freenet.support.io

Class PaddedEphemerallyEncryptedBucket

java.lang.Object

freenet.support.io.PaddedEphemerallyEncryptedBucket

All Implemented Interfaces:

Bucket, java.io.Serializable

public class PaddedEphemerallyEncryptedBucket
extends java.lang.Object
implements Bucket, java.io.Serializable

A proxy Bucket which adds: - Encryption with the supplied cipher, and a random, ephemeral key. - Padding to the next PO2 size. CRYPTO WARNING: This uses PCFB with no IV. That means it is only safe if the key is unique!

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static int	MAGIC
static int	MIN_PADDED_SIZE

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	PaddedEphemerallyEncryptedBucket()
	PaddedEphemerallyEncryptedBucket(Bucket bucket, int minSize, RandomSource strongPRNG, java.util.Random weakPRNG) Create a padded encrypted proxy bucket.
protected	PaddedEphemerallyEncryptedBucket(java.io.DataInputStream dis, FilenameGenerator fg, PersistentFileTracker persistentFileTracker, MasterSecret masterKey)
	PaddedEphemerallyEncryptedBucket(PaddedEphemerallyEncryptedBucket orig, Bucket newBucket)

Method Summary

Modifier and Type	Method and Description
Bucket	createShadow() Create a shallow read-only copy of this bucket, using different objects but using the same external storage.
void	free() Free the bucket, if supported.
java.io.InputStream	getInputStream() Returns an InputStream that reads data from this Bucket.
java.io.InputStream	getInputStreamUnbuffered()
byte[]	getKey() Get the decryption key.
java.lang.String	getName() Returns a name for the bucket, may be used to identify them in certain in certain situations.
java.io.OutputStream	getOutputStream() Returns an OutputStream that is used to put data in this Bucket, from the beginning.
java.io.OutputStream	getOutputStreamUnbuffered() Get an OutputStream which is not buffered.
PCFBMode	getPCFB()
Bucket	getUnderlying()
boolean	isReadOnly() Is the bucket read-only?
void	onResume(ClientContext context) Called after restarting.
long	paddedLength()
static long	paddedLength(long dataLength, long minPaddedSize) Return the length of the data in the proxied bucket, after padding.
void	setReadOnly() Make the bucket read-only.
long	size() Returns the amount of data currently in this bucket in bytes.
void	storeTo(java.io.DataOutputStream dos) Write enough data to reconstruct the Bucket, or throw UnsupportedOperationException.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

MIN_PADDED_SIZE

public static final int MIN_PADDED_SIZE

See Also:

Constant Field Values

MAGIC

public static final int MAGIC

See Also:

Constant Field Values

Constructor Detail

PaddedEphemerallyEncryptedBucket

public PaddedEphemerallyEncryptedBucket(Bucket bucket,
                                        int minSize,
                                        RandomSource strongPRNG,
                                        java.util.Random weakPRNG)

Create a padded encrypted proxy bucket.

Parameters:

bucket - The bucket which we are proxying to. Must be empty.

minSize - The minimum padded size of the file (after it has been closed).

strongPRNG - a strong prng we will key from.

weakPRNG - a week prng we will padd from. Serialization: Note that it is not our responsibility to free the random number generators, but we WILL free the underlying bucket.

Throws:

UnsupportedCipherException

PaddedEphemerallyEncryptedBucket

public PaddedEphemerallyEncryptedBucket(PaddedEphemerallyEncryptedBucket orig,
                                        Bucket newBucket)

PaddedEphemerallyEncryptedBucket

protected PaddedEphemerallyEncryptedBucket()

PaddedEphemerallyEncryptedBucket

protected PaddedEphemerallyEncryptedBucket(java.io.DataInputStream dis,
                                           FilenameGenerator fg,
                                           PersistentFileTracker persistentFileTracker,
                                           MasterSecret masterKey)
                                    throws StorageFormatException,
                                           java.io.IOException,
                                           ResumeFailedException

Throws:

StorageFormatException

java.io.IOException

ResumeFailedException

Method Detail

getOutputStream

public java.io.OutputStream getOutputStream()
                                     throws java.io.IOException

Description copied from interface: Bucket

Returns an OutputStream that is used to put data in this Bucket, from the beginning. It is not possible to append data to a Bucket! This simplifies the code significantly for some classes. If you need to append, just pass the OutputStream around. Will be buffered if appropriate (e.g. byte array backed buckets don't need to be buffered).

Specified by:

getOutputStream in interface Bucket

Throws:

java.io.IOException

getOutputStreamUnbuffered

public java.io.OutputStream getOutputStreamUnbuffered()
                                               throws java.io.IOException

Description copied from interface: Bucket

Get an OutputStream which is not buffered. Should be called when we will buffer the stream at a higher level or when we will only be doing large writes (e.g. copying data from one Bucket to another). Does not make any more persistence guarantees than getOutputStream() does, this is just to save memory.

Specified by:

getOutputStreamUnbuffered in interface Bucket

Throws:

java.io.IOException

getInputStream

public java.io.InputStream getInputStream()
                                   throws java.io.IOException

Description copied from interface: Bucket

Returns an InputStream that reads data from this Bucket. If there is no data in this bucket, null is returned. You have to call Closer.close(inputStream) on the obtained stream to prevent resource leakage.

Specified by:

getInputStream in interface Bucket

Throws:

java.io.IOException

getInputStreamUnbuffered

public java.io.InputStream getInputStreamUnbuffered()
                                             throws java.io.IOException

Specified by:

getInputStreamUnbuffered in interface Bucket

Throws:

java.io.IOException

paddedLength

public long paddedLength()

paddedLength

public static long paddedLength(long dataLength,
                                long minPaddedSize)

Return the length of the data in the proxied bucket, after padding.

getPCFB

public PCFBMode getPCFB()

getName

public java.lang.String getName()

Description copied from interface: Bucket

Returns a name for the bucket, may be used to identify them in certain in certain situations.

Specified by:

getName in interface Bucket

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

size

public long size()

Description copied from interface: Bucket

Returns the amount of data currently in this bucket in bytes.

Specified by:

size in interface Bucket

isReadOnly

public boolean isReadOnly()

Description copied from interface: Bucket

Is the bucket read-only?

Specified by:

isReadOnly in interface Bucket

setReadOnly

public void setReadOnly()

Description copied from interface: Bucket

Make the bucket read-only. Irreversible.

Specified by:

setReadOnly in interface Bucket

getUnderlying

public Bucket getUnderlying()

Returns:

The underlying Bucket.

free

public void free()

Description copied from interface: Bucket

Free the bucket, if supported. Note that you must call free() even if you haven't used the Bucket (haven't called getOutputStream()) for some kinds of Bucket's, as they may have allocated space (e.g. created a temporary file).

Specified by:

free in interface Bucket

getKey

public byte[] getKey()

Get the decryption key.

createShadow

public Bucket createShadow()

Description copied from interface: Bucket

Create a shallow read-only copy of this bucket, using different objects but using the same external storage. If this is not possible, return null. Note that if the underlying bucket is deleted, the copy will become invalid and probably throw an IOException on read, or possibly return too-short data etc. In some use cases e.g. on fproxy, this is acceptable.

Specified by:

createShadow in interface Bucket

onResume

public void onResume(ClientContext context)
              throws ResumeFailedException

Description copied from interface: Bucket

Called after restarting. The Bucket should do any necessary housekeeping after resuming, e.g. registering itself with the appropriate persistent bucket tracker to avoid being garbage-collected. May be called twice, so the Bucket may need to track this internally.

Specified by:

onResume in interface Bucket

Parameters:

context - All the necessary runtime support will be on this object.

Throws:

ResumeFailedException

storeTo

public void storeTo(java.io.DataOutputStream dos)
             throws java.io.IOException

Description copied from interface: Bucket

Write enough data to reconstruct the Bucket, or throw UnsupportedOperationException. Used for recovering in emergencies, should be versioned if necessary.

Specified by:

storeTo in interface Bucket

Throws:

java.io.IOException