lkml.org 
[lkml]   [2022]   [Jan]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC][PATCH v3a 00/11] ima: support fs-verity digests and signatures (alternative)
On Thu, Jan 27, 2022 at 07:46:09PM +0100, Roberto Sassu wrote:
> I wanted to propose a different approach for handling fsverity digests and
> signatures, compared to:
>
> https://lore.kernel.org/linux-integrity/20220126000658.138345-1-zohar@linux.ibm.com/
>
> In the original proposal, a new signature version has been introduced (v3)
> to allow the possibility of signing the digest of a more flexible data
> structure, ima_file_id, which could also include the fsverity file digest.
>
> While the new signature type would be sufficient to handle fsverity file
> digests, the problem is that its format would not be compatible with the
> signature format supported by the built-in verification module in fsverity.
> The rpm package manager already has an extension to include fsverity
> signatures, with the existing format, in the RPM header.
>
> Given that the fsverity signature is in the PKCS#7 format, IMA has already
> the capability of handling it with the existing code, more specifically the
> modsig code. It would be sufficient to provide to modsig the correct data
> to avoid introducing a new signature format.

I think it would be best to get people moved off of the fs-verity built-in
signatures, rather than further extend the use of it. PKCS#7 is a pretty
terrible signature format. The IMA one is better, though it's unfortunate that
IMA still relies on X.509 for keys.

- Eric

\
 
 \ /
  Last update: 2022-01-27 20:36    [W:0.149 / U:0.368 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site