Flutter隐私保护插件tor的使用

foundation-Devices/tor 是一个多平台的Flutter插件，用于管理Tor代理。基于 arti 项目。本文将详细介绍如何在Flutter项目中使用该插件，并提供一个完整的示例demo。

开始之前

安装Rust

请确保安装了Rust工具链，建议使用 rustup 而不是 homebrew 进行安装。

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

安装cargo-ndk

cargo install cargo-ndk

Cargokit

Cargokit用于构建项目，只需运行 flutter run 或者在Android Studio或VS Code中运行（未测试）。

更新Cargokit时，可以使用以下命令：

git subtree pull --prefix cargokit https://github.com/irondash/cargokit.git main --squash

开发

为了重新生成Dart绑定，请运行：

just generate

示例应用

在 example 目录下运行 flutter run 来启动示例应用。具体使用方法请参考 example/lib/main.dart 文件。

示例代码

以下是一个完整的示例代码，展示如何在Flutter应用中使用Tor插件。

// SPDX-FileCopyrightText: 2023 Foundation Devices Inc.
// SPDX-FileCopyrightText: 2024 Foundation Devices Inc.
//
// SPDX-License-Identifier: MIT

import 'dart:async';
import 'dart:convert';
import 'dart:io';

import 'package:flutter/material.dart';
import 'package:socks5_proxy/socks_client.dart'; // Just for example; can use any socks5 proxy package, pick your favorite.
import 'package:tor/tor.dart';
import 'package:tor/socks_socket.dart'; // For socket connections

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      home: Home(),
    );
  }
}

class Home extends StatefulWidget {
  const Home({super.key});

  @override
  State<Home> createState() => _MyAppState();
}

class _MyAppState extends State<Home> {
  bool torStarted = false;
  final hostController = TextEditingController(text: 'https://icanhazip.com/');

  Future<void> startTor() async {
    await Tor.init();
    await Tor.instance.start();
    setState(() {
      torStarted = Tor.instance.started;
    });
    print('Done awaiting; tor should be running');
  }

  @override
  void dispose() {
    hostController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    const spacerSmall = SizedBox(height: 10);
    return Scaffold(
      appBar: AppBar(
        title: const Text('Tor example'),
      ),
      body: SingleChildScrollView(
        child: Container(
          padding: const EdgeInsets.all(10),
          child: Column(
            children: [
              Row(
                children: [
                  TextButton(
                    onPressed: torStarted
                        ? null
                        : () async {
                            unawaited(
                              showDialog(
                                barrierDismissible: false,
                                context: context,
                                builder: (_) => const Dialog(
                                  child: Padding(
                                    padding: EdgeInsets.all(20.0),
                                    child: Text("Starting tor..."),
                                  ),
                                ),
                              ),
                            );

                            final time = DateTime.now();
                            print("NOW: $time");
                            await startTor();
                            print("Starting tor took "
                                "${DateTime.now().difference(time).inSeconds} "
                                "seconds. Proxy running on port ${Tor.instance.port}");

                            if (mounted) {
                              Navigator.of(context).pop();
                            }
                          },
                    child: const Text("Start"),
                  ),
                  TextButton(
                    onPressed: !torStarted
                        ? null
                        : () async {
                            await Tor.instance.stop();
                            setState(() {
                              torStarted = false;
                            });
                          },
                    child: const Text("Stop"),
                  ),
                ],
              ),
              Row(
                children: [
                  Expanded(
                    child: TextField(
                      controller: hostController,
                      decoration: const InputDecoration(
                        border: OutlineInputBorder(),
                        hintText: 'Host to request',
                      ),
                    ),
                  ),
                  spacerSmall,
                  TextButton(
                    onPressed: torStarted
                        ? () async {
                            final client = HttpClient();
                            SocksTCPClient.assignToHttpClient(client, [
                              ProxySettings(InternetAddress.loopbackIPv4,
                                  Tor.instance.port, password: null),
                            ]);

                            final url = Uri.parse(hostController.text);
                            final request = await client.getUrl(url);
                            final response = await request.close();
                            var responseString =
                                await utf8.decodeStream(response);
                            print(responseString);

                            client.close();
                          }
                        : null,
                    child: const Text("Make proxied request"),
                  ),
                ],
              ),
              spacerSmall,
              TextButton(
                onPressed: torStarted
                    ? () async {
                        var socksSocket = await SOCKSSocket.create(
                          proxyHost: InternetAddress.loopbackIPv4.address,
                          proxyPort: Tor.instance.port,
                          sslEnabled: true,
                        );

                        await socksSocket.connect();
                        await socksSocket.connectTo('bitcoin.stackwallet.com', 50002);
                        await socksSocket.sendServerFeaturesCommand();
                        await socksSocket.close();
                      }
                    : null,
                child: const Text(
                  "Connect to bitcoin.stackwallet.com:50002 (SSL) via socks socket",
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}

通过上述代码，您可以在Flutter应用中集成Tor插件，实现隐私保护功能。希望这个示例能够帮助您更好地理解和使用Tor插件。