From 52d5c9e25b83cad98ccca7edf0bdda32dfc1c351 Mon Sep 17 00:00:00 2001
From: Kevin Crawley <kevin@nashgo.org>
Date: Tue, 26 Jan 2021 23:14:16 -0600
Subject: [PATCH] initial commit for https2https plugin (#2201)

---
 README.md                        |   4 +-
 conf/frpc_full.ini               |  10 +++
 pkg/plugin/client/https2https.go | 138 +++++++++++++++++++++++++++++++
 3 files changed, 151 insertions(+), 1 deletion(-)
 create mode 100644 pkg/plugin/client/https2https.go

diff --git a/README.md b/README.md
index 2ad2dcd..45a20fd 100644
--- a/README.md
+++ b/README.md
@@ -258,7 +258,9 @@ Configure `frps` same as above.
 
 2. Visit `http://x.x.x.x:6000/static/` from your browser and specify correct user and password to view files in `/tmp/files` on the `frpc` machine.
 
-### Enable HTTPS for local HTTP service
+### Enable HTTPS for local HTTP(S) service
+
+You may substitute `https2https` for the plugin, and point the `plugin_local_addr` to a HTTPS endpoint.
 
 1. Start `frpc` with configuration:
 
diff --git a/conf/frpc_full.ini b/conf/frpc_full.ini
index 1b5c700..12b92b6 100644
--- a/conf/frpc_full.ini
+++ b/conf/frpc_full.ini
@@ -246,6 +246,16 @@ plugin_key_path = ./server.key
 plugin_host_header_rewrite = 127.0.0.1
 plugin_header_X-From-Where = frp
 
+[plugin_https2https]
+type = https
+custom_domains = test.yourdomain.com
+plugin = https2https
+plugin_local_addr = 127.0.0.1:443
+plugin_crt_path = ./server.crt
+plugin_key_path = ./server.key
+plugin_host_header_rewrite = 127.0.0.1
+plugin_header_X-From-Where = frp
+
 [plugin_http2https]
 type = http
 custom_domains = test.yourdomain.com
diff --git a/pkg/plugin/client/https2https.go b/pkg/plugin/client/https2https.go
new file mode 100644
index 0000000..159ed39
--- /dev/null
+++ b/pkg/plugin/client/https2https.go
@@ -0,0 +1,138 @@
+// Copyright 2019 fatedier, fatedier@gmail.com
+//
+// 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
+//
+//     http://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.
+
+package plugin
+
+import (
+	"crypto/tls"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"net/http/httputil"
+	"strings"
+
+	frpNet "github.com/fatedier/frp/pkg/util/net"
+)
+
+const PluginHTTPS2HTTPS = "https2https"
+
+func init() {
+	Register(PluginHTTPS2HTTPS, NewHTTPS2HTTPSPlugin)
+}
+
+type HTTPS2HTTPSPlugin struct {
+	crtPath           string
+	keyPath           string
+	hostHeaderRewrite string
+	localAddr         string
+	headers           map[string]string
+
+	l *Listener
+	s *http.Server
+}
+
+func NewHTTPS2HTTPSPlugin(params map[string]string) (Plugin, error) {
+	crtPath := params["plugin_crt_path"]
+	keyPath := params["plugin_key_path"]
+	localAddr := params["plugin_local_addr"]
+	hostHeaderRewrite := params["plugin_host_header_rewrite"]
+	headers := make(map[string]string)
+	for k, v := range params {
+		if !strings.HasPrefix(k, "plugin_header_") {
+			continue
+		}
+		if k = strings.TrimPrefix(k, "plugin_header_"); k != "" {
+			headers[k] = v
+		}
+	}
+
+	if crtPath == "" {
+		return nil, fmt.Errorf("plugin_crt_path is required")
+	}
+	if keyPath == "" {
+		return nil, fmt.Errorf("plugin_key_path is required")
+	}
+	if localAddr == "" {
+		return nil, fmt.Errorf("plugin_local_addr is required")
+	}
+
+	listener := NewProxyListener()
+
+	p := &HTTPS2HTTPSPlugin{
+		crtPath:           crtPath,
+		keyPath:           keyPath,
+		localAddr:         localAddr,
+		hostHeaderRewrite: hostHeaderRewrite,
+		headers:           headers,
+		l:                 listener,
+	}
+
+	tr := &http.Transport{
+		TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
+	}
+
+	rp := &httputil.ReverseProxy{
+		Director: func(req *http.Request) {
+			req.URL.Scheme = "https"
+			req.URL.Host = p.localAddr
+			if p.hostHeaderRewrite != "" {
+				req.Host = p.hostHeaderRewrite
+			}
+			for k, v := range p.headers {
+				req.Header.Set(k, v)
+			}
+		},
+		Transport: tr,
+	}
+
+	p.s = &http.Server{
+		Handler: rp,
+	}
+
+	tlsConfig, err := p.genTLSConfig()
+	if err != nil {
+		return nil, fmt.Errorf("gen TLS config error: %v", err)
+	}
+	ln := tls.NewListener(listener, tlsConfig)
+
+	go p.s.Serve(ln)
+	return p, nil
+}
+
+func (p *HTTPS2HTTPSPlugin) genTLSConfig() (*tls.Config, error) {
+	cert, err := tls.LoadX509KeyPair(p.crtPath, p.keyPath)
+	if err != nil {
+		return nil, err
+	}
+
+	config := &tls.Config{Certificates: []tls.Certificate{cert}}
+	return config, nil
+}
+
+func (p *HTTPS2HTTPSPlugin) Handle(conn io.ReadWriteCloser, realConn net.Conn, extraBufToLocal []byte) {
+	wrapConn := frpNet.WrapReadWriteCloserToConn(conn, realConn)
+	p.l.PutConn(wrapConn)
+}
+
+func (p *HTTPS2HTTPSPlugin) Name() string {
+	return PluginHTTPS2HTTP
+}
+
+func (p *HTTPS2HTTPSPlugin) Close() error {
+	if err := p.s.Close(); err != nil {
+		return err
+	}
+	return nil
+}