Package com.amazonaws.encryptionsdk

Class CryptoInputStream<K extends MasterKey<K>>

java.lang.Object

java.io.InputStream

com.amazonaws.encryptionsdk.CryptoInputStream<K>

Type Parameters:

K - The type of MasterKeys used to manipulate the data.

All Implemented Interfaces:

Closeable, AutoCloseable

public class CryptoInputStream<K extends MasterKey<K>>
extends InputStream

A CryptoInputStream is a subclass of java.io.InputStream. It performs cryptographic transformation of the bytes passing through it.

The CryptoInputStream wraps a provided InputStream object and performs cryptographic transformation of the bytes read from the wrapped InputStream. It uses the cryptography handler provided during construction to invoke methods that perform the cryptographic transformations.

In short, reading from the CryptoInputStream returns bytes that are the cryptographic transformations of the bytes read from the wrapped InputStream.

For example, if the cryptography handler provides methods for decryption, the CryptoInputStream will read ciphertext bytes from the wrapped InputStream, decrypt, and return them as plaintext bytes.

This class adheres strictly to the semantics, especially the failure semantics, of its ancestor class java.io.InputStream. This class overrides all the methods specified in its ancestor class.

To instantiate an instance of this class, please see AwsCrypto.

Method Summary

Modifier and Type	Method	Description
int	available()	Returns metadata associated with the performed cryptographic operation.
void	close()
CryptoResult<CryptoInputStream<K>,K>	getCryptoResult()	Returns the result of the cryptographic operations including associate metadata.
int	read()	int
read(byte[] b)	int	read(byte[] b, int off, int len)
void	setMaxInputLength(long size)	Sets an upper bound on the size of the input data.

Methods inherited from class java.io.InputStream

mark, markSupported, nullInputStream, readAllBytes, readNBytes, readNBytes, reset, skip, skipNBytes, transferTo

Methods inherited from class java.lang.Object

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

Method Details

read

public int read(byte[] b,
 int off,
 int len)
         throws IllegalArgumentException,
IOException,
BadCiphertextException

Overrides:

read in class InputStream

Throws:

BadCiphertextException - This is thrown only during decryption if b contains invalid or corrupt ciphertext.

IllegalArgumentException

IOException

read

public int read(byte[] b)
         throws IllegalArgumentException,
IOException,
BadCiphertextException

Overrides:

read in class InputStream

Throws:

BadCiphertextException - This is thrown only during decryption if b contains invalid or corrupt ciphertext.

IllegalArgumentException

IOException

read

public int read()
         throws IOException,
BadCiphertextException

Specified by:

read in class InputStream

Throws:

BadCiphertextException - if b contains invalid or corrupt ciphertext. This is thrown only during decryption.

IOException

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class InputStream

Throws:

IOException

available

public int available()
              throws IOException

Returns metadata associated with the performed cryptographic operation.

Overrides:

available in class InputStream

Throws:

IOException

setMaxInputLength

public void setMaxInputLength(long size)

Sets an upper bound on the size of the input data. This method should be called before reading any data from the stream. If this method is not called prior to reading any data, performance may be reduced (notably, it will not be possible to cache data keys when encrypting).

Among other things, this size is used to enforce limits configured on the CachingCryptoMaterialsManager.

If the input size set here is exceeded, an exception will be thrown, and the encyption or decryption will fail.

If this method is called multiple times, the smallest bound will be used.

Parameters:

size - Maximum input size.

getCryptoResult

public CryptoResult<CryptoInputStream<K>,K> getCryptoResult()
                                                     throws BadCiphertextException,
IOException

Returns the result of the cryptographic operations including associate metadata.

Throws:

IOException

BadCiphertextException