Example usage for javax.crypto Cipher DECRYPT_MODE

List of usage examples for javax.crypto Cipher DECRYPT_MODE

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Introduction

In this page you can find the example usage for javax.crypto Cipher DECRYPT_MODE.

Prototype

int DECRYPT_MODE

To view the source code for javax.crypto Cipher DECRYPT_MODE.

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Document

Constant used to initialize cipher to decryption mode.

Usage

From source file:MainClass.java

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

    byte[] input = "input".getBytes();
    byte[] keyBytes = "input123".getBytes();

    SecretKeySpec key = new SecretKeySpec(keyBytes, "ARC4");

    Cipher cipher = Cipher.getInstance("ARC4", "BC");

    byte[] cipherText = new byte[input.length];

    cipher.init(Cipher.ENCRYPT_MODE, key);

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

    ctLength += cipher.doFinal(cipherText, ctLength);

    System.out.println("cipher text: " + new String(cipherText));

    byte[] plainText = new byte[ctLength];

    cipher.init(Cipher.DECRYPT_MODE, key);

    int ptLength = cipher.update(cipherText, 0, ctLength, plainText, 0);

    ptLength += cipher.doFinal(plainText, ptLength);

    System.out.println("plain text : " + 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 = "input".getBytes();
    byte[] keyBytes = new byte[] { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c,
            0x0d, 0x0e, 0x0f };//from  w w w .j a  v  a2 s. c o  m

    SecretKeySpec key = new SecretKeySpec(keyBytes, "AES");

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

    cipher.init(Cipher.ENCRYPT_MODE, key);

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

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

    ctLength += cipher.doFinal(cipherText, ctLength);

    cipher.init(Cipher.DECRYPT_MODE, key);
    byte[] plainText = new byte[cipher.getOutputSize(ctLength)];
    int ptLength = cipher.update(cipherText, 0, ctLength, plainText, 0);
    ptLength += cipher.doFinal(plainText, ptLength);
    System.out.println("plain : " + new String(plainText));
}

From source file:MainClass.java

public static void main(String[] args) throws Exception {
    Provider p = Security.getProvider("Rot13Provider");
    System.out.println("Provider name: " + p.getName());
    System.out.println("Provider version: " + p.getVersion());
    System.out.println("Provider information: " + p.getInfo());

    Cipher cipher = Cipher.getInstance("ROT13", "Rot13Provider");
    System.out.println("Cipher: " + cipher.getAlgorithm());
    String testString = "This is a test!";
    cipher.init(Cipher.ENCRYPT_MODE, (Key) null, new SecureRandom());
    byte[] b1 = cipher.doFinal(testString.getBytes());
    cipher.init(Cipher.DECRYPT_MODE, (Key) null, new SecureRandom());
    byte[] b2 = cipher.doFinal(b1);
    System.out.println("Decrypted data as a String: " + new String(b2));
}

From source file:MainClass.java

public static void main(String args[]) throws Exception {
    Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
    SecretKey key = KeyGenerator.getInstance("DES").generateKey();

    // for CBC; must be 8 bytes
    byte[] initVector = new byte[] { 0x10, 0x10, 0x01, 0x04, 0x01, 0x01, 0x01, 0x02 };

    AlgorithmParameterSpec algParamSpec = new IvParameterSpec(initVector);
    Cipher m_encrypter = Cipher.getInstance("DES/CBC/PKCS5Padding");
    Cipher m_decrypter = Cipher.getInstance("DES/CBC/PKCS5Padding");

    m_encrypter.init(Cipher.ENCRYPT_MODE, key, algParamSpec);
    m_decrypter.init(Cipher.DECRYPT_MODE, key, algParamSpec);

    byte[] clearText = "www.java2s.com".getBytes();

    byte[] encryptedText = m_encrypter.doFinal(clearText);

    byte[] decryptedText = m_decrypter.doFinal(encryptedText);

    System.out.println(new String(clearText));
    System.out.println(new String(encryptedText));
    System.out.println(new String(decryptedText));

}

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  . jav  a2s .  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 = "abc".getBytes();
    Cipher cipher = Cipher.getInstance("RSA/None/PKCS1Padding", "BC");
    SecureRandom random = new SecureRandom();
    KeyPairGenerator generator = KeyPairGenerator.getInstance("RSA", "BC");

    generator.initialize(256, random);/*w w  w.j  a v a  2 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 {
    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 .  ja  va  2 s.co  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 = "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  w  w  w  .  j a  v  a2  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 {
    Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
    byte[] input = "input123".getBytes();
    byte[] keyBytes = new byte[] { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c,
            0x0d, 0x0e, 0x0f };//from   w  w  w . j  a v a  2  s.  c o  m

    SecretKeySpec key = new SecretKeySpec(keyBytes, "AES");
    Cipher cipher = Cipher.getInstance("AES/ECB/NoPadding", "BC");

    byte[] cipherText = new byte[input.length];
    cipher.init(Cipher.ENCRYPT_MODE, key);

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

    ctLength += cipher.doFinal(cipherText, ctLength);

    System.out.println("cipher text: " + new String(cipherText) + " bytes: " + ctLength);

    byte[] plainText = new byte[ctLength];

    cipher.init(Cipher.DECRYPT_MODE, key);

    int ptLength = cipher.update(cipherText, 0, ctLength, plainText, 0);

    ptLength += cipher.doFinal(plainText, ptLength);

    System.out.println("plain text : " + new String(plainText) + " bytes: " + ptLength);
}

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.ja v  a  2  s.c  om
    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");
}