init

userrc.in

@@ -0,0 +1,120 @@
+#!/usr/bin/env bash
+
+msg() { printf '%s\n' "$*"; }
+err() { printf '%s\n' "$*" >&2; }
+
+usage() {
+	msg "Usage: userrc [-c config] [-l logdir]"
+}
+
+rc_run_wait() {
+	su "$username" -s "$SHELL" -c "$homedir/.config/rc.local" &>"$logdir/${username}.log" &
+	wait "$!"
+
+	if (( $? )); then
+		msg "$homedir/.config/rc.local has returned a non-zero exit code."
+	fi
+}
+
+is_blacklisted() {
+	declare u target=$1
+
+	for u in "${users_deny[@]}"; do
+		if [[ "$u" == "$target" ]]; then
+			return 0
+		fi
+	done
+
+	return 1
+}
+
+is_whitelisted() {
+	declare u target=$1
+
+	for u in "${users_allow[@]}"; do
+		if [[ "$u" == "$target" ]]; then
+			return 0
+		fi
+	done
+
+	return 1
+}
+
+get_allowed_users() {
+	if ! [[ "$access_mode" ]]; then
+		access_mode='blacklist'
+	fi
+
+	msg "Running in $access_mode access mode."
+
+	case "${access_mode:-freeforall}" in
+		explicit)
+			while IFS=':' read -r username pass uid gid description homedir shell; do
+				if is_whitelisted "$username"; then
+					users+=( "$username:$homedir" )
+				fi
+			done < /etc/passwd
+		;;
+
+		blacklist)
+			while IFS=':' read -r username pass uid gid description homedir shell; do
+				if ! is_blacklisted "$username"; then
+					users+=( "$username:$homedir" )
+				fi
+			done < /etc/passwd
+		;;
+	esac
+}
+
+runtime_config() {
+	config='/etc/userrc.conf'
+	cfg_logdir='/tmp/userrc'
+
+	while (( $# )); do
+		case "$1" in
+			(-c) config="$2"; shift;;
+			(-l) logdir="$2"; shift;;
+		esac
+		shift
+	done
+
+	if [[ -f "$config" ]]; then
+		source "$config" || { return $?; }
+	else
+		msg "Config not found at $config. Using defaults."
+	fi
+
+	if ! [[ "$logdir" ]]; then
+		logdir="$cfg_logdir"
+	fi
+
+	if [[ ! -d "$logdir" ]]; then
+		mkdir -p "$logdir" || {
+			return 1
+		}
+	fi
+
+	chmod 700 "$logdir"
+}
+
+main() {
+	runtime_config
+	get_allowed_users
+
+	for u in "${users[@]}"; do
+		IFS=':' read -r username homedir <<< "$u"
+
+		if [[ "$homedir" && "$homedir" != '/' ]]; then
+			if [[ -f "$homedir/.config/rc.local" ]]; then
+				if [[ -x "$homedir/.config/rc.local" ]]; then
+					msg "Executing $homedir/.config/rc.local"
+					rc_run_wait
+				else
+					msg "$homedir/.config/rc.local exists, but is not executable"
+				fi
+			fi
+		fi
+	done
+}
+
+main "$@"