicFileAttributes attr = Files.readAttributes(file.toPath(), BasicFileAttributes.class, LinkOption.NOFOLLOW_LINKS); return attr.lastModifiedTime().toMillis(); } catch (IOException e) { logger.error("Error in getLastWriteTime()", e); return 0; } } @Override public void setLastAccessTime(long atime) throws IOException { if (atime > 0) { FileTime fileTime = FileTime.fromMillis(atime); Files.setAttribute(file.toPath(), "lastAccessTime", fileTime); } } @Override public void setModifiedTime(long mtime) throws IOException { if (mtime > 0) { FileTime fileTime = FileTime.fromMillis(mtime); Files.setLastModifiedTime(file.toPath(), fileTime); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#seek(long) */ @Override public void seek(long pos) throws IOException, PanboxEncryptionException { try { aesRandomAccessFile.seek(pos); } catch (IOException e) { throw new IOException(e.getMessage(), e); } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#getFilePointer() */ @Override public long getFilePointer() throws IOException { try { return aesRandomAccessFile.getFilePointer(); } catch (IOException e) { throw new IOException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#skipBytes(int) */ @Override public int skipBytes(int n) throws IOException, PanboxEncryptionException { try { return aesRandomAccessFile.skipBytes(n); } catch (IOException e) { throw new IOException(e.getMessage(), e); } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#write(byte[]) */ @Override public void write(byte[] b) throws IOException, PanboxEncryptionException { try { aesRandomAccessFile.write(b); } catch (IOException e) { throw new IOException(e.getMessage(), e); } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } catch (FileIntegrityException e) { throw new PanboxIntegrityException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#write(long, * java.nio.ByteBuffer) */ @Override public int write(long seekpos, ByteBuffer b) throws IOException, PanboxEncryptionException { try { aesRandomAccessFile.seek(seekpos); byte[] buf; if (b.hasArray()) { buf = b.array(); this.write(buf, 0, buf.length); } else { buf = new byte[b.remaining()]; b.get(buf); this.write(buf, 0, buf.length); } return buf.length; } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#write(long, * java.nio.ByteBuffer) */ @Override public int write(long seekpos, byte[] b) throws IOException, PanboxEncryptionException { try { aesRandomAccessFile.seek(seekpos); this.write(b, 0, b.length); return b.length; } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#write(byte[], int, * int) */ @Override public void write(byte[] b, int off, int len) throws IOException, PanboxEncryptionException { try { aesRandomAccessFile.write(b, off, len); } catch (IOException e) { throw new IOException(e.getMessage(), e); } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } catch (FileIntegrityException e) { throw new PanboxIntegrityException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#write(int) */ @Override public void write(int b) throws IOException, PanboxEncryptionException { try { aesRandomAccessFile.write(b); } catch (IOException e) { throw new IOException(e.getMessage(), e); } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } catch (FileIntegrityException e) { throw new PanboxIntegrityException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#read(byte[], int, * int) */ @Override public int read(byte[] b, int off, int len) throws IOException, PanboxEncryptionException { try { return aesRandomAccessFile.read(b, off, len); } catch (IOException e) { throw new IOException(e.getMessage(), e); } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } catch (FileIntegrityException e) { throw new PanboxIntegrityException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#read(byte[]) */ @Override public int read(byte[] b) throws IOException, PanboxEncryptionException { try { return aesRandomAccessFile.read(b); } catch (IOException e) { throw new IOException(e.getMessage(), e); } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } catch (FileIntegrityException e) { throw new PanboxIntegrityException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#read(long, * java.nio.ByteBuffer) */ @Override public int read(long seekpos, ByteBuffer b) throws IOException, PanboxEncryptionException { byte[] buf = new byte[b.remaining()]; // raf.array() does not // work, because backend // byte[] is missing! try { aesRandomAccessFile.seek(seekpos); int reallyRead = aesRandomAccessFile.read(buf, 0, buf.length); if (reallyRead != -1) { // Trim NUL-Bytes from file b.put(buf, 0, reallyRead); return reallyRead; } else { // EOF is indicated by -1; returning -1 will be misinterpreted // as an ERRNO (i.e. EPERM) return 0; } } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } catch (FileIntegrityException e) { throw new PanboxIntegrityException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#read(long, * java.nio.ByteBuffer) */ @Override public int read(long seekpos, byte[] b) throws IOException, PanboxEncryptionException { try { aesRandomAccessFile.seek(seekpos); int reallyRead = aesRandomAccessFile.read(b); if (reallyRead == -1) { // EOF is indicated by -1; returning -1 will be misinterpreted // as an ERRNO (i.e. EPERM) return 0; } else { return reallyRead; } } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } catch (FileIntegrityException e) { throw new PanboxIntegrityException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#read() */ @Override public int read() throws IOException, PanboxEncryptionException { try { return aesRandomAccessFile.read(); } catch (IOException e) { throw new IOException(e.getMessage(), e); } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } catch (FileIntegrityException e) { throw new PanboxIntegrityException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#open(java.io.File, * boolean) */ @Override public void open() throws IOException, PanboxEncryptionException { try { // windows verifies file existance by calling create(OPEN_EXISTING) // - thus check if file exists at an earlypoint in time if (!file.exists()) { throw new IOException("File " + file + "does not exist!"); } else { // TODO: support read-only mode, use fileinfo-objects // check file handle counter maps and create/increase values synchronized (filehandleCtrMap) { Integer fhctr = filehandleCtrMap.get(aesRandomAccessFile); // System.err.println("open(" + file.getName() + "," // + aesRandomAccessFile.writable + ", ctr=" + fhctr // + ") -> " + aesRandomAccessFile.toString()); if (fhctr != null) { // file has already been opened - only increase counter filehandleCtrMap.put(aesRandomAccessFile, ++fhctr); } else { aesRandomAccessFile.open(); filehandleCtrMap.put(aesRandomAccessFile, 1); } } } } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#create(int, * javax.crypto.SecretKey, java.io.File) */ @Override public void create(int shareKeyVersion, SecretKey shareKey) throws IOException, PanboxEncryptionException { try { // don't check if file has been opened - multiple create() calls on // the same file should cause an exception // TODO: check error handling + mapping to error codes aesRandomAccessFile.create(shareKeyVersion, shareKey); // System.err.println("create(" + file.getName() + "," // + aesRandomAccessFile.writable + ") -> " // + aesRandomAccessFile.toString()); // check file handle counter maps and create/increase values synchronized (filehandleCtrMap) { Integer fhctr = filehandleCtrMap.get(aesRandomAccessFile); if (fhctr == null) { filehandleCtrMap.put(aesRandomAccessFile, 1); } } } catch (IOException e) { throw new IOException(e.getMessage(), e); } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#flush() */ @Override public void flush() throws IOException { aesRandomAccessFile.flush(); } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#close() */ @Override public void close() throws IOException { if (!file.exists()) { throw new IOException("File " + file + "does not exist!"); } else { synchronized (filehandleCtrMap) { Integer fhctr = filehandleCtrMap.get(aesRandomAccessFile); if ((fhctr == null) || (fhctr < 1)) { throw new IOException("Invalid value of file handle counter!"); } else { if (fhctr == 1) { // last reference, close file and remove entry aesRandomAccessFile.close(); // System.err.println("close(" + file.getName() + "," // + aesRandomAccessFile.writable + ") -> " // + aesRandomAccessFile.toString()); filehandleCtrMap.remove(aesRandomAccessFile); if (deleteFileOnClose) { delete(); } } else if (fhctr > 1) { // decrease counter value, but don't close file filehandleCtrMap.put(aesRandomAccessFile, --fhctr); } } } } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#setDeleteOnClose() */ @Override public void setDeleteOnClose() { deleteFileOnClose = true; } /* * (non-Javadoc) * * @see * org.panbox.desktop.common.vfs.backend.VirtualFile#getShareKeyVersion() */ @Override public int getShareKeyVersion() throws PanboxEncryptionException, IOException { try { return aesRandomAccessFile.getShareKeyVersion(); } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see * org.panbox.desktop.common.vfs.backend.VirtualFile#initWithShareKey(javax * .crypto .SecretKey) */ @Override public void initWithShareKey(SecretKey shareKey) throws PanboxEncryptionException, IOException { try { aesRandomAccessFile.initWithShareKey(shareKey); } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } catch (FileIntegrityException e) { throw new PanboxIntegrityException(e.getMessage(), e); } } /* * (non-Javadoc) * * @see org.panbox.desktop.common.vfs.backend.VirtualFile#setLength(long) */ @Override public void setLength(long newLength) throws IOException, PanboxEncryptionException { try { aesRandomAccessFile.setLength(newLength); } catch (FileEncryptionException e) { throw new PanboxEncryptionException(e.getMessage(), e); } catch (FileIntegrityException e) { throw new PanboxIntegrityException(e.getMessage(), e); } } @Override public boolean isOpened() { return aesRandomAccessFile.isOpen(); } @Override public boolean isSymbolic() { return Files.isSymbolicLink(getFile().toPath()); } @Override public void setAttr(long attr) throws IOException { super.setAttr(attr); } @Override public boolean canExecute() { return file.canExecute(); } @Override public boolean canRead() { return file.canRead(); } @Override public boolean canWrite() { return file.canWrite(); } }