[cabfpub] RFC5280

Jeremy Rowley jeremy.rowley at digicert.com
Wed Feb 24 18:56:24 UTC 2016

I've been playing around with Peter Bowen's certlint (an excellent tool)
and, looking at the cert universe as a whole, there are some noticeable
issues with the BRs and RFC 5280 that I though merited a public CAB Forum
discussion.  Some of this is likely me not knowing the entire history of
5280, so I appreciated any explanation. If there's exceptions we would like
to make to RFC5280, we should probably also push a bis with IETF at the same


Here's what I'm noticing are common issues:

1)      Org names, common names,  and address fields are limited to 64
characters. Very few international companies can comply with this
restriction. It's even worse if you are converting an IDN to a printable
string.  I don't think any browsers limit this to 64 characters?  Is there a
strong objection to permitting longer strings in these fields?

2)      keyAgreement isn't specifically prohibited in the BRs or 5280.
However, keyAgreement should no longer be used in ECC certs because of
security issues as explained by Ryan Sleevi in previous emails . We should
update the BRs to prohibit keyAgreement.

3)      Years ago, we discussed that 2047 bit certs were equivalent to 2048
bit certs (although the discussion may have occurred solely on the Mozilla
mailing list).  We should codify this exception. 

4)      Why is teletext string not permissible on a lot of these fields? I
also don't understand the weird requirement to use printablestring over
UTRF8 for some fields. Specifically, requiring a printable string for
subject:serialNumber could cause issues with the EV Guidelines if a country
uses an IDN as part of their registration number.  





-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.cabforum.org/pipermail/public/attachments/20160224/fd11e193/attachment-0002.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/pkcs7-signature
Size: 4964 bytes
Desc: not available
URL: <http://lists.cabforum.org/pipermail/public/attachments/20160224/fd11e193/attachment.p7s>

More information about the Public mailing list