Dockerfile

FROM alpine:3.22 AS base

RUN apk update && \
    apk add --no-cache bash git openssh rsync augeas shadow rssh && \
    deluser $(getent passwd 33 | cut -d: -f1) && \
    delgroup $(getent group 33 | cut -d: -f1) 2>/dev/null || true && \
    mkdir -p ~root/.ssh /etc/authorized_keys && chmod 700 ~root/.ssh/ && \
    augtool 'set /files/etc/ssh/sshd_config/AuthorizedKeysFile ".ssh/authorized_keys /etc/authorized_keys/%u"' && \
    echo -e "Port 22\n" >> /etc/ssh/sshd_config && \
    cp -a /etc/ssh /etc/ssh.cache && \
    rm -rf /var/cache/apk/* \
    ;

EXPOSE 22

COPY entry.sh /entry.sh

# Development image
FROM base AS development

RUN apk update && \
    apk add bats && \
    rm -rf /var/cache/apk/* \
    ;

# Release image
FROM base AS build
ENTRYPOINT ["/entry.sh"]
CMD ["/usr/sbin/sshd", "-D", "-e", "-f", "/etc/ssh/sshd_config"]