org.apache.sshd.server.keyprovider.SimpleGeneratorHostKeyProvider Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* 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.sshd.server.keyprovider;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectStreamClass;
import java.io.ObjectStreamConstants;
import java.io.OutputStream;
import java.io.StreamCorruptedException;
import java.nio.file.Path;
import java.security.GeneralSecurityException;
import java.security.KeyPair;
import java.security.spec.InvalidKeySpecException;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
import org.apache.sshd.common.NamedResource;
import org.apache.sshd.common.config.keys.writer.openssh.OpenSSHKeyPairResourceWriter;
import org.apache.sshd.common.session.SessionContext;
import org.apache.sshd.common.util.security.SecurityUtils;
/**
* A simple implementation of an {@link AbstractGeneratorHostKeyProvider} that writes and reads host keys using the
* OpenSSH file format. Legacy keys written by earlier implementations used Java serialization. De-serializing is
* restricted to a small number of classes known to exist in serialized {@link KeyPair}s.
*
* @author Apache MINA SSHD Project
*/
public class SimpleGeneratorHostKeyProvider extends AbstractGeneratorHostKeyProvider {
public SimpleGeneratorHostKeyProvider() {
super();
}
public SimpleGeneratorHostKeyProvider(Path path) {
setPath(path);
}
@Override
protected Iterable doReadKeyPairs(SessionContext session, NamedResource resourceKey, InputStream inputStream)
throws IOException, GeneralSecurityException {
try (BufferedInputStream in = new BufferedInputStream(inputStream)) {
if (isJavaSerialization(in, resourceKey)) {
try (ObjectInputStream r = new ValidatingObjectInputStream(in)) {
return Collections.singletonList((KeyPair) r.readObject());
} catch (ClassNotFoundException e) {
throw new InvalidKeySpecException(
"Cannot de-serialize " + resourceKey + ": missing classes: " + e.getMessage(), e);
}
} else {
return SecurityUtils.loadKeyPairIdentities(null, resourceKey, in, null);
}
}
}
private boolean isJavaSerialization(BufferedInputStream in, NamedResource resourceKey) throws IOException {
in.mark(2);
try {
byte[] magicBytes = new byte[2];
int length = in.read(magicBytes);
if (length != 2) {
throw new StreamCorruptedException("File " + resourceKey + " is not a host key");
}
short magic = (short) (((magicBytes[0] & 0xFF) << 8) | (magicBytes[1] & 0xFF));
return magic == ObjectStreamConstants.STREAM_MAGIC;
} finally {
in.reset();
}
}
@Override
protected void doWriteKeyPair(NamedResource resourceKey, KeyPair kp, OutputStream outputStream)
throws IOException, GeneralSecurityException {
OpenSSHKeyPairResourceWriter writer = new OpenSSHKeyPairResourceWriter();
try (OutputStream out = outputStream) {
writer.writePrivateKey(kp, "host key", null, out);
}
}
private static class ValidatingObjectInputStream extends ObjectInputStream {
private static final Set ALLOWED = new HashSet<>();
static {
ALLOWED.add("[B"); // byte[], used in BC EC key serialization
ALLOWED.add("java.lang.Enum");
ALLOWED.add("java.lang.Number");
ALLOWED.add("java.lang.String");
ALLOWED.add("java.math.BigInteger"); // Used in BC DSA/RSA
ALLOWED.add("java.security.KeyPair");
ALLOWED.add("java.security.PublicKey");
ALLOWED.add("java.security.PrivateKey");
ALLOWED.add("java.security.KeyRep");
ALLOWED.add("java.security.KeyRep$Type");
ALLOWED.add("org.bouncycastle.jcajce.provider.asymmetric.dsa.BCDSAPrivateKey");
ALLOWED.add("org.bouncycastle.jcajce.provider.asymmetric.dsa.BCDSAPublicKey");
ALLOWED.add("org.bouncycastle.jcajce.provider.asymmetric.rsa.BCRSAPrivateCrtKey");
ALLOWED.add("org.bouncycastle.jcajce.provider.asymmetric.rsa.BCRSAPrivateKey");
ALLOWED.add("org.bouncycastle.jcajce.provider.asymmetric.rsa.BCRSAPublicKey");
ALLOWED.add("org.bouncycastle.jcajce.provider.asymmetric.ec.BCECPrivateKey");
ALLOWED.add("org.bouncycastle.jcajce.provider.asymmetric.ec.BCECPublicKey");
ALLOWED.add("com.android.org.bouncycastle.jcajce.provider.asymmetric.dsa.BCDSAPrivateKey");
ALLOWED.add("com.android.org.bouncycastle.jcajce.provider.asymmetric.dsa.BCDSAPublicKey");
ALLOWED.add("com.android.org.bouncycastle.jcajce.provider.asymmetric.rsa.BCRSAPrivateCrtKey");
ALLOWED.add("com.android.org.bouncycastle.jcajce.provider.asymmetric.rsa.BCRSAPrivateKey");
ALLOWED.add("com.android.org.bouncycastle.jcajce.provider.asymmetric.rsa.BCRSAPublicKey");
ALLOWED.add("com.android.org.bouncycastle.jcajce.provider.asymmetric.ec.BCECPrivateKey");
ALLOWED.add("com.android.org.bouncycastle.jcajce.provider.asymmetric.ec.BCECPublicKey");
// net.i2p EdDSA keys cannot be serialized anyway; so no need to whitelist any of their classes.
// They use the default serialization, which writes a great many different classes, but at least
// one of them does not implement Serializable, and thus writing runs into a NotSerializableException.
}
ValidatingObjectInputStream(InputStream in) throws IOException {
super(in);
}
@Override
protected Class resolveClass(ObjectStreamClass desc) throws IOException, ClassNotFoundException {
validate(desc.getName());
return super.resolveClass(desc);
}
private void validate(String className) throws IOException {
if (!ALLOWED.contains(className)) {
throw new IOException(className + " blocked for deserialization");
}
}
}
}