fix(auth): restore permission boundary safeguards

backend/src/auth/authorization.ts

@@ -22,3 +22,23 @@ export function requirePermission(
   if (hasPermission(principal, permission)) return principal;
   return reply.code(403).send({ code: "auth_forbidden", error: "This operation is not permitted" });
 }
+
+/** Permit non-browser clients and browsers whose declared origin matches the request host. */
+export function requireSameOriginOrNonBrowser(
+  request: FastifyRequest,
+  reply: FastifyReply,
+): FastifyReply | undefined {
+  const origin = request.headers.origin;
+  if (origin === undefined) return undefined;
+  if (typeof origin !== "string" || typeof request.headers.host !== "string") {
+    return reply.code(403).send({ code: "auth_forbidden", error: "This operation is not permitted" });
+  }
+  try {
+    const supplied = new URL(origin);
+    const expected = new URL(`${request.protocol}://${request.headers.host}`);
+    if (supplied.origin === expected.origin) return undefined;
+  } catch {
+    // Invalid browser origins are forbidden below.
+  }
+  return reply.code(403).send({ code: "auth_forbidden", error: "This operation is not permitted" });
+}

backend/src/routes/pi-management.ts

@@ -1,5 +1,9 @@
 import type { FastifyInstance, FastifyReply, FastifyRequest } from "fastify";
-import { isPrincipalContext, requirePermission } from "../auth/authorization.js";
+import {
+  isPrincipalContext,
+  requirePermission,
+  requireSameOriginOrNonBrowser,
+} from "../auth/authorization.js";
 import { PiManagementError, type PiManagementService } from "../pi/management.js";
 
 export function piManagementRoutes(
@@ -26,6 +30,10 @@ async function run<T>(
 ): Promise<T | FastifyReply> {
   const principal = requirePermission(request, reply, "pi.manage");
   if (!isPrincipalContext(principal)) return principal;
+  if (principal.issuer === "local" && isWrite(request.method)) {
+    const csrfDenied = requireSameOriginOrNonBrowser(request, reply);
+    if (csrfDenied) return csrfDenied;
+  }
   try {
     return await action();
   } catch (error) {
@@ -36,3 +44,7 @@ async function run<T>(
     return reply.code(503).send({ code: "pi_management_unavailable", error: "Pi management is unavailable" });
   }
 }
+
+function isWrite(method: string): boolean {
+  return method === "POST" || method === "PUT" || method === "PATCH" || method === "DELETE";
+}

backend/src/routes/sessions.ts

@@ -102,7 +102,8 @@ export function sessionRoutes(
     admissionLeases.set(req, release);
   });
   app.addHook("preHandler", async (req, reply) => {
-    if (req.url === "/runtime/prewarm" || req.url === "/sessions" || req.url.startsWith("/sessions/")) {
+    const pathname = req.url.split("?", 1)[0];
+    if (pathname === "/runtime/prewarm" || pathname === "/sessions" || pathname.startsWith("/sessions/")) {
       const principal = requirePermission(req, reply, "session.use");
       if (!isPrincipalContext(principal)) return principal;
     }

backend/src/routes/sql.ts

@@ -3,7 +3,7 @@ import type { ThtRunner } from "../tht/tht-runner.js";
 import type { PrincipalContext } from "../auth/principal.js";
 import type { Settings } from "../settings/settings-store.js";
 import type { WorkspaceRegistry } from "../workspaces/registry.js";
-import { isPrincipalContext, requirePermission } from "../auth/authorization.js";
+import { hasPermission, isPrincipalContext, requirePermission } from "../auth/authorization.js";
 
 export function sqlRoutes(app: FastifyInstance, deps: {
   tht: ThtRunner; getSettings: (principal: PrincipalContext) => Promise<Settings>;
@@ -13,11 +13,16 @@ export function sqlRoutes(app: FastifyInstance, deps: {
     const runner = deps.tht as any;
     return typeof runner.withPrincipal === "function" ? runner.withPrincipal(principal) : runner;
   };
+  const readPrincipal = (principal: PrincipalContext): PrincipalContext => ({
+    ...principal,
+    // The harness still consumes this compatibility bit; it must never exceed session.read_all.
+    isAdmin: hasPermission(principal, "session.read_all"),
+  });
   const isNotFound = (error: unknown) => /not found|non trovata|inesistente|404/i.test(
     error instanceof Error ? error.message : String(error),
   );
   const locate = async (principal: PrincipalContext, id: string, legacyWorkspace?: string) => {
-    const runner = runnerFor(principal);
+    const runner = runnerFor(readPrincipal(principal));
     if (typeof runner.sessionShow !== "function") return { manifest: {}, workspace: legacyWorkspace };
     const registry = deps.workspaceRegistry as Partial<WorkspaceRegistry>;
     const revisions = typeof registry.listRetainedSnapshots === "function"
@@ -65,7 +70,7 @@ export function sqlRoutes(app: FastifyInstance, deps: {
       return reply.code(503).send({ error: "session storage is unavailable" });
     }
     try {
-      return await runnerFor(principal).sqlPreview(id, { limit, offset }, workspace);
+      return await runnerFor(readPrincipal(principal)).sqlPreview(id, { limit, offset }, workspace);
     } catch (error: any) {
       return reply.code(500).send({ error: error.message ?? String(error) });
     }
@@ -87,7 +92,7 @@ export function sqlRoutes(app: FastifyInstance, deps: {
       return reply.code(503).send({ error: "session storage is unavailable" });
     }
     try {
-      return await runnerFor(principal).sqlExport(id, workspace);
+      return await runnerFor(readPrincipal(principal)).sqlExport(id, workspace);
     } catch (error: any) {
       return reply.code(500).send({ error: error.message ?? String(error) });
     }