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init: dec-music 项目初始化

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pgmsoul
2026-05-23 12:55:48 +08:00
commit 21045d0aad
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.gitignore
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# 编译产物
*.exe
*.exe~
*.dll
*.so
*.dylib
# IDE
.idea/
*.iml
*.swp
*.swo
*~
# SSH 密钥（私钥）
id_*
!id_*.pub
*.pem
*.ppk
# 测试数据文件
**/testdata/*.bin
*.out
*.test
coverage.*
# 系统文件
Thumbs.db
.DS_Store
# Go 工作区（如果将来使用）
go.work
go.work.sum
README.md
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# dec-music
## 作为库使用
模块路径：`jsuse.com/dev/dec-music`
对外包名：`music`
### API（与历史版本兼容）
```go
import "jsuse.com/dev/dec-music"
// 批量解密目录（递归子目录）
err := music.DecryptProcess(inputDir, outputDir, noSubOutput, onProcess)
// 解密单个文件
err := music.DecryptFile(inputFile, outputDir, noSubOutput, onProcess)
```
| 符号 | 说明 |
|------|------|
| `music.DecryptProcess` | 遍历 `inputDir` 下媒体文件并解密到 `outputDir` |
| `music.DecryptFile` | 只处理一个文件 |
| `music.OnProcess` | 可选回调 `func(src, dst, err string)`，`err` 为空表示成功 |
| `music.ErrNoDecoder` | 无可用解密器时的错误文案常量 |
`noSubOutput == false` 时，输出目录会保留相对子目录结构；为 `true` 时所有文件平铺在 `outputDir` 下。
### 示例
```go
package main
import (
"fmt"
"jsuse.com/dev/dec-music"
)
func main() {
err := music.DecryptProcess(`D:\Music\encrypted`, `D:\Music\decrypted`, false,
func(src, dst, errMsg string) {
if errMsg != "" {
fmt.Println("失败:", src, errMsg)
return
}
fmt.Println("成功:", src, "->", dst)
})
if err != nil {
panic(err)
}
}
```
## 命令行工具（本地测试）
CLI 位于 `cmd/dec-music`，依赖 `urfave/cli`，与库分离。
**不要在仓库根目录**对 `.` 执行 `go build -o xxx.exe`：根目录是 `package music`（库），没有 `main`。那样即使生成名为 `.exe` 的文件，也不是 Windows 可执行程序，运行会提示“不是有效的 Win32 应用”等。
```bash
# 正确：编译命令行程序
go build -o dec-music.exe ./cmd/dec-music
# 根目录仅校验库能否编译（不会在目录里生成可运行的 exe）
go build .
```
无参数运行 `dec-music.exe` 会打印用法（等同 `--help`）。
### 用法
```text
dec-music [选项] [输入路径]
选项:
-i, --input <路径> 输入文件或目录（默认当前目录）
-o, --output <路径> 输出目录（默认与输入相同）
--no-sub-output 输出文件不保留子目录结构
--skip-noop 跳过已是明文的音频（mp3/flac 等透传解码器）
--overwrite 覆盖已存在的输出文件
--supported-ext 列出支持的加密扩展名并退出
--qmc-mmkv <文件> macOS QQ 音乐 MMKV 密钥库路径
--qmc-mmkv-key <密钥> 加密 MMKV 的 AES 密钥（可选）
```
### 示例
```bash
# 解密当前目录到 ./out
dec-music -i . -o ./out
# 解密单个文件
dec-music -i song.ncm -o ./out
# 查看支持的扩展名
dec-music --supported-ext
# macOS QQ 音乐：指定 MMKV（可选）
dec-music -i ~/Music --qmc-mmkv "/path/to/MMKVStreamEncryptId"
```
成功时终端会打印彩色行：`操作成功: 源 -> 目标`（由 `log` 包输出）。
## 支持的格式
| 平台 | 常见扩展名 |
|------|------------|
| 网易云 | `.ncm` |
| QQ / 腾讯 | `.qmc0` `.qmc3` `.qmcflac` `.mgg` `.mflac` `.tkm` 等 |
| 酷狗 | `.kgm` `.kgma` `.vpr` |
| 酷我 | `.kwm` |
| 喜马拉雅 | `.x2m` `.x3m` `.xm` |
| 虾米等 | `.xm` `.wav` `.mp3`（部分） |
完整列表以 `--supported-ext` 或 `decrypt.SupportedExtensions()` 为准。
## 项目结构
```text
dec-music/
├── decrypt.go # package music：对外 API
├── decrypt/ # 各平台解密实现（内部）
├── mmkv/ # QQ Mac MMKV 密钥（内部，darwin）
├── internal/
│ ├── crypto/ # AES 等
│ ├── sniff/ # 输出格式嗅探
│ └── fileutil/ # 媒体文件判断
├── log/ # 可选彩色日志（CLI 使用）
└── cmd/dec-music/ # 命令行
```
## 依赖说明
| 模块 | 用途 |
|------|------|
| （根模块库） | 仅标准库；`internal/tea` 为 QQ 密钥派生（源自 golang.org/x/crypto/tea，BSD） |
| `cmd/dec-music` | 额外需要 `github.com/urfave/cli/v2` |
MMKV 的 protobuf 线格式解析已内置在 `mmkv/internal`，不依赖 `google.golang.org/protobuf`。
## 开发
```bash
go build .
go test ./decrypt/...
go build ./cmd/dec-music
```
## 许可
与项目原有许可保持一致。`internal/tea` 摘自 golang.org/x/crypto（BSD），见该目录内源文件注释。
D:\Media\Kugou\Download\KugouMusic\张蔷 - 夜猫.kgma
cmd/dec-music/main.go
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package main
import (
"errors"
"fmt"
"os"
"path/filepath"
"sort"
"github.com/urfave/cli/v2"
"jsuse.com/dev/dec-music"
"jsuse.com/dev/dec-music/decrypt"
"jsuse.com/dev/dec-music/decrypt/qmc"
"jsuse.com/dev/dec-music/log"
_ "jsuse.com/dev/dec-music/decrypt/kgm"
_ "jsuse.com/dev/dec-music/decrypt/kwm"
_ "jsuse.com/dev/dec-music/decrypt/ncm"
_ "jsuse.com/dev/dec-music/decrypt/qmc"
_ "jsuse.com/dev/dec-music/decrypt/tm"
_ "jsuse.com/dev/dec-music/decrypt/xiami"
_ "jsuse.com/dev/dec-music/decrypt/ximalaya"
)
func main() {
app := newApp()
if len(os.Args) <= 1 {
_ = app.Run([]string{os.Args[0], "--help"})
return
}
if err := app.Run(os.Args); err != nil {
_, _ = fmt.Fprintln(os.Stderr, err)
os.Exit(1)
}
}
func newApp() *cli.App {
return &cli.App{
Name: "dec-music",
Usage: "Decrypt encrypted music files (ncm, qmc, kgm, kwm, tm, ximalaya, etc.)",
Flags: []cli.Flag{
&cli.StringFlag{Name: "input", Aliases: []string{"i"}, Usage: "input file or directory"},
&cli.StringFlag{Name: "output", Aliases: []string{"o"}, Usage: "output directory (default: input directory)"},
&cli.BoolFlag{Name: "no-sub-output", Usage: "write outputs flat into output directory"},
&cli.BoolFlag{Name: "skip-noop", Usage: "skip plain (already decrypted) audio files"},
&cli.BoolFlag{Name: "overwrite", Usage: "overwrite existing output files"},
&cli.BoolFlag{Name: "supported-ext", Usage: "list supported extensions and exit"},
&cli.StringFlag{Name: "qmc-mmkv", Usage: "QQ Music MMKV vault file (macOS)"},
&cli.StringFlag{Name: "qmc-mmkv-key", Usage: "AES key for encrypted MMKV vault"},
},
Action: run,
}
}
func run(c *cli.Context) error {
if c.Bool("supported-ext") {
printSupportedExtensions()
return nil
}
input := c.String("input")
if input == "" {
switch c.Args().Len() {
case 0:
return cli.ShowAppHelp(c) // e.g. only flags, no input path
case 1:
input = c.Args().Get(0)
default:
return errors.New("specify one input file or directory")
}
}
input, err := filepath.Abs(input)
if err != nil {
return fmt.Errorf("resolve input: %w", err)
}
stat, err := os.Stat(input)
if err != nil {
return err
}
output := c.String("output")
if output == "" {
if stat.IsDir() {
output = input
} else {
output = filepath.Dir(input)
}
}
if err := ensureDir(output); err != nil {
return err
}
logger := log.New()
if mmkvPath := c.String("qmc-mmkv"); mmkvPath != "" {
if err := qmc.OpenMMKVCLI(mmkvPath, c.String("qmc-mmkv-key"), logger); err != nil {
return err
}
}
if stat.IsDir() {
return music.DecryptProcessCLI(input, output, c.Bool("no-sub-output"), c.Bool("skip-noop"), c.Bool("overwrite"))
}
return music.DecryptFileCLI(input, output, c.Bool("no-sub-output"), c.Bool("skip-noop"), c.Bool("overwrite"))
}
func ensureDir(path string) error {
stat, err := os.Stat(path)
if err != nil {
if errors.Is(err, os.ErrNotExist) {
return os.MkdirAll(path, 0o755)
}
return err
}
if !stat.IsDir() {
return errors.New("output must be a directory")
}
return nil
}
func printSupportedExtensions() {
extSet := decrypt.SupportedExtensions()
exts := make([]string, 0, len(extSet))
for ext := range extSet {
exts = append(exts, ext)
}
sort.Strings(exts)
for _, ext := range exts {
fmt.Printf("%s: %d\n", ext, extSet[ext])
}
}
decrypt.go
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package music
import (
"bytes"
"errors"
"fmt"
"io"
"os"
"path/filepath"
"strings"
"jsuse.com/dev/dec-music/decrypt"
"jsuse.com/dev/dec-music/internal/fileutil"
"jsuse.com/dev/dec-music/internal/sniff"
"jsuse.com/dev/dec-music/log"
_ "jsuse.com/dev/dec-music/decrypt/kgm"
_ "jsuse.com/dev/dec-music/decrypt/kwm"
_ "jsuse.com/dev/dec-music/decrypt/ncm"
_ "jsuse.com/dev/dec-music/decrypt/qmc"
_ "jsuse.com/dev/dec-music/decrypt/tm"
_ "jsuse.com/dev/dec-music/decrypt/xiami"
_ "jsuse.com/dev/dec-music/decrypt/ximalaya"
)
const (
// ErrNoDecoder is returned when no decoder can handle the file.
ErrNoDecoder = "no suitable decoder"
)
var defaultLogger = log.New()
// OnProcess is called after each file is processed (err empty on success).
type OnProcess func(src, dst, err string)
// DecryptFile decrypts a single file into outputDir.
func DecryptFile(inputFile, outputDir string, noSubOutput bool, onProcess OnProcess) error {
inputDir, err := filepath.Abs(filepath.Dir(inputFile))
if err != nil {
return err
}
outDir, err := filepath.Abs(outputDir)
if err != nil {
return err
}
return decryptProcessFile(inputFile, outDir, inputDir, noSubOutput, false, false, onProcess)
}
func decryptProcessFile(inputFile, outputDir, inputDir string, noSubOutput, skipNoop, overwrite bool, onProcess OnProcess) error {
proc := &processor{
onProcess: onProcess,
logger: defaultLogger,
inputDir: inputDir,
outputDir: outputDir,
singleOutput: noSubOutput,
skipNoopDecoder: skipNoop,
overwriteOutput: overwrite,
}
return proc.processFile(inputFile)
}
// DecryptProcess decrypts encrypted media under inputDir into outputDir.
// When noSubOutput is false, relative subdirectory structure is preserved.
func DecryptProcess(inputDir, outputDir string, noSubOutput bool, onProcess OnProcess) error {
return decryptProcessEx(inputDir, outputDir, noSubOutput, false, false, onProcess)
}
// DecryptProcessCLI is like DecryptProcess but accepts skip-noop and overwrite (CLI helper).
func DecryptProcessCLI(inputDir, outputDir string, noSubOutput, skipNoop, overwrite bool) error {
return decryptProcessEx(inputDir, outputDir, noSubOutput, skipNoop, overwrite, nil)
}
// DecryptFileCLI decrypts one file (CLI helper).
func DecryptFileCLI(inputFile, outputDir string, noSubOutput, skipNoop, overwrite bool) error {
inputDir, err := filepath.Abs(filepath.Dir(inputFile))
if err != nil {
return err
}
outDir, err := filepath.Abs(outputDir)
if err != nil {
return err
}
return decryptProcessFile(inputFile, outDir, inputDir, noSubOutput, skipNoop, overwrite, nil)
}
func decryptProcessEx(inputDir, outputDir string, noSubOutput, skipNoop, overwrite bool, onProcess OnProcess) error {
proc := &processor{
onProcess: onProcess,
logger: defaultLogger,
inputDir: inputDir,
outputDir: outputDir,
singleOutput: noSubOutput,
skipNoopDecoder: skipNoop,
overwriteOutput: overwrite,
}
return proc.processDir(inputDir)
}
type processor struct {
onProcess OnProcess
logger *log.Logger
inputDir string
outputDir string
skipNoopDecoder bool
overwriteOutput bool
singleOutput bool
}
func (p *processor) processDir(inputDir string) error {
items, err := os.ReadDir(inputDir)
if err != nil {
return err
}
var lastError error
for _, item := range items {
if strings.EqualFold(item.Name(), "temp") {
continue
}
filePath := filepath.Join(inputDir, item.Name())
if item.IsDir() {
if err = p.processDir(filePath); err != nil {
lastError = err
}
continue
}
if !fileutil.IsMediaFile(item.Name()) {
continue
}
if err = p.processFile(filePath); err != nil {
lastError = err
if p.logger != nil {
p.logger.Error("conversion failed:", item.Name(), err)
}
}
}
if lastError != nil {
return fmt.Errorf("last error: %w", lastError)
}
return nil
}
func (p *processor) processFile(filePath string) error {
factories := decrypt.GetDecoder(filePath, p.skipNoopDecoder)
if len(factories) == 0 {
return errors.New("skipping while no suitable decoder")
}
if err := p.process(filePath, factories); err != nil {
if err.Error() == ErrNoDecoder {
// Fallback: copy as-is when no decoder matches (keeps original extension).
fallbackDst := filepath.Join(p.outputDir, filepath.Base(filePath))
copyErr := p.copyFile(filePath, fallbackDst)
if copyErr == nil {
p.logResult(filePath, fallbackDst)
}
return copyErr
}
return err
}
return nil
}
func (p *processor) logResult(inputFile, outPath string) {
inputRelDir, err := filepath.Rel(p.inputDir, filepath.Dir(inputFile))
dstName := filepath.Base(outPath)
if !p.singleOutput {
dstName = filepath.Join(inputRelDir, filepath.Base(outPath))
}
srcName := filepath.Join(inputRelDir, filepath.Base(inputFile))
if err != nil {
if p.onProcess != nil {
p.onProcess(srcName, dstName, err.Error())
}
return
}
if p.onProcess != nil {
p.onProcess(srcName, dstName, "")
} else {
log.PrintSuccess(srcName, dstName)
}
}
func (p *processor) copyFile(src, dst string) error {
sourceFile, err := os.Open(src)
if err != nil {
return err
}
defer sourceFile.Close()
destFile, err := os.OpenFile(dst, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0644)
if err != nil {
return err
}
defer destFile.Close()
_, err = io.Copy(destFile, sourceFile)
return err
}
func (p *processor) findDecoder(factories []decrypt.Factory, params *decrypt.DecoderParams) (decrypt.Decoder, *decrypt.Factory, error) {
for i := range factories {
factory := &factories[i]
dec := factory.Create(params)
if err := dec.Validate(); err == nil {
return dec, factory, nil
}
}
return nil, nil, errors.New("no any decoder can resolve the file")
}
func (p *processor) process(inputFile string, factories []decrypt.Factory) error {
file, err := os.Open(inputFile)
if err != nil {
return err
}
defer file.Close()
params := &decrypt.DecoderParams{
Reader: file,
Extension: filepath.Ext(inputFile),
FilePath: inputFile,
Logger: p.logger,
}
dec, factory, err := p.findDecoder(factories, params)
if err != nil {
return errors.New(ErrNoDecoder)
}
header := bytes.NewBuffer(nil)
if _, err = io.CopyN(header, dec, 64); err != nil {
return fmt.Errorf("read header failed: %w", err)
}
audio := io.MultiReader(header, dec)
audioExt := sniff.AudioExtensionWithFallback(header.Bytes(), ".mp3")
inputRelDir, err := filepath.Rel(p.inputDir, filepath.Dir(inputFile))
if err != nil {
return fmt.Errorf("get relative dir failed: %w", err)
}
inFilename := strings.TrimSuffix(filepath.Base(inputFile), factory.Suffix)
outFolder := p.outputDir
if !p.singleOutput {
outFolder = filepath.Join(p.outputDir, inputRelDir)
}
if err = os.MkdirAll(outFolder, os.ModePerm); err != nil {
return err
}
outPath := filepath.Join(outFolder, inFilename+audioExt)
if !p.overwriteOutput {
if _, err := os.Stat(outPath); err == nil {
if p.logger != nil {
p.logger.Info("output already exists, skipped:", outPath)
}
return nil
} else if !errors.Is(err, os.ErrNotExist) {
return fmt.Errorf("stat output file failed: %w", err)
}
}
outFile, err := os.OpenFile(outPath, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0644)
if err != nil {
return err
}
defer outFile.Close()
if _, err = io.Copy(outFile, audio); err != nil {
return err
}
p.logResult(inputFile, outPath)
return nil
}
decrypt/dispatch.go
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package decrypt
import (
"io"
"path/filepath"
"strings"
"jsuse.com/dev/dec-music/log"
)
// DecoderParams configures a decoder instance.
type DecoderParams struct {
Reader io.ReadSeeker
Extension string
FilePath string
Logger *log.Logger
}
// Factory creates decoders for a registered file suffix.
type Factory struct {
Suffix string
Noop bool
Create func(*DecoderParams) Decoder
}
var registry []Factory
// RegisterDecoder registers a file suffix handler (called from format init).
func RegisterDecoder(ext string, noop bool, fn func(*DecoderParams) Decoder) {
registry = append(registry, Factory{
Noop: noop, Create: fn, Suffix: "." + strings.TrimPrefix(ext, "."),
})
}
// GetDecoder returns matching factories for a file name.
func GetDecoder(filename string, skipNoop bool) []Factory {
var result []Factory
name := strings.ToLower(filepath.Base(filename))
for _, dec := range registry {
if !strings.HasSuffix(name, dec.Suffix) {
continue
}
if skipNoop && dec.Noop {
continue
}
result = append(result, dec)
}
return result
}
// SupportedExtensions returns registered suffixes and handler counts.
func SupportedExtensions() map[string]int {
extSet := make(map[string]int)
for _, f := range registry {
ext := strings.TrimPrefix(f.Suffix, ".")
extSet[ext]++
}
return extSet
}
decrypt/interface.go
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package decrypt
import "io"
// StreamDecoder decrypts audio stream bytes in place.
type StreamDecoder interface {
Decrypt(buf []byte, offset int)
}
// Decoder decrypts one encrypted media file.
type Decoder interface {
Validate() error
io.Reader
}
decrypt/kgm/kgm.go
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package kgm
import (
"fmt"
"io"
"jsuse.com/dev/dec-music/decrypt"
)
type decoder struct {
rd io.ReadSeeker
cipher decrypt.StreamDecoder
offset int
header header
}
func newDecoder(p *decrypt.DecoderParams) decrypt.Decoder {
return &decoder{rd: p.Reader}
}
// Validate checks if the file is a valid Kugou (.kgm, .vpr, .kgma) file.
// rd will be seeked to the beginning of the encrypted audio.
func (d *decoder) Validate() (err error) {
if err := d.header.FromFile(d.rd); err != nil {
return err
}
// TODO; validate crypto version
switch d.header.CryptoVersion {
case 3:
d.cipher, err = newKgmCryptoV3(&d.header)
if err != nil {
return fmt.Errorf("kgm init crypto v3: %w", err)
}
default:
return fmt.Errorf("kgm: unsupported crypto version %d", d.header.CryptoVersion)
}
// prepare for read
if _, err := d.rd.Seek(int64(d.header.AudioOffset), io.SeekStart); err != nil {
return fmt.Errorf("kgm seek to audio: %w", err)
}
return nil
}
func (d *decoder) Read(buf []byte) (int, error) {
n, err := d.rd.Read(buf)
if n > 0 {
d.cipher.Decrypt(buf[:n], d.offset)
d.offset += n
}
return n, err
}
func init() {
// Kugou
decrypt.RegisterDecoder("kgm", false , newDecoder)
decrypt.RegisterDecoder("kgma", false , newDecoder)
// Viper
decrypt.RegisterDecoder("vpr", false , newDecoder)
// Kugou Android
decrypt.RegisterDecoder("kgm.flac", false , newDecoder)
decrypt.RegisterDecoder("vpr.flac", false , newDecoder)
}
decrypt/kgm/kgm_header.go
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package kgm
import (
"bytes"
"encoding/binary"
"errors"
"fmt"
"io"
)
var (
vprHeader = []byte{
0x05, 0x28, 0xBC, 0x96, 0xE9, 0xE4, 0x5A, 0x43,
0x91, 0xAA, 0xBD, 0xD0, 0x7A, 0xF5, 0x36, 0x31,
}
kgmHeader = []byte{
0x7C, 0xD5, 0x32, 0xEB, 0x86, 0x02, 0x7F, 0x4B,
0xA8, 0xAF, 0xA6, 0x8E, 0x0F, 0xFF, 0x99, 0x14,
}
ErrKgmMagicHeader = errors.New("kgm magic header not matched")
)
// header is the header of a KGM file.
type header struct {
MagicHeader []byte // 0x00-0x0f: magic header
AudioOffset uint32 // 0x10-0x13: offset of audio data
CryptoVersion uint32 // 0x14-0x17: crypto version
CryptoSlot uint32 // 0x18-0x1b: crypto key slot
CryptoTestData []byte // 0x1c-0x2b: crypto test data
CryptoKey []byte // 0x2c-0x3b: crypto key
}
func (h *header) FromFile(rd io.ReadSeeker) error {
if _, err := rd.Seek(0, io.SeekStart); err != nil {
return fmt.Errorf("kgm seek start: %w", err)
}
buf := make([]byte, 0x3c)
if _, err := io.ReadFull(rd, buf); err != nil {
return fmt.Errorf("kgm read header: %w", err)
}
return h.FromBytes(buf)
}
func (h *header) FromBytes(buf []byte) error {
if len(buf) < 0x3c {
return errors.New("invalid kgm header length")
}
h.MagicHeader = buf[:0x10]
if !bytes.Equal(kgmHeader, h.MagicHeader) && !bytes.Equal(vprHeader, h.MagicHeader) {
return ErrKgmMagicHeader
}
h.AudioOffset = binary.LittleEndian.Uint32(buf[0x10:0x14])
h.CryptoVersion = binary.LittleEndian.Uint32(buf[0x14:0x18])
h.CryptoSlot = binary.LittleEndian.Uint32(buf[0x18:0x1c])
h.CryptoTestData = buf[0x1c:0x2c]
h.CryptoKey = buf[0x2c:0x3c]
return nil
}
decrypt/kgm/kgm_v3.go
+55
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@@ -0,0 +1,55 @@
package kgm
import (
"crypto/md5"
"fmt"
"jsuse.com/dev/dec-music/decrypt"
)
// kgmCryptoV3 is kgm file crypto v3
type kgmCryptoV3 struct {
slotBox []byte
fileBox []byte
}
var kgmV3Slot2Key = map[uint32][]byte{
1: {0x6C, 0x2C, 0x2F, 0x27},
}
func newKgmCryptoV3(header *header) (decrypt.StreamDecoder, error) {
c := &kgmCryptoV3{}
slotKey, ok := kgmV3Slot2Key[header.CryptoSlot]
if !ok {
return nil, fmt.Errorf("kgm3: unknown crypto slot %d", header.CryptoSlot)
}
c.slotBox = kugouMD5(slotKey)
c.fileBox = append(kugouMD5(header.CryptoKey), 0x6b)
return c, nil
}
func (d *kgmCryptoV3) Decrypt(b []byte, offset int) {
for i := 0; i < len(b); i++ {
b[i] ^= d.fileBox[(offset+i)%len(d.fileBox)]
b[i] ^= b[i] << 4
b[i] ^= d.slotBox[(offset+i)%len(d.slotBox)]
b[i] ^= xorCollapseUint32(uint32(offset + i))
}
}
func xorCollapseUint32(i uint32) byte {
return byte(i) ^ byte(i>>8) ^ byte(i>>16) ^ byte(i>>24)
}
func kugouMD5(b []byte) []byte {
digest := md5.Sum(b)
ret := make([]byte, 16)
for i := 0; i < md5.Size; i += 2 {
ret[i] = digest[14-i]
ret[i+1] = digest[14-i+1]
}
return ret
}
decrypt/kwm/kwm.go
+99
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@@ -0,0 +1,99 @@
package kwm
import (
"bytes"
"errors"
"fmt"
"io"
"strconv"
"strings"
"unicode"
"jsuse.com/dev/dec-music/decrypt"
)
const magicHeader1 = "yeelion-kuwo-tme"
const magicHeader2 = "yeelion-kuwo\x00\x00\x00\x00"
const keyPreDefined = "MoOtOiTvINGwd2E6n0E1i7L5t2IoOoNk"
type decoder struct {
rd io.ReadSeeker
cipher decrypt.StreamDecoder
offset int
outputExt string
bitrate int
}
func (d *decoder) GetAudioExt() string {
return "." + d.outputExt
}
func newDecoder(p *decrypt.DecoderParams) decrypt.Decoder {
return &decoder{rd: p.Reader}
}
// Validate checks if the file is a valid Kuwo .kw file.
// rd will be seeked to the beginning of the encrypted audio.
func (d *decoder) Validate() error {
header := make([]byte, 0x400) // kwm header is fixed to 1024 bytes
_, err := io.ReadFull(d.rd, header)
if err != nil {
return fmt.Errorf("kwm read header: %w", err)
}
// check magic header, 0x00 - 0x0F
magicHeader := header[:0x10]
if !bytes.Equal([]byte(magicHeader1), magicHeader) &&
!bytes.Equal([]byte(magicHeader2), magicHeader) {
return errors.New("kwm magic header not matched")
}
d.cipher = newKwmCipher(header[0x18:0x20]) // Crypto Key, 0x18 - 0x1F
d.bitrate, d.outputExt = parseBitrateAndType(header[0x30:0x38]) // Bitrate & File Extension, 0x30 - 0x38
return nil
}
func parseBitrateAndType(header []byte) (int, string) {
tmp := strings.TrimRight(string(header), "\x00")
sep := strings.IndexFunc(tmp, func(r rune) bool {
return !unicode.IsDigit(r)
})
bitrate, _ := strconv.Atoi(tmp[:sep]) // just ignore the error
outputExt := strings.ToLower(tmp[sep:])
return bitrate, outputExt
}
func (d *decoder) Read(b []byte) (int, error) {
n, err := d.rd.Read(b)
if n > 0 {
d.cipher.Decrypt(b[:n], d.offset)
d.offset += n
}
return n, err
}
func padOrTruncate(raw string, length int) string {
lenRaw := len(raw)
out := raw
if lenRaw == 0 {
out = string(make([]byte, length))
} else if lenRaw > length {
out = raw[:length]
} else if lenRaw < length {
_tmp := make([]byte, 32)
for i := 0; i < 32; i++ {
_tmp[i] = raw[i%lenRaw]
}
out = string(_tmp)
}
return out
}
func init() {
// Kuwo Mp3/Flac
decrypt.RegisterDecoder("kwm", false, newDecoder)
}
decrypt/kwm/kwm_cipher.go
+31
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@@ -0,0 +1,31 @@
package kwm
import (
"encoding/binary"
"strconv"
)
type kwmCipher struct {
mask []byte
}
func newKwmCipher(key []byte) *kwmCipher {
return &kwmCipher{mask: generateMask(key)}
}
func generateMask(key []byte) []byte {
keyInt := binary.LittleEndian.Uint64(key)
keyStr := strconv.FormatUint(keyInt, 10)
keyStrTrim := padOrTruncate(keyStr, 32)
mask := make([]byte, 32)
for i := 0; i < 32; i++ {
mask[i] = keyPreDefined[i] ^ keyStrTrim[i]
}
return mask
}
func (c kwmCipher) Decrypt(buf []byte, offset int) {
for i := range buf {
buf[i] ^= c.mask[(offset+i)&0x1F] // equivalent: [i % 32]
}
}
decrypt/ncm/ncm.go
+147
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@@ -0,0 +1,147 @@
package ncm
import (
"bytes"
"encoding/binary"
"errors"
"fmt"
"io"
"jsuse.com/dev/dec-music/decrypt"
"jsuse.com/dev/dec-music/internal/crypto"
)
const magicHeader = "CTENFDAM"
var (
keyCore = []byte{
0x68, 0x7a, 0x48, 0x52, 0x41, 0x6d, 0x73, 0x6f,
0x35, 0x6b, 0x49, 0x6e, 0x62, 0x61, 0x78, 0x57,
}
keyMeta = []byte{
0x23, 0x31, 0x34, 0x6C, 0x6A, 0x6B, 0x5F, 0x21,
0x5C, 0x5D, 0x26, 0x30, 0x55, 0x3C, 0x27, 0x28,
}
)
func newDecoder(p *decrypt.DecoderParams) decrypt.Decoder {
return &decoder{rd: p.Reader}
}
type decoder struct {
rd io.ReadSeeker
offset int
cipher decrypt.StreamDecoder
}
func (d *decoder) Validate() error {
if err := d.validateMagicHeader(); err != nil {
return err
}
if _, err := d.rd.Seek(2, io.SeekCurrent); err != nil {
return fmt.Errorf("ncm seek file: %w", err)
}
keyData, err := d.readKeyData()
if err != nil {
return err
}
if err := d.skipMetaData(); err != nil {
return fmt.Errorf("ncm skip meta: %w", err)
}
if _, err := d.rd.Seek(5, io.SeekCurrent); err != nil {
return fmt.Errorf("ncm seek gap: %w", err)
}
if err := d.skipCoverData(); err != nil {
return fmt.Errorf("ncm skip cover: %w", err)
}
d.cipher = newNcmCipher(keyData)
return nil
}
func (d *decoder) validateMagicHeader() error {
header := make([]byte, len(magicHeader))
if _, err := d.rd.Read(header); err != nil {
return fmt.Errorf("ncm read magic header: %w", err)
}
if !bytes.Equal([]byte(magicHeader), header) {
return errors.New("ncm magic header not match")
}
return nil
}
func (d *decoder) readKeyData() ([]byte, error) {
bKeyLen := make([]byte, 4)
if _, err := io.ReadFull(d.rd, bKeyLen); err != nil {
return nil, fmt.Errorf("ncm read key length: %w", err)
}
iKeyLen := binary.LittleEndian.Uint32(bKeyLen)
bKeyRaw := make([]byte, iKeyLen)
if _, err := io.ReadFull(d.rd, bKeyRaw); err != nil {
return nil, fmt.Errorf("ncm read key data: %w", err)
}
for i := uint32(0); i < iKeyLen; i++ {
bKeyRaw[i] ^= 0x64
}
return crypto.PKCS7UnPadding(crypto.DecryptAES128ECB(bKeyRaw, keyCore))[17:], nil
}
func (d *decoder) skipMetaData() error {
bMetaLen := make([]byte, 4)
if _, err := io.ReadFull(d.rd, bMetaLen); err != nil {
return fmt.Errorf("ncm read meta length: %w", err)
}
iMetaLen := binary.LittleEndian.Uint32(bMetaLen)
if iMetaLen == 0 {
return nil
}
_, err := d.rd.Seek(int64(iMetaLen), io.SeekCurrent)
return err
}
func (d *decoder) skipCoverData() error {
bCoverFrameLen := make([]byte, 4)
if _, err := io.ReadFull(d.rd, bCoverFrameLen); err != nil {
return fmt.Errorf("ncm read cover frame length: %w", err)
}
coverFrameStartOffset, err := d.rd.Seek(0, io.SeekCurrent)
if err != nil {
return err
}
coverFrameLen := binary.LittleEndian.Uint32(bCoverFrameLen)
bCoverLen := make([]byte, 4)
if _, err := io.ReadFull(d.rd, bCoverLen); err != nil {
return fmt.Errorf("ncm read cover length: %w", err)
}
iCoverLen := binary.LittleEndian.Uint32(bCoverLen)
if _, err := io.ReadFull(d.rd, make([]byte, iCoverLen)); err != nil {
return fmt.Errorf("ncm skip cover data: %w", err)
}
offsetAudioData := coverFrameStartOffset + int64(coverFrameLen) + 4
_, err = d.rd.Seek(offsetAudioData, io.SeekStart)
return err
}
func (d *decoder) Read(buf []byte) (int, error) {
n, err := d.rd.Read(buf)
if n > 0 {
d.cipher.Decrypt(buf[:n], d.offset)
d.offset += n
}
return n, err
}
func init() {
decrypt.RegisterDecoder("ncm", false , newDecoder)
}
decrypt/ncm/ncm_cipher.go
+42
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@@ -0,0 +1,42 @@
package ncm
type ncmCipher struct {
key []byte
box []byte
}
func newNcmCipher(key []byte) *ncmCipher {
return &ncmCipher{
key: key,
box: buildKeyBox(key),
}
}
func (c *ncmCipher) Decrypt(buf []byte, offset int) {
for i := 0; i < len(buf); i++ {
buf[i] ^= c.box[(i+offset)&0xff]
}
}
func buildKeyBox(key []byte) []byte {
box := make([]byte, 256)
for i := 0; i < 256; i++ {
box[i] = byte(i)
}
var j byte
for i := 0; i < 256; i++ {
j = box[i] + j + key[i%len(key)]
box[i], box[j] = box[j], box[i]
}
ret := make([]byte, 256)
var _i byte
for i := 0; i < 256; i++ {
_i = byte(i + 1)
si := box[_i]
sj := box[_i+si]
ret[i] = box[si+sj]
}
return ret
}
decrypt/qmc/cipher_map.go
+39
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@@ -0,0 +1,39 @@
package qmc
import "errors"
type mapCipher struct {
key []byte
box []byte
size int
}
func newMapCipher(key []byte) (*mapCipher, error) {
if len(key) == 0 {
return nil, errors.New("qmc/cipher_map: invalid key size")
}
c := &mapCipher{key: key, size: len(key)}
c.box = make([]byte, c.size)
return c, nil
}
func (c *mapCipher) getMask(offset int) byte {
if offset > 0x7FFF {
offset %= 0x7FFF
}
idx := (offset*offset + 71214) % c.size
return c.rotate(c.key[idx], byte(idx)&0x7)
}
func (c *mapCipher) rotate(value byte, bits byte) byte {
rotate := (bits + 4) % 8
left := value << rotate
right := value >> rotate
return left | right
}
func (c *mapCipher) Decrypt(buf []byte, offset int) {
for i := 0; i < len(buf); i++ {
buf[i] ^= c.getMask(offset + i)
}
}
decrypt/qmc/cipher_map_test.go
+53
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@@ -0,0 +1,53 @@
package qmc
import (
"fmt"
"os"
"reflect"
"testing"
)
func loadTestDataMapCipher(name string) ([]byte, []byte, []byte, error) {
key, err := os.ReadFile(fmt.Sprintf("./testdata/%s_key.bin", name))
if err != nil {
return nil, nil, nil, err
}
raw, err := os.ReadFile(fmt.Sprintf("./testdata/%s_raw.bin", name))
if err != nil {
return nil, nil, nil, err
}
target, err := os.ReadFile(fmt.Sprintf("./testdata/%s_target.bin", name))
if err != nil {
return nil, nil, nil, err
}
return key, raw, target, nil
}
func Test_mapCipher_Decrypt(t *testing.T) {
tests := []struct {
name string
wantErr bool
}{
{"mflac_map", false},
{"mgg_map", false},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
key, raw, target, err := loadTestDataMapCipher(tt.name)
if err != nil {
t.Fatalf("load testing data failed: %s", err)
}
c, err := newMapCipher(key)
if err != nil {
t.Errorf("init mapCipher failed: %s", err)
return
}
c.Decrypt(raw, 0)
if !reflect.DeepEqual(raw, target) {
t.Error("overall")
}
})
}
}
decrypt/qmc/cipher_rc4.go
+124
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@@ -0,0 +1,124 @@
package qmc
import (
"errors"
)
// A rc4Cipher is an instance of RC4 using a particular key.
type rc4Cipher struct {
box []byte
key []byte
hash uint32
n int
}
// newRC4Cipher creates and returns a new rc4Cipher. The key argument should be the
// RC4 key, at least 1 byte and at most 256 bytes.
func newRC4Cipher(key []byte) (*rc4Cipher, error) {
n := len(key)
if n == 0 {
return nil, errors.New("qmc/cipher_rc4: invalid key size")
}
var c = rc4Cipher{key: key, n: n}
c.box = make([]byte, n)
for i := 0; i < n; i++ {
c.box[i] = byte(i)
}
var j = 0
for i := 0; i < n; i++ {
j = (j + int(c.box[i]) + int(key[i%n])) % n
c.box[i], c.box[j] = c.box[j], c.box[i]
}
c.getHashBase()
return &c, nil
}
func (c *rc4Cipher) getHashBase() {
c.hash = 1
for i := 0; i < c.n; i++ {
v := uint32(c.key[i])
if v == 0 {
continue
}
nextHash := c.hash * v
if nextHash == 0 || nextHash <= c.hash {
break
}
c.hash = nextHash
}
}
const (
rc4SegmentSize = 5120
rc4FirstSegmentSize = 128
)
func (c *rc4Cipher) Decrypt(src []byte, offset int) {
toProcess := len(src)
processed := 0
markProcess := func(p int) (finished bool) {
offset += p
toProcess -= p
processed += p
return toProcess == 0
}
if offset < rc4FirstSegmentSize {
blockSize := toProcess
if blockSize > rc4FirstSegmentSize-offset {
blockSize = rc4FirstSegmentSize - offset
}
c.encFirstSegment(src[:blockSize], offset)
if markProcess(blockSize) {
return
}
}
if offset%rc4SegmentSize != 0 {
blockSize := toProcess
if blockSize > rc4SegmentSize-offset%rc4SegmentSize {
blockSize = rc4SegmentSize - offset%rc4SegmentSize
}
c.encASegment(src[processed:processed+blockSize], offset)
if markProcess(blockSize) {
return
}
}
for toProcess > rc4SegmentSize {
c.encASegment(src[processed:processed+rc4SegmentSize], offset)
markProcess(rc4SegmentSize)
}
if toProcess > 0 {
c.encASegment(src[processed:], offset)
}
}
func (c *rc4Cipher) encFirstSegment(buf []byte, offset int) {
for i := 0; i < len(buf); i++ {
buf[i] ^= c.key[c.getSegmentSkip(offset+i)]
}
}
func (c *rc4Cipher) encASegment(buf []byte, offset int) {
box := make([]byte, c.n)
copy(box, c.box)
j, k := 0, 0
skipLen := (offset % rc4SegmentSize) + c.getSegmentSkip(offset/rc4SegmentSize)
for i := -skipLen; i < len(buf); i++ {
j = (j + 1) % c.n
k = (int(box[j]) + k) % c.n
box[j], box[k] = box[k], box[j]
if i >= 0 {
buf[i] ^= box[(int(box[j])+int(box[k]))%c.n]
}
}
}
func (c *rc4Cipher) getSegmentSkip(id int) int {
seed := int(c.key[id%c.n])
idx := int64(float64(c.hash) / float64((id+1)*seed) * 100.0)
return int(idx % int64(c.n))
}
decrypt/qmc/cipher_rc4_test.go
+115
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@@ -0,0 +1,115 @@
package qmc
import (
"os"
"reflect"
"testing"
)
func loadTestRC4CipherData(name string) ([]byte, []byte, []byte, error) {
prefix := "./testdata/" + name
key, err := os.ReadFile(prefix + "_key.bin")
if err != nil {
return nil, nil, nil, err
}
raw, err := os.ReadFile(prefix + "_raw.bin")
if err != nil {
return nil, nil, nil, err
}
target, err := os.ReadFile(prefix + "_target.bin")
if err != nil {
return nil, nil, nil, err
}
return key, raw, target, nil
}
func Test_rc4Cipher_Decrypt(t *testing.T) {
tests := []struct {
name string
wantErr bool
}{
{"mflac0_rc4", false},
{"mflac_rc4", false},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
key, raw, target, err := loadTestRC4CipherData(tt.name)
if err != nil {
t.Fatalf("load testing data failed: %s", err)
}
c, err := newRC4Cipher(key)
if err != nil {
t.Errorf("init rc4Cipher failed: %s", err)
return
}
c.Decrypt(raw, 0)
if !reflect.DeepEqual(raw, target) {
t.Error("overall")
}
})
}
}
func BenchmarkRc4Cipher_Decrypt(b *testing.B) {
key, raw, _, err := loadTestRC4CipherData("mflac0_rc4")
if err != nil {
b.Fatalf("load testing data failed: %s", err)
}
c, err := newRC4Cipher(key)
if err != nil {
b.Errorf("init rc4Cipher failed: %s", err)
return
}
b.ResetTimer()
for i := 0; i < b.N; i++ {
c.Decrypt(raw, 0)
}
}
func Test_rc4Cipher_encFirstSegment(t *testing.T) {
key, raw, target, err := loadTestRC4CipherData("mflac0_rc4")
if err != nil {
t.Fatalf("load testing data failed: %s", err)
}
t.Run("first-block(0~128)", func(t *testing.T) {
c, err := newRC4Cipher(key)
if err != nil {
t.Errorf("init rc4Cipher failed: %s", err)
return
}
c.Decrypt(raw[:128], 0)
if !reflect.DeepEqual(raw[:128], target[:128]) {
t.Error("first-block(0~128)")
}
})
}
func Test_rc4Cipher_encASegment(t *testing.T) {
key, raw, target, err := loadTestRC4CipherData("mflac0_rc4")
if err != nil {
t.Fatalf("load testing data failed: %s", err)
}
t.Run("align-block(128~5120)", func(t *testing.T) {
c, err := newRC4Cipher(key)
if err != nil {
t.Errorf("init rc4Cipher failed: %s", err)
return
}
c.Decrypt(raw[128:5120], 128)
if !reflect.DeepEqual(raw[128:5120], target[128:5120]) {
t.Error("align-block(128~5120)")
}
})
t.Run("simple-block(5120~10240)", func(t *testing.T) {
c, err := newRC4Cipher(key)
if err != nil {
t.Errorf("init rc4Cipher failed: %s", err)
return
}
c.Decrypt(raw[5120:10240], 5120)
if !reflect.DeepEqual(raw[5120:10240], target[5120:10240]) {
t.Error("align-block(128~5120)")
}
})
}
decrypt/qmc/cipher_static.go
+57
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@@ -0,0 +1,57 @@
package qmc
func newStaticCipher() *staticCipher {
return &defaultStaticCipher
}
var defaultStaticCipher = staticCipher{}
type staticCipher struct{}
func (c *staticCipher) Decrypt(buf []byte, offset int) {
for i := 0; i < len(buf); i++ {
buf[i] ^= c.getMask(offset + i)
}
}
func (c *staticCipher) getMask(offset int) byte {
if offset > 0x7FFF {
offset %= 0x7FFF
}
idx := (offset*offset + 27) & 0xff
return staticCipherBox[idx]
}
var staticCipherBox = [...]byte{
0x77, 0x48, 0x32, 0x73, 0xDE, 0xF2, 0xC0, 0xC8, //0x00
0x95, 0xEC, 0x30, 0xB2, 0x51, 0xC3, 0xE1, 0xA0, //0x08
0x9E, 0xE6, 0x9D, 0xCF, 0xFA, 0x7F, 0x14, 0xD1, //0x10
0xCE, 0xB8, 0xDC, 0xC3, 0x4A, 0x67, 0x93, 0xD6, //0x18
0x28, 0xC2, 0x91, 0x70, 0xCA, 0x8D, 0xA2, 0xA4, //0x20
0xF0, 0x08, 0x61, 0x90, 0x7E, 0x6F, 0xA2, 0xE0, //0x28
0xEB, 0xAE, 0x3E, 0xB6, 0x67, 0xC7, 0x92, 0xF4, //0x30
0x91, 0xB5, 0xF6, 0x6C, 0x5E, 0x84, 0x40, 0xF7, //0x38
0xF3, 0x1B, 0x02, 0x7F, 0xD5, 0xAB, 0x41, 0x89, //0x40
0x28, 0xF4, 0x25, 0xCC, 0x52, 0x11, 0xAD, 0x43, //0x48
0x68, 0xA6, 0x41, 0x8B, 0x84, 0xB5, 0xFF, 0x2C, //0x50
0x92, 0x4A, 0x26, 0xD8, 0x47, 0x6A, 0x7C, 0x95, //0x58
0x61, 0xCC, 0xE6, 0xCB, 0xBB, 0x3F, 0x47, 0x58, //0x60
0x89, 0x75, 0xC3, 0x75, 0xA1, 0xD9, 0xAF, 0xCC, //0x68
0x08, 0x73, 0x17, 0xDC, 0xAA, 0x9A, 0xA2, 0x16, //0x70
0x41, 0xD8, 0xA2, 0x06, 0xC6, 0x8B, 0xFC, 0x66, //0x78
0x34, 0x9F, 0xCF, 0x18, 0x23, 0xA0, 0x0A, 0x74, //0x80
0xE7, 0x2B, 0x27, 0x70, 0x92, 0xE9, 0xAF, 0x37, //0x88
0xE6, 0x8C, 0xA7, 0xBC, 0x62, 0x65, 0x9C, 0xC2, //0x90
0x08, 0xC9, 0x88, 0xB3, 0xF3, 0x43, 0xAC, 0x74, //0x98
0x2C, 0x0F, 0xD4, 0xAF, 0xA1, 0xC3, 0x01, 0x64, //0xA0
0x95, 0x4E, 0x48, 0x9F, 0xF4, 0x35, 0x78, 0x95, //0xA8
0x7A, 0x39, 0xD6, 0x6A, 0xA0, 0x6D, 0x40, 0xE8, //0xB0
0x4F, 0xA8, 0xEF, 0x11, 0x1D, 0xF3, 0x1B, 0x3F, //0xB8
0x3F, 0x07, 0xDD, 0x6F, 0x5B, 0x19, 0x30, 0x19, //0xC0
0xFB, 0xEF, 0x0E, 0x37, 0xF0, 0x0E, 0xCD, 0x16, //0xC8
0x49, 0xFE, 0x53, 0x47, 0x13, 0x1A, 0xBD, 0xA4, //0xD0
0xF1, 0x40, 0x19, 0x60, 0x0E, 0xED, 0x68, 0x09, //0xD8
0x06, 0x5F, 0x4D, 0xCF, 0x3D, 0x1A, 0xFE, 0x20, //0xE0
0x77, 0xE4, 0xD9, 0xDA, 0xF9, 0xA4, 0x2B, 0x76, //0xE8
0x1C, 0x71, 0xDB, 0x00, 0xBC, 0xFD, 0x0C, 0x6C, //0xF0
0xA5, 0x47, 0xF7, 0xF6, 0x00, 0x79, 0x4A, 0x11, //0xF8
}
decrypt/qmc/key_derive.go
+161
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@@ -0,0 +1,161 @@
package qmc
import (
"bytes"
"encoding/base64"
"errors"
"fmt"
"math"
"jsuse.com/dev/dec-music/internal/tea"
)
func simpleMakeKey(salt byte, length int) []byte {
keyBuf := make([]byte, length)
for i := 0; i < length; i++ {
tmp := math.Tan(float64(salt) + float64(i)*0.1)
keyBuf[i] = byte(math.Abs(tmp) * 100.0)
}
return keyBuf
}
const rawKeyPrefixV2 = "QQMusic EncV2,Key:"
func deriveKey(rawKey []byte) ([]byte, error) {
rawKeyDec := make([]byte, base64.StdEncoding.DecodedLen(len(rawKey)))
n, err := base64.StdEncoding.Decode(rawKeyDec, rawKey)
if err != nil {
return nil, err
}
rawKeyDec = rawKeyDec[:n]
if bytes.HasPrefix(rawKeyDec, []byte(rawKeyPrefixV2)) {
rawKeyDec, err = deriveKeyV2(bytes.TrimPrefix(rawKeyDec, []byte(rawKeyPrefixV2)))
if err != nil {
return nil, fmt.Errorf("deriveKeyV2 failed: %w", err)
}
}
return deriveKeyV1(rawKeyDec)
}
func deriveKeyV1(rawKeyDec []byte) ([]byte, error) {
if len(rawKeyDec) < 16 {
return nil, errors.New("key length is too short")
}
simpleKey := simpleMakeKey(106, 8)
teaKey := make([]byte, 16)
for i := 0; i < 8; i++ {
teaKey[i<<1] = simpleKey[i]
teaKey[i<<1+1] = rawKeyDec[i]
}
rs, err := decryptTencentTea(rawKeyDec[8:], teaKey)
if err != nil {
return nil, err
}
return append(rawKeyDec[:8], rs...), nil
}
var (
deriveV2Key1 = []byte{
0x33, 0x38, 0x36, 0x5A, 0x4A, 0x59, 0x21, 0x40,
0x23, 0x2A, 0x24, 0x25, 0x5E, 0x26, 0x29, 0x28,
}
deriveV2Key2 = []byte{
0x2A, 0x2A, 0x23, 0x21, 0x28, 0x23, 0x24, 0x25,
0x26, 0x5E, 0x61, 0x31, 0x63, 0x5A, 0x2C, 0x54,
}
)
func deriveKeyV2(raw []byte) ([]byte, error) {
buf, err := decryptTencentTea(raw, deriveV2Key1)
if err != nil {
return nil, err
}
buf, err = decryptTencentTea(buf, deriveV2Key2)
if err != nil {
return nil, err
}
n, err := base64.StdEncoding.Decode(buf, buf)
if err != nil {
return nil, err
}
return buf[:n], nil
}
func decryptTencentTea(inBuf []byte, key []byte) ([]byte, error) {
const saltLen = 2
const zeroLen = 7
if len(inBuf)%8 != 0 {
return nil, errors.New("inBuf size not a multiple of the block size")
}
if len(inBuf) < 16 {
return nil, errors.New("inBuf size too small")
}
blk, err := tea.NewCipherWithRounds(key, 32)
if err != nil {
return nil, err
}
destBuf := make([]byte, 8)
blk.Decrypt(destBuf, inBuf)
padLen := int(destBuf[0] & 0x7)
outLen := len(inBuf) - 1 - padLen - saltLen - zeroLen
out := make([]byte, outLen)
ivPrev := make([]byte, 8)
ivCur := inBuf[:8]
inBufPos := 8
destIdx := 1 + padLen
cryptBlock := func() {
ivPrev = ivCur
ivCur = inBuf[inBufPos : inBufPos+8]
xor8Bytes(destBuf, destBuf, inBuf[inBufPos:inBufPos+8])
blk.Decrypt(destBuf, destBuf)
inBufPos += 8
destIdx = 0
}
for i := 1; i <= saltLen; {
if destIdx < 8 {
destIdx++
i++
} else if destIdx == 8 {
cryptBlock()
}
}
outPos := 0
for outPos < outLen {
if destIdx < 8 {
out[outPos] = destBuf[destIdx] ^ ivPrev[destIdx]
destIdx++
outPos++
} else if destIdx == 8 {
cryptBlock()
}
}
for i := 1; i <= zeroLen; i++ {
if destBuf[destIdx] != ivPrev[destIdx] {
return nil, errors.New("zero check failed")
}
}
return out, nil
}
func xor8Bytes(dst, a, b []byte) {
for i := 0; i < 8; i++ {
dst[i] = a[i] ^ b[i]
}
}
decrypt/qmc/key_derive_test.go
+57
View File
@@ -0,0 +1,57 @@
package qmc
import (
"fmt"
"os"
"reflect"
"testing"
)
func TestSimpleMakeKey(t *testing.T) {
expect := []byte{0x69, 0x56, 0x46, 0x38, 0x2b, 0x20, 0x15, 0x0b}
t.Run("106,8", func(t *testing.T) {
if got := simpleMakeKey(106, 8); !reflect.DeepEqual(got, expect) {
t.Errorf("simpleMakeKey() = %v, want %v", got, expect)
}
})
}
func loadDecryptKeyData(name string) ([]byte, []byte, error) {
keyRaw, err := os.ReadFile(fmt.Sprintf("./testdata/%s_key_raw.bin", name))
if err != nil {
return nil, nil, err
}
keyDec, err := os.ReadFile(fmt.Sprintf("./testdata/%s_key.bin", name))
if err != nil {
return nil, nil, err
}
return keyRaw, keyDec, nil
}
func TestDecryptKey(t *testing.T) {
tests := []struct {
name string
filename string
wantErr bool
}{
{"mflac0_rc4(512)", "mflac0_rc4", false},
{"mflac_map(256)", "mflac_map", false},
{"mflac_rc4(256)", "mflac_rc4", false},
{"mgg_map(256)", "mgg_map", false},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
raw, want, err := loadDecryptKeyData(tt.filename)
if err != nil {
t.Fatalf("load test data failed: %s", err)
}
got, err := deriveKey(raw)
if (err != nil) != tt.wantErr {
t.Errorf("deriveKey() error = %v, wantErr %v", err, tt.wantErr)
return
}
if !reflect.DeepEqual(got, want) {
t.Errorf("deriveKey() got = %v..., want %v...",
string(got[:32]), string(want[:32]))
}
})
}
}
decrypt/qmc/key_mmkv.go
+158
View File
@@ -0,0 +1,158 @@
package qmc
import (
"errors"
"fmt"
"os"
"path/filepath"
"runtime"
"strings"
"unicode/utf8"
"jsuse.com/dev/dec-music/log"
"jsuse.com/dev/dec-music/mmkv"
)
var streamKeyVault mmkv.Vault
func readKeyFromMMKV(file string, logger *log.Logger) ([]byte, error) {
if file == "" {
return nil, errors.New("file path is required while reading key from mmkv")
}
if runtime.GOOS != "darwin" {
return nil, errors.New("mmkv vault not supported on this platform")
}
if streamKeyVault == nil {
mmkvDir, err := getRelativeMMKVDir(file)
if err != nil {
mmkvDir, err = getDefaultMMKVDir()
if err != nil {
return nil, fmt.Errorf("mmkv key vault not found: %w", err)
}
}
mgr, err := mmkv.NewManager(mmkvDir)
if err != nil {
return nil, fmt.Errorf("init mmkv manager: %w", err)
}
streamKeyVault, err = mgr.OpenVault("MMKVStreamEncryptId")
if err != nil {
return nil, fmt.Errorf("open mmkv vault: %w", err)
}
if logger != nil {
logger.Debug("mmkv vault opened, keys:", len(streamKeyVault.Keys()))
}
}
_, partName := filepath.Split(file)
partName = normalizeUnicode(partName)
buf, err := streamKeyVault.GetBytes(file)
if buf == nil {
filePaths := streamKeyVault.Keys()
fileNames := make([]string, len(filePaths))
for i, filePath := range filePaths {
_, name := filepath.Split(filePath)
fileNames[i] = normalizeUnicode(name)
}
for i, key := range fileNames {
if key != partName {
continue
}
buf, err = streamKeyVault.GetBytes(filePaths[i])
if err != nil && logger != nil {
logger.Warn("read key from mmkv", filePaths[i], err)
}
break
}
}
if len(buf) == 0 {
return nil, errors.New("key not found in mmkv vault")
}
return deriveKey(buf)
}
// OpenMMKVCLI opens a QQ Music MMKV vault (used by the CLI).
func OpenMMKVCLI(mmkvPath, key string, logger *log.Logger) error {
return openMMKV(mmkvPath, key, logger)
}
func openMMKV(mmkvPath, key string, logger *log.Logger) error {
filePath, fileName := filepath.Split(mmkvPath)
mgr, err := mmkv.NewManager(filepath.Dir(filePath))
if err != nil {
return fmt.Errorf("init mmkv manager: %w", err)
}
streamKeyVault, err = mgr.OpenVaultCrypto(fileName, key)
if err != nil {
return fmt.Errorf("open mmkv vault: %w", err)
}
if logger != nil {
logger.Debug("mmkv vault opened, keys:", len(streamKeyVault.Keys()))
}
return nil
}
func readKeyFromMMKVCustom(mid string) ([]byte, error) {
if streamKeyVault == nil {
return nil, fmt.Errorf("mmkv vault not loaded")
}
eKey, err := streamKeyVault.GetBytes(mid)
if err != nil {
return nil, fmt.Errorf("get eKey error: %w", err)
}
return deriveKey(eKey)
}
func getRelativeMMKVDir(file string) (string, error) {
mmkvDir := filepath.Join(filepath.Dir(file), "../mmkv")
if _, err := os.Stat(mmkvDir); err != nil {
return "", err
}
keyFile := filepath.Join(mmkvDir, "MMKVStreamEncryptId")
if _, err := os.Stat(keyFile); err != nil {
return "", err
}
return mmkvDir, nil
}
func getDefaultMMKVDir() (string, error) {
homeDir, err := os.UserHomeDir()
if err != nil {
return "", err
}
mmkvDir := filepath.Join(
homeDir,
"Library/Containers/com.tencent.QQMusicMac/Data",
"Library/Application Support/QQMusicMac/mmkv",
)
if _, err := os.Stat(mmkvDir); err != nil {
return "", err
}
keyFile := filepath.Join(mmkvDir, "MMKVStreamEncryptId")
if _, err := os.Stat(keyFile); err != nil {
return "", err
}
return mmkvDir, nil
}
// normalizeUnicode applies a simple NFC-like fix for macOS decomposed filenames.
func normalizeUnicode(str string) string {
if utf8.ValidString(str) && !strings.ContainsRune(str, '\u0300') {
return str
}
var b strings.Builder
for _, r := range str {
if r >= 0x0300 && r <= 0x036F {
continue
}
b.WriteRune(r)
}
return b.String()
}
decrypt/qmc/qmc.go
+198
View File
@@ -0,0 +1,198 @@
package qmc
import (
"bytes"
"encoding/binary"
"errors"
"fmt"
"io"
"runtime"
"strings"
"jsuse.com/dev/dec-music/decrypt"
"jsuse.com/dev/dec-music/internal/sniff"
"jsuse.com/dev/dec-music/log"
)
type decoder struct {
raw io.ReadSeeker
params *decrypt.DecoderParams
audio io.Reader
audioLen int
offset int
decodedKey []byte
cipher decrypt.StreamDecoder
logger *log.Logger
}
func newDecoder(p *decrypt.DecoderParams) decrypt.Decoder {
return &decoder{raw: p.Reader, params: p, logger: p.Logger}
}
func (d *decoder) Read(p []byte) (int, error) {
n, err := d.audio.Read(p)
if n > 0 {
d.cipher.Decrypt(p[:n], d.offset)
d.offset += n
}
return n, err
}
func (d *decoder) Validate() error {
if err := d.searchKey(); err != nil {
return err
}
var err error
if len(d.decodedKey) > 300 {
d.cipher, err = newRC4Cipher(d.decodedKey)
} else if len(d.decodedKey) != 0 {
d.cipher, err = newMapCipher(d.decodedKey)
} else {
d.cipher = newStaticCipher()
}
if err != nil {
return err
}
if err := d.validateDecode(); err != nil {
return err
}
if _, err := d.raw.Seek(0, io.SeekStart); err != nil {
return err
}
d.audio = io.LimitReader(d.raw, int64(d.audioLen))
return nil
}
func (d *decoder) validateDecode() error {
if _, err := d.raw.Seek(0, io.SeekStart); err != nil {
return fmt.Errorf("qmc seek to start: %w", err)
}
buf := make([]byte, 64)
if _, err := io.ReadFull(d.raw, buf); err != nil {
return fmt.Errorf("qmc read header: %w", err)
}
d.cipher.Decrypt(buf, 0)
if _, ok := sniff.AudioExtension(buf); !ok {
return errors.New("qmc: detect file type failed")
}
return nil
}
func (d *decoder) searchKey() (err error) {
fileSizeM4, err := d.raw.Seek(-4, io.SeekEnd)
if err != nil {
return err
}
fileSize := int(fileSizeM4) + 4
if runtime.GOOS == "darwin" && !strings.HasPrefix(d.params.Extension, ".qmc") {
d.decodedKey, err = readKeyFromMMKV(d.params.FilePath, d.logger)
if err == nil {
d.audioLen = fileSize
return nil
}
if d.logger != nil {
d.logger.Warn("read key from mmkv failed:", err)
}
}
suffixBuf := make([]byte, 4)
if _, err := io.ReadFull(d.raw, suffixBuf); err != nil {
return err
}
switch string(suffixBuf) {
case "QTag":
return d.readRawMetaQTag()
case "STag":
return errors.New("qmc: file with 'STag' suffix doesn't contains media key")
case "cex\x00":
footer, err := newMusicExTag(d.raw)
if err != nil {
return err
}
d.audioLen = fileSize - int(footer.tagSize)
d.decodedKey, err = readKeyFromMMKVCustom(footer.mediaFileName)
return err
default:
size := binary.LittleEndian.Uint32(suffixBuf)
if size <= 0xFFFF && size != 0 {
return d.readRawKey(int64(size))
}
d.audioLen = fileSize
return nil
}
}
func (d *decoder) readRawKey(rawKeyLen int64) error {
audioLen, err := d.raw.Seek(-(4 + rawKeyLen), io.SeekEnd)
if err != nil {
return err
}
d.audioLen = int(audioLen)
rawKeyData, err := io.ReadAll(io.LimitReader(d.raw, rawKeyLen))
if err != nil {
return err
}
rawKeyData = bytes.TrimRight(rawKeyData, "\x00")
d.decodedKey, err = deriveKey(rawKeyData)
return err
}
func (d *decoder) readRawMetaQTag() error {
if _, err := d.raw.Seek(-8, io.SeekEnd); err != nil {
return err
}
buf, err := io.ReadAll(io.LimitReader(d.raw, 4))
if err != nil {
return err
}
rawMetaLen := int64(binary.BigEndian.Uint32(buf))
audioLen, err := d.raw.Seek(-(8 + rawMetaLen), io.SeekEnd)
if err != nil {
return err
}
d.audioLen = int(audioLen)
rawMetaData, err := io.ReadAll(io.LimitReader(d.raw, rawMetaLen))
if err != nil {
return err
}
items := strings.Split(string(rawMetaData), ",")
if len(items) != 3 {
return errors.New("invalid raw meta data")
}
d.decodedKey, err = deriveKey([]byte(items[0]))
return err
}
func init() {
supportedExts := []string{
"qmc0", "qmc3", "qmc2", "qmc4", "qmc6", "qmc8",
"qmcflac", "qmcogg", "tkm",
"bkcmp3", "bkcm4a", "bkcflac", "bkcwav", "bkcape", "bkcogg", "bkcwma",
"666c6163", "6d7033", "6f6767", "6d3461", "776176", "mmp4",
}
for _, ext := range supportedExts {
decrypt.RegisterDecoder(ext, false , newDecoder)
}
for _, ext := range []string{"mgg", "mflac"} {
decrypt.RegisterDecoder(ext, false , newDecoder)
for _, suffix := range []string{"0", "1", "a", "h", "l"} {
decrypt.RegisterDecoder(ext+suffix, false , newDecoder)
}
}
}
decrypt/qmc/qmc_footer_musicex.go
+90
View File
@@ -0,0 +1,90 @@
package qmc
import (
bytes "bytes"
"encoding/binary"
"errors"
"fmt"
"io"
"strings"
)
type musicExTagV1 struct {
songID uint32
unknown1 uint32
unknown2 uint32
mediaID string
mediaFileName string
unknown3 uint32
tagSize uint32
tagVersion uint32
tagMagic []byte
}
func newMusicExTag(f io.ReadSeeker) (*musicExTagV1, error) {
_, err := f.Seek(-16, io.SeekEnd)
if err != nil {
return nil, fmt.Errorf("musicex seek error: %w", err)
}
buffer := make([]byte, 16)
bytesRead, err := f.Read(buffer)
if err != nil {
return nil, fmt.Errorf("get musicex error: %w", err)
}
if bytesRead != 16 {
return nil, fmt.Errorf("MusicExV1: read %d bytes (expected %d)", bytesRead, 16)
}
tag := &musicExTagV1{
tagSize: binary.LittleEndian.Uint32(buffer[0x00:0x04]),
tagVersion: binary.LittleEndian.Uint32(buffer[0x04:0x08]),
tagMagic: buffer[0x08:0x10],
}
if !bytes.Equal(tag.tagMagic, []byte("musicex\x00")) {
return nil, errors.New("MusicEx magic mismatch")
}
if tag.tagVersion != 1 {
return nil, fmt.Errorf("unsupported musicex tag version: %d", tag.tagVersion)
}
if tag.tagSize < 0xC0 {
return nil, fmt.Errorf("unsupported musicex tag size: 0x%x", tag.tagSize)
}
buffer = make([]byte, tag.tagSize)
bytesRead, err = f.Read(buffer)
if err != nil {
return nil, err
}
if uint32(bytesRead) != tag.tagSize {
return nil, fmt.Errorf("MusicExV1: read %d bytes (expected %d)", bytesRead, tag.tagSize)
}
tag.songID = binary.LittleEndian.Uint32(buffer[0x00:0x04])
tag.unknown1 = binary.LittleEndian.Uint32(buffer[0x04:0x08])
tag.unknown2 = binary.LittleEndian.Uint32(buffer[0x08:0x0C])
tag.mediaID = readUnicodeTagName(buffer[0x0C:], 30*2)
tag.mediaFileName = readUnicodeTagName(buffer[0x48:], 50*2)
tag.unknown3 = binary.LittleEndian.Uint32(buffer[0xAC:0xB0])
return tag, nil
}
// readUnicodeTagName reads a buffer to maxLen.
// reconstruct text by skipping alternate char (ascii chars encoded in UTF-16-LE),
// until finding a zero or reaching maxLen.
func readUnicodeTagName(buffer []byte, maxLen int) string {
builder := strings.Builder{}
for i := 0; i < maxLen; i += 2 {
chr := buffer[i]
if chr != 0 {
builder.WriteByte(chr)
} else {
break
}
}
return builder.String()
}
decrypt/qmc/qmc_test.go
+101
View File
@@ -0,0 +1,101 @@
package qmc
import (
"bytes"
"fmt"
"io"
"os"
"reflect"
"testing"
"jsuse.com/dev/dec-music/decrypt"
)
func loadTestDataQmcDecoder(filename string) ([]byte, []byte, error) {
encBody, err := os.ReadFile(fmt.Sprintf("./testdata/%s_raw.bin", filename))
if err != nil {
return nil, nil, err
}
encSuffix, err := os.ReadFile(fmt.Sprintf("./testdata/%s_suffix.bin", filename))
if err != nil {
return nil, nil, err
}
target, err := os.ReadFile(fmt.Sprintf("./testdata/%s_target.bin", filename))
if err != nil {
return nil, nil, err
}
return bytes.Join([][]byte{encBody, encSuffix}, nil), target, nil
}
func TestMflac0Decoder_Read(t *testing.T) {
tests := []struct {
name string
fileExt string
wantErr bool
}{
{"mflac0_rc4", ".mflac0", false},
{"mflac_rc4", ".mflac", false},
{"mflac_map", ".mflac", false},
{"mgg_map", ".mgg", false},
{"qmc0_static", ".qmc0", false},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
raw, target, err := loadTestDataQmcDecoder(tt.name)
if err != nil {
t.Fatal(err)
}
d := newDecoder(&decrypt.DecoderParams{
Reader: bytes.NewReader(raw),
Extension: tt.fileExt,
})
if err := d.Validate(); err != nil {
t.Errorf("validate file error = %v", err)
}
buf := make([]byte, len(target))
if _, err := io.ReadFull(d, buf); err != nil {
t.Errorf("read bytes from decoder error = %v", err)
return
}
if !reflect.DeepEqual(buf, target) {
t.Errorf("Decrypt() got = %v, want %v", buf[:32], target[:32])
}
})
}
}
func TestMflac0Decoder_Validate(t *testing.T) {
tests := []struct {
name string
fileExt string
wantErr bool
}{
{"mflac0_rc4", ".flac", false},
{"mflac_map", ".flac", false},
{"mgg_map", ".ogg", false},
{"qmc0_static", ".mp3", false},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
raw, _, err := loadTestDataQmcDecoder(tt.name)
if err != nil {
t.Fatal(err)
}
d := newDecoder(&decrypt.DecoderParams{
Reader: bytes.NewReader(raw),
Extension: tt.fileExt,
})
if err := d.Validate(); err != nil {
t.Errorf("read bytes from decoder error = %v", err)
return
}
})
}
}
decrypt/raw.go
+50
View File
@@ -0,0 +1,50 @@
package decrypt
import (
"errors"
"fmt"
"io"
"jsuse.com/dev/dec-music/internal/sniff"
)
type rawDecoder struct {
rd io.ReadSeeker
audioExt string
}
func newRawDecoder(p *DecoderParams) Decoder {
return &rawDecoder{rd: p.Reader}
}
func (d *rawDecoder) Validate() error {
header := make([]byte, 16)
if _, err := io.ReadFull(d.rd, header); err != nil {
return fmt.Errorf("read file header failed: %v", err)
}
if _, err := d.rd.Seek(0, io.SeekStart); err != nil {
return fmt.Errorf("seek file failed: %v", err)
}
var ok bool
d.audioExt, ok = sniff.AudioExtension(header)
if !ok {
return errors.New("raw: sniff audio type failed")
}
return nil
}
func (d *rawDecoder) Read(p []byte) (n int, err error) {
return d.rd.Read(p)
}
func init() {
RegisterDecoder("mp3", true, newRawDecoder)
RegisterDecoder("flac", true, newRawDecoder)
RegisterDecoder("ogg", true, newRawDecoder)
RegisterDecoder("m4a", true, newRawDecoder)
RegisterDecoder("wav", true, newRawDecoder)
RegisterDecoder("wma", true, newRawDecoder)
RegisterDecoder("aac", true, newRawDecoder)
}
decrypt/tm/tm.go
+56
View File
@@ -0,0 +1,56 @@
package tm
import (
"bytes"
"errors"
"fmt"
"io"
"jsuse.com/dev/dec-music/decrypt"
"jsuse.com/dev/dec-music/internal/sniff"
)
var replaceHeader = []byte{0x00, 0x00, 0x00, 0x20, 0x66, 0x74, 0x79, 0x70}
var magicHeader = []byte{0x51, 0x51, 0x4D, 0x55} //0x15, 0x1D, 0x1A, 0x21
type decoder struct {
raw io.ReadSeeker // raw is the original file reader
offset int
audio io.Reader // audio is the decrypted audio data
}
func (d *decoder) Validate() error {
header := make([]byte, 8)
if _, err := io.ReadFull(d.raw, header); err != nil {
return fmt.Errorf("tm read header: %w", err)
}
if bytes.Equal(magicHeader, header[:len(magicHeader)]) { // replace m4a header
d.audio = io.MultiReader(bytes.NewReader(replaceHeader), d.raw)
return nil
}
if _, ok := sniff.AudioExtension(header); ok { // not encrypted
d.audio = io.MultiReader(bytes.NewReader(header), d.raw)
return nil
}
return errors.New("tm: valid magic header")
}
func (d *decoder) Read(buf []byte) (int, error) {
return d.audio.Read(buf)
}
func newTmDecoder(p *decrypt.DecoderParams) decrypt.Decoder {
return &decoder{raw: p.Reader}
}
func init() {
// QQ Music IOS M4a (replace header)
decrypt.RegisterDecoder("tm2", false, newTmDecoder)
decrypt.RegisterDecoder("tm6", false, newTmDecoder)
decrypt.RegisterDecoder("tm0", false, newTmDecoder)
decrypt.RegisterDecoder("tm3", false, newTmDecoder)
}
decrypt/xiami/xm.go
+91
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@@ -0,0 +1,91 @@
package xiami
import (
"bytes"
"errors"
"fmt"
"io"
"jsuse.com/dev/dec-music/decrypt"
)
var (
magicHeader = []byte{'i', 'f', 'm', 't'}
magicHeader2 = []byte{0xfe, 0xfe, 0xfe, 0xfe}
typeMapping = map[string]string{
" WAV": "wav",
"FLAC": "flac",
" MP3": "mp3",
" A4M": "m4a",
}
ErrMagicHeader = errors.New("xm magic header not matched")
)
type decoder struct {
rd io.ReadSeeker // rd is the original file reader
offset int
cipher decrypt.StreamDecoder
outputExt string
}
func (d *decoder) GetAudioExt() string {
if d.outputExt != "" {
return "." + d.outputExt
}
return ""
}
func newDecoder(p *decrypt.DecoderParams) decrypt.Decoder {
return &decoder{rd: p.Reader}
}
// Validate checks if the file is a valid xiami .xm file.
// rd will set to the beginning of the encrypted audio data.
func (d *decoder) Validate() error {
header := make([]byte, 16) // xm header is fixed to 16 bytes
if _, err := io.ReadFull(d.rd, header); err != nil {
return fmt.Errorf("xm read header: %w", err)
}
// 0x00 - 0x03 and 0x08 - 0x0B: magic header
if !bytes.Equal(magicHeader, header[:4]) || !bytes.Equal(magicHeader2, header[8:12]) {
return ErrMagicHeader
}
// 0x04 - 0x07: Audio File Type
var ok bool
d.outputExt, ok = typeMapping[string(header[4:8])]
if !ok {
return fmt.Errorf("xm detect unknown audio type: %s", string(header[4:8]))
}
// 0x0C - 0x0E, Encrypt Start At, LittleEndian Unit24
encStartAt := uint32(header[12]) | uint32(header[13])<<8 | uint32(header[14])<<16
// 0x0F, XOR Mask
d.cipher = newXmCipher(header[15], int(encStartAt))
return nil
}
func (d *decoder) Read(p []byte) (int, error) {
n, err := d.rd.Read(p)
if n > 0 {
d.cipher.Decrypt(p[:n], d.offset)
d.offset += n
}
return n, err
}
func init() {
// Xiami Wav/M4a/Mp3/Flac
decrypt.RegisterDecoder("xm", false , newDecoder)
// Xiami Typed Format
decrypt.RegisterDecoder("wav", false , newDecoder)
decrypt.RegisterDecoder("mp3", false , newDecoder)
decrypt.RegisterDecoder("flac", false , newDecoder)
decrypt.RegisterDecoder("m4a", false , newDecoder)
}
decrypt/xiami/xm_cipher.go
+21
View File
@@ -0,0 +1,21 @@
package xiami
type xmCipher struct {
mask byte
encryptStartAt int
}
func newXmCipher(mask byte, encryptStartAt int) *xmCipher {
return &xmCipher{
mask: mask,
encryptStartAt: encryptStartAt,
}
}
func (c *xmCipher) Decrypt(buf []byte, offset int) {
for i := 0; i < len(buf); i++ {
if offset+i >= c.encryptStartAt {
buf[i] ^= c.mask
}
}
}
decrypt/ximalaya/x2m_crypto.go
+34
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@@ -0,0 +1,34 @@
package ximalaya
import (
_ "embed"
"encoding/binary"
)
const x2mHeaderSize = 1024
var x2mKey = [...]byte{'x', 'm', 'l', 'y'}
var x2mScrambleTable = [x2mHeaderSize]uint16{}
//go:embed x2m_scramble_table.bin
var x2mScrambleTableBytes []byte
func init() {
if len(x2mScrambleTableBytes) != 2*x2mHeaderSize {
panic("invalid x2m scramble table")
}
for i := range x2mScrambleTable {
x2mScrambleTable[i] = binary.LittleEndian.Uint16(x2mScrambleTableBytes[i*2:])
}
}
// decryptX2MHeader decrypts the header of ximalaya .x2m file.
// make sure input src is 1024(x2mHeaderSize) bytes long.
func decryptX2MHeader(src []byte) []byte {
dst := make([]byte, len(src))
for dstIdx := range src {
srcIdx := x2mScrambleTable[dstIdx]
dst[dstIdx] = src[srcIdx] ^ x2mKey[dstIdx%len(x2mKey)]
}
return dst
}
decrypt/ximalaya/x2m_scramble_table.bin
BIN
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Binary file not shown.
decrypt/ximalaya/x3m_crypto.go
+40
View File
@@ -0,0 +1,40 @@
package ximalaya
import (
_ "embed"
"encoding/binary"
)
var x3mKey = [...]byte{
'3', '9', '8', '9', 'd', '1', '1', '1',
'a', 'a', 'd', '5', '6', '1', '3', '9',
'4', '0', 'f', '4', 'f', 'c', '4', '4',
'b', '6', '3', '9', 'b', '2', '9', '2',
}
const x3mHeaderSize = 1024
var x3mScrambleTable = [x3mHeaderSize]uint16{}
//go:embed x3m_scramble_table.bin
var x3mScrambleTableBytes []byte
func init() {
if len(x3mScrambleTableBytes) != 2*x3mHeaderSize {
panic("invalid x3m scramble table")
}
for i := range x3mScrambleTable {
x3mScrambleTable[i] = binary.LittleEndian.Uint16(x3mScrambleTableBytes[i*2:])
}
}
// decryptX3MHeader decrypts the header of ximalaya .x3m file.
// make sure input src is 1024 (x3mHeaderSize) bytes long.
func decryptX3MHeader(src []byte) []byte {
dst := make([]byte, len(src))
for dstIdx := range src {
srcIdx := x3mScrambleTable[dstIdx]
dst[dstIdx] = src[srcIdx] ^ x3mKey[dstIdx%len(x3mKey)]
}
return dst
}
decrypt/ximalaya/x3m_scramble_table.bin
BIN
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Binary file not shown.
decrypt/ximalaya/ximalaya.go
+57
View File
@@ -0,0 +1,57 @@
package ximalaya
import (
"bytes"
"fmt"
"io"
"jsuse.com/dev/dec-music/decrypt"
"jsuse.com/dev/dec-music/internal/sniff"
)
type decoder struct {
rd io.ReadSeeker
offset int
audio io.Reader
}
func newDecoder(p *decrypt.DecoderParams) decrypt.Decoder {
return &decoder{rd: p.Reader}
}
func (d *decoder) Validate() error {
encryptedHeader := make([]byte, x2mHeaderSize)
if _, err := io.ReadFull(d.rd, encryptedHeader); err != nil {
return fmt.Errorf("ximalaya read header: %w", err)
}
{ // try to decode with x2m
header := decryptX2MHeader(encryptedHeader)
if _, ok := sniff.AudioExtension(header); ok {
d.audio = io.MultiReader(bytes.NewReader(header), d.rd)
return nil
}
}
{ // try to decode with x3m
// not read file again, since x2m and x3m have the same header size
header := decryptX3MHeader(encryptedHeader)
if _, ok := sniff.AudioExtension(header); ok {
d.audio = io.MultiReader(bytes.NewReader(header), d.rd)
return nil
}
}
return fmt.Errorf("ximalaya: unknown format")
}
func (d *decoder) Read(p []byte) (n int, err error) {
return d.audio.Read(p)
}
func init() {
decrypt.RegisterDecoder("x2m", false , newDecoder)
decrypt.RegisterDecoder("x3m", false , newDecoder)
decrypt.RegisterDecoder("xm", false , newDecoder)
}
go.mod
+11
View File
@@ -0,0 +1,11 @@
module jsuse.com/dev/dec-music
go 1.24.0
require github.com/urfave/cli/v2 v2.27.7
require (
github.com/cpuguy83/go-md2man/v2 v2.0.7 // indirect
github.com/russross/blackfriday/v2 v2.1.0 // indirect
github.com/xrash/smetrics v0.0.0-20250705151800-55b8f293f342 // indirect
)
go.sum
+65
View File
@@ -0,0 +1,65 @@
github.com/cpuguy83/go-md2man/v2 v2.0.7 h1:zbFlGlXEAKlwXpmvle3d8Oe3YnkKIK4xSRTd3sHPnBo=
github.com/cpuguy83/go-md2man/v2 v2.0.7/go.mod h1:oOW0eioCTA6cOiMLiUPZOpcVxMig6NIQQ7OS05n1F4g=
github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/fsnotify/fsnotify v1.9.0 h1:2Ml+OJNzbYCTzsxtv8vKSFD9PbJjmhYF14k/jKC7S9k=
github.com/fsnotify/fsnotify v1.9.0/go.mod h1:8jBTzvmWwFyi3Pb8djgCCO5IBqzKJ/Jwo8TRcHyHii0=
github.com/go-flac/flacpicture v0.3.0 h1:LkmTxzFLIynwfhHiZsX0s8xcr3/u33MzvV89u+zOT8I=
github.com/go-flac/flacpicture v0.3.0/go.mod h1:DPbrzVYQ3fJcvSgLFp9HXIrEQEdfdk/+m0nQCzwodZI=
github.com/go-flac/flacvorbis v0.2.0 h1:KH0xjpkNTXFER4cszH4zeJxYcrHbUobz/RticWGOESs=
github.com/go-flac/flacvorbis v0.2.0/go.mod h1:uIysHOtuU7OLGoCRG92bvnkg7QEqHx19qKRV6K1pBrI=
github.com/go-flac/go-flac v1.0.0 h1:6qI9XOVLcO50xpzm3nXvO31BgDgHhnr/p/rER/K/doY=
github.com/go-flac/go-flac v1.0.0/go.mod h1:WnZhcpmq4u1UdZMNn9LYSoASpWOCMOoxXxcWEHSzkW8=
github.com/gookit/assert v0.1.1 h1:lh3GcawXe/p+cU7ESTZ5Ui3Sm/x8JWpIis4/1aF0mY0=
github.com/gookit/assert v0.1.1/go.mod h1:jS5bmIVQZTIwk42uXl4lyj4iaaxx32tqH16CFj0VX2E=
github.com/gookit/color v1.6.0 h1:JjJXBTk1ETNyqyilJhkTXJYYigHG24TM9Xa2M1xAhRA=
github.com/gookit/color v1.6.0/go.mod h1:9ACFc7/1IpHGBW8RwuDm/0YEnhg3dwwXpoMsmtyHfjs=
github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e/go.mod h1:pJLUxLENpZxwdsKMEsNbx1VGcRFpLqf3715MtcvvzbA=
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/rogpeppe/go-internal v1.9.0/go.mod h1:WtVeX8xhTBvf0smdhujwtBcq4Qrzq/fJaraNFVN+nFs=
github.com/rogpeppe/go-internal v1.14.1 h1:UQB4HGPB6osV0SQTLymcB4TgvyWu6ZyliaW0tI/otEQ=
github.com/rogpeppe/go-internal v1.14.1/go.mod h1:MaRKkUm5W0goXpeCfT7UZI6fk/L7L7so1lCWt35ZSgc=
github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf35Ld67mk=
github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
github.com/samber/lo v1.52.0 h1:Rvi+3BFHES3A8meP33VPAxiBZX/Aws5RxrschYGjomw=
github.com/samber/lo v1.52.0/go.mod h1:4+MXEGsJzbKGaUEQFKBq2xtfuznW9oz/WrgyzMzRoM0=
github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
github.com/urfave/cli/v2 v2.27.7 h1:bH59vdhbjLv3LAvIu6gd0usJHgoTTPhCFib8qqOwXYU=
github.com/urfave/cli/v2 v2.27.7/go.mod h1:CyNAG/xg+iAOg0N4MPGZqVmv2rCoP267496AOXUZjA4=
github.com/xo/terminfo v0.0.0-20220910002029-abceb7e1c41e h1:JVG44RsyaB9T2KIHavMF/ppJZNG9ZpyihvCd0w101no=
github.com/xo/terminfo v0.0.0-20220910002029-abceb7e1c41e/go.mod h1:RbqR21r5mrJuqunuUZ/Dhy/avygyECGrLceyNeo4LiM=
github.com/xrash/smetrics v0.0.0-20240521201337-686a1a2994c1 h1:gEOO8jv9F4OT7lGCjxCBTO/36wtF6j2nSip77qHd4x4=
github.com/xrash/smetrics v0.0.0-20240521201337-686a1a2994c1/go.mod h1:Ohn+xnUBiLI6FVj/9LpzZWtj1/D6lUovWYBkxHVV3aM=
github.com/xrash/smetrics v0.0.0-20250705151800-55b8f293f342 h1:FnBeRrxr7OU4VvAzt5X7s6266i6cSVkkFPS0TuXWbIg=
github.com/xrash/smetrics v0.0.0-20250705151800-55b8f293f342/go.mod h1:Ohn+xnUBiLI6FVj/9LpzZWtj1/D6lUovWYBkxHVV3aM=
go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=
go.uber.org/goleak v1.3.0/go.mod h1:CoHD4mav9JJNrW/WLlf7HGZPjdw8EucARQHekz1X6bE=
go.uber.org/multierr v1.11.0 h1:blXXJkSxSSfBVBlC76pxqeO+LN3aDfLQo+309xJstO0=
go.uber.org/multierr v1.11.0/go.mod h1:20+QtiLqy0Nd6FdQB9TLXag12DsQkrbs3htMFfDN80Y=
go.uber.org/zap v1.27.1 h1:08RqriUEv8+ArZRYSTXy1LeBScaMpVSTBhCeaZYfMYc=
go.uber.org/zap v1.27.1/go.mod h1:GB2qFLM7cTU87MWRP2mPIjqfIDnGu+VIO4V/SdhGo2E=
golang.org/x/crypto v0.47.0 h1:V6e3FRj+n4dbpw86FJ8Fv7XVOql7TEwpHapKoMJ/GO8=
golang.org/x/crypto v0.47.0/go.mod h1:ff3Y9VzzKbwSSEzWqJsJVBnWmRwRSHt/6Op5n9bQc4A=
golang.org/x/exp v0.0.0-20260112195511-716be5621a96 h1:Z/6YuSHTLOHfNFdb8zVZomZr7cqNgTJvA8+Qz75D8gU=
golang.org/x/exp v0.0.0-20260112195511-716be5621a96/go.mod h1:nzimsREAkjBCIEFtHiYkrJyT+2uy9YZJB7H1k68CXZU=
golang.org/x/sys v0.40.0 h1:DBZZqJ2Rkml6QMQsZywtnjnnGvHza6BTfYFWY9kjEWQ=
golang.org/x/sys v0.40.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
golang.org/x/text v0.33.0 h1:B3njUFyqtHDUI5jMn1YIr5B0IE2U0qck04r6d4KPAxE=
golang.org/x/text v0.33.0/go.mod h1:LuMebE6+rBincTi9+xWTY8TztLzKHc/9C1uBCG27+q8=
google.golang.org/protobuf v1.36.11 h1:fV6ZwhNocDyBLK0dj+fg8ektcVegBBuEolpbTQyBNVE=
google.golang.org/protobuf v1.36.11/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=
gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
internal/crypto/crypto.go
+33
View File
@@ -0,0 +1,33 @@
package crypto
import "crypto/aes"
// PKCS7UnPadding removes PKCS#7 padding.
func PKCS7UnPadding(encrypt []byte) []byte {
length := len(encrypt)
if length == 0 {
return encrypt
}
unPadding := int(encrypt[length-1])
if unPadding <= 0 || unPadding > length {
return encrypt
}
return encrypt[:length-unPadding]
}
// DecryptAES128ECB decrypts data with AES-128 ECB (block size 16).
func DecryptAES128ECB(data, key []byte) []byte {
cipher, err := aes.NewCipher(key)
if err != nil {
return nil
}
decrypted := make([]byte, len(data))
size := aes.BlockSize
for bs, be := 0, size; bs < len(data); bs, be = bs+size, be+size {
if be > len(data) {
break
}
cipher.Decrypt(decrypted[bs:be], data[bs:be])
}
return decrypted
}
internal/fileutil/fileutil.go
+50
View File
@@ -0,0 +1,50 @@
package fileutil
import (
"os"
"path/filepath"
"strings"
)
var (
standardMediaExts = map[string]struct{}{
".mp3": {}, ".flac": {}, ".wav": {}, ".m4a": {},
".ogg": {}, ".opus": {}, ".aac": {}, ".wma": {},
".ape": {}, ".alac": {}, ".dsf": {}, ".dff": {},
}
encryptedMediaExts = map[string]struct{}{
".kgma": {}, ".kgm": {},
".ncm": {},
".qmc": {}, ".qmc0": {}, ".qmc3": {}, ".qmcflac": {}, ".qmcogg": {},
".mgg": {}, ".mflac": {},
".tm": {}, ".tkm": {},
".xiami": {}, ".xm": {},
".ximalaya": {}, ".xmly": {},
".x2m": {}, ".x3m": {},
".kwm": {},
}
videoMediaExts = map[string]struct{}{
".mp4": {}, ".mkv": {}, ".avi": {}, ".mov": {}, ".flv": {},
}
)
// IsMediaFile reports whether the file name looks like a media file this tool handles.
func IsMediaFile(fileName string) bool {
ext := strings.ToLower(filepath.Ext(fileName))
if _, ok := standardMediaExts[ext]; ok {
return true
}
if _, ok := encryptedMediaExts[ext]; ok {
return true
}
if _, ok := videoMediaExts[ext]; ok {
return true
}
return false
}
// FileExist reports whether path exists.
func FileExist(path string) bool {
_, err := os.Stat(path)
return err == nil
}
internal/sniff/audio.go
+105
View File
@@ -0,0 +1,105 @@
package sniff
import (
"bytes"
"encoding/binary"
"slices"
)
type Sniffer interface {
Sniff(header []byte) bool
}
var audioExtensions = map[string]Sniffer{
// ref: https://mimesniff.spec.whatwg.org
".mp3": prefixSniffer("ID3"), // todo: check mp3 without ID3v2 tag
".ogg": prefixSniffer("OggS"),
".wav": prefixSniffer("RIFF"),
// ref: https://www.loc.gov/preservation/digital/formats/fdd/fdd000027.shtml
".wma": prefixSniffer{
0x30, 0x26, 0xb2, 0x75, 0x8e, 0x66, 0xcf, 0x11,
0xa6, 0xd9, 0x00, 0xaa, 0x00, 0x62, 0xce, 0x6c,
},
// ref: https://www.garykessler.net/library/file_sigs.html
".m4a": m4aSniffer{}, // MPEG-4 container, Apple Lossless Audio Codec
".mp4": &mpeg4Sniffer{}, // MPEG-4 container, other fallback
".flac": prefixSniffer("fLaC"), // ref: https://xiph.org/flac/format.html
".dff": prefixSniffer("FRM8"), // DSDIFF, ref: https://www.sonicstudio.com/pdf/dsd/DSDIFF_1.5_Spec.pdf
}
// AudioExtension sniffs the known audio types, and returns the file extension.
// header is recommended to at least 16 bytes.
func AudioExtension(header []byte) (string, bool) {
for ext, sniffer := range audioExtensions {
if sniffer.Sniff(header) {
return ext, true
}
}
return "", false
}
// AudioExtensionWithFallback is equivalent to AudioExtension, but returns fallback
// most likely to use .mp3 as fallback, because mp3 files may not have ID3v2 tag.
func AudioExtensionWithFallback(header []byte, fallback string) string {
ext, ok := AudioExtension(header)
if !ok {
return fallback
}
return ext
}
type prefixSniffer []byte
func (s prefixSniffer) Sniff(header []byte) bool {
return bytes.HasPrefix(header, s)
}
type m4aSniffer struct{}
func (m4aSniffer) Sniff(header []byte) bool {
box := readMpeg4FtypBox(header)
if box == nil {
return false
}
return box.majorBrand == "M4A " || slices.Contains(box.compatibleBrands, "M4A ")
}
type mpeg4Sniffer struct{}
func (s *mpeg4Sniffer) Sniff(header []byte) bool {
return readMpeg4FtypBox(header) != nil
}
type mpeg4FtpyBox struct {
majorBrand string
minorVersion uint32
compatibleBrands []string
}
func readMpeg4FtypBox(header []byte) *mpeg4FtpyBox {
if (len(header) < 8) || !bytes.Equal([]byte("ftyp"), header[4:8]) {
return nil // not a valid ftyp box
}
size := binary.BigEndian.Uint32(header[0:4]) // size
if size < 16 || size%4 != 0 {
return nil // invalid ftyp box
}
box := mpeg4FtpyBox{
majorBrand: string(header[8:12]),
minorVersion: binary.BigEndian.Uint32(header[12:16]),
}
// compatible brands
for i := 16; i < int(size) && i+4 < len(header); i += 4 {
box.compatibleBrands = append(box.compatibleBrands, string(header[i:i+4]))
}
return &box
}
internal/tea/cipher.go
+116
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@@ -0,0 +1,116 @@
// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package tea implements the TEA algorithm, as defined in Needham and
// Wheeler's 1994 technical report, “TEA, a Tiny Encryption Algorithm”. See
// http://www.cix.co.uk/~klockstone/tea.pdf for details.
//
// TEA is a legacy cipher and its short block size makes it vulnerable to
// birthday bound attacks (see https://sweet32.info). It should only be used
// where compatibility with legacy systems, not security, is the goal.
//
// Deprecated: any new system should use AES (from crypto/aes, if necessary in
// an AEAD mode like crypto/cipher.NewGCM) or XChaCha20-Poly1305 (from
// golang.org/x/crypto/chacha20poly1305).
package tea
import (
"crypto/cipher"
"encoding/binary"
"errors"
)
const (
// BlockSize is the size of a TEA block, in bytes.
BlockSize = 8
// KeySize is the size of a TEA key, in bytes.
KeySize = 16
// delta is the TEA key schedule constant.
delta = 0x9e3779b9
// numRounds is the standard number of rounds in TEA.
numRounds = 64
)
// tea is an instance of the TEA cipher with a particular key.
type tea struct {
key [16]byte
rounds int
}
// NewCipher returns an instance of the TEA cipher with the standard number of
// rounds. The key argument must be 16 bytes long.
func NewCipher(key []byte) (cipher.Block, error) {
return NewCipherWithRounds(key, numRounds)
}
// NewCipherWithRounds returns an instance of the TEA cipher with a given
// number of rounds, which must be even. The key argument must be 16 bytes
// long.
func NewCipherWithRounds(key []byte, rounds int) (cipher.Block, error) {
if len(key) != 16 {
return nil, errors.New("tea: incorrect key size")
}
if rounds&1 != 0 {
return nil, errors.New("tea: odd number of rounds specified")
}
c := &tea{
rounds: rounds,
}
copy(c.key[:], key)
return c, nil
}
// BlockSize returns the TEA block size, which is eight bytes. It is necessary
// to satisfy the Block interface in the package "crypto/cipher".
func (*tea) BlockSize() int {
return BlockSize
}
// Encrypt encrypts the 8 byte buffer src using the key in t and stores the
// result in dst. Note that for amounts of data larger than a block, it is not
// safe to just call Encrypt on successive blocks; instead, use an encryption
// mode like CBC (see crypto/cipher/cbc.go).
func (t *tea) Encrypt(dst, src []byte) {
e := binary.BigEndian
v0, v1 := e.Uint32(src), e.Uint32(src[4:])
k0, k1, k2, k3 := e.Uint32(t.key[0:]), e.Uint32(t.key[4:]), e.Uint32(t.key[8:]), e.Uint32(t.key[12:])
sum := uint32(0)
delta := uint32(delta)
for i := 0; i < t.rounds/2; i++ {
sum += delta
v0 += ((v1 << 4) + k0) ^ (v1 + sum) ^ ((v1 >> 5) + k1)
v1 += ((v0 << 4) + k2) ^ (v0 + sum) ^ ((v0 >> 5) + k3)
}
e.PutUint32(dst, v0)
e.PutUint32(dst[4:], v1)
}
// Decrypt decrypts the 8 byte buffer src using the key in t and stores the
// result in dst.
func (t *tea) Decrypt(dst, src []byte) {
e := binary.BigEndian
v0, v1 := e.Uint32(src), e.Uint32(src[4:])
k0, k1, k2, k3 := e.Uint32(t.key[0:]), e.Uint32(t.key[4:]), e.Uint32(t.key[8:]), e.Uint32(t.key[12:])
delta := uint32(delta)
sum := delta * uint32(t.rounds/2) // in general, sum = delta * n
for i := 0; i < t.rounds/2; i++ {
v1 -= ((v0 << 4) + k2) ^ (v0 + sum) ^ ((v0 >> 5) + k3)
v0 -= ((v1 << 4) + k0) ^ (v1 + sum) ^ ((v1 >> 5) + k1)
sum -= delta
}
e.PutUint32(dst, v0)
e.PutUint32(dst[4:], v1)
}
log/log.go
+80
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@@ -0,0 +1,80 @@
// Package log provides optional colored console logging, independent of decryption.
package log
import (
"fmt"
"os"
"path"
"runtime"
"sync"
"time"
)
// Logger writes timestamped, colorized log lines to stderr.
type Logger struct{}
// New returns a logger instance.
func New() *Logger { return &Logger{} }
func (l *Logger) Debug(a ...any) { output(1, "cyan", a...) }
func (l *Logger) Info(a ...any) { output(1, "green", a...) }
func (l *Logger) Warn(a ...any) { output(1, "yellow", a...) }
func (l *Logger) Error(a ...any) { output(1, "red", a...) }
// With returns the same logger (scope is ignored; kept for call-site compatibility).
func (l *Logger) With(_ any) *Logger { return l }
// PrintSuccess prints a green/cyan success line for CLI use.
func PrintSuccess(src, dst string) {
mu.Lock()
defer mu.Unlock()
fmt.Fprintf(os.Stderr, "%s %s: ", time.Now().Format("15:04:05.000"), trace(3))
fmt.Fprintf(os.Stderr, "操作成功: %s -> %s\n", green(src), cyan(dst))
}
var mu sync.Mutex
func output(skip int, color string, v ...any) {
mu.Lock()
defer mu.Unlock()
fmt.Fprint(os.Stderr, time.Now().Format("15:04:05.000"), " ", trace(skip+2), " ")
fmt.Fprintln(os.Stderr, colorize(color, fmt.Sprint(v...)))
}
func trace(skip int) string {
_, file, line, ok := runtime.Caller(skip)
if !ok {
return "unknown:0"
}
return fmt.Sprintf("%s:%d", path.Base(file), line)
}
func colorize(color, s string) string {
if !supportsColor() {
return s
}
const reset = "\033[0m"
switch color {
case "red":
return "\033[31m" + s + reset
case "green":
return "\033[32m" + s + reset
case "yellow":
return "\033[33m" + s + reset
case "cyan":
return "\033[36m" + s + reset
default:
return s
}
}
func green(s string) string { return colorize("green", s) }
func cyan(s string) string { return colorize("cyan", s) }
func supportsColor() bool {
if os.Getenv("NO_COLOR") != "" {
return false
}
// Windows 10+ and most Unix terminals support ANSI.
return true
}
misc/release.sh
+32
View File
@@ -0,0 +1,32 @@
#!/bin/bash
set -e
PLATFORMS=(
"linux/amd64"
"linux/arm64"
"darwin/amd64"
"darwin/arm64"
"windows/amd64"
"windows/386"
)
DEST_DIR=${DEST_DIR:-"dist"}
for PLATFORM in "${PLATFORMS[@]}"; do
GOOS=${PLATFORM%/*}
GOARCH=${PLATFORM#*/}
echo "Building for $GOOS/$GOARCH"
FILENAME="um-$GOOS-$GOARCH"
if [ "$GOOS" = "windows" ]; then
FILENAME="$FILENAME.exe"
fi
GOOS=$GOOS GOARCH=$GOARCH go build -v \
-o "${DEST_DIR}/${FILENAME}" \
-ldflags "-s -w -X main.AppVersion=$(git describe --tags --always --dirty)" \
./cmd/um
done
cd "$DEST_DIR"
sha256sum um-* > sha256sums.txt
mmkv/interface.go
+16
View File
@@ -0,0 +1,16 @@
package mmkv
type Manager interface {
// OpenVault opens a vault with the given id.
// If the vault does not exist, it will be created.
// If id is empty, DefaultVaultID will be used.
OpenVault(id string) (Vault, error)
OpenVaultCrypto(id string, cryptoKey string) (Vault, error)
}
type Vault interface {
Keys() []string
GetRaw(key string) ([]byte, bool)
GetBytes(key string) ([]byte, error)
GetString(key string) (string, error)
}
mmkv/internal/protobuffer.go
+41
View File
@@ -0,0 +1,41 @@
package internal
// ProtoBuffer decodes a subset of the protobuf wire format for MMKV payloads.
type ProtoBuffer struct {
buf []byte
idx int
}
// NewProtoBuffer returns a buffer whose unread portion is buf.
func NewProtoBuffer(buf []byte) *ProtoBuffer {
return &ProtoBuffer{buf: buf}
}
// DecodeStringBytes consumes a length-prefixed string.
func (b *ProtoBuffer) DecodeStringBytes() (string, error) {
v, n := ConsumeString(b.buf[b.idx:])
if n < 0 {
return "", parseError(n)
}
b.idx += n
return v, nil
}
// DecodeRawBytes consumes a length-prefixed bytes field.
func (b *ProtoBuffer) DecodeRawBytes(alloc bool) ([]byte, error) {
v, n := ConsumeBytes(b.buf[b.idx:])
if n < 0 {
return nil, parseError(n)
}
b.idx += n
if alloc {
v = append([]byte(nil), v...)
}
return v, nil
}
// Unread returns the unread portion of the buffer.
func (b *ProtoBuffer) Unread() []byte {
return b.buf[b.idx:]
}
mmkv/internal/wire.go
+65
View File
@@ -0,0 +1,65 @@
package internal
// Minimal protobuf wire helpers (bytes/string fields only).
const (
errCodeOverflow = -2
errCodeTruncated = -1
)
func consumeVarint(b []byte) (uint64, int) {
var x uint64
var s uint
for i, c := range b {
if c < 0x80 {
if i > 9 || i == 9 && c > 1 {
return 0, errCodeOverflow
}
return x | uint64(c)<<s, i + 1
}
x |= uint64(c&0x7f) << s
s += 7
}
return 0, errCodeTruncated
}
// ConsumeBytes parses a length-delimited bytes field.
func ConsumeBytes(b []byte) ([]byte, int) {
v, n := consumeVarint(b)
if n < 0 {
return nil, n
}
if v > uint64(len(b)-n) {
return nil, errCodeOverflow
}
return b[n : n+int(v)], n + int(v)
}
// ConsumeString parses a length-delimited string field.
func ConsumeString(b []byte) (string, int) {
v, n := ConsumeBytes(b)
if n < 0 {
return "", n
}
return string(v), n
}
func parseError(code int) error {
switch code {
case errCodeOverflow:
return errOverflow
case errCodeTruncated:
return errTruncated
default:
return errTruncated
}
}
var (
errOverflow = &parseErr{"overflow"}
errTruncated = &parseErr{"truncated"}
)
type parseErr struct{ msg string }
func (e *parseErr) Error() string { return "protowire: " + e.msg }
mmkv/manager.go
+96
View File
@@ -0,0 +1,96 @@
package mmkv
import (
"fmt"
"os"
"path"
)
const (
DefaultVaultID = "mmkv.default"
)
type manager struct {
dir string
vaults map[string]Vault
}
// NewManager creates a new MMKV Manager.
func NewManager(dir string) (Manager, error) {
// check dir exists
info, err := os.Stat(dir)
if err != nil {
return nil, fmt.Errorf("failed to stat dir: %w", err)
}
if !info.IsDir() {
return nil, fmt.Errorf("not a directory")
}
return &manager{
dir: dir,
vaults: make(map[string]Vault),
}, nil
}
func (m *manager) OpenVault(id string) (Vault, error) {
if id == "" {
id = DefaultVaultID
}
if v, ok := m.vaults[id]; ok {
return v, nil
}
vault, err := m.openVault(id, "")
if err != nil {
return nil, fmt.Errorf("failed to open vault: %w", err)
}
m.vaults[id] = vault
return vault, nil
}
func (m *manager) OpenVaultCrypto(id string, cryptoKey string) (Vault, error) {
if id == "" {
id = DefaultVaultID
}
if v, ok := m.vaults[id]; ok {
return v, nil
}
vault, err := m.openVault(id, cryptoKey)
if err != nil {
return nil, fmt.Errorf("failed to open vault: %w", err)
}
m.vaults[id] = vault
return vault, nil
}
func (m *manager) openVault(id string, cryptoKey string) (Vault, error) {
metaFile, err := os.Open(path.Join(m.dir, id+".crc"))
if err != nil {
return nil, fmt.Errorf("failed to open metadata file: %w", err)
}
defer metaFile.Close()
vaultFile, err := os.Open(path.Join(m.dir, id))
if err != nil {
return nil, fmt.Errorf("failed to open vault file: %w", err)
}
defer vaultFile.Close()
meta, err := loadMetadata(metaFile)
if err != nil {
return nil, fmt.Errorf("failed to load metadata: %w", err)
}
v, err := loadVault(vaultFile, meta, cryptoKey)
if err != nil {
return nil, fmt.Errorf("failed to load vault: %w", err)
}
return v, nil
}
mmkv/manager_test.go
+39
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@@ -0,0 +1,39 @@
package mmkv
import "testing"
func TestNewManager(t *testing.T) {
t.Run("Default", func(t *testing.T) {
mgr, err := NewManager("./testdata")
if err != nil {
t.Fatal(err)
}
vault, err := mgr.OpenVault("")
if err != nil {
t.Fatal(err)
}
if vault == nil {
t.Fatal("vault is nil")
}
})
t.Run("Crypto", func(t *testing.T) {
mgr, err := NewManager("./testdata")
if err != nil {
t.Fatal(err)
}
vault, err := mgr.OpenVaultCrypto("crypto", "123456")
if err != nil {
t.Fatal(err)
}
val, err := vault.GetString("world")
if err != nil {
t.Fatal(err)
}
if val != "hello" {
t.Fatalf("world = %q, want hello", val)
}
if _, err = vault.GetBytes("foo"); err == nil {
t.Fatal("expected error for missing key foo")
}
})
}
mmkv/metadata.go
+56
View File
@@ -0,0 +1,56 @@
package mmkv
import (
"encoding/binary"
"fmt"
"io"
)
type metadata struct {
// added in version 0
crc32 uint32
// added in version 1
version uint32
sequence uint32 // full write back count
// added in version 2
aesVector []byte // random iv for encryption, aes.BlockSize (16 bytes)
// added in version 3, try to reduce file corruption
actualSize uint32
lastActualSize uint32
lastCRC32 uint32
//_reversed []byte // 64 bytes
}
func loadMetadata(rd io.Reader) (*metadata, error) {
buf := make([]byte, 0x68)
_, err := io.ReadFull(rd, buf)
if err != nil {
return nil, fmt.Errorf("failed to read metadata: %w", err)
}
m := &metadata{}
m.crc32 = binary.LittleEndian.Uint32(buf[0:4])
m.version = binary.LittleEndian.Uint32(buf[4:8])
if m.version >= 1 {
m.sequence = binary.LittleEndian.Uint32(buf[8:12])
}
if m.version >= 2 {
m.aesVector = buf[12:28]
}
if m.version >= 3 {
m.actualSize = binary.LittleEndian.Uint32(buf[28:32])
m.lastActualSize = binary.LittleEndian.Uint32(buf[32:36])
m.lastCRC32 = binary.LittleEndian.Uint32(buf[36:40])
}
//m._reversed = buf[40:104]
return m, nil
}
mmkv/metadata_test.go
+42
View File
@@ -0,0 +1,42 @@
package mmkv
import (
"bytes"
"os"
"testing"
)
func Test_loadMetadata(t *testing.T) {
file, err := os.Open("./testdata/mmkv.default.crc")
if err != nil {
t.Fatal(err)
}
meta, err := loadMetadata(file)
if err != nil {
t.Fatal(err)
}
if meta.version != 3 {
t.Fatalf("version = %d, want 3", meta.version)
}
if meta.sequence != 1 {
t.Fatalf("sequence = %d, want 1", meta.sequence)
}
if meta.actualSize != 28 {
t.Fatalf("actualSize = %d, want 28", meta.actualSize)
}
if meta.crc32 != 197326043 {
t.Fatalf("crc32 = %d, want 197326043", meta.crc32)
}
if meta.lastActualSize != 4 {
t.Fatalf("lastActualSize = %d, want 4", meta.lastActualSize)
}
if meta.lastCRC32 != 1285129681 {
t.Fatalf("lastCRC32 = %d, want 1285129681", meta.lastCRC32)
}
wantIV := bytes.Repeat([]byte{0x00}, 16)
if !bytes.Equal(meta.aesVector, wantIV) {
t.Fatalf("aesVector = %v, want zeros", meta.aesVector)
}
}
mmkv/vault.go
+105
View File
@@ -0,0 +1,105 @@
package mmkv
import (
"crypto/aes"
"crypto/cipher"
"encoding/binary"
"fmt"
"hash/crc32"
"io"
"jsuse.com/dev/dec-music/mmkv/internal"
)
type vault map[string][]byte
func (v vault) keys() []string {
keys := make([]string, 0, len(v))
for k := range v {
keys = append(keys, k)
}
return keys
}
func (v vault) Keys() []string {
return v.keys()
}
func (v vault) GetRaw(key string) ([]byte, bool) {
val, ok := v[key]
return val, ok
}
func (v vault) GetBytes(key string) ([]byte, error) {
raw, ok := v[key]
if !ok {
return nil, fmt.Errorf("key not found: %s", key)
}
val, n := internal.ConsumeBytes(raw)
if n < 0 {
return nil, fmt.Errorf("invalid protobuf bytes")
}
return val, nil
}
func (v vault) GetString(key string) (string, error) {
val, err := v.GetBytes(key)
if err != nil {
return "", err
}
return string(val), nil
}
func loadVault(src io.Reader, m *metadata, cryptoKey string) (Vault, error) {
fileSizeBuf := make([]byte, 4)
_, err := io.ReadFull(src, fileSizeBuf)
if err != nil {
return nil, fmt.Errorf("failed to read file size: %w", err)
}
size := binary.LittleEndian.Uint32(fileSizeBuf)
if m != nil && size != m.actualSize {
return nil, fmt.Errorf("metadata and vault payload size mismatch")
}
buf := make([]byte, size)
_, err = io.ReadFull(src, buf)
if err != nil {
return nil, fmt.Errorf("failed to read file: %w", err)
}
if m != nil && m.crc32 != crc32.ChecksumIEEE(buf) {
return nil, fmt.Errorf("metadata and vault payload crc32 mismatch")
}
if len(cryptoKey) > 0 {
mKey := make([]byte, aes.BlockSize)
copy(mKey, cryptoKey)
block, err := aes.NewCipher(mKey)
if err != nil {
return nil, fmt.Errorf("failed to create aes cipher")
}
stream := cipher.NewCFBDecrypter(block, m.aesVector)
stream.XORKeyStream(buf, buf)
}
v := make(vault)
rd := internal.NewProtoBuffer(buf[4:])
for len(rd.Unread()) > 0 {
key, err := rd.DecodeStringBytes()
if err != nil {
return nil, fmt.Errorf("failed to decode key: %w", err)
}
val, err := rd.DecodeRawBytes(false)
if err != nil {
return nil, fmt.Errorf("failed to decode value: %w", err)
}
v[key] = val
}
return v, nil
}
mmkv/vault_test.go
+34
View File
@@ -0,0 +1,34 @@
package mmkv
import (
"os"
"testing"
)
func Test_loadVault(t *testing.T) {
file, err := os.Open("./testdata/mmkv.default")
if err != nil {
t.Fatal(err)
}
v, err := loadVault(file, nil, "")
if err != nil {
t.Fatal(err)
}
if len(v.Keys()) != 2 {
t.Fatalf("keys len = %d, want 2", len(v.Keys()))
}
val, err := v.GetString("world")
if err != nil {
t.Fatal(err)
}
if val != "hello" {
t.Fatalf("world = %q, want hello", val)
}
if _, err = v.GetBytes("foo"); err == nil {
t.Fatal("expected error for missing key foo")
}
}