Kotlin conversion: HardwareSecurity

This commit is contained in:
Paul Schaub 2023-09-06 11:49:39 +02:00
parent 3115e13bc2
commit b09979fa45
Signed by: vanitasvitae
GPG Key ID: 62BEE9264BF17311
2 changed files with 76 additions and 105 deletions

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@ -1,105 +0,0 @@
// SPDX-FileCopyrightText: 2022 Paul Schaub <vanitasvitae@fsfe.org>
//
// SPDX-License-Identifier: Apache-2.0
package org.pgpainless.decryption_verification;
import org.bouncycastle.bcpg.AEADEncDataPacket;
import org.bouncycastle.bcpg.SymmetricEncIntegrityPacket;
import org.bouncycastle.openpgp.PGPException;
import org.bouncycastle.openpgp.PGPSessionKey;
import org.bouncycastle.openpgp.operator.PGPDataDecryptor;
import org.bouncycastle.openpgp.operator.PublicKeyDataDecryptorFactory;
import org.bouncycastle.openpgp.operator.bc.BcPublicKeyDataDecryptorFactory;
import org.pgpainless.key.SubkeyIdentifier;
/**
* Enable integration of hardware-backed OpenPGP keys.
*/
public class HardwareSecurity {
public interface DecryptionCallback {
/**
* Delegate decryption of a Public-Key-Encrypted-Session-Key (PKESK) to an external API for dealing with
* hardware security modules such as smartcards or TPMs.
*
* If decryption fails for some reason, a subclass of the {@link HardwareSecurityException} is thrown.
*
* @param keyId id of the key
* @param keyAlgorithm algorithm
* @param sessionKeyData encrypted session key
*
* @return decrypted session key
* @throws HardwareSecurityException exception
*/
byte[] decryptSessionKey(long keyId, int keyAlgorithm, byte[] sessionKeyData)
throws HardwareSecurityException;
}
/**
* Implementation of {@link PublicKeyDataDecryptorFactory} which delegates decryption of encrypted session keys
* to a {@link DecryptionCallback}.
* Users can provide such a callback to delegate decryption of messages to hardware security SDKs.
*/
public static class HardwareDataDecryptorFactory implements CustomPublicKeyDataDecryptorFactory {
private final DecryptionCallback callback;
// luckily we can instantiate the BcPublicKeyDataDecryptorFactory with null as argument.
private final PublicKeyDataDecryptorFactory factory =
new BcPublicKeyDataDecryptorFactory(null);
private final SubkeyIdentifier subkey;
/**
* Create a new {@link HardwareDataDecryptorFactory}.
*
* @param subkeyIdentifier identifier of the decryption subkey
* @param callback decryption callback
*/
public HardwareDataDecryptorFactory(SubkeyIdentifier subkeyIdentifier, DecryptionCallback callback) {
this.callback = callback;
this.subkey = subkeyIdentifier;
}
@Override
public byte[] recoverSessionData(int keyAlgorithm, byte[][] secKeyData)
throws PGPException {
try {
// delegate decryption to the callback
return callback.decryptSessionKey(subkey.getSubkeyId(), keyAlgorithm, secKeyData[0]);
} catch (HardwareSecurityException e) {
throw new PGPException("Hardware-backed decryption failed.", e);
}
}
@Override
public PGPDataDecryptor createDataDecryptor(boolean withIntegrityPacket, int encAlgorithm, byte[] key)
throws PGPException {
return factory.createDataDecryptor(withIntegrityPacket, encAlgorithm, key);
}
@Override
public PGPDataDecryptor createDataDecryptor(AEADEncDataPacket aeadEncDataPacket, PGPSessionKey sessionKey)
throws PGPException {
return factory.createDataDecryptor(aeadEncDataPacket, sessionKey);
}
@Override
public PGPDataDecryptor createDataDecryptor(SymmetricEncIntegrityPacket seipd, PGPSessionKey sessionKey)
throws PGPException {
return factory.createDataDecryptor(seipd, sessionKey);
}
@Override
public SubkeyIdentifier getSubkeyIdentifier() {
return subkey;
}
}
public static class HardwareSecurityException
extends Exception {
}
}

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// SPDX-FileCopyrightText: 2023 Paul Schaub <vanitasvitae@fsfe.org>
//
// SPDX-License-Identifier: Apache-2.0
package org.pgpainless.decryption_verification
import org.bouncycastle.bcpg.AEADEncDataPacket
import org.bouncycastle.bcpg.SymmetricEncIntegrityPacket
import org.bouncycastle.openpgp.PGPException
import org.bouncycastle.openpgp.PGPSessionKey
import org.bouncycastle.openpgp.operator.PGPDataDecryptor
import org.bouncycastle.openpgp.operator.PublicKeyDataDecryptorFactory
import org.bouncycastle.openpgp.operator.bc.BcPublicKeyDataDecryptorFactory
import org.pgpainless.key.SubkeyIdentifier
import kotlin.jvm.Throws
/**
* Enable integration of hardware-backed OpenPGP keys.
*/
class HardwareSecurity {
interface DecryptionCallback {
/**
* Delegate decryption of a Public-Key-Encrypted-Session-Key (PKESK) to an external API for dealing with
* hardware security modules such as smartcards or TPMs.
*
* If decryption fails for some reason, a subclass of the [HardwareSecurityException] is thrown.
*
* @param keyId id of the key
* @param keyAlgorithm algorithm
* @param sessionKeyData encrypted session key
*
* @return decrypted session key
* @throws HardwareSecurityException exception
*/
@Throws(HardwareSecurityException::class)
fun decryptSessionKey(keyId: Long, keyAlgorithm: Int, sessionKeyData: ByteArray): ByteArray
}
/**
* Implementation of [PublicKeyDataDecryptorFactory] which delegates decryption of encrypted session keys
* to a [DecryptionCallback].
* Users can provide such a callback to delegate decryption of messages to hardware security SDKs.
*/
class HardwareDataDecryptorFactory(
override val subkeyIdentifier: SubkeyIdentifier,
private val callback: DecryptionCallback,
) : CustomPublicKeyDataDecryptorFactory {
// luckily we can instantiate the BcPublicKeyDataDecryptorFactory with null as argument.
private val factory: PublicKeyDataDecryptorFactory = BcPublicKeyDataDecryptorFactory(null)
override fun createDataDecryptor(withIntegrityPacket: Boolean, encAlgorithm: Int, key: ByteArray?): PGPDataDecryptor {
return factory.createDataDecryptor(withIntegrityPacket, encAlgorithm, key)
}
override fun createDataDecryptor(aeadEncDataPacket: AEADEncDataPacket?, sessionKey: PGPSessionKey?): PGPDataDecryptor {
return factory.createDataDecryptor(aeadEncDataPacket, sessionKey)
}
override fun createDataDecryptor(seipd: SymmetricEncIntegrityPacket?, sessionKey: PGPSessionKey?): PGPDataDecryptor {
return factory.createDataDecryptor(seipd, sessionKey)
}
override fun recoverSessionData(keyAlgorithm: Int, secKeyData: Array<out ByteArray>): ByteArray {
return try {
callback.decryptSessionKey(subkeyIdentifier.subkeyId, keyAlgorithm, secKeyData[0])
} catch (e : HardwareSecurityException) {
throw PGPException("Hardware-backed decryption failed.", e)
}
}
}
class HardwareSecurityException : Exception()
}