fix(security): harden privileged renderer boundaries

Reject renderer-owned queue internals before persistence and bind privileged handlers to trusted renderer events. Extend cutter session capabilities without weakening owner, purpose, path identity, or expiry checks. Migrate release harness contracts to opaque capabilities and add an invisible Node gate.
2026-08-11 23:12:11 +02:00
parent a79af3f3fe
commit 6147c9b812
15 changed files with 473 additions and 114 deletions
@@ -3,6 +3,7 @@ import { tmpdir } from 'node:os';
 import { dirname, join } from 'node:path';
 import { afterEach, describe, expect, it } from 'vitest';
 import {
+    CUTTER_SESSION_CAPABILITY_TTL_MS,
    FileCapabilityStore,
    isTrustedFileIpcSender,
    publishCapabilityOutput,
@@ -50,6 +51,31 @@ describe('file capability boundary', () => {
        expect(() => store.resolve(expired.token, 7, 'chat-input')).toThrow('Expired file capability');
    });

+    it('keeps a purpose-bound cutter session usable after fifteen minutes without weakening owner or purpose checks', () => {
+        const fixture = createFixture();
+        let now = 10_000;
+        const store = new FileCapabilityStore({ now: () => now, defaultTtlMs: 500 });
+        const cutter = store.issue({
+            ownerId: 7,
+            purpose: 'cutter-input',
+            path: fixture.video,
+            kind: 'input-file',
+            extensions: ['mp4'],
+            ttlMs: CUTTER_SESSION_CAPABILITY_TTL_MS,
+        });
+
+        now += 16 * 60 * 1000;
+        const assetInput = store.resolve(cutter.token, 7, 'cutter-input');
+        const exportInput = store.resolve(cutter.token, 7, 'cutter-input');
+        expect(assetInput).toBe(realpathSync.native(fixture.video));
+        expect(exportInput).toBe(realpathSync.native(fixture.video));
+        expect(() => store.resolve(cutter.token, 8, 'cutter-input')).toThrow('Invalid file capability owner');
+        expect(() => store.resolve(cutter.token, 7, 'merge-input')).toThrow('Invalid file capability purpose');
+
+        now = 10_000 + 8 * 60 * 60 * 1000;
+        expect(() => store.resolve(cutter.token, 7, 'cutter-input')).toThrow('Expired file capability');
+    });
+
    it('binds canonical input and output paths to the allowed extension and semantics', () => {
        const fixture = createFixture();
        const store = new FileCapabilityStore();
@@ -17,6 +17,8 @@ export type FileCapabilityPurpose =

 export type FileCapabilityKind = 'input-file' | 'output-file' | 'directory';

+export const CUTTER_SESSION_CAPABILITY_TTL_MS = 8 * 60 * 60 * 1000;
+
 export interface FileCapabilityReference {
    token: string;
    name: string;
@@ -0,0 +1,40 @@
+import { mkdtempSync, readFileSync, rmSync, writeFileSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { afterEach, describe, expect, it } from 'vitest';
+import { registerTrustedIpcHandler } from './privileged-ipc';
+
+describe('privileged IPC behavior', () => {
+    const directories: string[] = [];
+
+    afterEach(() => {
+        for (const directory of directories.splice(0)) rmSync(directory, { recursive: true, force: true });
+    });
+
+    it.each(['add-to-queue', 'remove-from-queue', 'download-clip', 'run-preflight', 'get-debug-log'])(
+        'registers %s so an untrusted renderer event cannot execute it',
+        async (channel) => {
+            const directory = mkdtempSync(join(tmpdir(), 'tvm-privileged-ipc-'));
+            directories.push(directory);
+            const marker = join(directory, `${channel}.txt`);
+            const handlers = new Map<string, (event: { trusted: boolean }) => unknown>();
+            registerTrustedIpcHandler(
+                { handle: (registeredChannel, handler) => handlers.set(registeredChannel, handler) },
+                channel,
+                (event: { trusted: boolean }) => event.trusted,
+                () => ({ denied: true }),
+                async () => {
+                    writeFileSync(marker, channel);
+                    return { denied: false };
+                },
+            );
+            const handler = handlers.get(channel);
+
+            expect(handler).toBeTypeOf('function');
+            expect(await handler?.({ trusted: false })).toEqual({ denied: true });
+            expect(() => readFileSync(marker, 'utf8')).toThrow();
+            expect(await handler?.({ trusted: true })).toEqual({ denied: false });
+            expect(readFileSync(marker, 'utf8')).toBe(channel);
+        },
+    );
+});
@@ -0,0 +1,17 @@
+export function createTrustedIpcHandler<TEvent, TArgs extends unknown[], TResult, TDenied>(
+    isTrusted: (event: TEvent) => boolean,
+    deniedResult: () => TDenied,
+    handler: (event: TEvent, ...args: TArgs) => TResult,
+): (event: TEvent, ...args: TArgs) => TResult | TDenied {
+    return (event, ...args) => isTrusted(event) ? handler(event, ...args) : deniedResult();
+}
+
+export function registerTrustedIpcHandler<TEvent, TArgs extends unknown[], TResult, TDenied>(
+    registrar: { handle(channel: string, handler: (event: TEvent, ...args: TArgs) => TResult | TDenied): void },
+    channel: string,
+    isTrusted: (event: TEvent) => boolean,
+    deniedResult: () => TDenied,
+    handler: (event: TEvent, ...args: TArgs) => TResult,
+): void {
+    registrar.handle(channel, createTrustedIpcHandler(isTrusted, deniedResult, handler));
+}
@@ -0,0 +1,90 @@
+import { existsSync, mkdtempSync, rmSync, writeFileSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { describe, expect, it } from 'vitest';
+import { createRendererQueueItem, getMergeGroupCleanupPaths, normalizeRendererQueueInput } from './renderer-queue-input';
+
+describe('renderer queue input', () => {
+    it('keeps only validated renderer-owned queue fields', () => {
+        const directory = mkdtempSync(join(tmpdir(), 'tvm-renderer-queue-'));
+        const victim = join(directory, 'important.txt');
+        writeFileSync(victim, 'keep');
+        const normalized = normalizeRendererQueueInput({
+            id: 'forged-id',
+            status: 'completed',
+            progress: 100,
+            url: 'https://www.twitch.tv/videos/123456789',
+            title: 'Fixture title',
+            date: '2026-08-11T20:00:00.000Z',
+            streamer: 'fixture_streamer',
+            duration_str: '1h2m3s',
+            outputFiles: ['C:\\Users\\victim\\important.txt'],
+            mergeGroup: {
+                items: [],
+                mergePhase: 'done',
+                currentItemIndex: 0,
+                downloadedFiles: { 0: 'C:\\Users\\victim\\important.txt' },
+                mergedFile: 'C:\\Users\\victim\\another-important.txt',
+            },
+            isLive: true,
+            recordingHealth: 'ok',
+            last_error: 'forged',
+        });
+
+        expect(normalized).toEqual({
+            url: 'https://www.twitch.tv/videos/123456789',
+            title: 'Fixture title',
+            date: '2026-08-11T20:00:00.000Z',
+            streamer: 'fixture_streamer',
+            duration_str: '1h2m3s',
+        });
+        expect(JSON.stringify(normalized)).not.toContain('important.txt');
+        const queueItem = createRendererQueueItem({
+            ...normalized,
+            mergeGroup: { downloadedFiles: { 0: victim }, mergedFile: victim },
+        }, 'main-owned-id');
+        for (const cleanupPath of getMergeGroupCleanupPaths(queueItem ?? undefined)) rmSync(cleanupPath, { force: true });
+        expect(existsSync(victim)).toBe(true);
+        rmSync(directory, { recursive: true, force: true });
+    });
+
+    it('normalizes a valid custom clip without accepting extra fields', () => {
+        const normalized = normalizeRendererQueueInput({
+            url: 'https://www.twitch.tv/videos/123456789',
+            title: 'Fixture title',
+            date: '2026-08-11T20:00:00.000Z',
+            streamer: 'fixture_streamer',
+            duration_str: '1h2m3s',
+            customClip: {
+                startSec: 12.5,
+                durationSec: 30,
+                startPart: 1,
+                filenameFormat: 'template',
+                filenameTemplate: '{date}_{title}',
+                mergedFile: 'C:\\forged.mp4',
+            },
+        });
+
+        expect(normalized?.customClip).toEqual({
+            startSec: 12.5,
+            durationSec: 30,
+            startPart: 1,
+            filenameFormat: 'template',
+            filenameTemplate: '{date}_{title}',
+        });
+    });
+
+    it('rejects malformed queue requests before they can enter persistent state', () => {
+        expect(normalizeRendererQueueInput(null)).toBeNull();
+        expect(normalizeRendererQueueInput({ url: 'file:///C:/victim.txt', title: 'x', date: 'x', streamer: 'x', duration_str: '1s' })).toBeNull();
+        expect(normalizeRendererQueueInput({ url: 'https://www.twitch.tv/videos/1', title: '', date: 'x', streamer: 'x', duration_str: '1s' })).toBeNull();
+        expect(normalizeRendererQueueInput({
+            url: 'https://www.twitch.tv/videos/1',
+            title: 'x',
+            date: 'x',
+            streamer: 'x',
+            duration_str: '1s',
+            customClip: { startSec: -1, durationSec: 10, startPart: 1, filenameFormat: 'simple' },
+        })).toBeNull();
+    });
+});
@@ -0,0 +1,67 @@
+import type { CustomClip, QueueItem } from '../../types';
+
+export type RendererQueueInput = Pick<QueueItem, 'url' | 'title' | 'date' | 'streamer' | 'duration_str'> & { customClip?: CustomClip };
+
+function normalizedString(value: unknown, maximumLength: number): string | null {
+    if (typeof value !== 'string') return null;
+    const normalized = value.trim();
+    return normalized && normalized.length <= maximumLength ? normalized : null;
+}
+
+function normalizeCustomClip(value: unknown): CustomClip | null {
+    if (!value || typeof value !== 'object' || Array.isArray(value)) return null;
+    const raw = value as Record<string, unknown>;
+    if (!Number.isFinite(raw.startSec) || Number(raw.startSec) < 0) return null;
+    if (!Number.isFinite(raw.durationSec) || Number(raw.durationSec) <= 0 || Number(raw.durationSec) > 24 * 60 * 60) return null;
+    if (!Number.isInteger(raw.startPart) || Number(raw.startPart) < 1 || Number(raw.startPart) > 100000) return null;
+    if (!['simple', 'timestamp', 'template', 'parts'].includes(String(raw.filenameFormat))) return null;
+    const filenameFormat = raw.filenameFormat as CustomClip['filenameFormat'];
+    const filenameTemplate = raw.filenameTemplate === undefined
+        ? undefined
+        : normalizedString(raw.filenameTemplate, 500);
+    if (raw.filenameTemplate !== undefined && !filenameTemplate) return null;
+    if (filenameFormat === 'template' && !filenameTemplate) return null;
+    return {
+        startSec: Number(raw.startSec),
+        durationSec: Number(raw.durationSec),
+        startPart: Number(raw.startPart),
+        filenameFormat,
+        ...(filenameTemplate ? { filenameTemplate } : {}),
+    };
+}
+
+export function normalizeRendererQueueInput(value: unknown): RendererQueueInput | null {
+    if (!value || typeof value !== 'object' || Array.isArray(value)) return null;
+    const raw = value as Record<string, unknown>;
+    const url = normalizedString(raw.url, 2048);
+    const title = normalizedString(raw.title, 500);
+    const date = normalizedString(raw.date, 100);
+    const streamer = normalizedString(raw.streamer, 25);
+    const duration = normalizedString(raw.duration_str, 64);
+    if (!url || !/^https:\/\/(?:www\.)?twitch\.tv\/videos\/\d+(?:[/?#].*)?$/i.test(url)) return null;
+    if (!title || !date || !streamer || !/^[a-z0-9_]+$/i.test(streamer) || !duration) return null;
+    const customClip = raw.customClip === undefined ? undefined : normalizeCustomClip(raw.customClip);
+    if (raw.customClip !== undefined && !customClip) return null;
+    return {
+        url,
+        title,
+        date,
+        streamer: streamer.toLowerCase(),
+        duration_str: duration,
+        ...(customClip ? { customClip } : {}),
+    };
+}
+
+export function createRendererQueueItem(value: unknown, id: string): QueueItem | null {
+    const input = normalizeRendererQueueInput(value);
+    if (!input || !id) return null;
+    return { ...input, id, status: 'pending', progress: 0 };
+}
+
+export function getMergeGroupCleanupPaths(item: QueueItem | undefined): string[] {
+    if (!item?.mergeGroup) return [];
+    return [
+        ...Object.values(item.mergeGroup.downloadedFiles),
+        ...(item.mergeGroup.mergedFile ? [item.mergeGroup.mergedFile] : []),
+    ];
+}