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Hyperledger fabric endorsement policy error using Java SDK

I am working on golang version of fabcar smart contract while seeking to implement a Java-SDK API which enrolls an admin, registers a user and performs query-update value operations based on https://github.com/hyperledger/fabric-samples/tree/master/fabcar/java
I have successfully set up a 3 org-9 peers blockchain network, installed, instantiated and invoked chaincode on peers.
However, as i am working on implementing the relative API, i am only able to successfully query blockchain database, while getting a "Could not meet endorsement policy for chaincode mycc"
Please find below screenshot of relative error
Endorsement policy is "OR ('Org1MSP.member','Org2MSP.member', 'Org3MSP.member')".
Should registered user somehow get an Org1/Org2/Org3.member attribute? Any leads would be appreciated!

Like #Ikar Pohorský said, for me this got resolved after I used correct method name. Also, ensure that you delete 'wallet' folder in order to regenerate the user if your HLF n/w was recreated.
#Test
public void testMyMethodToBeInvoked() throws Exception {
deleteDirectory(".\\wallet");
EnrollAdmin.main(null);
RegisterUser.main(null);
// Load a file system based wallet for managing identities.
final Path walletPath = Paths.get("wallet");
final Wallet wallet = Wallet.createFileSystemWallet(walletPath);
// load a CCP
final Path networkConfigPath = Paths
.get("C:\\sw\\hlf146-2\\fabric-samples\\first-network\\connection-org1.yaml");
final Gateway.Builder builder = Gateway.createBuilder();
builder.identity(wallet, "user1").networkConfig(networkConfigPath).discovery(true);
// create a gateway connection
try (Gateway gateway = builder.connect()) {
final Network network = gateway.getNetwork("mychannel");
final Contract contract = network.getContract("mycc");
String myJSONString="{\"a\":\"b\"}";
byte[] result;
// Following did NOT work. Control goes directly to 'invoke' when 'submitTransaction' is done directly. 'invoke' need not be mentioned here.
// result = contract.submitTransaction("invoke", myJSONString);
// Following DID work. In chaincode (my chain code was Java) I had a method named 'myMethodToBeInvoked'. The chain code was written similar to https://github.com/hyperledger/fabric-samples/blob/release-1.4/chaincode/chaincode_example02/java/src/main/java/org/hyperledger/fabric/example/SimpleChaincode.java
result = contract.submitTransaction("myMethodToBeInvoked", my);
System.out.println(new String(result));
}
}
EDIT: Also, please remember that if your chaincode throws errorResponse, even then we can have this endorsement fail issue. So, check if your chain code is working without any issues.

Problem Implementing a custom Keycloak Authenticator SPI

I'm trying to implement a custom keycloack Authenticator SPI for authentication purposes against an external Identity provider. The users already exist on the keycloak store, I only need connection to the custom SPI to authenticate them.
I'm following section 8.3 of the official guide https://www.keycloak.org/docs/latest/server_development/index.html#_auth_spi_walkthrough, which is very similar to what I need.
The problem I'm running into is that after the authentication flow runs into the "action" method of the custom Authenticator, an exception is thrown from the AuthenticationProcessor Class, which after inspection, comes from following check:
// org.keycloak.authentication.AuthenticationProcessor - line 876
if (authenticationSession.getAuthenticatedUser() == null) {
throw new AuthenticationFlowException(AuthenticationFlowError.UNKNOWN_USER);
}
after seeing this problem, my idea for trying solving it, was getting the user (already verified against the externl Identity Provider) from the keycloak store, and pushing it into the AuthenticationSession, like this:
// Connect against external Service Provider
// and asume "USER_ID" represents an already validated User
// AuthenticationFlowContext = afc is given as parameter
UserFederationManager ufm = afc.getSession().users(); // <-- PROBLEM
UserModel userFound = ufm.getUserById("USER_ID", afc.getRealm());
if (userFound != null) {
// get reference to the authSession
AuthenticationSessionModel asm = afc.getAuthenticationSession();
// set authenticated user on the session
asm.setAuthenticatedUser(userFound );
return true;
}
return false;
The problem with the above code, is that a Java NoSuchMethodExceptionError is thrown regarding the users() method of the org.keaycloak.models.KeycloackSession class. Like this:
11:26:32,628 ERROR [org.keycloak.services.error.KeycloakErrorHandler] (default task-14) Uncaught server error: java.lang.NoSuchMethodError: org.keycloak.models.KeycloakSession.users()Lorg/keycloak/models/UserFederationManager;
Any suggestion that you could make to help me solve this would be greatly appreciated!

It seems the problem was that I was using an org.keycloak.models.UserFederationManager instance, instead of an org.keycloak.models.UserProvider instance. The UserFederationManager implements the UserProvider, and it seems the more general type works better than the more specific type under the injection mechanism this keycloak is using
// UserFederationManager ufm = afc.getSession().users(); // <-- PROBLEM
// UserProvider ufm = afc.getSession().users(); // <-- WORKS
Even though it works now, both of your suggestions are valid because my build version is indeed diferent that the one on the runtime, I'll solve that to avoid further Bugs.
Thanks your input Guys!

As Henry stated, it's likely to be a version conflict. I had a similar problem which was solved with this thread's help. It suggests you downgrade some dependencies version, but in my case, we solved it changing back our server to Tomcat.

Single Sign-On with Java Client

I am looking for a Single Sign-On authentication in a Java client.
Since I am logged in to Windows using an AD, the main goal is that I do not have to enter username and password again. I want Java to use the Ticket I recieved at Windows-login. This code is the best I have for the purpose:
LoginContext lc = new LoginContext("com.sun.security.jgss.krb5.initiate", new DialogCallbackHandler());
lc.login();
Subject.doAs(lc.getSubject(), (PrivilegedExceptionAction<Void>) () -> {
System.out.println("This is privileged");
return null;
});
I've set the java.security.krb5.conf and java.security.auth.login.config properties with corresponding conf-files, but still a dialog asking for Username and Password pops up.
I also tried working with GSSName, but GSSManager.createCredential() is also asking for Username and Password (probably using the TextCallbackHandler()).
I tried to get along with Waffle, but did not get it working. Most examples and explanations are Server sided (I only found one example combining server and client side, but I was not able to split it up).
I know, there are Similar questions (e.g. this), but i did not get that working without entering a password.
PS: i know, that DialogCallbackHandler is depricated, I use it for test purposes only.

Ok, after several tries I found a solution. The problem was not in the code, but in the registry. As stated on this page, since Java 7 You can't access the ticket of Windows natively. To change this, You have to set an additional registry key. For this, go into the registry folder
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Lsa\Kerberos\Parameters
and add the key
Value Name: AllowTgtSessionKey
Value Type: REG_DWORD
Value: 0x01
To fully make this work you will need some additional settings:
The jaas configuration file
In the jaas configuration file you have to set up which security modules jaas should use. The part in front of the brackets names your configuration. If you use the GSS libraries you must name it com.sun.security.jgss.krb5.initiate. When you use the LoginContext you just pass the name of the configuration as first parameter. My jaas.conf look as follows:
com.sun.security.jgss.krb5.initiate {
com.sun.security.auth.module.Krb5LoginModule required
useTicketCache = true;
};
The kerberos configuration
You will also need a configuration for the Kerberos module. This mainly contains the realm address, but can hold additional information. A minimal working example:
[realms]
YOUR.REALM.COM = {
kdc = your.realm.com:88
default_domain = REALM.COM
}
Note, that this is case sensitive!
The System Properties
Finally, you have to set up Java to find this files. You do this either by giving the properties on startup or by calling System.setProperty():
System.setProperty("java.security.krb5.conf", "src/resources/krb5.conf");
System.setProperty("java.security.auth.login.config", "src/resources/jaas.conf");

Java GSS-API Service Ticket not saved in Credentials Cache using Java

I have created 2 demo Kerberos Clients using the GSS-API.
One in Python3, the second in Java.
Both clients seem to be broadly equivalent, and both "work" in that I get a service ticket that is accepted by my Java GSS-API Service Principal.
However on testing I noticed that the Python client saves the service ticket in the kerberos credentials cache, whereas the Java client does not seem to save the ticket.
I use "klist" to view the contents of the credential cache.
My clients are running on a Lubuntu 17.04 Virtual Machine, using FreeIPA as the Kerberos environment. I am using OpenJDK 8 u131.
Question 1: Does the Java GSS-API not save service tickets to the credentials cache? Or can I change my code so it does so?
Question 2: Is there any downside to the fact that the service ticket is not saved to the cache?
My assumption is that cached service tickets reduce interaction with the KDC, but comments on How to save Kerberos Service Ticket using a Windows Java client? suggest that is not the case, but this Microsoft technote says "The client does not need to go back to the KDC each time it wants access to this particular server".
Question 3: The cached service tickets from the python client vanish after some minutes - long before the expiry date. What causes them to vanish?
Python code
#!/usr/bin/python3.5
import gssapi
from io import BytesIO
server_name = 'HTTP/app-srv.acme.com#ACME.COM'
service_name = gssapi.Name(server_name)
client_ctx = gssapi.SecurityContext(name=service_name, usage='initiate')
initial_client_token = client_ctx.step()
Java Code
System.setProperty("java.security.krb5.conf","/etc/krb5.conf");
System.setProperty("javax.security.auth.useSubjectCredsOnly","false");
GSSManager manager = GSSManager.getInstance();
GSSName clientName;
GSSContext context = null;
//try catch removed for brevity
GSSName serverName =
manager.createName("HTTP/app-srv.acme.com#ACME.COM", null);
Oid krb5Oid = new Oid("1.2.840.113554.1.2.2");
//use default credentials
context = manager.createContext(serverName,
krb5Oid,
null,
GSSContext.DEFAULT_LIFETIME);
context.requestMutualAuth(false);
context.requestConf(false);
context.requestInteg(true);
byte[] token = new byte[0];
token = context.initSecContext(token, 0, token.length);
Edit:
While the original question focusses on the use of the Java GSS-API to build a Java Kerberos Client, GSS is not a must. I am open to other Kerberos approaches that work on Java. Right now I am experimenting with Apache Kerby kerb-client.
So far Java GSS-API seems to have 2 problems:
1) It uses the credentials cache to get the TGT (Ok), but not to cache service-tickets (Not Ok).
2) It cannot access credential caches of type KEYRING. (Confirmed by behaviour, debugging the Java runtime security classes, and by comments in that code. For the Lubuntu / FreeIPA combination I am using KEYRING was the out-of-the-box default. This won't apply to Windows, and may not apply to other Linux Kerberos combinations.

Edit 2:
The question I should have asked is:
How do I stop my KDC from being hammered for repeated SGT requests because Java GSS is not using the credentials cache.
I leave my original answer in place at the bottom, because if largely focusses on the original question.
After another round of deep debugging and testing, I have found an acceptable solution to the root problem.
Using Java GSS API with JAAS, as opposed to "pure" GSS without JAAS in my original solution makes a big difference!
Yes, existing Service Tickets (SGTs) that may be in the credentials cache are not being loaded,
nor are any newly acquired SGTs written back to the cache, however the KDC is not be constantly hammered (the real problem).
Both pure GSS, and GSS with JAAS use a client principal subject. The subject has an in-memory privateCredentials set,
which is used to store TGTs and SGTs.
The key difference is:
"pure GSS": the subject + privateCredentials is created within the GSSContext, and lives only as long as the GSSContext lives.
GSS with JAAS: the subject is created by JAAS, outside the GSSContext, and thus can live for the life of the application,
spanning many GSSContexts during the life of the application.
The first GSSContext established will query the subject's privateCredentials for a SGT, not find one,
then request a SGT from the KDC.
The SGT is added to the subject's privateCredentials, and as the subject lives longer than the GSSContext,
it is available, as is the SGT, when following GSSContexts are created. These will find the SGT in the subject's privateCredentials, and do not need to hit the KDC for a new SGT.
So seen in the light of my particular Java Fat Client, opened once and likely to run for hours, everything is ok.
The first GSSContext created will hit the KDC for a SGT which will then be used by all following GSSContexts created until the client is closed.
The credentials cache is not being used, but that does not hurt.
In the light of a much shorter lived client, reopened many many times, and perhaps in parallel,
then use / non-use of the credentials cache might be a more serious issue.
private void initJAASandGSS() {
LoginContext loginContext = null;
TextCallbackHandler cbHandler = new TextCallbackHandler();
try {
loginContext = new LoginContext("wSOXClientGSSJAASLogin", cbHandler);
loginContext.login();
mySubject = loginContext.getSubject();
} catch (LoginException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
gssManager = GSSManager.getInstance();
try {
//TODO: LAMB: This name should be got from config / built from config / serviceIdentifier
serverName = gssManager.createName("HTTP/app-srv.acme.com#ACME.COM", null);
Oid krb5Oid = new Oid("1.2.840.113554.1.2.2");
} catch (GSSException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private String getGSSwJAASServiceToken() {
byte[] token = null;
String encodedToken = null;
token = Subject.doAs(mySubject, new PrivilegedAction<byte[]>(){
public byte[] run(){
try{
System.setProperty("javax.security.auth.useSubjectCredsOnly","true");
GSSContext context = gssManager.createContext(serverName,
krb5Oid,
null,
GSSContext.DEFAULT_LIFETIME);
context.requestMutualAuth(false);
context.requestConf(false);
context.requestInteg(true);
byte[] ret = new byte[0];
ret = context.initSecContext(ret, 0, ret.length);
context.dispose();
return ret;
} catch(Exception e){
Log.log(Log.ERROR, e);
throw new otms.util.OTMSRuntimeException("Start Client (Kerberos) failed, cause: " + e.getMessage());
}
}
});
encodedToken = Base64.getEncoder().encodeToString(token);
return encodedToken;
}
End Edit 2: Original answer below:
Question 1: Does the Java GSS-API not save service tickets to the credentials cache? Or can I change my code so it does so?
Edit: Root Cause Analysis.
After many hours debugging the sun.security.* classes, I now understand what GSS and Java Security code is doing / not doing - at least in Java 8 u 131.
In this example we have a credential cache, of a type Java GSS can access, containing a valid Ticket Granting Ticket (TGT) and a valid Service Ticket (SGT).
1) When the client principal Subject is created, the TGT is loaded from the cache (Credentials.acquireTGTFromCache()), and stored in the privateCredentials set of the Subject. --> (OK)
Only the TGT is loaded, SGTs are NOT loaded and saved to the Subject privateCredentials. -->(NOT OK)
2) Later, deep in the GSSContext.initSecContext() process, the security code actually tries to retrieve a Service Ticket from the privateCredentials of the Subject. The relevant code is Krb5Context.initSecContext() / KrbUtils.getTicket() / SubjectComber.find()/findAux(). However as SGTs were never loaded in step 1) an SGT will not be found! Therefore a new SGT is requested from the KDC and used.
This is repeated for each Service request.
Just for fun, and strictly as a proof-of-concept hack, I added a few lines of code between the login, and the initSecContext() to parse the credentials cache, extract the credentials, convert to Krb Credentials, and add them to the Subject’s private credentials.
This done, in step 2) the existing SGT is found and used. No new SGT is requested from the KDC.
I will not post the code for this hack as it calls sun internal classes that we should not be calling, and I don’t wish to inspire anybody else to do so. Nor do I intend to use this hack as a solution.
—> The root cause problem is not that the service ticket are not SAVED to the cache; but rather
a) that SGTs are not LOADED from the credential cache to the Subject of the client principal
and
b) that there is no public API or configuration settings to do so.
This affects GSS-API both with and without JAAS.
So where does this leave me?
i) Use Java GSS-API / GSS-API with JAAS “as is”, with each SGT Request hitting the KDC —> Not good.
ii) As suggested by Samson in the comments below, use Java GSS-API only for initial login of the application, then for all further calls use an alternative security mechanism for subsequent calls (a kind of self-built kerberos-light) using tokens or cookies.
iii) Consider alternatives to GSS-API such as Apache Kerby kerb-client. This has implications outside the scope of this answer, and may well prove to be jumping from the proverbial frying pan to the fire.
I have submitted a Java Feature Request to Oracle, suggesting that SGTs should be retrieved from the cache and stored in the Subject credentials (as already the case for TGTs).
http://bugs.java.com/bugdatabase/view_bug.do?bug_id=JDK-8180144
Question 2: Is there any downside to the fact that the service ticket is not saved to the cache?
Using the credentials cache for Service Tickets reduces interaction between the client and the KDC. The corollary to this is that where service tickets are not cached, each request will require interaction with the KDC, which could lead to the KDC being hammered.

How to obtain renewable kerberos tickets using java GSS+JAAS

I am using jTDS to connect to SQLServer. Internally jTDS uses GSS to obtain a kerberos' service ticket and establish a secure context. Since my app is long lived and my connections are kept alive the entire time I need that kerberos' service ticket to be renewable in order to allow SQL server to renew them on its own (the kdc policies are set to expire all tickets after 12 hours).
What jTDS does to obtain a kerberos token is (more or less) the following:
GSSManager manager = GSSManager.getInstance();
// Oids for Kerberos5
Oid mech = new Oid("1.2.840.113554.1.2.2");
Oid nameType = new Oid("1.2.840.113554.1.2.2.1");
// Canonicalize hostname to create SPN like MIT Kerberos does
GSSName serverName = manager.createName("MSSQLSvc/" + host + ":" + port, nameType);
GSSContext gssContext = manager.createContext(serverName, mech, null, GSSContext.DEFAULT_LIFETIME);
gssContext.requestMutualAuth(false);
gssContext.requestCredDeleg(true);
byte[] ticket = gssContext.initSecContext(new byte[0], 0, 0);
What I suspect is that the ticket I am obtaining is not renewable. I am checking that by doing something like the following:
ExtendedGSSContext extendedContext = (ExtendedGSSContext) gssContext;
boolean[] flags = (boolean[]) extendedContext.inquireSecContext(InquireType.KRB5_GET_TKT_FLAGS);
System.out.println("Renewable = " + flags[8]);
In our particular configuration GSS is getting kerberos TGT from JAAS login module. We have the following variable set to false -Djavax.security.auth.useSubjectCredsOnly=false and in the login.cfg file we have the following login module configured:
com.sun.security.jgss.krb5.initiate {
com.sun.security.auth.module.Krb5LoginModule required
useKeytTab=true
keyTab="/home/batman/.batman.ktab"
principal="batman#GOTHAMCITY.INT"
storeKey=true
doNotPrompt=true
debug=false
};
Another thing I notice is that the getLifetime() method of GSSContext doesn't seem to work. It always returns 2147483647 (max int) no matter what the real lifetime of the ticket is.
I feel confortable with branching jTDS driver, so I can modify the way it establishes a GSS context if needed.
What I tried:
Use native implementation of GSS api:
This works fine for me in terms of obtaining renewable tickets but it imposesses another set of issues (in terms of ensuring that the ticket cache is properly set and tickets in there are properly renew). If I can bypass this option it would be nice. Once thing I observe here is that the getLifetime() method actually returns the real lifetime in seconds of the ticket.
Reimplementing KerberosLoginModule:
Based on the answer to this question Jaas - Requesting Renewable Kerberos Tickets I reimplemented LoginModule to set the RENEW KDCOption in KrbAsReqBuilder before requesting a TGT. That works fine in the sense that I obtain a renewable TGT, but the ticket obtained from that TGT by GSS is still not renewable. If I set a breakpoint in the constructor of the KDCOption object and set the RENEW flag manually on each request (even the KrbTgsReq done by GSS) it works but making that change productive requires a major rewrite on GSS which I don't feel confortable with.

For administrators, the fact that Kerberos tickets have lifetime is an important security feature. User knows a password, so he/she may get a new ticket at any moment. But for intruder it's a problem - after the ticket expires, it can't be used to break into system. Administrators want this lifetime to be as short as possible, but not too short (like 1 hour) because users would generate like 10x more login requests than now, and it would be tough for ActiveDirectory to handle.
When we need to authenticate with Kerberos, we should use connection pooling (and DataSource). To use this feature in jTDS you need to add ConnectionPoolImplementation (recommended: DBCP or c3p0, see: http://jtds.sourceforge.net/features.html).
If you'd like to write your application using older way of connecting to database (without datasource, i.e. creating a connection and keeping it alive because it's expensive to create..) then the next obstacle would be 'renew lifetime'. In ActiveDirectory Kerberos tickets can be by default renewed within 7 days. There's a global setting in AD which allows to set there 0 (an indefinite renew lifetime), but you'd need to persuade Domain Administrator to lower security of whole domain just because one service wouldn't run without that.