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:Main.java

public static void main(String[] argv) throws Exception {
    String algorithm = "DSA"; // or RSA, DH, etc.

    // Generate a 1024-bit Digital Signature Algorithm (DSA) key pair
    KeyPairGenerator keyGen = KeyPairGenerator.getInstance(algorithm);
    keyGen.initialize(1024);// w w  w .  j  av a  2  s  .c  om
    KeyPair keypair = keyGen.genKeyPair();
    PrivateKey privateKey = keypair.getPrivate();
    PublicKey publicKey = keypair.getPublic();
}

From source file:Main.java

public static void main(String[] argv) throws Exception {
    String algorithm = "DSA"; // or RSA, DH, etc.

    // Generate a 1024-bit Digital Signature Algorithm (DSA) key pair
    KeyPairGenerator keyGen = KeyPairGenerator.getInstance(algorithm);
    keyGen.initialize(1024);//from w w  w  .j a va 2s .c  o m
    KeyPair keypair = keyGen.genKeyPair();
    PrivateKey privateKey = keypair.getPrivate();
    PublicKey publicKey = keypair.getPublic();
    String format = privateKey.getFormat(); // PKCS#8
    format = publicKey.getFormat(); // X.509
}

From source file:Main.java

public static void main(String[] argv) throws Exception {
    String algorithm = "DSA"; // or RSA, DH, etc.

    // Generate a 1024-bit Digital Signature Algorithm (DSA) key pair
    KeyPairGenerator keyGen = KeyPairGenerator.getInstance(algorithm);
    keyGen.initialize(1024);//from  ww w  . j a v a2  s.c  o  m
    KeyPair keypair = keyGen.genKeyPair();
    PrivateKey privateKey = keypair.getPrivate();
    PublicKey publicKey = keypair.getPublic();

    byte[] privateKeyBytes = privateKey.getEncoded();
    byte[] publicKeyBytes = publicKey.getEncoded();
}

From source file:cn.lynx.emi.license.GenerateKeyPairs.java

public static void main(String[] args) throws NoSuchAlgorithmException {
    KeyPairGenerator keygen = KeyPairGenerator.getInstance("RSA");
    SecureRandom secrand = new SecureRandom();
    secrand.setSeed("cn.lynx.emi".getBytes());
    keygen.initialize(4096, secrand);/*w  ww.j a  v  a  2 s  .  com*/
    KeyPair keys = keygen.genKeyPair();

    PublicKey pubkey = keys.getPublic();
    PrivateKey prikey = keys.getPrivate();

    String myPubKey = Base64.encodeBase64String(pubkey.getEncoded());
    String myPriKey = Base64.encodeBase64String(prikey.getEncoded());
    System.out.println(prikey);
    System.out.println("pubKey=" + myPubKey);
    System.out.println("priKey=" + myPriKey);
}

From source file:MainClass.java

public static void main(String[] args) throws Exception {
    int eValue = 79;
    int bitLength = 1024; // KeySize

    BigInteger e = e = new BigInteger(Integer.toString(eValue));

    KeyPairGenerator kpg = KeyPairGenerator.getInstance("RSA");
    kpg.initialize(bitLength);/* www.j a v  a 2 s .  c  o m*/
    KeyPair kp = kpg.generateKeyPair();

    KeyFactory kfactory = KeyFactory.getInstance("RSA");
    RSAPublicKeySpec kspec = (RSAPublicKeySpec) kfactory.getKeySpec(kp.getPublic(), RSAPublicKeySpec.class);

    kpg = KeyPairGenerator.getInstance("RSA", "SunRsaSign");

    e = new BigInteger(Integer.toString(eValue));
    System.out.println("e =" + e);
    RSAKeyGenParameterSpec param = new RSAKeyGenParameterSpec(bitLength, e);
    kpg.initialize(param);
    kp = kpg.generateKeyPair();

    kfactory = KeyFactory.getInstance("RSA", "SunRsaSign");

    kspec = (RSAPublicKeySpec) kfactory.getKeySpec(kp.getPublic(), RSAPublicKeySpec.class);
}

From source file:MainClass.java

public static void main(String[] args) throws NoSuchAlgorithmException, InvalidKeySpecException {
    KeyPairGenerator kpg = KeyPairGenerator.getInstance("DSA");
    kpg.initialize(512);/*w  w  w . jav  a2 s  . c o m*/
    KeyPair keys = kpg.genKeyPair();
    PrivateKey priKey = keys.getPrivate();
    PublicKey pubKey = keys.getPublic();
    KeyFactory kf = KeyFactory.getInstance("DSA");
    DSAPrivateKeySpec dsaPriKeySpec = (DSAPrivateKeySpec) kf.getKeySpec(priKey, DSAPrivateKeySpec.class);
    DSAPublicKeySpec dsaPubKeySpec = (DSAPublicKeySpec) kf.getKeySpec(pubKey, DSAPublicKeySpec.class);
    System.out.println("\nDSA Private Key");
    System.out.println("\nx = " + dsaPriKeySpec.getX());
    System.out.println("\nDSA Public Key");
    System.out.println("\ng = " + dsaPubKeySpec.getG());
    System.out.println("\np = " + dsaPubKeySpec.getP());
    System.out.println("\nq = " + dsaPubKeySpec.getQ());
    System.out.println("\ny = " + dsaPubKeySpec.getY());
}

From source file:MainClass.java

public static void main(String[] args) throws Exception {
    KeyGenerator keyGenerator = KeyGenerator.getInstance("Blowfish");
    keyGenerator.init(128);//from w w  w. j  av a  2s.  c o  m
    Key blowfishKey = keyGenerator.generateKey();

    KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
    keyPairGenerator.initialize(1024);
    KeyPair keyPair = keyPairGenerator.genKeyPair();

    Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
    cipher.init(Cipher.ENCRYPT_MODE, keyPair.getPublic());

    byte[] blowfishKeyBytes = blowfishKey.getEncoded();
    System.out.println(new String(blowfishKeyBytes));
    byte[] cipherText = cipher.doFinal(blowfishKeyBytes);
    System.out.println(new String(cipherText));
    cipher.init(Cipher.DECRYPT_MODE, keyPair.getPrivate());

    byte[] decryptedKeyBytes = cipher.doFinal(cipherText);
    System.out.println(new String(decryptedKeyBytes));
    SecretKey newBlowfishKey = new SecretKeySpec(decryptedKeyBytes, "Blowfish");
}

From source file:Main.java

public static void main(String[] argv) throws Exception {
    KeyPairGenerator keyGen = KeyPairGenerator.getInstance("DSA");
    keyGen.initialize(1024);//from   w w w.j a va  2s  .  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();

    // Create the DSA key factory
    KeyFactory keyFactory = KeyFactory.getInstance("DSA");
    // Create the DSA private key
    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);
}

From source file:MainClass.java

public static void main(String[] args) throws Exception {
    String password = "password";

    KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
    keyPairGenerator.initialize(1024);//ww w . j a v  a2 s  . c o m
    KeyPair keyPair = keyPairGenerator.genKeyPair();
    String publicKeyFilename = "public";

    byte[] publicKeyBytes = keyPair.getPublic().getEncoded();

    FileOutputStream fos = new FileOutputStream(publicKeyFilename);
    fos.write(publicKeyBytes);
    fos.close();

    String privateKeyFilename = "privateKeyFilename";

    byte[] privateKeyBytes = keyPair.getPrivate().getEncoded();

    byte[] encryptedPrivateKeyBytes = passwordEncrypt(password.toCharArray(), privateKeyBytes);

    fos = new FileOutputStream(privateKeyFilename);
    fos.write(encryptedPrivateKeyBytes);
    fos.close();
}

From source file:Main.java

public static void main(String[] argv) throws Exception {
    String algorithm = "DSA"; // or RSA, DH, etc.

    // Generate a 1024-bit Digital Signature Algorithm (DSA) key pair
    KeyPairGenerator keyGen = KeyPairGenerator.getInstance(algorithm);
    keyGen.initialize(1024);/*from   w ww. j  a v a2 s  .c  o m*/
    KeyPair keypair = keyGen.genKeyPair();
    PrivateKey privateKey = keypair.getPrivate();
    PublicKey publicKey = keypair.getPublic();

    byte[] privateKeyBytes = privateKey.getEncoded();
    byte[] publicKeyBytes = publicKey.getEncoded();

    KeyFactory keyFactory = KeyFactory.getInstance(algorithm);
    EncodedKeySpec privateKeySpec = new PKCS8EncodedKeySpec(privateKeyBytes);
    PrivateKey privateKey2 = keyFactory.generatePrivate(privateKeySpec);

    EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(publicKeyBytes);
    PublicKey publicKey2 = keyFactory.generatePublic(publicKeySpec);

    // The orginal and new keys are the same
    boolean same = privateKey.equals(privateKey2);
    same = publicKey.equals(publicKey2);
}