wireguard-android/app/src/main/java/com/wireguard/crypto/Keypair.java
Jason A. Donenfeld 7b28d51cdd global: move to Apache 2.0
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-07-06 16:28:46 +02:00

57 lines
1.5 KiB
Java

/*
* Copyright © 2018 Samuel Holland <samuel@sholland.org>
* Copyright © 2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
* SPDX-License-Identifier: Apache-2.0
*/
package com.wireguard.crypto;
import java.security.SecureRandom;
/**
* Represents a Curve25519 keypair as used by WireGuard.
*/
public class Keypair {
private final byte[] privateKey;
private final byte[] publicKey;
public Keypair() {
this(generatePrivateKey());
}
private Keypair(final byte[] privateKey) {
this.privateKey = privateKey;
publicKey = generatePublicKey(privateKey);
}
public Keypair(final String privateKey) {
this(KeyEncoding.keyFromBase64(privateKey));
}
@SuppressWarnings("MagicNumber")
private static byte[] generatePrivateKey() {
final SecureRandom secureRandom = new SecureRandom();
final byte[] privateKey = new byte[KeyEncoding.KEY_LENGTH];
secureRandom.nextBytes(privateKey);
privateKey[0] &= 248;
privateKey[31] &= 127;
privateKey[31] |= 64;
return privateKey;
}
private static byte[] generatePublicKey(final byte[] privateKey) {
final byte[] publicKey = new byte[KeyEncoding.KEY_LENGTH];
Curve25519.eval(publicKey, 0, privateKey, null);
return publicKey;
}
public String getPrivateKey() {
return KeyEncoding.keyToBase64(privateKey);
}
public String getPublicKey() {
return KeyEncoding.keyToBase64(publicKey);
}
}