Compiling arch packages and PGP signature

I am trying to download and compile the linux kernel according to the arch wiki. But at the step where I want to build a package

makepkg -s

I get the following error about package signature

==> Making package: linux6-custom 6.0.arch1-1 (Sat 08 Oct 2022 04:30:41 PM MDT)
==> Checking runtime dependencies...
==> Checking buildtime dependencies...
==> Retrieving sources...
  -> Updating archlinux-linux git repo...
  -> Found config
==> Validating source files with sha256sums...
    archlinux-linux ... Skipped
    config ... Passed
==> Verifying source file signatures with gpg...
    archlinux-linux git repo ... FAILED (unknown public key 3B94A80E50A477C7)
==> ERROR: One or more PGP signatures could not be verified!

I think this is also relevant if I want to download a package from the AUR and build it.

Question: Do I need to import that keyring via gpg --recv-key 3B94A80E50A477C7 , is that safe? doing a gpg --search-keys 3B94A80E50A477C7 indicates that its from Jan Alexander Steffens (heftig).

Explanation of error message: I found this on the manjaro forum that seems to explain it in better words than I could

Your user starts with an empty keyring. That is, you trust no one’s keys. When you run makepkg you run it as your normal user, so if the PKGBUILD file contains a PGP key validation will fail because you don’t trust the key - you have to import the key into your keyring first.

actually 3B94A80E50A477C7 doesn’t work. It says

$ gpg --recv-keys 3B94A80E50A477C7
gpg: key 19802F8B0D70FC30: rejected by import screener
gpg: Total number processed: 1

adding that other key does not solve the problem. I don’t understand where the PKGBUILD is trying to get that key, it’s not in the list from what I can tell

PKGBUILD
# Maintainer: Jan Alexander Steffens (heftig) <heftig@archlinux.org>

pkgbase=linux6-custom
pkgver=6.0.arch1
pkgrel=1
pkgdesc='Linux'
_srctag=v${pkgver%.*}-${pkgver##*.}
url="https://github.com/archlinux/linux/commits/$_srctag"
arch=(x86_64)
license=(GPL2)
makedepends=(
  bc libelf pahole cpio perl tar xz
  xmlto python-sphinx python-sphinx_rtd_theme graphviz imagemagick texlive-latexextra
  git
)
options=('!strip')
_srcname=archlinux-linux
source=(
  "$_srcname::git+https://github.com/archlinux/linux?signed#tag=$_srctag"
  config         # the main kernel config file
)
validpgpkeys=(
  'ABAF11C65A2970B130ABE3C479BE3E4300411886'  # Linus Torvalds
  '647F28654894E3BD457199BE38DBBDC86092693E'  # Greg Kroah-Hartman
  'A2FF3A36AAA56654109064AB19802F8B0D70FC30'  # Jan Alexander Steffens (heftig)
  'C7E7849466FE2358343588377258734B41C31549'  # David Runge <dvzrv@archlinux.org>
)
sha256sums=('SKIP'
            '85f7327e262056043514a24eb6c8d46e3ac6a10a6caff09d664dec8827829144')

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..."
  scripts/setlocalversion --save-scmversion
  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

  echo "Setting config..."
  cp ../config .config
  make olddefconfig
  diff -u ../config .config || :

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

build() {
  cd $_srcname
  make htmldocs
}

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

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

  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..."
  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 "$(file -bi "$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"
}

_package-docs() {
  pkgdesc="Documentation for the $pkgdesc kernel"

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

  echo "Installing documentation..."
  local src dst
  while read -rd '' src; do
    dst="${src#Documentation/}"
    dst="$builddir/Documentation/${dst#output/}"
    install -Dm644 "$src" "$dst"
  done < <(find Documentation -name '.*' -prune -o ! -type d -print0)

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

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

# vim:set ts=8 sts=2 sw=2 et:

Could you try:

gpg --recv-keys --keyserver hkps://keys.openpgp.org 3B94A80E50A477C7

?

that solved it! I don’t know where it is trying to pull this in my PKDBUILD.

Thank you, my kernel is building, my laptop fans are running high speed!

1 Like

Perhaps some keyserver not responding as it should. Not sure which one.

Thanks. At least I learned something about gpg keys today, maybe useful when I try building packages from AUR.

1 Like

This topic was automatically closed 2 days after the last reply. New replies are no longer allowed.