/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.ivy.plugins.repository.ssh;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelExec;
import com.jcraft.jsch.JSchException;
import com.jcraft.jsch.Session;
/**
* This class is using the scp client to transfer data and information for the repository.
* <p>
* It is based on the SCPClient from the ganymed ssh library from Christian Plattner, released under
* a BSD style license.
* <p>
* To minimize the dependency to the ssh library and because we needed some additional
* functionality, we decided to copy'n'paste the single class rather than to inherit or delegate it
* somehow.
* <p>
* Nevertheless credit should go to the original author.
*/
public class Scp {
private static final int MODE_LENGTH = 4;
private static final int SEND_FILE_BUFFER_LENGTH = 40000;
private static final int SEND_BYTES_BUFFER_LENGTH = 512;
private static final int MIN_TLINE_LENGTH = 8;
private static final int CLINE_SPACE_INDEX2 = 5;
private static final int CLINE_SPACE_INDEX1 = 4;
private static final int MIN_C_LINE_LENGTH = 8;
private static final int DEFAULT_LINE_BUFFER_LENGTH = 30;
private static final int BUFFER_SIZE = 64 * 1024;
/*
* Maximum length authorized for scp lines. This is a random limit - if your path names are
* longer, then adjust it.
*/
private static final int MAX_SCP_LINE_LENGTH = 8192;
private Session session;
public class FileInfo {
private String filename;
private long length;
private long lastModified;
/**
* @param filename
* The filename to set.
*/
public void setFilename(String filename) {
this.filename = filename;
}
/**
* @return Returns the filename.
*/
public String getFilename() {
return filename;
}
/**
* @param length
* The length to set.
*/
public void setLength(long length) {
this.length = length;
}
/**
* @return Returns the length.
*/
public long getLength() {
return length;
}
/**
* @param lastModified
* The lastModified to set.
*/
public void setLastModified(long lastModified) {
this.lastModified = lastModified;
}
/**
* @return Returns the lastModified.
*/
public long getLastModified() {
return lastModified;
}
}
public Scp(Session session) {
if (session == null) {
throw new IllegalArgumentException("Cannot accept null argument!");
}
this.session = session;
}
private void readResponse(InputStream is) throws IOException, RemoteScpException {
int c = is.read();
if (c == 0) {
return;
}
if (c == -1) {
throw new RemoteScpException("Remote scp terminated unexpectedly.");
}
if ((c != 1) && (c != 2)) {
throw new RemoteScpException("Remote scp sent illegal error code.");
}
if (c == 2) {
throw new RemoteScpException("Remote scp terminated with error.");
}
String err = receiveLine(is);
throw new RemoteScpException("Remote scp terminated with error (" + err + ").");
}
private String receiveLine(InputStream is) throws IOException, RemoteScpException {
StringBuffer sb = new StringBuffer(DEFAULT_LINE_BUFFER_LENGTH);
while (true) {
if (sb.length() > MAX_SCP_LINE_LENGTH) {
throw new RemoteScpException("Remote scp sent a too long line");
}
int c = is.read();
if (c < 0) {
throw new RemoteScpException("Remote scp terminated unexpectedly.");
}
if (c == '\n') {
break;
}
sb.append((char) c);
}
return sb.toString();
}
private void parseCLine(String line, FileInfo fileInfo) throws RemoteScpException {
/* Minimum line: "xxxx y z" ---> 8 chars */
long len;
if (line.length() < MIN_C_LINE_LENGTH) {
throw new RemoteScpException(
"Malformed C line sent by remote SCP binary, line too short.");
}
if ((line.charAt(CLINE_SPACE_INDEX1) != ' ') || (line.charAt(CLINE_SPACE_INDEX2) == ' ')) {
throw new RemoteScpException("Malformed C line sent by remote SCP binary.");
}
int lengthNameSep = line.indexOf(' ', CLINE_SPACE_INDEX2);
if (lengthNameSep == -1) {
throw new RemoteScpException("Malformed C line sent by remote SCP binary.");
}
String lengthSubstring = line.substring(CLINE_SPACE_INDEX2, lengthNameSep);
String nameSubstring = line.substring(lengthNameSep + 1);
if ((lengthSubstring.length() <= 0) || (nameSubstring.length() <= 0)) {
throw new RemoteScpException("Malformed C line sent by remote SCP binary.");
}
if ((CLINE_SPACE_INDEX2 + 1 + lengthSubstring.length() + nameSubstring.length()) != line
.length()) {
throw new RemoteScpException("Malformed C line sent by remote SCP binary.");
}
try {
len = Long.parseLong(lengthSubstring);
} catch (NumberFormatException e) {
throw new RemoteScpException(
"Malformed C line sent by remote SCP binary, cannot parse file length.");
}
if (len < 0) {
throw new RemoteScpException(
"Malformed C line sent by remote SCP binary, illegal file length.");
}
fileInfo.setLength(len);
fileInfo.setFilename(nameSubstring);
}
private void parseTLine(String line, FileInfo fileInfo) throws RemoteScpException {
/* Minimum line: "0 0 0 0" ---> 8 chars */
long modtime;
long firstMsec;
long atime;
long secondMsec;
if (line.length() < MIN_TLINE_LENGTH) {
throw new RemoteScpException(
"Malformed T line sent by remote SCP binary, line too short.");
}
int firstMsecBegin = line.indexOf(" ") + 1;
if (firstMsecBegin == 0 || firstMsecBegin >= line.length()) {
throw new RemoteScpException(
"Malformed T line sent by remote SCP binary, line not enough data.");
}
int atimeBegin = line.indexOf(" ", firstMsecBegin + 1) + 1;
if (atimeBegin == 0 || atimeBegin >= line.length()) {
throw new RemoteScpException(
"Malformed T line sent by remote SCP binary, line not enough data.");
}
int secondMsecBegin = line.indexOf(" ", atimeBegin + 1) + 1;
if (secondMsecBegin == 0 || secondMsecBegin >= line.length()) {
throw new RemoteScpException(
"Malformed T line sent by remote SCP binary, line not enough data.");
}
try {
modtime = Long.parseLong(line.substring(0, firstMsecBegin - 1));
firstMsec = Long.parseLong(line.substring(firstMsecBegin, atimeBegin - 1));
atime = Long.parseLong(line.substring(atimeBegin, secondMsecBegin - 1));
secondMsec = Long.parseLong(line.substring(secondMsecBegin));
} catch (NumberFormatException e) {
throw new RemoteScpException(
"Malformed C line sent by remote SCP binary, cannot parse file length.");
}
if (modtime < 0 || firstMsec < 0 || atime < 0 || secondMsec < 0) {
throw new RemoteScpException(
"Malformed C line sent by remote SCP binary, illegal file length.");
}
fileInfo.setLastModified(modtime);
}
private void sendFile(Channel channel, String localFile, String remoteName, String mode)
throws IOException, RemoteScpException {
byte[] buffer = new byte[BUFFER_SIZE];
OutputStream os = new BufferedOutputStream(channel.getOutputStream(),
SEND_FILE_BUFFER_LENGTH);
InputStream is = new BufferedInputStream(channel.getInputStream(), SEND_BYTES_BUFFER_LENGTH);
try {
if (channel.isConnected()) {
channel.start();
} else {
channel.connect();
}
} catch (JSchException e1) {
throw (IOException) new IOException("Channel connection problems").initCause(e1);
}
readResponse(is);
File f = new File(localFile);
long remain = f.length();
String cMode = mode;
if (cMode == null) {
cMode = "0600";
}
String cline = "C" + cMode + " " + remain + " " + remoteName + "\n";
os.write(cline.getBytes());
os.flush();
readResponse(is);
FileInputStream fis = null;
try {
fis = new FileInputStream(f);
while (remain > 0) {
int trans;
if (remain > buffer.length) {
trans = buffer.length;
} else {
trans = (int) remain;
}
if (fis.read(buffer, 0, trans) != trans) {
throw new IOException("Cannot read enough from local file " + localFile);
}
os.write(buffer, 0, trans);
remain -= trans;
}
fis.close();
} catch (IOException e) {
if (fis != null) {
fis.close();
}
throw (e);
}
os.write(0);
os.flush();
readResponse(is);
os.write("E\n".getBytes());
os.flush();
}
/**
* Receive a file via scp and store it in a stream
*
* @param channel
* ssh channel to use
* @param file
* to receive from remote
* @param target
* to store file into (if null, get only file info)
* @return file information of the file we received
* @throws IOException
* in case of network or protocol trouble
* @throws RemoteScpException
* in case of problems on the target system (connection is fine)
*/
private FileInfo receiveStream(Channel channel, String file, OutputStream targetStream)
throws IOException, RemoteScpException {
byte[] buffer = new byte[BUFFER_SIZE];
OutputStream os = channel.getOutputStream();
InputStream is = channel.getInputStream();
try {
if (channel.isConnected()) {
channel.start();
} else {
channel.connect();
}
} catch (JSchException e1) {
throw (IOException) new IOException("Channel connection problems").initCause(e1);
}
os.write(0x0);
os.flush();
FileInfo fileInfo = new FileInfo();
while (true) {
int c = is.read();
if (c < 0) {
throw new RemoteScpException("Remote scp terminated unexpectedly.");
}
String line = receiveLine(is);
if (c == 'T') {
parseTLine(line, fileInfo);
os.write(0x0);
os.flush();
continue;
}
if ((c == 1) || (c == 2)) {
throw new RemoteScpException("Remote SCP error: " + line);
}
if (c == 'C') {
parseCLine(line, fileInfo);
break;
}
throw new RemoteScpException("Remote SCP error: " + ((char) c) + line);
}
if (targetStream != null) {
os.write(0x0);
os.flush();
try {
long remain = fileInfo.getLength();
while (remain > 0) {
int trans;
if (remain > buffer.length) {
trans = buffer.length;
} else {
trans = (int) remain;
}
int thisTimeReceived = is.read(buffer, 0, trans);
if (thisTimeReceived < 0) {
throw new IOException("Remote scp terminated connection unexpectedly");
}
targetStream.write(buffer, 0, thisTimeReceived);
remain -= thisTimeReceived;
}
targetStream.close();
} catch (IOException e) {
if (targetStream != null) {
targetStream.close();
}
throw (e);
}
readResponse(is);
os.write(0x0);
os.flush();
}
return fileInfo;
}
/**
* @return
* @throws JSchException
*/
private ChannelExec getExecChannel() throws JSchException {
ChannelExec channel;
channel = (ChannelExec) session.openChannel("exec");
return channel;
}
/**
* Copy a local file to a remote site, uses the specified mode when creating the file on the
* remote side.
*
* @param localFile
* Path and name of local file. Must be absolute.
* @param remoteTargetDir
* Remote target directory where the file has to end up (optional)
* @param remoteTargetName
* file name to use on the target system
* @param mode
* a four digit string (e.g., 0644, see "man chmod", "man open")
* @throws IOException
* in case of network problems
* @throws RemoteScpException
* in case of problems on the target system (connection ok)
*/
public void put(String localFile, String remoteTargetDir, String remoteTargetName, String mode)
throws IOException, RemoteScpException {
ChannelExec channel = null;
if ((localFile == null) || (remoteTargetName == null)) {
throw new IllegalArgumentException("Null argument.");
}
if (mode != null) {
if (mode.length() != MODE_LENGTH) {
throw new IllegalArgumentException("Invalid mode.");
}
for (int i = 0; i < mode.length(); i++) {
if (!Character.isDigit(mode.charAt(i))) {
throw new IllegalArgumentException("Invalid mode.");
}
}
}
String cmd = "scp -t ";
if (mode != null) {
cmd = cmd + "-p ";
}
if (remoteTargetDir != null && remoteTargetDir.length() > 0) {
cmd = cmd + "-d " + remoteTargetDir;
}
try {
channel = getExecChannel();
channel.setCommand(cmd);
sendFile(channel, localFile, remoteTargetName, mode);
channel.disconnect();
} catch (JSchException e) {
if (channel != null) {
channel.disconnect();
}
throw (IOException) new IOException("Error during SCP transfer." + e.getMessage())
.initCause(e);
}
}
/**
* Download a file from the remote server to a local file.
*
* @param remoteFile
* Path and name of the remote file.
* @param localTarget
* Local file where to store the data. Must be absolute.
* @throws IOException
* in case of network problems
* @throws RemoteScpException
* in case of problems on the target system (connection ok)
*/
public void get(String remoteFile, String localTarget) throws IOException, RemoteScpException {
File f = new File(localTarget);
FileOutputStream fop = new FileOutputStream(f);
get(remoteFile, fop);
}
/**
* Download a file from the remote server into an OutputStream
*
* @param remoteFile
* Path and name of the remote file.
* @param localTarget
* OutputStream to store the data.
* @throws IOException
* in case of network problems
* @throws RemoteScpException
* in case of problems on the target system (connection ok)
*/
public void get(String remoteFile, OutputStream localTarget) throws IOException,
RemoteScpException {
ChannelExec channel = null;
if ((remoteFile == null) || (localTarget == null)) {
throw new IllegalArgumentException("Null argument.");
}
String cmd = "scp -p -f " + remoteFile;
try {
channel = getExecChannel();
channel.setCommand(cmd);
receiveStream(channel, remoteFile, localTarget);
channel.disconnect();
} catch (JSchException e) {
if (channel != null) {
channel.disconnect();
}
throw (IOException) new IOException("Error during SCP transfer." + e.getMessage())
.initCause(e);
}
}
/**
* Initiates an SCP sequence but stops after getting fileinformation header
*
* @param remoteFile
* to get information for
* @return the file information got
* @throws IOException
* in case of network problems
* @throws RemoteScpException
* in case of problems on the target system (connection ok)
*/
public FileInfo getFileinfo(String remoteFile) throws IOException, RemoteScpException {
ChannelExec channel = null;
FileInfo fileInfo = null;
if (remoteFile == null) {
throw new IllegalArgumentException("Null argument.");
}
String cmd = "scp -p -f \"" + remoteFile + "\"";
try {
channel = getExecChannel();
channel.setCommand(cmd);
fileInfo = receiveStream(channel, remoteFile, null);
channel.disconnect();
} catch (JSchException e) {
throw (IOException) new IOException("Error during SCP transfer." + e.getMessage())
.initCause(e);
} finally {
if (channel != null) {
channel.disconnect();
}
}
return fileInfo;
}
}