Aug 21 - Fixed Forwarded host

2026-08-21 13:14:37 -04:00
parent d04190ba09
commit 3bfd81c84c
4 changed files with 257 additions and 1 deletions
@@ -0,0 +1,72 @@
+# /etc/nginx/sites-available/jqc_multi
+# ─────────────────────────────────────────────────────────────────────────────
+# Tenant subdomains: *.jqc.app → 127.0.0.1:8000
+#
+# MT-24. The critical line in this file is:
+#
+#     proxy_set_header X-Forwarded-Host $host;
+#
+# Nginx forwards unrecognised client request headers upstream. Without this
+# line a client could send its own X-Forwarded-Host, and (when the app trusted
+# it) choose which tenant database the request bound to — pre-authentication,
+# from the open internet. Pinning it to $host makes the header say what nginx
+# observed, never what the client claimed. The app no longer trusts the header
+# at all (ProxyFix x_host=0), so this is the second of two independent layers.
+#
+# Keep both. Either alone closes the hole; both together mean a future change
+# to one does not silently reopen it.
+# ─────────────────────────────────────────────────────────────────────────────
+
+# ── Shared proxy header set ──────────────────────────────────────────────────
+# Included by every location that proxies, so a new location cannot forget one.
+# (Requires: include snippets in /etc/nginx/snippets/ or inline as below.)
+
+server {
+    listen 443 ssl;
+    http2 on;
+    server_name *.jqc.app;
+
+    client_max_body_size 50M;
+
+    # Static assets. NOTE: this serves the app's static tree directly, which
+    # includes app/static/uploads on a local-storage deploy — every photo is
+    # then readable by anyone who knows or guesses its URL, with no session
+    # check. Filenames are random UUIDs so they are not enumerable, but they
+    # are also not access-controlled and never expire.
+    # This is retired per tenant at R2 cutover, when media moves to short-lived
+    # presigned URLs. Until then, treat it as a known exposure.
+    location /static/ {
+        alias /home/jqc/janitorial_qc/app/static/;
+        expires 30d;
+    }
+
+    location / {
+        proxy_pass         http://127.0.0.1:8000;
+
+        proxy_set_header   Host              $host;
+        # MT-24 — pin, never inherit from the client. See header comment.
+        proxy_set_header   X-Forwarded-Host  $host;
+        proxy_set_header   X-Forwarded-Port  $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 $scheme;
+
+        proxy_read_timeout 60s;
+    }
+
+    ssl_certificate     /etc/letsencrypt/live/jqc.app-0001/fullchain.pem;
+    ssl_certificate_key /etc/letsencrypt/live/jqc.app-0001/privkey.pem;
+    include             /etc/letsencrypt/options-ssl-nginx.conf;
+    ssl_dhparam         /etc/letsencrypt/ssl-dhparams.pem;
+}
+
+server {
+    listen 80;
+    server_name *.jqc.app;
+
+    # MT-24: the Certbot-generated `if ($host = *.jqc.app)` test is a literal
+    # string comparison — it never matches a wildcard server_name, so plain
+    # HTTP requests to tenant subdomains fell through with no redirect. This
+    # block matches only *.jqc.app already, so redirect unconditionally.
+    return 301 https://$host$request_uri;
+}