add acme-helper script

debian/bullseye/scripts/acme-helper.sh

@@ -0,0 +1,53 @@
+#!/bin/bash
+
+# Run this script with "(sudo) bash <filename> <args>".
+
+# Exit on error.
+#set -e
+# Debug
+set -eux
+
+# The Acme.sh user.
+ACME_USER='acme'
+
+# The Acme.sh group.
+ACME_GROUP='acme'
+
+# The acme.sh home.
+ACME_HOME='/etc/acme'
+
+# Where to download the acme.sh script.
+ACME_SCRIPT_URL='https://raw.githubusercontent.com/acmesh-official/acme.sh/master/acme.sh'
+
+# Temporary script location.
+ACME_SCRIPT_TMP='~/acme.sh'
+
+install() { 
+# Add user.
+adduser --system --disabled-login --gecos GECOS \
+        --no-create-home --home "${ACME_HOME}" "${ACME_USER}"
+
+# Lock the user.
+passwd -l "${ACME_USER}"
+
+# Add user to group if it exists otherwise add it & then add the user
+# to the group.
+usermod -aG ${ACME_GROUP} ${ACME_USER} || \
+    addgroup --system ${ACME_GROUP}
+    usermod -aG ${ACME_GROUP} ${ACME_USER}
+
+# Make the home dir.
+mkdir -v ${ACME_HOME}
+chown ${ACME_USER}:${ACME_GROUP} ${ACME_HOME}
+chmod -cR 750 ${ACME_HOME}
+chmod -cR u+s,g+s,o+s ${ACME_HOME}
+
+# Add needed binaries.
+apt install sudo socat curl tee
+
+# Download & install.
+sudo -s -u "${ACME_HOME}" curl -o "${ACME_SCRIPT_TMP}" "${ACME_SCRIPT_URL}" && ${ACME_SCRIPT_TMP} --install
+
+}
+
+${1} "$@"