code review request: 7077646: gssapi wrap for CFX per-message tokens always set FLAG_ACCEPTOR_SUBKEY

Weijun Wang weijun.wang at oracle.com
Thu Sep 22 08:05:31 PDT 2011


Webrev at

   http://cr.openjdk.java.net/~weijun/7077646/webrev.00/

According to RFC 4121 [1]:

   2.  Key Derivation for Per-Message Tokens

   ...

    During the context initiation and acceptance sequence, the acceptor
    MAY assert a subkey in the AP-REP message.  If the acceptor asserts a
    subkey, the base key is the acceptor-asserted subkey and subsequent
    per-message tokens MUST be flagged with "AcceptorSubkey", as
    described in section 4.2.2.  Otherwise, if the initiator asserts a
    subkey in the AP-REQ message, the base key is this subkey;  if the
    initiator does not assert a subkey, the base key is the session key
    in the service ticket.

Java has not checked where the key comes from and always sets the 
AcceptorSubkey on. This has worked well with the MIT impl because it 
seems the MIT impl only checks the flag if it should be on but doesn't 
when it should be off. However, Heimdal is more strict and check in both 
cases and an interop error happens between Java and Heimdal.

In the customer's case, the Apple iChat program uses Heimdal's krb5 impl 
and cannot communicate well with the Openfire Java jabber server.

I would like >= 2 reviewers so it can be backported to a 7u release. I'm 
still working on a 6u solution at the moment.

Thanks
Max

[1]

-------- Original Message --------
*Change Request ID*: 7077646

*Synopsis*: gssapi wrap for CFX per-message tokens always set 
FLAG_ACCEPTOR_SUBKEY

   Product: java
   Category: jgss
   Subcategory: krb5plugin

=== *Description* 
============================================================
FULL PRODUCT VERSION :


A DESCRIPTION OF THE PROBLEM :
gssapi wrap for CFX per-message tokens always set FLAG_ACCEPTOR_SUBKEY 
even though the acceptor doesn't send a sub key.



STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
attach debugger to client and see that the the acceptor doesn't send a 
subkey in the authenticator, see what it sent FLAG_ACCEPTOR_SUBKEY in 
all per-message tokens.



EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
send subkey or don't set flag.

REPRODUCIBILITY :
This bug can be reproduced always.




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