diff mbox series

[v5,1/2] certs: Trigger creation of RSA module signing key if it's not an RSA key

Message ID 20210601105245.213767-2-stefanb@linux.ibm.com (mailing list archive)
State New
Headers show
Series Add support for ECDSA-signed kernel modules | expand

Commit Message

Stefan Berger June 1, 2021, 10:52 a.m. UTC
Address a kbuild issue where a developer created an ECDSA key for signing
kernel modules and then builds an older version of the kernel, when bi-
secting the kernel for example, that does not support ECDSA keys.

Trigger the creation of an RSA module signing key if it is not an RSA key.

Fixes: cfc411e7fff3 ("Move certificate handling to its own directory")
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Mimi Zohar <zohar@linux.ibm.com>
---
 certs/Makefile | 5 +++++
 1 file changed, 5 insertions(+)

Comments

Jarkko Sakkinen June 1, 2021, 5:58 p.m. UTC | #1
On Tue, Jun 01, 2021 at 06:52:44AM -0400, Stefan Berger wrote:
> Address a kbuild issue where a developer created an ECDSA key for signing
> kernel modules and then builds an older version of the kernel, when bi-
> secting the kernel for example, that does not support ECDSA keys.
> 
> Trigger the creation of an RSA module signing key if it is not an RSA key.
> 
> Fixes: cfc411e7fff3 ("Move certificate handling to its own directory")
> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
> Tested-by: Mimi Zohar <zohar@linux.ibm.com>

I've applied these to

git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd.git

Can revert too but do not mind taking care of these patches as they are
not intrusive in any possible way.

/Jarkko
diff mbox series

Patch

diff --git a/certs/Makefile b/certs/Makefile
index 359239a0ee9e..e6f97c64aa99 100644
--- a/certs/Makefile
+++ b/certs/Makefile
@@ -62,6 +62,11 @@  silent_redirect_openssl = 2>/dev/null
 # external private key, because 'make randconfig' might enable such a
 # boolean option and we unfortunately can't make it depend on !RANDCONFIG.
 ifeq ($(CONFIG_MODULE_SIG_KEY),"certs/signing_key.pem")
+
+X509TEXT=$(shell openssl x509 -in $(CONFIG_MODULE_SIG_KEY) -text)
+
+$(if $(findstring rsaEncryption,$(X509TEXT)),,$(shell rm -f $(CONFIG_MODULE_SIG_KEY)))
+
 $(obj)/signing_key.pem: $(obj)/x509.genkey
 	@$(kecho) "###"
 	@$(kecho) "### Now generating an X.509 key pair to be used for signing modules."