From 1bf47f4dbf2870db0102c154916c87fa595cf5a9 Mon Sep 17 00:00:00 2001
From: SilverFire - Dmitry Naumenko <d.naumenko.a@gmail.com>
Date: Thu, 21 Apr 2022 17:33:45 +0300
Subject: [PATCH] Add X-Forwarded-Host header passing

---
 nginx.tmpl                     |  8 ++++++++
 test/test_headers/test_http.py | 12 ++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/nginx.tmpl b/nginx.tmpl
index 3ac52f8..70123c6 100644
--- a/nginx.tmpl
+++ b/nginx.tmpl
@@ -79,6 +79,13 @@ map $http_x_forwarded_port $proxy_x_forwarded_port {
   ''      $server_port;
 }
 
+# If we receive X-Forwarded-Host, pass it through; otherwise, pass along the
+# host the client connected to
+map $http_x_forwarded_host $proxy_x_forwarded_host {
+  default $http_x_forwarded_host;
+  ''      $http_host;
+}
+
 # If we receive Upgrade, set Connection to "upgrade"; otherwise, delete any
 # Connection header that may have been passed to this server
 map $http_upgrade $proxy_connection {
@@ -127,6 +134,7 @@ proxy_set_header Upgrade $http_upgrade;
 proxy_set_header Connection $proxy_connection;
 proxy_set_header X-Real-IP $remote_addr;
 proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+proxy_set_header X-Forwarded-Host $proxy_x_forwarded_host;
 proxy_set_header X-Forwarded-Proto $proxy_x_forwarded_proto;
 proxy_set_header X-Forwarded-Ssl $proxy_x_forwarded_ssl;
 proxy_set_header X-Forwarded-Port $proxy_x_forwarded_port;
diff --git a/test/test_headers/test_http.py b/test/test_headers/test_http.py
index 2799262..0b767b3 100644
--- a/test/test_headers/test_http.py
+++ b/test/test_headers/test_http.py
@@ -57,6 +57,18 @@ def test_X_Forwarded_Ssl_is_overwritten(docker_compose, nginxproxy):
     assert r.status_code == 200
     assert "X-Forwarded-Ssl: off\n" in r.text
 
+##### Testing the handling of X-Forwarded-Host #####
+
+def test_X_Forwarded_Host_is_generated(docker_compose, nginxproxy):
+    r = nginxproxy.get("http://web.nginx-proxy.tld/headers")
+    assert r.status_code == 200
+    assert "X-Forwarded-Host: web.nginx-proxy.tld\n" in r.text
+
+def test_X_Forwarded_Host_is_overwritten(docker_compose, nginxproxy):
+    r = nginxproxy.get("http://web.nginx-proxy.tld/headers", headers={'X-Forwarded-Host': 'foo.bar.baz'})
+    assert r.status_code == 200
+    assert "X-Forwarded-Host: web.nginx-proxy.tld\n" in r.text
+
 
 ##### Other headers