From: Dimitri John Ledkov <dimitri.ledkov@canonical.com>
To: David Howells <dhowells@redhat.com>,
David Woodhouse <dwmw2@infradead.org>
Cc: linux-modules@vger.kernel.org, linux-crypto@vger.kernel.org,
herbert@gondor.apana.org.au, mcgrof@kernel.org,
keyrings@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] crypto: Limit MODULE_SIG_KEY_TYPE_ECDSA to SHA384 or SHA512
Date: Tue, 10 Oct 2023 22:27:55 +0100 [thread overview]
Message-ID: <20231010212755.64744-1-dimitri.ledkov@canonical.com> (raw)
NIST FIPS 186-5 states that it is recommended that the security
strength associated with the bit length of n and the security strength
of the hash function be the same, or higher upon agreement. Given NIST
P384 curve is used, force using either SHA384 or SHA512.
Signed-off-by: Dimitri John Ledkov <dimitri.ledkov@canonical.com>
---
certs/Kconfig | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/certs/Kconfig b/certs/Kconfig
index 1f109b0708..84582de66b 100644
--- a/certs/Kconfig
+++ b/certs/Kconfig
@@ -30,9 +30,11 @@ config MODULE_SIG_KEY_TYPE_RSA
config MODULE_SIG_KEY_TYPE_ECDSA
bool "ECDSA"
select CRYPTO_ECDSA
+ depends on MODULE_SIG_SHA384 || MODULE_SIG_SHA512
help
- Use an elliptic curve key (NIST P384) for module signing. Consider
- using a strong hash like sha256 or sha384 for hashing modules.
+ Use an elliptic curve key (NIST P384) for module signing. Use
+ a strong hash of same or higher bit length, i.e. sha384 or
+ sha512 for hashing modules.
Note: Remove all ECDSA signing keys, e.g. certs/signing_key.pem,
when falling back to building Linux 5.14 and older kernels.
--
2.34.1
next reply other threads:[~2023-10-10 21:28 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-10-10 21:27 Dimitri John Ledkov [this message]
2023-10-10 22:38 ` [PATCH] crypto: Limit MODULE_SIG_KEY_TYPE_ECDSA to SHA384 or SHA512 Luis Chamberlain
2023-10-20 5:54 ` Herbert Xu
2023-10-20 5:56 ` Herbert Xu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20231010212755.64744-1-dimitri.ledkov@canonical.com \
--to=dimitri.ledkov@canonical.com \
--cc=dhowells@redhat.com \
--cc=dwmw2@infradead.org \
--cc=herbert@gondor.apana.org.au \
--cc=keyrings@vger.kernel.org \
--cc=linux-crypto@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-modules@vger.kernel.org \
--cc=mcgrof@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).