Synology Docker: update entrypoint.sh (#1704)

* update entrypoint.sh

- propagate TERM/QUIT/INT signals
- add some basic logging
- check for unbound variables
- update "route helper"
   - run as subshell, exit if zerotier-one is unavailable so pod can be restarted
   - only call `zerotier-cli` once, avoids race conditions
   - only add default routes if allowDefault is enabled for that network
   - add some more error handling
   - sleep after all networks are processed

* switch to polling ZT service at startup

Co-authored-by: Daniel Quinlan <dq@chaosengine.net>

pkg/synology/dsm7-docker/entrypoint.sh

@@ -1,29 +1,81 @@
 #!/bin/bash
 
+set -uo pipefail
+
+trap 'trap " " SIGTERM; kill 0; wait' SIGTERM SIGQUIT SIGINT
+
+echo "Starting Zerotier-One"
 zerotier-one -d
 
-# Wait for ZT service to come online before attempting queries
-sleep 15
+echo "Wait for ZT service to come online before attempting queries..."
+MAX_WAIT_SECS="${MAX_WAIT_SECS:-90}"
+SLEEP_TIME="${SLEEP_TIME:-15}"
+if [[ "$SLEEP_TIME" -le 0 ]]
+then
+  SLEEP_TIME=1
+fi
 
+iterations=$((MAX_WAIT_SECS/SLEEP_TIME))
+online=false
+
+for ((s=0; s<=iterations; s++))
+do
+    online="$(zerotier-cli -j info | jq '.online' 2>/dev/null)"
+    if [[ "$online" == "true" ]]
+    then
+        break
+    fi
+    sleep "$SLEEP_TIME"
+    echo " ."
+done
+
+if [[ "$online" != "true" ]]
+then
+    echo "Waited $MAX_WAIT_SECS for zerotier-one to start, exiting." >&2
+    exit 1
+fi
+echo "done."
+
+(
+echo "Starting route helper"
 while true
 do
-    NETWORK_COUNT=$(zerotier-cli -j listnetworks | jq -r '. | length')
-    if [ "$NETWORK_COUNT" -gt 0 ]; then
+    if ! NETWORK_LIST="$(zerotier-cli -j listnetworks)"
+    then
+      echo "Route helper: $NETWORK_LIST" >&2
+      exit 1
+    fi
+    NETWORK_COUNT="$(jq -r '. | length' <<< "$NETWORK_LIST")"
+    if [[ "$NETWORK_COUNT" -gt 0 ]]
+    then
         for ((j=0; j<=$((NETWORK_COUNT-1)); j++))
         do
-            ROUTE_COUNT=$(zerotier-cli -j listnetworks | jq -r '.['$j'].routes | length')
+            ALLOW_DEFAULT="$(jq -r '.['$j'].allowDefault' <<< "$NETWORK_LIST")"
+            ROUTE_COUNT="$(jq -r '.['$j'].routes | length' <<< "$NETWORK_LIST")"
             for ((k=0; k<=$((ROUTE_COUNT-1)); k++))
             do
-                ROUTE=$(zerotier-cli -j listnetworks | jq -r '.['$j'].routes['$k'].target')
-                EXIST=$(ip route show $ROUTE | wc -l)
-                if [ $EXIST -eq 0 ];
+                ROUTE="$(jq -r '.['$j'].routes['$k'].target' <<< "$NETWORK_LIST")"
+                if [[ -n "$ROUTE" ]]
                 then
-                    IFNAME=$(zerotier-cli -j listnetworks | jq -r '.['$j'] | .portDeviceName')
-                    ip route add $ROUTE dev $IFNAME
-                    # Routes will be deleted when ZT brings the interface down
+                    # check if route is default and allowDefault enabled for this network
+                    if [[ "$ROUTE" == "0.0.0.0/0" && "$ALLOW_DEFAULT" == "false" ]]
+                    then
+                      continue
+                    fi
+                    EXIST="$(ip -o route show "$ROUTE")"
+                    if [[ -z "${EXIST}" ]]
+                    then
+                        IFNAME="$(jq -r '.['$j'] | .portDeviceName' <<< "$NETWORK_LIST")"
+                        echo " Adding route $ROUTE to dev $IFNAME"
+                        ip route add "$ROUTE" dev "$IFNAME"
+                        # Routes will be deleted when ZT brings the interface down
+                    fi
                 fi
             done
         done
-        sleep 15
     fi
-done
+    sleep 15
+done ) &
+
+wait
+