feat(backend/routes): add sync check between web and firewall

web/backend/src/routes/firewall.ts

@@ -1,27 +1,74 @@
 import { Router } from "express"
-import { cerberoEventEmitter, isFirewallConnected } from "../socket/socket"
+import { Database } from "../database/db"
+import { buildConfiguration, cerberoEventEmitter, isFirewallConnected } from "../socket/socket"
 
 const firewallRoute = Router()
 
-firewallRoute.get("/", (req, res) => {
-  // Get the last config that was sent from the db and
-  // compare it to the current web config
+firewallRoute.get("/", async (req, res) => {
+  const redis = Database.getInstance()
 
+  const config = await buildConfiguration()
+  const firewallConfig = []
+  const firewallServicesKeys = await redis.keys("firewall:services:*")
+
+  for(const firewallServiceKey of firewallServicesKeys) {
+    const nfq = firewallServiceKey.split(":")[2]
+    const firewallService = await redis.hGetAll(firewallServiceKey)
+    const regexes = await redis.sMembers(`firewall:regexes:${nfq}`)
+
+    const parsedFirewallService = {
+      chain: "OUTPUT",
+      name: firewallService.name,
+      nfq: parseInt(firewallService.nfq),
+      port: parseInt(firewallService.port),
+      protocol: firewallService.protocol as "tcp" | "udp",
+      regexes: regexes
+    }
+
+    firewallConfig.push(parsedFirewallService)
+  }
+
+  // The order of the regexes MATTERS!
+  // If the regexes stay the same but their order changes the firewall is condidered NOT SYNCED!
   return res.json({
     isConnected: isFirewallConnected,
-    isSynced: true
+    isSynced: JSON.stringify(firewallConfig) === JSON.stringify(config)
   })
 })
 
 // Trigger a firewall configuration update
-firewallRoute.post("/", (req, res) => {
+firewallRoute.post("/", async (req, res) => {
+  const redis = Database.getInstance()
+
   if(!isFirewallConnected) {
     return res.status(409).json({
       error: "The firewall is not connected, can't update the configuration"
     })
   }
 
-  cerberoEventEmitter.emit("cerberoConfigUpdate")
+  // Update the "firewall config" in the db
+  // Take the "web config" and override the firewall one
+  const firewallKeys = await redis.keys("firewall:*")
+  for(const firewallKey of firewallKeys) {
+    await redis.del(firewallKey)
+  }
+
+  const servicesKeys = await redis.keys("services:*")
+  const regexesKeys = await redis.keys("regexes:*:active")
+
+  for(const serviceKey of servicesKeys) {
+    await redis.copy(serviceKey, `firewall:${serviceKey}`)
+  }
+
+  for(const regexesKey of regexesKeys) {
+    const regexesKeyParts = regexesKey.split(":")
+    const newRegexesKey = regexesKeyParts.filter((_, i) => i !== regexesKeyParts.length - 1).join(":")
+
+    await redis.copy(regexesKey, `firewall:${newRegexesKey}`)
+  }
+
+
+  cerberoEventEmitter.emit("cerberoConfigUpdate") // FIX: an update could fail inside of this and we would have updated the db anyways
 
   return res.status(204).end()
 })