Files
proxypin/lib/network/handler.dart
2023-10-19 01:36:03 +08:00

322 lines
11 KiB
Dart

/*
* Copyright 2023 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import 'dart:async';
import 'dart:convert';
import 'dart:io';
import 'package:network_proxy/network/host_port.dart';
import 'package:network_proxy/network/http/http.dart';
import 'package:network_proxy/network/http/http_headers.dart';
import 'package:network_proxy/network/util/attribute_keys.dart';
import 'package:network_proxy/network/util/file_read.dart';
import 'package:network_proxy/network/util/host_filter.dart';
import 'package:network_proxy/network/util/request_rewrite.dart';
import 'package:network_proxy/network/util/script_manager.dart';
import 'package:network_proxy/utils/ip.dart';
import 'channel.dart';
import 'http/codec.dart';
import 'http_client.dart';
///请求和响应事件监听
abstract class EventListener {
void onRequest(Channel channel, HttpRequest request);
void onResponse(Channel channel, HttpResponse response);
}
/// http请求处理器
class HttpChannelHandler extends ChannelHandler<HttpRequest> {
EventListener? listener;
RequestRewrites? requestRewrites;
HttpChannelHandler({this.listener, this.requestRewrites});
@override
void channelRead(Channel channel, HttpRequest msg) async {
channel.putAttribute(AttributeKeys.request, msg);
if (msg.uri == 'http://proxy.pin/ssl' || msg.requestUrl == 'http://127.0.0.1:${channel.socket.port}/ssl') {
_crtDownload(channel, msg);
return;
}
//请求本服务
if ((await localIps()).contains(msg.hostAndPort?.host) && msg.hostAndPort?.port == channel.socket.port) {
localRequest(msg, channel);
return;
}
//转发请求
forward(channel, msg).catchError((error, trace) {
exceptionCaught(channel, error, trace: trace);
});
}
@override
void exceptionCaught(Channel channel, error, {StackTrace? trace}) {
super.exceptionCaught(channel, error, trace: trace);
_exceptionHandler(channel, channel.getAttribute(AttributeKeys.request), error);
}
@override
void channelInactive(Channel channel) {
Channel? remoteChannel = channel.getAttribute(channel.id);
remoteChannel?.close();
// log.i("[${channel.id}] close ${channel.error}");
}
//请求本服务
localRequest(HttpRequest msg, Channel channel) async {
//获取配置
if (msg.path() == '/config') {
var response = HttpResponse(HttpStatus.ok, protocolVersion: msg.protocolVersion);
var body = {
"requestRewrites": requestRewrites?.toJson(),
'whitelist': HostFilter.whitelist.toJson(),
'blacklist': HostFilter.blacklist.toJson(),
};
response.body = utf8.encode(json.encode(body));
channel.writeAndClose(response);
return;
}
var response = HttpResponse(HttpStatus.ok, protocolVersion: msg.protocolVersion);
response.body = utf8.encode('pong');
response.headers.set("os", Platform.operatingSystem);
response.headers.set("hostname", Platform.isAndroid ? Platform.operatingSystem : Platform.localHostname);
channel.writeAndClose(response);
}
/// 转发请求
Future<void> forward(Channel channel, HttpRequest httpRequest) async {
// log.i("[${channel.id}] ${httpRequest.method.name} ${httpRequest.requestUrl}");
if (channel.error != null) {
_exceptionHandler(channel, httpRequest, channel.error);
return;
}
//获取远程连接
Channel remoteChannel;
try {
remoteChannel = await _getRemoteChannel(channel, httpRequest);
remoteChannel.putAttribute(remoteChannel.id, channel);
} catch (error) {
channel.error = error; //记录异常
//https代理新建连接请求
if (httpRequest.method == HttpMethod.connect) {
await channel.write(
HttpResponse(HttpStatus.ok.reason('Connection established'), protocolVersion: httpRequest.protocolVersion));
}
return;
}
//实现抓包代理转发
if (httpRequest.method != HttpMethod.connect) {
// log.i("[${channel.id}] ${httpRequest.method.name} ${httpRequest.requestUrl}");
if (HostFilter.filter(httpRequest.hostAndPort?.host)) {
await remoteChannel.write(httpRequest);
return;
}
//脚本替换
var scriptManager = await ScriptManager.instance;
httpRequest = await scriptManager.runScript(httpRequest);
//替换请求体
rewriteBody(httpRequest);
listener?.onRequest(channel, httpRequest);
//重定向
var redirectRewrite =
requestRewrites?.findRequestRewrite(httpRequest.hostAndPort?.host, httpRequest.path(), RuleType.redirect);
if (redirectRewrite?.redirectUrl?.isNotEmpty == true) {
var proxyHandler = HttpResponseProxyHandler(channel, listener: listener, requestRewrites: requestRewrites);
httpRequest.uri = redirectRewrite!.redirectUrl!;
httpRequest.headers.host = Uri.parse(redirectRewrite.redirectUrl!).host;
var redirectChannel = await HttpClients.connect(Uri.parse(redirectRewrite.redirectUrl!), proxyHandler);
await redirectChannel.write(httpRequest);
return;
}
await remoteChannel.write(httpRequest);
}
}
//替换请求体
rewriteBody(HttpRequest httpRequest) {
var rewrite = requestRewrites?.findRequestRewrite(httpRequest.hostAndPort?.host, httpRequest.path(), RuleType.body);
if (rewrite?.requestBody?.isNotEmpty == true) {
httpRequest.body = utf8.encode(rewrite!.requestBody!);
}
if (rewrite?.queryParam?.isNotEmpty == true) {
httpRequest.uri = httpRequest.requestUri?.replace(query: rewrite!.queryParam!).toString() ?? httpRequest.uri;
}
}
/// 下载证书
void _crtDownload(Channel channel, HttpRequest request) async {
const String fileMimeType = 'application/x-x509-ca-cert';
var response = HttpResponse(HttpStatus.ok);
response.headers.set(HttpHeaders.CONTENT_TYPE, fileMimeType);
response.headers.set("Content-Disposition", 'inline;filename=ProxyPinCA.crt');
response.headers.set("Connection", 'close');
var body = await FileRead.read('assets/certs/ca.crt');
response.headers.set("Content-Length", body.lengthInBytes.toString());
if (request.method == HttpMethod.head) {
channel.writeAndClose(response);
return;
}
response.body = body.buffer.asUint8List();
channel.writeAndClose(response);
}
/// 获取远程连接
Future<Channel> _getRemoteChannel(Channel clientChannel, HttpRequest httpRequest) async {
String clientId = clientChannel.id;
//客户端连接 作为缓存
Channel? remoteChannel = clientChannel.getAttribute(clientId);
if (remoteChannel != null) {
return remoteChannel;
}
var hostAndPort = getHostAndPort(httpRequest);
clientChannel.putAttribute(AttributeKeys.host, hostAndPort);
var proxyHandler = HttpResponseProxyHandler(clientChannel, listener: listener, requestRewrites: requestRewrites);
//远程转发
HostAndPort? remote = clientChannel.getAttribute(AttributeKeys.remote);
//外部代理
ProxyInfo? proxyInfo = clientChannel.getAttribute(AttributeKeys.proxyInfo);
if (remote != null || proxyInfo != null) {
HostAndPort connectHost = remote ?? HostAndPort.host(proxyInfo!.host, proxyInfo.port!);
var proxyChannel = await HttpClients.startConnect(connectHost, proxyHandler);
clientChannel.putAttribute(clientId, proxyChannel);
proxyChannel.write(httpRequest);
return proxyChannel;
}
var proxyChannel = await HttpClients.startConnect(hostAndPort, proxyHandler);
clientChannel.putAttribute(clientId, proxyChannel);
//https代理新建连接请求
if (httpRequest.method == HttpMethod.connect) {
await clientChannel.write(
HttpResponse(HttpStatus.ok.reason('Connection established'), protocolVersion: httpRequest.protocolVersion));
}
return proxyChannel;
}
/// 异常处理
_exceptionHandler(Channel channel, HttpRequest? request, error) {
HostAndPort? hostAndPort = channel.getAttribute(AttributeKeys.host);
hostAndPort ??= HostAndPort.host(scheme: HostAndPort.httpScheme, channel.remoteAddress.host, channel.remotePort);
String message = error.toString();
HttpStatus status = HttpStatus(-1, message);
if (error is HandshakeException) {
status = HttpStatus(-2, 'SSL握手失败');
} else if (error is ParserException) {
status = HttpStatus(-3, error.message);
} else if (error is SocketException) {
status = HttpStatus(-4, error.message);
} else if (error is SignalException) {
status.reason('执行脚本异常');
}
request ??= HttpRequest(HttpMethod.connect, hostAndPort.domain)
..body = message.codeUnits
..headers.contentLength = message.codeUnits.length
..hostAndPort = hostAndPort;
request.response = HttpResponse(status)
..headers.contentType = 'text/plain'
..headers.contentLength = message.codeUnits.length
..body = message.codeUnits;
listener?.onRequest(channel, request);
listener?.onResponse(channel, request.response!);
}
}
/// http响应代理
class HttpResponseProxyHandler extends ChannelHandler<HttpResponse> {
//客户端的连接
final Channel clientChannel;
EventListener? listener;
RequestRewrites? requestRewrites;
HttpResponseProxyHandler(this.clientChannel, {this.listener, this.requestRewrites});
@override
void channelRead(Channel channel, HttpResponse msg) async {
msg.request = clientChannel.getAttribute(AttributeKeys.request);
msg.request?.response = msg;
//域名是否过滤
if (HostFilter.filter(msg.request?.hostAndPort?.host) || msg.request?.method == HttpMethod.connect) {
await clientChannel.write(msg);
return;
}
// log.i("[${clientChannel.id}] Response $msg");
//脚本替换
var scriptManager = await ScriptManager.instance;
try {
msg = await scriptManager.runResponseScript(msg);
} catch (e, t) {
msg.status = HttpStatus(-1, '执行脚本异常');
msg.body = "$e\n${msg.bodyAsString}".codeUnits;
log.e('[${clientChannel.id}] 执行脚本异常 ', error: e, stackTrace: t);
}
var replaceBody = requestRewrites?.findResponseReplaceWith(msg.request?.hostAndPort?.host, msg.request?.path());
if (replaceBody?.isNotEmpty == true) {
msg.body = utf8.encode(replaceBody!);
}
listener?.onResponse(clientChannel, msg);
//发送给客户端
await clientChannel.write(msg);
}
@override
void channelInactive(Channel channel) {
clientChannel.close();
}
}
class RelayHandler extends ChannelHandler<Object> {
final Channel remoteChannel;
RelayHandler(this.remoteChannel);
@override
void channelRead(Channel channel, Object msg) async {
//发送给客户端
remoteChannel.write(msg);
}
@override
void channelInactive(Channel channel) {
remoteChannel.close();
}
}