[PATCH 4/4] Documentation/admin-guide/module-signing.rst: add openssl command option example for CodeSign EKU

Lee, Chun-Yi
2021-01-20T09:14:06Z

Add an openssl command option example for generating CodeSign extended
key usage in X.509 when CONFIG_CHECK_CODESIGN_EKU is enabled.

Signed-off-by: "Lee, Chun-Yi" <jlee@suse.com>
---
Documentation/admin-guide/module-signing.rst | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/Documentation/admin-guide/module-signing.rst b/Documentation/admin-guide/module-signing.rst
index 7d7c7c8a545c..b57b30c7125f 100644
--- a/Documentation/admin-guide/module-signing.rst
+++ b/Documentation/admin-guide/module-signing.rst
@@ -170,6 +170,12 @@ generate the public/private key files::
-config x509.genkey -outform PEM -out kernel_key.pem \
-keyout kernel_key.pem

+When ``CONFIG_CHECK_CODESIGN_EKU`` option be enabled, the following openssl
+command option should be added for generating CodeSign extended key usage in
+X.509::
+
+ -addext "extendedKeyUsage=codeSigning"
+
The full pathname for the resulting kernel_key.pem file can then be specified
in the ``CONFIG_MODULE_SIG_KEY`` option, and the certificate and key therein will
be used instead of an autogenerated keypair.
--
2.16.4