Subject: [dane] Draft -18

From: Paul Hoffman <[email-masked]>
Date: Fri, 9 Mar 2012 09:49:44 -0800

... has everything Jakob and I believe we were instructed to do by the chairs. The chairs will also decide what to do about the issue under discussion with the definition of usage type 2, but we wanted to get everyone a clean draft to look at.

--Paul Hoffman

---

From: Leif Johansson <[email-masked]>
Date: Mon, 12 Mar 2012 16:38:45 +0100

On 03/09/2012 06:49 PM, Paul Hoffman wrote:
> ... has everything Jakob and I believe we were instructed to do by
> the chairs. The chairs will also decide what to do about the issue
> under discussion with the definition of usage type 2, but we wanted
> to get everyone a clean draft to look at.
> 

I've reviewed -18. I find it good enough to publish.

Let us please ship this version and move on to other stuff!

	Cheers Leif

---

From: Peter Sylvester <[email-masked]>
Date: Mon, 12 Mar 2012 17:41:44 +0100

I have some comments on the wording of the introdcuctory sections:

The abstract

    Encrypted communication on the Internet often uses Transport Level
    Security (TLS), which depends on third parties to certify the keys
    used.  This document improves on that situation by enabling the
    administrator of a domain name to certify the keys used in that
    domain's TLS servers.  This requires matching improvements in TLS
    client software, but no change in TLS server software.

- There are other methods than certified public keys that can be used for
   mutual authentication combined with encryption key establishment.

Wouldn't it be more correct to replace the first sentence in the 
abstract by something like

"Encrypted communication on the Internet often uses Transport Level 
Security (TLS).
Authentication in TLS, when based on certified public keys, often 
depends on third parties."

The second: "Improving a situation"  may sound like a judgement? Isn't 
it sufficient to
state something like:

"This document describes a method that enables an administrator of a 
domain name to certify
the keys used in that domain's TLS servers."

In the background between the two paragraphs

    The security properties of encryption systems depend strongly on the
    keys that they use.  If secret keys are revealed, or if published
    keys can be replaced by bogus keys, these systems provide little or
    no security.

    TLS uses certificates to bind keys and names.

there seems to be a gap?

- Nothing is says why binding keys and names is related to publishing keys
   or whatever.

- The paragraph before talks about encryption keys, in TLS the ones used
   for data encryption are not the ones that are certified.

See proposal for the abstract and add something like:

   In order to establish a shared encryption key for data exchanges, TLS
   may use various methods, one consists of transporting such keys to
   the intended partner using encryption with public keys. This method
   requires that the public key is securely associated with some identity
   or name of the intended partner.

   TLS uses public key certificates ...

In the sentence

    CCAs protect their secret
    key vigorously, while supplying their public key to the software
    vendors who build TLS clients.

the first part could be removed I think and the second is not
complete. They provide there root keys to anyone who wants them I guess.
And they also supply their name. For convenience, the binding of a name
  is provided in general as a self signed certificate.

    TLS client software uses a set of these CA keys as "trust anchors"

and the associated names.

   This solution has gradually broken down because some CAs have become
    untrustworthy.

Untrustworthy for doing what? "to establish correct associations
of names and keys."

1.2:

    A TLS client begins a connection by exchanging messages with a TLS
    server.  It looks up the server's name using the DNS to get Internet
    Protocol (IP) address associated with the name.

A client established a connection using an IP address.
This IP address may have been obtained by using a DNS to
resolve a name of the server. Well...

The first response from the server in TLS may contain a certificate.

Good. see above my remarks.

Currently, the client must extract the domain name from the
    certificate

The client must match the server name against the identities
present in the certificat.

regards
Peter Sylvester

---

From: "Murray S. Kucherawy" <[email-masked]>
Date: Thu, 29 Mar 2012 15:06:37 +0000

> -----Original Message-----
> From: [email-masked] [mailto:[email-masked]] On Behalf Of Paul Hoffman
> Sent: Friday, March 09, 2012 9:50 AM
> To: IETF DANE WG list
> Subject: [dane] Draft -18
> 
> ... has everything Jakob and I believe we were instructed to do by the
> chairs. The chairs will also decide what to do about the issue under
> discussion with the definition of usage type 2, but we wanted to get
> everyone a clean draft to look at.

Hi Paul and everyone,

Just checking in: I've been assigned the AppsDir review for this draft, which is good because I've been meaning to track the work more closely anyway.  (In fact, I volunteered to do it.)

I was hoping to get it done on my way here, but it didn't happen.  I plan to do it on the flights home, so I hope to have it to you within a week or so.

-MSK