FROM scratch as base
ENV VERSION=5.19.6
ENV SRC_HASH=41a4f824af614460c429a7c723e8dcbb0e042f0047d328c18b4ed6f2b4efa63a
ENV SRC_FILE=linux-${VERSION}.tar.xz
ENV SRC_SITE=http://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/${SRC_FILE}
ENV NSM_VERSION=ed24913346a34d719afa2031299253160a2e3460
ENV NSM_SRC_HASH=720916a640f7579a1e9a972ddd43448d201b9ce4d4750079d8256e83be3e937c
ENV NSM_SRC_FILE=nsm.tgz
ENV NSM_SRC_SITE=https://codeload.github.com/aws/aws-nitro-enclaves-sdk-bootstrap/legacy.tar.gz/${NSM_VERSION}

FROM base as fetch
ADD --checksum=sha256:${SRC_HASH} ${SRC_SITE} .
ADD --checksum=sha256:${NSM_SRC_HASH} ${NSM_SRC_SITE} ${NSM_SRC_FILE}

FROM fetch as build
COPY --from=musl . /
COPY --from=make . /
COPY --from=binutils . /
COPY --from=linux-headers . /
COPY --from=elfutils . /
COPY --from=openssl . /
COPY --from=perl . /
COPY --from=m4 . /
COPY --from=gcc . /
COPY --from=bison . /
COPY --from=libzstd . /
COPY --from=zlib . /
COPY --from=flex . /
COPY --from=pkgconf . /
COPY --from=coreutils . /
COPY --from=findutils . /
COPY --from=diffutils . /
COPY --from=tar . /
COPY --from=gzip . /
COPY --from=xz . /
COPY --from=sed . /
COPY --from=grep . /
COPY --from=gawk . /
COPY --from=bc . /
COPY --from=bash . /
COPY --from=bash /bin/bash /bin/sh
RUN mkdir nitro-bootstrap
RUN tar -xf ${NSM_SRC_FILE} -C nitro-bootstrap --strip-components 1
RUN tar -xf ${SRC_FILE}
WORKDIR linux-${VERSION}
ADD linux.config .config
ENV KBUILD_BUILD_TIMESTAMP=1
RUN <<-EOF
	set -eux
	mkdir /tmp
	make olddefconfig
	make bzImage
	make modules_prepare
	cd ../nitro-bootstrap
	make -C ../linux-${VERSION} M=../nitro-bootstrap/nsm-driver
EOF
from build as package

FROM build as install
RUN <<-EOF
	set -eux
	mkdir /rootfs
	cp arch/x86_64/boot/bzImage /rootfs
	cp /nitro-bootstrap/nsm-driver/nsm.ko /rootfs
EOF
RUN find /rootfs -exec touch -hcd "@0" "{}" +

FROM scratch as package
COPY --from=install /rootfs /