使用 BouncyCastle 在 Android 上实现 ECDH 的问题

Question

我正在尝试在 Android 上实现 ECDH，并且我设法获取了测试密钥协议的代码（完整代码如下所示）

不幸的是，当我运行代码时，它给了我一个 java.security.NoSuchAlgorithmException: KeyPairGenerator ECDH 实现未找到。

正如

KeyPairGenerator    g = KeyPairGenerator.getInstance("ECDH", "BC");

我注意到的，有些人提到 Android 上不完全支持 BouncyCastle，并且不能使用我拥有的 SpongyCastle。我还尝试将提供程序从“BC”更改为“SC”

KeyPairGenerator    g = KeyPairGenerator.getInstance("ECDH", "SC");

不幸的是，这给了我一个 java.security.NoSuchProviderException: SC

希望有人能给我一些指导。非常感谢！

部分testECDH()代码：

import org.spongycastle.jce.ECPointUtil;
import org.spongycastle.jce.provider.BouncyCastleProvider;
import org.spongycastle.util.encoders.Hex;
import org.spongycastle.util.test.SimpleTest;

private void testECDH()
{
    try
    {
        KeyPairGenerator    g = KeyPairGenerator.getInstance("ECDH", "SC");

        EllipticCurve curve = new EllipticCurve(
                new ECFieldFp(new BigInteger("883423532389192164791648750360308885314476597252960362792450860609699839")), // q
                new BigInteger("7fffffffffffffffffffffff7fffffffffff8000000000007ffffffffffc", 16), // a
                new BigInteger("6b016c3bdcf18941d0d654921475ca71a9db2fb27d1d37796185c2942c0a", 16)); // b

        ECParameterSpec ecSpec = new ECParameterSpec(
                curve,
                ECPointUtil.decodePoint(curve, Hex.decode("020ffa963cdca8816ccc33b8642bedf905c3d358573d3f27fbbd3b3cb9aaaf")), // G
                new BigInteger("883423532389192164791648750360308884807550341691627752275345424702807307"), // n
                1); // h

        g.initialize(ecSpec, new SecureRandom());

        //
        // a side
        //
        KeyPair aKeyPair = g.generateKeyPair();

        KeyAgreement aKeyAgree = KeyAgreement.getInstance("ECDH", "SC");

        aKeyAgree.init(aKeyPair.getPrivate());

        //
        // b side
        //
        KeyPair bKeyPair = g.generateKeyPair();

        KeyAgreement bKeyAgree = KeyAgreement.getInstance("ECDH", "SC");

        bKeyAgree.init(bKeyPair.getPrivate());

        //
        // agreement
        //
        aKeyAgree.doPhase(bKeyPair.getPublic(), true);
        bKeyAgree.doPhase(aKeyPair.getPublic(), true);

        BigInteger  k1 = new BigInteger(aKeyAgree.generateSecret());
        BigInteger  k2 = new BigInteger(bKeyAgree.generateSecret());

        if (!k1.equals(k2))
        {
            fail("ECDH 2-way test failed");
        }

        //
        // public key encoding test
        //
        byte[]              pubEnc = aKeyPair.getPublic().getEncoded();
        KeyFactory          keyFac = KeyFactory.getInstance("ECDH", "SC");
        X509EncodedKeySpec  pubX509 = new X509EncodedKeySpec(pubEnc);
        ECPublicKey         pubKey = (ECPublicKey)keyFac.generatePublic(pubX509);

        if (!pubKey.getW().equals(((ECPublicKey)aKeyPair.getPublic()).getW()))
        {
            System.out.println(" expected " + pubKey.getW().getAffineX() + " got " + ((ECPublicKey)aKeyPair.getPublic()).getW().getAffineX());
            System.out.println(" expected " + pubKey.getW().getAffineY() + " got " + ((ECPublicKey)aKeyPair.getPublic()).getW().getAffineY());
            fail("ECDH public key encoding (W test) failed");
        }

        if (!pubKey.getParams().getGenerator().equals(((ECPublicKey)aKeyPair.getPublic()).getParams().getGenerator()))
        {
            fail("ECDH public key encoding (G test) failed");
        }

        //
        // private key encoding test
        //
        byte[]              privEnc = aKeyPair.getPrivate().getEncoded();
        PKCS8EncodedKeySpec privPKCS8 = new PKCS8EncodedKeySpec(privEnc);
        ECPrivateKey        privKey = (ECPrivateKey)keyFac.generatePrivate(privPKCS8);

        if (!privKey.getS().equals(((ECPrivateKey)aKeyPair.getPrivate()).getS()))
        {
            fail("ECDH private key encoding (S test) failed");
        }

        if (!privKey.getParams().getGenerator().equals(((ECPrivateKey)aKeyPair.getPrivate()).getParams().getGenerator()))
        {
            fail("ECDH private key encoding (G test) failed");
        }
    }
    catch (Exception e)
    {
        fail("ECDH 2-way test failed - exception: " + e);
    }
}