Sign akmods automatically for Fedora 27.

sign-akmods.sh

#! /bin/bash

priv="/etc/pki/private/mok/signing_key.pem"
x509="/etc/pki/private/mok/signing_key.x509"

akdir="/var/cache/akmods"
kver="$(uname -r)"
sifi="/usr/src/kernels/${kver}/scripts/sign-file"
tmpf="/tmp/modsign_tmp.ko"

while pgrep -f -- '/sur/bin/akmods --from-kernel-posttrans' > /dev/null; do
    echo 'sign-akmods: waiting akmods finish...'
    sleep 1
done

readarray -t kos < <(
    find "${akdir}" -name "*${kver}*.rpm" -exec sh -c 'rpm -qlp "{}" | grep ".ko$"' \;
)
for ((i = 0; i < ${#kos[@]}; ++i)); do
    if ! strings "${kos[i]}" | tail -n1 | grep -q '~Module signature appended~'; then
        "${sifi}" sha256 "${priv}" "${x509}" "${kos[i]}"
        echo "sign-akmods:   newly signed '${kos[i]}'..."
    else
        echo "sign-akmods: already signed '${kos[i]}'..."
    fi
done

readarray -t koxzs < <(
    find "${akdir}" -name "*${kver}*.rpm" -exec sh -c 'rpm -qlp "{}" | grep ".ko.xz$"' \;
)
for ((i = 0; i < ${#koxzs[@]}; ++i)); do
    xz -dc "${koxzs[i]}" > "${tmpf}"
    if ! strings "${tmpf}" | tail -n1 | grep -q '~Module signature appended~'; then
        "${sifi}" sha256 "${priv}" "${x509}" "${tmpf}"
        xz -zc "${tmpf}" > "${koxzs[i]}"
        echo "sign-akmods:   newly signed '${koxzs[i]}'..."
    else
        echo "sign-akmods: already signed '${koxzs[i]}'..."
    fi
    rm -f "${tmpf}"
done

Added support for xz compressed kmods.
Original: https://gist.github.com/xenithorb/df08970b9e70bb3c6576e1fd91460afe