Add Docker image files

FROM debian:bookworm as entrypoint

LABEL org.opencontainers.image.title="Dovecot"

LABEL org.opencontainers.image.description="A popular mailbox server with LMTP and SASL"

LABEL org.opencontainers.image.authors="Dom Sekotill <dom.sekotill@kodo.org.uk>"

LABEL org.opencontainers.image.source="https://code.kodo.org.uk/docker/dovecot"

LABEL org.opencontainers.image.licenses="(MIT AND LGPv2)"

ARG DOVECOT_VERSION=">=1:2.3.19,<<1:2.3.20"

RUN --mount=source=install.bash,target=/install /install "${DOVECOT_VERSION}"

COPY dovecot.conf /etc/dovecot/

!include_try /usr/share/dovecot/protocols.d/*.protocol

# Default mount location for certificates is */etc/tls*

# Certificate chain is expected in *tls.crt*

# Private key is expected to be in *tls.key*

# These filenames are standard for a Kubernetes TLS secret

ssl_cert = </etc/tls/tls.crt

ssl_key = </etc/tls/tls.key

# These are some good defaults for TLS

ssl = required

ssl_min_protocol = TLSv1.2

ssl_cipher_list = DEFAULT

ssl_prefer_server_ciphers = yes

# User-supplied configurations, MAY override settings above

!include /etc/dovecot/conf.d/*.conf

# Log to stdio

log_path = /dev/stderr

info_log_path = /dev/stdout

# Users set up by Debian package

default_login_user = dovenull

default_internal_user = dovecot

#!/bin/bash

set -eu

PACKAGES=( dovecot-mysql dovecot-imapd dovecot-lmtpd )

RESTRICTIONS=()

IFS=,

for restriction in $1; do

	RESTRICTIONS+=( "dovecot-core ($restriction)" )

done

apt update

apt satisfy -y "${RESTRICTIONS[*]}" "${PACKAGES[@]}"

mkdir -p /usr/share/dovecot/config

# postinstall, remove most configuration

rm -r /etc/dovecot/*

# Make expected mount points and set ownership and permissions

mkdir --mode=0700 /etc/tls

chown root:root /etc/tls