frp[cs]-daemon.sh: Reverse proxy to allow SSH into NAT'ed machine

This pair of scripts help run the FRP server/client programs as daemons,
and make it easy to configure a cron job to check and restart the
services if they are exited on errors.

2 files changed, 188 insertions, 0 deletions

diff --git a/unix/frpc-daemon.sh b/unix/frpc-daemon.sh
new file mode 100755
index 0000000..db6feda
--- /dev/null
+++ b/unix/frpc-daemon.sh
@@ -0,0 +1,92 @@
+#!/bin/sh
+#
+# Start the `FRP client' as a daemon, and start/check with a cron job.
+# https://github.com/fatedier/frp
+#
+# See start-stop-daemon(8)
+#
+# Example configuration file:
+# ---------------------------------------------------------------------
+# [common]
+# server_addr = xxx.xxx.xxx.xxx
+# server_port = xxxx
+#
+# [ssh]
+# type = tcp
+# local_ip = 127.0.0.1
+# local_port = 22
+# # port on the remote server that will be proxied to here
+# # e.g., ssh -p <remote_port> <user>@<server_addr>
+# remote_port = 2334
+# ---------------------------------------------------------------------
+#
+# Example cron job (check every 10th minutes):
+# */10  *  *  *  *  sh $HOME/bin/frpc-daemon.sh start >/dev/null 2>&1
+#
+#
+# Aaron LI
+# 2018-01-23
+#
+
+NAME=frpc
+PROGRAM=$HOME/local/frp/frpc
+CONFIG=$HOME/configs/${NAME}.ini
+PIDFILE=$HOME/.cache/${NAME}.pid
+LOGFILE=$HOME/.cache/${NAME}.log
+
+PATH=${PATH}:/usr/local/sbin:/usr/sbin:/sbin
+
+case "$1" in
+    start)
+        cmd=start
+        cmd_args="--start --make-pidfile --background"
+        ;;
+    stop)
+        cmd=stop
+        cmd_args="--stop --remove-pidfile --retry 5"
+        ;;
+    status)
+        cmd=status
+        cmd_args="--status"
+        ;;
+    *)
+        echo "usage: ${0##*/} {start|stop|status}"
+        exit 1
+        ;;
+esac
+
+start-stop-daemon ${cmd_args} \
+    --oknodo --verbose \
+    --name ${NAME} \
+    --pidfile ${PIDFILE} \
+    --startas ${PROGRAM} \
+    -- -c ${CONFIG} -L ${LOGFILE}
+ret=$?
+if [ "${cmd}" = "start" ]; then
+    if [ ${ret} -eq 0 ]; then
+        echo "Successfully started ${NAME} as PID $(cat ${PIDFILE})"
+    else
+        echo "Failed to start ${NAME}: ${PROGRAM}"
+        echo "Exit code: ${ret}"
+    fi
+elif [ "${cmd}" = "stop" ]; then
+    if [ ${ret} -eq 0 ]; then
+        echo "Successfully stopped ${NAME}: ${PROGRAM}"
+    else
+        echo "Failed to stop ${NAME}: ${PROGRAM}"
+        echo "Exit code: ${ret}"
+    fi
+elif [ "${cmd}" = "status" ]; then
+    if [ ${ret} -eq 0 ]; then
+        echo "${NAME} is running as PID $(cat ${PIDFILE})"
+    elif [ ${ret} -eq 1 ]; then
+        echo "${NAME} is not running but the PID file (${PIDFILE}) exists"
+    elif [ ${ret} -eq 3 ]; then
+        echo "${NAME} is not running"
+    else
+        echo "${NAME} in unknown status"
+        echo "Exit code: ${ret}"
+    fi
+else
+    echo "ERROR: unknown command: ${cmd}"
+fi
diff --git a/unix/frps-daemon.sh b/unix/frps-daemon.sh
new file mode 100755
index 0000000..c752ba8
--- /dev/null
+++ b/unix/frps-daemon.sh
@@ -0,0 +1,96 @@
+#!/bin/sh
+#
+# Start the `FRP server' as a daemon, and start/check with a cron job.
+# https://github.com/fatedier/frp
+#
+# See start-stop-daemon(8)
+#
+# Example configuration file:
+# ---------------------------------------------------------------------
+# [common]
+# bind_port = xxxx
+# ---------------------------------------------------------------------
+#
+# Example cron job (check every 10th minutes):
+# */10  *  *  *  *  sh $HOME/bin/frps-daemon.sh start >/dev/null 2>&1
+#
+# NOTE:
+# * If the machine that runs this `FRP server' is behind a NAT, then
+#   port forwarding for the above `bind_port' should be enabled.
+# * For each service that FRP proxies, e.g., SSH, an extra port will
+#   be bind to the server-side machine, as specified by the `remote_port'
+#   in the client-side configuration file.
+# * With only `bind_port' been forwarded, one can SSH into the server-side
+#   machine first, then SSH into the client-side machine through:
+#       ssh -p <remote_port> <user>@localhost
+# * With the extra `remote_port' been also forwarded, one can simply
+#   SSH into the client-side machine with:
+#       ssh -p <remote_port> <user>@<ip_server_side>
+#
+#
+# Aaron LI
+# 2018-01-23
+#
+
+NAME=frps
+PROGRAM=$HOME/local/frp/frps
+CONFIG=$HOME/configs/${NAME}.ini
+PIDFILE=$HOME/.cache/${NAME}.pid
+LOGFILE=$HOME/.cache/${NAME}.log
+
+PATH=${PATH}:/usr/local/sbin:/usr/sbin:/sbin
+
+case "$1" in
+    start)
+        cmd=start
+        cmd_args="--start --make-pidfile --background"
+        ;;
+    stop)
+        cmd=stop
+        cmd_args="--stop --remove-pidfile --retry 5"
+        ;;
+    status)
+        cmd=status
+        cmd_args="--status"
+        ;;
+    *)
+        echo "usage: ${0##*/} {start|stop|status}"
+        exit 1
+        ;;
+esac
+
+start-stop-daemon ${cmd_args} \
+    --oknodo --verbose \
+    --name ${NAME} \
+    --pidfile ${PIDFILE} \
+    --startas ${PROGRAM} \
+    -- -c ${CONFIG} -L ${LOGFILE}
+ret=$?
+if [ "${cmd}" = "start" ]; then
+    if [ ${ret} -eq 0 ]; then
+        echo "Successfully started ${NAME} as PID $(cat ${PIDFILE})"
+    else
+        echo "Failed to start ${NAME}: ${PROGRAM}"
+        echo "Exit code: ${ret}"
+    fi
+elif [ "${cmd}" = "stop" ]; then
+    if [ ${ret} -eq 0 ]; then
+        echo "Successfully stopped ${NAME}: ${PROGRAM}"
+    else
+        echo "Failed to stop ${NAME}: ${PROGRAM}"
+        echo "Exit code: ${ret}"
+    fi
+elif [ "${cmd}" = "status" ]; then
+    if [ ${ret} -eq 0 ]; then
+        echo "${NAME} is running as PID $(cat ${PIDFILE})"
+    elif [ ${ret} -eq 1 ]; then
+        echo "${NAME} is not running but the PID file (${PIDFILE}) exists"
+    elif [ ${ret} -eq 3 ]; then
+        echo "${NAME} is not running"
+    else
+        echo "${NAME} in unknown status"
+        echo "Exit code: ${ret}"
+    fi
+else
+    echo "ERROR: unknown command: ${cmd}"
+fi