/*
* Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* - Neither the name of the Git Development Community nor the
* names of its contributors may be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.spearce.jgit.transport;
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;
import org.spearce.jgit.errors.TransportException;
import org.spearce.jgit.lib.Constants;
import org.spearce.jgit.lib.ObjectId;
import org.spearce.jgit.lib.ProgressMonitor;
import org.spearce.jgit.lib.Ref;
import org.spearce.jgit.lib.Repository;
import org.spearce.jgit.lib.Ref.Storage;
import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.JSchException;
import com.jcraft.jsch.SftpATTRS;
import com.jcraft.jsch.SftpException;
/**
* Transport over the non-Git aware SFTP (SSH based FTP) protocol.
* <p>
* The SFTP transport does not require any specialized Git support on the remote
* (server side) repository. Object files are retrieved directly through secure
* shell's FTP protocol, making it possible to copy objects from a remote
* repository that is available over SSH, but whose remote host does not have
* Git installed.
* <p>
* Unlike the HTTP variant (see {@link TransportHttp}) we rely upon being able
* to list files in directories, as the SFTP protocol supports this function. By
* listing files through SFTP we can avoid needing to have current
* <code>objects/info/packs</code> or <code>info/refs</code> files on the
* remote repository and access the data directly, much as Git itself would.
* <p>
* Concurrent pushing over this transport is not supported. Multiple concurrent
* push operations may cause confusion in the repository state.
*
* @see WalkFetchConnection
*/
public class TransportSftp extends SshTransport implements WalkTransport {
static boolean canHandle(final URIish uri) {
return uri.isRemote() && "sftp".equals(uri.getScheme());
}
TransportSftp(final Repository local, final URIish uri) {
super(local, uri);
}
@Override
public FetchConnection openFetch() throws TransportException {
final SftpObjectDB c = new SftpObjectDB(uri.getPath());
final WalkFetchConnection r = new WalkFetchConnection(this, c);
r.available(c.readAdvertisedRefs());
return r;
}
@Override
public PushConnection openPush() throws TransportException {
final SftpObjectDB c = new SftpObjectDB(uri.getPath());
final WalkPushConnection r = new WalkPushConnection(this, c);
r.available(c.readAdvertisedRefs());
return r;
}
ChannelSftp newSftp() throws TransportException {
initSession();
final int tms = getTimeout() > 0 ? getTimeout() * 1000 : 0;
try {
final Channel channel = sock.openChannel("sftp");
channel.connect(tms);
return (ChannelSftp) channel;
} catch (JSchException je) {
throw new TransportException(uri, je.getMessage(), je);
}
}
class SftpObjectDB extends WalkRemoteObjectDatabase {
private final String objectsPath;
private ChannelSftp ftp;
SftpObjectDB(String path) throws TransportException {
if (path.startsWith("/~"))
path = path.substring(1);
if (path.startsWith("~/"))
path = path.substring(2);
try {
ftp = newSftp();
ftp.cd(path);
ftp.cd("objects");
objectsPath = ftp.pwd();
} catch (TransportException err) {
close();
throw err;
} catch (SftpException je) {
throw new TransportException("Can't enter " + path + "/objects"
+ ": " + je.getMessage(), je);
}
}
SftpObjectDB(final SftpObjectDB parent, final String p)
throws TransportException {
try {
ftp = newSftp();
ftp.cd(parent.objectsPath);
ftp.cd(p);
objectsPath = ftp.pwd();
} catch (TransportException err) {
close();
throw err;
} catch (SftpException je) {
throw new TransportException("Can't enter " + p + " from "
+ parent.objectsPath + ": " + je.getMessage(), je);
}
}
@Override
URIish getURI() {
return uri.setPath(objectsPath);
}
@Override
Collection<WalkRemoteObjectDatabase> getAlternates() throws IOException {
try {
return readAlternates(INFO_ALTERNATES);
} catch (FileNotFoundException err) {
return null;
}
}
@Override
WalkRemoteObjectDatabase openAlternate(final String location)
throws IOException {
return new SftpObjectDB(this, location);
}
@Override
Collection<String> getPackNames() throws IOException {
final List<String> packs = new ArrayList<String>();
try {
final Collection<ChannelSftp.LsEntry> list = ftp.ls("pack");
final HashMap<String, ChannelSftp.LsEntry> files;
final HashMap<String, Integer> mtimes;
files = new HashMap<String, ChannelSftp.LsEntry>();
mtimes = new HashMap<String, Integer>();
for (final ChannelSftp.LsEntry ent : list)
files.put(ent.getFilename(), ent);
for (final ChannelSftp.LsEntry ent : list) {
final String n = ent.getFilename();
if (!n.startsWith("pack-") || !n.endsWith(".pack"))
continue;
final String in = n.substring(0, n.length() - 5) + ".idx";
if (!files.containsKey(in))
continue;
mtimes.put(n, ent.getAttrs().getMTime());
packs.add(n);
}
Collections.sort(packs, new Comparator<String>() {
public int compare(final String o1, final String o2) {
return mtimes.get(o2) - mtimes.get(o1);
}
});
} catch (SftpException je) {
throw new TransportException("Can't ls " + objectsPath
+ "/pack: " + je.getMessage(), je);
}
return packs;
}
@Override
FileStream open(final String path) throws IOException {
try {
final SftpATTRS a = ftp.lstat(path);
return new FileStream(ftp.get(path), a.getSize());
} catch (SftpException je) {
if (je.id == ChannelSftp.SSH_FX_NO_SUCH_FILE)
throw new FileNotFoundException(path);
throw new TransportException("Can't get " + objectsPath + "/"
+ path + ": " + je.getMessage(), je);
}
}
@Override
void deleteFile(final String path) throws IOException {
try {
ftp.rm(path);
} catch (SftpException je) {
if (je.id == ChannelSftp.SSH_FX_NO_SUCH_FILE)
return;
throw new TransportException("Can't delete " + objectsPath
+ "/" + path + ": " + je.getMessage(), je);
}
// Prune any now empty directories.
//
String dir = path;
int s = dir.lastIndexOf('/');
while (s > 0) {
try {
dir = dir.substring(0, s);
ftp.rmdir(dir);
s = dir.lastIndexOf('/');
} catch (SftpException je) {
// If we cannot delete it, leave it alone. It may have
// entries still in it, or maybe we lack write access on
// the parent. Either way it isn't a fatal error.
//
break;
}
}
}
@Override
OutputStream writeFile(final String path,
final ProgressMonitor monitor, final String monitorTask)
throws IOException {
try {
return ftp.put(path);
} catch (SftpException je) {
if (je.id == ChannelSftp.SSH_FX_NO_SUCH_FILE) {
mkdir_p(path);
try {
return ftp.put(path);
} catch (SftpException je2) {
je = je2;
}
}
throw new TransportException("Can't write " + objectsPath + "/"
+ path + ": " + je.getMessage(), je);
}
}
@Override
void writeFile(final String path, final byte[] data) throws IOException {
final String lock = path + ".lock";
try {
super.writeFile(lock, data);
try {
ftp.rename(lock, path);
} catch (SftpException je) {
throw new TransportException("Can't write " + objectsPath
+ "/" + path + ": " + je.getMessage(), je);
}
} catch (IOException err) {
try {
ftp.rm(lock);
} catch (SftpException e) {
// Ignore deletion failure, we are already
// failing anyway.
}
throw err;
}
}
private void mkdir_p(String path) throws IOException {
final int s = path.lastIndexOf('/');
if (s <= 0)
return;
path = path.substring(0, s);
try {
ftp.mkdir(path);
} catch (SftpException je) {
if (je.id == ChannelSftp.SSH_FX_NO_SUCH_FILE) {
mkdir_p(path);
try {
ftp.mkdir(path);
return;
} catch (SftpException je2) {
je = je2;
}
}
throw new TransportException("Can't mkdir " + objectsPath + "/"
+ path + ": " + je.getMessage(), je);
}
}
Map<String, Ref> readAdvertisedRefs() throws TransportException {
final TreeMap<String, Ref> avail = new TreeMap<String, Ref>();
readPackedRefs(avail);
readRef(avail, ROOT_DIR + Constants.HEAD, Constants.HEAD);
readLooseRefs(avail, ROOT_DIR + "refs", "refs/");
return avail;
}
private void readLooseRefs(final TreeMap<String, Ref> avail,
final String dir, final String prefix)
throws TransportException {
final Collection<ChannelSftp.LsEntry> list;
try {
list = ftp.ls(dir);
} catch (SftpException je) {
throw new TransportException("Can't ls " + objectsPath + "/"
+ dir + ": " + je.getMessage(), je);
}
for (final ChannelSftp.LsEntry ent : list) {
final String n = ent.getFilename();
if (".".equals(n) || "..".equals(n))
continue;
final String nPath = dir + "/" + n;
if (ent.getAttrs().isDir())
readLooseRefs(avail, nPath, prefix + n + "/");
else
readRef(avail, nPath, prefix + n);
}
}
private Ref readRef(final TreeMap<String, Ref> avail,
final String path, final String name) throws TransportException {
final String line;
try {
final BufferedReader br = openReader(path);
try {
line = br.readLine();
} finally {
br.close();
}
} catch (FileNotFoundException noRef) {
return null;
} catch (IOException err) {
throw new TransportException("Cannot read " + objectsPath + "/"
+ path + ": " + err.getMessage(), err);
}
if (line == null)
throw new TransportException("Empty ref: " + name);
if (line.startsWith("ref: ")) {
final String p = line.substring("ref: ".length());
Ref r = readRef(avail, ROOT_DIR + p, p);
if (r == null)
r = avail.get(p);
if (r != null) {
r = new Ref(loose(r), name, r.getObjectId(), r
.getPeeledObjectId(), true);
avail.put(name, r);
}
return r;
}
if (ObjectId.isId(line)) {
final Ref r = new Ref(loose(avail.get(name)), name, ObjectId
.fromString(line));
avail.put(r.getName(), r);
return r;
}
throw new TransportException("Bad ref: " + name + ": " + line);
}
private Storage loose(final Ref r) {
if (r != null && r.getStorage() == Storage.PACKED)
return Storage.LOOSE_PACKED;
return Storage.LOOSE;
}
@Override
void close() {
if (ftp != null) {
try {
if (ftp.isConnected())
ftp.disconnect();
} finally {
ftp = null;
}
}
}
}
}