unixauthenticator.java

java 开发的一个电子邮局,挺实用的

/* $Id: UnixAuthenticator.java,v 1.3 2000/12/30 10:39:09 wastl Exp $ */
import net.wastl.webmail.server.*;
import net.wastl.webmail.exceptions.*;
import java.io.*;
import java.util.*;

import net.wastl.webmail.misc.*;
import net.wastl.webmail.config.ConfigScheme;

/**
 * UnixAuthenticator.java
 *
 *
 * Created: Mon Apr 19 13:43:48 1999
 *
 * @author Sebastian Schaffert
 * @version
 */

public class UnixAuthenticator extends Authenticator {
    
    public final String VERSION="1.2";

    public static final String passwd="/etc/passwd";
    public static final String shadow="/etc/shadow";

    public UnixAuthenticator() {
	super();
    }

    public String getVersion() {
	return VERSION;
    }

    public void init(Storage store) {
    }

    public void register(ConfigScheme store) {
	key="UNIX";
	store.configAddChoice("AUTH",key,"Authenticate against the local Unix server's passwd/shadow files. Password change not possible.");
    }	

    public void authenticatePreUserData(String user, String domain,
     String given_passwd) throws InvalidPasswordException 
    {
	super.authenticatePreUserData(user,domain,given_passwd);
	String login=user;
	try {
	    File f_passwd=new File(passwd);
	    File f_shadow=new File(shadow);
	    BufferedReader in;
	    if(f_shadow.exists()) {		
		in=new BufferedReader(new InputStreamReader(new FileInputStream(f_shadow)));
	    } else {
		in=new BufferedReader(new InputStreamReader(new FileInputStream(f_passwd)));
	    }
	    String line;
	    line=in.readLine();
	    while(line != null) {
		if(line.startsWith(login)) break;
		line=in.readLine();
	    }
	    
	    if(line == null) throw new InvalidPasswordException("Invalid user: "+login);
	    
	    
	    StringTokenizer tok=new StringTokenizer(line,":");
	    String my_login=tok.nextToken();
	    String password=tok.nextToken();

	    if(!password.equals(Helper.crypt(password,given_passwd))) {
		WebMailServer.getStorage().log(Storage.LOG_WARN,"UnixAuthentication: user "+login+
					       " authentication failed.");
		throw new InvalidPasswordException("Unix authentication failed");
	    }		
	    WebMailServer.getStorage().log(Storage.LOG_INFO,"UnixAuthentication: user "+login+
					   " authenticated successfully.");
	} catch(IOException ex) {
	    System.err.println("*** Cannot use UnixAuthentication and shadow passwords if WebMail is not executed as user 'root'! ***");
	    throw new InvalidPasswordException("User login denied due to configuration error (contact system administrator)");
	}
    }

    /**
     * Don't allow to change Unix-Passwords as this could mess things up.
     */
    public boolean canChangePassword() {
	return false;
    }    
} // UnixAuthenticator