Prev Class | Next Class | Frames | No Frames |
Summary: Nested | Field | Method | Constr | Detail: Nested | Field | Method | Constr |
java.lang.Object
xjava.security.IJCE_Traceable
xjava.security.Cipher
engine
engineInitEncrypt
initEncrypt
implBuffering == true
to the constructor), or leave
it to the Cipher superclass (implBuffering
== false). When
the implementation handles buffering, data passed to update
is
passed directly on to engineUpdate
, and data passed to
crypt
is passed to engineUpdate
, followed
immediately by a call to engineCrypt
.
When the Cipher superclass handles buffering, up to one block is buffered,
in order to ensure that the length of data passed to engineUpdate
is always a multiple of the block size. In this case the engineCrypt
method is not used.
Cipher implementations are not required or expected to be threadsafe.
If methods of a single Cipher object are called simultaneously by more
than one thread, the result will be unpredictable.
Copyright © 1997
Systemics Ltd on behalf of the
Cryptix Development Team.
Field Summary | |
static int |
|
static int |
|
static int |
|
Fields inherited from class xjava.security.IJCE_Traceable | |
tracing |
Constructor Summary | |
| |
| |
|
Method Summary | |
int |
|
Object |
|
byte[] |
|
byte[] |
|
int |
|
byte[] |
|
byte[] |
|
int |
|
int |
|
protected int |
|
protected int |
|
protected int |
|
protected Object |
|
protected int |
|
protected abstract void |
|
protected abstract void |
|
protected int |
|
protected int |
|
protected void |
|
protected void |
|
protected abstract int |
|
String |
|
static String[] |
|
static String[] |
|
int |
|
int |
|
static Cipher |
|
static Cipher |
|
static Cipher |
|
String |
|
int |
|
String |
|
protected PaddingScheme |
|
Object |
|
int |
|
String |
|
int |
|
int |
|
int |
|
void |
|
void |
|
boolean |
|
int |
|
int |
|
void |
|
String |
|
byte[] |
|
byte[] |
|
int |
|
int |
|
Methods inherited from class xjava.security.IJCE_Traceable | |
disableTracing , enableTracing , traceMethod , traceResult , traceResult , traceVoidMethod |
public static final int DECRYPT
The state of the cipher when it is ready to decrypt, that is, the state it is in right after a call toinitDecrypt
.
- Field Value:
- 2
- See Also:
initDecrypt(Key)
public static final int ENCRYPT
The state of the cipher when it is ready to encrypt, that is, the state it is in right after a call toinitEncrypt
.
- Field Value:
- 1
- See Also:
initEncrypt(Key)
public static final int UNINITIALIZED
The state of the cipher object when it is uninitialized, that is, the state it is in right after it has been created.
- Field Value:
- 0
protected Cipher()
Deprecated.
The JCE docs say: "Constructor used for dynamic instantiation." I don't understand why this is needed. --DJH
protected Cipher(boolean implBuffering, String provider, String algorithm)
This constructor is identical to the previous one (with arguments boolean, boolean, String), except that it does not have the redundant implPadding parameter, and also allows the algorithm name to be specified. This constructor is not supported in JavaSoft's version of JCE.
- Parameters:
implBuffering
- if true, this argument indicates that data will always be passed from update/crypt to engineUpdate/engineCrypt without modification.provider
- the name of the provider of the underlying cryptographic engine.algorithm
- the name of this algorithm (optionally with mode and padding, separated by '/'), as it is configured in the properties file.
protected Cipher(boolean implBuffering, boolean implPadding, String provider)
Constructor for a Cipher. This constructor is only for use by subclasses, which should pass the correct arguments to convey their behaviour to the superclass. Applications cannot call this constructor directly. For byte-oriented stream ciphers (where the input block size is 1), buffering is not needed, and the implBuffering parameter has no effect. In this version of IJCE, implPadding must be false. If it is true, an IllegalArgumentException is thrown.
- Parameters:
implBuffering
- if true, this argument indicates that data will always be passed from update/crypt to engineUpdate/engineCrypt without modification.implPadding
- must be false.provider
- the name of the provider of the underlying cryptographic engine.
public final int blockSize()
Returns the length of a block for this cipher. If plaintext and ciphertext blocks are different lengths, this method throws an IllegalBlockSizeException.
- Returns:
- the length in bytes of a block.
public Object clone() throws CloneNotSupportedException
Returns a clone of this cipher. Note: In JavaSoft's version of JCE,Cipher.clone()
is protected. This is not very useful, since then an application (as opposed to the cipher implementation itself) is not able to call it.
public final byte[] crypt(byte[] in) throws IllegalBlockSizeException
Encrypts or decrypts the specified array of data, which will be automatically padded/unpadded as necessary. Whether the data is encrypted or decrypted depends on the cipher's initialization state. This method will automatically allocate an output buffer of the right size. If the final block is incomplete, the cipher must have a padding scheme other than "NONE", and it must be in the ENCRYPT state. If this is not the case, an IllegalBlockSizeException will be thrown. If the cipher is in the DECRYPT state and padding is being used, at least one full ciphertext block should be passed tocrypt
. This is necessary because the last block contains information needed to determine the length of the original plaintext.
- Parameters:
in
- the input data.
- Returns:
- the encryption or decryption result.
- Throws:
IllegalBlockSizeException
- if the final block cannot be padded or unpadded.
public final byte[] crypt(byte[] in, int offset, int length) throws IllegalBlockSizeException
Encrypts or decrypts the specified array of data, which will be automatically padded/unpadded as necessary. Whether the data is encrypted or decrypted depends on the cipher's initialization state. This method will automatically allocate an output buffer of the right size. If the final block is incomplete, the cipher must have a padding scheme other than "NONE", and it must be in the ENCRYPT state. If this is not the case, an IllegalBlockSizeException will be thrown. If the cipher is in the DECRYPT state and padding is being used, at least one full ciphertext block should be passed tocrypt
. This is necessary because the last block contains information needed to determine the length of the original plaintext.
- Parameters:
in
- the input data.offset
- the offset indicating where the subarray starts in the in array.length
- the length of the subarray.
- Returns:
- the encryption or decryption result.
- Throws:
IllegalBlockSizeException
- if the final block cannot be padded or unpadded.
public final int crypt(byte[] in, int inOffset, int inLen, byte[] out, int outOffset) throws IllegalBlockSizeException
Encrypts or decrypts the specified subarray of data, pads or unpads it as necessary, and places the result in the specified output buffer. Whether the data is encrypted or decrypted depends on the cipher's initialization state. If the final block is incomplete, the cipher must have a padding scheme other than "NONE", and it must be in the ENCRYPT state. If this is not the case, an IllegalBlockSizeException will be thrown. If the cipher is in the DECRYPT state and padding is being used, at least one full ciphertext block should be passed tocrypt
. This is necessary because the last block contains information needed to determine the length of the original plaintext.
- Parameters:
in
- the input data.inOffset
- the offset indicating where the subarray starts in the in array.inLen
- the length of the subarray.out
- the output buffer.outOffset
- the offset indicating where to start writing the result into the output buffer.
- Returns:
- the number of bytes written.
public final byte[] doFinal(byte[] in) throws IllegalBlockSizeException
Equivalent tocrypt(in)
. This method is not supported in JavaSoft's version of JCE. However, an equivalent method is declared in the JCE 1.2 preview documentation for javax.crypto.Cipher.
public final byte[] doFinal(byte[] in, int offset, int length) throws IllegalBlockSizeException
Equivalent tocrypt(in, offset, length)
. This method is not supported in JavaSoft's version of JCE. However, an equivalent method is declared in the JCE 1.2 preview documentation for javax.crypto.Cipher.
public final int doFinal(byte[] in, int inOffset, int inLen, byte[] out) throws IllegalBlockSizeException
Equivalent tocrypt(in, inOffset, inLen, out, 0)
. This method is not supported in JavaSoft's version of JCE. However, an equivalent method is declared in the JCE 1.2 preview documentation for javax.crypto.Cipher.
public final int doFinal(byte[] in, int inOffset, int inLen, byte[] out, int outOffset) throws IllegalBlockSizeException
Equivalent tocrypt(in, inOffset, inLen, out, outOffset)
. This method is not supported in JavaSoft's version of JCE. However, an equivalent method is declared in the JCE 1.2 preview documentation for javax.crypto.Cipher.
protected int engineBlockSize()
SPI: Returns the length of a block, in bytes. Ciphers for which plaintext and ciphertext blocks are the same size may override this method. Otherwise, both enginePlaintextBlockSize and engineCiphertextBlockSize should be overridden. The value may change wheninitEncrypt
orinitDecrypt
is called, but it should not change at other times.
- Returns:
- the length in bytes of a block for this cipher.
protected int engineCiphertextBlockSize()
SPI: Returns the length of a ciphertext block, in bytes. For byte-oriented stream ciphers, this method should return 1. The value may change wheninitEncrypt
orinitDecrypt
is called, but it should not change at other times. The default implementation returnsengineBlockSize()
.
- Returns:
- the length in bytes of a ciphertext block for this cipher.
protected int engineCrypt(byte[] out, int outOffset)
SPI: Process data buffered by this cipher implementation. This method is overriden by ciphers that handle their own buffering (i.e.implBuffering == true
). It should flush the internal buffer, and process any remaining data. By default, this method returns 0. Ciphers that passimplBuffering == false
to the superclass constructor need not override this method. SECURITY: if array arguments are passed to native code, the implementation must ensure that a buffer overflow or illegal memory access cannot occur, regardless of the arguments passed to this method. I.e. the native library should not be called if:out == null || outOffset <320 || (long)outOffset + (number of bytes to be written) > out.lengthNote that the(long)
cast is essential, because outOffset could be close toInteger.MAX_VALUE
. The native method being called should be private. This is important because untrusted code could subclass the cipher implementation, and call this method directly with any arguments.
- Parameters:
out
- the output buffer into which to write the result.
- Returns:
- the number of bytes written.
protected Object engineGetParameter(String param) throws NoSuchParameterException, InvalidParameterException
SPI: Gets the value of the specified algorithm parameter. This method supplies a general-purpose mechanism through which it is possible to get the various parameters of this object. A parameter may be any settable parameter for the algorithm, such as block size, a source of random bits for IV generation (if appropriate), or an indication of whether or not to perform a specific but optional computation. A uniform algorithm-specific naming scheme for each parameter is desirable but left unspecified at this time. The default implementation always throws a NoSuchParameterException. This method is not supported in JavaSoft's version of JCE.
- Parameters:
param
- the string name of the parameter.
- Returns:
- the object that represents the parameter value.
- Throws:
NoSuchParameterException
- if there is no parameter with name param for this cipher implementation.
protected int engineInBufferSize(int outLen, boolean isFinal)
SPI: Returns the minimum number of bytes of input, that will cause an output of outLen bytes from a call toengineUpdate
(when isFinal is false), or successive calls to bothengineUpdate
andengineCrypt
(when isFinal is true). IfimplBuffering
is false, this method need not take into account padding or buffered data when calculating the result. In this caseoutLen
will be a multiple of the output block size (this may only be true for IJCE, not for other implementations of JCE). The default implementation assumes that the output will have the same number of blocks as the input (i.e. the result isoutLen / getOutputBlockSize() * getInputBlockSize()
). You will need to override this method if the cipher handles its own buffering.
- Parameters:
outLen
- the number of bytes of outputisFinal
- whether the input includes the last block
- Returns:
- the length in bytes of the output block
protected abstract void engineInitDecrypt(Key key) throws KeyException
SPI: Initializes this cipher for decryption, using the specified key. After a call to this method, the cipher's state is set to DECRYPT.
- Parameters:
key
- the key to use for decryption.
protected abstract void engineInitEncrypt(Key key) throws KeyException
SPI: Initializes this cipher for encryption, using the specified key. After a call to this method, the cipher's state is set to ENCRYPT.
- Parameters:
key
- the key to use for encryption.
protected int engineOutBufferSize(int inLen, boolean isFinal)
SPI: Returns the length of output buffer required for a given length of input, in bytes.isFinal
is true when this is the final block of input. IfimplBuffering
is false, theinLen
parameter already takes into account the length of any required padding, and buffered data. In this caseinLen
will be a multiple of the input block size (this may only be true for IJCE, not for other implementations of JCE). The default implementation assumes that the output will have the same number of blocks as the input (i.e. the result isinLen / getInputBlockSize() * getOutputBlockSize()
). You will need to override this method if the cipher handles its own buffering.
- Parameters:
inLen
- the number of bytes of inputisFinal
- whether the last block is to be padded
- Returns:
- the length in bytes of the output block
protected int enginePlaintextBlockSize()
SPI: Returns the length of a plaintext block, in bytes. For byte-oriented stream ciphers, this method should return 1. The value may change wheninitEncrypt
orinitDecrypt
is called, but it should not change at other times. The default implementation returnsengineBlockSize()
.
- Returns:
- the length in bytes of a plaintext block for this cipher.
protected void engineSetPaddingScheme(PaddingScheme padding)
SPI: Sets the object that will implement padding for this cipher. Cipher implementations may override this method in order to be notified when the padding scheme is set (in this case they should always callsuper.engineSetPaddingScheme(padding)
). Normally, overriding this method is not required.
protected void engineSetParameter(String param, Object value) throws NoSuchParameterException, InvalidParameterException, InvalidParameterTypeException
SPI: Sets the specified algorithm parameter to the specified value. This method supplies a general-purpose mechanism through which it is possible to set the various parameters of this object. A parameter may be any settable parameter for the algorithm, such as block size, a source of random bits for IV generation (if appropriate), or an indication of whether or not to perform a specific but optional computation. A uniform algorithm-specific naming scheme for each parameter is desirable but left unspecified at this time. The default implementation always throws a NoSuchParameterException. This method is not supported in JavaSoft's version of JCE.
- Parameters:
param
- the string name of the parameter.value
- the parameter value.
- Throws:
NoSuchParameterException
- if there is no parameter with name param for this cipher implementation.InvalidParameterTypeException
- if value is the wrong type for this parameter.
protected abstract int engineUpdate(byte[] in, int inOffset, int inLen, byte[] out, int outOffset)
SPI: This is the main engine method for updating data. WhenimplBuffering
is true, this method will be called with the same data that is passed toupdate
orcrypt
(i.e. there will be exactly one call toengineUpdate
for each call toupdate
orcrypt
). WhenimplBuffering
is false, the Cipher superclass will ensure that when it calls this method, inLen is a non-negative multiple ofgetInputBlockSize()
. in and out may be the same array, and the input and output regions may overlap. A cipher implementation should not use any part of in or out as working storage for intermediate steps of the algorithm. It should copy only the final result into the out array. SECURITY: if array arguments are passed to native code, the implementation must ensure that a buffer overflow or illegal memory access cannot occur, regardless of the arguments passed to this method. I.e. the native library should not be called if:in == null || out == null || inLen <320 || inLen % (block size) != 0 || inOffset <320 || (long)inOffset + inLen > in.length || outOffset <320 || (long)outOffset + (number of bytes to be written) > out.lengthNote that the(long)
casts are essential, because inOffset or outOffset could be close toInteger.MAX_VALUE
. The native method being called should be private. This is important because untrusted code could subclass the cipher implementation, and call this method directly with any arguments.
- Parameters:
in
- the input data.inOffset
- the offset into in specifying where the data starts.inLen
- the length of the subarray.out
- the output array.outOffset
- the offset indicating where to start writing into the out array.
- Returns:
- the number of bytes written.
public final String getAlgorithm()
Returns this algorithm's standard cipher name (not including mode and padding). See International JCE Standard Algorithm Names for a list of Cipher algorithm names.
- Returns:
- the standard cipher name (such as "DES").
public static String[] getAlgorithms()
Gets the standard names of all Ciphers implemented by any installed provider. Algorithm names are not duplicated if they are supported by more than one provider (but specialized cipher/mode implementations are treated as distinct, for example "DES/CBC" is different from "DES"). This method is not supported in JavaSoft's version of JCE. For compatibility you may wish to useIJCE.getAlgorithms("Cipher")
instead.
- Since:
- IJCE 1.0.1
public static String[] getAlgorithms(Provider provider)
Gets the standard names of all Ciphers implemented by a provider. This method is not supported in JavaSoft's version of JCE. For compatibility you may wish to useIJCE.getAlgorithms(provider, "Cipher")
instead.
- Since:
- IJCE 1.0.1
public final int getCiphertextBlockSize()
Returns the length of a ciphertext block, in bytes. For byte-oriented stream ciphers, this method returns 1. This method is not supported in JavaSoft's version of JCE.
- Returns:
- the length in bytes of a ciphertext block for this cipher.
public final int getInputBlockSize()
Returns the length of an input block, in bytes. When the cipher is in encryption mode, this is the length of a plaintext block. When in decryption mode, it is the length of a ciphertext block. This method is not supported in JavaSoft's version of JCE.
- Returns:
- the length in bytes of an input block for this cipher.
public static Cipher getInstance(String algorithm) throws NoSuchAlgorithmException
Generates a Cipher object that implements the given algorithm. If the default provider package contains a class implementing the algorithm, an instance of that class is returned. If it is not available in the default package, other packages are searched. Any of the following formats can be used for the algorithm name:See International JCE Standard Algorithm Names for a list of Cipher algorithm names.
- Parameters:
algorithm
- the algorithm name, as described above.
- Returns:
- the new Cipher object, in the UNINITIALIZED state.
public static Cipher getInstance(String algorithm, String provider) throws NoSuchAlgorithmException, NoSuchProviderException
Generates a Cipher object that implements the given cipher, from the given provider. The format of the cipher specification is as described forgetInstance(String algorithm)
. If the algorithm is implemented using more than one component (cipher, mode, and padding scheme), all of them must come from the given provider. More flexibility can be obtained by using thegetInstance(Cipher, Mode, PaddingScheme)
factory method. For example, to request "DES" from the SUN provider, "CBC" from the Cryptix provider, and "PKCS#5" from any provider, use:Cipher.getInstance( Cipher.getInstance("DES", "SUN"), Mode.getInstance("CBC", "Cryptix"), PaddingScheme.getInstance("PKCS#5") )See International JCE Standard Algorithm Names for a list of Cipher algorithm names.
- Parameters:
algorithm
- the cipher specification.
- Returns:
- the new Cipher object, in the UNINITIALIZED state.
public static Cipher getInstance(Cipher cipher, Mode mode, PaddingScheme padding)
Generates a new Cipher object by composing the given Cipher, Mode and PaddingScheme objects. mode may be null (indicating ECB), and padding may be null (indicating NONE). This method is not supported in JavaSoft's version of JCE.
public final String getMode()
Returns this algorithm's standard mode name. See International JCE Standard Algorithm Names for a list of Mode algorithm names.
- Returns:
- the algorithm's standard mode name (such as "CBC")
public final int getOutputBlockSize()
Returns the length of an output block, in bytes. When the cipher is in encryption mode, this is the length of a ciphertext block. When in decryption mode, it is the length of a plaintext block. This method is not supported in JavaSoft's version of JCE.
- Returns:
- the length in bytes of an output block for this cipher.
public final String getPadding()
Returns this algorithm's standard padding scheme name. See International JCE Standard Algorithm Names for a list of PaddingScheme algorithm names.
- Returns:
- the algorithm's standard padding scheme name (such as "PKCS#7" or "NONE")
protected final PaddingScheme getPaddingScheme()
Returns the object implementing padding for this cipher, or null if there is no such object.
public Object getParameter(String param) throws NoSuchParameterException, InvalidParameterException
Gets the value of the specified algorithm parameter. This method supplies a general-purpose mechanism through which it is possible to get the various parameters of this object. A parameter may be any settable parameter for the algorithm, such as block size, a source of random bits for IV generation (if appropriate), or an indication of whether or not to perform a specific but optional computation. A uniform algorithm-specific naming scheme for each parameter is desirable but left unspecified at this time. This method is not supported in JavaSoft's version of JCE.
- Specified by:
- getParameter in interface Parameterized
- Parameters:
param
- the string name of the parameter.
- Returns:
- the object that represents the parameter value.
- Throws:
NoSuchParameterException
- if there is no parameter with name param for this cipher implementation.
public final int getPlaintextBlockSize()
Returns the length of a plaintext block, in bytes. For byte-oriented stream ciphers, this method returns 1. This method is not supported in JavaSoft's version of JCE.
- Returns:
- the length in bytes of a plaintext block for this cipher.
public final String getProvider()
Returns the name of the provider of this cipher.
- Returns:
- the provider name (such as "SUN" or "Cryptix")
public final int getState()
Returns the state of this Cipher object. Possible states are:
- Returns:
- the state of this cipher object.
- See Also:
UNINITIALIZED
,ENCRYPT
,DECRYPT
public final int inBufferSize(int outLen)
Returns the minimum number of bytes of input, that will cause an output of outLen bytes from a call toupdate
(i.e. not including padding). This call takes into account any incomplete block currently being buffered. This is used by CipherInputStream, for example, to calculate how much data must be read from its underlying stream before encryption or decryption. This method is not supported in JavaSoft's version of JCE.
- Parameters:
outLen
- the number of bytes of output required.
public final int inBufferSizeFinal(int outLen)
Returns the minimum number of bytes of input, that will cause an output of outLen bytes from a call tocrypt
(including padding for the final block of the stream, if applicable). This call takes into account any incomplete block currently being buffered. This method is not supported in JavaSoft's version of JCE.
- Parameters:
outLen
- the number of bytes of output required.
public final void initDecrypt(Key key) throws KeyException
Initializes this cipher for decryption, using the specified key. A successful call to this method puts the cipher in the DECRYPT state. This method may be called on a cipher in any state. Any state information (key, feedback buffer, ...) is lost and reset.
- Parameters:
key
- the key to use for decryption.
public final void initEncrypt(Key key) throws KeyException
Initializes this cipher for encryption, using the specified key. A successful call to this method puts the cipher in the ENCRYPT state. This method may be called on a cipher in any state. Any state information (key, feedback buffer, ...) is lost and reset.
- Parameters:
key
- the key to use for encryption.
public final boolean isPaddingBlockCipher()
Returns true if this cipher is a padding block cipher. A cipher is a padding block cipher iffgetPlaintextBlockSize() > 1 && getPaddingScheme() != null
. If getPlaintextBlockSize throws an exception, so will this method. This method is needed because CipherInputStream and CipherOutputStream use a different buffering algorithm for padding block ciphers. This method is not supported in JavaSoft's version of JCE.
public final int outBufferSize(int inLen)
Returns the size of the buffer necessary to hold the output resulting from a call toupdate
(i.e. not including padding). This call takes into account any incomplete block currently being buffered.
- Parameters:
inLen
- the number of bytes to process.
public final int outBufferSizeFinal(int inLen)
Returns the size of the buffer necessary to hold the output resulting from a call tocrypt
(including padding for the final block of the stream, if applicable). This call takes into account any incomplete block currently being buffered. This method is not supported in JavaSoft's version of JCE.
- Parameters:
inLen
- the number of bytes to process.
public void setParameter(String param, Object value) throws NoSuchParameterException, InvalidParameterException, InvalidParameterTypeException
Sets the specified algorithm parameter to the specified value. This method supplies a general-purpose mechanism through which it is possible to set the various parameters of this object. A parameter may be any settable parameter for the algorithm, such as block size, a source of random bits for IV generation (if appropriate), or an indication of whether or not to perform a specific but optional computation. A uniform algorithm-specific naming scheme for each parameter is desirable but left unspecified at this time. This method is not supported in JavaSoft's version of JCE.
- Specified by:
- setParameter in interface Parameterized
- Parameters:
param
- the string identifier of the parameter.value
- the parameter value.
- Throws:
NoSuchParameterException
- if there is no parameter with name param for this cipher implementation.InvalidParameterTypeException
- if value is the wrong type for this parameter.
public String toString()
public final byte[] update(byte[] in)
Encrypts or decrypts the specified array of data, which is not the final data in this stream. For block ciphers, if the last block so far is incomplete, it will be buffered and processed in subsequent calls toupdate
orcrypt
. Whether the data is encrypted or decrypted depends on the cipher's initialization state. This method will automatically allocate an output buffer of the right size. This method is not supported in JavaSoft's version of JCE. However, an equivalent method is declared in the JCE 1.2 preview documentation for javax.crypto.Cipher.
- Parameters:
in
- the input data.
- Returns:
- the encryption or decryption result.
public final byte[] update(byte[] in, int offset, int length)
Encrypts or decrypts the specified subarray of data, which is not the final data in this stream. For block ciphers, if the last block so far is incomplete, it will be buffered and processed in subsequent calls toupdate
orcrypt
. Whether the data is encrypted or decrypted depends on the cipher's initialization state. This method will automatically allocate an output buffer of the right size. This method is not supported in JavaSoft's version of JCE. However, an equivalent method is declared in the JCE 1.2 preview documentation for javax.crypto.Cipher.
- Parameters:
in
- the input data.offset
- the offset indicating where the subarray starts in the in array.length
- the length of the subarray.
- Returns:
- the encryption or decryption result.
public final int update(byte[] in, int inOffset, int inLen, byte[] out)
Encrypts or decrypts the specified subarray of data, which is not the final data in this stream, and places the result in the specified output buffer (starting at offset 0). For block ciphers, if the last block so far is incomplete, it will be buffered and processed in subsequent calls toupdate
orcrypt
. Whether the data is encrypted or decrypted depends on the cipher's initialization state.out.length
must be at leastoutBufferSize(inLen)
, otherwise an ArrayIndexOutOfBoundsException will be thrown (in this case it is not specified how much, if any, of the output will have been written). This method is not supported in JavaSoft's version of JCE. However, an equivalent method is declared in the JCE 1.2 preview documentation for javax.crypto.Cipher.
- Parameters:
in
- the input data.inOffset
- the offset indicating where the subarray starts in the in array.inLen
- the length of the subarray.out
- the output buffer.
- Returns:
- the number of bytes written.
public final int update(byte[] in, int inOffset, int inLen, byte[] out, int outOffset)
Encrypts or decrypts the specified subarray of data, which is not the final data in this stream, and places the result in the specified output buffer. For block ciphers, if the last block so far is incomplete, it will be buffered and processed in subsequent calls toupdate
orcrypt
. Whether the data is encrypted or decrypted depends on the cipher's initialization state.out.length
must be at least(long) outOffset + outBufferSize(inLen)
, otherwise an ArrayIndexOutOfBoundsException will be thrown (in this case it is not specified how much, if any, of the output will have been written). This method is not supported in JavaSoft's version of JCE. However, an equivalent method is declared in the JCE 1.2 preview documentation for javax.crypto.Cipher.
- Parameters:
in
- the input data.inOffset
- the offset indicating where the subarray starts in the in array.inLen
- the length of the subarray.out
- the output buffer.outOffset
- the offset indicating where to start writing the result into the output buffer.
- Returns:
- the number of bytes written.