/*
* Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
* and other copyright owners as documented in the project's IP log.
*
* This program and the accompanying materials are made available
* under the terms of the Eclipse Distribution License v1.0 which
* accompanies this distribution, is reproduced below, and is
* available at http://www.eclipse.org/org/documents/edl-v10.php
*
* 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 Eclipse Foundation, Inc. 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.eclipse.jgit.transport;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.Proxy;
import java.net.ProxySelector;
import java.net.URL;
import java.net.URLConnection;
import java.security.DigestOutputStream;
import java.security.InvalidKeyException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.spec.InvalidKeySpecException;
import java.text.MessageFormat;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Date;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Properties;
import java.util.Set;
import java.util.SortedMap;
import java.util.TimeZone;
import java.util.TreeMap;
import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import org.eclipse.jgit.JGitText;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.lib.NullProgressMonitor;
import org.eclipse.jgit.lib.ProgressMonitor;
import org.eclipse.jgit.util.Base64;
import org.eclipse.jgit.util.HttpSupport;
import org.eclipse.jgit.util.StringUtils;
import org.eclipse.jgit.util.TemporaryBuffer;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
import org.xml.sax.helpers.XMLReaderFactory;
/**
* A simple HTTP REST client for the Amazon S3 service.
* <p>
* This client uses the REST API to communicate with the Amazon S3 servers and
* read or write content through a bucket that the user has access to. It is a
* very lightweight implementation of the S3 API and therefore does not have all
* of the bells and whistles of popular client implementations.
* <p>
* Authentication is always performed using the user's AWSAccessKeyId and their
* private AWSSecretAccessKey.
* <p>
* Optional client-side encryption may be enabled if requested. The format is
* compatible with <a href="http://jets3t.s3.amazonaws.com/index.html">jets3t</a>,
* a popular Java based Amazon S3 client library. Enabling encryption can hide
* sensitive data from the operators of the S3 service.
*/
public class AmazonS3 {
private static final Set<String> SIGNED_HEADERS;
private static final String HMAC = "HmacSHA1";
private static final String DOMAIN = "s3.amazonaws.com";
private static final String X_AMZ_ACL = "x-amz-acl";
private static final String X_AMZ_META = "x-amz-meta-";
static {
SIGNED_HEADERS = new HashSet<String>();
SIGNED_HEADERS.add("content-type");
SIGNED_HEADERS.add("content-md5");
SIGNED_HEADERS.add("date");
}
private static boolean isSignedHeader(final String name) {
final String nameLC = StringUtils.toLowerCase(name);
return SIGNED_HEADERS.contains(nameLC) || nameLC.startsWith("x-amz-");
}
private static String toCleanString(final List<String> list) {
final StringBuilder s = new StringBuilder();
for (final String v : list) {
if (s.length() > 0)
s.append(',');
s.append(v.replaceAll("\n", "").trim());
}
return s.toString();
}
private static String remove(final Map<String, String> m, final String k) {
final String r = m.remove(k);
return r != null ? r : "";
}
private static String httpNow() {
final String tz = "GMT";
final SimpleDateFormat fmt;
fmt = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss", Locale.US);
fmt.setTimeZone(TimeZone.getTimeZone(tz));
return fmt.format(new Date()) + " " + tz;
}
private static MessageDigest newMD5() {
try {
return MessageDigest.getInstance("MD5");
} catch (NoSuchAlgorithmException e) {
throw new RuntimeException(JGitText.get().JRELacksMD5Implementation, e);
}
}
/** AWSAccessKeyId, public string that identifies the user's account. */
private final String publicKey;
/** Decoded form of the private AWSSecretAccessKey, to sign requests. */
private final SecretKeySpec privateKey;
/** Our HTTP proxy support, in case we are behind a firewall. */
private final ProxySelector proxySelector;
/** ACL to apply to created objects. */
private final String acl;
/** Maximum number of times to try an operation. */
private final int maxAttempts;
/** Encryption algorithm, may be a null instance that provides pass-through. */
private final WalkEncryption encryption;
/**
* Create a new S3 client for the supplied user information.
* <p>
* The connection properties are a subset of those supported by the popular
* <a href="http://jets3t.s3.amazonaws.com/index.html">jets3t</a> library.
* For example:
*
* <pre>
* # AWS Access and Secret Keys (required)
* accesskey: <YourAWSAccessKey>
* secretkey: <YourAWSSecretKey>
*
* # Access Control List setting to apply to uploads, must be one of:
* # PRIVATE, PUBLIC_READ (defaults to PRIVATE).
* acl: PRIVATE
*
* # Number of times to retry after internal error from S3.
* httpclient.retry-max: 3
*
* # End-to-end encryption (hides content from S3 owners)
* password: <encryption pass-phrase>
* crypto.algorithm: PBEWithMD5AndDES
* </pre>
*
* @param props
* connection properties.
*
*/
public AmazonS3(final Properties props) {
publicKey = props.getProperty("accesskey");
if (publicKey == null)
throw new IllegalArgumentException(JGitText.get().missingAccesskey);
final String secret = props.getProperty("secretkey");
if (secret == null)
throw new IllegalArgumentException(JGitText.get().missingSecretkey);
privateKey = new SecretKeySpec(Constants.encodeASCII(secret), HMAC);
final String pacl = props.getProperty("acl", "PRIVATE");
if (StringUtils.equalsIgnoreCase("PRIVATE", pacl))
acl = "private";
else if (StringUtils.equalsIgnoreCase("PUBLIC", pacl))
acl = "public-read";
else if (StringUtils.equalsIgnoreCase("PUBLIC-READ", pacl))
acl = "public-read";
else if (StringUtils.equalsIgnoreCase("PUBLIC_READ", pacl))
acl = "public-read";
else
throw new IllegalArgumentException("Invalid acl: " + pacl);
try {
final String cPas = props.getProperty("password");
if (cPas != null) {
String cAlg = props.getProperty("crypto.algorithm");
if (cAlg == null)
cAlg = "PBEWithMD5AndDES";
encryption = new WalkEncryption.ObjectEncryptionV2(cAlg, cPas);
} else {
encryption = WalkEncryption.NONE;
}
} catch (InvalidKeySpecException e) {
throw new IllegalArgumentException(JGitText.get().invalidEncryption, e);
} catch (NoSuchAlgorithmException e) {
throw new IllegalArgumentException(JGitText.get().invalidEncryption, e);
}
maxAttempts = Integer.parseInt(props.getProperty(
"httpclient.retry-max", "3"));
proxySelector = ProxySelector.getDefault();
}
/**
* Get the content of a bucket object.
*
* @param bucket
* name of the bucket storing the object.
* @param key
* key of the object within its bucket.
* @return connection to stream the content of the object. The request
* properties of the connection may not be modified by the caller as
* the request parameters have already been signed.
* @throws IOException
* sending the request was not possible.
*/
public URLConnection get(final String bucket, final String key)
throws IOException {
for (int curAttempt = 0; curAttempt < maxAttempts; curAttempt++) {
final HttpURLConnection c = open("GET", bucket, key);
authorize(c);
switch (HttpSupport.response(c)) {
case HttpURLConnection.HTTP_OK:
encryption.validate(c, X_AMZ_META);
return c;
case HttpURLConnection.HTTP_NOT_FOUND:
throw new FileNotFoundException(key);
case HttpURLConnection.HTTP_INTERNAL_ERROR:
continue;
default:
throw error("Reading", key, c);
}
}
throw maxAttempts("Reading", key);
}
/**
* Decrypt an input stream from {@link #get(String, String)}.
*
* @param u
* connection previously created by {@link #get(String, String)}}.
* @return stream to read plain text from.
* @throws IOException
* decryption could not be configured.
*/
public InputStream decrypt(final URLConnection u) throws IOException {
return encryption.decrypt(u.getInputStream());
}
/**
* List the names of keys available within a bucket.
* <p>
* This method is primarily meant for obtaining a "recursive directory
* listing" rooted under the specified bucket and prefix location.
*
* @param bucket
* name of the bucket whose objects should be listed.
* @param prefix
* common prefix to filter the results by. Must not be null.
* Supplying the empty string will list all keys in the bucket.
* Supplying a non-empty string will act as though a trailing '/'
* appears in prefix, even if it does not.
* @return list of keys starting with <code>prefix</code>, after removing
* <code>prefix</code> (or <code>prefix + "/"</code>)from all
* of them.
* @throws IOException
* sending the request was not possible, or the response XML
* document could not be parsed properly.
*/
public List<String> list(final String bucket, String prefix)
throws IOException {
if (prefix.length() > 0 && !prefix.endsWith("/"))
prefix += "/";
final ListParser lp = new ListParser(bucket, prefix);
do {
lp.list();
} while (lp.truncated);
return lp.entries;
}
/**
* Delete a single object.
* <p>
* Deletion always succeeds, even if the object does not exist.
*
* @param bucket
* name of the bucket storing the object.
* @param key
* key of the object within its bucket.
* @throws IOException
* deletion failed due to communications error.
*/
public void delete(final String bucket, final String key)
throws IOException {
for (int curAttempt = 0; curAttempt < maxAttempts; curAttempt++) {
final HttpURLConnection c = open("DELETE", bucket, key);
authorize(c);
switch (HttpSupport.response(c)) {
case HttpURLConnection.HTTP_NO_CONTENT:
return;
case HttpURLConnection.HTTP_INTERNAL_ERROR:
continue;
default:
throw error("Deletion", key, c);
}
}
throw maxAttempts("Deletion", key);
}
/**
* Atomically create or replace a single small object.
* <p>
* This form is only suitable for smaller contents, where the caller can
* reasonable fit the entire thing into memory.
* <p>
* End-to-end data integrity is assured by internally computing the MD5
* checksum of the supplied data and transmitting the checksum along with
* the data itself.
*
* @param bucket
* name of the bucket storing the object.
* @param key
* key of the object within its bucket.
* @param data
* new data content for the object. Must not be null. Zero length
* array will create a zero length object.
* @throws IOException
* creation/updating failed due to communications error.
*/
public void put(final String bucket, final String key, final byte[] data)
throws IOException {
if (encryption != WalkEncryption.NONE) {
// We have to copy to produce the cipher text anyway so use
// the large object code path as it supports that behavior.
//
final OutputStream os = beginPut(bucket, key, null, null);
os.write(data);
os.close();
return;
}
final String md5str = Base64.encodeBytes(newMD5().digest(data));
final String lenstr = String.valueOf(data.length);
for (int curAttempt = 0; curAttempt < maxAttempts; curAttempt++) {
final HttpURLConnection c = open("PUT", bucket, key);
c.setRequestProperty("Content-Length", lenstr);
c.setRequestProperty("Content-MD5", md5str);
c.setRequestProperty(X_AMZ_ACL, acl);
authorize(c);
c.setDoOutput(true);
c.setFixedLengthStreamingMode(data.length);
final OutputStream os = c.getOutputStream();
try {
os.write(data);
} finally {
os.close();
}
switch (HttpSupport.response(c)) {
case HttpURLConnection.HTTP_OK:
return;
case HttpURLConnection.HTTP_INTERNAL_ERROR:
continue;
default:
throw error("Writing", key, c);
}
}
throw maxAttempts("Writing", key);
}
/**
* Atomically create or replace a single large object.
* <p>
* Initially the returned output stream buffers data into memory, but if the
* total number of written bytes starts to exceed an internal limit the data
* is spooled to a temporary file on the local drive.
* <p>
* Network transmission is attempted only when <code>close()</code> gets
* called at the end of output. Closing the returned stream can therefore
* take significant time, especially if the written content is very large.
* <p>
* End-to-end data integrity is assured by internally computing the MD5
* checksum of the supplied data and transmitting the checksum along with
* the data itself.
*
* @param bucket
* name of the bucket storing the object.
* @param key
* key of the object within its bucket.
* @param monitor
* (optional) progress monitor to post upload completion to
* during the stream's close method.
* @param monitorTask
* (optional) task name to display during the close method.
* @return a stream which accepts the new data, and transmits once closed.
* @throws IOException
* if encryption was enabled it could not be configured.
*/
public OutputStream beginPut(final String bucket, final String key,
final ProgressMonitor monitor, final String monitorTask)
throws IOException {
final MessageDigest md5 = newMD5();
final TemporaryBuffer buffer = new TemporaryBuffer.LocalFile() {
@Override
public void close() throws IOException {
super.close();
try {
putImpl(bucket, key, md5.digest(), this, monitor,
monitorTask);
} finally {
destroy();
}
}
};
return encryption.encrypt(new DigestOutputStream(buffer, md5));
}
private void putImpl(final String bucket, final String key,
final byte[] csum, final TemporaryBuffer buf,
ProgressMonitor monitor, String monitorTask) throws IOException {
if (monitor == null)
monitor = NullProgressMonitor.INSTANCE;
if (monitorTask == null)
monitorTask = MessageFormat.format(JGitText.get().progressMonUploading, key);
final String md5str = Base64.encodeBytes(csum);
final long len = buf.length();
final String lenstr = String.valueOf(len);
for (int curAttempt = 0; curAttempt < maxAttempts; curAttempt++) {
final HttpURLConnection c = open("PUT", bucket, key);
c.setRequestProperty("Content-Length", lenstr);
c.setRequestProperty("Content-MD5", md5str);
c.setRequestProperty(X_AMZ_ACL, acl);
encryption.request(c, X_AMZ_META);
authorize(c);
c.setDoOutput(true);
c.setFixedLengthStreamingMode((int) len);
monitor.beginTask(monitorTask, (int) (len / 1024));
final OutputStream os = c.getOutputStream();
try {
buf.writeTo(os, monitor);
} finally {
monitor.endTask();
os.close();
}
switch (HttpSupport.response(c)) {
case HttpURLConnection.HTTP_OK:
return;
case HttpURLConnection.HTTP_INTERNAL_ERROR:
continue;
default:
throw error("Writing", key, c);
}
}
throw maxAttempts("Writing", key);
}
private IOException error(final String action, final String key,
final HttpURLConnection c) throws IOException {
final IOException err = new IOException(MessageFormat.format(JGitText.get().amazonS3ActionFailed
, action, key, HttpSupport.response(c), c.getResponseMessage()));
final ByteArrayOutputStream b = new ByteArrayOutputStream();
byte[] buf = new byte[2048];
for (;;) {
final int n = c.getErrorStream().read(buf);
if (n < 0)
break;
if (n > 0)
b.write(buf, 0, n);
}
buf = b.toByteArray();
if (buf.length > 0)
err.initCause(new IOException("\n" + new String(buf)));
return err;
}
private IOException maxAttempts(final String action, final String key) {
return new IOException(MessageFormat.format(JGitText.get().amazonS3ActionFailedGivingUp
, action, key, maxAttempts));
}
private HttpURLConnection open(final String method, final String bucket,
final String key) throws IOException {
final Map<String, String> noArgs = Collections.emptyMap();
return open(method, bucket, key, noArgs);
}
private HttpURLConnection open(final String method, final String bucket,
final String key, final Map<String, String> args)
throws IOException {
final StringBuilder urlstr = new StringBuilder();
urlstr.append("http://");
urlstr.append(bucket);
urlstr.append('.');
urlstr.append(DOMAIN);
urlstr.append('/');
if (key.length() > 0)
HttpSupport.encode(urlstr, key);
if (!args.isEmpty()) {
final Iterator<Map.Entry<String, String>> i;
urlstr.append('?');
i = args.entrySet().iterator();
while (i.hasNext()) {
final Map.Entry<String, String> e = i.next();
urlstr.append(e.getKey());
urlstr.append('=');
HttpSupport.encode(urlstr, e.getValue());
if (i.hasNext())
urlstr.append('&');
}
}
final URL url = new URL(urlstr.toString());
final Proxy proxy = HttpSupport.proxyFor(proxySelector, url);
final HttpURLConnection c;
c = (HttpURLConnection) url.openConnection(proxy);
c.setRequestMethod(method);
c.setRequestProperty("User-Agent", "jgit/1.0");
c.setRequestProperty("Date", httpNow());
return c;
}
private void authorize(final HttpURLConnection c) throws IOException {
final Map<String, List<String>> reqHdr = c.getRequestProperties();
final SortedMap<String, String> sigHdr = new TreeMap<String, String>();
for (final Map.Entry<String, List<String>> entry : reqHdr.entrySet()) {
final String hdr = entry.getKey();
if (isSignedHeader(hdr))
sigHdr.put(StringUtils.toLowerCase(hdr), toCleanString(entry.getValue()));
}
final StringBuilder s = new StringBuilder();
s.append(c.getRequestMethod());
s.append('\n');
s.append(remove(sigHdr, "content-md5"));
s.append('\n');
s.append(remove(sigHdr, "content-type"));
s.append('\n');
s.append(remove(sigHdr, "date"));
s.append('\n');
for (final Map.Entry<String, String> e : sigHdr.entrySet()) {
s.append(e.getKey());
s.append(':');
s.append(e.getValue());
s.append('\n');
}
final String host = c.getURL().getHost();
s.append('/');
s.append(host.substring(0, host.length() - DOMAIN.length() - 1));
s.append(c.getURL().getPath());
final String sec;
try {
final Mac m = Mac.getInstance(HMAC);
m.init(privateKey);
sec = Base64.encodeBytes(m.doFinal(s.toString().getBytes("UTF-8")));
} catch (NoSuchAlgorithmException e) {
throw new IOException(MessageFormat.format(JGitText.get().noHMACsupport, HMAC, e.getMessage()));
} catch (InvalidKeyException e) {
throw new IOException(MessageFormat.format(JGitText.get().invalidKey, e.getMessage()));
}
c.setRequestProperty("Authorization", "AWS " + publicKey + ":" + sec);
}
static Properties properties(final File authFile)
throws FileNotFoundException, IOException {
final Properties p = new Properties();
final FileInputStream in = new FileInputStream(authFile);
try {
p.load(in);
} finally {
in.close();
}
return p;
}
private final class ListParser extends DefaultHandler {
final List<String> entries = new ArrayList<String>();
private final String bucket;
private final String prefix;
boolean truncated;
private StringBuilder data;
ListParser(final String bn, final String p) {
bucket = bn;
prefix = p;
}
void list() throws IOException {
final Map<String, String> args = new TreeMap<String, String>();
if (prefix.length() > 0)
args.put("prefix", prefix);
if (!entries.isEmpty())
args.put("marker", prefix + entries.get(entries.size() - 1));
for (int curAttempt = 0; curAttempt < maxAttempts; curAttempt++) {
final HttpURLConnection c = open("GET", bucket, "", args);
authorize(c);
switch (HttpSupport.response(c)) {
case HttpURLConnection.HTTP_OK:
truncated = false;
data = null;
final XMLReader xr;
try {
xr = XMLReaderFactory.createXMLReader();
} catch (SAXException e) {
throw new IOException(JGitText.get().noXMLParserAvailable);
}
xr.setContentHandler(this);
final InputStream in = c.getInputStream();
try {
xr.parse(new InputSource(in));
} catch (SAXException parsingError) {
final IOException p;
p = new IOException(MessageFormat.format(JGitText.get().errorListing, prefix));
p.initCause(parsingError);
throw p;
} finally {
in.close();
}
return;
case HttpURLConnection.HTTP_INTERNAL_ERROR:
continue;
default:
throw AmazonS3.this.error("Listing", prefix, c);
}
}
throw maxAttempts("Listing", prefix);
}
@Override
public void startElement(final String uri, final String name,
final String qName, final Attributes attributes)
throws SAXException {
if ("Key".equals(name) || "IsTruncated".equals(name))
data = new StringBuilder();
}
@Override
public void ignorableWhitespace(final char[] ch, final int s,
final int n) throws SAXException {
if (data != null)
data.append(ch, s, n);
}
@Override
public void characters(final char[] ch, final int s, final int n)
throws SAXException {
if (data != null)
data.append(ch, s, n);
}
@Override
public void endElement(final String uri, final String name,
final String qName) throws SAXException {
if ("Key".equals(name))
entries.add(data.toString().substring(prefix.length()));
else if ("IsTruncated".equals(name))
truncated = StringUtils.equalsIgnoreCase("true", data.toString());
data = null;
}
}
}