Jetty example source code file (DigestAuthenticator.java)

This example Jetty source code file (DigestAuthenticator.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Jetty tags/keywords

credential, digest, digest, http, io, ioexception, md5, messagedigest, messagedigest, principal, quotedstringtokenizer, request, request, response, response, security, servlet, string, string

The Jetty DigestAuthenticator.java source code

// ========================================================================
// Copyright 2002-2005 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at 
// http://www.apache.org/licenses/LICENSE-2.0
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ========================================================================

package org.mortbay.jetty.security;

import java.io.IOException;
import java.security.MessageDigest;
import java.security.Principal;

import javax.servlet.http.HttpServletResponse;

import org.mortbay.jetty.HttpHeaders;
import org.mortbay.jetty.Request;
import org.mortbay.jetty.Response;
import org.mortbay.log.Log;
import org.mortbay.util.QuotedStringTokenizer;
import org.mortbay.util.StringUtil;
import org.mortbay.util.TypeUtil;

/* ------------------------------------------------------------ */
/** DIGEST authentication.
 *
 * @author Greg Wilkins (gregw)
 */
public class DigestAuthenticator implements Authenticator
{
    protected long maxNonceAge=0;
    protected long nonceSecret=this.hashCode() ^ System.currentTimeMillis();
    protected boolean useStale=false;
    
    
    /* ------------------------------------------------------------ */
    /** 
     * @return UserPrinciple if authenticated or null if not. If
     * Authentication fails, then the authenticator may have committed
     * the response as an auth challenge or redirect.
     * @exception IOException 
     */
    public Principal authenticate(UserRealm realm,
                                           String pathInContext,
                                           Request request,
                                           Response response)
        throws IOException
    {
        // Get the user if we can
        boolean stale=false;
        Principal user=null;
        String credentials = request.getHeader(HttpHeaders.AUTHORIZATION);
        
        if (credentials!=null )
        {
            if(Log.isDebugEnabled())Log.debug("Credentials: "+credentials);
            QuotedStringTokenizer tokenizer = new QuotedStringTokenizer(credentials,
                                                                        "=, ",
                                                                        true,
                                                                        false);
            Digest digest=new Digest(request.getMethod());
            String last=null;
            String name=null;

          loop:
            while (tokenizer.hasMoreTokens())
            {
                String tok = tokenizer.nextToken();
                char c=(tok.length()==1)?tok.charAt(0):'\0';

                switch (c)
                {
                  case '=':
                      name=last;
                      last=tok;
                      break;
                  case ',':
                      name=null;
                  case ' ':
                      break;

                  default:
                      last=tok;
                      if (name!=null)
                      {
                          if ("username".equalsIgnoreCase(name))
                              digest.username=tok;
                          else if ("realm".equalsIgnoreCase(name))
                              digest.realm=tok;
                          else if ("nonce".equalsIgnoreCase(name))
                              digest.nonce=tok;
                          else if ("nc".equalsIgnoreCase(name))
                              digest.nc=tok;
                          else if ("cnonce".equalsIgnoreCase(name))
                              digest.cnonce=tok;
                          else if ("qop".equalsIgnoreCase(name))
                              digest.qop=tok;
                          else if ("uri".equalsIgnoreCase(name))
                              digest.uri=tok;
                          else if ("response".equalsIgnoreCase(name))
                              digest.response=tok;
                          break;
                      }
                }
            }            

            int n=checkNonce(digest.nonce,request);
            if (n>0)
                user = realm.authenticate(digest.username,digest,request);
            else if (n==0)
                stale = true;
            
            if (user==null)
                Log.warn("AUTH FAILURE: user "+StringUtil.printable(digest.username));
            else    
            {
                request.setAuthType(Constraint.__DIGEST_AUTH);
                request.setUserPrincipal(user);                
            }
        }

        // Challenge if we have no user
        if (user==null && response!=null)
            sendChallenge(realm,request,response,stale);
        
        return user;
    }
    
    /* ------------------------------------------------------------ */
    public String getAuthMethod()
    {
        return Constraint.__DIGEST_AUTH;
    }
    
    /* ------------------------------------------------------------ */
    public void sendChallenge(UserRealm realm,
                              Request request,
                              Response response,
                              boolean stale)
        throws IOException
    {
        String contextPath=request.getContextPath();
        response.setHeader(HttpHeaders.WWW_AUTHENTICATE,
			    "Digest realm=\""+realm.getName()+
			    "\", domain=\""+contextPath +
			    "\", nonce=\""+newNonce(request)+
			    "\", algorithm=MD5, qop=\"auth\"" + (useStale?(" stale="+stale):"")
                          );
        
        response.sendError(HttpServletResponse.SC_UNAUTHORIZED);
    }

    /* ------------------------------------------------------------ */
    public String newNonce(Request request)
    {
        long ts=request.getTimeStamp();
        long sk=nonceSecret;
        
        byte[] nounce = new byte[24];
        for (int i=0;i<8;i++)
        {
            nounce[i]=(byte)(ts&0xff);
            ts=ts>>8;
            nounce[8+i]=(byte)(sk&0xff);
            sk=sk>>8;
        }
        
        byte[] hash=null;
        try
        {
            MessageDigest md = MessageDigest.getInstance("MD5");
            md.reset();
            md.update(nounce,0,16);
            hash = md.digest();
        }
        catch(Exception e)
        {
            Log.warn(e);
        }
        
        for (int i=0;i<hash.length;i++)
        {
            nounce[8+i]=hash[i];
            if (i==23)
                break;
        }
        
        return new String(B64Code.encode(nounce));
    }

    /**
     * @param nonce
     * @param request
     * @return -1 for a bad nonce, 0 for a stale none, 1 for a good nonce
     */
    /* ------------------------------------------------------------ */
    public int checkNonce(String nonce, Request request)
    {
        try
        {
            byte[] n = B64Code.decode(nonce.toCharArray());
            if (n.length!=24)
                return -1;
            
            long ts=0;
            long sk=nonceSecret;
            byte[] n2 = new byte[16];
            System.arraycopy(n, 0, n2, 0, 8);
            for (int i=0;i<8;i++)
            {
                n2[8+i]=(byte)(sk&0xff);
                sk=sk>>8;
                ts=(ts<<8)+(0xff&(long)n[7-i]);
            }
            
            long age=request.getTimeStamp()-ts;
            if (Log.isDebugEnabled()) Log.debug("age="+age);
            
            byte[] hash=null;
            try
            {
                MessageDigest md = MessageDigest.getInstance("MD5");
                md.reset();
                md.update(n2,0,16);
                hash = md.digest();
            }
            catch(Exception e)
            {
                Log.warn(e);
            }
            
            for (int i=0;i<16;i++)
                if (n[i+8]!=hash[i])
                    return -1;
                
            if(maxNonceAge>0 && (age<0 || age>maxNonceAge))
                return 0; // stale
            
            return 1;
        }
        catch(Exception e)
        {
            Log.ignore(e);
        }
        return -1;
    }

    /* ------------------------------------------------------------ */
    /* ------------------------------------------------------------ */
    /* ------------------------------------------------------------ */
    private static class Digest extends Credential
    {
        String method=null;
        String username = null;
        String realm = null;
        String nonce = null;
        String nc = null;
        String cnonce = null;
        String qop = null;
        String uri = null;
        String response=null;
        
        /* ------------------------------------------------------------ */
        Digest(String m)
        {
            method=m;
        }
        
        /* ------------------------------------------------------------ */
        public boolean check(Object credentials)
        {
            String password=(credentials instanceof String)
                ?(String)credentials
                :credentials.toString();
            
            try{
                MessageDigest md = MessageDigest.getInstance("MD5");
                byte[] ha1;
                if(credentials instanceof Credential.MD5)
                {
                    // Credentials are already a MD5 digest - assume it's in
                    // form user:realm:password (we have no way to know since 
                    // it's a digest, alright?)
                    ha1 = ((Credential.MD5)credentials).getDigest();
                }
                else
                {
                    // calc A1 digest
                    md.update(username.getBytes(StringUtil.__ISO_8859_1));
                    md.update((byte)':');
                    md.update(realm.getBytes(StringUtil.__ISO_8859_1));
                    md.update((byte)':');
                    md.update(password.getBytes(StringUtil.__ISO_8859_1));
                    ha1=md.digest();
                }
                // calc A2 digest
                md.reset();
                md.update(method.getBytes(StringUtil.__ISO_8859_1));
                md.update((byte)':');
                md.update(uri.getBytes(StringUtil.__ISO_8859_1));
                byte[] ha2=md.digest();
                
                
                
                
                
                // calc digest
                // request-digest  = <"> < KD ( H(A1), unq(nonce-value) ":" nc-value ":" unq(cnonce-value) ":" unq(qop-value) ":" H(A2) ) <">
                // request-digest  = <"> < KD ( H(A1), unq(nonce-value) ":" H(A2) ) > <">

                
                
                md.update(TypeUtil.toString(ha1,16).getBytes(StringUtil.__ISO_8859_1));
                md.update((byte)':');
                md.update(nonce.getBytes(StringUtil.__ISO_8859_1));
                md.update((byte)':');
                md.update(nc.getBytes(StringUtil.__ISO_8859_1));
                md.update((byte)':');
                md.update(cnonce.getBytes(StringUtil.__ISO_8859_1));
                md.update((byte)':');
                md.update(qop.getBytes(StringUtil.__ISO_8859_1));
                md.update((byte)':');
                md.update(TypeUtil.toString(ha2,16).getBytes(StringUtil.__ISO_8859_1));
                byte[] digest=md.digest();
                
                // check digest
                return (TypeUtil.toString(digest,16).equalsIgnoreCase(response));
            }
            catch (Exception e)
            {Log.warn(e);}

            return false;
        }

        public String toString()
        {
            return username+","+response;
        }
        
    }
    /**
     * @return Returns the maxNonceAge.
     */
    public long getMaxNonceAge()
    {
        return maxNonceAge;
    }
    /**
     * @param maxNonceAge The maxNonceAge to set.
     */
    public void setMaxNonceAge(long maxNonceAge)
    {
        this.maxNonceAge = maxNonceAge;
    }
    /**
     * @return Returns the nonceSecret.
     */
    public long getNonceSecret()
    {
        return nonceSecret;
    }
    /**
     * @param nonceSecret The nonceSecret to set.
     */
    public void setNonceSecret(long nonceSecret)
    {
        this.nonceSecret = nonceSecret;
    }

    public void setUseStale(boolean us)
    {
	this.useStale=us;
    }

    public boolean getUseStale()
    {
	return useStale;
    }
}