I have the following
- spring web application on JBoss EAP 7.2.2 - Machine CentOs
- Keycloak 3.3.4 on CentOs
- Active directory
We run on OpenJDK 8
Users login from Windows machines using their Active directory accounts.
Keycloak is configured with a kerberos use federation. On CentOs machines a kerberos client is installed using
yum install krb5-user krb5-doc
yum install krb5-pkinit krb5-workstation
yum install krb5-libs krb5-devel
yum install krb5-server krb5-workstation pam_krb5
In keycloak user federation, the keytab file path an other configrations are correct. This is confirmed by the keycloak log file. Realm: XYZ.COM Server principal HTTP/principal-name@REALM
Keytab file is generated using
ktpass.exe /out file.keytab /mapuser user-name@REALM /mapop set /princ HTTP/principal-name@REALM /ptype KRB5_NT_PRINCIPAL /pass XXXXXX /crypto RC4-HMAC-NT
in krb5.conf the following is entered
default_tgs_enctypes = arcfour-hmac
default_tkt_enctypes = arcfour-hmac
permitted_enctypes = arcfour-hmac
Problem is while login we get the exception
Looking for keys for: HTTP/principal-name@REALM
2020-02-24 09:34:06,327 WARN [org.keycloak.federation.kerberos.impl.SPNEGOAuthenticator] (default task-13) SPNEGO login failed: java.security.PrivilegedActionException: GSSException: Failure unspecified at GSS-API level (Mechanism level: Invalid argument (400) - Cannot find key of appropriate type to decrypt AP REP - RC4 with HMAC)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.keycloak.federation.kerberos.impl.SPNEGOAuthenticator.authenticate(SPNEGOAuthenticator.java:68)
at org.keycloak.storage.ldap.LDAPStorageProvider.authenticate(LDAPStorageProvider.java:677)
at org.keycloak.credential.UserCredentialStoreManager.authenticate(UserCredentialStoreManager.java:296)
at org.keycloak.authentication.authenticators.browser.SpnegoAuthenticator.authenticate(SpnegoAuthenticator.java:89)
at org.keycloak.authentication.DefaultAuthenticationFlow.processFlow(DefaultAuthenticationFlow.java:200)
at org.keycloak.authentication.AuthenticationProcessor.authenticateOnly(AuthenticationProcessor.java:853)
at org.keycloak.authentication.AuthenticationProcessor.authenticate(AuthenticationProcessor.java:722)
at org.keycloak.protocol.AuthorizationEndpointBase.handleBrowserAuthenticationRequest(AuthorizationEndpointBase.java:145)
at ...
Caused by: GSSException: Failure unspecified at GSS-API level (Mechanism level: Invalid argument (400) - Cannot find key of appropriate type to decrypt AP REP - RC4 with HMAC)
at sun.security.jgss.krb5.Krb5Context.acceptSecContext(Krb5Context.java:856)
at sun.security.jgss.GSSContextImpl.acceptSecContext(GSSContextImpl.java:342)
at sun.security.jgss.GSSContextImpl.acceptSecContext(GSSContextImpl.java:285)
at sun.security.jgss.spnego.SpNegoContext.GSS_acceptSecContext(SpNegoContext.java:906)
at sun.security.jgss.spnego.SpNegoContext.acceptSecContext(SpNegoContext.java:556)
at sun.security.jgss.GSSContextImpl.acceptSecContext(GSSContextImpl.java:342)
at sun.security.jgss.GSSContextImpl.acceptSecContext(GSSContextImpl.java:285)
at org.keycloak.federation.kerberos.impl.SPNEGOAuthenticator.establishContext(SPNEGOAuthenticator.java:169)
at org.keycloak.federation.kerberos.impl.SPNEGOAuthenticator$AcceptSecContext.run(SPNEGOAuthenticator.java:132)
at org.keycloak.federation.kerberos.impl.SPNEGOAuthenticator$AcceptSecContext.run(SPNEGOAuthenticator.java:122)
... 72 more
Caused by: KrbException: Invalid argument (400) - Cannot find key of appropriate type to decrypt AP REP - RC4 with HMAC
at sun.security.krb5.KrbApReq.authenticate(KrbApReq.java:278)
at sun.security.krb5.KrbApReq.<init>(KrbApReq.java:149)
at sun.security.jgss.krb5.InitSecContextToken.<init>(InitSecContextToken.java:108)
at sun.security.jgss.krb5.Krb5Context.acceptSecContext(Krb5Context.java:829)
... 81 more
2020-02-24 09:34:06,328 INFO [stdout] (default task-13) [Krb5LoginModule]: Entering logout
2020-02-24 09:34:06,328 INFO [stdout] (default task-13) [Krb5LoginModule]: logged out Subject
I already made a lot of research and unforunately excluded all possible reasons. The following tests were done: klist -k {path to keytab file} -e
Result 4 HTTP/principal-name@REALM arcfour-hmac In Active directory the msDS-KeyVersionNumber = 4
kinit HTTP/principal-name@REALM klist -e
Result: ... Etype (skey, TKT) arcfour-hmac, aes256-cts-hmac-sha1-96
In summary Keycloak is able to read the keytab, but it fails to lookup a decryption key.
Anyone can help?
I already viewed this post Kerberos - Cannot find key of appropriate type to decrypt AP REP - RC4 with HMAC
And the following link: https://bugs.openjdk.java.net/browse/JDK-8193855
and many other posts, but no success.