Example usage for java.security KeyPairGenerator getInstance

Introduction

In this page you can find the example usage for java.security KeyPairGenerator getInstance.

Prototype

public static KeyPairGenerator getInstance(String algorithm) throws NoSuchAlgorithmException

Source Link

Document

Returns a KeyPairGenerator object that generates public/private key pairs for the specified algorithm.

Usage

From source file:MainClass.java

public static void main(String args[]) throws Exception {
    KeyPairGenerator keyGen = KeyPairGenerator.getInstance("DSA");
    SecureRandom random = SecureRandom.getInstance("SHA1PRNG", "SUN");
    random.setSeed(101L);/* w  w  w  . j  av  a  2s .co  m*/
    keyGen.initialize(1024, random);
    KeyPair keypair = keyGen.generateKeyPair();

    KeyFactory kfactory = KeyFactory.getInstance("DSA");

    DSAPublicKeySpec kspec = (DSAPublicKeySpec) kfactory.getKeySpec(keypair.getPublic(),
            DSAPublicKeySpec.class);

    System.out.println(keypair.getPublic());
    FileOutputStream fos = new FileOutputStream("publicKeys");
    ObjectOutputStream oos = new ObjectOutputStream(fos);

    oos.writeObject(kspec.getY());
    oos.writeObject(kspec.getP());
    oos.writeObject(kspec.getQ());
    oos.writeObject(kspec.getG());

    FileInputStream fin = new FileInputStream("publicKeys");
    ObjectInputStream ois = new ObjectInputStream(fin);

    BigInteger Y = (BigInteger) ois.readObject();
    BigInteger P = (BigInteger) ois.readObject();
    BigInteger Q = (BigInteger) ois.readObject();
    BigInteger G = (BigInteger) ois.readObject();

    DSAPublicKeySpec keyspec = new DSAPublicKeySpec(Y, P, Q, G);
    PublicKey pkey = kfactory.generatePublic(keyspec);
    System.out.println(pkey);
}

From source file:Main.java

public static void main(String[] argv) throws Exception {
    KeyPairGenerator keyGen = KeyPairGenerator.getInstance("DSA");
    keyGen.initialize(1024);//from  ww w. j  a  v a  2 s .  c  o m
    KeyPair keypair = keyGen.genKeyPair();
    DSAPrivateKey privateKey = (DSAPrivateKey) keypair.getPrivate();
    DSAPublicKey publicKey = (DSAPublicKey) keypair.getPublic();

    DSAParams dsaParams = privateKey.getParams();
    BigInteger p = dsaParams.getP();
    BigInteger q = dsaParams.getQ();
    BigInteger g = dsaParams.getG();
    BigInteger x = privateKey.getX();
    BigInteger y = publicKey.getY();

    KeyFactory keyFactory = KeyFactory.getInstance("DSA");

}

From source file:Main.java

public static void main(String[] argv) throws Exception {
    KeyPairGenerator keyGen = KeyPairGenerator.getInstance("DSA");
    keyGen.initialize(1024);/*from w ww. java 2  s .c  om*/
    KeyPair keypair = keyGen.genKeyPair();
    DSAPrivateKey privateKey = (DSAPrivateKey) keypair.getPrivate();
    DSAPublicKey publicKey = (DSAPublicKey) keypair.getPublic();

    DSAParams dsaParams = privateKey.getParams();
    BigInteger p = dsaParams.getP();
    BigInteger q = dsaParams.getQ();
    BigInteger g = dsaParams.getG();
    BigInteger x = privateKey.getX();
    BigInteger y = publicKey.getY();

    KeyFactory keyFactory = KeyFactory.getInstance("DSA");
    KeySpec publicKeySpec = new DSAPublicKeySpec(y, p, q, g);
    PublicKey publicKey1 = keyFactory.generatePublic(publicKeySpec);
}

From source file:Main.java

public static void main(String[] argv) throws Exception {
    KeyPairGenerator keyGen = KeyPairGenerator.getInstance("DSA");
    keyGen.initialize(1024);/*from ww w. j  av a2s .c  om*/
    KeyPair keypair = keyGen.genKeyPair();
    DSAPrivateKey privateKey = (DSAPrivateKey) keypair.getPrivate();
    DSAPublicKey publicKey = (DSAPublicKey) keypair.getPublic();

    DSAParams dsaParams = privateKey.getParams();
    BigInteger p = dsaParams.getP();
    BigInteger q = dsaParams.getQ();
    BigInteger g = dsaParams.getG();
    BigInteger x = privateKey.getX();
    BigInteger y = publicKey.getY();

    KeyFactory keyFactory = KeyFactory.getInstance("DSA");
    KeySpec privateKeySpec = new DSAPrivateKeySpec(x, p, q, g);
    PrivateKey privateKey1 = keyFactory.generatePrivate(privateKeySpec);
}

From source file:Main.java

public static void main(String[] argv) throws Exception {
    KeyPairGenerator keyGen = KeyPairGenerator.getInstance("DSA");
    keyGen.initialize(1024);/* w  w  w. j a  v a2 s. com*/
    KeyPair keypair = keyGen.genKeyPair();
    DSAPrivateKey privateKey = (DSAPrivateKey) keypair.getPrivate();
    DSAPublicKey publicKey = (DSAPublicKey) keypair.getPublic();

    DSAParams dsaParams = privateKey.getParams();
    BigInteger p = dsaParams.getP();
    BigInteger q = dsaParams.getQ();
    BigInteger g = dsaParams.getG();
    BigInteger x = privateKey.getX();
    BigInteger y = publicKey.getY();

    KeyFactory keyFactory = KeyFactory.getInstance("DSA");
    KeySpec publicKeySpec = new DSAPublicKeySpec(y, p, q, g);
    PublicKey publicKey1 = keyFactory.generatePublic(publicKeySpec);
    KeySpec privateKeySpec = new DSAPrivateKeySpec(x, p, q, g);
    PrivateKey privateKey1 = keyFactory.generatePrivate(privateKeySpec);

    byte[] buffer = new byte[1024];

    Signature sig = Signature.getInstance(privateKey1.getAlgorithm());
    sig.initSign(privateKey1);
    sig.update(buffer, 0, buffer.length);

    byte[] signature = sig.sign();

    sig = Signature.getInstance(publicKey1.getAlgorithm());
    sig.initVerify(publicKey1);
    sig.update(buffer, 0, buffer.length);
    sig.verify(signature);

}

From source file:MainClass.java

public static void main(String[] args) {
    if (args.length != 2) {
        String err = "Usage: KeyGeneratorApp algorithmName keySize";
        System.out.println(err);/*from   w  w  w  .j  av a 2s  .  c o m*/
        System.exit(0);
    }
    int keySize = (new Integer(args[1])).intValue();
    SecretKey skey = null;
    KeyPair keys = null;
    String algorithm = args[0];

    try {
        KeyPairGenerator kpg = KeyPairGenerator.getInstance(algorithm);
        kpg.initialize(keySize);
        keys = kpg.genKeyPair();
    } catch (NoSuchAlgorithmException ex1) {
        try {
            KeyGenerator kg = KeyGenerator.getInstance(algorithm);
            kg.init(keySize);
            skey = kg.generateKey();
        } catch (NoSuchAlgorithmException ex2) {
            System.out.println("Algorithm not supported: " + algorithm);
            System.exit(0);

        }
    }
}

From source file:Main.java

public static void main(String[] args) throws Exception {
    KeyPairGenerator kpg = KeyPairGenerator.getInstance("DSA");
    kpg.initialize(1024, new SecureRandom());
    KeyPair dsaKeyPair = kpg.generateKeyPair();

    XMLSignatureFactory sigFactory = XMLSignatureFactory.getInstance();
    Reference ref = sigFactory.newReference("#Body", sigFactory.newDigestMethod(DigestMethod.SHA1, null));
    SignedInfo signedInfo = sigFactory.newSignedInfo(
            sigFactory.newCanonicalizationMethod(CanonicalizationMethod.INCLUSIVE_WITH_COMMENTS,
                    (C14NMethodParameterSpec) null),
            sigFactory.newSignatureMethod(SignatureMethod.DSA_SHA1, null), Collections.singletonList(ref));
    KeyInfoFactory kif = sigFactory.getKeyInfoFactory();
    KeyValue kv = kif.newKeyValue(dsaKeyPair.getPublic());
    KeyInfo keyInfo = kif.newKeyInfo(Collections.singletonList(kv));

    XMLSignature xmlSig = sigFactory.newXMLSignature(signedInfo, keyInfo);
}

From source file:MainClass.java

public static void main(String[] args) throws Exception {

    KeyPairGenerator kpg = KeyPairGenerator.getInstance("DSA");
    kpg.initialize(1024, new SecureRandom());
    KeyPair dsaKeyPair = kpg.generateKeyPair();

    XMLSignatureFactory sigFactory = XMLSignatureFactory.getInstance();
    Reference ref = sigFactory.newReference("#Body", sigFactory.newDigestMethod(DigestMethod.SHA1, null));
    SignedInfo signedInfo = sigFactory.newSignedInfo(
            sigFactory.newCanonicalizationMethod(CanonicalizationMethod.INCLUSIVE_WITH_COMMENTS,
                    (C14NMethodParameterSpec) null),
            sigFactory.newSignatureMethod(SignatureMethod.DSA_SHA1, null), Collections.singletonList(ref));
    KeyInfoFactory kif = sigFactory.getKeyInfoFactory();
    KeyValue kv = kif.newKeyValue(dsaKeyPair.getPublic());
    KeyInfo keyInfo = kif.newKeyInfo(Collections.singletonList(kv));

    XMLSignature xmlSig = sigFactory.newXMLSignature(signedInfo, keyInfo);
}

From source file:KeyTools.java

public static void main(String[] rgstring) {
    try {//from   ww w .  j  a v a  2  s  .com
        File filePublic = new File(rgstring[0]);
        File filePrivate = new File(rgstring[1]);

        KeyPairGenerator keypairgenerator = KeyPairGenerator.getInstance("DSA");

        keypairgenerator.initialize(1024, new SecureRandom());

        KeyPair keypair = keypairgenerator.generateKeyPair();

        writeToFile(keypair.getPublic(), filePublic);
        writeToFile(keypair.getPrivate(), filePrivate);
    } catch (Exception ex) {
        ex.printStackTrace();
    }
}

From source file:MainClass.java

public static void main(String[] args) throws Exception {
    String s = "F488FD584E49DBCD20B49DE49107366B336C380D451D0F7C88"
            + "11111111111111111111111111111111111111111111111111"
            + "11111111111111111111111111111111111111111111111111"
            + "11111111111111111111111111111111111111111111111111"
            + "11111111111111111111111111111111111111111111111111" + "2F78C7";
    BigInteger base = BigInteger.valueOf(2);
    BigInteger modulus = new BigInteger(s, 16);
    DHParameterSpec skipParameterSpec = new DHParameterSpec(modulus, base);

    KeyPairGenerator kpg1 = KeyPairGenerator.getInstance("DH");
    kpg1.initialize(skipParameterSpec);//  w w w  .j  av  a2 s. c om
    KeyPair kp1 = kpg1.generateKeyPair();

    KeyAgreement ka1 = KeyAgreement.getInstance("DH");
    DHPrivateKey privateKey1 = (DHPrivateKey) kp1.getPrivate();
    DHPublicKey publicKey1 = (DHPublicKey) kp1.getPublic();
    ka1.init(privateKey1);
    System.out.println("1 is using " + publicKey1.getY() + " for its public key");
    KeyPairGenerator kpg2 = KeyPairGenerator.getInstance("DH");
    kpg2.initialize(skipParameterSpec);
    KeyPair kp2 = kpg2.generateKeyPair();

    KeyAgreement ka2 = KeyAgreement.getInstance("DH");
    DHPrivateKey privateKey2 = (DHPrivateKey) kp2.getPrivate();
    DHPublicKey publicKey2 = (DHPublicKey) kp2.getPublic();
    ka2.init(privateKey2);
    System.out.println("2 is using " + publicKey2.getY() + " for its public key");
    ka1.doPhase(publicKey2, true);
    byte[] sharedKey1 = ka1.generateSecret();
    System.out.println("1 is using " + new BigInteger(1, sharedKey1) + " for its shared key");

    ka2.doPhase(publicKey1, true);
    byte[] sharedKey2 = ka2.generateSecret();
    System.out.println("2 is using " + new BigInteger(1, sharedKey2) + " for its shared key");
}