feat(api): wire DNS propagation for traffic-inspector custom hosts (fix1)

src/app/api/tools/traffic-inspector/hosts/[host]/route.ts

@@ -1,5 +1,5 @@
 /**
- * DELETE /api/tools/traffic-inspector/hosts/[host] — remove a custom host
+ * DELETE /api/tools/traffic-inspector/hosts/[host] — remove a custom host + DNS cleanup
  * PATCH  /api/tools/traffic-inspector/hosts/[host] — toggle enabled flag
  *
  * LOCAL_ONLY enforced by routeGuard.
@@ -8,6 +8,8 @@
 import { buildErrorBody, sanitizeErrorMessage } from "@omniroute/open-sse/utils/error.ts";
 import { z } from "zod";
 import { removeCustomHost, toggleCustomHost, listCustomHosts } from "@/lib/db/inspectorCustomHosts";
+import { getCachedPassword } from "@/mitm/manager";
+import { removeDNSEntries } from "@/mitm/dns/dnsConfig";
 
 interface Params {
   params: Promise<{ host: string }>;
@@ -23,7 +25,6 @@ export async function DELETE(_request: Request, { params }: Params): Promise<Res
 
   try {
     removeCustomHost(decodedHost);
-    return new Response(null, { status: 204 });
   } catch (err) {
     const msg = sanitizeErrorMessage(err);
     return new Response(JSON.stringify(buildErrorBody(500, msg || "Failed to remove host")), {
@@ -31,6 +32,33 @@ export async function DELETE(_request: Request, { params }: Params): Promise<Res
       headers: { "content-type": "application/json" },
     });
   }
+
+  // DNS cleanup — only possible when the MITM proxy is running (password cached).
+  const sudoPassword = getCachedPassword();
+  if (sudoPassword) {
+    try {
+      await removeDNSEntries([decodedHost], sudoPassword);
+    } catch {
+      // DNS cleanup failure is non-fatal: DB record was removed.
+      // Return 204 with a header warning rather than failing.
+      return new Response(null, {
+        status: 204,
+        headers: {
+          "x-dns-warning": `DNS entry for ${decodedHost} could not be removed — restart the proxy or remove manually`,
+        },
+      });
+    }
+  } else {
+    return new Response(null, {
+      status: 204,
+      headers: {
+        "x-dns-warning":
+          "DNS routing requires the MITM proxy to be running with a cached sudo password",
+      },
+    });
+  }
+
+  return new Response(null, { status: 204 });
 }
 
 export async function PATCH(request: Request, { params }: Params): Promise<Response> {

src/app/api/tools/traffic-inspector/hosts/route.ts

@@ -1,10 +1,10 @@
 /**
  * GET  /api/tools/traffic-inspector/hosts — list custom host capture entries
- * POST /api/tools/traffic-inspector/hosts — add a host (DB record)
+ * POST /api/tools/traffic-inspector/hosts — add a host (DB record + DNS propagation)
  *
  * The DB record enables the MITM proxy to SNI-certify the host on demand.
- * DNS /etc/hosts edits are out of scope for this route — clients that need
- * OS-level redirect must use the Custom Hosts setup guide (requires sudo).
+ * When a cached sudo password is available (MITM proxy running), DNS /etc/hosts
+ * entries are also added so OS traffic is redirected to the local proxy.
  *
  * LOCAL_ONLY enforced by routeGuard.
  */
@@ -12,6 +12,8 @@
 import { buildErrorBody, sanitizeErrorMessage } from "@omniroute/open-sse/utils/error.ts";
 import { InspectorCustomHostSchema } from "@/shared/schemas/inspector";
 import { listCustomHosts, addCustomHost } from "@/lib/db/inspectorCustomHosts";
+import { getCachedPassword } from "@/mitm/manager";
+import { addDNSEntries } from "@/mitm/dns/dnsConfig";
 
 export async function GET(): Promise<Response> {
   try {
@@ -57,5 +59,28 @@ export async function POST(request: Request): Promise<Response> {
     });
   }
 
-  return Response.json({ ok: true, host }, { status: 201 });
+  // DNS propagation — only possible when the MITM proxy is running (password cached).
+  const sudoPassword = getCachedPassword();
+  if (sudoPassword) {
+    try {
+      await addDNSEntries([host], sudoPassword);
+    } catch (err) {
+      // DNS failure is non-fatal: DB record was saved; warn but do not fail the request.
+      const msg = sanitizeErrorMessage(err);
+      return Response.json(
+        { ok: true, host, warning: `DNS routing entry could not be added: ${msg}` },
+        { status: 201 }
+      );
+    }
+    return Response.json({ ok: true, host }, { status: 201 });
+  }
+
+  return Response.json(
+    {
+      ok: true,
+      host,
+      warning: "DNS routing requires the MITM proxy to be running with a cached sudo password",
+    },
+    { status: 201 }
+  );
 }