net.i2p.crypto
Class CryptixAESEngine

java.lang.Object
  net.i2p.crypto.AESEngine
      net.i2p.crypto.CryptixAESEngine

public class CryptixAESEngine
extends AESEngine

Wrapper for AES cypher operation using Cryptix's Rijndael implementation. Implements CBC with a 16 byte IV. Problems: Only supports data of size mod 16 bytes - no inherent padding.

Author:

jrandom, thecrypto

Field Summary

Fields inherited from class net.i2p.crypto.AESEngine

_context, _log

Constructor Summary

CryptixAESEngine(I2PAppContext context)
see comments for main() below private static final boolean USE_SYSTEM_AES; static { boolean systemOK = false; try { systemOK = Cipher.getMaxAllowedKeyLength("AES") >= 256; } catch (GeneralSecurityException gse) { // a NoSuchAlgorithmException } catch (NoSuchMethodError nsme) { // JamVM, gij try { Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding"); SecretKeySpec key = new SecretKeySpec(new byte[32], "AES"); cipher.init(Cipher.ENCRYPT_MODE, key); systemOK = true; } catch (GeneralSecurityException gse) { } } USE_SYSTEM_AES = systemOK; //System.out.println("Using system AES? " + systemOK); }

Method Summary

void	decrypt(byte[] payload, int payloadIndex, byte[] out, int outIndex, SessionKey sessionKey, byte[] iv, int length) Decrypt the data with the session key
void	decrypt(byte[] payload, int payloadIndex, byte[] out, int outIndex, SessionKey sessionKey, byte[] iv, int ivOffset, int length) Decrypt the data with the session key.
void	decryptBlock(byte[] payload, int inIndex, SessionKey sessionKey, byte[] rv, int outIndex) decrypt exactly 16 bytes of data with the session key provided
void	encrypt(byte[] payload, int payloadIndex, byte[] out, int outIndex, SessionKey sessionKey, byte[] iv, int length) Encrypt the payload with the session key
void	encrypt(byte[] payload, int payloadIndex, byte[] out, int outIndex, SessionKey sessionKey, byte[] iv, int ivOffset, int length) Encrypt the payload with the session key.
void	encryptBlock(byte[] payload, int inIndex, SessionKey sessionKey, byte[] out, int outIndex) encrypt exactly 16 bytes using the session key

Methods inherited from class net.i2p.crypto.AESEngine

safeDecrypt, safeEncrypt

Methods inherited from class java.lang.Object

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

Constructor Detail

CryptixAESEngine

public CryptixAESEngine(I2PAppContext context)

see comments for main() below private static final boolean USE_SYSTEM_AES; static { boolean systemOK = false; try { systemOK = Cipher.getMaxAllowedKeyLength("AES") >= 256; } catch (GeneralSecurityException gse) { // a NoSuchAlgorithmException } catch (NoSuchMethodError nsme) { // JamVM, gij try { Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding"); SecretKeySpec key = new SecretKeySpec(new byte[32], "AES"); cipher.init(Cipher.ENCRYPT_MODE, key); systemOK = true; } catch (GeneralSecurityException gse) { } } USE_SYSTEM_AES = systemOK; //System.out.println("Using system AES? " + systemOK); }

Method Detail

encrypt

public void encrypt(byte[] payload,
                    int payloadIndex,
                    byte[] out,
                    int outIndex,
                    SessionKey sessionKey,
                    byte[] iv,
                    int length)

Description copied from class: AESEngine

Encrypt the payload with the session key

Overrides:

encrypt in class AESEngine

Parameters:

iv - must be 16 bytes

length - must be a multiple of 16

payload - data to be encrypted

payloadIndex - index into the payload to start encrypting

out - where to store the result

outIndex - where in out to start writing

sessionKey - private esession key to encrypt to

encrypt

public void encrypt(byte[] payload,
                    int payloadIndex,
                    byte[] out,
                    int outIndex,
                    SessionKey sessionKey,
                    byte[] iv,
                    int ivOffset,
                    int length)

Description copied from class: AESEngine

Encrypt the payload with the session key. This just copies payload to out, see extension for the real thing.

Overrides:

encrypt in class AESEngine

Parameters:

iv - must be 16 bytes

length - must be a multiple of 16

payload - data to be encrypted

payloadIndex - index into the payload to start encrypting

out - where to store the result

outIndex - where in out to start writing

sessionKey - private esession key to encrypt to

decrypt

public void decrypt(byte[] payload,
                    int payloadIndex,
                    byte[] out,
                    int outIndex,
                    SessionKey sessionKey,
                    byte[] iv,
                    int length)

Description copied from class: AESEngine

Decrypt the data with the session key

Overrides:

decrypt in class AESEngine

Parameters:

payload - data to be decrypted

payloadIndex - index into the payload to start decrypting

out - where to store the cleartext

outIndex - where in out to start writing

sessionKey - private session key to decrypt to

iv - IV for CBC

length - how much data to decrypt

decrypt

public void decrypt(byte[] payload,
                    int payloadIndex,
                    byte[] out,
                    int outIndex,
                    SessionKey sessionKey,
                    byte[] iv,
                    int ivOffset,
                    int length)

Description copied from class: AESEngine

Decrypt the data with the session key. This just copies payload to out, see extension for the real thing.

Overrides:

decrypt in class AESEngine

Parameters:

payload - data to be decrypted

payloadIndex - index into the payload to start decrypting

out - where to store the cleartext

outIndex - where in out to start writing

sessionKey - private session key to decrypt to

iv - IV for CBC

length - how much data to decrypt

encryptBlock

public final void encryptBlock(byte[] payload,
                               int inIndex,
                               SessionKey sessionKey,
                               byte[] out,
                               int outIndex)

encrypt exactly 16 bytes using the session key

Overrides:

encryptBlock in class AESEngine

Parameters:

payload - plaintext data, 16 bytes starting at inIndex

sessionKey - private session key

out - out parameter, 16 bytes starting at outIndex

decryptBlock

public final void decryptBlock(byte[] payload,
                               int inIndex,
                               SessionKey sessionKey,
                               byte[] rv,
                               int outIndex)

decrypt exactly 16 bytes of data with the session key provided

Overrides:

decryptBlock in class AESEngine

Parameters:

payload - encrypted data, 16 bytes starting at inIndex

sessionKey - private session key

rv - out parameter, 16 bytes starting at outIndex