feat: added support for ncm (#15)

package.json

@@ -20,7 +20,7 @@
     "@chakra-ui/react": "^2.6.1",
     "@emotion/react": "^11.11.0",
     "@emotion/styled": "^11.11.0",
-    "@jixun/libparakeet": "0.0.0-exp.18",
+    "@jixun/libparakeet": "0.0.0-exp.19",
     "@reduxjs/toolkit": "^1.9.5",
     "framer-motion": "^10.12.12",
     "nanoid": "^4.0.2",

pnpm-lock.yaml

@@ -14,8 +14,8 @@ dependencies:
     specifier: ^11.11.0
     version: 11.11.0(@emotion/react@11.11.0)(@types/react@18.2.6)(react@18.2.0)
   '@jixun/libparakeet':
-    specifier: 0.0.0-exp.18
-    version: 0.0.0-exp.18
+    specifier: 0.0.0-exp.19
+    version: 0.0.0-exp.19
   '@reduxjs/toolkit':
     specifier: ^1.9.5
     version: 1.9.5(react-redux@8.0.5)(react@18.2.0)
@@ -3060,9 +3060,9 @@ packages:
       chalk: 4.1.2
     dev: true
 
-  /@jixun/libparakeet@0.0.0-exp.18:
+  /@jixun/libparakeet@0.0.0-exp.19:
     resolution:
-      { integrity: sha512-KLUCxr6x47hDs1tszY8uyR8fgiB+b2UIFSgCg9GEs+AiB+oFTyQlhZXbKmyfDOuWSDiBcdKJvmXq29x3zPDNEQ== }
+      { integrity: sha512-FePuE49fCIRppzTJzaeISJhtvf1mFyU4MpVlQigmlR2CLAXtEkJz0HhsoumJwzcWv6UQJMUSagtXoTa8pxZ4ww== }
     dev: false
 
   /@jridgewell/gen-mapping@0.3.3:

src/decrypt-worker/crypto/CryptoFactory.ts

@@ -1,4 +1,5 @@
 import { CryptoFactory } from './CryptoBase';
+import { NCMCrypto } from './ncm/ncm_pc';
 
 import { QMC1Crypto } from './qmc/qmc_v1';
 import { QMC2Crypto } from './qmc/qmc_v2';
@@ -12,6 +13,9 @@ export const allCryptoFactories: CryptoFactory[] = [
   // QMCv2 (*.mflac)
   QMC2Crypto.make,
 
+  // NCM (*.ncm)
+  NCMCrypto.make,
+
   // Crypto that does not implement "checkBySignature" or need to decrypt the entire file and then check audio type,
   //   should be moved to the bottom of the list for performance reasons.
 

src/decrypt-worker/crypto/ncm/ncm_pc.key.ts

@@ -0,0 +1,2 @@
+export const NCM_KEY = 'hzHRAmso5kInbaxW';
+export const NCM_MAGIC_HEADER = new Uint8Array([0x43, 0x54, 0x45, 0x4e, 0x46, 0x44, 0x41, 0x4d]);

src/decrypt-worker/crypto/ncm/ncm_pc.ts

@@ -0,0 +1,21 @@
+import { transformBlob } from '~/decrypt-worker/util/transformBlob';
+import type { CryptoBase } from '../CryptoBase';
+import { NCM_KEY, NCM_MAGIC_HEADER } from './ncm_pc.key';
+
+export class NCMCrypto implements CryptoBase {
+  cryptoName = 'NCM/PC';
+  checkByDecryptHeader = false;
+
+  async checkBySignature(buffer: ArrayBuffer) {
+    const view = new DataView(buffer, 0, NCM_MAGIC_HEADER.byteLength);
+    return NCM_MAGIC_HEADER.every((value, i) => value === view.getUint8(i));
+  }
+
+  async decrypt(buffer: ArrayBuffer): Promise<Blob> {
+    return transformBlob(buffer, (p) => p.make.NeteaseNCM(NCM_KEY));
+  }
+
+  public static make() {
+    return new NCMCrypto();
+  }
+}