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fix: treat qmcflac/qmcogg as QMCv2 and fallback to QMCv1

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(cherry picked from commit 41e588e9864801897fa13eb96a1764baaa5a4ab5)
This commit is contained in:
鲁树人 2021-12-15 22:07:05 +00:00
parent d199647308
commit fb33e80484
2 changed files with 23 additions and 11 deletions
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29
src/decrypt/qmc.ts
View File

@ -27,11 +27,14 @@ export const HandlerMap: { [key: string]: Handler } = {
"mflac": {ext: "flac", version: 2},
"mflac0": {ext: "flac", version: 2},
// qmcflac / qmcogg:
// 有可能是 v2 加密但混用同一个后缀名。
"qmcflac": {ext: "flac", version: 2},
"qmcogg": {ext: "ogg", version: 2},
"qmc0": {ext: "mp3", version: 1},
"qmc2": {ext: "ogg", version: 1},
"qmc3": {ext: "mp3", version: 1},
"qmcogg": {ext: "ogg", version: 1},
"qmcflac": {ext: "flac", version: 1},
"bkcmp3": {ext: "mp3", version: 1},
"bkcflac": {ext: "flac", version: 1},
"tkm": {ext: "m4a", version: 1},
@ -45,16 +48,26 @@ export const HandlerMap: { [key: string]: Handler } = {
export async function Decrypt(file: Blob, raw_filename: string, raw_ext: string): Promise<DecryptResult> {
if (!(raw_ext in HandlerMap)) throw `Qmc cannot handle type: ${raw_ext}`;
const handler = HandlerMap[raw_ext];
let { version } = handler;
const fileBuffer = await GetArrayBuffer(file);
let musicDecoded: Uint8Array;
if (handler.version === 1) {
let musicDecoded: Uint8Array|undefined;
if (version === 2) {
const v2Decrypted = await DecryptQMCv2(fileBuffer);
// 如果 v2 检测失败，降级到 v1 再尝试一次
if (v2Decrypted) {
musicDecoded = v2Decrypted;
} else {
version = 1;
}
}
if (version === 1) {
const seed = QmcMaskGetDefault();
musicDecoded = seed.Decrypt(new Uint8Array(fileBuffer));
} else if (handler.version === 2) {
musicDecoded = await DecryptQMCv2(fileBuffer);
} else {
throw new Error(`不支持的加密版本: ${handler.version} (${raw_ext})`);
} else if (!musicDecoded) {
throw new Error(`解密失败: ${raw_ext}`);
}
const ext = SniffAudioExt(musicDecoded, handler.ext);

5
src/decrypt/qmcv2.ts
View File

@ -28,7 +28,7 @@ function MergeUint8Array(array: Uint8Array[]): Uint8Array {
* 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
* @param {string} name 文件名
* @return {Promise<Uint8Array|null>}
* @return {Promise<Uint8Array|false>}
*/
export async function DecryptQMCv2(mggBlob: ArrayBuffer) {
// 初始化模组
@ -53,14 +53,13 @@ export async function DecryptQMCv2(mggBlob: ArrayBuffer) {
// (pos: i32; len: i32; error: char[??])
const position = QMCCrypto.getValue(pDetectionResult, "i32");
const len = QMCCrypto.getValue(pDetectionResult + 4, "i32");
const detectionError = QMCCrypto.UTF8ToString(pDetectionResult + 8);
// 释放内存
QMCCrypto._free(pDetectionBuf);
QMCCrypto._free(pDetectionResult);
if (!detectOK) {
throw new Error("解密失败: \n " + detectionError);
return false;
}
// 计算解密后文件的大小。