Example usage for java.security SecureRandom SecureRandom

List of usage examples for java.security SecureRandom SecureRandom

  1. HOME
  2. Java
  3. java
  4. java.security.*
  5. SecureRandom
  6. SecureRandom

Introduction

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

Prototype

public SecureRandom()

Source Link

Document

Constructs a secure random number generator (RNG) implementing the default random number algorithm.

Usage

From source file:MainClass.java

public static void main(String[] args) throws Exception {
    Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

    byte[] input = "abc".getBytes();
    Cipher cipher = Cipher.getInstance("RSA/None/OAEPWithSHA1AndMGF1Padding", "BC");
    SecureRandom random = new SecureRandom();
    KeyPairGenerator generator = KeyPairGenerator.getInstance("RSA", "BC");

    generator.initialize(386, random);//from  www.  j a  va2 s .  c  om

    KeyPair pair = generator.generateKeyPair();
    Key pubKey = pair.getPublic();

    Key privKey = pair.getPrivate();

    cipher.init(Cipher.ENCRYPT_MODE, pubKey, random);
    byte[] cipherText = cipher.doFinal(input);
    System.out.println("cipher: " + new String(cipherText));

    cipher.init(Cipher.DECRYPT_MODE, privKey);
    byte[] plainText = cipher.doFinal(cipherText);
    System.out.println("plain : " + new String(plainText));
}

From source file:MainClass.java

public static void main(String args[]) throws Exception {
    KeyGenerator kg = KeyGenerator.getInstance("DES");
    kg.init(new SecureRandom());
    SecretKey key = kg.generateKey();
    SecretKeyFactory skf = SecretKeyFactory.getInstance("DES");
    Class spec = Class.forName("javax.crypto.spec.DESKeySpec");
    DESKeySpec ks = (DESKeySpec) skf.getKeySpec(key, spec);
    ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("keyfile"));
    oos.writeObject(ks.getKey());//from  w  ww  .  ja  v  a 2 s.  com

    Cipher c = Cipher.getInstance("DES/CFB8/NoPadding");
    c.init(Cipher.ENCRYPT_MODE, key);
    CipherOutputStream cos = new CipherOutputStream(new FileOutputStream("ciphertext"), c);
    PrintWriter pw = new PrintWriter(new OutputStreamWriter(cos));
    pw.println("Stand and unfold yourself");
    pw.close();
    oos.writeObject(c.getIV());
    oos.close();
}

From source file:Main.java

public static void main(String[] args) throws Exception {
    //Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

    byte[] input = "ab".getBytes();
    Cipher cipher = Cipher.getInstance("ElGamal/None/NoPadding", "BC");
    KeyPairGenerator generator = KeyPairGenerator.getInstance("ElGamal", "BC");
    SecureRandom random = new SecureRandom();

    generator.initialize(128, random);/*from   w ww .  j  a v a  2s .  c  o  m*/

    KeyPair pair = generator.generateKeyPair();
    Key pubKey = pair.getPublic();
    Key privKey = pair.getPrivate();
    cipher.init(Cipher.ENCRYPT_MODE, pubKey, random);
    byte[] cipherText = cipher.doFinal(input);
    System.out.println("cipher: " + new String(cipherText));

    cipher.init(Cipher.DECRYPT_MODE, privKey);
    byte[] plainText = cipher.doFinal(cipherText);
    System.out.println("plain : " + new String(plainText));
}

From source file:MainClass.java

public static void main(String[] args) throws Exception {
    Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

    byte[] input = "ab".getBytes();
    Cipher cipher = Cipher.getInstance("ElGamal/None/NoPadding", "BC");
    KeyPairGenerator generator = KeyPairGenerator.getInstance("ElGamal", "BC");
    SecureRandom random = new SecureRandom();

    generator.initialize(128, random);// w  w w.  j a v a  2s.com

    KeyPair pair = generator.generateKeyPair();
    Key pubKey = pair.getPublic();
    Key privKey = pair.getPrivate();
    cipher.init(Cipher.ENCRYPT_MODE, pubKey, random);
    byte[] cipherText = cipher.doFinal(input);
    System.out.println("cipher: " + new String(cipherText));

    cipher.init(Cipher.DECRYPT_MODE, privKey);
    byte[] plainText = cipher.doFinal(cipherText);
    System.out.println("plain : " + new String(plainText));
}

From source file:MainClass.java

public static void main(String[] args) throws Exception {
    Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

    Cipher cipher = Cipher.getInstance("AES/ECB/PKCS7Padding", "BC");
    SecureRandom random = new SecureRandom();

    KeyPairGenerator fact = KeyPairGenerator.getInstance("RSA", "BC");
    fact.initialize(1024, random);/* ww  w  .  j  ava  2s  .  c  o  m*/

    KeyPair keyPair = fact.generateKeyPair();
    Key wrapKey = createKeyForAES(256, random);
    cipher.init(Cipher.WRAP_MODE, wrapKey);

    byte[] wrappedKey = cipher.wrap(keyPair.getPrivate());
    cipher.init(Cipher.UNWRAP_MODE, wrapKey);
    Key key = cipher.unwrap(wrappedKey, "RSA", Cipher.PRIVATE_KEY);
    System.out.println(keyPair.getPrivate().equals(key));

}

From source file:MainClass.java

public static void main(String[] args) throws Exception {
    Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

    SecureRandom random = new SecureRandom();
    IvParameterSpec ivSpec = createCtrIvForAES();
    Key key = createKeyForAES(256, random);
    Cipher cipher = Cipher.getInstance("AES/CTR/NoPadding", "BC");
    String input = "12345678";
    Mac mac = Mac.getInstance("DES", "BC");
    byte[] macKeyBytes = new byte[] { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
    Key macKey = new SecretKeySpec(macKeyBytes, "DES");

    cipher.init(Cipher.ENCRYPT_MODE, key, ivSpec);

    byte[] cipherText = new byte[cipher.getOutputSize(input.length() + mac.getMacLength())];

    int ctLength = cipher.update(input.getBytes(), 0, input.length(), cipherText, 0);

    mac.init(macKey);/*from  w ww  . j a v  a  2 s .  c om*/
    mac.update(input.getBytes());

    ctLength += cipher.doFinal(mac.doFinal(), 0, mac.getMacLength(), cipherText, ctLength);

    cipher.init(Cipher.DECRYPT_MODE, key, ivSpec);

    byte[] plainText = cipher.doFinal(cipherText, 0, ctLength);
    int messageLength = plainText.length - mac.getMacLength();

    mac.init(macKey);
    mac.update(plainText, 0, messageLength);

    byte[] messageHash = new byte[mac.getMacLength()];
    System.arraycopy(plainText, messageLength, messageHash, 0, messageHash.length);

    System.out.println("plain : " + new String(plainText) + " verified: "
            + MessageDigest.isEqual(mac.doFinal(), messageHash));

}

From source file:MainClass.java

public static void main(String[] args) throws Exception {
    Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
    KeyPairGenerator generator = KeyPairGenerator.getInstance("RSA", "BC");

    generator.initialize(128, new SecureRandom());
    KeyPair pair = generator.generateKeyPair();
    ASN1InputStream aIn = new ASN1InputStream(pair.getPublic().getEncoded());
    SubjectPublicKeyInfo info = SubjectPublicKeyInfo.getInstance(aIn.readObject());

    System.out.println(ASN1Dump.dumpAsString(info));
    System.out.println(ASN1Dump.dumpAsString(info.getPublicKey()));

    X509EncodedKeySpec x509Spec = new X509EncodedKeySpec(pair.getPublic().getEncoded());
    KeyFactory keyFact = KeyFactory.getInstance("RSA", "BC");
    PublicKey pubKey = keyFact.generatePublic(x509Spec);

    System.out.println(pubKey.equals(pair.getPublic()));
}

From source file:MainClass.java

public static void main(String[] args) throws Exception {
    Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

    KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA", "BC");
    keyGen.initialize(512, new SecureRandom());
    KeyPair keyPair = keyGen.generateKeyPair();

    Signature signature = Signature.getInstance("SHA256withRSA", "BC");
    signature.initSign(keyPair.getPrivate());

    byte[] message = "abc".getBytes();
    signature.update(message);/*  w  ww  .  jav a  2 s .  c o  m*/

    byte[] sigBytes = signature.sign();
    Cipher cipher = Cipher.getInstance("RSA/None/PKCS1Padding", "BC");
    cipher.init(Cipher.DECRYPT_MODE, keyPair.getPublic());

    byte[] decSig = cipher.doFinal(sigBytes);
    ASN1InputStream aIn = new ASN1InputStream(decSig);
    ASN1Sequence seq = (ASN1Sequence) aIn.readObject();

    System.out.println(ASN1Dump.dumpAsString(seq));

    MessageDigest hash = MessageDigest.getInstance("SHA-256", "BC");
    hash.update(message);

    ASN1OctetString sigHash = (ASN1OctetString) seq.getObjectAt(1);
    System.out.println(MessageDigest.isEqual(hash.digest(), sigHash.getOctets()));
}

From source file:Main.java

public static void main(String[] args) throws Exception {
    //Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

    DHParameterSpec dhParams = new DHParameterSpec(p512, g512);
    KeyPairGenerator keyGen = KeyPairGenerator.getInstance("DH", "BC");

    keyGen.initialize(dhParams, new SecureRandom());

    KeyAgreement aKeyAgree = KeyAgreement.getInstance("DH", "BC");
    KeyPair aPair = keyGen.generateKeyPair();
    KeyAgreement bKeyAgree = KeyAgreement.getInstance("DH", "BC");
    KeyPair bPair = keyGen.generateKeyPair();

    aKeyAgree.init(aPair.getPrivate());//from w  w w.j  ava2 s  .  c om
    bKeyAgree.init(bPair.getPrivate());

    aKeyAgree.doPhase(bPair.getPublic(), true);
    bKeyAgree.doPhase(aPair.getPublic(), true);

    MessageDigest hash = MessageDigest.getInstance("SHA1", "BC");
    System.out.println(new String(hash.digest(aKeyAgree.generateSecret())));
    System.out.println(new String(hash.digest(bKeyAgree.generateSecret())));
}

From source file:MainClass.java

public static void main(String[] args) throws Exception {
    Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

    DHParameterSpec dhParams = new DHParameterSpec(p512, g512);
    KeyPairGenerator keyGen = KeyPairGenerator.getInstance("DH", "BC");

    keyGen.initialize(dhParams, new SecureRandom());

    KeyAgreement aKeyAgree = KeyAgreement.getInstance("DH", "BC");
    KeyPair aPair = keyGen.generateKeyPair();
    KeyAgreement bKeyAgree = KeyAgreement.getInstance("DH", "BC");
    KeyPair bPair = keyGen.generateKeyPair();

    aKeyAgree.init(aPair.getPrivate());//from   w w  w .  j  a  v  a 2s. co  m
    bKeyAgree.init(bPair.getPrivate());

    aKeyAgree.doPhase(bPair.getPublic(), true);
    bKeyAgree.doPhase(aPair.getPublic(), true);

    MessageDigest hash = MessageDigest.getInstance("SHA1", "BC");
    System.out.println(new String(hash.digest(aKeyAgree.generateSecret())));
    System.out.println(new String(hash.digest(bKeyAgree.generateSecret())));
}