org.apache.catalina.authenticator.DigestAuthenticator Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.catalina.authenticator;
import java.io.IOException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.Principal;
import java.util.StringTokenizer;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.catalina.Realm;
import org.apache.catalina.connector.Request;
import org.apache.catalina.deploy.LoginConfig;
import org.apache.catalina.util.MD5Encoder;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
/**
* An Authenticator and Valve implementation of HTTP DIGEST
* Authentication (see RFC 2069).
*
* @author Craig R. McClanahan
* @author Remy Maucherat
* @version $Id: DigestAuthenticator.java 1043105 2010-12-07 15:42:32Z markt $
*/
public class DigestAuthenticator
extends AuthenticatorBase {
private static final Log log = LogFactory.getLog(DigestAuthenticator.class);
// -------------------------------------------------------------- Constants
/**
* The MD5 helper object for this class.
*/
protected static final MD5Encoder md5Encoder = new MD5Encoder();
/**
* Descriptive information about this implementation.
*/
protected static final String info =
"org.apache.catalina.authenticator.DigestAuthenticator/1.0";
// ----------------------------------------------------------- Constructors
public DigestAuthenticator() {
super();
try {
if (md5Helper == null)
md5Helper = MessageDigest.getInstance("MD5");
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
throw new IllegalStateException();
}
}
// ----------------------------------------------------- Instance Variables
/**
* MD5 message digest provider.
*/
protected static volatile MessageDigest md5Helper;
/**
* Private key.
*/
protected String key = "Catalina";
// ------------------------------------------------------------- Properties
/**
* Return descriptive information about this Valve implementation.
*/
@Override
public String getInfo() {
return (info);
}
// --------------------------------------------------------- Public Methods
/**
* Authenticate the user making this request, based on the specified
* login configuration. Return true if any specified
* constraint has been satisfied, or false if we have
* created a response challenge already.
*
* @param request Request we are processing
* @param response Response we are creating
* @param config Login configuration describing how authentication
* should be performed
*
* @exception IOException if an input/output error occurs
*/
@Override
public boolean authenticate(Request request,
HttpServletResponse response,
LoginConfig config)
throws IOException {
// Have we already authenticated someone?
Principal principal = request.getUserPrincipal();
//String ssoId = (String) request.getNote(Constants.REQ_SSOID_NOTE);
if (principal != null) {
if (log.isDebugEnabled())
log.debug("Already authenticated '" + principal.getName() + "'");
// Associate the session with any existing SSO session in order
// to get coordinated session invalidation at logout
String ssoId = (String) request.getNote(Constants.REQ_SSOID_NOTE);
if (ssoId != null)
associate(ssoId, request.getSessionInternal(true));
return (true);
}
// NOTE: We don't try to reauthenticate using any existing SSO session,
// because that will only work if the original authentication was
// BASIC or FORM, which are less secure than the DIGEST auth-type
// specified for this webapp
//
// Uncomment below to allow previous FORM or BASIC authentications
// to authenticate users for this webapp
// TODO make this a configurable attribute (in SingleSignOn??)
/*
// Is there an SSO session against which we can try to reauthenticate?
if (ssoId != null) {
if (log.isDebugEnabled())
log.debug("SSO Id " + ssoId + " set; attempting " +
"reauthentication");
// Try to reauthenticate using data cached by SSO. If this fails,
// either the original SSO logon was of DIGEST or SSL (which
// we can't reauthenticate ourselves because there is no
// cached username and password), or the realm denied
// the user's reauthentication for some reason.
// In either case we have to prompt the user for a logon
if (reauthenticateFromSSO(ssoId, request))
return true;
}
*/
// Validate any credentials already included with this request
String authorization = request.getHeader("authorization");
if (authorization != null) {
principal = findPrincipal(request, authorization, context.getRealm());
if (principal != null) {
String username = parseUsername(authorization);
register(request, response, principal,
Constants.DIGEST_METHOD,
username, null);
return (true);
}
}
// Send an "unauthorized" response and an appropriate challenge
// Next, generate a nOnce token (that is a token which is supposed
// to be unique).
String nOnce = generateNOnce(request);
setAuthenticateHeader(request, response, config, nOnce);
response.sendError(HttpServletResponse.SC_UNAUTHORIZED);
// hres.flushBuffer();
return (false);
}
@Override
protected String getAuthMethod() {
return Constants.DIGEST_METHOD;
}
// ------------------------------------------------------ Protected Methods
/**
* Parse the specified authorization credentials, and return the
* associated Principal that these credentials authenticate (if any)
* from the specified Realm. If there is no such Principal, return
* null.
*
* @param request HTTP servlet request
* @param authorization Authorization credentials from this request
* @param realm Realm used to authenticate Principals
*/
protected static Principal findPrincipal(Request request,
String authorization,
Realm realm) {
//System.out.println("Authorization token : " + authorization);
// Validate the authorization credentials format
if (authorization == null)
return (null);
if (!authorization.startsWith("Digest "))
return (null);
authorization = authorization.substring(7).trim();
// Bugzilla 37132: http://issues.apache.org/bugzilla/show_bug.cgi?id=37132
String[] tokens = authorization.split(",(?=(?:[^\"]*\"[^\"]*\")+$)");
String userName = null;
String realmName = null;
String nOnce = null;
String nc = null;
String cnonce = null;
String qop = null;
String uri = null;
String response = null;
String method = request.getMethod();
for (int i = 0; i < tokens.length; i++) {
String currentToken = tokens[i];
if (currentToken.length() == 0)
continue;
int equalSign = currentToken.indexOf('=');
if (equalSign < 0)
return null;
String currentTokenName =
currentToken.substring(0, equalSign).trim();
String currentTokenValue =
currentToken.substring(equalSign + 1).trim();
if ("username".equals(currentTokenName))
userName = removeQuotes(currentTokenValue);
if ("realm".equals(currentTokenName))
realmName = removeQuotes(currentTokenValue, true);
if ("nonce".equals(currentTokenName))
nOnce = removeQuotes(currentTokenValue);
if ("nc".equals(currentTokenName))
nc = removeQuotes(currentTokenValue);
if ("cnonce".equals(currentTokenName))
cnonce = removeQuotes(currentTokenValue);
if ("qop".equals(currentTokenName))
qop = removeQuotes(currentTokenValue);
if ("uri".equals(currentTokenName))
uri = removeQuotes(currentTokenValue);
if ("response".equals(currentTokenName))
response = removeQuotes(currentTokenValue);
}
if ( (userName == null) || (realmName == null) || (nOnce == null)
|| (uri == null) || (response == null) )
return null;
// Second MD5 digest used to calculate the digest :
// MD5(Method + ":" + uri)
String a2 = method + ":" + uri;
//System.out.println("A2:" + a2);
byte[] buffer = null;
synchronized (md5Helper) {
buffer = md5Helper.digest(a2.getBytes());
}
String md5a2 = md5Encoder.encode(buffer);
return (realm.authenticate(userName, response, nOnce, nc, cnonce, qop,
realmName, md5a2));
}
/**
* Parse the username from the specified authorization string. If none
* can be identified, return null
*
* @param authorization Authorization string to be parsed
*/
protected String parseUsername(String authorization) {
//System.out.println("Authorization token : " + authorization);
// Validate the authorization credentials format
if (authorization == null)
return (null);
if (!authorization.startsWith("Digest "))
return (null);
authorization = authorization.substring(7).trim();
StringTokenizer commaTokenizer =
new StringTokenizer(authorization, ",");
while (commaTokenizer.hasMoreTokens()) {
String currentToken = commaTokenizer.nextToken();
int equalSign = currentToken.indexOf('=');
if (equalSign < 0)
return null;
String currentTokenName =
currentToken.substring(0, equalSign).trim();
String currentTokenValue =
currentToken.substring(equalSign + 1).trim();
if ("username".equals(currentTokenName))
return (removeQuotes(currentTokenValue));
}
return (null);
}
/**
* Removes the quotes on a string. RFC2617 states quotes are optional for
* all parameters except realm.
*/
protected static String removeQuotes(String quotedString,
boolean quotesRequired) {
//support both quoted and non-quoted
if (quotedString.length() > 0 && quotedString.charAt(0) != '"' &&
!quotesRequired) {
return quotedString;
} else if (quotedString.length() > 2) {
return quotedString.substring(1, quotedString.length() - 1);
} else {
return "";
}
}
/**
* Removes the quotes on a string.
*/
protected static String removeQuotes(String quotedString) {
return removeQuotes(quotedString, false);
}
/**
* Generate a unique token. The token is generated according to the
* following pattern. NOnceToken = Base64 ( MD5 ( client-IP ":"
* time-stamp ":" private-key ) ).
*
* @param request HTTP Servlet request
*/
protected String generateNOnce(Request request) {
long currentTime = System.currentTimeMillis();
String nOnceValue = request.getRemoteAddr() + ":" +
currentTime + ":" + key;
byte[] buffer = null;
synchronized (md5Helper) {
buffer = md5Helper.digest(nOnceValue.getBytes());
}
nOnceValue = md5Encoder.encode(buffer);
return nOnceValue;
}
/**
* Generates the WWW-Authenticate header.
*
* The header MUST follow this template :
*
* WWW-Authenticate = "WWW-Authenticate" ":" "Digest"
* digest-challenge
*
* digest-challenge = 1#( realm | [ domain ] | nOnce |
* [ digest-opaque ] |[ stale ] | [ algorithm ] )
*
* realm = "realm" "=" realm-value
* realm-value = quoted-string
* domain = "domain" "=" <"> 1#URI <">
* nonce = "nonce" "=" nonce-value
* nonce-value = quoted-string
* opaque = "opaque" "=" quoted-string
* stale = "stale" "=" ( "true" | "false" )
* algorithm = "algorithm" "=" ( "MD5" | token )
*
*
* @param request HTTP Servlet request
* @param response HTTP Servlet response
* @param config Login configuration describing how authentication
* should be performed
* @param nOnce nonce token
*/
protected void setAuthenticateHeader(HttpServletRequest request,
HttpServletResponse response,
LoginConfig config,
String nOnce) {
// Get the realm name
String realmName = config.getRealmName();
if (realmName == null)
realmName = REALM_NAME;
byte[] buffer = null;
synchronized (md5Helper) {
buffer = md5Helper.digest(nOnce.getBytes());
}
String authenticateHeader = "Digest realm=\"" + realmName + "\", "
+ "qop=\"auth\", nonce=\"" + nOnce + "\", " + "opaque=\""
+ md5Encoder.encode(buffer) + "\"";
response.setHeader(AUTH_HEADER_NAME, authenticateHeader);
}
}