Implements abstract javax.crypto.CipherSpi.engineDoFinal.

Encrypts or decrypts data in a single-part operation, or finishes a multiple-part operation. The data is encrypted or decrypted, depending on how this cipher was initialized.

The first inputLen bytes in the input buffer, starting at inputOffset, and any input bytes that may have been buffered during a previous update operation, are processed, with padding (if requested) being applied. The result is stored in a new buffer.

The cipher is reset to its initial state (uninitialized) after this call.

Parameters

input:byte[]

the input buffer

inputOffset:int

the offset in input where the input starts

inputLen:int

the input length

Returns:byte[]

the new buffer with the result

Annotations

@Override

Exceptions

IllegalBlockSizeException:

if this cipher is a block cipher, no padding has been requested (only in encryption mode), and the total input length of the data processed by this cipher is not a multiple of block size

BadPaddingException:

if this cipher is in decryption mode, and (un)padding has been requested, but the decrypted data is not bounded by the appropriate padding bytes

Implements abstract javax.crypto.CipherSpi.engineDoFinal.

Encrypts or decrypts data in a single-part operation, or finishes a multiple-part operation. The data is encrypted or decrypted, depending on how this cipher was initialized.

The first inputLen bytes in the input buffer, starting at inputOffset, and any input bytes that may have been buffered during a previous update operation, are processed, with padding (if requested) being applied. The result is stored in the output buffer, starting at outputOffset.

The cipher is reset to its initial state (uninitialized) after this call.

Parameters

input:byte[]

the input buffer

inputOffset:int

the offset in input where the input starts

inputLen:int

the input length

output:byte[]

the buffer for the result

outputOffset:int

the offset in output where the result is stored

Returns:int

the number of bytes stored in output

Annotations

@Override

Exceptions

IllegalBlockSizeException:

if this cipher is a block cipher, no padding has been requested (only in encryption mode), and the total input length of the data processed by this cipher is not a multiple of block size

ShortBufferException:

if the given output buffer is too small to hold the result

BadPaddingException:

if this cipher is in decryption mode, and (un)padding has been requested, but the decrypted data is not bounded by the appropriate padding bytes

Implements abstract javax.crypto.CipherSpi.engineGetBlockSize.

Returns the block size (in bytes).

Returns:int

the block size (in bytes), or 0 if the underlying algorithm is not a block cipher

Annotations

@Override

Implements abstract javax.crypto.CipherSpi.engineGetIV.

Returns the initialization vector (IV) in a new buffer.

This is useful in the case where a random IV has been created (see init), or in the context of password-based encryption or decryption, where the IV is derived from a user-provided password.

Returns:byte[]

the initialization vector in a new buffer, or null if the underlying algorithm does not use an IV, or if the IV has not yet been set.

Annotations

@Override

Overrides javax.crypto.CipherSpi.engineGetKeySize.

Returns the key size of the given key object.

Parameters

key:Key

the key object.

Returns:int

the key size of the given key object.

Annotations

@Override

Exceptions

InvalidKeyException:

if key is invalid.

Implements abstract javax.crypto.CipherSpi.engineGetOutputSize.

Returns the length in bytes that an output buffer would need to be in order to hold the result of the next update or doFinal operation, given the input length inputLen (in bytes).

This call takes into account any unprocessed (buffered) data from a previous update call, and padding.

The actual output length of the next update or doFinal call may be smaller than the length returned by this method.

Parameters

inputLen:int

the input length (in bytes)

Returns:int

the required output buffer size (in bytes)

Annotations

@Override

Implements abstract javax.crypto.CipherSpi.engineGetParameters.

Returns the parameters used with this cipher.

The returned parameters may be the same that were used to initialize this cipher, or may contain the default set of parameters or a set of randomly generated parameters used by the underlying cipher implementation (provided that the underlying cipher implementation uses a default set of parameters or creates new parameters if it needs parameters but was not initialized with any).

Returns:AlgorithmParameters

the parameters used with this cipher, or null if this cipher does not use any parameters.

Annotations

@Override

Implements abstract javax.crypto.CipherSpi.engineInit.

Initializes this cipher with a key and a source of randomness.

The cipher is initialized for one of the following four operations: encryption, decryption, key wrapping or key unwrapping, depending on the value of opmode.

If this cipher requires an initialization vector (IV), it will get it from random. This behaviour should only be used in encryption or key wrapping mode, however. When initializing a cipher that requires an IV for decryption or key unwrapping, the IV (same IV that was used for encryption or key wrapping) must be provided explicitly as a parameter, in order to get the correct result.

This method also cleans existing buffer and other related state information.

Parameters

opmode:int

the operation mode of this cipher (this is one of the following: ENCRYPT_MODE, DECRYPT_MODE, WRAP_MODE or UNWRAP_MODE)

key:Key

the secret key

random:SecureRandom

the source of randomness

Annotations

@Override

Exceptions

InvalidKeyException:

if the given key is inappropriate for initializing this cipher

Implements abstract javax.crypto.CipherSpi.engineInit.

Initializes this cipher with a key, a set of algorithm parameters, and a source of randomness.

The cipher is initialized for one of the following four operations: encryption, decryption, key wrapping or key unwrapping, depending on the value of opmode.

If this cipher (including its underlying feedback or padding scheme) requires any random bytes, it will get them from random.

Parameters

opmode:int

the operation mode of this cipher (this is one of the following: ENCRYPT_MODE, DECRYPT_MODE, WRAP_MODE or UNWRAP_MODE)

key:Key

the encryption key

params:AlgorithmParameterSpec

the algorithm parameters

random:SecureRandom

the source of randomness

Annotations

@Override

Exceptions

InvalidKeyException:

if the given key is inappropriate for initializing this cipher

InvalidAlgorithmParameterException:

if the given algorithm parameters are inappropriate for this cipher

Implements abstract javax.crypto.CipherSpi.engineInit.

Doc from javax.crypto.CipherSpi.engineInit.

Initializes this CipherSpi object with a key, a set of algorithm parameters, and a source of randomness.

The CipherSpi object is initialized for one of the following four operations: encryption, decryption, key wrapping or key unwrapping, depending on the value of opmode.

If this cipher requires any algorithm parameters and params is null, the underlying cipher implementation is supposed to generate the required parameters itself (using provider-specific default or random values) if it is being initialized for encryption or key wrapping, and raise an InvalidAlgorithmParameterException if it is being initialized for decryption or key unwrapping. The generated parameters can be retrieved using engineGetParameters or engineGetIV (if the parameter is an IV).

If this cipher requires algorithm parameters that cannot be derived from the input parameters, and there are no reasonable provider-specific default values, initialization will necessarily fail.

If this cipher (including its feedback or padding scheme) requires any random bytes (e.g., for parameter generation), it will get them from random.

Note that when a CipherSpi object is initialized, it loses all previously-acquired state. In other words, initializing a CipherSpi object is equivalent to creating a new instance of that CipherSpi object and initializing it.

Annotations

@Override

Exceptions

InvalidKeyException:

if the given key is inappropriate for initializing this cipher

InvalidAlgorithmParameterException:

if the given algorithm parameters are inappropriate for this cipher, or if this cipher requires algorithm parameters and params is null

Implements abstract javax.crypto.CipherSpi.engineSetMode.

Sets the mode of this cipher.

Parameters

mode:String

the cipher mode

Annotations

@Override

Exceptions

NoSuchAlgorithmException:

if the requested cipher mode does not exist

Implements abstract javax.crypto.CipherSpi.engineSetPadding.

Sets the padding mechanism of this cipher.

Parameters

paddingScheme:String

the padding mechanism

Annotations

@Override

Exceptions

NoSuchPaddingException:

if the requested padding mechanism does not exist

Overrides javax.crypto.CipherSpi.engineUnwrap.

Unwrap a previously wrapped key.

Parameters

wrappedKey:byte[]

the key to be unwrapped.

wrappedKeyAlgorithm:String

the algorithm the wrapped key is for.

wrappedKeyType:int

the type of the wrapped key. This is one of Cipher.SECRET_KEY, Cipher.PRIVATE_KEY, or Cipher.PUBLIC_KEY.

Returns:Key

the unwrapped key.

Annotations

@Override

Exceptions

InvalidKeyException:

if wrappedKey does not represent a wrapped key of type wrappedKeyType for the wrappedKeyAlgorithm.

NoSuchAlgorithmException:

if no installed providers can create keys of type wrappedKeyType for the wrappedKeyAlgorithm.

Implements abstract javax.crypto.CipherSpi.engineUpdate.

Continues a multiple-part encryption or decryption operation (depending on how this cipher was initialized), processing another data part.

The first inputLen bytes in the input buffer, starting at inputOffset, are processed, and the result is stored in a new buffer.

Parameters

input:byte[]

the input buffer

inputOffset:int

the offset in input where the input starts

inputLen:int

the input length

Returns:byte[]

the new buffer with the result

Annotations

@Override

Exceptions

IllegalStateException:

if this cipher is in a wrong state (e.g., has not been initialized)

Implements abstract javax.crypto.CipherSpi.engineUpdate.

Continues a multiple-part encryption or decryption operation (depending on how this cipher was initialized), processing another data part.

The first inputLen bytes in the input buffer, starting at inputOffset, are processed, and the result is stored in the output buffer, starting at outputOffset.

Parameters

input:byte[]

the input buffer

inputOffset:int

the offset in input where the input starts

inputLen:int

the input length

output:byte[]

the buffer for the result

outputOffset:int

the offset in output where the result is stored

Returns:int

the number of bytes stored in output

Annotations

@Override

Exceptions

ShortBufferException:

if the given output buffer is too small to hold the result

Overrides javax.crypto.CipherSpi.engineWrap.

Wrap a key.

Parameters

key:Key

the key to be wrapped.

Returns:byte[]

the wrapped key.

Annotations

@Override

Exceptions

IllegalBlockSizeException:

if this cipher is a block cipher, no padding has been requested, and the length of the encoding of the key to be wrapped is not a multiple of the block size.

InvalidKeyException:

if it is impossible or unsafe to wrap the key with this cipher (e.g., a hardware protected key is being passed to a software only cipher).