Cipher class.
* All the abstract methods in this class must be implemented by each
* cryptographic service provider who wishes to supply the implementation
* of a particular cipher algorithm.
*
* In order to create an instance of Cipher, which
* encapsulates an instance of this CipherSpi class, an
* application calls one of the
* {@link Cipher#getInstance(java.lang.String) getInstance}
* factory methods of the
* {@link Cipher Cipher} engine class and specifies the requested
* transformation.
* Optionally, the application may also specify the name of a provider.
*
*
A transformation is a string that describes the operation (or * set of operations) to be performed on the given input, to produce some * output. A transformation always includes the name of a cryptographic * algorithm (e.g., DES), and may be followed by a feedback mode and * padding scheme. * *
A transformation is of the form: * *
(in the latter case, * provider-specific default values for the mode and padding scheme are used). * For example, the following is a valid transformation: * *
* Cipher c = Cipher.getInstance("DES/CBC/PKCS5Padding");
*
*
* A provider may supply a separate class for each combination
* of algorithm/mode/padding, or may decide to provide more generic
* classes representing sub-transformations corresponding to
* algorithm or algorithm/mode or algorithm//padding
* (note the double slashes),
* in which case the requested mode and/or padding are set automatically by
* the getInstance methods of Cipher, which invoke
* the {@link #engineSetMode(java.lang.String) engineSetMode} and
* {@link #engineSetPadding(java.lang.String) engineSetPadding}
* methods of the provider's subclass of CipherSpi.
*
*
A Cipher property in a provider master class may have one of
* the following formats:
*
*
* // provider's subclass of "CipherSpi" implements "algName" with
* // pluggable mode and padding
* Cipher.algName
*
*
*
* // provider's subclass of "CipherSpi" implements "algName" in the
* // specified "mode", with pluggable padding
* Cipher.algName/mode
*
*
*
* // provider's subclass of "CipherSpi" implements "algName" with the
* // specified "padding", with pluggable mode
* Cipher.algName//padding
*
*
*
* // provider's subclass of "CipherSpi" implements "algName" with the
* // specified "mode" and "padding"
* Cipher.algName/mode/padding
*
*
* For example, a provider may supply a subclass of CipherSpi
* that implements DES/ECB/PKCS5Padding, one that implements
* DES/CBC/PKCS5Padding, one that implements
* DES/CFB/PKCS5Padding, and yet another one that implements
* DES/OFB/PKCS5Padding. That provider would have the following
* Cipher properties in its master class:
*
*
* Cipher.DES/ECB/PKCS5Padding
*
*
*
* Cipher.DES/CBC/PKCS5Padding
*
*
*
* Cipher.DES/CFB/PKCS5Padding
*
*
*
* Cipher.DES/OFB/PKCS5Padding
*
*
* Another provider may implement a class for each of the above modes
* (i.e., one class for ECB, one for CBC, one for CFB,
* and one for OFB), one class for PKCS5Padding,
* and a generic DES class that subclasses from CipherSpi.
* That provider would have the following
* Cipher properties in its master class:
*
*
* Cipher.DES
*
*
* The getInstance factory method of the Cipher
* engine class follows these rules in order to instantiate a provider's
* implementation of CipherSpi for a
* transformation of the form "algorithm":
*
*
CipherSpi
* for the specified "algorithm".
* If the answer is YES, instantiate this * class, for whose mode and padding scheme default values (as supplied by * the provider) are used. *
If the answer is NO, throw a NoSuchAlgorithmException
* exception.
*
The getInstance factory method of the Cipher
* engine class follows these rules in order to instantiate a provider's
* implementation of CipherSpi for a
* transformation of the form "algorithm/mode/padding":
*
*
CipherSpi
* for the specified "algorithm/mode/padding" transformation.
* If the answer is YES, instantiate it. *
If the answer is NO, go to the next step. *
CipherSpi
* for the sub-transformation "algorithm/mode".
* If the answer is YES, instantiate it, and call
* engineSetPadding(padding) on the new instance.
*
If the answer is NO, go to the next step. *
CipherSpi
* for the sub-transformation "algorithm//padding" (note the double
* slashes).
* If the answer is YES, instantiate it, and call
* engineSetMode(mode) on the new instance.
*
If the answer is NO, go to the next step. *
CipherSpi
* for the sub-transformation "algorithm".
* If the answer is YES, instantiate it, and call
* engineSetMode(mode) and
* engineSetPadding(padding) on the new instance.
*
If the answer is NO, throw a NoSuchAlgorithmException
* exception.
*
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, padding, and AEAD tagging.
*
*
The actual output length of the next update or
* doFinal call may be smaller than the length returned by
* this method.
*
* @param inputLen the input length (in bytes)
*
* @return the required output buffer size (in bytes)
*/
protected abstract int engineGetOutputSize(int inputLen);
/**
* Returns the initialization vector (IV) in a new buffer.
*
*
This is useful in the context of password-based encryption or * decryption, where the IV is derived from a user-provided passphrase. * * @return 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. */ protected abstract byte[] engineGetIV(); /** * Returns the parameters used with this cipher. * *
The returned parameters may be the same that were used to initialize * this cipher, or may contain a combination of default and random * parameter values used by the underlying cipher implementation if this * cipher requires algorithm parameters but was not initialized with any. * * @return the parameters used with this cipher, or null if this cipher * does not use any parameters. */ protected abstract AlgorithmParameters engineGetParameters(); /** * 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 any algorithm parameters that cannot be
* derived from the given key, 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
* InvalidKeyException if it is being
* initialized for decryption or key unwrapping.
* The generated parameters can be retrieved using
* {@link #engineGetParameters() engineGetParameters} or
* {@link #engineGetIV() 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 underlying feedback or padding scheme)
* requires any random bytes (e.g., for parameter generation), it will get
* them from random.
*
*
Note that when a Cipher object is initialized, it loses all
* previously-acquired state. In other words, initializing a Cipher is
* equivalent to creating a new instance of that Cipher and initializing
* it.
*
* @param opmode the operation mode of this cipher (this is one of
* the following:
* ENCRYPT_MODE, DECRYPT_MODE,
* WRAP_MODE or UNWRAP_MODE)
* @param key the encryption key
* @param random the source of randomness
*
* @exception InvalidKeyException if the given key is inappropriate for
* initializing this cipher, or requires
* algorithm parameters that cannot be
* determined from the given key.
* @throws UnsupportedOperationException if {@code opmode} is
* {@code WRAP_MODE} or {@code UNWRAP_MODE} is not implemented
* by the cipher.
*/
protected abstract void engineInit(int opmode, Key key,
SecureRandom random)
throws InvalidKeyException;
/**
* 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 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
* {@link #engineGetParameters() engineGetParameters} or
* {@link #engineGetIV() 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 underlying feedback or padding scheme)
* requires any random bytes (e.g., for parameter generation), it will get
* them from random.
*
*
Note that when a Cipher object is initialized, it loses all
* previously-acquired state. In other words, initializing a Cipher is
* equivalent to creating a new instance of that Cipher and initializing
* it.
*
* @param opmode the operation mode of this cipher (this is one of
* the following:
* ENCRYPT_MODE, DECRYPT_MODE,
* WRAP_MODE or UNWRAP_MODE)
* @param key the encryption key
* @param params the algorithm parameters
* @param random the source of randomness
*
* @exception InvalidKeyException if the given key is inappropriate for
* initializing this cipher
* @exception InvalidAlgorithmParameterException if the given algorithm
* parameters are inappropriate for this cipher,
* or if this cipher requires
* algorithm parameters and params is null.
* @throws UnsupportedOperationException if {@code opmode} is
* {@code WRAP_MODE} or {@code UNWRAP_MODE} is not implemented
* by the cipher.
*/
protected abstract void engineInit(int opmode, Key key,
AlgorithmParameterSpec params,
SecureRandom random)
throws InvalidKeyException, InvalidAlgorithmParameterException;
/**
* 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 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
* {@link #engineGetParameters() engineGetParameters} or
* {@link #engineGetIV() 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 underlying feedback or padding scheme)
* requires any random bytes (e.g., for parameter generation), it will get
* them from random.
*
*
Note that when a Cipher object is initialized, it loses all
* previously-acquired state. In other words, initializing a Cipher is
* equivalent to creating a new instance of that Cipher and initializing
* it.
*
* @param opmode the operation mode of this cipher (this is one of
* the following:
* ENCRYPT_MODE, DECRYPT_MODE,
* WRAP_MODE or UNWRAP_MODE)
* @param key the encryption key
* @param params the algorithm parameters
* @param random the source of randomness
*
* @exception InvalidKeyException if the given key is inappropriate for
* initializing this cipher
* @exception InvalidAlgorithmParameterException if the given algorithm
* parameters are inappropriate for this cipher,
* or if this cipher requires
* algorithm parameters and params is null.
* @throws UnsupportedOperationException if {@code opmode} is
* {@code WRAP_MODE} or {@code UNWRAP_MODE} is not implemented
* by the cipher.
*/
protected abstract void engineInit(int opmode, Key key,
AlgorithmParameters params,
SecureRandom random)
throws InvalidKeyException, InvalidAlgorithmParameterException;
/**
* 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 inclusive, are processed,
* and the result is stored in a new buffer.
*
* @param input the input buffer
* @param inputOffset the offset in input where the input
* starts
* @param inputLen the input length
*
* @return the new buffer with the result, or null if the underlying
* cipher is a block cipher and the input data is too short to result in a
* new block.
*/
protected abstract byte[] engineUpdate(byte[] input, int inputOffset,
int inputLen);
/**
* 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 inclusive, are processed,
* and the result is stored in the output buffer, starting at
* outputOffset inclusive.
*
*
If the output buffer is too small to hold the result,
* a ShortBufferException is thrown.
*
* @param input the input buffer
* @param inputOffset the offset in input where the input
* starts
* @param inputLen the input length
* @param output the buffer for the result
* @param outputOffset the offset in output where the result
* is stored
*
* @return the number of bytes stored in output
*
* @exception ShortBufferException if the given output buffer is too small
* to hold the result
*/
protected abstract int engineUpdate(byte[] input, int inputOffset,
int inputLen, byte[] output,
int outputOffset)
throws ShortBufferException;
/**
* Continues a multiple-part encryption or decryption operation
* (depending on how this cipher was initialized), processing another data
* part.
*
*
All input.remaining() bytes starting at
* input.position() are processed. The result is stored
* in the output buffer.
* Upon return, the input buffer's position will be equal
* to its limit; its limit will not have changed. The output buffer's
* position will have advanced by n, where n is the value returned
* by this method; the output buffer's limit will not have changed.
*
*
If output.remaining() bytes are insufficient to
* hold the result, a ShortBufferException is thrown.
*
*
Subclasses should consider overriding this method if they can
* process ByteBuffers more efficiently than byte arrays.
*
* @param input the input ByteBuffer
* @param output the output ByteByffer
*
* @return the number of bytes stored in output
*
* @exception ShortBufferException if there is insufficient space in the
* output buffer
*
* @throws NullPointerException if either parameter is null
* @since 1.5
*/
protected int engineUpdate(ByteBuffer input, ByteBuffer output)
throws ShortBufferException {
try {
return bufferCrypt(input, output, true);
} catch (IllegalBlockSizeException e) {
// never thrown for engineUpdate()
throw new ProviderException("Internal error in update()");
} catch (BadPaddingException e) {
// never thrown for engineUpdate()
throw new ProviderException("Internal error in update()");
}
}
/**
* 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 inclusive, and any input
* bytes that may have been buffered during a previous update
* operation, are processed, with padding (if requested) being applied.
* If an AEAD mode such as GCM/CCM is being used, the authentication
* tag is appended in the case of encryption, or verified in the
* case of decryption.
* The result is stored in a new buffer.
*
*
Upon finishing, this method resets this cipher object to the state
* it was in when previously initialized via a call to
* engineInit.
* That is, the object is reset and available to encrypt or decrypt
* (depending on the operation mode that was specified in the call to
* engineInit) more data.
*
*
Note: if any exception is thrown, this cipher object may need to
* be reset before it can be used again.
*
* @param input the input buffer
* @param inputOffset the offset in input where the input
* starts
* @param inputLen the input length
*
* @return the new buffer with the result
*
* @exception 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; or if this encryption algorithm is unable to
* process the input data provided.
* @exception 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
* @exception AEADBadTagException if this cipher is decrypting in an
* AEAD mode (such as GCM/CCM), and the received authentication tag
* does not match the calculated value
*/
protected abstract byte[] engineDoFinal(byte[] input, int inputOffset,
int inputLen)
throws IllegalBlockSizeException, BadPaddingException;
/**
* 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 inclusive, and any input
* bytes that may have been buffered during a previous update
* operation, are processed, with padding (if requested) being applied.
* If an AEAD mode such as GCM/CCM is being used, the authentication
* tag is appended in the case of encryption, or verified in the
* case of decryption.
* The result is stored in the output buffer, starting at
* outputOffset inclusive.
*
*
If the output buffer is too small to hold the result,
* a ShortBufferException is thrown.
*
*
Upon finishing, this method resets this cipher object to the state
* it was in when previously initialized via a call to
* engineInit.
* That is, the object is reset and available to encrypt or decrypt
* (depending on the operation mode that was specified in the call to
* engineInit) more data.
*
*
Note: if any exception is thrown, this cipher object may need to
* be reset before it can be used again.
*
* @param input the input buffer
* @param inputOffset the offset in input where the input
* starts
* @param inputLen the input length
* @param output the buffer for the result
* @param outputOffset the offset in output where the result
* is stored
*
* @return the number of bytes stored in output
*
* @exception 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; or if this encryption algorithm is unable to
* process the input data provided.
* @exception ShortBufferException if the given output buffer is too small
* to hold the result
* @exception 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
* @exception AEADBadTagException if this cipher is decrypting in an
* AEAD mode (such as GCM/CCM), and the received authentication tag
* does not match the calculated value
*/
protected abstract int engineDoFinal(byte[] input, int inputOffset,
int inputLen, byte[] output,
int outputOffset)
throws ShortBufferException, IllegalBlockSizeException,
BadPaddingException;
/**
* 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.
*
*
All input.remaining() bytes starting at
* input.position() are processed.
* If an AEAD mode such as GCM/CCM is being used, the authentication
* tag is appended in the case of encryption, or verified in the
* case of decryption.
* The result is stored in the output buffer.
* Upon return, the input buffer's position will be equal
* to its limit; its limit will not have changed. The output buffer's
* position will have advanced by n, where n is the value returned
* by this method; the output buffer's limit will not have changed.
*
*
If output.remaining() bytes are insufficient to
* hold the result, a ShortBufferException is thrown.
*
*
Upon finishing, this method resets this cipher object to the state
* it was in when previously initialized via a call to
* engineInit.
* That is, the object is reset and available to encrypt or decrypt
* (depending on the operation mode that was specified in the call to
* engineInit) more data.
*
*
Note: if any exception is thrown, this cipher object may need to * be reset before it can be used again. * *
Subclasses should consider overriding this method if they can
* process ByteBuffers more efficiently than byte arrays.
*
* @param input the input ByteBuffer
* @param output the output ByteByffer
*
* @return the number of bytes stored in output
*
* @exception 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; or if this encryption algorithm is unable to
* process the input data provided.
* @exception ShortBufferException if there is insufficient space in the
* output buffer
* @exception 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
* @exception AEADBadTagException if this cipher is decrypting in an
* AEAD mode (such as GCM/CCM), and the received authentication tag
* does not match the calculated value
*
* @throws NullPointerException if either parameter is null
* @since 1.5
*/
protected int engineDoFinal(ByteBuffer input, ByteBuffer output)
throws ShortBufferException, IllegalBlockSizeException,
BadPaddingException {
return bufferCrypt(input, output, false);
}
// copied from sun.security.jca.JCAUtil
// will be changed to reference that method once that code has been
// integrated and promoted
static int getTempArraySize(int totalSize) {
return Math.min(4096, totalSize);
}
/**
* Implementation for encryption using ByteBuffers. Used for both
* engineUpdate() and engineDoFinal().
*/
private int bufferCrypt(ByteBuffer input, ByteBuffer output,
boolean isUpdate) throws ShortBufferException,
IllegalBlockSizeException, BadPaddingException {
if ((input == null) || (output == null)) {
throw new NullPointerException
("Input and output buffers must not be null");
}
int inPos = input.position();
int inLimit = input.limit();
int inLen = inLimit - inPos;
if (isUpdate && (inLen == 0)) {
return 0;
}
int outLenNeeded = engineGetOutputSize(inLen);
if (output.remaining() < outLenNeeded) {
throw new ShortBufferException("Need at least " + outLenNeeded
+ " bytes of space in output buffer");
}
boolean a1 = input.hasArray();
boolean a2 = output.hasArray();
if (a1 && a2) {
byte[] inArray = input.array();
int inOfs = input.arrayOffset() + inPos;
byte[] outArray = output.array();
int outPos = output.position();
int outOfs = output.arrayOffset() + outPos;
int n;
if (isUpdate) {
n = engineUpdate(inArray, inOfs, inLen, outArray, outOfs);
} else {
n = engineDoFinal(inArray, inOfs, inLen, outArray, outOfs);
}
input.position(inLimit);
output.position(outPos + n);
return n;
} else if (!a1 && a2) {
int outPos = output.position();
byte[] outArray = output.array();
int outOfs = output.arrayOffset() + outPos;
byte[] inArray = new byte[getTempArraySize(inLen)];
int total = 0;
do {
int chunk = Math.min(inLen, inArray.length);
if (chunk > 0) {
input.get(inArray, 0, chunk);
}
int n;
if (isUpdate || (inLen != chunk)) {
n = engineUpdate(inArray, 0, chunk, outArray, outOfs);
} else {
n = engineDoFinal(inArray, 0, chunk, outArray, outOfs);
}
total += n;
outOfs += n;
inLen -= chunk;
} while (inLen > 0);
output.position(outPos + total);
return total;
} else { // output is not backed by an accessible byte[]
byte[] inArray;
int inOfs;
if (a1) {
inArray = input.array();
inOfs = input.arrayOffset() + inPos;
} else {
inArray = new byte[getTempArraySize(inLen)];
inOfs = 0;
}
byte[] outArray = new byte[getTempArraySize(outLenNeeded)];
int outSize = outArray.length;
int total = 0;
boolean resized = false;
do {
int chunk =
Math.min(inLen, (outSize == 0? inArray.length : outSize));
if (!a1 && !resized && chunk > 0) {
input.get(inArray, 0, chunk);
inOfs = 0;
}
try {
int n;
if (isUpdate || (inLen != chunk)) {
n = engineUpdate(inArray, inOfs, chunk, outArray, 0);
} else {
n = engineDoFinal(inArray, inOfs, chunk, outArray, 0);
}
resized = false;
inOfs += chunk;
inLen -= chunk;
if (n > 0) {
output.put(outArray, 0, n);
total += n;
}
} catch (ShortBufferException e) {
if (resized) {
// we just resized the output buffer, but it still
// did not work. Bug in the provider, abort
throw (ProviderException)new ProviderException
("Could not determine buffer size").initCause(e);
}
// output buffer is too small, realloc and try again
resized = true;
outSize = engineGetOutputSize(chunk);
outArray = new byte[outSize];
}
} while (inLen > 0);
if (a1) {
input.position(inLimit);
}
return total;
}
}
/**
* Wrap a key.
*
*
This concrete method has been added to this previously-defined * abstract class. (For backwards compatibility, it cannot be abstract.) * It may be overridden by a provider to wrap a key. * Such an override is expected to throw an IllegalBlockSizeException or * InvalidKeyException (under the specified circumstances), * if the given key cannot be wrapped. * If this method is not overridden, it always throws an * UnsupportedOperationException. * * @param key the key to be wrapped. * * @return the wrapped key. * * @exception 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. * * @exception 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). * * @throws UnsupportedOperationException if this method is not supported. */ protected byte[] engineWrap(Key key) throws IllegalBlockSizeException, InvalidKeyException { throw new UnsupportedOperationException(); } /** * Unwrap a previously wrapped key. * *
This concrete method has been added to this previously-defined
* abstract class. (For backwards compatibility, it cannot be abstract.)
* It may be overridden by a provider to unwrap a previously wrapped key.
* Such an override is expected to throw an InvalidKeyException if
* the given wrapped key cannot be unwrapped.
* If this method is not overridden, it always throws an
* UnsupportedOperationException.
*
* @param wrappedKey the key to be unwrapped.
*
* @param wrappedKeyAlgorithm the algorithm associated with the wrapped
* key.
*
* @param wrappedKeyType the type of the wrapped key. This is one of
* SECRET_KEY, PRIVATE_KEY, or
* PUBLIC_KEY.
*
* @return the unwrapped key.
*
* @exception NoSuchAlgorithmException if no installed providers
* can create keys of type wrappedKeyType for the
* wrappedKeyAlgorithm.
*
* @exception InvalidKeyException if wrappedKey does not
* represent a wrapped key of type wrappedKeyType for
* the wrappedKeyAlgorithm.
*
* @throws UnsupportedOperationException if this method is not supported.
*/
protected Key engineUnwrap(byte[] wrappedKey,
String wrappedKeyAlgorithm,
int wrappedKeyType)
throws InvalidKeyException, NoSuchAlgorithmException
{
throw new UnsupportedOperationException();
}
/**
* Returns the key size of the given key object in bits.
*
This concrete method has been added to this previously-defined
* abstract class. It throws an UnsupportedOperationException
* if it is not overridden by the provider.
*
* @param key the key object.
*
* @return the key size of the given key object.
*
* @exception InvalidKeyException if key is invalid.
*/
protected int engineGetKeySize(Key key)
throws InvalidKeyException
{
throw new UnsupportedOperationException();
}
/**
* Continues a multi-part update of the Additional Authentication
* Data (AAD), using a subset of the provided buffer.
*
* Calls to this method provide AAD to the cipher when operating in * modes such as AEAD (GCM/CCM). If this cipher is operating in * either GCM or CCM mode, all AAD must be supplied before beginning * operations on the ciphertext (via the {@code update} and {@code * doFinal} methods). * * @param src the buffer containing the AAD * @param offset the offset in {@code src} where the AAD input starts * @param len the number of AAD bytes * * @throws IllegalStateException if this cipher is in a wrong state * (e.g., has not been initialized), does not accept AAD, or if * operating in either GCM or CCM mode and one of the {@code update} * methods has already been called for the active * encryption/decryption operation * @throws UnsupportedOperationException if this method * has not been overridden by an implementation * * @since 1.7 */ protected void engineUpdateAAD(byte[] src, int offset, int len) { throw new UnsupportedOperationException( "The underlying Cipher implementation " + "does not support this method"); } /** * Continues a multi-part update of the Additional Authentication * Data (AAD). *
* Calls to this method provide AAD to the cipher when operating in * modes such as AEAD (GCM/CCM). If this cipher is operating in * either GCM or CCM mode, all AAD must be supplied before beginning * operations on the ciphertext (via the {@code update} and {@code * doFinal} methods). *
* All {@code src.remaining()} bytes starting at * {@code src.position()} are processed. * Upon return, the input buffer's position will be equal * to its limit; its limit will not have changed. * * @param src the buffer containing the AAD * * @throws IllegalStateException if this cipher is in a wrong state * (e.g., has not been initialized), does not accept AAD, or if * operating in either GCM or CCM mode and one of the {@code update} * methods has already been called for the active * encryption/decryption operation * @throws UnsupportedOperationException if this method * has not been overridden by an implementation * * @since 1.7 */ protected void engineUpdateAAD(ByteBuffer src) { throw new UnsupportedOperationException( "The underlying Cipher implementation " + "does not support this method"); } }