On Tue, 2022-06-21 at 14:19 -0400, Kenton Groombridge wrote: > eee74b9fca1 adds support for module compression, but this breaks > loading > out of tree modules when module signing is enforced because modules > must > be signed before they are compressed. Additionally, the recommended > Portage hook[1] no longer works with this change. > > Add module signing support in linux-mod.eclass which more or less > does > exactly what the aforementioned Portage hook does. If the kernel > configuration has CONFIG_MODULE_SIG_ALL=y, then read the hash and > keys > from the kernel configuration and call the sign_file tool to sign the > module before it is compressed. > > Bug: https://bugs.gentoo.org/show_bug.cgi?id=447352 > Signed-off-by: Kenton Groombridge <[email protected]> > --- > eclass/linux-mod.eclass | 16 ++++++++++++++++ > 1 file changed, 16 insertions(+) > > diff --git a/eclass/linux-mod.eclass b/eclass/linux-mod.eclass > index b7c13cbf7e7..fd40f6d7c6c 100644 > --- a/eclass/linux-mod.eclass > +++ b/eclass/linux-mod.eclass > @@ -712,6 +712,22 @@ linux-mod_src_install() { > cd "${objdir}" || die "${objdir} does not exist" > insinto > "${INSTALL_MOD_PATH}"/lib/modules/${KV_FULL}/${libdir} > > + # check here for CONFIG_MODULE_SIG_ALL and sign the > module being built if enabled. > + # modules must be signed before they are compressed. > + > + if linux_chkconfig_present MODULE_SIG_ALL; then > + local > module_sig_hash="$(linux_chkconfig_string MODULE_SIG_HASH)" > + local > module_sig_key="$(linux_chkconfig_string MODULE_SIG_KEY)" > + module_sig_key="${module_sig_key:- > certs/signing_key.pem}" > + if [[ "${module_sig_key#pkcs11:}" == > "${module_sig_key}" && "${module_sig_key#/}" == "${module_sig_key}" > ]]; then > + local > key_path="${KERNEL_DIR}/${module_sig_key}" > + else > + local key_path="${module_sig_key}" > + fi > + local > cert_path="${KERNEL_DIR}/certs/signing_key.x509" > + "${KERNEL_DIR}"/scripts/sign-file > ${module_sig_hash//\"} ${key_path//\"} ${cert_path} > ${modulename}.${KV_OBJ} > + fi > + > # check here for CONFIG_MODULE_COMPRESS_<compression > option> (NONE, GZIP, XZ, ZSTD) > # and similarily compress the module being built if > != NONE. >
Hi, I've spent some time in the past ( circa 2018 ) to get this in, but gave up due to various reasons, I was not a gentoo dev yet at the time. I can't see how posted implementation will work tbh. portage will strip signature out of the module, unless you prevent stripping completely or package uses EAPI>=7, and omits stripping modules via dostrip -x on the ko object. kernel will NOT load module with stripped signature. so either you have to sign in pkg_postinst phase, or prevent stripping. signing in postinst is not ideal, because if breaks recorded file checksums in vdb. here's old fork of eclass I made, maybe you can find some helpful code in there https://github.com/gyakovlev/linux-mod.eclass/blob/master/linux-mod.eclass old ML discussion we had: https://archives.gentoo.org/gentoo-dev/message/4b15b1c851f379a1f802e2f2895cdfa8 You will also need a dependency on openssl, since sign-file uses it. lmk if you need more info, I might remember more details, but for now that's all I have. I'll try to help get it done, but my availability is spotty due to limited time.
