1/*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package org.conscrypt;
18
19import java.math.BigInteger;
20import java.security.InvalidAlgorithmParameterException;
21import java.security.KeyPair;
22import java.security.KeyPairGeneratorSpi;
23import java.security.SecureRandom;
24import java.security.spec.AlgorithmParameterSpec;
25import java.security.spec.DSAParameterSpec;
26
27public class OpenSSLDSAKeyPairGenerator extends KeyPairGeneratorSpi {
28
29    private int primeBits = 1024;
30
31    private SecureRandom random = null;
32
33    private byte[] g;
34
35    private byte[] p;
36
37    private byte[] q;
38
39    @Override
40    public KeyPair generateKeyPair() {
41        final byte[] seed;
42        if (random == null) {
43            seed = null;
44        } else {
45            seed = new byte[20];
46            random.nextBytes(seed);
47        }
48
49        final OpenSSLKey key = new OpenSSLKey(NativeCrypto.DSA_generate_key(primeBits, seed, g, p,
50                q));
51
52        final OpenSSLDSAPrivateKey privKey = new OpenSSLDSAPrivateKey(key);
53        final OpenSSLDSAPublicKey pubKey = new OpenSSLDSAPublicKey(key);
54
55        return new KeyPair(pubKey, privKey);
56    }
57
58    @Override
59    public void initialize(int keysize, SecureRandom random) {
60        primeBits = keysize;
61        this.random = random;
62    }
63
64    @Override
65    public void initialize(AlgorithmParameterSpec params, SecureRandom random)
66            throws InvalidAlgorithmParameterException {
67        this.random = random;
68
69        if (params instanceof DSAParameterSpec) {
70            DSAParameterSpec dsaParams = (DSAParameterSpec) params;
71
72            BigInteger gInt = dsaParams.getG();
73            if (gInt != null) {
74                g = gInt.toByteArray();
75            }
76
77            BigInteger pInt = dsaParams.getP();
78            if (pInt != null) {
79                p = pInt.toByteArray();
80            }
81
82            BigInteger qInt = dsaParams.getQ();
83            if (qInt != null) {
84                q = qInt.toByteArray();
85            }
86        } else if (params != null) {
87            throw new InvalidAlgorithmParameterException("Params must be DSAParameterSpec");
88        }
89    }
90}
91