add plugins

pkg/plugin/builtin/http.go

@@ -0,0 +1,116 @@
+package builtin
+
+import (
+	"bufio"
+	"io"
+	"net"
+	"net/http"
+	"strings"
+
+	"github.com/gotunnel/pkg/plugin"
+)
+
+// HTTPPlugin 将现有 HTTP 代理实现封装为 plugin
+type HTTPPlugin struct {
+	config map[string]string
+}
+
+// NewHTTPPlugin 创建 HTTP plugin
+func NewHTTPPlugin() *HTTPPlugin {
+	return &HTTPPlugin{}
+}
+
+// Metadata 返回 plugin 信息
+func (p *HTTPPlugin) Metadata() plugin.PluginMetadata {
+	return plugin.PluginMetadata{
+		Name:        "http",
+		Version:     "1.0.0",
+		Type:        plugin.PluginTypeProxy,
+		Source:      plugin.PluginSourceBuiltin,
+		Description: "HTTP/HTTPS proxy protocol handler",
+		Author:      "GoTunnel",
+		Capabilities: []string{
+			"dial", "read", "write", "close",
+		},
+	}
+}
+
+// Init 初始化 plugin
+func (p *HTTPPlugin) Init(config map[string]string) error {
+	p.config = config
+	return nil
+}
+
+// HandleConn 处理 HTTP 代理连接
+func (p *HTTPPlugin) HandleConn(conn net.Conn, dialer plugin.Dialer) error {
+	defer conn.Close()
+
+	reader := bufio.NewReader(conn)
+	req, err := http.ReadRequest(reader)
+	if err != nil {
+		return err
+	}
+
+	if req.Method == http.MethodConnect {
+		return p.handleConnect(conn, req, dialer)
+	}
+	return p.handleHTTP(conn, req, dialer)
+}
+
+// Close 释放资源
+func (p *HTTPPlugin) Close() error {
+	return nil
+}
+
+// handleConnect 处理 CONNECT 方法 (HTTPS)
+func (p *HTTPPlugin) handleConnect(conn net.Conn, req *http.Request, dialer plugin.Dialer) error {
+	target := req.Host
+	if !strings.Contains(target, ":") {
+		target = target + ":443"
+	}
+
+	remote, err := dialer.Dial("tcp", target)
+	if err != nil {
+		conn.Write([]byte("HTTP/1.1 502 Bad Gateway\r\n\r\n"))
+		return err
+	}
+	defer remote.Close()
+
+	conn.Write([]byte("HTTP/1.1 200 Connection Established\r\n\r\n"))
+
+	go io.Copy(remote, conn)
+	io.Copy(conn, remote)
+	return nil
+}
+
+// handleHTTP 处理普通 HTTP 请求
+func (p *HTTPPlugin) handleHTTP(conn net.Conn, req *http.Request, dialer plugin.Dialer) error {
+	target := req.Host
+	if !strings.Contains(target, ":") {
+		target = target + ":80"
+	}
+
+	remote, err := dialer.Dial("tcp", target)
+	if err != nil {
+		conn.Write([]byte("HTTP/1.1 502 Bad Gateway\r\n\r\n"))
+		return err
+	}
+	defer remote.Close()
+
+	// 修改请求路径为相对路径
+	req.URL.Scheme = ""
+	req.URL.Host = ""
+	req.RequestURI = req.URL.Path
+	if req.URL.RawQuery != "" {
+		req.RequestURI += "?" + req.URL.RawQuery
+	}
+
+	// 发送请求到目标
+	if err := req.Write(remote); err != nil {
+		return err
+	}
+
+	// 转发响应
+	_, err = io.Copy(conn, remote)
+	return err
+}