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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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* 2 along with this work; if not, write to the Free Software Foundation,
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*
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package sun.security.x509;
import java.io.*;
import java.util.Arrays;
import java.util.Properties;
import java.security.Key;
import java.security.PublicKey;
import java.security.KeyFactory;
import java.security.KeyRep;
import java.security.Security;
import java.security.Provider;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.X509EncodedKeySpec;
import sun.misc.HexDumpEncoder;
import sun.security.util.*;
/**
* 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".
*
* <P>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
*/
public class X509Key implements PublicKey {
/** use serialVersionUID from JDK 1.1. for interoperability */
private static final long serialVersionUID = -5359250853002055002L;
/* The algorithm information (name, parameters, etc). */
protected AlgorithmId algid;
/**
* The key bytes, without the algorithm information.
* @deprecated Use the BitArray form which does not require keys to
* be byte aligned.
* @see sun.security.x509.X509Key#setKey(BitArray)
* @see sun.security.x509.X509Key#getKey()
*/
@Deprecated
protected byte[] key = null;
/*
* The number of bits unused in the last byte of the key.
* Added to keep the byte[] key form consistent with the BitArray
* form. Can de deleted when byte[] key is deleted.
*/
private int unusedBits = 0;
/* BitArray form of key */
private BitArray bitStringKey = null;
/* The encoding for the key. */
protected byte[] encodedKey;
/**
* Default constructor. The key constructed must have its key
* and algorithm initialized before it may be used, for example
* by using <code>decode</code>.
*/
public X509Key() { }
/*
* Build and initialize as a "default" key. All X.509 key
* data is stored and transmitted losslessly, but no knowledge
* about this particular algorithm is available.
*/
private X509Key(AlgorithmId algid, BitArray key)
throws InvalidKeyException {
this.algid = algid;
setKey(key);
encode();
}
/**
* Sets the key in the BitArray form.
*/
protected void setKey(BitArray key) {
this.bitStringKey = (BitArray)key.clone();
/*
* Do this to keep the byte array form consistent with
* this. Can delete when byte[] key is deleted.
*/
this.key = key.toByteArray();
int remaining = key.length() % 8;
this.unusedBits =
((remaining == 0) ? 0 : 8 - remaining);
}
/**
* Gets the key. The key may or may not be byte aligned.
* @return a BitArray containing the key.
*/
protected BitArray getKey() {
/*
* Do this for consistency in case a subclass
* modifies byte[] key directly. Remove when
* byte[] key is deleted.
* Note: the consistency checks fail when the subclass
* modifies a non byte-aligned key (into a byte-aligned key)
* using the deprecated byte[] key field.
*/
this.bitStringKey = new BitArray(
this.key.length * 8 - this.unusedBits,
this.key);
return (BitArray)bitStringKey.clone();
}
/**
* 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.
*
* <P>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.
*
* @param in the DER-encoded SubjectPublicKeyInfo value
* @exception IOException on data format errors
*/
public static PublicKey parse(DerValue in) throws IOException
{
AlgorithmId algorithm;
PublicKey subjectKey;
if (in.tag != DerValue.tag_Sequence)
throw new IOException("corrupt subject key");
algorithm = AlgorithmId.parse(in.data.getDerValue());
try {
subjectKey = buildX509Key(algorithm,
in.data.getUnalignedBitString());
} catch (InvalidKeyException e) {
throw new IOException("subject key, " + e.getMessage(), e);
}
if (in.data.available() != 0)
throw new IOException("excess subject key");
return subjectKey;
}
/**
* 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 <code>key</code> bits; Diffie-Hellman and
* DSS/DSA keys encapsulate a single unsigned integer.
*
* <P>This function is called when creating X.509 SubjectPublicKeyInfo
* values using the X509Key member functions, such as <code>parse</code>
* and <code>decode</code>.
*
* @exception IOException on parsing errors.
* @exception InvalidKeyException on invalid key encodings.
*/
protected void parseKeyBits() throws IOException, InvalidKeyException {
encode();
}
/*
* Factory interface, building the kind of key associated with this
* specific algorithm ID or else returning this generic base class.
* See the description above.
*/
static PublicKey buildX509Key(AlgorithmId algid, BitArray key)
throws IOException, InvalidKeyException
{
/*
* Use the algid and key parameters to produce the ASN.1 encoding
* of the key, which will then be used as the input to the
* key factory.
*/
DerOutputStream x509EncodedKeyStream = new DerOutputStream();
encode(x509EncodedKeyStream, algid, key);
X509EncodedKeySpec x509KeySpec
= new X509EncodedKeySpec(x509EncodedKeyStream.toByteArray());
try {
// Instantiate the key factory of the appropriate algorithm
KeyFactory keyFac = KeyFactory.getInstance(algid.getName());
// Generate the public key
return keyFac.generatePublic(x509KeySpec);
} catch (NoSuchAlgorithmException e) {
// Return generic X509Key with opaque key data (see below)
} catch (InvalidKeySpecException e) {
throw new InvalidKeyException(e.getMessage(), e);
}
/*
* Try again using JDK1.1-style for backwards compatibility.
*/
String classname = "";
try {
Properties props;
String keytype;
Provider sunProvider;
sunProvider = Security.getProvider("SUN");
if (sunProvider == null)
throw new InstantiationException();
classname = sunProvider.getProperty("PublicKey.X.509." +
algid.getName());
if (classname == null) {
throw new InstantiationException();
}
Class keyClass = null;
try {
keyClass = Class.forName(classname);
} catch (ClassNotFoundException e) {
ClassLoader cl = ClassLoader.getSystemClassLoader();
if (cl != null) {
keyClass = cl.loadClass(classname);
}
}
Object inst = null;
X509Key result;
if (keyClass != null)
inst = keyClass.newInstance();
if (inst instanceof X509Key) {
result = (X509Key) inst;
result.algid = algid;
result.setKey(key);
result.parseKeyBits();
return result;
}
} catch (ClassNotFoundException e) {
} catch (InstantiationException e) {
} catch (IllegalAccessException e) {
// this should not happen.
throw new IOException (classname + " [internal error]");
}
X509Key result = new X509Key(algid, key);
return result;
}
/**
* Returns the algorithm to be used with this key.
*/
public String getAlgorithm() {
return algid.getName();
}
/**
* Returns the algorithm ID to be used with this key.
*/
public AlgorithmId getAlgorithmId() { return algid; }
/**
* Encode SubjectPublicKeyInfo sequence on the DER output stream.
*
* @exception IOException on encoding errors.
*/
public final void encode(DerOutputStream out) throws IOException
{
encode(out, this.algid, getKey());
}
/**
* Returns the DER-encoded form of the key as a byte array.
*/
public byte[] getEncoded() {
try {
return getEncodedInternal().clone();
} catch (InvalidKeyException e) {
// XXX
}
return null;
}
public byte[] getEncodedInternal() throws InvalidKeyException {
byte[] encoded = encodedKey;
if (encoded == null) {
try {
DerOutputStream out = new DerOutputStream();
encode(out);
encoded = out.toByteArray();
} catch (IOException e) {
throw new InvalidKeyException("IOException : " +
e.getMessage());
}
encodedKey = encoded;
}
return encoded;
}
/**
* Returns the format for this key: "X.509"
*/
public String getFormat() {
return "X.509";
}
/**
* Returns the DER-encoded form of the key as a byte array.
*
* @exception InvalidKeyException on encoding errors.
*/
public byte[] encode() throws InvalidKeyException {
return getEncodedInternal().clone();
}
/*
* Returns a printable representation of the key
*/
public String toString()
{
HexDumpEncoder encoder = new HexDumpEncoder();
return "algorithm = " + algid.toString()
+ ", unparsed keybits = \n" + encoder.encodeBuffer(key);
}
/**
* Initialize an X509Key object from an input stream. The data on that
* input stream must be encoded using DER, obeying the X.509
* <code>SubjectPublicKeyInfo</code> 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.)
*
* <P>Subclasses should not normally redefine this method; they should
* instead provide a <code>parseKeyBits</code> method to parse any
* fields inside the <code>key</code> member.
*
* <P>The exception to this rule is that since private keys need not
* be encoded using the X.509 <code>SubjectPublicKeyInfo</code> format,
* private keys may override this method, <code>encode</code>, and
* of course <code>getFormat</code>.
*
* @param in an input stream with a DER-encoded X.509
* SubjectPublicKeyInfo value
* @exception InvalidKeyException on parsing errors.
*/
public void decode(InputStream in)
throws InvalidKeyException
{
DerValue val;
try {
val = new DerValue(in);
if (val.tag != DerValue.tag_Sequence)
throw new InvalidKeyException("invalid key format");
algid = AlgorithmId.parse(val.data.getDerValue());
setKey(val.data.getUnalignedBitString());
parseKeyBits();
if (val.data.available() != 0)
throw new InvalidKeyException ("excess key data");
} catch (IOException e) {
// e.printStackTrace ();
throw new InvalidKeyException("IOException: " +
e.getMessage());
}
}
public void decode(byte[] encodedKey) throws InvalidKeyException {
decode(new ByteArrayInputStream(encodedKey));
}
/**
* Serialization write ... X.509 keys serialize as
* themselves, and they're parsed when they get read back.
*/
private void writeObject(ObjectOutputStream stream) throws IOException {
stream.write(getEncoded());
}
/**
* Serialization read ... X.509 keys serialize as
* themselves, and they're parsed when they get read back.
*/
private void readObject(ObjectInputStream stream) throws IOException {
try {
decode(stream);
} catch (InvalidKeyException e) {
e.printStackTrace();
throw new IOException("deserialized key is invalid: " +
e.getMessage());
}
}
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj instanceof Key == false) {
return false;
}
try {
byte[] thisEncoded = this.getEncodedInternal();
byte[] otherEncoded;
if (obj instanceof X509Key) {
otherEncoded = ((X509Key)obj).getEncodedInternal();
} else {
otherEncoded = ((Key)obj).getEncoded();
}
return Arrays.equals(thisEncoded, otherEncoded);
} catch (InvalidKeyException e) {
return false;
}
}
/**
* Calculates a hash code value for the object. Objects
* which are equal will also have the same hashcode.
*/
public int hashCode() {
try {
byte[] b1 = getEncodedInternal();
int r = b1.length;
for (int i = 0; i < b1.length; i++) {
r += (b1[i] & 0xff) * 37;
}
return r;
} catch (InvalidKeyException e) {
// should not happen
return 0;
}
}
/*
* Produce SubjectPublicKey encoding from algorithm id and key material.
*/
static void encode(DerOutputStream out, AlgorithmId algid, BitArray key)
throws IOException {
DerOutputStream tmp = new DerOutputStream();
algid.encode(tmp);
tmp.putUnalignedBitString(key);
out.write(DerValue.tag_Sequence, tmp);
}
}