status.java

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/*
 * Copyright (c) 2001 Sun Microsystems, Inc.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *       Sun Microsystems, Inc. for Project JXTA."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Sun", "Sun Microsystems, Inc.", "JXTA" and "Project JXTA" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written
 *    permission, please contact Project JXTA at http://www.jxta.org.
 *
 * 5. Products derived from this software may not be called "JXTA",
 *    nor may "JXTA" appear in their name, without prior written
 *    permission of Sun.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL SUN MICROSYSTEMS OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of Project JXTA.  For more
 * information on Project JXTA, please see
 * <http://www.jxta.org/>.
 *
 * This license is based on the BSD license adopted by the Apache Foundation.
 *
 * $Id: status.java,v 1.1 2006/03/20 01:03:39 bondolo Exp $
 */

package net.jxta.impl.shell.bin.pse;

import java.security.KeyStore;
import java.security.MessageDigest;
import java.security.cert.Certificate;
import java.security.cert.X509Certificate;
import java.util.Arrays;
import java.util.Enumeration;
import java.util.Iterator;

import java.io.IOException;
import java.security.KeyStoreException;

import net.jxta.credential.Credential;
import net.jxta.id.ID;
import net.jxta.membership.MembershipService;
import net.jxta.peergroup.PeerGroup;
import net.jxta.protocol.ModuleImplAdvertisement;

import net.jxta.impl.membership.pse.PSECredential;
import net.jxta.impl.membership.pse.PSEMembershipService;
import net.jxta.impl.membership.pse.PSEConfig;

import net.jxta.impl.shell.GetOpt;
import net.jxta.impl.shell.ShellApp;
import net.jxta.impl.shell.ShellEnv;

/**
 *  PSE.status
 **/
public class status extends ShellApp {
    
    /**
     *  {@inheritDoc}
     **/
    public int startApp(String[] argv ) {
        ShellEnv env = getEnv();
        PeerGroup current = (PeerGroup) env.get("stdgroup").getObject();
        
        GetOpt options = new GetOpt( argv, 0, "" );
        
        while( true ) {
            int option;
            try {
                option = options.getNextOption();
            } catch( IllegalArgumentException badopt ) {
                consoleMessage( "Illegal argument :" + badopt );
                return syntaxError();
            }
            
            if( -1 == option ) {
                break;
            }
            
            switch( option ) {
                
                default :
                    consoleMessage( "Unrecognized option" );
                    return syntaxError();
            }
        }
        
        if ( null != options.getNextParameter() ) {
            consoleMessage( "Unsupported parameter" );
            return syntaxError();
        }
        
        MembershipService membership = getGroup().getMembershipService();
        PSEMembershipService pseMembership = null;
        
        ModuleImplAdvertisement membershipImplAdv =
                (ModuleImplAdvertisement) membership.getImplAdvertisement();
        
        if( (null != membershipImplAdv) &&
                PSEMembershipService.pseMembershipSpecID.equals(membershipImplAdv.getModuleSpecID()) &&
                (membership instanceof PSEMembershipService) ) {
            pseMembership = (PSEMembershipService) membership;
        } else {
            if( null != membershipImplAdv ) {
                consoleMessage( "Group membership service is not PSE. (" + membershipImplAdv.getModuleSpecID() + "/" + membershipImplAdv.getDescription() + ")" );
            } else {
                consoleMessage( "Group membership service is not PSE. (" + membership.getClass().getName() + ")" );
            }
            
            return ShellApp.appNoError;
        }
        
        PSEConfig pseConfig = pseMembership.getPSEConfig();
        
        println( "Keystore initialized : " + pseConfig.isInitialized() );
        
        if( pseConfig.isInitialized() ) {
            if( null == pseMembership.getDefaultCredential() ) {
                println( "KeyStore has not been opened." );
                return ShellApp.appNoError;
            }
            
            KeyStore keyStore = pseConfig.getKeyStore();
            
            if( null != keyStore ) {
                println( "Keystore type : " + keyStore.getType() );
                println( "Keystore provider : " + keyStore.getProvider() );
            } else {
                consoleMessage( "Could not get keystore." );
            }
            
            Credential credential = pseMembership.getDefaultCredential();
            
            println( "Default credential : " + credential.getSubject() );
            
            Enumeration eachCredential = pseMembership.getCurrentCredentials();
            
            if( eachCredential.hasMoreElements() ) {
                println( "Credentials : " );
            }
            
            while( eachCredential.hasMoreElements() ) {
                Credential aCredential = (Credential) eachCredential.nextElement();
                
                println( "\tCredential : " + aCredential.getSubject().toString() );
            }

        }
            
        return ShellApp.appNoError;
    }
    
    /**
     * Gets the finger print of the certificate.
     */
    private String calcCertFingerPrint( Certificate cert ) throws Exception {
        byte[] derCert = cert.getEncoded();
        MessageDigest md = MessageDigest.getInstance( "SHA1" );
        byte[] digest = md.digest(derCert);
        StringBuffer hexes = new StringBuffer( );
        for( int eachByte = 0; eachByte < digest.length; eachByte++ ) {
            hexes.append( toHexDigits(digest[eachByte]) );
            if( eachByte + 1 != digest.length ) {
                hexes.append( ':' );
            }
        }
        
        return hexes.toString();
    }
    
    /**
     *  Private replacement for toHexString since we need the leading 0 digits.
     *  Returns a String containing byte value encoded as 2 hex characters.
     *
     *  @param  theByte a byte containing the value to be encoded.
     *  @return	String containing byte value encoded as 2 hex characters.
     **/
    private static String toHexDigits( byte theByte ) {
        final char [] HEXDIGITS = { '0', '1', '2', '3', '4', '5', '6', '7',
        '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
        StringBuffer result = new StringBuffer(2);
        
        result.append( HEXDIGITS[(theByte >>> 4) & 15] );
        result.append( HEXDIGITS[theByte & 15] );
        
        return result.toString();
    }
    
    private int syntaxError() {
        consoleMessage( "Usage: pse.status " );
        return ShellApp.appParamError;
    }
    
    /**
     *  {@inheritDoc}
     **/
    public String getDescription() {
        return "Display status infomation for the group's PSE Membership";
    }
    
    /**
     *  {@inheritDoc}
     **/
    public void help() {
        println("NAME");
        println("     pse.status  - " + getDescription() );
        println(" ");
        println("SYNOPSIS");
        println(" ");
        println("     pse.status ");
        println(" ");
        println("OPTIONS");
        println(" ");
        println(" ");
        println("DESCRIPTION");
        println(" ");
        println("     Prints status information for the current peer group's PSE ");
        println("     membership service. ");
        println(" ");
        println("EXAMPLE");
        println(" ");
        println("    JXTA> pse.status");
        println(" ");
        println(" ");
        println("SEE ALSO");
        println("     pse.certs pse.keys");
    }
}