FULL PRODUCT VERSION :
java version "1.6.0_26"
Java(TM) SE Runtime Environment (build 1.6.0_26-b03)
Java HotSpot(TM) Client VM (build 20.1-b02, mixed mode, sharing)
ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows XP [Version 5.1.2600]
A DESCRIPTION OF THE PROBLEM :
Trying to invoke login with Krb5LoginModule, debug=false, doNotPrompt=true, useTicketCache=true, storeKey=false.
When an empty file krb5cc_<username> in <userhome> exists, this throws a NullPointerException in sun.security.krb5.Credentials.acquireDefaultCreds().
The cause is the following code:
if (cache == null) {
cache = CredentialsCache.getInstance();
}
if (cache != null) {
if (DEBUG) {
System.out.println(">>> KrbCreds found the default ticket " +
"granting ticket in credential cache.");
}
sun.security.krb5.internal.ccache.Credentials temp =
cache.getDefaultCreds();
if (EType.isSupported(temp.getEType())) {
result = temp.setKrbCreds();
} else {
if (DEBUG) {
System.out.println(
">>> unsupported key type found the default TGT: " +
temp.getEType());
}
}
}
where cache.getDefaultCreds() can and will return null in case the ticket cache is empty, so the EType.isSupported(...) fails.
REPRODUCIBILITY :
This bug can be reproduced always.