fix(portal): identity header deleted-after-set → portal showed no data

src/services/caddyConfig.js

@@ -730,7 +730,7 @@ function buildCaddyConfig(injectedRoutes, options = {}) {
           match: [{ path: ['/.well-known/acme-challenge/*'] }],
           handle: [],
         },
-        // (1) Internal sources → portal (remote_ip = real TCP source; header strip/set unchanged).
+        // (1) Internal sources → portal (remote_ip = real TCP source; reverse_proxy SETS the identity header).
         {
           match: [{ remote_ip: { ranges: INTERNAL_ONLY_RANGES } }],
           handle: [
@@ -748,9 +748,12 @@ function buildCaddyConfig(injectedRoutes, options = {}) {
               upstreams: [{ dial: `127.0.0.1:${config.app.port}` }],
               headers: {
                 request: {
-                  // Delete first: prevent any client-supplied copy from reaching Node.
-                  delete: ['X-GC-Portal-Peer-IP'],
-                  // Set from real TCP source — Caddy resolves this before XFF processing.
+                  // SET ONLY — do NOT also `delete` this header here. Caddy's header
+                  // handler applies `delete` AFTER `set`, so a `delete` + `set` on the
+                  // SAME header nukes the value we just set, and Node never receives the
+                  // identity header (portal then shows no per-device data). `set` alone is
+                  // already forgery-safe: it REPLACES any client-supplied copy with the
+                  // real TCP source, so a VPN client cannot inject a foreign peer IP.
                   set: { 'X-GC-Portal-Peer-IP': ['{http.request.remote.host}'] },
                 },
               },

tests/portal_dns_caddy.test.js

@@ -50,18 +50,35 @@ test('renderHostsContent includes a home.<domain> A-record at the gateway IP', (
     'home A-record FQDN missing');
 });
 
-// ─── 2. Caddy site with reserved-header handling ─────────────────────────
-test('buildCaddyConfig adds an internal home.<domain> site with strip+set of reserved header', () => {
+// ─── 2. Caddy site SETS the reserved identity header (set-only, never delete+set) ──
+test('portal gate route SETS X-GC-Portal-Peer-IP from the real TCP source and does NOT also delete it', () => {
   const cfg = caddyConfigMod.buildCaddyConfig();
   const wantHost = `home.${config.dns.domain}`;
-  const json = JSON.stringify(cfg);
-
-  assert.ok(json.includes(wantHost),
-    `home.<domain> site missing from Caddy config (looked for ${wantHost})`);
-  assert.ok(json.includes('X-GC-Portal-Peer-IP'),
-    'reserved header X-GC-Portal-Peer-IP handling missing from Caddy config');
-  assert.ok(json.includes('{http.request.remote.host}'),
-    'real-IP placeholder {http.request.remote.host} missing from Caddy config');
+  const serverRoutes = cfg?.apps?.http?.servers?.srv0?.routes || [];
+
+  // Drill: outer host route → subroute → the remote_ip gate route → its reverse_proxy.
+  const homeRoute = serverRoutes.find(r =>
+    Array.isArray(r.match) && r.match.some(m => Array.isArray(m.host) && m.host.includes(wantHost)));
+  assert.ok(homeRoute, `home.<domain> route not found (looked for ${wantHost})`);
+  const innerRoutes = ((homeRoute.handle || []).find(h => h.handler === 'subroute') || {}).routes || [];
+  const gateRoute = innerRoutes.find(r =>
+    Array.isArray(r.match) && r.match.some(m => m.remote_ip));
+  assert.ok(gateRoute, 'remote_ip gate route missing inside the portal subroute');
+  const rp = (gateRoute.handle || []).find(h => h.handler === 'reverse_proxy');
+  assert.ok(rp, 'portal gate route has no reverse_proxy handler');
+
+  const reqHdr = (rp.headers && rp.headers.request) || {};
+  const setVals = (reqHdr.set && reqHdr.set['X-GC-Portal-Peer-IP']) || [];
+  assert.ok(setVals.includes('{http.request.remote.host}'),
+    'gate route must SET X-GC-Portal-Peer-IP from {http.request.remote.host} (the real TCP source)');
+
+  // REGRESSION GUARD: Caddy applies `delete` AFTER `set`, so a delete + set on the SAME
+  // header wipes the value we just set and Node never sees the identity header (portal
+  // shows no per-device data). `set` alone is already forgery-safe (it replaces any
+  // client-supplied copy). The gate route must therefore NOT delete this header.
+  const delVals = reqHdr.delete || [];
+  assert.ok(!delVals.includes('X-GC-Portal-Peer-IP'),
+    'gate route must NOT delete X-GC-Portal-Peer-IP — delete-after-set nukes the value Node needs');
 });
 
 // ─── 3. Internal-only (remote_ip gate in inner subroute + 404 fallback) ──────────