Re: [exim] GnuTTS woes

Top Page
Delete this message
Reply to this message
Author: Evgeniy Berdnikov
Date:  
To: exim-users
Subject: Re: [exim] GnuTTS woes
On Thu, Sep 29, 2022 at 10:36:55AM +0200, Cyborg via Exim-users wrote:
> Am 28.09.22 um 17:51 schrieb Viktor Dukhovni via Exim-users:
> > I strongly disagree. There's no need to be a crypto
> > exhibitionist/maximalist. The vast majority of issuing CA RSA keys are
> > 2048-bits. The use of 4096-bit keys is pointless waste of CPU,
>
> There is a BSI ( the german cybersecurity agency ) guideline for german
> corps and gov entities, which states, that 2048 bit RSA keys, for any
> purpose,
> should not be used anymore in 2022.


https://www.bsi.bund.de/SharedDocs/Downloads/EN/BSI/Publications/TechGuidelines/TG02102/BSI-TR-02102-1.pdf?__blob=publicationFile&v=10

Comment to table 3.1:

| For a period of use beyond 2022, it is recommended to use RSA/DLIES
| keys of 3000 bits length to achieve a consistent level of security in
| all recommended asymmetric encryption schemes. The key length of 2000
| bits will remain compliant with this Technical Guideline for DLIES
| keys until the end of 2022, and also transitionally for RSA keys until
| the end of 2023.


So, BSI statement is significantly different from what you wrote.

> Can you state, why you think, that this 2048 bit key is only used for
> authentication, rather than for TLS encryption? I think, it is used, as it's
> presented on port 25.


You have better to study basics of TLS, really.
--
Eugene Berdnikov