Thanks for your comments, Andrey!
On 03/17/2010 08:02 AM, Andrey Ivanov wrote:
Hi Noriko,
i've read the design document http://directory.fedoraproject.org/wiki/Upgrade_to_New_DN_Format
In order to support "Old DN format including DN in the double quotes"
another cn=config switch may be necessary. It seems there was recently
a new switch introduced to make the dn syntax validation a little more
"relaxed" - nsslapd-dn-validate-strict. Maybe this one could be used to
allow for DNs with double-quoted values?
Actually, the way how we are going to handle the old style 'dn:
<type>="<nested dn>",<the rest>' is converting the
old style to a new style in the normalization when the server receives
DNs from clients and the converted new style DN is used in the rest of
the process. The nsslapd-dn-validate-strict value is examined in the
DN syntax validation code for now. Unless we change it, the DN syntax
validation code always receives the new DN style.
That being said, are you suggesting if nsslapd-dn-validate-strict is
on, we should not convert an old style DN to a new style? That'd be
really strict. I'm leaning toward to the other side accepting the both
old and new style with no restriction. Do you see any disadvantages in
allowing the old style?
Here is the commit comment for that parameter :
commit 0410819d48795fca4faf986cf8658c34c4d929e3
Author: Nathan Kinder <nkinder@redhat.com>
Date: Wed May 13 11:12:11 2009 -0700
Add strict DN syntax enforcement option.
The DN syntax has become more restrictive over time, and the
current rules are quite strict. Strict adherence to the rules
defined in RFC 4514, section 3, would likely cause some pain to
client applications. Things such as spaces between the RDN
components are not allowed, yet many people use them still since
they were allowed in the previous specification outlined in RFC
1779.
To deal with the special circumstances around validation of the DN
syntax, a configuration attribute is provided named
nsslapd-dn-validate-strict. This configuration attribute will
ensure that the value strictly adheres to the rules defined in RFC
4514, section 3 if it is set to on. If it is set to off, the server
will normalize the value before checking it for syntax violations.
Our current normalization function was designed to handle DN values
adhering to RFC 1779 or RFC 2253
Concerning the logic of escaping/unescaping/normalisation we could test
how openldap behaves in each case (as you've made it in "DN HEX HEX"
bug).
Yes, I did. :) I found they are correctly handling the cases including
escaped characters and non-ASCII UTF-8 characters in the seamless
manner.
For upgrades/migrations and double quotes in DNs: the two values may be
left during the upgrade (just in case someone uses them as-is) and then
an optional validation/cleaning script could be provided separately?
All right. That should work. I'm adding the validation/cleaning
script to the design memo.
The sensitive part here is the whole o-NetscapeRoot tree:
console using and writing this type of values, replication
agreement/management etc
Indeed.
As for the "related bugs" section i think another bug should be added (https://bugzilla.redhat.com/show_bug.cgi?id=199923),
it concernes the same RFC4514 compliance.
Oops. That's right. I'm adding it, too.
Thanks so much for your comments.
--noriko