/*

 * 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

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

 *

 * 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.

 *

 */

package sun.security.jgss.wrapper;

import java.util.HashMap;

import java.security.Provider;

import java.security.AccessController;

import java.security.PrivilegedAction;

import org.ietf.jgss.Oid;

import sun.security.action.PutAllAction;

/**

 * Defines the Sun NativeGSS provider for plugging in the

 * native GSS mechanisms to Java GSS.

 *

 * List of supported mechanisms depends on the local

 * machine configuration.

 *

 * @author Yu-Ching Valerie Peng

 */

public final class SunNativeProvider extends Provider {

    private static final long serialVersionUID = -238911724858694204L;

    private static final String NAME = "SunNativeGSS";

    private static final String INFO = "Sun Native GSS provider";

    private static final String MF_CLASS =

        "sun.security.jgss.wrapper.NativeGSSFactory";

    private static final String LIB_PROP = "sun.security.jgss.lib";

    private static final String DEBUG_PROP = "sun.security.nativegss.debug";

    private static HashMap MECH_MAP;

    static final Provider INSTANCE = new SunNativeProvider();

    static boolean DEBUG;

    static void debug(String message) {

        if (DEBUG) {

            if (message == null) {

                throw new NullPointerException();

            }

            System.out.println(NAME + ": " + message);

        }

    }

    static {

        MECH_MAP =

            AccessController.doPrivileged(new PrivilegedAction<HashMap>() {

                    public HashMap run() {

                        DEBUG = Boolean.parseBoolean

                            (System.getProperty(DEBUG_PROP));

                        try {

                            System.loadLibrary("j2gss");

                        } catch (Error err) {

                            debug("No j2gss library found!");

                            if (DEBUG) err.printStackTrace();

                            return null;

                        }

                        String gssLibs[] = new String[0];

                        String defaultLib = System.getProperty(LIB_PROP);

                        if (defaultLib == null || defaultLib.trim().equals("")) {

                            String osname = System.getProperty("os.name");

                            if (osname.startsWith("SunOS")) {

                                gssLibs = new String[]{ "libgss.so" };

                            } else if (osname.startsWith("Linux")) {

                                gssLibs = new String[]{

                                    "libgssapi.so",

                                    "libgssapi_krb5.so",

                                };

                            }

                        } else {

                            gssLibs = new String[]{ defaultLib };

                        }

                        for (String libName: gssLibs) {

                            if (GSSLibStub.init(libName)) {

                                debug("Loaded GSS library: " + libName);

                                Oid[] mechs = GSSLibStub.indicateMechs();

                                HashMap<String, String> map =

                                            new HashMap<String, String>();

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

                                    debug("Native MF for " + mechs[i]);

                                    map.put("GssApiMechanism." + mechs[i],

                                            MF_CLASS);

                                }

                                return map;

                            }

                        }

                        return null;

                    }

                });

    }

    public SunNativeProvider() {

        /* We are the Sun NativeGSS provider */

        super(NAME, 1.0, INFO);

        if (MECH_MAP != null) {

            AccessController.doPrivileged(new PutAllAction(this, MECH_MAP));

        }

    }

}