chore: initial commit - CloudSearch v0.0.2

2026-05-15 05:50:50 +08:00
commit d83225d736
102 changed files with 37926 additions and 0 deletions
--- a/packages/backend/src/utils/crypto.ts
+++ b/packages/backend/src/utils/crypto.ts
@@ -0,0 +1,111 @@
+/**
+ * AES-256-GCM 加解密工具
+ * 
+ * 用于保护数据库中存储的网盘 Cookie。
+ * 加密密钥从环境变量 COOKIE_ENCRYPTION_KEY 读取，
+ * 未设置时自动生成随机密钥（仅当前进程有效，重启后旧数据不可解密）。
+ * 
+ * 生产环境必须设置 COOKIE_ENCRYPTION_KEY！
+ */
+import * as crypto from 'crypto';
+
+const ALGORITHM = 'aes-256-gcm';
+const IV_LENGTH = 12;  // 96-bit nonce for GCM
+const TAG_LENGTH = 16; // 128-bit auth tag
+const KEY_LENGTH = 32; // 256-bit key
+
+let ENCRYPTION_KEY: Buffer | null = null;
+
+function getKey(): Buffer {
+  if (ENCRYPTION_KEY) return ENCRYPTION_KEY;
+
+  const envKey = process.env.COOKIE_ENCRYPTION_KEY;
+  if (envKey && envKey.length >= 32) {
+    // Use SHA-256 to derive a consistent 32-byte key from any length input
+    ENCRYPTION_KEY = crypto.createHash('sha256').update(envKey).digest();
+    console.log('[Crypto] Cookie encryption enabled (key from COOKIE_ENCRYPTION_KEY)');
+  } else if (envKey) {
+    // Short key: still use SHA-256
+    ENCRYPTION_KEY = crypto.createHash('sha256').update(envKey).digest();
+    console.log('[Crypto] Cookie encryption enabled (key from COOKIE_ENCRYPTION_KEY, SHA-256 derived)');
+  } else {
+    // Default stable key (not ephemeral) — data survives container restart
+    ENCRYPTION_KEY = crypto.createHash('sha256').update('cloudsearch-cookie-key-v1').digest();
+    console.log('[Crypto] Cookie encryption enabled (built-in default key — set COOKIE_ENCRYPTION_KEY in .env for extra security)');
+  }
+  return ENCRYPTION_KEY;
+}
+
+/**
+ * Encrypt plaintext. Returns base64-encoded ciphertext (includes IV + auth tag).
+ */
+export function encrypt(plaintext: string): string {
+  if (!plaintext) return '';
+  const key = getKey();
+  const iv = crypto.randomBytes(IV_LENGTH);
+  const cipher = crypto.createCipheriv(ALGORITHM, key, iv);
+
+  const encrypted = Buffer.concat([
+    cipher.update(plaintext, 'utf8'),
+    cipher.final(),
+  ]);
+  const tag = cipher.getAuthTag();
+
+  // Format: iv (12) + tag (16) + ciphertext
+  const combined = Buffer.concat([iv, tag, encrypted]);
+  return combined.toString('base64');
+}
+
+/**
+ * Decrypt base64-encoded ciphertext. Returns original plaintext.
+ * Returns empty string if decryption fails (corrupted data or wrong key).
+ */
+export function decrypt(encoded: string): string {
+  if (!encoded) return '';
+  try {
+    const key = getKey();
+    const combined = Buffer.from(encoded, 'base64');
+
+    if (combined.length < IV_LENGTH + TAG_LENGTH + 1) {
+      console.warn('[Crypto] Ciphertext too short, returning as-is (possibly unencrypted legacy data)');
+      // Legacy data: stored as plaintext before encryption was added
+      return encoded;
+    }
+
+    const iv = combined.subarray(0, IV_LENGTH);
+    const tag = combined.subarray(IV_LENGTH, IV_LENGTH + TAG_LENGTH);
+    const ciphertext = combined.subarray(IV_LENGTH + TAG_LENGTH);
+
+    const decipher = crypto.createDecipheriv(ALGORITHM, key, iv);
+    decipher.setAuthTag(tag);
+
+    const decrypted = Buffer.concat([
+      decipher.update(ciphertext),
+      decipher.final(),
+    ]);
+    return decrypted.toString('utf8');
+  } catch (err: any) {
+    // If it looks like base64 but decryption fails, it might be legacy plaintext
+    // stored before encryption was enabled. Try returning as-is.
+    if (err.message?.includes('unsupported state') || err.message?.includes('authentication')) {
+      console.warn('[Crypto] Decryption failed (possibly legacy plaintext), returning as-is');
+      return encoded;
+    }
+    console.error('[Crypto] Decryption error:', err.message);
+    return '';
+  }
+}
+
+/**
+ * Check if a string appears to be encrypted (base64 with IV+tag prefix).
+ * Used for migration: re-encrypt legacy plaintext cookies.
+ */
+export function isEncrypted(value: string): boolean {
+  if (!value) return false;
+  try {
+    const combined = Buffer.from(value, 'base64');
+    return combined.length > IV_LENGTH + TAG_LENGTH;
+  } catch {
+    return false;
+  }
+}