get-fedora-latest-config

#!/bin/bash
# vim: set ts=4 sw=4 sts=4 et :

set -e
if [ "${VERBOSE:-0}" -ge 2 ] || [ "${DEBUG:-0}" -eq 1 ]; then
    debug=1
    set -x
fi

exit_clean() {
    local exit_code=$?
    if [ -n "$tmpdir" ]; then
        rm -rf "$tmpdir"
    fi
    if [ ${exit_code} != 0 ]; then
        errecho "Unable to find the latest kernel rpm for Fedora $releasever";
    fi
    exit "${exit_code}"
}

errecho() {
    >&2 echo "$@"
}

usage() {
errecho "Usage: $0 [OPTIONS]... []

This script is used for fetching latest Fedora kernel config for the current
kernel version used by Qubes.

Options:
    --releasever <Fedora RELEASEVER>    Fedora release version to use. Default is latest.
    --include-testing                   Include testing updates repository
    --include-rc                        Include release candidate kernels

Remark:
    Ensure to have downloaded kernel sources in local directory (make get-sources).
"
    exit 1
}

get_releasever() {
    releasever="$1"
    # example of releasever: '29' or 'rawhide'
    if [ -n "$releasever" ]; then
        if [[ ! "$releasever" =~ ^[1-9][0-9]$ ]] && [ "$releasever" != "rawhide" ]; then
            errecho "Invalid release format"
            exit 1
        fi
    elif [ -z "$releasever" ]; then
        releasever="$(git ls-remote --heads https://src.fedoraproject.org/rpms/fedora-release | grep -Po "refs/heads/f[0-9][1-9]*" | sed 's#refs/heads/f##g' | sort -g | tail -1)"
        if ! [[ "$releasever" =~ ^[1-9][0-9]$ ]]; then
            errecho "An error occurred while trying to determine latest Fedora version"
            exit 1
        fi
    fi
    echo "$releasever"
}

localdir="$(dirname "$(readlink -f "$0")")"
kernelver="$(cat "$localdir/version")"
kernelsrc="linux-$kernelver"
kernelarchive="$kernelsrc.tar"

if ! OPTS=$(getopt -o hv:t:r: --long help,releasever:,include-testing,include-rc -n "$0" -- "$@"); then
    errecho "An error occurred while parsing options."
    exit 1
fi

eval set -- "$OPTS"

while [[ $# -gt 0 ]]; do
    case "$1" in
        -a | --releasever ) releasever="$2"; shift ;;
        -m | --include-testing ) ktesting="1";;
        -i | --include-rc ) krc="1";;
        -h | --help) usage ;;
    esac
    shift
done

if [ ! -e "$localdir/$kernelarchive" ]; then
    errecho "Cannot find $kernelarchive in local directory."
    exit 1
fi

trap 'exit_clean' 0 1 2 3 6 15

releasever=$(get_releasever "$releasever")

# get the latest kernel rpm
repo_opts="--disablerepo=* --enablerepo=fedora --enablerepo=updates --releasever=$releasever"

# include testing
if [ "$ktesting" == "1" ]; then
repo_opts="$repo_opts --enablerepo=updates-testing"
fi

# shellcheck disable=SC2086
latestver=$(dnf -q repoquery kernel-core $repo_opts)

# include rc
if [ "$krc" != "1" ]; then
latestver=$(echo "$latestver" | grep -v "rc[0-9]*")
fi

latestver=$(echo "$latestver" | sort -V | tail -1 | cut -d ':' -f2)
latestrpm="kernel-core-$latestver.rpm"

if [ "$releasever" == 'rawhide' ]; then
    releasever="$(echo "$latestver" | grep -o "fc[1-9][0-9]" | sed 's/fc//')"
fi

if [ -n "$latestrpm"  ] && [ -n "$releasever" ]; then
    key="$localdir/../builder-rpm/keys/RPM-GPG-KEY-fedora-$releasever-primary"
    tmpdir="$(mktemp -d -p "$localdir")"
    # download latest kernel rpm
    # shellcheck disable=SC2086
    dnf -q download kernel-core $repo_opts
    mv "$latestrpm" "$tmpdir/$latestrpm.untrusted"

    # check signature
    mkdir -p "$tmpdir/rpmdb"
    rpmkeys --dbpath="$tmpdir/rpmdb" --import "$key"
    { rpmkeys --dbpath="$tmpdir/rpmdb" --checksig "$tmpdir/$latestrpm.untrusted" | grep -q 'signatures OK' ; } || { errecho "Failed to check signature"; exit 1; }
    mv "$tmpdir/$latestrpm.untrusted" "$tmpdir/$latestrpm"

    # extract kernel sources in qubes-linux-kernel
    tar xf "$localdir/$kernelarchive" -C "$tmpdir"

    # get latest config and put it in extracted sources
    rpm2cpio "$tmpdir/$latestrpm" | cpio --quiet -i --to-stdout "./lib/modules/$latestver/config" > "$tmpdir/$kernelsrc/.config"

    # generate new config with: yes '' | make oldconfig
    cd "$tmpdir/$kernelsrc/"
    ## drop config settings which depend on Fedora patches and adjust for the small version difference
    if [ "$debug" == "1" ]; then
        yes '' | make oldconfig
    else
        yes '' | make oldconfig > /dev/null 2>&1
    fi
    ## remove comments in header
    sed -i '1,4d' "$tmpdir/$kernelsrc/.config"

    # create final config
    cat - "$tmpdir/$kernelsrc/.config" > "$localdir/config-base-$(echo "$latestver" | cut -d '-' -f1)" << EOF
# Base config based on Fedora's config ($latestrpm)
# Only modification is \`yes '' | make oldconfig\` to drop config settings which
# depend on Fedora patches and adjust for the small version difference.
EOF
else
    exit 1
fi