ojluni/src/main/java/sun/security/ec/ECParameters.java - platform/libcore.git - Git at Google

 /*
  * Copyright (c) 2006, Oracle and/or its affiliates. All rights reserved.
  * 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).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  */

 package sun.security.ec;

 import java.io.IOException;
 import java.math.BigInteger;

 import java.security.*;
 import java.security.spec.*;

 import sun.security.util.*;

 /**
  * This class implements encoding and decoding of Elliptic Curve parameters
  * as specified in RFC 3279.
  *
  * However, only named curves are currently supported.
  *
  * ASN.1 from RFC 3279 follows. Note that X9.62 (2005) has added some additional
  * options.
  *
  * <pre>
  *    EcpkParameters ::= CHOICE {
  *      ecParameters  ECParameters,
  *      namedCurve    OBJECT IDENTIFIER,
  *      implicitlyCA  NULL }
  *
  *    ECParameters ::= SEQUENCE {
  *       version   ECPVer,          -- version is always 1
  *       fieldID   FieldID,         -- identifies the finite field over
  *                                  -- which the curve is defined
  *       curve     Curve,           -- coefficients a and b of the
  *                                  -- elliptic curve
  *       base      ECPoint,         -- specifies the base point P
  *                                  -- on the elliptic curve
  *       order     INTEGER,         -- the order n of the base point
  *       cofactor  INTEGER OPTIONAL -- The integer h = #E(Fq)/n
  *       }
  *
  *    ECPVer ::= INTEGER {ecpVer1(1)}
  *
  *    Curve ::= SEQUENCE {
  *       a         FieldElement,
  *       b         FieldElement,
  *       seed      BIT STRING OPTIONAL }
  *
  *    FieldElement ::= OCTET STRING
  *
  *    ECPoint ::= OCTET STRING
  * </pre>
  *
  * @since   1.6
  * @author  Andreas Sterbenz
  */
 public final class ECParameters extends AlgorithmParametersSpi {

     public ECParameters() {
         // empty
     }

     // Used by SunPKCS11 and SunJSSE.
     public static ECPoint decodePoint(byte[] data, EllipticCurve curve)
             throws IOException {
         if ((data.length == 0) || (data[0] != 4)) {
             throw new IOException("Only uncompressed point format supported");
         }
         int n = (curve.getField().getFieldSize() + 7 ) >> 3;
         if (data.length != (n * 2) + 1) {
             throw new IOException("Point does not match field size");
         }
         byte[] xb = new byte[n];
         byte[] yb = new byte[n];
         System.arraycopy(data, 1, xb, 0, n);
         System.arraycopy(data, n + 1, yb, 0, n);
         return new ECPoint(new BigInteger(1, xb), new BigInteger(1, yb));
     }

     // Used by SunPKCS11 and SunJSSE.
     public static byte[] encodePoint(ECPoint point, EllipticCurve curve) {
         // get field size in bytes (rounding up)
         int n = (curve.getField().getFieldSize() + 7) >> 3;
         byte[] xb = trimZeroes(point.getAffineX().toByteArray());
         byte[] yb = trimZeroes(point.getAffineY().toByteArray());
         if ((xb.length > n) || (yb.length > n)) {
             throw new RuntimeException
                 ("Point coordinates do not match field size");
         }
         byte[] b = new byte[1 + (n << 1)];
         b[0] = 4; // uncompressed
         System.arraycopy(xb, 0, b, n - xb.length + 1, xb.length);
         System.arraycopy(yb, 0, b, b.length - yb.length, yb.length);
         return b;
     }

     // Copied from the SunPKCS11 code - should be moved to a common location.
     // trim leading (most significant) zeroes from the result
     static byte[] trimZeroes(byte[] b) {
         int i = 0;
         while ((i < b.length - 1) && (b[i] == 0)) {
             i++;
         }
         if (i == 0) {
             return b;
         }
         byte[] t = new byte[b.length - i];
         System.arraycopy(b, i, t, 0, t.length);
         return t;
     }

     // Convert the given ECParameterSpec object to a NamedCurve object.
     // If params does not represent a known named curve, return null.
     // Used by SunPKCS11.
     public static NamedCurve getNamedCurve(ECParameterSpec params) {
         if ((params instanceof NamedCurve) || (params == null)) {
             return (NamedCurve)params;
         }
         // This is a hack to allow SunJSSE to work with 3rd party crypto
         // providers for ECC and not just SunPKCS11.
         // This can go away once we decide how to expose curve names in the
         // public API.
         // Note that it assumes that the 3rd party provider encodes named
         // curves using the short form, not explicitly. If it did that, then
         // the SunJSSE TLS ECC extensions are wrong, which could lead to
         // interoperability problems.
         int fieldSize = params.getCurve().getField().getFieldSize();
         for (ECParameterSpec namedCurve : NamedCurve.knownECParameterSpecs()) {
             // ECParameterSpec does not define equals, so check all the
             // components ourselves.
             // Quick field size check first
             if (namedCurve.getCurve().getField().getFieldSize() != fieldSize) {
                 continue;
             }
             if (namedCurve.getCurve().equals(params.getCurve()) == false) {
                 continue;
             }
             if (namedCurve.getGenerator().equals(params.getGenerator()) == false) {
                 continue;
             }
             if (namedCurve.getOrder().equals(params.getOrder()) == false) {
                 continue;
             }
             if (namedCurve.getCofactor() != params.getCofactor()) {
                 continue;
             }
             // everything matches our named curve, return it
             return (NamedCurve)namedCurve;
         }
         // no match found
         return null;
     }

     // Used by SunJSSE.
     public static String getCurveName(ECParameterSpec params) {
         NamedCurve curve = getNamedCurve(params);
         return (curve == null) ? null : curve.getObjectIdentifier().toString();
     }

     // Used by SunPKCS11.
     public static byte[] encodeParameters(ECParameterSpec params) {
         NamedCurve curve = getNamedCurve(params);
         if (curve == null) {
             throw new RuntimeException("Not a known named curve: " + params);
         }
         return curve.getEncoded();
     }

     // Used by SunPKCS11.
     public static ECParameterSpec decodeParameters(byte[] params) throws IOException {
         DerValue encodedParams = new DerValue(params);
         if (encodedParams.tag == DerValue.tag_ObjectId) {
             ObjectIdentifier oid = encodedParams.getOID();
             ECParameterSpec spec = NamedCurve.getECParameterSpec(oid);
             if (spec == null) {
                 throw new IOException("Unknown named curve: " + oid);
             }
             return spec;
         }

         throw new IOException("Only named ECParameters supported");

         // The code below is incomplete.
         // It is left as a starting point for a complete parsing implementation.

 /*
         if (encodedParams.tag != DerValue.tag_Sequence) {
             throw new IOException("Unsupported EC parameters, tag: " + encodedParams.tag);
         }

         encodedParams.data.reset();

         DerInputStream in = encodedParams.data;

         int version = in.getInteger();
         if (version != 1) {
             throw new IOException("Unsupported EC parameters version: " + version);
         }
         ECField field = parseField(in);
         EllipticCurve curve = parseCurve(in, field);
         ECPoint point = parsePoint(in, curve);

         BigInteger order = in.getBigInteger();
         int cofactor = 0;

         if (in.available() != 0) {
             cofactor = in.getInteger();
         }

         // XXX HashAlgorithm optional

         if (encodedParams.data.available() != 0) {
             throw new IOException("encoded params have " +
                                   encodedParams.data.available() +
                                   " extra bytes");
         }

         return new ECParameterSpec(curve, point, order, cofactor);
 */
     }

 /*
     private static final ObjectIdentifier fieldTypePrime =
         ObjectIdentifier.newInternal(new int[] {1, 2, 840, 10045, 1, 1});

     private static final ObjectIdentifier fieldTypeChar2 =
         ObjectIdentifier.newInternal(new int[] {1, 2, 840, 10045, 1, 2});

     private static ECField parseField(DerInputStream in) throws IOException {
         DerValue v = in.getDerValue();
         ObjectIdentifier oid = v.data.getOID();
         if (oid.equals(fieldTypePrime) == false) {
             throw new IOException("Only prime fields supported: " + oid);
         }
         BigInteger fieldSize = v.data.getBigInteger();
         return new ECFieldFp(fieldSize);
     }

     private static EllipticCurve parseCurve(DerInputStream in, ECField field)
             throws IOException {
         DerValue v = in.getDerValue();
         byte[] ab = v.data.getOctetString();
         byte[] bb = v.data.getOctetString();
         return new EllipticCurve(field, new BigInteger(1, ab), new BigInteger(1, bb));
     }

     private static ECPoint parsePoint(DerInputStream in, EllipticCurve curve)
             throws IOException {
         byte[] data = in.getOctetString();
         return decodePoint(data, curve);
     }
 */

     // used by ECPublicKeyImpl and ECPrivateKeyImpl
     static AlgorithmParameters getAlgorithmParameters(ECParameterSpec spec)
             throws InvalidKeyException {
         try {
             AlgorithmParameters params = AlgorithmParameters.getInstance
                                         ("EC", ECKeyFactory.ecInternalProvider);
             params.init(spec);
             return params;
         } catch (GeneralSecurityException e) {
             throw new InvalidKeyException("EC parameters error", e);
         }
     }

     // AlgorithmParameterSpi methods

     // The parameters these AlgorithmParameters object represents.
     // Currently, it is always an instance of NamedCurve.
     private ECParameterSpec paramSpec;

     protected void engineInit(AlgorithmParameterSpec paramSpec)
             throws InvalidParameterSpecException {
         if (paramSpec instanceof ECParameterSpec) {
             this.paramSpec = getNamedCurve((ECParameterSpec)paramSpec);
             if (this.paramSpec == null) {
                 throw new InvalidParameterSpecException
                     ("Not a supported named curve: " + paramSpec);
             }
         } else if (paramSpec instanceof ECGenParameterSpec) {
             String name = ((ECGenParameterSpec)paramSpec).getName();
             ECParameterSpec spec = NamedCurve.getECParameterSpec(name);
             if (spec == null) {
                 throw new InvalidParameterSpecException("Unknown curve: " + name);
             }
             this.paramSpec = spec;
         } else if (paramSpec == null) {
             throw new InvalidParameterSpecException
                 ("paramSpec must not be null");
         } else {
             throw new InvalidParameterSpecException
                 ("Only ECParameterSpec and ECGenParameterSpec supported");
         }
     }

     protected void engineInit(byte[] params) throws IOException {
         paramSpec = decodeParameters(params);
     }

     protected void engineInit(byte[] params, String decodingMethod) throws IOException {
         engineInit(params);
     }

     protected <T extends AlgorithmParameterSpec> T engineGetParameterSpec(Class<T> spec)
             throws InvalidParameterSpecException {
         if (spec.isAssignableFrom(ECParameterSpec.class)) {
             return (T)paramSpec;
         } else if (spec.isAssignableFrom(ECGenParameterSpec.class)) {
             return (T)new ECGenParameterSpec(getCurveName(paramSpec));
         } else {
             throw new InvalidParameterSpecException
                 ("Only ECParameterSpec and ECGenParameterSpec supported");
         }
     }

     protected byte[] engineGetEncoded() throws IOException {
         return encodeParameters(paramSpec);
     }

     protected byte[] engineGetEncoded(String encodingMethod) throws IOException {
         return engineGetEncoded();
     }

     protected String engineToString() {
         return paramSpec.toString();
     }
 }
	/*
	* Copyright (c) 2006, Oracle and/or its affiliates. All rights reserved.
	* 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).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package sun.security.ec;

	import java.io.IOException;
	import java.math.BigInteger;

	import java.security.*;
	import java.security.spec.*;

	import sun.security.util.*;

	/**
	* This class implements encoding and decoding of Elliptic Curve parameters
	* as specified in RFC 3279.
	*
	* However, only named curves are currently supported.
	*
	* ASN.1 from RFC 3279 follows. Note that X9.62 (2005) has added some additional
	* options.
	*
	* <pre>
	* EcpkParameters ::= CHOICE {
	* ecParameters ECParameters,
	* namedCurve OBJECT IDENTIFIER,
	* implicitlyCA NULL }
	*
	* ECParameters ::= SEQUENCE {
	* version ECPVer, -- version is always 1
	* fieldID FieldID, -- identifies the finite field over
	* -- which the curve is defined
	* curve Curve, -- coefficients a and b of the
	* -- elliptic curve
	* base ECPoint, -- specifies the base point P
	* -- on the elliptic curve
	* order INTEGER, -- the order n of the base point
	* cofactor INTEGER OPTIONAL -- The integer h = #E(Fq)/n
	* }
	*
	* ECPVer ::= INTEGER {ecpVer1(1)}
	*
	* Curve ::= SEQUENCE {
	* a FieldElement,
	* b FieldElement,
	* seed BIT STRING OPTIONAL }
	*
	* FieldElement ::= OCTET STRING
	*
	* ECPoint ::= OCTET STRING
	* </pre>
	*
	* @since 1.6
	* @author Andreas Sterbenz
	*/
	public final class ECParameters extends AlgorithmParametersSpi {

	public ECParameters() {
	// empty
	}

	// Used by SunPKCS11 and SunJSSE.
	public static ECPoint decodePoint(byte[] data, EllipticCurve curve)
	throws IOException {
	if ((data.length == 0) \|\| (data[0] != 4)) {
	throw new IOException("Only uncompressed point format supported");
	}
	int n = (curve.getField().getFieldSize() + 7 ) >> 3;
	if (data.length != (n * 2) + 1) {
	throw new IOException("Point does not match field size");
	}
	byte[] xb = new byte[n];
	byte[] yb = new byte[n];
	System.arraycopy(data, 1, xb, 0, n);
	System.arraycopy(data, n + 1, yb, 0, n);
	return new ECPoint(new BigInteger(1, xb), new BigInteger(1, yb));
	}

	// Used by SunPKCS11 and SunJSSE.
	public static byte[] encodePoint(ECPoint point, EllipticCurve curve) {
	// get field size in bytes (rounding up)
	int n = (curve.getField().getFieldSize() + 7) >> 3;
	byte[] xb = trimZeroes(point.getAffineX().toByteArray());
	byte[] yb = trimZeroes(point.getAffineY().toByteArray());
	if ((xb.length > n) \|\| (yb.length > n)) {
	throw new RuntimeException
	("Point coordinates do not match field size");
	}
	byte[] b = new byte[1 + (n << 1)];
	b[0] = 4; // uncompressed
	System.arraycopy(xb, 0, b, n - xb.length + 1, xb.length);
	System.arraycopy(yb, 0, b, b.length - yb.length, yb.length);
	return b;
	}

	// Copied from the SunPKCS11 code - should be moved to a common location.
	// trim leading (most significant) zeroes from the result
	static byte[] trimZeroes(byte[] b) {
	int i = 0;
	while ((i < b.length - 1) && (b[i] == 0)) {
	i++;
	}
	if (i == 0) {
	return b;
	}
	byte[] t = new byte[b.length - i];
	System.arraycopy(b, i, t, 0, t.length);
	return t;
	}

	// Convert the given ECParameterSpec object to a NamedCurve object.
	// If params does not represent a known named curve, return null.
	// Used by SunPKCS11.
	public static NamedCurve getNamedCurve(ECParameterSpec params) {
	if ((params instanceof NamedCurve) \|\| (params == null)) {
	return (NamedCurve)params;
	}
	// This is a hack to allow SunJSSE to work with 3rd party crypto
	// providers for ECC and not just SunPKCS11.
	// This can go away once we decide how to expose curve names in the
	// public API.
	// Note that it assumes that the 3rd party provider encodes named
	// curves using the short form, not explicitly. If it did that, then
	// the SunJSSE TLS ECC extensions are wrong, which could lead to
	// interoperability problems.
	int fieldSize = params.getCurve().getField().getFieldSize();
	for (ECParameterSpec namedCurve : NamedCurve.knownECParameterSpecs()) {
	// ECParameterSpec does not define equals, so check all the
	// components ourselves.
	// Quick field size check first
	if (namedCurve.getCurve().getField().getFieldSize() != fieldSize) {
	continue;
	}
	if (namedCurve.getCurve().equals(params.getCurve()) == false) {
	continue;
	}
	if (namedCurve.getGenerator().equals(params.getGenerator()) == false) {
	continue;
	}
	if (namedCurve.getOrder().equals(params.getOrder()) == false) {
	continue;
	}
	if (namedCurve.getCofactor() != params.getCofactor()) {
	continue;
	}
	// everything matches our named curve, return it
	return (NamedCurve)namedCurve;
	}
	// no match found
	return null;
	}

	// Used by SunJSSE.
	public static String getCurveName(ECParameterSpec params) {
	NamedCurve curve = getNamedCurve(params);
	return (curve == null) ? null : curve.getObjectIdentifier().toString();
	}

	// Used by SunPKCS11.
	public static byte[] encodeParameters(ECParameterSpec params) {
	NamedCurve curve = getNamedCurve(params);
	if (curve == null) {
	throw new RuntimeException("Not a known named curve: " + params);
	}
	return curve.getEncoded();
	}

	// Used by SunPKCS11.
	public static ECParameterSpec decodeParameters(byte[] params) throws IOException {
	DerValue encodedParams = new DerValue(params);
	if (encodedParams.tag == DerValue.tag_ObjectId) {
	ObjectIdentifier oid = encodedParams.getOID();
	ECParameterSpec spec = NamedCurve.getECParameterSpec(oid);
	if (spec == null) {
	throw new IOException("Unknown named curve: " + oid);
	}
	return spec;
	}

	throw new IOException("Only named ECParameters supported");

	// The code below is incomplete.
	// It is left as a starting point for a complete parsing implementation.

	/*
	if (encodedParams.tag != DerValue.tag_Sequence) {
	throw new IOException("Unsupported EC parameters, tag: " + encodedParams.tag);
	}

	encodedParams.data.reset();

	DerInputStream in = encodedParams.data;

	int version = in.getInteger();
	if (version != 1) {
	throw new IOException("Unsupported EC parameters version: " + version);
	}
	ECField field = parseField(in);
	EllipticCurve curve = parseCurve(in, field);
	ECPoint point = parsePoint(in, curve);

	BigInteger order = in.getBigInteger();
	int cofactor = 0;

	if (in.available() != 0) {
	cofactor = in.getInteger();
	}

	// XXX HashAlgorithm optional

	if (encodedParams.data.available() != 0) {
	throw new IOException("encoded params have " +
	encodedParams.data.available() +
	" extra bytes");
	}

	return new ECParameterSpec(curve, point, order, cofactor);
	*/
	}

	/*
	private static final ObjectIdentifier fieldTypePrime =
	ObjectIdentifier.newInternal(new int[] {1, 2, 840, 10045, 1, 1});

	private static final ObjectIdentifier fieldTypeChar2 =
	ObjectIdentifier.newInternal(new int[] {1, 2, 840, 10045, 1, 2});

	private static ECField parseField(DerInputStream in) throws IOException {
	DerValue v = in.getDerValue();
	ObjectIdentifier oid = v.data.getOID();
	if (oid.equals(fieldTypePrime) == false) {
	throw new IOException("Only prime fields supported: " + oid);
	}
	BigInteger fieldSize = v.data.getBigInteger();
	return new ECFieldFp(fieldSize);
	}

	private static EllipticCurve parseCurve(DerInputStream in, ECField field)
	throws IOException {
	DerValue v = in.getDerValue();
	byte[] ab = v.data.getOctetString();
	byte[] bb = v.data.getOctetString();
	return new EllipticCurve(field, new BigInteger(1, ab), new BigInteger(1, bb));
	}

	private static ECPoint parsePoint(DerInputStream in, EllipticCurve curve)
	throws IOException {
	byte[] data = in.getOctetString();
	return decodePoint(data, curve);
	}
	*/

	// used by ECPublicKeyImpl and ECPrivateKeyImpl
	static AlgorithmParameters getAlgorithmParameters(ECParameterSpec spec)
	throws InvalidKeyException {
	try {
	AlgorithmParameters params = AlgorithmParameters.getInstance
	("EC", ECKeyFactory.ecInternalProvider);
	params.init(spec);
	return params;
	} catch (GeneralSecurityException e) {
	throw new InvalidKeyException("EC parameters error", e);
	}
	}

	// AlgorithmParameterSpi methods

	// The parameters these AlgorithmParameters object represents.
	// Currently, it is always an instance of NamedCurve.
	private ECParameterSpec paramSpec;

	protected void engineInit(AlgorithmParameterSpec paramSpec)
	throws InvalidParameterSpecException {
	if (paramSpec instanceof ECParameterSpec) {
	this.paramSpec = getNamedCurve((ECParameterSpec)paramSpec);
	if (this.paramSpec == null) {
	throw new InvalidParameterSpecException
	("Not a supported named curve: " + paramSpec);
	}
	} else if (paramSpec instanceof ECGenParameterSpec) {
	String name = ((ECGenParameterSpec)paramSpec).getName();
	ECParameterSpec spec = NamedCurve.getECParameterSpec(name);
	if (spec == null) {
	throw new InvalidParameterSpecException("Unknown curve: " + name);
	}
	this.paramSpec = spec;
	} else if (paramSpec == null) {
	throw new InvalidParameterSpecException
	("paramSpec must not be null");
	} else {
	throw new InvalidParameterSpecException
	("Only ECParameterSpec and ECGenParameterSpec supported");
	}
	}

	protected void engineInit(byte[] params) throws IOException {
	paramSpec = decodeParameters(params);
	}

	protected void engineInit(byte[] params, String decodingMethod) throws IOException {
	engineInit(params);
	}

	protected <T extends AlgorithmParameterSpec> T engineGetParameterSpec(Class<T> spec)
	throws InvalidParameterSpecException {
	if (spec.isAssignableFrom(ECParameterSpec.class)) {
	return (T)paramSpec;
	} else if (spec.isAssignableFrom(ECGenParameterSpec.class)) {
	return (T)new ECGenParameterSpec(getCurveName(paramSpec));
	} else {
	throw new InvalidParameterSpecException
	("Only ECParameterSpec and ECGenParameterSpec supported");
	}
	}

	protected byte[] engineGetEncoded() throws IOException {
	return encodeParameters(paramSpec);
	}

	protected byte[] engineGetEncoded(String encodingMethod) throws IOException {
	return engineGetEncoded();
	}

	protected String engineToString() {
	return paramSpec.toString();
	}
	}