From b51cca53470898bb3c278dcd8cf13bd0bfa22a18 Mon Sep 17 00:00:00 2001
From: cynic <cynic@mesh.kyun.li>
Date: Fri, 14 Jun 2024 05:25:27 +0000
Subject: [PATCH] check for ip in reverse proxy header

---
 cmd/whoami/main.go | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/cmd/whoami/main.go b/cmd/whoami/main.go
index 00ae846..2eb5fbf 100644
--- a/cmd/whoami/main.go
+++ b/cmd/whoami/main.go
@@ -20,8 +20,14 @@ func domainFromIP(target net.IP) string {
 
 // handle HTTP requests
 func handler(w http.ResponseWriter, r *http.Request) {
+	// get client's ip address
 	ip, port, err := net.SplitHostPort(r.RemoteAddr)
 	_, _ = port, err	
+	// check if we're behind a reverse proxy
+	xForwardedFor := r.Header.Get("X-Forwarded-For")
+	if xForwardedFor != "" {
+		ip = xForwardedFor
+	}
 	parsedIP := net.ParseIP(ip)
 	// return domain for IPv6 only
 	if parsedIP.To4() == nil {