Java Security

Hi people,

I have tried the GSS-API without JAAS tutorial for java 1.5 at http://java.sun.com/j2se/1.5.0/docs/guide/security/jgss/tutorials/BasicClientServer.html with that config:

1) Environment config:
- JKD 1.5.0 update 11
- Windows XP pro against Active Directory on a Windows Server

2) The bcsLogin.conf jaas config file exactly as it appears in the tutorial

3) My krb5.conf file:

        [libdefaults]
                default_realm = MYCOMPANY.COM
                default_tkt_enctypes = rc4-hmac
                default_tgs_enctypes = rc4-hmac
        
        [realms]
                MYCOMPANY.COM = {
                        kdc = MYCOMPANY.COM
                        admin_server = MYCOMPANY.COM
                        default_domain = MYCOMPANY.COM
                }
        
        [domain_realm]
                MYCOMPANY = MYCOMPANY.COM

4) Parameters for the SampleServer program:
Program arguments
4444

VM arguments
-Djavax.security.auth.useSubjectCredsOnly=false
-Djava.security.krb5.conf=krb5.conf
-Djava.security.auth.login.config=bcsLogin.conf

5) Parameters for the SampleClient program:
Program arguments
krbtgt localhost 4444

VM arguments
-Djavax.security.auth.useSubjectCredsOnly=false
-Djava.security.krb5.conf=krb5.conf
-Djava.security.auth.login.config=bcsLogin.conf

After executing it I obtained the below checksum exception:

Checksum failed !
Exception in thread "main" java.lang.RuntimeException: GSSException: Failure unspecified at GSS-API level (Mechanism level: Checksum failed)
	at SampleServer.main(SampleServer.java:121)
Caused by: GSSException: Failure unspecified at GSS-API level (Mechanism level: Checksum failed)
	at sun.security.jgss.krb5.Krb5Context.acceptSecContext(Krb5Context.java:730)
	at sun.security.jgss.GSSContextImpl.acceptSecContext(GSSContextImpl.java:300)
	at sun.security.jgss.GSSContextImpl.acceptSecContext(GSSContextImpl.java:246)
	at SampleServer.main(SampleServer.java:118)
Caused by: KrbException: Checksum failed
	at sun.security.krb5.internal.crypto.ArcFourHmacEType.decrypt(ArcFourHmacEType.java:85)
	at sun.security.krb5.internal.crypto.ArcFourHmacEType.decrypt(ArcFourHmacEType.java:77)
	at sun.security.krb5.EncryptedData.decrypt(EncryptedData.java:167)
	at sun.security.krb5.KrbApReq.authenticate(KrbApReq.java:267)
	at sun.security.krb5.KrbApReq.<init>(KrbApReq.java:134)
	at sun.security.jgss.krb5.InitSecContextToken.<init>(InitSecContextToken.java:79)
	at sun.security.jgss.krb5.Krb5Context.acceptSecContext(Krb5Context.java:715)
	... 3 more
Caused by: java.security.GeneralSecurityException: Checksum failed
	at sun.security.krb5.internal.crypto.dk.ArcFourCrypto.decrypt(ArcFourCrypto.java:387)
	at sun.security.krb5.internal.crypto.ArcFourHmac.decrypt(ArcFourHmac.java:74)
	at sun.security.krb5.internal.crypto.ArcFourHmacEType.decrypt(ArcFourHmacEType.java:83)
	... 9 more

Apart from help for the exception itselft I have some questions:

1- For the SampleClient program I use krbtgt as the server name but I don�t know exactly why this works. Other values don�t work and I don�t know exactly what this server name is, who creates it, etc. I would be grateful for some explanation about it

2- I use the same username-password (mine) for authentication in the SampleServer and in the SampleClient, is that correct?

Thank you very much in advance.