Re: [TLS] matching identity, by default

[Stephen Farrell <[e-mail]>]

James Manger wrote:
> I strongly support the consistent identity check in the Security Considerations section of draft-ietf-tls-renegotiation-01.

Fair enough.

> There may be some niche uses of TLS for which changing an identity during renegotiation makes sense. That is adequately supported by the last paragraph in the Security Considerations: "A TLS library MAY provide a means for the application to allow identity and/or server_name changes across renegotiations...". However, for 99.9...% of TLS uses an identity changing during renegotiation will be totally unexpected by the higher-layer application and can only cause problems.

I'd buy that.

> A few people have argued that the consistent identity check is a separate issue that should not be addressed now. I don't think that is a fair characterisation. 

I'm not sure what you mean by "characterisation."

My point was simply that this *is* a different issue from the
renegotiation bug, that we're fixing that bug in "emergency"
mode and that we therefore shouldn't change *anything* else
whilst in that mode.

To give one example - rfc 2712 says how to use kerberos with
TLS. (I've no idea if that's really in use.) The text in -01
doesn't say how to handle that, but does have a MUST on
no-change. That could break something. I don't want to hold
the bug fix while we figure that out.

I just thinks its safer to do this later with some other draft
that UPDATEs 5246.

Stephen.