| /* |
| * Copyright (c) 2009, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package sun.security.ec; |
| |
| import java.math.BigInteger; |
| import java.security.*; |
| import java.security.spec.AlgorithmParameterSpec; |
| import java.security.spec.ECGenParameterSpec; |
| import java.security.spec.ECParameterSpec; |
| import java.security.spec.ECPoint; |
| |
| import sun.security.ec.NamedCurve; |
| import sun.security.ec.ECParameters; |
| import sun.security.ec.ECPrivateKeyImpl; |
| import sun.security.ec.ECPublicKeyImpl; |
| import sun.security.jca.JCAUtil; |
| |
| /** |
| * EC keypair generator. |
| * Standard algorithm, minimum key length is 112 bits, maximum is 571 bits. |
| * |
| * @since 1.7 |
| */ |
| public final class ECKeyPairGenerator extends KeyPairGeneratorSpi { |
| |
| private static final int KEY_SIZE_MIN = 112; // min bits (see ecc_impl.h) |
| private static final int KEY_SIZE_MAX = 571; // max bits (see ecc_impl.h) |
| private static final int KEY_SIZE_DEFAULT = 256; |
| |
| // used to seed the keypair generator |
| private SecureRandom random; |
| |
| // size of the key to generate, KEY_SIZE_MIN <= keySize <= KEY_SIZE_MAX |
| private int keySize; |
| |
| // parameters specified via init, if any |
| private AlgorithmParameterSpec params = null; |
| |
| /** |
| * Constructs a new ECKeyPairGenerator. |
| */ |
| public ECKeyPairGenerator() { |
| // initialize to default in case the app does not call initialize() |
| initialize(KEY_SIZE_DEFAULT, null); |
| } |
| |
| // initialize the generator. See JCA doc |
| @Override |
| public void initialize(int keySize, SecureRandom random) { |
| |
| checkKeySize(keySize); |
| this.params = NamedCurve.getECParameterSpec(keySize); |
| if (params == null) { |
| throw new InvalidParameterException( |
| "No EC parameters available for key size " + keySize + " bits"); |
| } |
| this.random = random; |
| } |
| |
| // second initialize method. See JCA doc |
| @Override |
| public void initialize(AlgorithmParameterSpec params, SecureRandom random) |
| throws InvalidAlgorithmParameterException { |
| |
| if (params instanceof ECParameterSpec) { |
| this.params = ECParameters.getNamedCurve((ECParameterSpec)params); |
| if (this.params == null) { |
| throw new InvalidAlgorithmParameterException( |
| "Unsupported curve: " + params); |
| } |
| } else if (params instanceof ECGenParameterSpec) { |
| String name = ((ECGenParameterSpec)params).getName(); |
| this.params = NamedCurve.getECParameterSpec(name); |
| if (this.params == null) { |
| throw new InvalidAlgorithmParameterException( |
| "Unknown curve name: " + name); |
| } |
| } else { |
| throw new InvalidAlgorithmParameterException( |
| "ECParameterSpec or ECGenParameterSpec required for EC"); |
| } |
| this.keySize = |
| ((ECParameterSpec)this.params).getCurve().getField().getFieldSize(); |
| this.random = random; |
| } |
| |
| // generate the keypair. See JCA doc |
| @Override |
| public KeyPair generateKeyPair() { |
| |
| byte[] encodedParams = |
| ECParameters.encodeParameters((ECParameterSpec)params); |
| |
| // seed is twice the key size (in bytes) plus 1 |
| byte[] seed = new byte[(((keySize + 7) >> 3) + 1) * 2]; |
| if (random == null) { |
| random = JCAUtil.getSecureRandom(); |
| } |
| random.nextBytes(seed); |
| |
| long[] handles = generateECKeyPair(keySize, encodedParams, seed); |
| |
| // The 'params' object supplied above is equivalent to the native one |
| // so there is no need to fetch it. |
| |
| // handles[0] points to the native private key |
| BigInteger s = new BigInteger(1, getEncodedBytes(handles[0])); |
| |
| try { |
| PrivateKey privateKey = |
| new ECPrivateKeyImpl(s, (ECParameterSpec)params); |
| |
| // handles[1] points to the native public key |
| ECPoint w = ECParameters.decodePoint(getEncodedBytes(handles[1]), |
| ((ECParameterSpec)params).getCurve()); |
| PublicKey publicKey = |
| new ECPublicKeyImpl(w, (ECParameterSpec)params); |
| |
| return new KeyPair(publicKey, privateKey); |
| |
| } catch (Exception e) { |
| throw new ProviderException(e); |
| } |
| } |
| |
| private void checkKeySize(int keySize) throws InvalidParameterException { |
| if (keySize < KEY_SIZE_MIN) { |
| throw new InvalidParameterException |
| ("Key size must be at least " + KEY_SIZE_MIN + " bits"); |
| } |
| if (keySize > KEY_SIZE_MAX) { |
| throw new InvalidParameterException |
| ("Key size must be at most " + KEY_SIZE_MAX + " bits"); |
| } |
| this.keySize = keySize; |
| } |
| |
| /* |
| * Generates the keypair and returns a 2-element array of handles. |
| * The first handle points to the private key, the second to the public key. |
| */ |
| private static native long[] generateECKeyPair(int keySize, |
| byte[] encodedParams, byte[] seed); |
| |
| /* |
| * Extracts the encoded key data using the supplied handle. |
| */ |
| private static native byte[] getEncodedBytes(long handle); |
| } |