Package javacard.security

Interface ECPrivateKey

All Superinterfaces:

ECKey, Key, PrivateKey

public interface ECPrivateKey
extends PrivateKey, ECKey

The ECPrivateKey interface is used to generate signatures on data using the ECDSA (Elliptic Curve Digital Signature Algorithm) and to generate shared secrets using the ECDH (Elliptic Curve Diffie-Hellman) algorithm. An implementation of ECPrivateKey interface must also implement the ECKey interface methods.

When all components of the key (S, A, B, G, R, Field) are set, the key is initialized and ready for use. In addition, the KeyAgreement algorithm type ALG_EC_SVDP_DHC requires that the cofactor, K, be initialized.

The notation used to describe parameters specific to the EC algorithm is based on the naming conventions established in [IEEE P1363].

See Also:

ECPublicKey, KeyBuilder, Signature, javacardx.crypto.KeyEncryption, KeyAgreement

Method Summary

Modifier and Type	Method	Description
short	getS(byte[] buffer, short offset)	Returns the value of the secret key in plaintext form.
void	setS(byte[] buffer, short offset, short length)	Sets the value of the secret key.

Methods inherited from interface javacard.security.ECKey

copyDomainParametersFrom, getA, getB, getField, getG, getK, getR, setA, setB, setFieldF2M, setFieldF2M, setFieldFP, setG, setK, setR

Methods inherited from interface javacard.security.Key

clearKey, getSize, getType, isInitialized

Method Detail

setS

void setS(byte[] buffer,
          short offset,
          short length)
   throws CryptoException

Sets the value of the secret key. The plain text data format is big-endian and right-aligned (the least significant bit is the least significant bit of last byte). Input parameter data is copied into the internal representation.

Note:

• If the key object implements the javacardx.crypto.KeyEncryption interface and the Cipher object specified via setKeyCipher() is not null, the key value is decrypted using the Cipher object.

Parameters:

buffer - the input buffer

offset - the offset into the input buffer at which the secret value is to begin

length - the byte length of the secret value

Throws:

CryptoException - with the following reason code:

• CryptoException.ILLEGAL_VALUE if the length parameter is 0 or invalid or the input key data is inconsistent with the key length or if input data decryption is required and fails.

getS

short getS(byte[] buffer,
           short offset)
    throws CryptoException

Returns the value of the secret key in plaintext form. The data format is big-endian and right-aligned (the least significant bit is the least significant bit of last byte).

Parameters:

buffer - the output buffer

offset - the offset into the input buffer at which the secret value is to begin

Returns:

the byte length of the secret value

Throws:

CryptoException - with the following reason code:

• CryptoException.UNINITIALIZED_KEY if the value of the secret key has not been successfully initialized since the time the initialized state of the key was set to false.

See Also:

Key