Class RSAKEMCipherSpi

java.lang.Object

javax.crypto.CipherSpi

org.bouncycastle.jcajce.provider.asymmetric.rsa.RSAKEMCipherSpi

public class RSAKEMCipherSpi
extends CipherSpi

Cipher SPI implementing the ISO 18033-2 / RFC 9690 RSA-KEM key-transport scheme, registered under the JCE service name "RSA-KTS-KEM-KWS" and aliased against the id-kem-rsa object identifier (1.0.18033.2.2.4).

Driven by the CMS pipeline through

invalid reference

org.bouncycastle.cms.jcajce.JceKEMRecipientInfoGenerator

(wrap) and

invalid reference

org.bouncycastle.cms.jcajce.JceKEMEnvelopedRecipient

(unwrap) when the recipient holds an RSA key; the analogous peer for ML-KEM is MLKEMCipherSpi.

Cipher operates in WRAP_MODE / UNWRAP_MODE only and requires a KTSParameterSpec carrying the KDF (KDF2 / KDF3 / HKDF per RFC 9690 §4) and the AES-Wrap variant. Wrap output is the RSA-KEM ciphertext (modulus-byte length) concatenated with the AES-wrapped CEK; the CMS caller splits them based on the modulus length.

Constructor Summary

Constructors

Constructor	Description
RSAKEMCipherSpi()

Method Summary

Modifier and Type	Method	Description
protected byte[]	engineDoFinal(byte[] bytes, int i, int i1)
protected int	engineDoFinal(byte[] bytes, int i, int i1, byte[] bytes1, int i2)
protected int	engineGetBlockSize()
protected byte[]	engineGetIV()
protected int	engineGetKeySize(Key key)
protected int	engineGetOutputSize(int inputLen)
protected AlgorithmParameters	engineGetParameters()
protected void	engineInit(int opmode, Key key, AlgorithmParameters algorithmParameters, SecureRandom random)
protected void	engineInit(int opmode, Key key, SecureRandom random)
protected void	engineInit(int opmode, Key key, AlgorithmParameterSpec paramSpec, SecureRandom random)
protected void	engineSetMode(String mode)
protected void	engineSetPadding(String padding)
protected Key	engineUnwrap(byte[] wrappedKey, String wrappedKeyAlgorithm, int wrappedKeyType)
protected byte[]	engineUpdate(byte[] bytes, int i, int i1)
protected int	engineUpdate(byte[] bytes, int i, int i1, byte[] bytes1, int i2)
protected byte[]	engineWrap(Key key)

Methods inherited from class CipherSpi

engineDoFinal, engineUpdate, engineUpdateAAD, engineUpdateAAD

Methods inherited from class Object

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

Constructor Details

RSAKEMCipherSpi

public RSAKEMCipherSpi()

Method Details

engineSetMode

protected void engineSetMode(String mode)
                      throws NoSuchAlgorithmException

Specified by:

engineSetMode in class CipherSpi

Throws:

NoSuchAlgorithmException

engineSetPadding

protected void engineSetPadding(String padding)
                         throws NoSuchPaddingException

Specified by:

engineSetPadding in class CipherSpi

Throws:

NoSuchPaddingException

engineGetKeySize

protected int engineGetKeySize(Key key)

Overrides:

engineGetKeySize in class CipherSpi

engineGetBlockSize

protected int engineGetBlockSize()

Specified by:

engineGetBlockSize in class CipherSpi

engineGetOutputSize

protected int engineGetOutputSize(int inputLen)

Specified by:

engineGetOutputSize in class CipherSpi

engineGetIV

protected byte[] engineGetIV()

Specified by:

engineGetIV in class CipherSpi

engineGetParameters

protected AlgorithmParameters engineGetParameters()

Specified by:

engineGetParameters in class CipherSpi

engineInit

protected void engineInit(int opmode,
 Key key,
 SecureRandom random)
                   throws InvalidKeyException

Specified by:

engineInit in class CipherSpi

Throws:

InvalidKeyException

engineInit

protected void engineInit(int opmode,
 Key key,
 AlgorithmParameterSpec paramSpec,
 SecureRandom random)
                   throws InvalidKeyException,
InvalidAlgorithmParameterException

Specified by:

engineInit in class CipherSpi

Throws:

InvalidKeyException

InvalidAlgorithmParameterException

engineInit

protected void engineInit(int opmode,
 Key key,
 AlgorithmParameters algorithmParameters,
 SecureRandom random)
                   throws InvalidKeyException,
InvalidAlgorithmParameterException

Specified by:

engineInit in class CipherSpi

Throws:

InvalidKeyException

InvalidAlgorithmParameterException

engineUpdate

protected byte[] engineUpdate(byte[] bytes,
 int i,
 int i1)

Specified by:

engineUpdate in class CipherSpi

engineUpdate

protected int engineUpdate(byte[] bytes,
 int i,
 int i1,
 byte[] bytes1,
 int i2)
                    throws ShortBufferException

Specified by:

engineUpdate in class CipherSpi

Throws:

ShortBufferException

engineDoFinal

protected byte[] engineDoFinal(byte[] bytes,
 int i,
 int i1)
                        throws IllegalBlockSizeException,
BadPaddingException

Specified by:

engineDoFinal in class CipherSpi

Throws:

IllegalBlockSizeException

BadPaddingException

engineDoFinal

protected int engineDoFinal(byte[] bytes,
 int i,
 int i1,
 byte[] bytes1,
 int i2)
                     throws ShortBufferException,
IllegalBlockSizeException,
BadPaddingException

Specified by:

engineDoFinal in class CipherSpi

Throws:

ShortBufferException

IllegalBlockSizeException

BadPaddingException

engineWrap

protected byte[] engineWrap(Key key)
                     throws IllegalBlockSizeException,
InvalidKeyException

Overrides:

engineWrap in class CipherSpi

Throws:

IllegalBlockSizeException

InvalidKeyException

engineUnwrap

protected Key engineUnwrap(byte[] wrappedKey,
 String wrappedKeyAlgorithm,
 int wrappedKeyType)
                    throws InvalidKeyException,
NoSuchAlgorithmException

Overrides:

engineUnwrap in class CipherSpi

Throws:

InvalidKeyException

NoSuchAlgorithmException