Jon Callas wrote:
On 11 May 2005, at 7:35 AM, David Shaw wrote:
On Tue, May 10, 2005 at 09:28:36PM -0700, "Hal Finney" wrote:
In my opinion, the critical bit on a notation packet should mean
that the implementation needs to recognize that particular notation,
not just notation packets in general. Otherwise we would have no way
of expressing the requirement that the particular notation packet be
understood.
That makes good sense, and I agree. However, the text in the draft
doesn't exactly say this (and rather implies the opposite).
I agree with Hal. I don't think that the text in the draft implies the
opposite, however. Here's a quote:
... The
purpose of the critical bit is to allow the signer to tell an
evaluator that it would prefer a new, unknown feature to generate an
error than be ignored.
This says to me that if you see a notation you don't understand, you
should error out.
Notations are our extension mechanism. It strikes me as perverse to
think that you only have to know the general concept of extensions and
not the specific extension.
I suggest adding this sentence (or similar) to the end of section
5.2.3.16. Notation Data:
When used on a notation subpacket, the critical bit refers to that
particular notation, and not to notation subpackets in general.
I put in:
If there is a critical notation, the criticality applies to that
specific
notation and not to notations in general.
but I'll bet you a beer someone finds a creative way to misinterpret this.
This whole discussion scares me. You have an extension mechanism with no
registry for extensions.
When these things get popular, it turns out everyone hates them. cf. DNS
TXT records.
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