Dockerfile_bash

FROM middagj/kaniko-base

ARG gnu_mirror=https://ftp.snt.utwente.nl/pub/software/gnu
ARG bash_version=5.2.37

# Download public key
RUN gpg --batch --keyserver keyserver.ubuntu.com --recv-keys '7C0135FB088AAF6C66C650B9BB5869F064EA74AB' \
 && gpg --import-ownertrust <<< '7C0135FB088AAF6C66C650B9BB5869F064EA74AB:6:'

# Download
RUN curl -fsSL -o /tmp/bash.tar.gz "${gnu_mirror}/bash/bash-${bash_version}.tar.gz" \
 && curl -fsSL -o /tmp/bash.tar.gz.sig "${gnu_mirror}/bash/bash-${bash_version}.tar.gz.sig" \
 && gpg --verify /tmp/bash.tar.gz.sig \
 && tar -xzf /tmp/bash.tar.gz \
 && mv bash* bash \
 && rm -f /tmp/bash*

# Compile
RUN cd bash \
 && FORCE_UNSAFE_CONFIGURE=1 \
    CC='musl-gcc' \
    CFLAGS='-Os -ffunction-sections -fdata-sections' \
    LDFLAGS='-Wl,--gc-sections' \
    ./configure --without-bash-malloc \
 && make bash

# Install
RUN mv bash/bash /busybox/bin

# Clean /busybox
RUN while IFS= read -r file; do \
      strip -s -R .comment -R .gnu.version --strip-unneeded "$file" ; \
    done < <(find -- /busybox/bin -type f | sort)