Class OutputStreamAesGcmEncryption

java.lang.Object

java.io.OutputStream

com.itextpdf.kernel.crypto.OutputStreamEncryption

com.itextpdf.kernel.crypto.OutputStreamAesGcmEncryption

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable

public class OutputStreamAesGcmEncryption
extends OutputStreamEncryption

An output stream accepts output bytes and sends them to underlying OutputStreamEncryption instance.

Field Summary

Fields

Modifier and Type	Field	Description
private final AESGCMCipher	cipher
private boolean	finished
private static final SecureRandom	rng

Fields inherited from class OutputStreamEncryption

out

Constructor Summary

Constructors

Constructor	Description
OutputStreamAesGcmEncryption(OutputStream out, byte[] key, byte[] noncePart)	Creates a new instance of OutputStreamAesGcmEncryption.

Method Summary

Modifier and Type	Method	Description
void	finish()	Finishes and dispose all resources used for writing in encrypted stream.
void	write(byte[] b, int off, int len)	Writes len bytes from the specified byte array starting at offset off to this output stream.

Methods inherited from class OutputStreamEncryption

close, flush, write, write

Methods inherited from class OutputStream

nullOutputStream

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

cipher

private final AESGCMCipher cipher

finished

private boolean finished

rng

private static final SecureRandom rng

Constructor Details

OutputStreamAesGcmEncryption

public OutputStreamAesGcmEncryption(OutputStream out,
 byte[] key,
 byte[] noncePart)

Creates a new instance of OutputStreamAesGcmEncryption.

Parameters:

out - the OutputStream instance to be used as the destination for the encrypted content

key - the byte array containing the key for encryption

noncePart - a 7 byte nonce

Method Details

write

public void write(byte[] b,
 int off,
 int len)
           throws IOException

Writes len bytes from the specified byte array starting at offset off to this output stream. The general contract for write(b, off, len) is that some bytes in the array b are written to the output stream in order; element b[off] is the first byte written and b[off+len-1] is the last byte written by this operation.

The write method of OutputStream calls the write method of one argument on each of the bytes to be written out. Subclasses are encouraged to override this method and provide a more efficient implementation.

If off is negative, or len is negative, or off+len is greater than the length of the array b, then an IndexOutOfBoundsException is thrown.

Specified by:

write in class OutputStreamEncryption

Parameters:

b - the data

off - the start offset in the data

len - the number of bytes to write

Throws:

IOException - if an I/O error occurs. In particular, an IOException is thrown if the output stream is closed

finish

public void finish()

Finishes and dispose all resources used for writing in encrypted stream. Input data that may have been buffered during a previous update operation is processed, with padding (if requested) being applied and authentication tag is appended.

Specified by:

finish in class OutputStreamEncryption