Initial public release v1.7.233

2026-08-01 22:29:53 +02:00
commit dc367633f5
152 changed files with 85159 additions and 0 deletions
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+import crypto from "node:crypto";
+
+const APP_KEY_MATERIAL = "MDD-v2-backup-aes256gcm-2026";
+const ALGORITHM = "aes-256-gcm";
+const IV_LENGTH = 12;
+const AUTH_TAG_LENGTH = 16;
+const MAGIC = Buffer.from("MDD1");
+
+function deriveKey(): Buffer {
+  return crypto.createHash("sha256").update(APP_KEY_MATERIAL).digest();
+}
+
+export function encryptBackup(plaintext: string): Buffer {
+  const key = deriveKey();
+  const iv = crypto.randomBytes(IV_LENGTH);
+  const cipher = crypto.createCipheriv(ALGORITHM, key, iv, { authTagLength: AUTH_TAG_LENGTH });
+  const encrypted = Buffer.concat([cipher.update(plaintext, "utf8"), cipher.final()]);
+  const authTag = cipher.getAuthTag();
+  return Buffer.concat([MAGIC, iv, authTag, encrypted]);
+}
+
+export function decryptBackup(data: Buffer): string {
+  if (data.length < MAGIC.length + IV_LENGTH + AUTH_TAG_LENGTH) {
+    throw new Error("Backup-Datei zu kurz oder ungültig");
+  }
+  const magic = data.subarray(0, MAGIC.length);
+  if (!magic.equals(MAGIC)) {
+    throw new Error("Keine gültige MDD-Backup-Datei (falsche Signatur)");
+  }
+  const iv = data.subarray(MAGIC.length, MAGIC.length + IV_LENGTH);
+  const authTag = data.subarray(MAGIC.length + IV_LENGTH, MAGIC.length + IV_LENGTH + AUTH_TAG_LENGTH);
+  const ciphertext = data.subarray(MAGIC.length + IV_LENGTH + AUTH_TAG_LENGTH);
+
+  const key = deriveKey();
+  const decipher = crypto.createDecipheriv(ALGORITHM, key, iv, { authTagLength: AUTH_TAG_LENGTH });
+  decipher.setAuthTag(authTag);
+  const decrypted = Buffer.concat([decipher.update(ciphertext), decipher.final()]);
+  return decrypted.toString("utf8");
+}