[PATCH 2/5] keys: generate self-signed module signing key using CSR

[Jarkko Sakkinen]

On Thu, Feb 11, 2021 at 02:54:32PM -0500, Nayna Jain wrote:
> Loading a key on the IMA trusted keyring requires the key be signed
> by an existing key on the builtin or secondary trusted keyring.
> Creating a Certificate Signing Request (CSR) allows the certificate
> to be self-signed or signed by a CA.
> 
> This patch generates a self-signed module signing key using CSR.

"Generate ..."

/Jarkko

> 
> Signed-off-by: Nayna Jain <nayna at linux.ibm.com>
> ---
>  Makefile       |  3 ++-
>  certs/Makefile | 15 +++++++++++----
>  2 files changed, 13 insertions(+), 5 deletions(-)
> 
> diff --git a/Makefile b/Makefile
> index af18aab6bbee..9c87fdd600d8 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -1473,7 +1473,8 @@ MRPROPER_FILES += include/config include/generated          \
>  		  .config .config.old .version \
>  		  Module.symvers \
>  		  certs/signing_key.pem certs/signing_key.x509 \
> -		  certs/x509.genkey \
> +		  certs/x509.genkey certs/signing_key.key \
> +		  certs/signing_key.crt certs/signing_key.csr \
>  		  vmlinux-gdb.py \
>  		  *.spec
>  
> diff --git a/certs/Makefile b/certs/Makefile
> index f4c25b67aad9..b2be7eb413d3 100644
> --- a/certs/Makefile
> +++ b/certs/Makefile
> @@ -60,11 +60,18 @@ $(obj)/signing_key.pem: $(obj)/x509.genkey
>  	@$(kecho) "### needs to be run as root, and uses a hardware random"
>  	@$(kecho) "### number generator if one is available."
>  	@$(kecho) "###"
> -	$(Q)openssl req -new -nodes -utf8 -$(CONFIG_MODULE_SIG_HASH) -days 36500 \
> -		-batch -x509 -config $(obj)/x509.genkey \
> -		-outform PEM -out $(obj)/signing_key.pem \
> -		-keyout $(obj)/signing_key.pem \
> +	$(Q)openssl req -new -nodes -utf8 \
> +		-batch -config $(obj)/x509.genkey \
> +		-outform PEM -out $(obj)/signing_key.csr \
> +		-keyout $(obj)/signing_key.key -extensions myexts \
>  		$($(quiet)redirect_openssl)
> +	$(Q)openssl x509 -req -days 36500 -in $(obj)/signing_key.csr \
> +		-outform PEM -out $(obj)/signing_key.crt \
> +		-signkey $(obj)/signing_key.key \
> +		-$(CONFIG_MODULE_SIG_HASH) -extensions myexts \
> +		-extfile $(obj)/x509.genkey \
> +		$($(quiet)redirect_openssl)
> +	@cat $(obj)/signing_key.key $(obj)/signing_key.crt >> $(obj)/signing_key.pem
>  	@$(kecho) "###"
>  	@$(kecho) "### Key pair generated."
>  	@$(kecho) "###"
> -- 
> 2.18.1
> 
>