T861: sign all Kernel modules with an ephemeral key

The shim review board (which is the secure boot base loader) recommends using
ephemeral keys when signing the Linux Kernel. This commit enables the Kernel
build system to generate a one-time ephemeral key that is used to:

* sign all build-in Kernel modules
* sign all other out-of-tree Kernel modules

The key lives in /tmp and is destroyed after the build container exits and is
named: "VyOS build time autogenerated kernel key".

In addition the Kernel now uses CONFIG_MODULE_SIG_FORCE. This now makes it
unable to load any Kernel Module to the image that is NOT signed by the
ephemeral key.

1 files changed, 6 insertions, 1 deletions

diff --git a/scripts/package-build/linux-kernel/build-intel-ixgbevf.sh b/scripts/package-build/linux-kernel/build-intel-ixgbevf.sh
index a965e0de..7d389832 100755
--- a/scripts/package-build/linux-kernel/build-intel-ixgbevf.sh
+++ b/scripts/package-build/linux-kernel/build-intel-ixgbevf.sh
@@ -72,6 +72,9 @@ fi
 echo "I: Building Debian package vyos-intel-${DRIVER_NAME}"
 cd ${CWD}
 
+# Sign generated Kernel modules
+${CWD}/sign-modules.sh ${DEBIAN_DIR}
+
 # delete non required files which are also present in the kernel package
 # und thus lead to duplicated files
 find ${DEBIAN_DIR} -name "modules.*" | xargs rm -f
@@ -97,4 +100,6 @@ fi
 if [ -d ${DEBIAN_DIR} ]; then
     rm -rf ${DEBIAN_DIR}
 fi
-
+if [ -f ${DEBIAN_POSTINST} ]; then
+    rm -f ${DEBIAN_POSTINST}
+fi