/*

 * Copyright 1997-2006 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.pkcs;

import java.io.IOException;

import java.io.OutputStream;

import java.util.Hashtable;

import sun.security.util.DerEncoder;

import sun.security.util.DerValue;

import sun.security.util.DerInputStream;

import sun.security.util.DerOutputStream;

import sun.security.util.ObjectIdentifier;

/**

 * A set of attributes of class PKCS9Attribute.

 *

 * @author Douglas Hoover

 */

public class PKCS9Attributes {

    /**

     * Attributes in this set indexed by OID.

     */

    private final Hashtable<ObjectIdentifier, PKCS9Attribute> attributes =

        new Hashtable<ObjectIdentifier, PKCS9Attribute>(3);

    /**

     * The keys of this hashtable are the OIDs of permitted attributes.

     */

    private final Hashtable<ObjectIdentifier, ObjectIdentifier> permittedAttributes;

    /**

     * The DER encoding of this attribute set.  The tag byte must be

     * DerValue.tag_SetOf.

     */

    private final byte[] derEncoding;

    /*

     * Contols how attributes, which are not recognized by the PKCS9Attribute

     * class, are handled during parsing.

     */

    private boolean ignoreUnsupportedAttributes = false;

    /**

     * Construct a set of PKCS9 Attributes from its

     * DER encoding on a DerInputStream, accepting only attributes

     * with OIDs on the given

     * list.  If the array is null, accept all attributes supported by

     * class PKCS9Attribute.

     *

     * @param permittedAttributes

     * Array of attribute OIDs that will be accepted.

     * @param in

     * the contents of the DER encoding of the attribute set.

     *

     * @exception IOException

     * on i/o error, encoding syntax error, unacceptable or

     * unsupported attribute, or duplicate attribute.

     *

     * @see PKCS9Attribute

     */

    public PKCS9Attributes(ObjectIdentifier[] permittedAttributes,

                           DerInputStream in) throws IOException {

        if (permittedAttributes != null) {

            this.permittedAttributes =

                new Hashtable<ObjectIdentifier, ObjectIdentifier>(

                                                permittedAttributes.length);

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

                this.permittedAttributes.put(permittedAttributes[i],

                                             permittedAttributes[i]);

        } else {

            this.permittedAttributes = null;

        }

        // derEncoding initialized in <code>decode()</code>

        derEncoding = decode(in);

    }

    /**

     * Construct a set of PKCS9 Attributes from the contents of its

     * DER encoding on a DerInputStream.  Accept all attributes

     * supported by class PKCS9Attribute and reject any unsupported

     * attributes.

     *

     * @param in the contents of the DER encoding of the attribute set.

     * @exception IOException

     * on i/o error, encoding syntax error, or unsupported or

     * duplicate attribute.

     *

     * @see PKCS9Attribute

     */

    public PKCS9Attributes(DerInputStream in) throws IOException {

        this(in, false);

    }

    /**

     * Construct a set of PKCS9 Attributes from the contents of its

     * DER encoding on a DerInputStream.  Accept all attributes

     * supported by class PKCS9Attribute and ignore any unsupported

     * attributes, if directed.

     *

     * @param in the contents of the DER encoding of the attribute set.

     * @param ignoreUnsupportedAttributes If true then any attributes

     * not supported by the PKCS9Attribute class are ignored. Otherwise

     * unsupported attributes cause an exception to be thrown.

     * @exception IOException

     * on i/o error, encoding syntax error, or unsupported or

     * duplicate attribute.

     *

     * @see PKCS9Attribute

     */

    public PKCS9Attributes(DerInputStream in,

        boolean ignoreUnsupportedAttributes) throws IOException {

        this.ignoreUnsupportedAttributes = ignoreUnsupportedAttributes;

        // derEncoding initialized in <code>decode()</code>

        derEncoding = decode(in);

        permittedAttributes = null;

    }

    /**

     * Construct a set of PKCS9 Attributes from the given array of

     * PKCS9 attributes.

     * DER encoding on a DerInputStream.  All attributes in

     * <code>attribs</code> must be

     * supported by class PKCS9Attribute.

     *

     * @exception IOException

     * on i/o error, encoding syntax error, or unsupported or

     * duplicate attribute.

     *

     * @see PKCS9Attribute

     */

    public PKCS9Attributes(PKCS9Attribute[] attribs)

    throws IllegalArgumentException, IOException {

        ObjectIdentifier oid;

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

            oid = attribs[i].getOID();

            if (attributes.containsKey(oid))

                throw new IllegalArgumentException(

                          "PKCSAttribute " + attribs[i].getOID() +

                          " duplicated while constructing " +

                          "PKCS9Attributes.");

            attributes.put(oid, attribs[i]);

        }

        derEncoding = generateDerEncoding();

        permittedAttributes = null;

    }

    /**

     * Decode this set of PKCS9 attributes from the contents of its

     * DER encoding. Ignores unsupported attributes when directed.

     *

     * @param in

     * the contents of the DER encoding of the attribute set.

     *

     * @exception IOException

     * on i/o error, encoding syntax error, unacceptable or

     * unsupported attribute, or duplicate attribute.

     */

    private byte[] decode(DerInputStream in) throws IOException {

        DerValue val = in.getDerValue();

        // save the DER encoding with its proper tag byte.

        byte[] derEncoding = val.toByteArray();

        derEncoding[0] = DerValue.tag_SetOf;

        DerInputStream derIn = new DerInputStream(derEncoding);

        DerValue[] derVals = derIn.getSet(3,true);

        PKCS9Attribute attrib;

        ObjectIdentifier oid;

        boolean reuseEncoding = true;

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

            try {

                attrib = new PKCS9Attribute(derVals[i]);

            } catch (ParsingException e) {

                if (ignoreUnsupportedAttributes) {

                    reuseEncoding = false; // cannot reuse supplied DER encoding

                    continue; // skip

                } else {

                    throw e;

                }

            }

            oid = attrib.getOID();

            if (attributes.get(oid) != null)

                throw new IOException("Duplicate PKCS9 attribute: " + oid);

            if (permittedAttributes != null &&

                !permittedAttributes.containsKey(oid))

                throw new IOException("Attribute " + oid +

                                      " not permitted in this attribute set");

            attributes.put(oid, attrib);

        }

        return reuseEncoding ? derEncoding : generateDerEncoding();

    }

    /**

     * Put the DER encoding of this PKCS9 attribute set on an

     * DerOutputStream, tagged with the given implicit tag.

     *

     * @param tag the implicit tag to use in the DER encoding.

     * @param out the output stream on which to put the DER encoding.

     *

     * @exception IOException  on output error.

     */

    public void encode(byte tag, OutputStream out) throws IOException {

        out.write(tag);

        out.write(derEncoding, 1, derEncoding.length -1);

    }

    private byte[] generateDerEncoding() throws IOException {

        DerOutputStream out = new DerOutputStream();

        Object[] attribVals = attributes.values().toArray();

        out.putOrderedSetOf(DerValue.tag_SetOf,

                            castToDerEncoder(attribVals));

        return out.toByteArray();

    }

    /**

     * Return the DER encoding of this attribute set, tagged with

     * DerValue.tag_SetOf.

     */

    public byte[] getDerEncoding() throws IOException {

        return derEncoding.clone();

    }

    /**

     * Get an attribute from this set.

     */

    public PKCS9Attribute getAttribute(ObjectIdentifier oid) {

        return attributes.get(oid);

    }

    /**

     * Get an attribute from this set.

     */

    public PKCS9Attribute getAttribute(String name) {

        return attributes.get(PKCS9Attribute.getOID(name));

    }

    /**

     * Get an array of all attributes in this set, in order of OID.

     */

    public PKCS9Attribute[] getAttributes() {

        PKCS9Attribute[] attribs = new PKCS9Attribute[attributes.size()];

        ObjectIdentifier oid;

        int j = 0;

        for (int i=1; i < PKCS9Attribute.PKCS9_OIDS.length &&

                      j < attribs.length; i++) {

            attribs[j] = getAttribute(PKCS9Attribute.PKCS9_OIDS[i]);

            if (attribs[j] != null)

                j++;

        }

        return attribs;

    }

    /**

     * Get an attribute value by OID.

     */

    public Object getAttributeValue(ObjectIdentifier oid)

    throws IOException {

        try {

            Object value = getAttribute(oid).getValue();

            return value;

        } catch (NullPointerException ex) {

            throw new IOException("No value found for attribute " + oid);

        }

    }

    /**

     *  Get an attribute value by type name.

     */

    public Object getAttributeValue(String name) throws IOException {

        ObjectIdentifier oid = PKCS9Attribute.getOID(name);

        if (oid == null)

            throw new IOException("Attribute name " + name +

                                  " not recognized or not supported.");

        return getAttributeValue(oid);

    }

    /**

     * Returns the PKCS9 block in a printable string form.

     */

    public String toString() {

        StringBuffer buf = new StringBuffer(200);

        buf.append("PKCS9 Attributes: [\n\t");

        ObjectIdentifier oid;

        PKCS9Attribute value;

        boolean first = true;

        for (int i = 1; i < PKCS9Attribute.PKCS9_OIDS.length; i++) {

            value = getAttribute(PKCS9Attribute.PKCS9_OIDS[i]);

            if (value == null) continue;

            // we have a value; print it

            if (first)

                first = false;

            else

                buf.append(";\n\t");

            buf.append(value.toString());

        }

        buf.append("\n\t] (end PKCS9 Attributes)");

        return buf.toString();

    }

    /**

     * Cast an object array whose components are

     * <code>DerEncoder</code>s to <code>DerEncoder[]</code>.

     */

    static DerEncoder[] castToDerEncoder(Object[] objs) {

        DerEncoder[] encoders = new DerEncoder[objs.length];

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

            encoders[i] = (DerEncoder) objs[i];

        return encoders;

    }

}