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 * Copyright (c) 2003, 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
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package sun.security.pkcs11;

import java.util.*;
import java.util.concurrent.*;

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

TemplateManager class.
Not all PKCS#11 tokens are created equal. One token may require that one
value is specified when creating a certain type of object. Another token
may require a different value. Yet another token may only work if the
attribute is not specified at all.
In order to allow an application to work unmodified with all those
different tokens, the SunPKCS11 provider makes the attributes that are
specified and their value configurable. Hence, only the SunPKCS11
configuration file has to be tweaked at deployment time to allow all
existing applications to be used.
The template manager is responsible for reading the attribute configuration
information and to make it available to the various internal components
of the SunPKCS11 provider.
Author:
 Andreas Sterbenz
Since:
  1.5/**
 * TemplateManager class.
 *
 * Not all PKCS#11 tokens are created equal. One token may require that one
 * value is specified when creating a certain type of object. Another token
 * may require a different value. Yet another token may only work if the
 * attribute is not specified at all.
 *
 * In order to allow an application to work unmodified with all those
 * different tokens, the SunPKCS11 provider makes the attributes that are
 * specified and their value configurable. Hence, only the SunPKCS11
 * configuration file has to be tweaked at deployment time to allow all
 * existing applications to be used.
 *
 * The template manager is responsible for reading the attribute configuration
 * information and to make it available to the various internal components
 * of the SunPKCS11 provider.
 *
 * @author  Andreas Sterbenz
 * @since   1.5
 */
final class TemplateManager {

    private final static boolean DEBUG = false;

    // constant for any operation (either O_IMPORT or O_GENERATE)
    final static String O_ANY      = "*";
    // constant for operation create ("importing" existing key material)
    final static String O_IMPORT   = "import";
    // constant for operation generate (generating new key material)
    final static String O_GENERATE = "generate";

    private static class KeyAndTemplate {
        final TemplateKey key;
        final Template template;

        KeyAndTemplate(TemplateKey key, Template template) {
            this.key = key;
            this.template = template;
        }
    }

    // primitive templates contains the individual template configuration
    // entries from the configuration file
    private final List<KeyAndTemplate> primitiveTemplates;

    // composite templates is a cache of the exact configuration template for
    // each specific TemplateKey (no wildcards). the entries are created
    // on demand during first use by compositing all applicable
    // primitive template entries. the result is then stored in this map
    // for performance
    private final Map<TemplateKey,Template> compositeTemplates;

    TemplateManager() {
        primitiveTemplates = new ArrayList<KeyAndTemplate>();
        compositeTemplates = new ConcurrentHashMap<TemplateKey,Template>();
    }

    // add a template. Called by Config.
    void addTemplate(String op, long objectClass, long keyAlgorithm,
            CK_ATTRIBUTE[] attrs) {
        TemplateKey key = new TemplateKey(op, objectClass, keyAlgorithm);
        Template template = new Template(attrs);
        if (DEBUG) {
            System.out.println("Adding " + key + " -> " + template);
        }
        primitiveTemplates.add(new KeyAndTemplate(key, template));
    }

    private Template getTemplate(TemplateKey key) {
        Template template = compositeTemplates.get(key);
        if (template == null) {
            template = buildCompositeTemplate(key);
            compositeTemplates.put(key, template);
        }
        return template;
    }

    // Get the attributes for the requested op and combine them with attrs.
    // This is the method called by the implementation to obtain the
    // attributes.
    CK_ATTRIBUTE[] getAttributes(String op, long type, long alg,
            CK_ATTRIBUTE[] attrs) {
        TemplateKey key = new TemplateKey(op, type, alg);
        Template template = getTemplate(key);
        CK_ATTRIBUTE[] newAttrs = template.getAttributes(attrs);
        if (DEBUG) {
            System.out.println(key + " -> " + Arrays.asList(newAttrs));
        }
        return newAttrs;
    }

    // build a composite template for the given key
    private Template buildCompositeTemplate(TemplateKey key) {
        Template comp = new Template();
        // iterate through primitive templates and add all that apply
        for (KeyAndTemplate entry : primitiveTemplates) {
            if (entry.key.appliesTo(key)) {
                comp.add(entry.template);
            }
        }
        return comp;
    }

    
Nested class representing a template identifier.
/**
     * Nested class representing a template identifier.
     */
    private static final class TemplateKey {
        final String operation;
        final long keyType;
        final long keyAlgorithm;
        TemplateKey(String operation, long keyType, long keyAlgorithm) {
            this.operation = operation;
            this.keyType = keyType;
            this.keyAlgorithm = keyAlgorithm;
        }
        public boolean equals(Object obj) {
            if (this == obj) {
                return true;
            }
            if (obj instanceof TemplateKey == false) {
                return false;
            }
            TemplateKey other = (TemplateKey)obj;
            boolean match = this.operation.equals(other.operation)
                        && (this.keyType == other.keyType)
                        && (this.keyAlgorithm == other.keyAlgorithm);
            return match;
        }
        public int hashCode() {
            return operation.hashCode() + (int)keyType + (int)keyAlgorithm;
        }
        boolean appliesTo(TemplateKey key) {
            if (operation.equals(O_ANY) || operation.equals(key.operation)) {
                if ((keyType == PCKO_ANY) || (keyType == key.keyType)) {
                    if ((keyAlgorithm == PCKK_ANY)
                                || (keyAlgorithm == key.keyAlgorithm)) {
                        return true;
                    }
                }
            }
            return false;
        }
        public String toString() {
            return "(" + operation + ","
                + Functions.getObjectClassName(keyType)
                + "," + Functions.getKeyName(keyAlgorithm) + ")";
        }
    }

    
Nested class representing template attributes.
/**
     * Nested class representing template attributes.
     */
    private static final class Template {

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

        private CK_ATTRIBUTE[] attributes;

        Template() {
            attributes = A0;
        }

        Template(CK_ATTRIBUTE[] attributes) {
            this.attributes = attributes;
        }

        void add(Template template) {
            attributes = getAttributes(template.attributes);
        }

        CK_ATTRIBUTE[] getAttributes(CK_ATTRIBUTE[] attrs) {
            return combine(attributes, attrs);
        }

        
Combine two sets of attributes. The second set has precedence
over the first and overrides its settings.
/**
         * Combine two sets of attributes. The second set has precedence
         * over the first and overrides its settings.
         */
        private static CK_ATTRIBUTE[] combine(CK_ATTRIBUTE[] attrs1,
                CK_ATTRIBUTE[] attrs2) {
            List<CK_ATTRIBUTE> attrs = new ArrayList<CK_ATTRIBUTE>();
            for (CK_ATTRIBUTE attr : attrs1) {
                if (attr.pValue != null) {
                    attrs.add(attr);
                }
            }
            for (CK_ATTRIBUTE attr2 : attrs2) {
                long type = attr2.type;
                for (CK_ATTRIBUTE attr1 : attrs1) {
                    if (attr1.type == type) {
                        attrs.remove(attr1);
                    }
                }
                if (attr2.pValue != null) {
                    attrs.add(attr2);
                }
            }
            return attrs.toArray(A0);
        }

        public String toString() {
            return Arrays.asList(attributes).toString();
        }

    }

}