/*

 * Copyright 2003-2006 Sun Microsystems, Inc.  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.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package sun.security.pkcs11;

import java.io.*;

import java.math.BigInteger;

import java.util.*;

import java.security.*;

import java.security.interfaces.*;

import java.security.spec.*;

import javax.crypto.*;

import javax.crypto.interfaces.*;

import javax.crypto.spec.*;

import sun.security.rsa.RSAPublicKeyImpl;

import sun.security.internal.interfaces.TlsMasterSecret;

import sun.security.pkcs11.wrapper.*;

import static sun.security.pkcs11.wrapper.PKCS11Constants.*;

/**

 * Key implementation classes.

 *

 * In PKCS#11, the components of private and secret keys may or may not

 * be accessible. If they are, we use the algorithm specific key classes

 * (e.g. DSAPrivateKey) for compatibility with existing applications.

 * If the components are not accessible, we use a generic class that

 * only implements PrivateKey (or SecretKey). Whether the components of a

 * key are extractable is automatically determined when the key object is

 * created.

 *

 * @author  Andreas Sterbenz

 * @since   1.5

 */

abstract class P11Key implements Key {

    private final static String PUBLIC = "public";

    private final static String PRIVATE = "private";

    private final static String SECRET = "secret";

    // type of key, one of (PUBLIC, PRIVATE, SECRET)

    final String type;

    // session in which the key was created, relevant for session objects

    final Session session;

    // token instance

    final Token token;

    // algorithm name, returned by getAlgorithm(), etc.

    final String algorithm;

    // key id

    final long keyID;

    // effective key length of the key, e.g. 56 for a DES key

    final int keyLength;

    // flags indicating whether the key is a token object, sensitive, extractable

    final boolean tokenObject, sensitive, extractable;

    P11Key(String type, Session session, long keyID, String algorithm,

            int keyLength, CK_ATTRIBUTE[] attributes) {

        this.type = type;

        this.session = session;

        this.token = session.token;

        this.keyID = keyID;

        this.algorithm = algorithm;

        this.keyLength = keyLength;

        boolean tokenObject = false;

        boolean sensitive = false;

        boolean extractable = true;

        int n = (attributes == null) ? 0 : attributes.length;

        for (int i = 0; i < n; i++) {

            CK_ATTRIBUTE attr = attributes[i];

            if (attr.type == CKA_TOKEN) {

                tokenObject = attr.getBoolean();

            } else if (attr.type == CKA_SENSITIVE) {

                sensitive = attr.getBoolean();

            } else if (attr.type == CKA_EXTRACTABLE) {

                extractable = attr.getBoolean();

            }

        }

        this.tokenObject = tokenObject;

        this.sensitive = sensitive;

        this.extractable = extractable;

        if (tokenObject == false) {

            session.addObject();

        }

    }

    // see JCA spec

    public final String getAlgorithm() {

        token.ensureValid();

        return algorithm;

    }

    // see JCA spec

    public final byte[] getEncoded() {

        byte[] b = getEncodedInternal();

        return (b == null) ? null : (byte[])b.clone();

    }

    abstract byte[] getEncodedInternal();

    public boolean equals(Object obj) {

        if (this == obj) {

            return true;

        }

        // equals() should never throw exceptions

        if (token.isValid() == false) {

            return false;

        }

        if (obj instanceof Key == false) {

            return false;

        }

        String thisFormat = getFormat();

        if (thisFormat == null) {

            // no encoding, key only equal to itself

            // XXX getEncoded() for unextractable keys will change that

            return false;

        }

        Key other = (Key)obj;

        if (thisFormat.equals(other.getFormat()) == false) {

            return false;

        }

        byte[] thisEnc = this.getEncodedInternal();

        byte[] otherEnc;

        if (obj instanceof P11Key) {

            otherEnc = ((P11Key)other).getEncodedInternal();

        } else {

            otherEnc = other.getEncoded();

        }

        return Arrays.equals(thisEnc, otherEnc);

    }

    public int hashCode() {

        // hashCode() should never throw exceptions

        if (token.isValid() == false) {

            return 0;

        }

        byte[] b1 = getEncodedInternal();

        if (b1 == null) {

            return 0;

        }

        int r = b1.length;

        for (int i = 0; i < b1.length; i++) {

            r += (b1[i] & 0xff) * 37;

        }

        return r;

    }

    protected Object writeReplace() throws ObjectStreamException {

        KeyRep.Type type;

        String format = getFormat();

        if (isPrivate() && "PKCS#8".equals(format)) {

            type = KeyRep.Type.PRIVATE;

        } else if (isPublic() && "X.509".equals(format)) {

            type = KeyRep.Type.PUBLIC;

        } else if (isSecret() && "RAW".equals(format)) {

            type = KeyRep.Type.SECRET;

        } else {

            // XXX short term serialization for unextractable keys

            throw new NotSerializableException

                ("Cannot serialize sensitive and unextractable keys");

        }

        return new KeyRep(type, getAlgorithm(), format, getEncoded());

    }

    public String toString() {

        token.ensureValid();

        String s1 = token.provider.getName() + " " + algorithm + " " + type

                + " key, " + keyLength + " bits";

        s1 += " (id " + keyID + ", "

                + (tokenObject ? "token" : "session") + " object";

        if (isPublic()) {

            s1 += ")";

        } else {

            s1 += ", " + (sensitive ? "" : "not ") + "sensitive";

            s1 += ", " + (extractable ? "" : "un") + "extractable)";

        }

        return s1;

    }

    int keyLength() {

        return keyLength;

    }

    boolean isPublic() {

        return type == PUBLIC;

    }

    boolean isPrivate() {

        return type == PRIVATE;

    }

    boolean isSecret() {

        return type == SECRET;

    }

    void fetchAttributes(CK_ATTRIBUTE[] attributes) {

        Session tempSession = null;

        try {

            tempSession = token.getOpSession();

            token.p11.C_GetAttributeValue(tempSession.id(), keyID, attributes);

        } catch (PKCS11Exception e) {

            throw new ProviderException(e);

        } finally {

            token.releaseSession(tempSession);

        }

    }

    protected void finalize() throws Throwable {

        if (tokenObject || (token.isValid() == false)) {

            super.finalize();

            return;

        }

        Session newSession = null;

        try {

            newSession = token.getOpSession();

            token.p11.C_DestroyObject(newSession.id(), keyID);

        } catch (PKCS11Exception e) {

            // ignore

        } finally {

            token.releaseSession(newSession);

            session.removeObject();

            super.finalize();

        }

    }

    private final static CK_ATTRIBUTE[] A0 = new CK_ATTRIBUTE[0];

    private static CK_ATTRIBUTE[] getAttributes(Session session, long keyID,

            CK_ATTRIBUTE[] knownAttributes, CK_ATTRIBUTE[] desiredAttributes) {

        if (knownAttributes == null) {

            knownAttributes = A0;

        }

        for (int i = 0; i < desiredAttributes.length; i++) {

            // For each desired attribute, check to see if we have the value

            // available already. If everything is here, we save a native call.

            CK_ATTRIBUTE attr = desiredAttributes[i];

            for (CK_ATTRIBUTE known : knownAttributes) {

                if ((attr.type == known.type) && (known.pValue != null)) {

                    attr.pValue = known.pValue;

                    break; // break inner for loop

                }

            }

            if (attr.pValue == null) {

                // nothing found, need to call C_GetAttributeValue()

                for (int j = 0; j < i; j++) {

                    // clear values copied from knownAttributes

                    desiredAttributes[j].pValue = null;

                }

                try {

                    session.token.p11.C_GetAttributeValue

                            (session.id(), keyID, desiredAttributes);

                } catch (PKCS11Exception e) {

                    throw new ProviderException(e);

                }

                break; // break loop, goto return

            }

        }

        return desiredAttributes;

    }

    static SecretKey secretKey(Session session, long keyID, String algorithm,

            int keyLength, CK_ATTRIBUTE[] attributes) {

        attributes = getAttributes(session, keyID, attributes, new CK_ATTRIBUTE[] {

            new CK_ATTRIBUTE(CKA_TOKEN),

            new CK_ATTRIBUTE(CKA_SENSITIVE),

            new CK_ATTRIBUTE(CKA_EXTRACTABLE),

        });

        return new P11SecretKey(session, keyID, algorithm, keyLength, attributes);

    }

    static SecretKey masterSecretKey(Session session, long keyID, String algorithm,

            int keyLength, CK_ATTRIBUTE[] attributes, int major, int minor) {

        attributes = getAttributes(session, keyID, attributes, new CK_ATTRIBUTE[] {

            new CK_ATTRIBUTE(CKA_TOKEN),

            new CK_ATTRIBUTE(CKA_SENSITIVE),

            new CK_ATTRIBUTE(CKA_EXTRACTABLE),

        });

        return new P11TlsMasterSecretKey

                (session, keyID, algorithm, keyLength, attributes, major, minor);

    }

    // we assume that all components of public keys are always accessible

    static PublicKey publicKey(Session session, long keyID, String algorithm,

            int keyLength, CK_ATTRIBUTE[] attributes) {

        if (algorithm.equals("RSA")) {

            return new P11RSAPublicKey

                (session, keyID, algorithm, keyLength, attributes);

        } else if (algorithm.equals("DSA")) {

            return new P11DSAPublicKey

                (session, keyID, algorithm, keyLength, attributes);

        } else if (algorithm.equals("DH")) {

            return new P11DHPublicKey

                (session, keyID, algorithm, keyLength, attributes);

        } else if (algorithm.equals("EC")) {

            return new P11ECPublicKey

                (session, keyID, algorithm, keyLength, attributes);

        } else {

            throw new ProviderException

                ("Unknown public key algorithm " + algorithm);

        }

    }

    static PrivateKey privateKey(Session session, long keyID, String algorithm,

            int keyLength, CK_ATTRIBUTE[] attributes) {

        attributes = getAttributes(session, keyID, attributes, new CK_ATTRIBUTE[] {

            new CK_ATTRIBUTE(CKA_TOKEN),

            new CK_ATTRIBUTE(CKA_SENSITIVE),

            new CK_ATTRIBUTE(CKA_EXTRACTABLE),

        });

        if (attributes[1].getBoolean() || (attributes[2].getBoolean() == false)) {

            return new P11PrivateKey

                (session, keyID, algorithm, keyLength, attributes);

        } else {

            if (algorithm.equals("RSA")) {

                // XXX better test for RSA CRT keys (single getAttributes() call)

                // we need to determine whether this is a CRT key

                // see if we can obtain the public exponent

                // this should also be readable for sensitive/extractable keys

                CK_ATTRIBUTE[] attrs2 = new CK_ATTRIBUTE[] {

                    new CK_ATTRIBUTE(CKA_PUBLIC_EXPONENT),

                };

                boolean crtKey;

                try {

                    session.token.p11.C_GetAttributeValue

                        (session.id(), keyID, attrs2);

                    crtKey = (attrs2[0].pValue instanceof byte[]);

                } catch (PKCS11Exception e) {

                    // ignore, assume not available

                    crtKey = false;

                }

                if (crtKey) {

                    return new P11RSAPrivateKey

                            (session, keyID, algorithm, keyLength, attributes);

                } else {

                    return new P11RSAPrivateNonCRTKey

                            (session, keyID, algorithm, keyLength, attributes);

                }

            } else if (algorithm.equals("DSA")) {

                return new P11DSAPrivateKey

                        (session, keyID, algorithm, keyLength, attributes);

            } else if (algorithm.equals("DH")) {

                return new P11DHPrivateKey

                        (session, keyID, algorithm, keyLength, attributes);

            } else if (algorithm.equals("EC")) {

                return new P11ECPrivateKey

                        (session, keyID, algorithm, keyLength, attributes);

            } else {

                throw new ProviderException

                        ("Unknown private key algorithm " + algorithm);

            }

        }

    }

    // class for sensitive and unextractable private keys

    private static final class P11PrivateKey extends P11Key

                                                implements PrivateKey {

        P11PrivateKey(Session session, long keyID, String algorithm,

                int keyLength, CK_ATTRIBUTE[] attributes) {

            super(PRIVATE, session, keyID, algorithm, keyLength, attributes);

        }

        // XXX temporary encoding for serialization purposes

        public String getFormat() {

            token.ensureValid();

            return null;

        }

        byte[] getEncodedInternal() {

            token.ensureValid();

            return null;

        }

    }

    private static class P11SecretKey extends P11Key implements SecretKey {

        private volatile byte[] encoded;

        P11SecretKey(Session session, long keyID, String algorithm,

                int keyLength, CK_ATTRIBUTE[] attributes) {

            super(SECRET, session, keyID, algorithm, keyLength, attributes);

        }

        public String getFormat() {

            token.ensureValid();

            if (sensitive || (extractable == false)) {

                return null;

            } else {

                return "RAW";

            }

        }

        byte[] getEncodedInternal() {

            token.ensureValid();

            if (getFormat() == null) {

                return null;

            }

            byte[] b = encoded;

            if (b == null) {

                synchronized (this) {

                    b = encoded;

                    if (b == null) {

                        Session tempSession = null;

                        try {

                            tempSession = token.getOpSession();

                            CK_ATTRIBUTE[] attributes = new CK_ATTRIBUTE[] {

                                new CK_ATTRIBUTE(CKA_VALUE),

                            };

                            token.p11.C_GetAttributeValue

                                (tempSession.id(), keyID, attributes);

                            b = attributes[0].getByteArray();

                        } catch (PKCS11Exception e) {

                            throw new ProviderException(e);

                        } finally {

                            token.releaseSession(tempSession);

                        }

                        encoded = b;

                    }

                }

            }

            return b;

        }

    }

    private static class P11TlsMasterSecretKey extends P11SecretKey

            implements TlsMasterSecret {

        private final int majorVersion, minorVersion;

        P11TlsMasterSecretKey(Session session, long keyID, String algorithm,

                int keyLength, CK_ATTRIBUTE[] attributes, int major, int minor) {

            super(session, keyID, algorithm, keyLength, attributes);

            this.majorVersion = major;

            this.minorVersion = minor;

        }

        public int getMajorVersion() {

            return majorVersion;

        }

        public int getMinorVersion() {

            return minorVersion;

        }

    }

    // RSA CRT private key

    private static final class P11RSAPrivateKey extends P11Key

                implements RSAPrivateCrtKey {

        private BigInteger n, e, d, p, q, pe, qe, coeff;

        private byte[] encoded;

        P11RSAPrivateKey(Session session, long keyID, String algorithm,

                int keyLength, CK_ATTRIBUTE[] attributes) {

            super(PRIVATE, session, keyID, algorithm, keyLength, attributes);

        }

        private synchronized void fetchValues() {

            token.ensureValid();

            if (n != null) {

                return;

            }

            CK_ATTRIBUTE[] attributes = new CK_ATTRIBUTE[] {

                new CK_ATTRIBUTE(CKA_MODULUS),

                new CK_ATTRIBUTE(CKA_PUBLIC_EXPONENT),

                new CK_ATTRIBUTE(CKA_PRIVATE_EXPONENT),

                new CK_ATTRIBUTE(CKA_PRIME_1),

                new CK_ATTRIBUTE(CKA_PRIME_2),

                new CK_ATTRIBUTE(CKA_EXPONENT_1),

                new CK_ATTRIBUTE(CKA_EXPONENT_2),

                new CK_ATTRIBUTE(CKA_COEFFICIENT),

            };

            fetchAttributes(attributes);

            n = attributes[0].getBigInteger();

            e = attributes[1].getBigInteger();

            d = attributes[2].getBigInteger();

            p = attributes[3].getBigInteger();

            q = attributes[4].getBigInteger();

            pe = attributes[5].getBigInteger();

            qe = attributes[6].getBigInteger();

            coeff = attributes[7].getBigInteger();

        }

        public String getFormat() {

            token.ensureValid();

            return "PKCS#8";

        }

        synchronized byte[] getEncodedInternal() {

            token.ensureValid();

            if (encoded == null) {

                fetchValues();

                try {

                    // XXX make constructor in SunRsaSign provider public

                    // and call it directly

                    KeyFactory factory = KeyFactory.getInstance

                        ("RSA", P11Util.getSunRsaSignProvider());

                    Key newKey = factory.translateKey(this);

                    encoded = newKey.getEncoded();

                } catch (GeneralSecurityException e) {

                    throw new ProviderException(e);

                }

            }

            return encoded;

        }

        public BigInteger getModulus() {

            fetchValues();

            return n;

        }

        public BigInteger getPublicExponent() {

            fetchValues();

            return e;

        }