Basic implementation of first login handshake

lib/server/packets.dart

@@ -0,0 +1,165 @@
+import 'dart:convert';
+
+import 'package:bugvault/server/main.dart';
+import 'package:bugvault/users/User.dart';
+import 'package:libac_dart/nbt/Tag.dart';
+import 'package:libac_dart/nbt/impl/CompoundTag.dart';
+import 'package:libac_dart/nbt/impl/IntTag.dart';
+import 'package:libac_dart/nbt/impl/StringTag.dart';
+import 'package:libac_dart/packets/packets.dart';
+
+class C2SPacketLogin implements IPacket {
+  String username = "";
+
+  @override
+  void decodeJson(String params) {
+    fromJson(json.decode(params));
+  }
+
+  @override
+  void decodeTag(Tag tag) {
+    CompoundTag ct = tag.asCompoundTag();
+    username = ct.get("user")?.asString() ?? "";
+  }
+
+  @override
+  NetworkDirection direction() {
+    return NetworkDirection.ClientToServer;
+  }
+
+  @override
+  String encodeJson() {
+    return json.encode(toJson());
+  }
+
+  @override
+  Tag encodeTag() {
+    CompoundTag ct = CompoundTag();
+    ct.put("user", StringTag.valueOf(username));
+
+    return ct;
+  }
+
+  @override
+  void fromJson(Map<String, dynamic> js) {
+    username = js['user'] as String;
+  }
+
+  @override
+  String getChannelID() {
+    return "BVPKTLOGIN";
+  }
+
+  @override
+  Future<void> handleClientPacket() async {
+    return;
+  }
+
+  @override
+  Future<PacketResponse> handleServerPacket() async {
+    S2CResponse response = S2CResponse();
+    S2CLoginReply loginReply = S2CLoginReply();
+    loginReply.username = username;
+
+    // Check if the user exists
+    DBUser? user = BugVaultServer.TryGetUser(username);
+    if (user == null && username != "") {
+      loginReply.g_ixLoginState |= LoginStates.NOT_FOUND;
+      loginReply.g_ixLoginState |= LoginStates.PROVIDE_EMAIL;
+    }
+
+    if (user != null) {
+      // Tell the user to send their TOTP Code
+      loginReply.g_ixLoginState |= LoginStates.FOUND;
+      loginReply.g_ixLoginState |= LoginStates.REQUIRE_MFA;
+    }
+
+    if (username == "") {
+      if (BugVaultServer.g_bAllowAnonymousLogin) {
+        loginReply.g_ixLoginState = LoginStates.LOGGED_IN;
+      } else {
+        loginReply.g_ixLoginState = LoginStates.ANONYMOUS_NOT_ALLOWED;
+      }
+    }
+
+    response.contents = loginReply.encodeTag().asCompoundTag();
+    return PacketResponse(replyDataTag: response.encodeTag().asCompoundTag());
+  }
+
+  @override
+  Map<String, dynamic> toJson() {
+    return {"user": username};
+  }
+}
+
+class LoginStates {
+  static const NOT_FOUND = 1;
+  static const FOUND = 2;
+  static const REQUIRE_MFA = 4;
+  static const PROVIDE_EMAIL = 8;
+  static const REQUIRE_EMAIL_CODE = 16;
+  static const LOGGED_IN = 32;
+  static const ANONYMOUS_NOT_ALLOWED = 64;
+}
+
+class S2CLoginReply implements IPacket {
+  String username = "";
+  int g_ixLoginState = 0;
+
+  @override
+  void decodeJson(String params) {
+    return fromJson(json.decode(params));
+  }
+
+  @override
+  void decodeTag(Tag tag) {
+    CompoundTag ct = tag.asCompoundTag();
+    username = ct.get("user")?.asString() ?? "";
+    g_ixLoginState = ct.get("state")?.asInt() ?? 0;
+  }
+
+  @override
+  NetworkDirection direction() {
+    return NetworkDirection.ServerToClient;
+  }
+
+  @override
+  String encodeJson() {
+    return json.encode(toJson());
+  }
+
+  @override
+  Tag encodeTag() {
+    CompoundTag ct = CompoundTag();
+    ct.put("user", StringTag.valueOf(username));
+    ct.put("state", IntTag.valueOf(g_ixLoginState));
+
+    return ct;
+  }
+
+  @override
+  void fromJson(Map<String, dynamic> js) {
+    username = js['user'] as String;
+    g_ixLoginState = js['state'] as int;
+  }
+
+  @override
+  String getChannelID() {
+    return "BVSPKTLOGINREPLY";
+  }
+
+  @override
+  Future<void> handleClientPacket() async {
+    // do handling stuff
+  }
+
+  @override
+  Future<PacketResponse> handleServerPacket() async {
+    throw UnimplementedError(); // Client side only, so this never gets invoked.
+  }
+
+  @override
+  Map<String, dynamic> toJson() {
+    return {"user": username, "state": g_ixLoginState};
+  }
+}