sun.security.x509

Class X509Key

java.lang.Object

sun.security.x509.X509Key

All Implemented Interfaces:

java.io.Serializable, java.security.Key, java.security.PublicKey

public class X509Key
extends java.lang.Object
implements java.security.PublicKey

Holds an X.509 key, for example a public key found in an X.509 certificate. Includes a description of the algorithm to be used with the key; these keys normally are used as "SubjectPublicKeyInfo".

While this class can represent any kind of X.509 key, it may be desirable to provide subclasses which understand how to parse keying data. For example, RSA public keys have two members, one for the public modulus and one for the prime exponent. If such a class is provided, it is used when parsing X.509 keys. If one is not provided, the key still parses correctly.

Author:

David Brownell

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected AlgorithmId	algid
protected byte[]	encodedKey
protected byte[]	key Deprecated. Use the BitArray form which does not require keys to be byte aligned.

Constructor Summary

Constructors

Constructor and Description
X509Key() Default constructor.

Method Summary

Methods

Modifier and Type	Method and Description
void	decode(byte[] encodedKey)
void	decode(java.io.InputStream in) Initialize an X509Key object from an input stream.
byte[]	encode() Returns the DER-encoded form of the key as a byte array.
void	encode(DerOutputStream out) Encode SubjectPublicKeyInfo sequence on the DER output stream.
boolean	equals(java.lang.Object obj)
java.lang.String	getAlgorithm() Returns the algorithm to be used with this key.
AlgorithmId	getAlgorithmId() Returns the algorithm ID to be used with this key.
byte[]	getEncoded() Returns the DER-encoded form of the key as a byte array.
byte[]	getEncodedInternal()
java.lang.String	getFormat() Returns the format for this key: "X.509"
protected BitArray	getKey() Gets the key.
int	hashCode() Calculates a hash code value for the object.
static java.security.PublicKey	parse(DerValue in) Construct X.509 subject public key from a DER value.
protected void	parseKeyBits() Parse the key bits.
protected void	setKey(BitArray key) Sets the key in the BitArray form.
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

algid

protected AlgorithmId algid

key

@Deprecated
protected byte[] key

Deprecated. Use the BitArray form which does not require keys to be byte aligned.

The key bytes, without the algorithm information.

See Also:

setKey(BitArray), getKey()

encodedKey

protected byte[] encodedKey

Constructor Detail

X509Key

public X509Key()

Default constructor. The key constructed must have its key and algorithm initialized before it may be used, for example by using decode.

Method Detail

setKey

protected void setKey(BitArray key)

Sets the key in the BitArray form.

getKey

protected BitArray getKey()

Gets the key. The key may or may not be byte aligned.

Returns:

a BitArray containing the key.

parse

public static java.security.PublicKey parse(DerValue in)
                                     throws java.io.IOException

Construct X.509 subject public key from a DER value. If the runtime environment is configured with a specific class for this kind of key, a subclass is returned. Otherwise, a generic X509Key object is returned.

This mechanism gurantees that keys (and algorithms) may be freely manipulated and transferred, without risk of losing information. Also, when a key (or algorithm) needs some special handling, that specific need can be accomodated.

Parameters:

in - the DER-encoded SubjectPublicKeyInfo value

Throws:

java.io.IOException - on data format errors

parseKeyBits

protected void parseKeyBits()
                     throws java.io.IOException,
                            java.security.InvalidKeyException

Parse the key bits. This may be redefined by subclasses to take advantage of structure within the key. For example, RSA public keys encapsulate two unsigned integers (modulus and exponent) as DER values within the key bits; Diffie-Hellman and DSS/DSA keys encapsulate a single unsigned integer.

This function is called when creating X.509 SubjectPublicKeyInfo values using the X509Key member functions, such as parse and decode.

Throws:

java.io.IOException - on parsing errors.

java.security.InvalidKeyException - on invalid key encodings.

getAlgorithm

public java.lang.String getAlgorithm()

Returns the algorithm to be used with this key.

Specified by:

getAlgorithm in interface java.security.Key

getAlgorithmId

public AlgorithmId getAlgorithmId()

Returns the algorithm ID to be used with this key.

encode

public final void encode(DerOutputStream out)
                  throws java.io.IOException

Encode SubjectPublicKeyInfo sequence on the DER output stream.

Throws:

java.io.IOException - on encoding errors.

getEncoded

public byte[] getEncoded()

Returns the DER-encoded form of the key as a byte array.

Specified by:

getEncoded in interface java.security.Key

getEncodedInternal

public byte[] getEncodedInternal()
                          throws java.security.InvalidKeyException

Throws:

java.security.InvalidKeyException

getFormat

public java.lang.String getFormat()

Returns the format for this key: "X.509"

Specified by:

getFormat in interface java.security.Key

encode

public byte[] encode()
              throws java.security.InvalidKeyException

Returns the DER-encoded form of the key as a byte array.

Throws:

java.security.InvalidKeyException - on encoding errors.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

decode

public void decode(java.io.InputStream in)
            throws java.security.InvalidKeyException

Initialize an X509Key object from an input stream. The data on that input stream must be encoded using DER, obeying the X.509 SubjectPublicKeyInfo format. That is, the data is a sequence consisting of an algorithm ID and a bit string which holds the key. (That bit string is often used to encapsulate another DER encoded sequence.)

Subclasses should not normally redefine this method; they should instead provide a parseKeyBits method to parse any fields inside the key member.

The exception to this rule is that since private keys need not be encoded using the X.509 SubjectPublicKeyInfo format, private keys may override this method, encode, and of course getFormat.

Parameters:

in - an input stream with a DER-encoded X.509 SubjectPublicKeyInfo value

Throws:

java.security.InvalidKeyException - on parsing errors.

decode

public void decode(byte[] encodedKey)
            throws java.security.InvalidKeyException

Throws:

java.security.InvalidKeyException

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Calculates a hash code value for the object. Objects which are equal will also have the same hashcode.

Overrides:

hashCode in class java.lang.Object