SignatureOutputStream (IAIK PKCS#11 Provider API Documentation)

java.lang.Object
- java.io.OutputStream
- - java.io.FilterOutputStream
  - - iaik.pkcs.pkcs11.provider.signatures.SignatureOutputStream

All Implemented Interfaces:

java.io.Closeable, java.io.Flushable, java.lang.AutoCloseable
```
public class SignatureOutputStream
extends java.io.FilterOutputStream
```
This class implements a streaming version of a signature engine. It passes through all date written to this stream to the underlying stream and signs or verifies this passed through data. It is similar to the java.security.DigestOutputStream.

Author:

Karl Scheibelhofer

See Also:

Signature, DigestOutputStream

Invariants:

(in <> null) and (signatureEngine_ <> null)

Field Summary

Fields
Modifier and Type	Field and Description
`protected int`	`bytesProcessed_` The number of bytes that have been processed by this stream.
`protected boolean`	`isClosed_` True, if this stream has been closed.
`protected boolean`	`on_` Indicates if passed through data is signed or just passed through.
`protected boolean`	`passThroughClose_` True, if we should pass through a call to close.
`protected java.security.Signature`	`signatureEngine_` The signature engine that is used for signature creation and verification.

Fields inherited from class java.io.FilterOutputStream
out

Constructor Summary

Constructors
Constructor and Description
`SignatureOutputStream(java.io.OutputStream data, java.security.Signature signatureEngine, boolean passThroughClose)` Creates a streaming signature engine that reads its data from the provided stream.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`int`	`clearBytesProcessed()` Set the number of bytes that have been read so far to zero.
`void`	`close()` Close this stream and also the underlying stream if this has been specified at stream construction.
`int`	`getBytesProcessed()` Return the number of bytes that have been signed so far.
`java.security.Signature`	`getSignature()` Get the signature engine used by this stream.
`boolean`	`isOn()` Check if the signing/verification functionality is on or off.
`boolean`	`isStreamClosed()` Check, if this stream has been closed; i.e.
`boolean`	`setOn(boolean on)` Switch the signing/verification functionality on or off.
`void`	`setSignature(java.security.Signature signatureEngine)` Set the signature engine used by this stream.
`java.lang.String`	`toString()` Get a string representation of this object for debugging.
`void`	`write(byte[] buffer)` Write some bytes from the given buffer to the underlying output stream and updates the signature engine, if the signing function is on.
`void`	`write(byte[] buffer, int offset, int length)` Write some bytes from the given buffer to the underlying output stream and updates the signature engine, if the signing function is on.
`void`	`write(int dataByte)` Writes a byte to the underlying input stream and updates the signature engine, if the signing function is on.

Methods inherited from class java.io.FilterOutputStream
flush

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - on_
```
protected boolean on_
```
    Indicates if passed through data is signed or just passed through.
  - signatureEngine_
```
protected java.security.Signature signatureEngine_
```
    The signature engine that is used for signature creation and verification.
  - isClosed_
```
protected boolean isClosed_
```
    True, if this stream has been closed.
  - bytesProcessed_
```
protected int bytesProcessed_
```
    The number of bytes that have been processed by this stream.
  - passThroughClose_
```
protected boolean passThroughClose_
```
    True, if we should pass through a call to close.
- Constructor Detail
  - SignatureOutputStream
```
public SignatureOutputStream(java.io.OutputStream data,
                             java.security.Signature signatureEngine,
                             boolean passThroughClose)
```
    Creates a streaming signature engine that reads its data from the provided stream. It uses the given signature engine.
    
    Parameters:
    
    data - The input stream proving the data.
    
    signatureEngine - The signature object used to create and verify signatures.
    
    passThroughClose - If true, a call to close will ba passed through.
    
    Preconditions:
    
    (data <> null) and (signatureEngine <> null)
- Method Detail
  - getSignature
```
public java.security.Signature getSignature()
```
    Get the signature engine used by this stream.
    
    Returns:
    
    The signature engien used by this stream.
    
    See Also:
    
    setSignature(java.security.Signature)
    
    Postconditions:
    
    (result <> null)
  - setSignature
```
public void setSignature(java.security.Signature signatureEngine)
```
    Set the signature engine used by this stream.
    
    Parameters:
    
    signatureEngine - The signature engine used by this stream.
    
    See Also:
    
    getSignature()
    
    Preconditions:
    
    (signatureEngine <> null)
  - write
```
public void write(int dataByte)
           throws java.io.IOException
```
    Writes a byte to the underlying input stream and updates the signature engine, if the signing function is on. After sending this byte to the signature engine, it returns it.
    
    Overrides:
    
    write in class java.io.FilterOutputStream
    
    Parameters:
    
    dataByte - The byte to be written.
    
    Throws:
    
    java.io.IOException - if writing to the underlying stream fails or if updating the signature fails.
    
    See Also:
    
    Signature.update(byte)
  - write
```
public void write(byte[] buffer,
                  int offset,
                  int length)
           throws java.io.IOException
```
    Write some bytes from the given buffer to the underlying output stream and updates the signature engine, if the signing function is on.
    
    Overrides:
    
    write in class java.io.FilterOutputStream
    
    Parameters:
    
    buffer - The buffer holding the data to write.
    
    offset - The offset where to start getting bytes from the buffer.
    
    length - The maximum number of bytes to read from the buffer and write to the stream.
    
    Throws:
    
    java.io.IOException - if reading from the underlying stream fails or if updating the signature fails.
    
    See Also:
    
    Signature.update(byte[], int, int)
    
    Preconditions:
    
    (buffer <> null) and ((offset + length) <= data.length)
  - write
```
public void write(byte[] buffer)
           throws java.io.IOException
```
    Write some bytes from the given buffer to the underlying output stream and updates the signature engine, if the signing function is on.
    
    Overrides:
    
    write in class java.io.FilterOutputStream
    
    Parameters:
    
    buffer - The buffer holding the data to write.
    
    Throws:
    
    java.io.IOException - if reading from the underlying stream fails or if updating the signature fails.
    
    See Also:
    
    Signature.update(byte[], int, int)
    
    Preconditions:
    
    (buffer <> null) and ((offset + length) <= data.length)
  - isOn
```
public boolean isOn()
```
    Check if the signing/verification functionality is on or off. If it is turned on, all data read from this stream is also passed to the signature engine. If it is off, the data is just passed through without passing it to the signature engine.
    
    Returns:
    
    boolean True, if the signing/verification functionality is on.
  - setOn
```
public boolean setOn(boolean on)
```
    Switch the signing/verification functionality on or off. If it is turned on, all data read from this stream is also passed to the signature engine. If it is off, the data is just passed through without passing it to the signature engine.
    
    Parameters:
    
    on - True, to switch the signing/verification functionality on, false, to switch it off.
    
    Returns:
    
    boolean The old value of the switch.
  - getBytesProcessed
```
public int getBytesProcessed()
```
    Return the number of bytes that have been signed so far.
    
    Returns:
    
    The number of bytes that have been signed so far.
    
    Postconditions:
    
    (result <> null)
  - clearBytesProcessed
```
public int clearBytesProcessed()
```
    Set the number of bytes that have been read so far to zero.
    
    Returns:
    
    The old number of bytes that have been read so far before setting it to zero.
    
    Postconditions:
    
    (result >= 0)
  - close
```
public void close()
           throws java.io.IOException
```
    Close this stream and also the underlying stream if this has been specified at stream construction.
    
    Specified by:
    
    close in interface java.io.Closeable
    
    Specified by:
    
    close in interface java.lang.AutoCloseable
    
    Overrides:
    
    close in class java.io.FilterOutputStream
    
    Throws:
    
    java.io.IOException - If closing the underlying stream fails.
    
    See Also:
    
    SignatureOutputStream(OutputStream, Signature, boolean), OutputStream.close()
    
    Postconditions:
    
    (isStreamClosed() == true)
  - isStreamClosed
```
public boolean isStreamClosed()
```
    Check, if this stream has been closed; i.e. if close() has been called.
    
    Returns:
    
    boolean True, if this stream has been closed.
    
    Postconditions:
    
    (result <> null)
  - toString
```
public java.lang.String toString()
```
    Get a string representation of this object for debugging.
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    
    A string representation of this object for debugging.
    
    Postconditions:
    
    (result <> null)

IAIK JavaSecurity Website https://jce.iaik.tugraz.at/

IAIK at Graz University of Technology, Austria, Europe
Copyright 2001-2023 IAIK, Graz University of Technology, Inffeldgasse 16a, 8010 Graz, Austria. All Rights Reserved. Version 1.9.4

Class SignatureOutputStream

Field Summary

Fields inherited from class java.io.FilterOutputStream

Constructor Summary

Method Summary

Methods inherited from class java.io.FilterOutputStream

Methods inherited from class java.lang.Object

Field Detail

on_

signatureEngine_

isClosed_

bytesProcessed_

passThroughClose_

Constructor Detail

SignatureOutputStream

Method Detail

getSignature

setSignature

write

write

write

isOn

setOn

getBytesProcessed

clearBytesProcessed

close

isStreamClosed

toString