Package pygar.zoneable

Class FieldCrypto

java.lang.Object
pygar.zoneable.FieldCrypto
Direct Known Subclasses:
FieldCryptoXmlTxt0
public abstract class FieldCrypto
extends java.lang.Object
Perform the innermost encryption step: the encryption of fields but not the semantic tags of the statements.

According to the original plan, this class is abstract because there may be alternative document encodings during development and perhaps even in deployment. Thus, we introduce this abstract class and work is done in a subclass: FieldCryptoXmlTxt0

See Also:
A potential alternative method would use document tree structures that are stored and transmitted in binary. In order to supply that alternative, it will be necessary write a new implementation in a subclass.

  • Field Summary

    Fields 
    Modifier and Type Field Description
    protected int cipherBlockSize  
    protected javax.crypto.Cipher cipherDecrypt  
    protected javax.crypto.Cipher cipherEncrypt  
    protected int cipherOutputSize  
    protected CryptoEngine crypto  
    protected java.security.Key key  
    protected EncryptedFieldTable table  

  • Constructor Summary

    Constructors 
    Constructor Description
    FieldCrypto​(CryptoEngine crypto, java.security.Key key, EncryptedFieldTable table)
    Create an object initializing it for encryption using the table definitions of the fields.

  • Method Summary

    Modifier and Type Method Description
    abstract boolean compareStreams​(java.io.InputStream inStream1, java.io.InputStream inStream2, java.lang.Double tolerance, EncryptedFieldTable table)
    Compare two streams containing XML documents containing fields described by the field table.
    abstract void decode​(java.io.InputStream in, java.io.OutputStream out)
    Decode the in stream applying the encryption algorithm to the fields as specified in the table and placing the results on the out stream.
    abstract java.lang.String decodeField​(EncryptedFieldTable.EFTYPE ftype, java.lang.String name, byte[] value)
    Decode a single encrypted field according to its type creating a clear text string for the value.
    abstract java.lang.String decodeField​(EncryptedFieldTable.Row row, java.lang.String value)
    Decode a single encrypted field according to its type creating a clear text string for the value.
    abstract void decryptPartiallyEncryptedStream​(java.io.InputStream inStream, java.io.OutputStream outStream, EncryptedFieldTable table)
    Decrypt the document on the inStream assuming it was partially encrypted with the current session encryption key.
    abstract void encode​(java.io.InputStream in, java.io.OutputStream out)
    Encode the in stream applying the encryption algorithm to the fields as specified in the table and placing results on the out stream.
    abstract java.lang.String encodeField​(EncryptedFieldTable.Row row, java.lang.String value)
    Encode a single field represented as a string creating an encrypted byte array using the field type specified.
    protected abstract java.lang.String encodeString​(java.lang.String s)
    Encode a string with a symmetric session key and return it as a string representation in hexadecimal.
    abstract void partiallyEncryptStream​(java.io.InputStream inStream, java.io.OutputStream outStream, EncryptedFieldTable table)
    Partially encrypt the input stream according to the specifications of the EncryptedFieldTable and using the current session key.
    abstract boolean verifyField​(EncryptedFieldTable.Row row, java.lang.Double tolerance, java.lang.String value1, java.lang.String value2)  

    Methods inherited from class java.lang.Object

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

  • Field Details

  • Constructor Details

    • FieldCrypto

      public FieldCrypto​(CryptoEngine crypto, java.security.Key key, EncryptedFieldTable table) throws java.security.NoSuchAlgorithmException, javax.crypto.NoSuchPaddingException, java.security.InvalidKeyException
      Create an object initializing it for encryption using the table definitions of the fields.
      Parameters:
      crypto - the CryptoEngine object for this configuration
      key - the symmetric encryption key
      table - the definitions of the fields
      Throws:
      java.security.NoSuchAlgorithmException
      javax.crypto.NoSuchPaddingException
      java.security.InvalidKeyException

  • Method Details

    • encode

      public abstract void encode​(java.io.InputStream in, java.io.OutputStream out) throws DocumentError
      Encode the in stream applying the encryption algorithm to the fields as specified in the table and placing results on the out stream.
      Parameters:
      in -
      out -
      Throws:
      DocumentError

    • decode

      public abstract void decode​(java.io.InputStream in, java.io.OutputStream out) throws CryptoException
      Decode the in stream applying the encryption algorithm to the fields as specified in the table and placing the results on the out stream.
      Parameters:
      in -
      out -
      Throws:
      CryptoException

    • encodeField

      public abstract java.lang.String encodeField​(EncryptedFieldTable.Row row, java.lang.String value) throws CryptoException
      Encode a single field represented as a string creating an encrypted byte array using the field type specified.
      Parameters:
      row - - from EncryptedFieldTable that describes the field
      value -
      Returns:
      encoded value as string of hexadecimal
      Throws:
      CryptoException

    • decodeField

      public abstract java.lang.String decodeField​(EncryptedFieldTable.EFTYPE ftype, java.lang.String name, byte[] value) throws CryptoException
      Decode a single encrypted field according to its type creating a clear text string for the value.
      Parameters:
      ftype - the type of the field
      name - the name of the field
      value -
      Returns:
      the decoded value as a string
      Throws:
      CryptoException

    • decodeField

      public abstract java.lang.String decodeField​(EncryptedFieldTable.Row row, java.lang.String value) throws CryptoException
      Decode a single encrypted field according to its type creating a clear text string for the value.
      Parameters:
      row - the description of the field
      value -
      Returns:
      the decoded value as a string
      Throws:
      CryptoException

    • partiallyEncryptStream

      public abstract void partiallyEncryptStream​(java.io.InputStream inStream, java.io.OutputStream outStream, EncryptedFieldTable table) throws javax.xml.stream.XMLStreamException, CryptoException
      Partially encrypt the input stream according to the specifications of the EncryptedFieldTable and using the current session key.
      Throws:
      javax.xml.stream.XMLStreamException
      CryptoException

    • decryptPartiallyEncryptedStream

      public abstract void decryptPartiallyEncryptedStream​(java.io.InputStream inStream, java.io.OutputStream outStream, EncryptedFieldTable table) throws javax.xml.stream.XMLStreamException, CryptoException
      Decrypt the document on the inStream assuming it was partially encrypted with the current session encryption key.
      Parameters:
      inStream -
      outStream -
      table -
      Throws:
      javax.xml.stream.XMLStreamException
      CryptoException

    • compareStreams

      public abstract boolean compareStreams​(java.io.InputStream inStream1, java.io.InputStream inStream2, java.lang.Double tolerance, EncryptedFieldTable table) throws javax.xml.stream.XMLStreamException, java.lang.Exception
      Compare two streams containing XML documents containing fields described by the field table. Check each field for equality. Allow a tolerance in the comparison of real value fields. Other fields are compared for exact identity. This test procedure is provided to check the results a round-trip encryption and decryption.
      Parameters:
      inStream1 - first xml document to compare
      inStream2 - second xml document
      tolerance - allowable difference between two real values as a fraction of value
      table - description of fields
      Returns:
      true if the documents and equal in every field within the tolerance
      Throws:
      javax.xml.stream.XMLStreamException
      java.lang.Exception

    • verifyField

      public abstract boolean verifyField​(EncryptedFieldTable.Row row, java.lang.Double tolerance, java.lang.String value1, java.lang.String value2) throws CryptoException
      Throws:
      CryptoException

    • encodeString

      protected abstract java.lang.String encodeString​(java.lang.String s) throws CryptoException
      Encode a string with a symmetric session key and return it as a string representation in hexadecimal.
      Parameters:
      s - - clear text string
      Returns:
      encoded string
      Throws:
      CryptoException