# Maintainer: k1f0 <generic at k1f0.mozmail.com>
# Contributor: Levente Polyak <anthraxx[at]archlinux[dot]org>
# Contributor: Daniel Micay <danielmicay@gmail.com>
# Contributor: Tobias Powalowski <tpowa@archlinux.org>
# Contributor: Thomas Baechler <thomas@archlinux.org>

pkgbase=linux-hardened-cf
pkgver=6.5.7.hardened1
pkgrel=1
pkgdesc='Security-Hardened Linux with Cloudflare Patches'
url='https://github.com/anthraxx/linux-hardened'
arch=(x86_64)
license=(GPL2)
makedepends=(
  bc
  cpio
  gettext
  git
  libelf
  pahole
  perl
  python
  tar
  xz
  unzip
)
options=('!strip')
_srcname=linux-${pkgver%.*}
_srctag=${pkgver%.*}-${pkgver##*.}
source=(
  https://cdn.kernel.org/pub/linux/kernel/v${pkgver%%.*}.x/${_srcname}.tar.{xz,sign}
  https://github.com/anthraxx/linux-hardened/releases/download/${_srctag}/linux-hardened-${_srctag}.patch{,.sig}
  https://github.com/cloudflare/linux/archive/refs/heads/master.zip
  config  # the main kernel config file
)
validpgpkeys=(
  ABAF11C65A2970B130ABE3C479BE3E4300411886  # Linus Torvalds
  647F28654894E3BD457199BE38DBBDC86092693E  # Greg Kroah-Hartman
  E240B57E2C4630BA768E2F26FC1B547C8D8172C8  # Levente Polyak
)
b2sums=('a9bed9907bf4b22c08df8a8beaaf923648e4f0f1a4b00c11012871094e7c06a127e54bc1935edb8afc92999456c01ebabd04bc542a0e2fa16de0852a5f4be681'
        'SKIP'
        'ea5238fb1d9e9b028ac40de5a669ce3b413635a5229b9588166488ab97a3558ea9119d8bc540bee4c960da53195b85f4507d18fbe0f61de58f1629ae049ab85f'
        'SKIP'
        '7fea99533b3d9dc06cac7f0f5ff62d659981a2430a59c489f15f1ac4f4cfe3aad21a9af25a80e972331cab4d8f84d0cb28b35a41c7c812735e6bde78a333d35d'
        'eb5d106d6564c70170916c00bd5333a4fc624c426fc4ae3374fe9de55a93b3a0c28d7f9fd7a26d2280137f0e466565e7591062d86f6e4781f2ffd2c39bc431e4')

export KBUILD_BUILD_HOST=archlinux
export KBUILD_BUILD_USER=$pkgbase
export KBUILD_BUILD_TIMESTAMP="$(date -Ru${SOURCE_DATE_EPOCH:+d @$SOURCE_DATE_EPOCH})"

prepare() {
  cd $_srcname

  echo "Setting version..."
  echo "-$pkgrel" > localversion.10-pkgrel
  echo "${pkgbase#linux}" > localversion.20-pkgname

  local src
  for src in "${source[@]}"; do
    src="${src%%::*}"
    src="${src##*/}"
    [[ $src = *.patch ]] || continue
    echo "Applying patch $src..."
    patch -Np1 < "../$src"
  done

  # apply cloudflare patches
  CFSRC=$(ls ../linux-master/patches/0001*.patch)
  CFSRC="${CFSRC} $(ls ../linux-master/patches/0024*.patch)"
  for patch in $CFSRC; do
    echo "Applying Cloudflare patch $patch..."
    patch -Np1 < "$patch"
  done

  echo "Setting config..."
  cp ../config .config
  make -j$(nproc) olddefconfig
  diff -u ../config .config || :

  make -j$(nproc) -s kernelrelease > version
  echo "Prepared $pkgbase version $(<version)"
}

build() {
  cd $_srcname

  make -j$(nproc) all
}

_package() {
  pkgdesc="The $pkgdesc kernel and modules"
  depends=(
    coreutils
    initramfs
    kmod
  )
  optdepends=(
    'wireless-regdb: to set the correct wireless channels of your country'
    'linux-firmware: firmware images needed for some devices'
    'usbctl: deny_new_usb control'
  )
  provides=(
    KSMBD-MODULE
    VIRTUALBOX-GUEST-MODULES
    WIREGUARD-MODULE
  )

  cd $_srcname
  local modulesdir="$pkgdir/usr/lib/modules/$(<version)"

  echo "Installing boot image..."
  # systemd expects to find the kernel here to allow hibernation
  # https://github.com/systemd/systemd/commit/edda44605f06a41fb86b7ab8128dcf99161d2344
  install -Dm644 "$(make -s image_name)" "$modulesdir/vmlinuz"

  # Used by mkinitcpio to name the kernel
  echo "$pkgbase" | install -Dm644 /dev/stdin "$modulesdir/pkgbase"

  echo "Installing modules..."
  ZSTD_CLEVEL=19 make INSTALL_MOD_PATH="$pkgdir/usr" INSTALL_MOD_STRIP=1 \
    DEPMOD=/doesnt/exist modules_install  # Suppress depmod

  # remove build and source links
  rm "$modulesdir"/{source,build}
}

_package-headers() {
  pkgdesc="Headers and scripts for building modules for the $pkgdesc kernel"
  depends=(pahole)

  cd $_srcname
  local builddir="$pkgdir/usr/lib/modules/$(<version)/build"

  echo "Installing build files..."
  install -Dt "$builddir" -m644 .config Makefile Module.symvers System.map \
    localversion.* version vmlinux
  install -Dt "$builddir/kernel" -m644 kernel/Makefile
  install -Dt "$builddir/arch/x86" -m644 arch/x86/Makefile
  cp -t "$builddir" -a scripts

  # required when STACK_VALIDATION is enabled
  install -Dt "$builddir/tools/objtool" tools/objtool/objtool

  # required when DEBUG_INFO_BTF_MODULES is enabled
  # install -Dt "$builddir/tools/bpf/resolve_btfids" tools/bpf/resolve_btfids/resolve_btfids

  echo "Installing headers..."
  cp -t "$builddir" -a include
  cp -t "$builddir/arch/x86" -a arch/x86/include
  install -Dt "$builddir/arch/x86/kernel" -m644 arch/x86/kernel/asm-offsets.s

  install -Dt "$builddir/drivers/md" -m644 drivers/md/*.h
  install -Dt "$builddir/net/mac80211" -m644 net/mac80211/*.h

  # https://bugs.archlinux.org/task/13146
  install -Dt "$builddir/drivers/media/i2c" -m644 drivers/media/i2c/msp3400-driver.h

  # https://bugs.archlinux.org/task/20402
  install -Dt "$builddir/drivers/media/usb/dvb-usb" -m644 drivers/media/usb/dvb-usb/*.h
  install -Dt "$builddir/drivers/media/dvb-frontends" -m644 drivers/media/dvb-frontends/*.h
  install -Dt "$builddir/drivers/media/tuners" -m644 drivers/media/tuners/*.h

  # https://bugs.archlinux.org/task/71392
  install -Dt "$builddir/drivers/iio/common/hid-sensors" -m644 drivers/iio/common/hid-sensors/*.h

  echo "Installing KConfig files..."
  find . -name 'Kconfig*' -exec install -Dm644 {} "$builddir/{}" \;

  echo "Removing unneeded architectures..."
  local arch
  for arch in "$builddir"/arch/*/; do
    [[ $arch = */x86/ ]] && continue
    echo "Removing $(basename "$arch")"
    rm -r "$arch"
  done

  echo "Removing documentation..."
  rm -r "$builddir/Documentation"

  echo "Removing broken symlinks..."
  find -L "$builddir" -type l -printf 'Removing %P\n' -delete

  echo "Removing loose objects..."
  find "$builddir" -type f -name '*.o' -printf 'Removing %P\n' -delete

  echo "Stripping build tools..."
  local file
  while read -rd '' file; do
    case "$(file -Sib "$file")" in
      application/x-sharedlib\;*)      # Libraries (.so)
        strip -v $STRIP_SHARED "$file" ;;
      application/x-archive\;*)        # Libraries (.a)
        strip -v $STRIP_STATIC "$file" ;;
      application/x-executable\;*)     # Binaries
        strip -v $STRIP_BINARIES "$file" ;;
      application/x-pie-executable\;*) # Relocatable binaries
        strip -v $STRIP_SHARED "$file" ;;
    esac
  done < <(find "$builddir" -type f -perm -u+x ! -name vmlinux -print0)

  echo "Stripping vmlinux..."
  strip -v $STRIP_STATIC "$builddir/vmlinux"

  echo "Adding symlink..."
  mkdir -p "$pkgdir/usr/src"
  ln -sr "$builddir" "$pkgdir/usr/src/$pkgbase"
}

pkgname=(
  "$pkgbase"
  "$pkgbase-headers"
)

for _p in "${pkgname[@]}"; do
  eval "package_$_p() {
    $(declare -f "_package${_p#$pkgbase}")
    _package${_p#$pkgbase}
  }"
done