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Windows SSPI to Java GSSAPI interoperability to achieve SSO on EJB calls

I have Java client running on Windows machine that calls remote EJB
on JBoss EAP/Wildfly running on Linux machine.
I use Kerberos to achieve SSO. Java client verifies the user against Windows domain
and pass his identity within EJB call to the JBoss server.
I started with JAAS and the builtin com.sun.security.auth.module.Krb5LoginModule.
It works correctly except one thing: user has to type his username and password
again. So, it is not a real SSO.
The problem is that Windows prohibits to export kerberos session key from its LSA credential cache.
It can be fixed by setting a specific Windows registry key on each client machine - but this is not acceptable for the customer.
Therefore I am trying to find an alternative solution.
I learned that Windows provides SSPI that shall be interoperable with GSSAPI used by Java. I use Waffle library to access SSPI from Java on the client. On the server I keep using JAAS, because it runs on Linux so I cannot use Waffle there.
I also learned that I don't need to implement LoginModule, rather I need SASL client.
So, I had a look how com.sun.security.sasl.gsskerb.GssKrb5Client works and I am trying to reimplement it using Waffle.
First step seems to work correctly - I obtain SSPI security context from Waffle,
then get the initial token and send it to the server.
The server accepts the token and respond with its own token.
And now the problem comes. In the original SASL client the 'unwrap' operation is
used to extract data from the server token, and 'wrap' operation is used to create
reply token to be sent to server.
GSSAPI wrap / unwrap operations shall correspond to SSPI EncryptMessage / DecryptMessage
operations according to Microsoft doc. This two methods are not available in Waflle, but are available
in NetAccountClient library.
However, I am not able to use them correctly. If I use a single SECBUFFER_STREAM then the DecryptMessage
is succesfull, however the data part of the token is not extracted and I don't know how to determine
the offset where it begins.
If I use SECBUFFER_STREAM and SECBUFFER_DATA as suggested by Microsoft docs, then I get an error:
com.sun.jna.platform.win32.Win32Exception: The message or signature supplied for verification has been altered
I also tried other combinations of SECBUFFER types as suggested elsewhere, but without success.
Any idea what am I doing wrong ?
To source code of unwrap method:
public byte[] unwrap(byte[] wrapper) throws LoginException {
Sspi.SecBuffer.ByReference inBuffer = new Sspi.SecBuffer.ByReference(Secur32Ext.SECBUFFER_STREAM, wrapper);
Sspi.SecBuffer.ByReference buffer = new Sspi.SecBuffer.ByReference();
buffer.BufferType = Sspi.SECBUFFER_DATA;
Secur32Ext.SecBufferDesc2 buffers = new Secur32Ext.SecBufferDesc2(inBuffer, buffer);
NativeLongByReference pfQOP = new NativeLongByReference();
int responseCode = Secur32Ext.INSTANCE.DecryptMessage(secCtx.getHandle(), buffers, new NativeLong(1), pfQOP);
if (responseCode != W32Errors.SEC_E_OK) {
throw handleError(responseCode);
}
byte[] data = buffer.getBytes();
return data;
}

Graph API in SSO is not working in Azure AD

I am trying to develop a Java web application with SSO by following this azure tutorial. I created an account in Azure and created an AD. Developed and deployed the code in Tomcat. When I try to access the page, I am getting the following error
Exception - java.io.IOException: Server returned HTTP response code: 403 for URL: https://graph.windows.net/ppceses.onmicrosoft.com/users?api-version=2013-04-05
I do not find enough answers for this error. I changed the api-version to 1.6. Even then it did not work.
MORE ANALYSIS:
After troubleshooting, I found out that the logged-in user info is fetched and is available in Sessions object. It errors out when its trying to read the response and convert into the String object. Following is the calling method where it errors out.
HttpClientHelper.getResponseStringFromConn(conn, true);
Actual method to write the response into String:
public static String getResponseStringFromConn(HttpURLConnection conn, boolean isSuccess) throws IOException {
BufferedReader reader = null;
if (isSuccess) {
reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
} else {
reader = new BufferedReader(new InputStreamReader(conn.getErrorStream()));
}
StringBuffer stringBuffer = new StringBuffer();
String line = "";
while ((line = reader.readLine()) != null) {
stringBuffer.append(line);
}
return stringBuffer.toString();
}
The actual issue is on the Graphic API where we try to read the response in the String format.

#Anand, According to Microsoft Graph error responses and resource types, the response code 403 means Forbidden below.
Access is denied to the requested resource. The user might not have enough permission.
Please move to the CONFIGURE tab of your application registered in your AAD domain on Azure classic portal, then check whether enable enough permission, please see the figure below.

I got the same error, been struggling with it a few days. What I noticed was that even if I checked ALL permissions for Windows Azure Active Directory I still got the 403. So, I deleted the app in App Registrations and created it again from scratch, generated new application key and readded reply urls. In Required Permissions/Windows Azure Active Directory check:
Sign in and read user profile
Access the directory as the signed-in user
I can now call me/memberOf successfully.
Hope it helps.

The below worked for me.
At the active directory app registrations -> app ->settings->permissions-> enable delegate permissions to read directory data. Save and close the blade. Also Click Grant Permissions and close the blade.
Once the above is done, Log out and Log in back with a fresh token to the application. (Guess the token with prior authorizations will not reflect the latest permission changes and hence the re-login may have worked in my case)

Accessing kerberos secured WebHDFS without SPnego

I have a working application for managing HDFS using WebHDFS.
I need to be able to do this on a Kerberos secured cluster.
The problem is, that there is no library or extension to negotiate the ticket for my app, I only have a basic HTTP client.
Would it be possible to create a Java service which would handle the ticket exchange and once it gets the Service ticket to just pass it to the app for use in a HTTP request?
In other words, my app would ask the Java service to negotiate the tickets and it would return the Service ticket back to my app in a string or raw string and the app would just attach it to the HTTP request?
EDIT: Is there a similar elegant solution like #SamsonScharfrichter described for HTTPfs? (To my knowledge, it does not support delegation tokens)
EDIT2: Hi guys, I am still completly lost. Im trying to figure out the Hadoop-auth client without any luck. Could you please help me out again? I already spent hours reading upon it without luck.
The examples say to do this:
* // establishing an initial connection
*
* URL url = new URL("http://foo:8080/bar");
* AuthenticatedURL.Token token = new AuthenticatedURL.Token();
* AuthenticatedURL aUrl = new AuthenticatedURL();
* HttpURLConnection conn = new AuthenticatedURL(url, token).openConnection();
* ....
* // use the 'conn' instance
* ....
Im lost already here. What initial connection do I need? How can
new AuthenticatedURL(url, token).openConnection();
take two parameters? there is no constructor for such a case. (im getting error because of this). Shouldnt a principal be somewhere specified? It is probably not going to be this easy.
URL url = new URL("http://<host>:14000/webhdfs/v1/?op=liststatus");
AuthenticatedURL.Token token = new AuthenticatedURL.Token();
HttpURLConnection conn = new AuthenticatedURL(url, token).openConnection(url, token);

Using Java code plus the Hadoop Java API to open a Kerberized session, get the Delegation Token for the session, and pass that Token to the other app -- as suggested by #tellisnz -- has a drawback: the Java API requires quite a lot of dependencies (i.e. a lot of JARs, plus Hadoop native libraries). If you run you app on Windows, in particular, it will be a tough ride.
Another option is to use Java code plus WebHDFS to run a single SPNEGOed query and GET the Delegation Token, then pass it to the other app -- that option requires absolutely no Hadoop library on your server. The barebones version would be sthg like
URL urlGetToken = new URL("http://<host>:<port>/webhdfs/v1/?op=GETDELEGATIONTOKEN") ;
HttpURLConnection cnxGetToken =(HttpURLConnection) urlGetToken.openConnection() ;
BufferedReader httpMessage = new BufferedReader( new InputStreamReader(cnxGetToken.getInputStream()), 1024) ;
Pattern regexHasToken =Pattern.compile("urlString[\": ]+(.[^\" ]+)") ;
String httpMessageLine ;
while ( (httpMessageLine =httpMessage.readLine()) != null)
{ Matcher regexToken =regexHasToken.matcher(httpMessageLine) ;
if (regexToken.find())
{ System.out.println("Use that template: http://<Host>:<Port>/webhdfs/v1%AbsPath%?delegation=" +regexToken.group(1) +"&op=...") ; }
}
httpMessage.close() ;
That's what I use to access HDFS from a Windows Powershell script (or even an Excel macro). Caveat: with Windows you have to create your Kerberos TGT on the fly, by passing to the JVM a JAAS config pointing to the appropriate keytab file. But that caveat also applies to the Java API, anyway.

You could take a look at the hadoop-auth client and create a service which does the first connection, then you might be able to grab the 'Authorization' and 'X-Hadoop-Delegation-Token' headers and cookie from it and add it to your basic client's requests.
First you'll need to have either used kinit to authenticate your user for application before running. Otherwise, you're going to have to do a JAAS login for your user, this tutorial provides a pretty good overview on how to do that.
Then, to do the login to WebHDFS/HttpFS, we'll need to do something like:
URL url = new URL("http://youhost:8080/your-kerberised-resource");
AuthenticatedURL.Token token = new AuthenticatedURL.Token();
HttpURLConnection conn = new AuthenticatedURL().openConnection(url, token);
String authorizationTokenString = conn.getRequestProperty("Authorization");
String delegationToken = conn.getRequestProperty("X-Hadoop-Delegation-Token");
...
// do what you have to to get your basic client connection
...
myBasicClientConnection.setRequestProperty("Authorization", authorizationTokenString);
myBasicClientConnection.setRequestProperty("Cookie", "hadoop.auth=" + token.toString());
myBasicClientConnection.setRequestProperty("X-Hadoop-Delegation-Token", delegationToken);

Response code 401 when accesing rest based web services with correct credentials

I am getting Unauthorized error when accessing restful web services. My sample program looks like this.
public static void main(String[] args){
// Use apache commons-httpclient to create the request/response
HttpClient client = new HttpClient();
Credentials defaultcreds = new UsernamePasswordCredentials("aaa", "cdefg");
client.getState().setCredentials(AuthScope.ANY, defaultcreds);
GetMethod method = new GetMethod(
"http://localhost:8080/userService/usersByID/1234");
try {
client.executeMethod(method);
InputStream in = method.getResponseBodyAsStream();
// Use dom4j to parse the response and print nicely to the output stream
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
StringBuilder out = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
out.append(line);
}
System.out.println(out.toString());
} catch (IOException e) {
e.printStackTrace();
}
}
My credentials are correct. My web services will consume Basic Http Authentication.
I have doubt at scope of authentication.
client.getState().setCredentials(AuthScope.ANY, defaultcreds);
My credentials are correct.
Can any one help to resolve this issue.
Thanks.

First check your url via browser and verify ?? as mentioned here
Fixing 401 errors - general
Each Web Server manages user authentication in its own way. A security officer (e.g. a Web Master) at the site typically decides which users are allowed to access the URL. This person then uses Web server software to set up those users and their passwords. So if you need to access the URL (or you forgot your user ID or password), only the security officer at that site can help you. Refer any security issues direct to them.
If you think that the URL Web page *should* be accessible to all and sundry on the Internet, then a 401 message indicates a deeper problem. The first thing you can do is check your URL via a Web browser. This browser should be running on a computer to which you have never previously identified yourself in any way, and you should avoid authentication (passwords etc.) that you have used previously. Ideally all this should be done over a completely different Internet connection to any you have used before (e.g. a different ISP dial-up connection). In short, you are trying to get the same behaviour a total stranger would get if they surfed the Internet to the Web page.
If this type of browser check indicates no authority problems, then it is possible that the Web server (or surrounding systems) have been configured to disallow certain patterns of HTTP traffic. In other words, HTTP communication from a well-known Web browser is allowed, but automated communication from other systems is rejected with an 401 error code. This is unusual, but may indicate a very defensive security policy around the Web server.
Manual Fix
Hit the url from the browser and record the HTTP traffic (Headers,body)
Run the Java client code and record the HTTP traffic (Headers,body)
Analyze and fix the differences

Simple Kerberos client in Java?

Applications such a Google's Chrome and IE can transparently handle Kerberos authentication; however I can not find a "simple" Java solution to match this transparency. All of the solutions I have found require the presence of a krb5.conf file and a login.conf file which nether of the above apps seem to require.
What is the best way to build a Java application with Kerberos SSO capabilities that just work?
[update]: to be clear I need a CLIENT side solution for creating tickets not validating them. Also, it seems that SPNEGO is the default "wrapper" protocol that will eventually delegate to Kerberos but I need to be able to handle the SPNEGO protocol as well.

There is now a simple solution for this using the Apache HTTP Components Client 4.5 or greater. This is still marked as experimental in 4.5 so your milage may vary, but this is working fine for me in an enterprise context.
In addition to the HC 4.5 client jars you will need to have the httpclient-win, jna and jna-platform jars on your classpath, as provided with http-component-client. You then construct a Kerberos enabled HC-client as follows:
CloseableHttpClient httpclient = WinHttpClients.createDefault();
Or using the builder:
HttpClientBuilder clientBuilder = WinHttpClients.custom();
Which can then be customised as required before building the client:
CloseableHttpClient client = clientBuilder.build();
This solution works without any external configuration, and most importantly solves the issue where the in-built JRE mechanism breaks for users with local Admin rights on Windows 7+. This is possible because the Kerberos ticket is being retrieved directly from the SSPI API via JNA, rather than going through the GSSAPI provided by the JRE.
Example code from the http-components team
This was all made possible by the good work of Daniel Doubrovkine Timothy Wall
and Ryan McKinley

Adding to David Roussels answer on url specific http based kerberos authentication:-
The reason why your code works is because your target SPN(server side principal) is configured to with HTTP/serverhostname.realm.com#DOMAIN.COM. In that case it will work because you are not explicitly setting the token. URLConnection internally sets a token with that SPN
1 Perform steps(from my previous answer) to get a subject
2 Use gss api init sec context to generate a context token. There are numerous tutorials out there for this step
3 Base 64 encode the token
4 Attach the token to urlconnection:-
URL url = new URL("http://myhost/myapp")
HttpURLConnection urlConn = (HttpURLConnection)url.openConnection(); =
urlConn.setRequestProperty("Authorization", "Negotiate " + encodedToken);
5 Implement a priviledged action:-
//this internally calls the getInputStream
public class PrivilegedGetInputStream implements PrivilegedExceptionAction<InputStream>
6 Wrap the whole thing in Subject.doAs
//use prev answer instructions to get subject
Subject.doAs(subject, new PrivilegedGetInputStream(urlConnection)

Oracle has an example using Java's SaslClient. I'm not a Java programmer, but when I pointed this out once to someone who is, they were able to make it work pretty quickly. It may still require a "conf" file somewhere (n.b. Kerberos uses environment variables, often starting with KRB5_, to know where to look for such files). Also note that Kerberos itself does not include a transport of any kind--your app needs to know how to send and receive the Kerberos payloads the way the server expects (and this is different depending on the server you are trying to authenticate with).
Edit: you edited your question, so here's a link related to SPNEGO in Java which might be of some use:
http://download.oracle.com/javase/6/docs/technotes/guides/security/jgss/lab/part5.html

You don't actually need to do anything. In Java 6, on a Windows client machine you can do this:
new URL("http://myhost/myapp").openStream();
And negotiate authentication just works. At least it does for me. And the server I tested on only supports Negotiate, not NTLM auth.

Ok if you want to avoid using a login.conf file you need to code differently:-
//define your own configuration
import javax.security.auth.login.Configuration;
public class CustomLoginConfiguration extends Configuration
//pass certain parameters to its constructor
//define an config entry
import javax.security.auth.login.AppConfigurationEntry;
private AppConfigurationEntry configEntry;
//define a map of params you wish to pass and fill them up
//the map contains entries similar to one you have in login.conf
Map<String, String> params = new HashMap<String, String>();
//define the configuration
configEntry = new AppConfigurationEntry(
"com.sun.security.auth.module.Krb5LoginModule",
AppConfigurationEntry.LoginModuleControlFlag.REQUIRED, params);
//implement getappconfig method
public AppConfigurationEntry[] getAppConfigurationEntry() {
return new AppConfigurationEntry[] { configEntry };
}
Now once you are done with this definition you can use this in you use this to fetch tickets from kdc
//get ticket in login context
LoginContext lc = null;
lc = new LoginContext("lc", null, callback, new CustomLoginConfiguration(argumentlist));
lc.login();
Now from here on you can fetch jaas subject and can basically do a ton of authentication stuff.
In case you need further pointers just leave a comment.

You can use system properties instead of config files to specify the KDC hostname and service name, but those things (at least) are mandatory....
Waffle will actually give you the information you need to set most of the properties, even if it won't get you a ticket. Look at the WindowsAuthProviderImpl class (the Waffle.chm help file shows the API).
I use JAAS do obtain a service ticket from Active Directory in two steps:
Use Krb5LoginModule to retrieve the cached TGT and add it to the Subject.
Use the Subject and GSS-API to retrieve a service ticket from the KDC.
There's a lot of good information and example code at The Java Way of Active Directory.

I created a small tool to simplify connecting with httpclient to kerberos, you might want to give it a try.
https://github.com/DovAmir/httpclientAuthHelper
DefaultHttpClient httpclient = new DefaultHttpClient();
AuthUtils.securityLogging(SecurityLogType.KERBEROS,true);
CredentialsUtils.setKerberosCredentials(client, new UsernamePasswordCredentials("xxx", "xxx"), "domain", "kdc");
client.executeMethod(httpget);

Use WAFFLE

Here's a good blog post on having a java client to use with Kerberos
http://sachithdhanushka.blogspot.com/2014/02/kerberos-java-client-configuration.html