/*

 * Copyright (c) 2006, 2011, 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.ssl;

import java.io.IOException;

import javax.net.ssl.SSLProtocolException;

/*

 * For secure renegotiation, RFC5746 defines a new TLS extension,

 * "renegotiation_info" (with extension type 0xff01), which contains a

 * cryptographic binding to the enclosing TLS connection (if any) for

 * which the renegotiation is being performed.  The "extension data"

 * field of this extension contains a "RenegotiationInfo" structure:

 *

 *      struct {

 *          opaque renegotiated_connection<0..255>;

 *      } RenegotiationInfo;

 */

final class RenegotiationInfoExtension extends HelloExtension {

    private final byte[] renegotiated_connection;

    RenegotiationInfoExtension(byte[] clientVerifyData,

                byte[] serverVerifyData) {

        super(ExtensionType.EXT_RENEGOTIATION_INFO);

        if (clientVerifyData.length != 0) {

            renegotiated_connection =

                    new byte[clientVerifyData.length + serverVerifyData.length];

            System.arraycopy(clientVerifyData, 0, renegotiated_connection,

                    0, clientVerifyData.length);

            if (serverVerifyData.length != 0) {

                System.arraycopy(serverVerifyData, 0, renegotiated_connection,

                        clientVerifyData.length, serverVerifyData.length);

            }

        } else {

            // ignore both the client and server verify data.

            renegotiated_connection = new byte[0];

        }

    }

    RenegotiationInfoExtension(HandshakeInStream s, int len)

                throws IOException {

        super(ExtensionType.EXT_RENEGOTIATION_INFO);

        // check the extension length

        if (len < 1) {

            throw new SSLProtocolException("Invalid " + type + " extension");

        }

        int renegoInfoDataLen = s.getInt8();

        if (renegoInfoDataLen + 1 != len) {  // + 1 = the byte we just read

            throw new SSLProtocolException("Invalid " + type + " extension");

        }

        renegotiated_connection = new byte[renegoInfoDataLen];

        if (renegoInfoDataLen != 0) {

            s.read(renegotiated_connection, 0, renegoInfoDataLen);

        }

    }

    // Length of the encoded extension, including the type and length fields

    int length() {

        return 5 + renegotiated_connection.length;

    }

    void send(HandshakeOutStream s) throws IOException {

        s.putInt16(type.id);

        s.putInt16(renegotiated_connection.length + 1);

        s.putBytes8(renegotiated_connection);

    }

    boolean isEmpty() {

        return renegotiated_connection.length == 0;

    }

    byte[] getRenegotiatedConnection() {

        return renegotiated_connection;

    }

    public String toString() {

        return "Extension " + type + ", renegotiated_connection: " +

                    (renegotiated_connection.length == 0 ? "<empty>" :

                    Debug.toString(renegotiated_connection));

    }

}