Internet X.509 Public Key Infrastructure (PKI) Proxy Certificate Profile
draft-ietf-pkix-proxy-10
Yes
No Objection
Note: This ballot was opened for revision 10 and is now closed.
(Russ Housley; former steering group member) Yes
(Alex Zinin; former steering group member) No Objection
(Allison Mankin; former steering group member) No Objection
(Bert Wijnen; former steering group member) No Objection
(Bill Fenner; former steering group member) No Objection
(Harald Alvestrand; former steering group member) No Objection
(Jon Peterson; former steering group member) No Objection
(Margaret Cullen; former steering group member) No Objection
(Ned Freed; former steering group member) No Objection
Nits: Section 3.8.2 item 1) "The relying MUST party know how to" -> "The relying party MUST know how to" Section 3.8.2 item 3) a. Non-ASCII character appears where an apostrophe should be. Section 4.1.5 title "Proceedures" -> "Procedures" Appendix B should be marked as needing to be removed prior to publicaton. Questions: This document defines two policy language OIDs (basically "all" and "none"). Presumably more policy language OIDs will be defined. Does it make sense to have a registry for these things, or are these going to be so fine-grained attempting to register even some of them would be pointless? Is OCTET STRING necessarily the right data type for policy values? What if the policy language specifies policies using ASN.1? (I realize you can put arbitrary stuff inside an OCTET STRING, however, in X.400 P2 ASN.1 objects are stuffed inside of a P1 OCTET STRING field, and handling them in a single pass was a nightmare.) Some applications of these sorts of certificates seem to me to involve on-the-fly generation of new certificates. Additionally, each of these certificates is supposed to contain its own public/private key pair (2.6 item 3), and generating such key pairs can be expensive. Should the potential for service denial attacks on automatic proxy certificate generators be mentioned in the security considerations section?
(Steven Bellovin; former steering group member) (was Discuss) No Objection
(Ted Hardie; former steering group member) No Objection
This isn't a DISCUSS, but I was disturbed by the fact that section 2.7's advertising supplement on
ease of use contained this:
. For many users, properly managing their own EEC private key
is a nuisance at best, and a security risk at worst. One
option easily enabled with a PC is to manage the EEC private
keys and certificates in a centrally managed repository.
When a user needs a PKI credential, the user can login to the
repository using name/password, one time password, etc. Then
the repository can delegate a PC to the user with proxy
rights, but continue to protect the EEC private key in the
repository.
From my reading, this mechanism is way, way different from the motivation
given in section 2.3 and dear old Steve's file transfer. It seems in
particular to make this section of 2.4 problematic:
One concern that arises is what happens if a machine that has been
delegated the right to inherit Steve's privileges has been
compromised? For example, in the above scenario, what if the
machine running the file transfer service is compromised, such that
the attacker can gain access to the credential that Steve delegated
to that service? Can the attacker now do everything that Steve is
allowed to do?
The answer in the case of the attacker taking over the centrally managed
repository,seems to be a resounding "Yes!" I realize that this is not actually
quite the "delegated right to inherit" being discussed above, since that
scenario seems to have Steve getting the time-limited delegated right to his
own privileges, but it is still a bit worrying. The Security considerations
doesn't seem to cover this at all.
I don't think this has any great impact on the working of the protocol, but
I would personally suggest ripping the advertising supplement text there
right out or putting in the salient Security Consideration of "If you delegate
users proxy rights from a central managed repository of their own certificates,
boy are you in trouble if someone gets your repository". It may sound obvious,
but it probably needs to be said.
(Thomas Narten; former steering group member) No Objection