Package org.syncany.crypto

Class CipherSpec

java.lang.Object

org.syncany.crypto.CipherSpec

Direct Known Subclasses:

AesGcmCipherSpec, HmacSha256CipherSpec, TwofishGcmCipherSpec

public abstract class CipherSpec
extends java.lang.Object

A cipher spec represents the definition of a cipher/encryption algorithm and the corresponding settings required to instantiate a new cipher object.

Cipher specs are identified by an identifier (id), which will (when the cipher spec is used by the MultiCipherOutputStream) be written to the output file format. When the file is read by MultiCipherInputStream, the identifier is looked up using the CipherSpecs class.

While it would be technically possible to define any kind of cipher using this class, this class restricts the allowed algorithms to a few ones that are considered secure.

Instantiating a cipher spec that does pass the sanity checks will result in a RuntimeException.

Field Summary

Fields

Modifier and Type	Field	Description
static java.util.regex.Pattern	ALLOWED_CIPHER_ALGORITHMS

Constructor Summary

Constructors

Constructor	Description
CipherSpec(int id, java.lang.String algorithm, int keySize, int ivSize, boolean needsUnlimitedStrength)

Method Summary

Modifier and Type	Method	Description
boolean	equals(java.lang.Object obj)
java.lang.String	getAlgorithm()
int	getId()
int	getIvSize()
int	getKeySize()
int	hashCode()
boolean	needsUnlimitedStrength()
abstract java.io.InputStream	newCipherInputStream(java.io.InputStream underlyingInputStream, byte[] secretKey, byte[] iv)
abstract java.io.OutputStream	newCipherOutputStream(java.io.OutputStream underlyingOutputStream, byte[] secretKey, byte[] iv)
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

ALLOWED_CIPHER_ALGORITHMS

public static final java.util.regex.Pattern ALLOWED_CIPHER_ALGORITHMS

Constructor Detail

CipherSpec

public CipherSpec(int id,
                  java.lang.String algorithm,
                  int keySize,
                  int ivSize,
                  boolean needsUnlimitedStrength)

Method Detail

getId

public int getId()

needsUnlimitedStrength

public boolean needsUnlimitedStrength()

getAlgorithm

public java.lang.String getAlgorithm()

getKeySize

public int getKeySize()

getIvSize

public int getIvSize()

newCipherOutputStream

public abstract java.io.OutputStream newCipherOutputStream(java.io.OutputStream underlyingOutputStream,
                                                           byte[] secretKey,
                                                           byte[] iv)
                                                    throws CipherException

Throws:

CipherException

newCipherInputStream

public abstract java.io.InputStream newCipherInputStream(java.io.InputStream underlyingInputStream,
                                                         byte[] secretKey,
                                                         byte[] iv)
                                                  throws CipherException

Throws:

CipherException

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object