package org.bouncycastle.pqc.jcajce.provider.mceliece;
import java.io.IOException;
import java.math.BigInteger;
import java.security.InvalidKeyException;
import java.security.Key;
import java.security.KeyFactorySpi;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.KeySpec;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import org.bouncycastle.asn1.ASN1Integer;
import org.bouncycastle.asn1.ASN1ObjectIdentifier;
import org.bouncycastle.asn1.ASN1OctetString;
import org.bouncycastle.asn1.ASN1Primitive;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.pkcs.PrivateKeyInfo;
import org.bouncycastle.asn1.x509.SubjectPublicKeyInfo;
import org.bouncycastle.pqc.asn1.McEliecePrivateKey;
import org.bouncycastle.pqc.asn1.McEliecePublicKey;
import org.bouncycastle.pqc.jcajce.spec.McEliecePrivateKeySpec;
import org.bouncycastle.pqc.jcajce.spec.McEliecePublicKeySpec;
/**
* This class is used to translate between McEliece keys and key specifications.
*
* @see BCMcEliecePrivateKey
* @see McEliecePrivateKeySpec
* @see BCMcEliecePublicKey
* @see McEliecePublicKeySpec
*/
public class McElieceKeyFactorySpi
extends KeyFactorySpi
{
/**
* The OID of the algorithm.
*/
public static final String OID = "1.3.6.1.4.1.8301.3.1.3.4.1";
/**
* Converts, if possible, a key specification into a
* {@link BCMcEliecePublicKey}. Currently, the following key specifications
* are supported: {@link McEliecePublicKeySpec}, {@link X509EncodedKeySpec}.
*
* @param keySpec the key specification
* @return the McEliece public key
* @throws InvalidKeySpecException if the key specification is not supported.
*/
public PublicKey generatePublic(KeySpec keySpec)
throws InvalidKeySpecException
{
if (keySpec instanceof McEliecePublicKeySpec)
{
return new BCMcEliecePublicKey((McEliecePublicKeySpec)keySpec);
}
else if (keySpec instanceof X509EncodedKeySpec)
{
// get the DER-encoded Key according to X.509 from the spec
byte[] encKey = ((X509EncodedKeySpec)keySpec).getEncoded();
// decode the SubjectPublicKeyInfo data structure to the pki object
SubjectPublicKeyInfo pki;
try
{
pki = SubjectPublicKeyInfo.getInstance(ASN1Primitive.fromByteArray(encKey));
}
catch (IOException e)
{
throw new InvalidKeySpecException(e.toString());
}
try
{
// --- Build and return the actual key.
ASN1Primitive innerType = pki.parsePublicKey();
ASN1Sequence publicKey = (ASN1Sequence)innerType;
// decode oidString (but we don't need it right now)
String oidString = ((ASN1ObjectIdentifier)publicKey.getObjectAt(0))
.toString();
// decode <n>
BigInteger bigN = ((ASN1Integer)publicKey.getObjectAt(1)).getValue();
int n = bigN.intValue();
// decode <t>
BigInteger bigT = ((ASN1Integer)publicKey.getObjectAt(2)).getValue();
int t = bigT.intValue();
// decode <matrixG>
byte[] matrixG = ((ASN1OctetString)publicKey.getObjectAt(3)).getOctets();
return new BCMcEliecePublicKey(new McEliecePublicKeySpec(OID, t, n,
matrixG));
}
catch (IOException cce)
{
throw new InvalidKeySpecException(
"Unable to decode X509EncodedKeySpec: "
+ cce.getMessage());
}
}
throw new InvalidKeySpecException("Unsupported key specification: "
+ keySpec.getClass() + ".");
}
/**
* Converts, if possible, a key specification into a
* {@link BCMcEliecePrivateKey}. Currently, the following key specifications
* are supported: {@link McEliecePrivateKeySpec},
* {@link PKCS8EncodedKeySpec}.
*
* @param keySpec the key specification
* @return the McEliece private key
* @throws InvalidKeySpecException if the KeySpec is not supported.
*/
public PrivateKey generatePrivate(KeySpec keySpec)
throws InvalidKeySpecException
{
if (keySpec instanceof McEliecePrivateKeySpec)
{
return new BCMcEliecePrivateKey((McEliecePrivateKeySpec)keySpec);
}
else if (keySpec instanceof PKCS8EncodedKeySpec)
{
// get the DER-encoded Key according to PKCS#8 from the spec
byte[] encKey = ((PKCS8EncodedKeySpec)keySpec).getEncoded();
// decode the PKCS#8 data structure to the pki object
PrivateKeyInfo pki;
try
{
pki = PrivateKeyInfo.getInstance(ASN1Primitive.fromByteArray(encKey));
}
catch (IOException e)
{
throw new InvalidKeySpecException("Unable to decode PKCS8EncodedKeySpec: " + e);
}
try
{
ASN1Primitive innerType = pki.parsePrivateKey().toASN1Primitive();
// build and return the actual key
ASN1Sequence privKey = (ASN1Sequence)innerType;
// decode oidString (but we don't need it right now)
String oidString = ((ASN1ObjectIdentifier)privKey.getObjectAt(0))
.toString();
// decode <n>
BigInteger bigN = ((ASN1Integer)privKey.getObjectAt(1)).getValue();
int n = bigN.intValue();
// decode <k>
BigInteger bigK = ((ASN1Integer)privKey.getObjectAt(2)).getValue();
int k = bigK.intValue();
// decode <fieldPoly>
byte[] encFieldPoly = ((ASN1OctetString)privKey.getObjectAt(3))
.getOctets();
// decode <goppaPoly>
byte[] encGoppaPoly = ((ASN1OctetString)privKey.getObjectAt(4))
.getOctets();
// decode <sInv>
byte[] encSInv = ((ASN1OctetString)privKey.getObjectAt(5)).getOctets();
// decode <p1>
byte[] encP1 = ((ASN1OctetString)privKey.getObjectAt(6)).getOctets();
// decode <p2>
byte[] encP2 = ((ASN1OctetString)privKey.getObjectAt(7)).getOctets();
//decode <h>
byte[] encH = ((ASN1OctetString)privKey.getObjectAt(8)).getOctets();
// decode <qInv>
ASN1Sequence qSeq = (ASN1Sequence)privKey.getObjectAt(9);
byte[][] encQInv = new byte[qSeq.size()][];
for (int i = 0; i < qSeq.size(); i++)
{
encQInv[i] = ((ASN1OctetString)qSeq.getObjectAt(i)).getOctets();
}
return new BCMcEliecePrivateKey(new McEliecePrivateKeySpec(OID, n, k,
encFieldPoly, encGoppaPoly, encSInv, encP1, encP2,
encH, encQInv));
}
catch (IOException cce)
{
throw new InvalidKeySpecException(
"Unable to decode PKCS8EncodedKeySpec.");
}
}
throw new InvalidKeySpecException("Unsupported key specification: "
+ keySpec.getClass() + ".");
}
/**
* Converts, if possible, a given key into a key specification. Currently,
* the following key specifications are supported:
* <ul>
* <li>for McEliecePublicKey: {@link X509EncodedKeySpec},
* {@link McEliecePublicKeySpec}</li>
* <li>for McEliecePrivateKey: {@link PKCS8EncodedKeySpec},
* {@link McEliecePrivateKeySpec}</li>.
* </ul>
*
* @param key the key
* @param keySpec the key specification
* @return the specification of the McEliece key
* @throws InvalidKeySpecException if the key type or the key specification is not
* supported.
* @see BCMcEliecePrivateKey
* @see McEliecePrivateKeySpec
* @see BCMcEliecePublicKey
* @see McEliecePublicKeySpec
*/
public KeySpec getKeySpec(Key key, Class keySpec)
throws InvalidKeySpecException
{
if (key instanceof BCMcEliecePrivateKey)
{
if (PKCS8EncodedKeySpec.class.isAssignableFrom(keySpec))
{
return new PKCS8EncodedKeySpec(key.getEncoded());
}
else if (McEliecePrivateKeySpec.class.isAssignableFrom(keySpec))
{
BCMcEliecePrivateKey privKey = (BCMcEliecePrivateKey)key;
return new McEliecePrivateKeySpec(OID, privKey.getN(), privKey
.getK(), privKey.getField(), privKey.getGoppaPoly(),
privKey.getSInv(), privKey.getP1(), privKey.getP2(),
privKey.getH(), privKey.getQInv());
}
}
else if (key instanceof BCMcEliecePublicKey)
{
if (X509EncodedKeySpec.class.isAssignableFrom(keySpec))
{
return new X509EncodedKeySpec(key.getEncoded());
}
else if (McEliecePublicKeySpec.class.isAssignableFrom(keySpec))
{
BCMcEliecePublicKey pubKey = (BCMcEliecePublicKey)key;
return new McEliecePublicKeySpec(OID, pubKey.getN(), pubKey.getT(),
pubKey.getG());
}
}
else
{
throw new InvalidKeySpecException("Unsupported key type: "
+ key.getClass() + ".");
}
throw new InvalidKeySpecException("Unknown key specification: "
+ keySpec + ".");
}
/**
* Translates a key into a form known by the FlexiProvider. Currently, only
* the following "source" keys are supported: {@link BCMcEliecePrivateKey},
* {@link BCMcEliecePublicKey}.
*
* @param key the key
* @return a key of a known key type
* @throws InvalidKeyException if the key type is not supported.
*/
public Key translateKey(Key key)
throws InvalidKeyException
{
if ((key instanceof BCMcEliecePrivateKey)
|| (key instanceof BCMcEliecePublicKey))
{
return key;
}
throw new InvalidKeyException("Unsupported key type.");
}
public PublicKey generatePublic(SubjectPublicKeyInfo pki)
throws InvalidKeySpecException
{
// get the inner type inside the BIT STRING
try
{
ASN1Primitive innerType = pki.parsePublicKey();
McEliecePublicKey key = McEliecePublicKey.getInstance(innerType);
return new BCMcEliecePublicKey(key.getOID().getId(), key.getN(), key.getT(), key.getG());
}
catch (IOException cce)
{
throw new InvalidKeySpecException("Unable to decode X509EncodedKeySpec");
}
}
public PrivateKey generatePrivate(PrivateKeyInfo pki)
throws InvalidKeySpecException
{
// get the inner type inside the BIT STRING
try
{
ASN1Primitive innerType = pki.parsePrivateKey().toASN1Primitive();
McEliecePrivateKey key = McEliecePrivateKey.getInstance(innerType);
return new BCMcEliecePrivateKey(key.getOID().getId(), key.getN(), key.getK(), key.getField(), key.getGoppaPoly(), key.getSInv(), key.getP1(), key.getP2(), key.getH(), key.getQInv());
}
catch (IOException cce)
{
throw new InvalidKeySpecException("Unable to decode PKCS8EncodedKeySpec");
}
}
protected PublicKey engineGeneratePublic(KeySpec keySpec)
throws InvalidKeySpecException
{
return null; //To change body of implemented methods use File | Settings | File Templates.
}
protected PrivateKey engineGeneratePrivate(KeySpec keySpec)
throws InvalidKeySpecException
{
return null; //To change body of implemented methods use File | Settings | File Templates.
}
protected KeySpec engineGetKeySpec(Key key, Class tClass)
throws InvalidKeySpecException
{
return null; //To change body of implemented methods use File | Settings | File Templates.
}
protected Key engineTranslateKey(Key key)
throws InvalidKeyException
{
return null; //To change body of implemented methods use File | Settings | File Templates.
}
}