Package com.ibm.di.security

Class RSACrypto

  • All Implemented Interfaces:
    Crypto
    public class RSACrypto
extends java.lang.Object
implements Crypto
    RSA encryption/decryption of data of any length. The pieces of data on which RSA can be normally operate are limited in size by the size of the RSA keys. To workaround that limitation this class implements a custom scheme, which uses RSA as a block cipher - the plaintext is divided into equally-sized blocks and each of them is RSA encrypted. This approach allows encryption/decyption over data of any length.
    Since:
    7.0

    • Constructor Summary

      Constructors 
      Constructor Description
      RSACrypto​(java.security.interfaces.RSAPublicKey publicKey, java.security.interfaces.RSAPrivateKey privateKey, java.security.Provider cryptoProvider)
      Initialize the object with the specified parameters.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      byte[] decrypt​(byte[] encryptedData)
      Decrypt data.
      byte[] encrypt​(byte[] data)
      Encrypt data.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

      • RSACrypto

        public RSACrypto​(java.security.interfaces.RSAPublicKey publicKey,
                 java.security.interfaces.RSAPrivateKey privateKey,
                 java.security.Provider cryptoProvider)
        Initialize the object with the specified parameters. Accepts an optional Java security provider, which will be used for encryption. If the provider is set to null, the implementation will rely on the provider list configured for the JRE.
        Parameters:
        publicKey - a RSA public key
        privateKey - a RSA private key
        cryptoProvider - a Java security provider

    • Method Detail

      • encrypt

        public byte[] encrypt​(byte[] data)
               throws java.lang.Exception
        Encrypt data. The public key is used for encryption (opposite of signing where the private key is used). This way the encrypted data can be decrypted only using the private key. A security feature of the PKCS#1 padding, which is predominantly used with RSA, is that encryption produces a different ciphertext each time, despite the input plaintext stays the same. Of course, all of these ciphertexts will decrypt to the same plaintext.
        Specified by:
        encrypt in interface Crypto
        Parameters:
        data - plaintext
        Returns:
        ciphertext
        Throws:
        java.lang.Exception - problem with encryption

      • decrypt

        public byte[] decrypt​(byte[] encryptedData)
               throws java.lang.Exception
        Decrypt data. Decryption is done using the private key.
        Specified by:
        decrypt in interface Crypto
        Parameters:
        encryptedData - ciphertext
        Returns:
        plaintext
        Throws:
        java.lang.Exception - problem with decryption