From 25dcf536c6f52fb6dc8df8486b8776720ea709df Mon Sep 17 00:00:00 2001
From: ginuerzh <ginuerzh@gmail.com>
Date: Wed, 31 Jan 2024 23:18:42 +0800
Subject: [PATCH] added url path rewrite for forwarder node

---
 config/config.go                  | 12 +++++++++---
 config/parsing/node/parse.go      |  9 +++++++++
 go.mod                            |  2 +-
 go.sum                            |  4 ++--
 handler/forward/local/handler.go  |  9 +++++++++
 handler/forward/remote/handler.go |  9 +++++++++
 6 files changed, 39 insertions(+), 6 deletions(-)

diff --git a/config/config.go b/config/config.go
index bb05bda..389bc95 100644
--- a/config/config.go
+++ b/config/config.go
@@ -364,10 +364,16 @@ type ForwardNodeConfig struct {
 	Metadata map[string]any `yaml:",omitempty" json:"metadata,omitempty"`
 }
 
+type HTTPURLRewriteConfig struct {
+	Match       string
+	Replacement string
+}
+
 type HTTPNodeConfig struct {
-	Host   string            `yaml:",omitempty" json:"host,omitempty"`
-	Header map[string]string `yaml:",omitempty" json:"header,omitempty"`
-	Auth   *AuthConfig       `yaml:",omitempty" json:"auth,omitempty"`
+	Host    string                 `yaml:",omitempty" json:"host,omitempty"`
+	Header  map[string]string      `yaml:",omitempty" json:"header,omitempty"`
+	Auth    *AuthConfig            `yaml:",omitempty" json:"auth,omitempty"`
+	Rewrite []HTTPURLRewriteConfig `yaml:",omitempty" json:"rewrite,omitempty"`
 }
 
 type TLSNodeConfig struct {
diff --git a/config/parsing/node/parse.go b/config/parsing/node/parse.go
index 7f51e99..b1eb9c2 100644
--- a/config/parsing/node/parse.go
+++ b/config/parsing/node/parse.go
@@ -3,6 +3,7 @@ package node
 import (
 	"fmt"
 	"net"
+	"regexp"
 	"strings"
 	"time"
 
@@ -189,6 +190,14 @@ func ParseNode(hop string, cfg *config.NodeConfig, log logger.Logger) (*chain.No
 				})),
 			)
 		}
+		for _, v := range cfg.HTTP.Rewrite {
+			if pattern, _ := regexp.Compile(v.Match); pattern != nil {
+				settings.Rewrite = append(settings.Rewrite, chain.HTTPURLRewriteSetting{
+					Pattern:     pattern,
+					Replacement: v.Replacement,
+				})
+			}
+		}
 		opts = append(opts, chain.HTTPNodeOption(settings))
 	}
 	if cfg.TLS != nil {
diff --git a/go.mod b/go.mod
index f889440..d4e06ab 100644
--- a/go.mod
+++ b/go.mod
@@ -7,7 +7,7 @@ require (
 	github.com/asaskevich/govalidator v0.0.0-20210307081110-f21760c49a8d
 	github.com/gin-contrib/cors v1.5.0
 	github.com/gin-gonic/gin v1.9.1
-	github.com/go-gost/core v0.0.0-20240127130604-04314fa08476
+	github.com/go-gost/core v0.0.0-20240131151724-a06608ccafbf
 	github.com/go-gost/gosocks4 v0.0.1
 	github.com/go-gost/gosocks5 v0.4.0
 	github.com/go-gost/plugin v0.0.0-20240103125338-9c84e29cb81a
diff --git a/go.sum b/go.sum
index 25aa306..d08bdff 100644
--- a/go.sum
+++ b/go.sum
@@ -49,8 +49,8 @@ github.com/gin-contrib/sse v0.1.0 h1:Y/yl/+YNO8GZSjAhjMsSuLt29uWRFHdHYUb5lYOV9qE
 github.com/gin-contrib/sse v0.1.0/go.mod h1:RHrZQHXnP2xjPF+u1gW/2HnVO7nvIa9PG3Gm+fLHvGI=
 github.com/gin-gonic/gin v1.9.1 h1:4idEAncQnU5cB7BeOkPtxjfCSye0AAm1R0RVIqJ+Jmg=
 github.com/gin-gonic/gin v1.9.1/go.mod h1:hPrL7YrpYKXt5YId3A/Tnip5kqbEAP+KLuI3SUcPTeU=
-github.com/go-gost/core v0.0.0-20240127130604-04314fa08476 h1:4TA4ErfFw2CsVv5K5oqqYpUn68aZFrV+ONb4aGPJ1QQ=
-github.com/go-gost/core v0.0.0-20240127130604-04314fa08476/go.mod h1:ndkgWVYRLwupVaFFWv8ML1Nr8tD3xhHK245PLpUDg4E=
+github.com/go-gost/core v0.0.0-20240131151724-a06608ccafbf h1:akQ96Ibm+P7IftDluZPoMCzBzbLR/TjFu8Wpjy3H7hM=
+github.com/go-gost/core v0.0.0-20240131151724-a06608ccafbf/go.mod h1:ndkgWVYRLwupVaFFWv8ML1Nr8tD3xhHK245PLpUDg4E=
 github.com/go-gost/gosocks4 v0.0.1 h1:+k1sec8HlELuQV7rWftIkmy8UijzUt2I6t+iMPlGB2s=
 github.com/go-gost/gosocks4 v0.0.1/go.mod h1:3B6L47HbU/qugDg4JnoFPHgJXE43Inz8Bah1QaN9qCc=
 github.com/go-gost/gosocks5 v0.4.0 h1:EIrOEkpJez4gwHrMa33frA+hHXJyevjp47thpMQsJzI=
diff --git a/handler/forward/local/handler.go b/handler/forward/local/handler.go
index 5f7c960..0d8f9cb 100644
--- a/handler/forward/local/handler.go
+++ b/handler/forward/local/handler.go
@@ -266,6 +266,15 @@ func (h *forwardHandler) handleHTTP(ctx context.Context, rw io.ReadWriter, remot
 				for k, v := range httpSettings.Header {
 					req.Header.Set(k, v)
 				}
+
+				for _, re := range httpSettings.Rewrite {
+					if re.Pattern.MatchString(req.URL.Path) {
+						if s := re.Pattern.ReplaceAllString(req.URL.Path, re.Replacement); s != "" {
+							req.URL.Path = s
+							break
+						}
+					}
+				}
 			}
 
 			cc, err = h.router.Dial(ctx, "tcp", target.Addr)
diff --git a/handler/forward/remote/handler.go b/handler/forward/remote/handler.go
index dbd945d..c00da9f 100644
--- a/handler/forward/remote/handler.go
+++ b/handler/forward/remote/handler.go
@@ -266,6 +266,15 @@ func (h *forwardHandler) handleHTTP(ctx context.Context, rw io.ReadWriter, remot
 				for k, v := range httpSettings.Header {
 					req.Header.Set(k, v)
 				}
+
+				for _, re := range httpSettings.Rewrite {
+					if re.Pattern.MatchString(req.URL.Path) {
+						if s := re.Pattern.ReplaceAllString(req.URL.Path, re.Replacement); s != "" {
+							req.URL.Path = s
+							break
+						}
+					}
+				}
 			}
 
 			cc, err = h.router.Dial(ctx, "tcp", target.Addr)