Merge pull request #221 from unlock-music/feature/qmc-meta

feature(QMCv2): 通过 SongID 在线查询歌曲信息

package-lock.json

@@ -11,7 +11,7 @@
       "license": "MIT",
       "dependencies": {
         "@babel/preset-typescript": "^7.16.5",
-        "@jixun/qmc2-crypto": "^0.0.5-R4",
+        "@jixun/qmc2-crypto": "^0.0.6-R1",
         "@unlock-music/joox-crypto": "^0.0.1-R5",
         "base64-js": "^1.5.1",
         "browser-id3-writer": "^4.4.0",
@@ -2986,9 +2986,9 @@
       }
     },
     "node_modules/@jixun/qmc2-crypto": {
-      "version": "0.0.5-R4",
-      "resolved": "https://registry.npmjs.org/@jixun/qmc2-crypto/-/qmc2-crypto-0.0.5-R4.tgz",
-      "integrity": "sha512-4xGClhxMd1BL7UjE+fZr+a4GYkfEjwU216WZ89ouANwR8Q27PhQrra+msEvM4J/mBBCjv/x/eIcS67XBasHKUQ=="
+      "version": "0.0.6-R1",
+      "resolved": "https://registry.npmjs.org/@jixun/qmc2-crypto/-/qmc2-crypto-0.0.6-R1.tgz",
+      "integrity": "sha512-G7oa28/tGozJIIkF2DS7RWewoDsKrmGM5JgthzCfB6P1psfCjpjwH21RhnY9RzNlfdGZBqyWkAKwXMiUx/xhNA=="
     },
     "node_modules/@mrmlnc/readdir-enhanced": {
       "version": "2.2.1",
@@ -23168,9 +23168,9 @@
       }
     },
     "@jixun/qmc2-crypto": {
-      "version": "0.0.5-R4",
-      "resolved": "https://registry.npmjs.org/@jixun/qmc2-crypto/-/qmc2-crypto-0.0.5-R4.tgz",
-      "integrity": "sha512-4xGClhxMd1BL7UjE+fZr+a4GYkfEjwU216WZ89ouANwR8Q27PhQrra+msEvM4J/mBBCjv/x/eIcS67XBasHKUQ=="
+      "version": "0.0.6-R1",
+      "resolved": "https://registry.npmjs.org/@jixun/qmc2-crypto/-/qmc2-crypto-0.0.6-R1.tgz",
+      "integrity": "sha512-G7oa28/tGozJIIkF2DS7RWewoDsKrmGM5JgthzCfB6P1psfCjpjwH21RhnY9RzNlfdGZBqyWkAKwXMiUx/xhNA=="
     },
     "@mrmlnc/readdir-enhanced": {
       "version": "2.2.1",

package.json

@@ -21,7 +21,7 @@
   },
   "dependencies": {
     "@babel/preset-typescript": "^7.16.5",
-    "@jixun/qmc2-crypto": "^0.0.5-R4",
+    "@jixun/qmc2-crypto": "^0.0.6-R1",
     "@unlock-music/joox-crypto": "^0.0.1-R5",
     "base64-js": "^1.5.1",
     "browser-id3-writer": "^4.4.0",

src/decrypt/qmc.ts

@@ -1,9 +1,9 @@
 import { QmcMapCipher, QmcRC4Cipher, QmcStaticCipher, QmcStreamCipher } from './qmc_cipher';
 import { AudioMimeType, GetArrayBuffer, SniffAudioExt } from '@/decrypt/utils';
-import { DecryptQMCWasm } from './qmc_wasm';
 
 import { DecryptResult } from '@/decrypt/entity';
 import { QmcDeriveKey } from '@/decrypt/qmc_key';
+import { DecryptQMCWasm } from '@/decrypt/qmc_wasm';
 import { extractQQMusicMeta } from '@/utils/qm_meta';
 
 interface Handler {
@@ -42,20 +42,27 @@ export async function Decrypt(file: Blob, raw_filename: string, raw_ext: string)
 
   const fileBuffer = await GetArrayBuffer(file);
   let musicDecoded: Uint8Array | undefined;
+  let musicID: number | string | undefined;
 
   if (version === 2 && globalThis.WebAssembly) {
     console.log('qmc: using wasm decoder');
+
     const v2Decrypted = await DecryptQMCWasm(fileBuffer);
-    // 如果 v2 检测失败，降级到 v1 再尝试一次
-    if (v2Decrypted) {
-      musicDecoded = v2Decrypted;
+    // 若 v2 检测失败，降级到 v1 再尝试一次
+    if (v2Decrypted.success) {
+      musicDecoded = v2Decrypted.data;
+      musicID = v2Decrypted.songId;
+    } else {
+      console.warn('qmc2-wasm failed with error %s', v2Decrypted.error || '(no error)');
     }
   }
+
   if (!musicDecoded) {
     // may throw error
     console.log('qmc: using js decoder');
     const d = new QmcDecoder(new Uint8Array(fileBuffer));
     musicDecoded = d.decrypt();
+    musicID = d.songID;
   }
 
   const ext = SniffAudioExt(musicDecoded, handler.ext);
@@ -65,6 +72,7 @@ export async function Decrypt(file: Blob, raw_filename: string, raw_ext: string)
     new Blob([musicDecoded], { type: mime }),
     raw_filename,
     ext,
+    musicID,
   );
 
   return {
@@ -81,19 +89,25 @@ export async function Decrypt(file: Blob, raw_filename: string, raw_ext: string)
 
 export class QmcDecoder {
   private static readonly BYTE_COMMA = ','.charCodeAt(0);
-  file: Uint8Array;
-  size: number;
-  decoded: boolean = false;
-  audioSize?: number;
-  cipher?: QmcStreamCipher;
+  private readonly file: Uint8Array;
+  private readonly size: number;
+  private decoded: boolean = false;
+  private audioSize?: number;
+  private cipher?: QmcStreamCipher;
 
-  constructor(file: Uint8Array) {
+  public constructor(file: Uint8Array) {
     this.file = file;
     this.size = file.length;
     this.searchKey();
   }
 
-  decrypt(): Uint8Array {
+  private _songID?: number;
+
+  public get songID() {
+    return this._songID;
+  }
+
+  public decrypt(): Uint8Array {
     if (!this.cipher) {
       throw new Error('no cipher found');
     }
@@ -118,9 +132,20 @@ export class QmcDecoder {
       const sizeView = new DataView(sizeBuf.buffer, sizeBuf.byteOffset);
       const keySize = sizeView.getUint32(0, false);
       this.audioSize = this.size - keySize - 8;
+
       const rawKey = this.file.subarray(this.audioSize, this.size - 8);
       const keyEnd = rawKey.findIndex((v) => v == QmcDecoder.BYTE_COMMA);
+      if (keyEnd < 0) {
+        throw new Error('invalid key: search raw key failed');
+      }
       this.setCipher(rawKey.subarray(0, keyEnd));
+
+      const idBuf = rawKey.subarray(keyEnd + 1);
+      const idEnd = idBuf.findIndex((v) => v == QmcDecoder.BYTE_COMMA);
+      if (keyEnd < 0) {
+        throw new Error('invalid key: search song id failed');
+      }
+      this._songID = parseInt(textEnc.decode(idBuf.subarray(0, idEnd)), 10);
     } else {
       const sizeView = new DataView(last4Byte.buffer, last4Byte.byteOffset);
       const keySize = sizeView.getUint32(0, true);

src/decrypt/qmc_wasm.ts

@@ -1,5 +1,6 @@
 import QMCCryptoModule from '@jixun/qmc2-crypto/QMC2-wasm-bundle';
 import { MergeUint8Array } from '@/utils/MergeUint8Array';
+import { QMCCrypto } from '@jixun/qmc2-crypto/QMCCrypto';
 
 // 检测文件末端使用的缓冲区大小
 const DETECTION_SIZE = 40;
@@ -7,16 +8,31 @@ const DETECTION_SIZE = 40;
 // 每次处理 2M 的数据
 const DECRYPTION_BUF_SIZE = 2 * 1024 * 1024;
 
+export interface QMC2DecryptionResult {
+  success: boolean;
+  data: Uint8Array;
+  songId: string | number;
+  error: string;
+}
+
 /**
  * 解密一个 QMC2 加密的文件。
  *
  * 如果检测并解密成功，返回解密后的 Uint8Array 数据。
  * @param  {ArrayBuffer} mggBlob 读入的文件 Blob
- * @return {Promise<Uint8Array|false>}
  */
-export async function DecryptQMCWasm(mggBlob: ArrayBuffer) {
+export async function DecryptQMCWasm(mggBlob: ArrayBuffer): Promise<QMC2DecryptionResult> {
+  const result: QMC2DecryptionResult = { success: false, data: new Uint8Array(), songId: 0, error: '' };
+
   // 初始化模组
-  const QMCCrypto = await QMCCryptoModule();
+  let QMCCrypto: QMCCrypto;
+
+  try {
+    QMCCrypto = await QMCCryptoModule();
+  } catch (err: any) {
+    result.error = err?.message || 'wasm 加载失败';
+    return result;
+  }
 
   // 申请内存块，并文件末端数据到 WASM 的内存堆
   const detectionBuf = new Uint8Array(mggBlob.slice(-DETECTION_SIZE));
@@ -34,12 +50,26 @@ export async function DecryptQMCWasm(mggBlob: ArrayBuffer) {
   const position = QMCCrypto.getValue(pDetectionResult, 'i32');
   const len = QMCCrypto.getValue(pDetectionResult + 4, 'i32');
 
+  result.success = detectOK;
+  result.error = QMCCrypto.UTF8ToString(
+    pDetectionResult + QMCCrypto.offsetof_error_msg(),
+    QMCCrypto.sizeof_error_msg(),
+  );
+  const songId = QMCCrypto.UTF8ToString(pDetectionResult + QMCCrypto.offsetof_song_id(), QMCCrypto.sizeof_song_id());
+  if (!songId) {
+    console.debug('qmc2-wasm: songId not found');
+  } else if (/^\d+$/.test(songId)) {
+    result.songId = songId;
+  } else {
+    console.warn('qmc2-wasm: Invalid songId: %s', songId);
+  }
+
   // 释放内存
   QMCCrypto._free(pDetectionBuf);
   QMCCrypto._free(pDetectionResult);
 
   if (!detectOK) {
-    return false;
+    return result;
   }
 
   // 计算解密后文件的大小。
@@ -75,5 +105,7 @@ export async function DecryptQMCWasm(mggBlob: ArrayBuffer) {
   QMCCrypto._free(buf);
   hCrypto.delete();
 
-  return MergeUint8Array(decryptedParts);
+  result.data = MergeUint8Array(decryptedParts);
+
+  return result;
 }