client packet verification

src/ConnWorker.js

@@ -1,4 +1,4 @@
-const RakClient = require('@jsprismarine/raknet/client')
+const RakClient = require('jsp-raknet/client')
 const { Worker, isMainThread, parentPort } = require('worker_threads')
 const EncapsulatedPacket = require('@jsprismarine/raknet/protocol/encapsulated_packet')
 

src/client.js

@@ -119,18 +119,55 @@ class Client extends Connection {
     process.exit(1)
   }
 
+  tryRencode(name, params, actual) {
+    if (name == 'level_chunk') {
+      console.log("Skipping chunk validation, it's broken right now")
+      return
+    }
+    const packet = this.serializer.createPacketBuffer({ name, params })
+
+    console.assert(packet.toString('hex') == actual.toString('hex'))
+    if (packet.toString('hex') !== actual.toString('hex')) {
+
+      const ours = packet.toString('hex').match(/.{1,16}/g).join('\n')
+      const theirs = actual.toString('hex').match(/.{1,16}/g).join('\n')
+
+      fs.writeFileSync('ours.txt', ours)
+      fs.writeFileSync('theirs.txt', theirs)
+      fs.writeFileSync('ours.json', serialize(params))
+      fs.writeFileSync('theirs.json', serialize(this.deserializer.parsePacketBuffer(packet).data.params))
+
+      throw new Error(name + ' Packet comparison failed!')
+    }
+  }
+
   readPacket(packet) {
     // console.log('packet', packet)
     const des = this.deserializer.parsePacketBuffer(packet)
     const pakData = { name: des.data.name, params: des.data.params }
     console.log('->', pakData.name, serialize(pakData.params).slice(0, 100))
+
+    // No idea what this exotic 0xA0 packet is, it's not implemented anywhere
+    // and seems empty. Possible gibberish from the raknet impl
+    if (pakData.name == '160' || !pakData.name) { // eslint-ignore-line
+      console.warn('?? Ignoring extraneous packet ', des)
+      return
+    }
+
+    // Packet verifying (decode + re-encode + match test)
+    if (pakData.name) {
+      this.tryRencode(pakData.name, pakData.params, packet)
+    }
+
     // console.info('->', JSON.stringify(pakData, (k,v) => typeof v == 'bigint' ? v.toString() : v))
+    // Packet dumping
     try {
       if (!fs.existsSync(`./packets/${pakData.name}.json`)) {
         fs.writeFileSync(`./packets/${pakData.name}.json`, serialize(pakData.params, 2))
         fs.writeFileSync(`./packets/${pakData.name}.txt`, packet.toString('hex'))
       }
-    } catch {}
+    } catch { }
+
     switch (des.data.name) {
       case 'server_to_client_handshake':
         this.emit('client.server_handshake', des.data.params)
@@ -143,6 +180,10 @@ class Client extends Connection {
         break
       case 'start_game':
         fs.writeFileSync('start_game.json', JSON.stringify(des.data.params, (k, v) => typeof v == 'bigint' ? v.toString() : v))
+        break
+      case 'level_chunk':
+        fs.writeFileSync(`./chunks/chunk-${chunks++}.txt`, packet.toString('hex'))
+        break
       default:
       // console.log('Sending to listeners')
     }
@@ -151,6 +192,8 @@ class Client extends Connection {
   }
 }
 
+var chunks = 0;
+
 function serialize(obj = {}, fmt) {
   return JSON.stringify(obj, (k, v) => typeof v == 'bigint' ? v.toString() : v, fmt)
 }

src/clientTest.js

@@ -1,20 +1,42 @@
 // process.env.DEBUG = 'minecraft-protocol raknet'
 const { Client } = require('./client')
-
+const fs = require('fs')
 // console.log = () => 
 
 async function test() {
-    const client = new Client({
-        hostname: '127.0.0.1',
-        port: 19132
+  const client = new Client({
+    hostname: '127.0.0.1',
+    port: 19132
+  })
+
+  client.once('resource_packs_info', (packet) => {
+    client.write('resource_pack_client_response', {
+      response_status: 'completed',
+      resourcepackids: []
     })
-    
-    client.once('resource_packs_info', (packet) => {
-        client.write('resource_pack_client_response', {
-            response_status: 'completed',
-            resourcepackids: []
-        })
+
+    client.once('resource_pack_stack', (stack) => {
+      client.write('resource_pack_client_response', {
+        response_status: 'completed',
+        resourcepackids: []
+      })
     })
+
+    // client.once('resource_packs_info', (packet) => {
+    //   client.write('resource_pack_client_response', {
+    //     response_status: 'completed',
+    //     resourcepackids: []
+    //   })
+    // })
+  })
+
+
+
+  // var read = 0;
+  // client.on('level_chunk', (packet) => {
+  //   read++
+  //   fs.writeFileSync(`level_chunk-${read}.json`, JSON.stringify(packet, null, 2))
+  // })
 }
 
 test()

src/connection.js

@@ -2,8 +2,8 @@ const BinaryStream = require('@jsprismarine/jsbinaryutils').default
 const BatchPacket = require('./datatypes/BatchPacket')
 const cipher = require('./transforms/encryption')
 const { EventEmitter } = require('events')
-const EncapsulatedPacket = require('@jsprismarine/raknet/protocol/encapsulated_packet')
-
+const EncapsulatedPacket = require('jsp-raknet/protocol/encapsulated_packet')
+const debug = require('debug')('minecraft-protocol')
 
 class Connection extends EventEmitter {
   startEncryption(iv) {
@@ -15,8 +15,10 @@ class Connection extends EventEmitter {
 
   write(name, params) { // TODO: Batch
     console.log('Need to encode', name, params)
+    // console.log('<-', name)
     const batch = new BatchPacket()
     const packet = this.serializer.createPacketBuffer({ name, params })
+    console.log('Sending buf', packet.toString('hex'))
     batch.addEncodedPacket(packet)
 
     if (this.encryptionEnabled) {
@@ -45,6 +47,19 @@ class Connection extends EventEmitter {
     }
   }
 
+  /**
+   * Sends a MCPE packet buffer
+   */
+  sendBuffer(buffer) {
+    const batch = new BatchPacket()
+    batch.addEncodedPacket(buffer)
+    if (this.encryptionEnabled) {
+      this.sendEncryptedBatch(batch)
+    } else {
+      this.sendDecryptedBatch(batch)
+    }
+  }
+
   sendDecryptedBatch(batch) {
     const buf = batch.encode()
     // send to raknet
@@ -53,10 +68,11 @@ class Connection extends EventEmitter {
 
   sendEncryptedBatch(batch) {
     const buf = batch.stream.getBuffer()
-    console.log('Sending encrypted batch', batch)
+    debug('Sending encrypted batch', batch)
     this.encrypt(buf)
   }
 
+  // TODO: Rename this to sendEncapsulated
   sendMCPE(buffer, immediate) {
     if (this.worker) {
       console.log('-> buf', buffer)