fix(swarm): ignore announcements from peers with invalid announcement ports.

Author: SilentBot1

lib/server/swarm.js

@@ -37,6 +37,12 @@ class Swarm {
   announce (params, cb) {
     const self = this
     const id = params.type === 'ws' ? params.peer_id : params.addr
+
+    // Prevent invalid ports as this can be abused - issue: #512
+    if (params.port <= 0 || params.port > 65535) {
+      return cb(new Error('invalid port announced'))
+    }
+
     // Mark the source peer as recently used in cache
     const peer = self.peers.get(id)