aes解密错误fix

download.go

@@ -181,9 +181,9 @@ func (this *downloadEnv) RunDownload(req RunDownload_Req) (resp RunDownload_Resp
 		}
 	}
 	// 获取m3u8地址的内容体
-	tsKey, err := this.getM3u8Key(req.M3u8Url, string(m3u8Body))
+	encInfo, err := this.getEncryptInfo(req.M3u8Url, string(m3u8Body))
 	if err != nil {
-		resp.ErrMsg = "getM3u8Key: " + err.Error()
+		resp.ErrMsg = "getEncryptInfo: " + err.Error()
 		resp.IsCancel = this.GetIsCancel()
 		return resp
 	}
@@ -201,7 +201,7 @@ func (this *downloadEnv) RunDownload(req RunDownload_Req) (resp RunDownload_Resp
 	// 下载ts
 	this.SetProgressBarTitle("[4/6]下载ts")
 	this.speedSetBegin()
-	err = this.downloader(tsList, downloadDir, tsKey, req.ThreadCount)
+	err = this.downloader(tsList, downloadDir, encInfo, req.ThreadCount)
 	this.speedClearBytes()
 	if err != nil {
 		resp.ErrMsg = "下载ts文件错误: " + err.Error()
@@ -343,34 +343,31 @@ func GetWd() string {
 	return wd
 }
 
-// 获取m3u8加密的密钥
+// 获取m3u8加密的密钥, 可能存在iv
-func (this *downloadEnv) getM3u8Key(m3u8Url string, html string) (key string, err error) {
+func (this *downloadEnv) getEncryptInfo(m3u8Url string, html string) (info *EncryptInfo, err error) {
-	key = ""
+	keyPart := M3u8Parse(html).GetPart("#EXT-X-KEY")
-	for _, line := range splitLineWithTrimSpace(html) {
+	uri := keyPart.KeyValue["URI"]
-		if strings.Contains(line, "#EXT-X-KEY") == false {
+	if uri == "" {
-			continue
+		return nil, nil
-		}
-		uriPos := strings.Index(line, "URI")
-		quotationMarkPos := strings.LastIndex(line, "\"")
-		if uriPos == -1 || quotationMarkPos == -1 {
-			continue
-		}
-		keyUrl := strings.Split(line[uriPos:quotationMarkPos], "\"")[1]
-		if !strings.Contains(line, "http") {
-			var errMsg string
-			keyUrl, errMsg = resolveRefUrl(m3u8Url, line)
-			if errMsg != "" {
-				return "", errors.New(errMsg)
-			}
-		}
-		var res []byte
-		res, err = this.doGetRequest(keyUrl)
-		if err != nil {
-			return "", err
-		}
-		return string(res), nil
 	}
-	return "", nil
+	keyUrl, errMsg := resolveRefUrl(m3u8Url, uri)
+	if errMsg != "" {
+		return nil, errors.New(errMsg)
+	}
+	var res []byte
+	res, err = this.doGetRequest(keyUrl)
+	if err != nil {
+		return nil, err
+	}
+	iv, err := hex.DecodeString(strings.TrimPrefix(keyPart.KeyValue["IV"], "0x"))
+	if err != nil {
+		return nil, err
+	}
+	return &EncryptInfo{
+		Method: keyPart.KeyValue["METHOD"],
+		Key:    res,
+		Iv:     iv,
+	}, nil
 }
 
 func splitLineWithTrimSpace(s string) []string {
@@ -405,7 +402,7 @@ func getTsList(m38uUrl string, body string) (tsList []TsInfo, errMsg string) {
 
 // 下载ts文件
 // @modify: 2020-08-13 修复ts格式SyncByte合并不能播放问题
-func (this *downloadEnv) downloadTsFile(ts TsInfo, download_dir, key string) (err error) {
+func (this *downloadEnv) downloadTsFile(ts TsInfo, download_dir string, encInfo *EncryptInfo) (err error) {
 	currPath := fmt.Sprintf("%s/%s", download_dir, ts.Name)
 	if isFileExists(currPath) {
 		return nil
@@ -418,9 +415,9 @@ func (this *downloadEnv) downloadTsFile(ts TsInfo, download_dir, key string) (er
 	var origData []byte
 	origData = data
 	// 解密出视频 ts 源文件
-	if key != "" {
+	if encInfo != nil {
 		//解密 ts 文件，算法：aes 128 cbc pack5
-		origData, err = AesDecrypt(origData, []byte(key))
+		origData, err = AesDecrypt(origData, encInfo)
 		if err != nil {
 			return err
 		}
@@ -462,7 +459,7 @@ func (this *downloadEnv) SleepDur(d time.Duration) {
 	}
 }
 
-func (this *downloadEnv) downloader(tsList []TsInfo, downloadDir string, key string, threadCount int) (err error) {
+func (this *downloadEnv) downloader(tsList []TsInfo, downloadDir string, encInfo *EncryptInfo, threadCount int) (err error) {
 	if threadCount <= 0 || threadCount > 1000 {
 		return errors.New("downloadEnv.threadCount invalid: " + strconv.Itoa(threadCount))
 	}
@@ -487,7 +484,7 @@ func (this *downloadEnv) downloader(tsList []TsInfo, downloadDir string, key str
 					this.SleepDur(time.Second * time.Duration(i))
 					atomic.AddInt32(&this.sleepTh, -1)
 				}
-				lastErr = this.downloadTsFile(ts, downloadDir, key)
+				lastErr = this.downloadTsFile(ts, downloadDir, encInfo)
 				if lastErr == nil {
 					break
 				}
@@ -549,13 +546,20 @@ func PKCS7UnPadding(origData []byte) []byte {
 	return origData[:(length - unpadding)]
 }
 
-func AesDecrypt(crypted, key []byte) ([]byte, error) {
+func AesDecrypt(crypted []byte, encInfo *EncryptInfo) ([]byte, error) {
-	block, err := aes.NewCipher(key)
+	block, err := aes.NewCipher(encInfo.Key)
 	if err != nil {
 		return nil, err
 	}
 	blockSize := block.BlockSize()
-	blockMode := cipher.NewCBCDecrypter(block, key[:blockSize])
+	iv := encInfo.Iv
+	if len(iv) == 0 {
+		if len(encInfo.Key) > blockSize {
+			return nil, errors.New(fmt.Sprint("AesDecrypt invalid size ", blockSize, " ", len(encInfo.Key)))
+		}
+		iv = encInfo.Key[:blockSize]
+	}
+	blockMode := cipher.NewCBCDecrypter(block, iv)
 	origData := make([]byte, len(crypted))
 	blockMode.CryptBlocks(origData, crypted)
 	origData = PKCS7UnPadding(origData)

go.mod

@@ -8,7 +8,7 @@ require (
 	github.com/orestonce/gopool v0.0.0-20220508090328-d7d56d45b171
 	github.com/spf13/cobra v1.4.0
 	github.com/yapingcat/gomedia v0.0.0-20221023155149-c5f2f0f45ca5
-	golang.org/x/text v0.3.7
+	golang.org/x/text v0.3.3
 )
 
 require (

go.sum

@@ -14,8 +14,8 @@ github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/yapingcat/gomedia v0.0.0-20221023155149-c5f2f0f45ca5 h1:dswmlgf8sSrjaQJCGDpmI14sIkHqyIZdP6Jwzl7gVDY=
 github.com/yapingcat/gomedia v0.0.0-20221023155149-c5f2f0f45ca5/go.mod h1:WSZ59bidJOO40JSJmLqlkBJrjZCtjbKKkygEMfzY/kc=
-golang.org/x/text v0.3.7 h1:olpwvP2KacW1ZWvsR7uQhoyTYvKAupfQrRGBFM352Gk=
+golang.org/x/text v0.3.3 h1:cokOdA+Jmi5PJGXLlLllQSgYigAEfHXJAERHVMaCc2k=
-golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
+golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=

m3u8.go

@@ -0,0 +1,71 @@
+package m3u8d
+
+import (
+	"strconv"
+	"strings"
+)
+
+type EncryptInfo struct {
+	Method string
+	Key    []byte
+	Iv     []byte
+}
+
+type M3u8Content struct {
+	PartList []M3u8Part `json:",omitempty"`
+	TsList   []string   `json:",omitempty"`
+}
+
+type M3u8Part struct {
+	Tag      string            `json:",omitempty"`
+	TextFull string            `json:",omitempty"`
+	KeyValue map[string]string `json:",omitempty"`
+}
+
+func (info M3u8Content) GetPart(tag string) M3u8Part {
+	for _, one := range info.PartList {
+		if one.Tag == tag {
+			return one
+		}
+	}
+	return M3u8Part{}
+}
+
+func M3u8Parse(content string) (info M3u8Content) {
+	for _, line := range splitLineWithTrimSpace(content) {
+		if strings.HasPrefix(line, "#") == false {
+			continue
+		}
+		tmp := strings.SplitN(line, ":", 2)
+		if len(tmp) < 2 {
+			info.PartList = append(info.PartList, M3u8Part{
+				Tag: tmp[0],
+			})
+			continue
+		}
+		var p M3u8Part
+		p.Tag = tmp[0]
+		p.TextFull = strings.TrimSpace(tmp[1])
+		for _, kv := range strings.Split(tmp[1], ",") {
+			data := strings.SplitN(kv, "=", 2)
+			if len(data) < 2 {
+				continue
+			}
+			key := data[0]
+			value := strings.TrimSpace(data[1])
+			if strings.HasPrefix(value, "\"") {
+				var err error
+				value, err = strconv.Unquote(value)
+				if err != nil {
+					continue
+				}
+			}
+			if p.KeyValue == nil {
+				p.KeyValue = map[string]string{}
+			}
+			p.KeyValue[key] = value
+		}
+		info.PartList = append(info.PartList, p)
+	}
+	return info
+}

m3u8_test.go

@@ -0,0 +1,50 @@
+package m3u8d
+
+import (
+	"encoding/hex"
+	"strconv"
+	"strings"
+	"testing"
+)
+
+func TestM3u8Parse(t *testing.T) {
+	info := M3u8Parse(`#EXTM3U
+#EXT-X-VERSION:3
+#EXT-X-TARGETDURATION:6
+#EXT-X-PLAYLIST-TYPE:VOD
+#EXT-X-MEDIA-SEQUENCE:0
+#EXT-X-KEY:METHOD=AES-128,URI="/20230502/xthms/2000kb/hls/key.key"
+`)
+	part := info.GetPart("#EXT-X-KEY")
+	if part.KeyValue["METHOD"] != "AES-128" {
+		panic("method")
+	}
+	if part.KeyValue["URI"] != "/20230502/xthms/2000kb/hls/key.key" {
+		panic("uri")
+	}
+}
+
+func TestGetFileNameFromUrl(t *testing.T) {
+	{
+		part := M3u8Parse(`#EXT-X-KEY:IV=0x10c27a9e3fa363dfe4c44b59b67304b3`).GetPart("#EXT-X-KEY")
+		iv, err := hex.DecodeString(strings.TrimPrefix(part.KeyValue["IV"], "0x"))
+		checkErr(err)
+		if len(iv) != 16 {
+			panic("iv " + strconv.Quote(string(iv)))
+		}
+	}
+	{
+		part := M3u8Parse(`#EXT-X-KEY:nothing`).GetPart("#EXT-X-KEY")
+		iv, err := hex.DecodeString(strings.TrimPrefix(part.KeyValue["IV"], "0x"))
+		checkErr(err)
+		if len(iv) != 0 {
+			panic("iv " + strconv.Quote(string(iv)))
+		}
+	}
+}
+
+func checkErr(err error) {
+	if err != nil {
+		panic(err)
+	}
+}