Fix CalDAV/CardDAV URLs displayed in SOGo web interface when used behind a reverse proxy

data/conf/nginx/site.conf

@@ -1,4 +1,23 @@
 proxy_cache_path /tmp levels=1:2 keys_zone=sogo:10m inactive=24h  max_size=1g;
+
+# use the non-standard X-Forwarded-* headers for WebObjects
+map $http_x_forwarded_proto $maybe_real_scheme {
+  default $http_x_forwarded_proto;
+  ''      $scheme;
+}
+map $http_x_forwarded_port $maybe_real_port {
+  default $http_x_forwarded_port;
+  ''      $server_port;
+}
+map $realip_remote_addr $real_scheme {
+  default $scheme;
+  172.22.1.1 $maybe_real_scheme;
+}
+map $realip_remote_addr $real_port {
+  default $server_port;
+  172.22.1.1 $maybe_real_port;
+}
+
 server {
   include /etc/nginx/conf.d/listen_ssl.active;
   include /etc/nginx/mime.types;
@@ -34,7 +53,7 @@ server {
   real_ip_recursive on;
 
   location = /principals/ {
-    rewrite ^ $scheme://$host:$server_port/SOGo/dav;
+    rewrite ^ $real_scheme://$host:$real_port/SOGo/dav;
     allow all;
   }
 
@@ -100,8 +119,8 @@ server {
     proxy_set_header x-webobjects-server-protocol HTTP/1.0;
     proxy_set_header x-webobjects-remote-host $remote_addr;
     proxy_set_header x-webobjects-server-name $server_name;
-    proxy_set_header x-webobjects-server-url $scheme://$host:$server_port;
-    proxy_set_header x-webobjects-server-port $server_port;
+    proxy_set_header x-webobjects-server-url $real_scheme://$host:$real_port;
+    proxy_set_header x-webobjects-server-port $real_port;
     client_body_buffer_size 128k;
     client_max_body_size 100m;
   }
@@ -114,8 +133,8 @@ server {
     proxy_set_header x-webobjects-server-protocol HTTP/1.0;
     proxy_set_header x-webobjects-remote-host $remote_addr;
     proxy_set_header x-webobjects-server-name $server_name;
-    proxy_set_header x-webobjects-server-url $scheme://$host:$server_port;
-    proxy_set_header x-webobjects-server-port $server_port;
+    proxy_set_header x-webobjects-server-url $real_scheme://$host:$real_port;
+    proxy_set_header x-webobjects-server-port $real_port;
     client_body_buffer_size 128k;
     client_max_body_size 100m;
     break;
@@ -187,7 +206,7 @@ server {
   real_ip_recursive on;
 
   location = /principals/ {
-    rewrite ^ $scheme://$host:$server_port/SOGo/dav;
+    rewrite ^ $real_scheme://$host:$real_port/SOGo/dav;
     allow all;
   }
 
@@ -253,8 +272,8 @@ server {
     proxy_set_header x-webobjects-server-protocol HTTP/1.0;
     proxy_set_header x-webobjects-remote-host $remote_addr;
     proxy_set_header x-webobjects-server-name $server_name;
-    proxy_set_header x-webobjects-server-url $scheme://$host:$server_port;
-    proxy_set_header x-webobjects-server-port $server_port;
+    proxy_set_header x-webobjects-server-url $real_scheme://$host:$real_port;
+    proxy_set_header x-webobjects-server-port $real_port;
     client_body_buffer_size 128k;
     client_max_body_size 100m;
   }
@@ -267,8 +286,8 @@ server {
     proxy_set_header x-webobjects-server-protocol HTTP/1.0;
     proxy_set_header x-webobjects-remote-host $remote_addr;
     proxy_set_header x-webobjects-server-name $server_name;
-    proxy_set_header x-webobjects-server-url $scheme://$host:$server_port;
-    proxy_set_header x-webobjects-server-port $server_port;
+    proxy_set_header x-webobjects-server-url $real_scheme://$host:$real_port;
+    proxy_set_header x-webobjects-server-port $real_port;
     client_body_buffer_size 128k;
     client_max_body_size 100m;
     break;

docs/first_steps.md

@@ -103,6 +103,8 @@ Recreate affected containers by running `docker-compose up -d`.
     ProxyPass / http://127.0.0.1:8080/
     ProxyPassReverse / http://127.0.0.1:8080/
     ProxyPreserveHost Off
+    RequestHeader set X-Forwarded-Proto "https"
+    RequestHeader set X-Forwarded-Port "443"
     your-ssl-configuration-here
     [...]
 
@@ -127,15 +129,28 @@ server {
     your-ssl-configuration-here
     location / {
         proxy_pass http://127.0.0.1:8080/;
-        proxy_redirect http://127.0.0.1:8080/ $scheme://$host:$server_port/;
         proxy_set_header X-Real-IP $remote_addr;
         proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
         proxy_set_header X-Forwarded-Proto $scheme;
+        proxy_set_header X-Forwarded-Port $server_port;
     }
     [...]
 }
 ```
 
+### HAProxy
+```
+frontend https-in
+  bind :::443 v4v6 ssl crt mailcow.pem
+  default_backend mailcow
+
+backend mailcow
+  option forwardfor
+  http-request set-header X-Forwarded-Proto https
+  http-request set-header X-Forwarded-Port %[dst_port]
+  server mailcow 127.0.0.1:8080 check
+```
+
 ## Optional: Setup a relayhost
 
 Insert these lines to `data/conf/postfix/main.cf`. "relayhost" does already exist (empty), just change its value.