org.bouncycastle.tls.crypto.impl

Class TlsBlockCipher

java.lang.Object

org.bouncycastle.tls.crypto.impl.TlsBlockCipher

All Implemented Interfaces:

TlsCipher

public class TlsBlockCipher
extends java.lang.Object
implements TlsCipher

A generic TLS 1.0-1.2 block cipher. This can be used for AES or 3DES for example.

Field Summary

Fields

Modifier and Type	Field and Description
protected TlsCrypto	crypto
protected TlsCryptoParameters	cryptoParams
protected TlsBlockCipherImpl	decryptCipher
protected TlsBlockCipherImpl	encryptCipher
protected boolean	encryptThenMAC
protected byte[]	randomData
protected TlsSuiteMac	readMac
protected boolean	useExplicitIV
protected boolean	useExtraPadding
protected TlsSuiteMac	writeMac

Constructor Summary

Constructors

Constructor and Description
TlsBlockCipher(TlsCrypto crypto, TlsCryptoParameters cryptoParams, TlsBlockCipherImpl encryptCipher, TlsBlockCipherImpl decryptCipher, TlsHMAC clientMac, TlsHMAC serverMac, int cipherKeySize)

Method Summary

Methods

Modifier and Type	Method and Description
protected int	checkPaddingConstantTime(byte[] buf, int off, int len, int blockSize, int macSize)
protected int	chooseExtraPadBlocks(java.security.SecureRandom r, int max)
byte[]	decodeCiphertext(long seqNo, short type, byte[] ciphertext, int offset, int len) Validate and decrypt the passed in cipher text using the current cipher suite.
byte[]	encodePlaintext(long seqNo, short type, byte[] plaintext, int offset, int len) Encrypt and MAC the passed in plain text using the current cipher suite.
int	getPlaintextLimit(int ciphertextLimit) Return the maximum size for the plaintext given ciphertextlimit bytes of ciphertext.
protected int	lowestBitSet(int x)

Methods inherited from class java.lang.Object

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

Field Detail

crypto

protected final TlsCrypto crypto

cryptoParams

protected final TlsCryptoParameters cryptoParams

randomData

protected final byte[] randomData

encryptThenMAC

protected final boolean encryptThenMAC

useExplicitIV

protected final boolean useExplicitIV

useExtraPadding

protected final boolean useExtraPadding

decryptCipher

protected final TlsBlockCipherImpl decryptCipher

encryptCipher

protected final TlsBlockCipherImpl encryptCipher

readMac

protected final TlsSuiteMac readMac

writeMac

protected final TlsSuiteMac writeMac

Constructor Detail

TlsBlockCipher

public TlsBlockCipher(TlsCrypto crypto,
              TlsCryptoParameters cryptoParams,
              TlsBlockCipherImpl encryptCipher,
              TlsBlockCipherImpl decryptCipher,
              TlsHMAC clientMac,
              TlsHMAC serverMac,
              int cipherKeySize)
               throws java.io.IOException

Throws:

java.io.IOException

Method Detail

getPlaintextLimit

public int getPlaintextLimit(int ciphertextLimit)

Description copied from interface: TlsCipher

Return the maximum size for the plaintext given ciphertextlimit bytes of ciphertext.

Specified by:

getPlaintextLimit in interface TlsCipher

Parameters:

ciphertextLimit - the maximum number of bytes of ciphertext.

Returns:

the maximum size of the plaintext for ciphertextlimit bytes of input.

encodePlaintext

public byte[] encodePlaintext(long seqNo,
                     short type,
                     byte[] plaintext,
                     int offset,
                     int len)
                       throws java.io.IOException

Description copied from interface: TlsCipher

Encrypt and MAC the passed in plain text using the current cipher suite.

Specified by:

encodePlaintext in interface TlsCipher

Parameters:

seqNo - sequence number of the message represented by plaintext.

type - content type of the message represented by plaintext.

plaintext - array holding input plain text to the cipher.

offset - offset into input array the plain text starts at.

len - length of the plaintext in the array.

Returns:

the resulting cipher text.

Throws:

java.io.IOException

decodeCiphertext

public byte[] decodeCiphertext(long seqNo,
                      short type,
                      byte[] ciphertext,
                      int offset,
                      int len)
                        throws java.io.IOException

Description copied from interface: TlsCipher

Validate and decrypt the passed in cipher text using the current cipher suite.

Specified by:

decodeCiphertext in interface TlsCipher

Parameters:

seqNo - sequence number of the message represented by ciphertext.

type - content type of the message represented by ciphertext.

ciphertext - array holding input cipher text to the cipher.

offset - offset into input array the cipher text starts at.

len - length of the cipher text in the array.

Returns:

the resulting plaintext.

Throws:

java.io.IOException

checkPaddingConstantTime

protected int checkPaddingConstantTime(byte[] buf,
                           int off,
                           int len,
                           int blockSize,
                           int macSize)

chooseExtraPadBlocks

protected int chooseExtraPadBlocks(java.security.SecureRandom r,
                       int max)

lowestBitSet

protected int lowestBitSet(int x)