Thanks, Ben; this helps a lot. Jim, are you good with Ben's suggestion or a variation of that? It's just a small update to what you have, and makes it clearer that if you need I18N, PRECIS is the weay to do it.
Barry On Fri, Feb 21, 2020 at 10:08 PM Benjamin Kaduk <[email protected]> wrote: > > Hi Barry, > > On Sat, Feb 15, 2020 at 12:12:29AM -0500, Barry Leiba wrote: > > Hi, all... > > > > I'm sorry if I'm not completely clear about where the discussion is, > > but what Jim's mail system does to the quoting is horrendous (as is > > the case with most HTML-based mail systems), and I can't easily follow > > the thread. > > I sympathize; I find that with some regularity I end up saving the > text/html component to a file and opening it in a browser in order to have > a chance of figuring out what's going on. > > > So I'm just picking up this recent bit from Ben: > > > > > I think it would probably be helpful for the responsible AD to chime in; > > > my > > > understanding is still that the PRECIS profiles are to be used as part of > > > a > > > protocol as opposed to part of a deployment, and that allowing for > > > different rules to be used in different sites is risky. I understand that > > > there's the extra context here of the potential for preexisting > > > deployments > > > that started using non-ASCII passwords in the absence of any guidance from > > > the IETF on how to do so, and we have to consider whether what we do will > > > break them, and so hearing from someone versed in the matter who has > > > thought about this particular case would help assuage my concerns. One > > > possible route (given that, as I understand it, a lot of EPP deployments > > > involve exchange of configuration and deployment information between peers > > > out of band) would be to say that the PRECIS profile is used as a default > > > in the absence of other configuration knowledge for a given deployment, > > > though I acknowledge that this is not without flaws. > > > > I had discussed the PRECIS issue with Jim, which is what resulted in this > > text: > > > > It is recommended that the plain text password in the <loginSec:pw> > > and <loginSec:newPw> elements use printable ASCII characters #x20 > > (space) - #x7E (~), with high entropy, such as 128 bits. If non- > > ASCII characters are supported with the plain text password, then use > > a standard for passwords with international characters, such as the > > OpaqueString PRECIS profile in [RFC8265]. > > > > I think that's adequate, given that (1) we really are expecting that > > almost all passwords out there are ASCII, and we're recommending > > keeping it that way, (2) we need to allow, but discourage, non-ASCII > > UTF-8 passwords for the (expectedly rare) cases where they might be > > used, and (3) these are stored passwords that are passed around, > > rather than passwords entered by users and subject to issues created > > by different input mechanisms and effects on eyeballs. > > > > I can see that we might want to change "recommended" to "RECOMMENDED", > > and I don't object to that (Jim?). Beyond that, I'm not sure where > > you're going with "PRECIS profiles are to be used as part of a > > protocol as opposed to part of a deployment." It's really both, > > depending upon the situation. In this case, it's saying that if your > > server supports non-ASCII passwords, you'd better use the OpaqueString > > profile to handle them. If your server doesn't (it supports only > > I'm much happier with your prose description here than the snippet quoted > from the document -- what's in the document now seems to be weaker than > what you say ("pick a standard; PRECIS is a standard" vs "you should use > PRECIS, though here's an out if you can't for some reason"). > > My primary concern here is that the client and server need to know to use > the same standard (whatever it is). Making this RFC say flatly "use > PRECIS" is IMO the easiest way to do that, though given how much other > stuff in EPP has to be set by out-of-band configuration I won't raise a > fuss if this ends up being another one. If it does need to be known out of > band, though, my preference is always for that need to be stated in the > RFC. > > > ASCII passwords), we're good. From a PRECIS point of view, I don't > > see more that needs to be done with this. > > > > I think a large part of the point of the text that Jim added is an > > acknowledgement that in the common case of ASCII-only passwords, we > > don't have to worry about normalization/canonicalization of password > > strings at all, and just doing straight byte-string comparisons works. > > And the OpaqueString profile is there for cases where it's needed. > > > > Now, it's certainly true that if a server *supports* non-ASCII > > passwords, then *all* password processing on that server has to use > > the OpaqueString profile, even if there are not any actual non-ASCII > > passwords present... just in case one might show up. And I think the > > text does say that. > > (repeating myself, but I think the text says "all password processing on > that server has to use the chosen standard for non-ASCII passwords" [which > is not necessarily the OpaqueString PRECIS profile]) > > > Is there something in this discussion that I'm missing that I need to > > address? Is there specific text you might suggest? Are there other > > issues beyond this one that are still open? How close are we to > > resolving this? > > I think just adding the extra background and your sense of what the text is > trying to convey has been a big help. I would suggest rewording to: > > [...]. If non- > ASCII characters are supported with the plain text password, then use > a standard for passwords with international characters; the > OpaqueString PRECIS profile in [RFC8265] is recommended in the absence of > other considerations. > > Your explanation suffices such that I will not require this change to clear > my Discuss, though. > > -Ben _______________________________________________ regext mailing list [email protected] https://www.ietf.org/mailman/listinfo/regext
