Well, it depends. There are some software vendors that “request” to have the 
TSA signed by a known certificate, and as they only trust on root certificate, 
usually to get your timestamps “recognized” you have to sign the TSA with the 
CA root cert just in case.

 

De: [email protected] [mailto:[email protected]] En nombre 
de Dimitris Zacharopoulos
Enviado el: jueves, 8 de septiembre de 2016 16:39
Para: Bruce Morton
CC: [email protected]
Asunto: Re: [cabfpub] Questions regarding timestamping certificates

 

 

On 8/9/2016 4:59 μμ, Bruce Morton wrote:

Hi Dimitris,

 

I don’t think that the spirit of BR 6.1.7 would be for a root CA to issue a 
certificate for a TSA. Also, the members of the Code Signing Working Group have 
recommended that there be a separate CA for issuing time-stamping certificates 
which is defined in Appendix B (4) of the Minimum Requirements for Code Signing 
certificates.

 


That was my initial reading too and thank you for confirming. If others think 
that's not the case, please let us know.




You may want to get feedback directly from the vendor of the client software 
which will validate the time-stamp signatures.

 


I don't think that will  be necessary because if the standards require a 2 
level certificate chain verification, the client software must support it :)


Best regards,
Dimitris.




Bruce.

 

From: Dimitris Zacharopoulos [mailto:[email protected]] 
Sent: Thursday, September 8, 2016 9:03 AM
To: Bruce Morton  <mailto:[email protected]> <[email protected]>; 
[email protected]
Subject: Re: [cabfpub] Questions regarding timestamping certificates

 

On 8/9/2016 3:07 μμ, Bruce Morton wrote:

Hi Dimitris,

 

I think the best document to use for Time-stamping Authority is the Minimum 
Requirements for Code Signing certificates, see 
https://casecurity.org/wp-content/uploads/2016/07/Minimum-requirements-for-the-Issuance-and-Management-of-code-signing.pdf.

 

Thanks, Bruce.


Thank you Bruce, you helped me find answers related to my second question. I am 
not 100% sure if it answers my first question. The minimum requirements for 
code signing document, describes a scenario where there are explicit 
Subordinate CA Certificates for TimeStamping but there is no requirement that 
forbids end-entity certificates to be issued directly from the Root (at least 
not one I could spot straight away). 

I guess my 1st question is more focused on what is allowed under the currently 
approved CA/B Forum Baseline Requirements.


Best regards,
Dimitris.






 

From: [email protected] [mailto:[email protected]] On 
Behalf Of Dimitris Zacharopoulos
Sent: Thursday, September 8, 2016 4:34 AM
To: [email protected]
Subject: [cabfpub] Questions regarding timestamping certificates

 

Hello everyone,

We are setting up a new Timestamping Authority and we are looking for specific 
rules that apply to certificates and subCA Certificates related to 
timestamping. While reading various standards and the CA/B Forum documents, and 
after looking at various existing implementations of publicly-trusted CAs, I 
have some questions and would appreciate any feedback from the forum. Although 
the BRs apply to SSL certificates, some Root Certificates might be used for 
both SSL and timestamping services. So the questions that follow, apply to CAs 
that use the same Root Certificate for both SSL and timestamping purposes. Of 
course, the EV CodeSigning requirements also define some rules for "EV 
Timestamp Authorities".

1.      Section 6.1.7 of the Baseline Requirements states that the Root CA 
Private Keys MUST NOT be used to sign end-entity certificates with some 
exceptions. This exception list does not specifically mention end-entity 
certificates with EKU id-kp-timeStamping. Are Root CAs allowed to directly 
issue end-entity certificates for timestamping authorities (end-entity 
certificates with EKU only id-kp-timeStamping)?
2.      Section 4.9.7 describes the CRL issuance frequency for Subscriber and 
Subordinate CA Certificates. If there is a Subordinate CA Certificate 
constrained with EKU id-kp-timeStamping, is an end-entity certificate (with 
only id-kp-timeStamping) issued from that subCA considered a "Subscriber" 
Certificate? Should this subCA issue CRLs every 7 days or every 12 months? My 
understanding (according to section 1.1 of the BRs) is that the end-entity 
certificates from that subCA are not required to comply with the CA/B Forum 
BRs. This should allow the CA to choose the CRL issuance (from that restricted 
subCA), to exceed the 7-day requirement.


Thank you in advance.


Dimitris Zacharopoulos.






 

 

Attachment: smime.p7s
Description: S/MIME cryptographic signature

_______________________________________________
Public mailing list
[email protected]
https://cabforum.org/mailman/listinfo/public

Reply via email to