2007/670 db_credp update

[James Carlson]

Erik Nordmark writes:
> James Carlson wrote:
> 
> > The behavior of msg_extractcred seems a little unclear.  Is it
> > possible for an mblk_t b_cont chain to have two or more mblk_t entries
> > with non-NULL db_credp?  If so, then extracting can have the strange
> > side-effect of uncovering old creds unless the function continues
> > through the rest of the b_cont chain, clearing out and discarding any
> > creds it finds.
> 
> That isn't the use case for msg_extractcred().
> The use case if the need to efficiently move a cred/cpid from one 
> message (e.g., a TCP/IP packet with a SYN) to another message (e.g., a 
> T_CONN_IND) and then discard the original message.

OK.  It sounds like that usage pattern is part of the interface
definition.

> > Version number? 
> 
> Yes, the ARC review process encourages folks to think about versioning 
> their interfaces ;-)

Indeed.  Though just adding a version number usually doesn't do the
trick, and is often meaningless if there's only one consumer in the
same consolidation.  :-/

>  >  Are there users of this interface outside of ON?
> 
> There are no contracted users of this interface.
> 
> However, we know that one customer which has a kernel protocol stack on 
> top of SCTP has been told about this interface (including its lack of 
> stability) and we are working with them to have them be able to easily 
> move to the new version of the interface.

OK; that's a good reason.  Thanks ...

-- 
James Carlson, Solaris Networking              <james.d.carlson at sun.com>
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