CA/Required or Recommended Practices

CA Recommended Practices

This page contains a draft set of recommended practices for CAs wishing to have their root CA certificates included in Mozilla products. In some cases these practices are specified or implied by the Mozilla CA certificate policy, and are mandatory for a CA to have its root certificate(s) included. In other cases the recommended practices are not mandatory per policy, but will help speed up a CA's application for inclusion and maximize the chances of its application being approved.

Recommended practices

• CAs should supply the complete Certification Policy (CP) and Certification Practice Statement (CPS) containing sufficient information to determine whether and how the CA complies with the Mozilla policy requirements.
  • The CP/CPS should be publicly available from the CA's official web site.
  • The format of the CP/CPS document should be PDF or another suitable format for reading documents. CAs should not use Microsoft Word or other formats intended primarily for editable documents.
  • The CP/CPS should be available in an English version.

• CAs should supply evidence of their being evaluated according to one or more of the criteria accepted as suitable per the Mozilla policy.
  • All documents supplied as evidence should be publicly available.
  • Documents purporting to be from the CA's auditor (or other evaluator) should be available directly from the auditor (e.g., as documents downloadable from the auditor's web site.)

• CAs should indeed address the issue of homographic spoofing of internationalized domain names (IDNs) in their CP/CPS, even if primary responsibility for this falls on domain registries. This doesn't mean that the CAs prevent such spoofing. It merely means that a CA describes how it handles the issue of spoofing when authenticating the owner of a domain.

Notes for future work

• What (if anything) should we do regarding the use of non US-ASCII character sets in certs? To what extent is this supported today in NSS and by CAs? This whole problem seems analogous to the IDN problem.
  • Excluding the IDN problem (on which I comment under "Recommended practices"), care should be taken to avoid setting technical requirements more stringent than the X.509 specifications. If X.509 permits non-US-ASCII characters in certificates and if NSS and the Mozilla products that use it can operate correctly in the presence of such characters, they should be permitted. On the other hand, if non-US-ASCII characters cause technical problems for NSS or the Mozilla products that use it, that is already addressed under item #4 (after the first two bullets) in the existing policy. Of course, it might be appropriate to add a new bullet in the second set of bullets under item #4 to state explicitly that certificates must not contain any characters that cause software failures or security vulnerabilities in Mozilla products.