fix: make sure that realIP is always set, even when not using CF

jramsgz · web-flow · commit 7cc3b67f1650 · 2023-04-07T13:46:34.000+02:00
diff --git a/real_ip.go b/real_ip.go
@@ -65,11 +65,17 @@ func (r *RealIPOverWriter) ServeHTTP(rw http.ResponseWriter, req *http.Request)
 		}
 	}
 
-	if realIP == "" {
+	// Use `Cf-Connecting-Ip` when available
+	if req.Header.Get(cfConnectingIP) != "" {
 		realIP = req.Header.Get(cfConnectingIP)
 		req.Header.Set(xForwardedFor, realIP)
 	}
 
+	// If it is not possible to determine the real IP, the connecting IP is used as a fallback.
+	if realIP == "" {
+		realIP = req.RemoteAddr;
+	}
+
 	req.Header.Set(xRealIP, realIP)
 
 	r.next.ServeHTTP(rw, req)

Original file line number	Diff line number	Diff line change
`@@ -65,11 +65,17 @@ func (r RealIPOverWriter) ServeHTTP(rw http.ResponseWriter, req http.Request)`
`65`	`65`	`}`
`66`	`66`	`}`
`67`	`67`
`68`		`- if realIP == "" {`
	`68`	+ // Use `Cf-Connecting-Ip` when available
	`69`	`+ if req.Header.Get(cfConnectingIP) != "" {`
`69`	`70`	`realIP = req.Header.Get(cfConnectingIP)`
`70`	`71`	`req.Header.Set(xForwardedFor, realIP)`
`71`	`72`	`}`
`72`	`73`
	`74`	`+ // If it is not possible to determine the real IP, the connecting IP is used as a fallback.`
	`75`	`+ if realIP == "" {`
	`76`	`+ realIP = req.RemoteAddr;`
	`77`	`+ }`
	`78`	`+`
`73`	`79`	`req.Header.Set(xRealIP, realIP)`
`74`	`80`
`75`	`81`	`r.next.ServeHTTP(rw, req)`