EncryptionXTEA

java.lang.Object
- org.mapdb.EncryptionXTEA

```
public final class EncryptionXTEA
extends java.lang.Object
```
An implementation of the EncryptionXTEA block cipher algorithm.
This implementation uses 32 rounds. The best attack reported as of 2009 is 36 rounds (Wikipedia).
It requires 32 byte long encryption key, so SHA256 password hash is used.

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`ALIGN` Blocks sizes are always multiples of this number.
`private static int`	`DELTA`
`private static int[]`	`K` The first 32 bits of the fractional parts of the cube roots of the first sixty-four prime numbers.
`private int`	`k0`
`private int`	`k1`
`private int`	`k10`
`private int`	`k11`
`private int`	`k12`
`private int`	`k13`
`private int`	`k14`
`private int`	`k15`
`private int`	`k16`
`private int`	`k17`
`private int`	`k18`
`private int`	`k19`
`private int`	`k2`
`private int`	`k20`
`private int`	`k21`
`private int`	`k22`
`private int`	`k23`
`private int`	`k24`
`private int`	`k25`
`private int`	`k26`
`private int`	`k27`
`private int`	`k28`
`private int`	`k29`
`private int`	`k3`
`private int`	`k30`
`private int`	`k31`
`private int`	`k4`
`private int`	`k5`
`private int`	`k6`
`private int`	`k7`
`private int`	`k8`
`private int`	`k9`

Constructor Summary

Constructors
Constructor and Description

EncryptionXTEA(byte[] password)

Constructors
Constructor and Description
`EncryptionXTEA(byte[] password)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`decrypt(byte[] bytes, int off, int len)`
`private void`	`decryptBlock(byte[] in, byte[] out, int off)`
`void`	`encrypt(byte[] bytes, int off, int len)`
`private void`	`encryptBlock(byte[] in, byte[] out, int off)`
`static byte[]`	`getHash(byte[] data)` Calculate the hash code for the given data.
`private static int`	`readInt(byte[] b, int i)`
`private static int`	`rot(int i, int count)`
`private static void`	`writeInt(byte[] b, int i, int value)`

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

Field Detail

ALIGN
```
public static final int ALIGN
```
Blocks sizes are always multiples of this number.

See Also:

Constant Field Values

DELTA
```
private static final int DELTA
```
See Also:

Constant Field Values

k0
```
private final int k0
```

k1
```
private final int k1
```

k2
```
private final int k2
```

k3
```
private final int k3
```

k4
```
private final int k4
```

k5
```
private final int k5
```

k6
```
private final int k6
```

k7
```
private final int k7
```

k8
```
private final int k8
```

k9
```
private final int k9
```

k10
```
private final int k10
```

k11
```
private final int k11
```

k12
```
private final int k12
```

k13
```
private final int k13
```

k14
```
private final int k14
```

k15
```
private final int k15
```

k16
```
private final int k16
```

k17
```
private final int k17
```

k18
```
private final int k18
```

k19
```
private final int k19
```

k20
```
private final int k20
```

k21
```
private final int k21
```

k22
```
private final int k22
```

k23
```
private final int k23
```

k24
```
private final int k24
```

k25
```
private final int k25
```

k26
```
private final int k26
```

k27
```
private final int k27
```

k28
```
private final int k28
```

k29
```
private final int k29
```

k30
```
private final int k30
```

k31
```
private final int k31
```

K
```
private static final int[] K
```
The first 32 bits of the fractional parts of the cube roots of the first sixty-four prime numbers. Used for SHA256 password hash

Constructor Detail

EncryptionXTEA

public EncryptionXTEA(byte[] password)

Method Detail

encrypt

public void encrypt(byte[] bytes,
                    int off,
                    int len)

decrypt

public void decrypt(byte[] bytes,
                    int off,
                    int len)

encryptBlock

private void encryptBlock(byte[] in,
                          byte[] out,
                          int off)

decryptBlock

private void decryptBlock(byte[] in,
                          byte[] out,
                          int off)

getHash
```
public static byte[] getHash(byte[] data)
```
Calculate the hash code for the given data.

Parameters:

data - the data to hash

Returns:

the hash code

rot

private static int rot(int i,
                       int count)

readInt

private static int readInt(byte[] b,
                           int i)

writeInt

private static void writeInt(byte[] b,
                             int i,
                             int value)

Class EncryptionXTEA

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

ALIGN

DELTA

k0

k1

k2

k3

k4

k5

k6

k7

k8

k9

k10

k11

k12

k13

k14

k15

k16

k17

k18

k19

k20

k21

k22

k23

k24

k25

k26

k27

k28

k29

k30

k31

K

Constructor Detail

EncryptionXTEA

Method Detail

encrypt

decrypt

encryptBlock

decryptBlock

getHash

rot

readInt

writeInt