/*
 * 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
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/*
 *
 *  (C) Copyright IBM Corp. 1999 All Rights Reserved.
 *  Copyright 1997 The Open Group Research Institute.  All rights reserved.
 */

package sun.security.krb5.internal.ccache;

import sun.security.krb5.*;
import sun.security.krb5.internal.*;

import java.util.List;
import java.io.IOException;

/**
 * CredentialsCache stores credentials(tickets, session keys, etc) in a semi-permanent store
 * for later use by different program.
 *
 * @author Yanni Zhang
 */
public abstract class CredentialsCache {
    static CredentialsCache singleton = null;
    static String cacheName;
    private static boolean DEBUG = Krb5.DEBUG;

    public static CredentialsCache getInstance(PrincipalName principal) {
        return FileCredentialsCache.acquireInstance(principal, null);
    }

    public static CredentialsCache getInstance(String cache) {
        if ((cache.length() >= 5) && cache.substring(0, 5).equalsIgnoreCase("FILE:")) {
            return FileCredentialsCache.acquireInstance(null, cache.substring(5));
        }
        // XXX else, memory credential cache
        // default is file credential cache.
        return FileCredentialsCache.acquireInstance(null, cache);
    }

    public static CredentialsCache getInstance(PrincipalName principal,
                                               String cache) {

        // XXX Modify this to use URL framework of the JDK
        if (cache != null &&
            (cache.length() >= 5) &&
            cache.regionMatches(true, 0, "FILE:", 0, 5)) {
            return FileCredentialsCache.acquireInstance(principal,
                                                        cache.substring(5));
        }

        // When cache is null, read the default cache.
        // XXX else ..we haven't provided support for memory credential cache
        // yet. (supported in native code)
        // default is file credentials cache.
        return FileCredentialsCache.acquireInstance(principal, cache);

    }

    /**
     * Gets the default credentials cache.
     */
    public static CredentialsCache getInstance() {
        // Default credentials cache is file-based.
        return FileCredentialsCache.acquireInstance();
    }

    public static CredentialsCache create(PrincipalName principal, String name) {
        if (name == null) {
            throw new RuntimeException("cache name error");
        }
        if ((name.length() >= 5)
            && name.regionMatches(true, 0, "FILE:", 0, 5)) {
            name = name.substring(5);
            return (FileCredentialsCache.New(principal, name));
        }
        // else return file credentials cache
        // default is file credentials cache.
        return (FileCredentialsCache.New(principal, name));
    }

    public static CredentialsCache create(PrincipalName principal) {
        // create a default credentials cache for a specified principal
        return (FileCredentialsCache.New(principal));
    }

    public static String cacheName() {
        return cacheName;
    }

    public abstract PrincipalName getPrimaryPrincipal();
    public abstract void update(Credentials c);
    public abstract void save() throws IOException, KrbException;
    public abstract Credentials[] getCredsList();
    public abstract Credentials getDefaultCreds();
    public abstract sun.security.krb5.Credentials getInitialCreds();
    public abstract Credentials getCreds(PrincipalName sname);
    public abstract Credentials getCreds(LoginOptions options, PrincipalName sname);
    public abstract void addConfigEntry(ConfigEntry e);
    public abstract List<ConfigEntry> getConfigEntries();

    public ConfigEntry getConfigEntry(String name) {
        List<ConfigEntry> entries = getConfigEntries();
        if (entries != null) {
            for (ConfigEntry e : entries) {
                if (e.getName().equals(name)) {
                    return e;
                }
            }
        }
        return null;
    }

    public static class ConfigEntry {

        public ConfigEntry(String name, PrincipalName princ, byte[] data) {
            this.name = name;
            this.princ = princ;
            this.data = data;
        }

        private final String name;
        private final PrincipalName princ;
        private final byte[] data; // not worth cloning

        public String getName() {
            return name;
        }

        public PrincipalName getPrinc() {
            return princ;
        }

        public byte[] getData() {
            return data;
        }

        @Override
        public String toString() {
            return name + (princ != null ? ("." + princ) : "")
                    + ": " + new String(data);
        }

        public PrincipalName getSName() {
            try {
                return new PrincipalName("krb5_ccache_conf_data/" + name
                        + (princ != null ? ("/" + princ) : "")
                        + "@X-CACHECONF:");
            } catch (RealmException e) {
                throw new AssertionError(e);
            }
        }
    }
}