From 8f888cddac2ca88a7dccd73ee236dda1c88caa26 Mon Sep 17 00:00:00 2001
From: MrMelon54 <github@mrmelon54.com>
Date: Mon, 23 Oct 2023 12:31:27 +0100
Subject: [PATCH] First commit

---
 .gitignore       |  2 ++
 go.mod           |  3 +++
 host-rewriter.go | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 51 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 go.mod
 create mode 100644 host-rewriter.go

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..a1c6eea
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+.idea/
+host-rewriter
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..f64538c
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module github.com/MrMelon54/host-rewriter
+
+go 1.21.3
diff --git a/host-rewriter.go b/host-rewriter.go
new file mode 100644
index 0000000..5e9e4eb
--- /dev/null
+++ b/host-rewriter.go
@@ -0,0 +1,46 @@
+package main
+
+import (
+	"flag"
+	"log"
+	"net/http"
+	"net/http/httputil"
+	"net/url"
+	"time"
+)
+
+var listenFlag, targetFlag, hostFlag string
+
+func main() {
+	flag.StringVar(&listenFlag, "listen", ":8080", "Listen address")
+	flag.StringVar(&targetFlag, "target", "", "Set target URL to forward to")
+	flag.StringVar(&hostFlag, "host", "", "Set the host value")
+	flag.Parse()
+
+	target, err := url.Parse(targetFlag)
+	if err != nil {
+		log.Fatal("Failed to parse target URL:", err)
+	}
+
+	proxy := &httputil.ReverseProxy{
+		Rewrite: func(r *httputil.ProxyRequest) {
+			r.SetURL(target)
+			r.Out.Host = hostFlag
+		},
+	}
+	s := http.Server{
+		Addr:              listenFlag,
+		Handler:           proxy,
+		ReadTimeout:       150 * time.Second,
+		ReadHeaderTimeout: 150 * time.Second,
+		WriteTimeout:      150 * time.Second,
+		IdleTimeout:       150 * time.Second,
+		MaxHeaderBytes:    4096000,
+	}
+
+	log.Printf("Host Rewriter listening on %s\n", listenFlag)
+	log.Printf("Rewriting host to '%s' and forwarding to '%s'\n", hostFlag, targetFlag)
+	if err := s.ListenAndServe(); err != nil {
+		log.Fatal(err)
+	}
+}