custom pssh

alfg · Jun 12, 2017 · 6ef193e · 6ef193e
1 parent 07301d5
commit 6ef193e
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Showing 4 changed files with 259 additions and 1 deletion.
diff --git a/README.md b/README.md
@@ -1,6 +1,9 @@
 # Widevine
 Golang Client API and License Proxy for Widevine.
 
+## Protobuf
+`protoc.exe --go_out=. *.proto`
+
 ## Resources
 * https://www.widevine.com/product_news.html
 * https://storage.googleapis.com/wvdocs/Widevine_DRM_Getting_Started.pdf

diff --git a/license.go b/license.go
@@ -3,6 +3,10 @@ package widevine
 import (
 	"encoding/base64"
 	"encoding/json"
+	"fmt"
+
+	"github.com/alfg/widevine/pssh"
+	"github.com/golang/protobuf/proto"
 )
 
 const (
@@ -59,10 +63,20 @@ func New(opts Options) *Widevine {
 func (wp *Widevine) GetContentKey(contentID string) GetContentKeyResponse {
 	msg := wp.buildMessage(contentID)
 	resp := wp.sendRequest(msg)
+
+	enc := wp.buildPSSH(contentID)
+	fmt.Println("pssh  build:", enc)
 	return resp
 }
 
-func buildRequest() {
+func (wp *Widevine) buildPSSH(contentID string) string {
+	wvpssh := &pssh.WidevineCencHeader{
+		Provider:  proto.String(wp.Provider),
+		ContentId: []byte(contentID),
+	}
+	p, _ := proto.Marshal(wvpssh)
+
+	return base64.StdEncoding.EncodeToString(p)
 }
 
 func (wp *Widevine) buildMessage(contentID string) map[string]interface{} {

diff --git a/pssh/WidevineCencHeader.pb.go b/pssh/WidevineCencHeader.pb.go
diff --git a/pssh/WidevineCencHeader.proto b/pssh/WidevineCencHeader.proto
@@ -0,0 +1,41 @@
+syntax = "proto2";
+package pssh;
+
+message WidevineCencHeader {
+    enum Algorithm {
+        UNENCRYPTED = 0;
+        AESCTR = 1;
+    }
+    optional Algorithm algorithm = 1;
+    repeated bytes key_id = 2;
+
+    // Content provider name.
+    optional string provider = 3;
+
+    // A content identifier, specificed by content provider.
+    optional bytes content_id = 4;
+
+    // Track type. Acceptable values are SD, HD, and AUDIO. Used to
+    // differentiate content keys used by an asset.
+    optional string track_type_deprecated = 5;
+
+    // The name of a registered policy to be used for this asset.
+    optional string policy = 6;
+
+    // Crypto period index, for media using key rotation.
+    optional uint32 crypto_period_index = 7;
+
+    // Optional protected context for group content. The grouped_license is a
+    // serialized SignedMessage.
+    optional bytes grouped_license = 8;
+
+    // Protection scheme identifying the encryption algorithm.
+    // Represented as one of the following 4CC values:
+    // 'cenc' (AESCTR), 'cbc1' (AESCBC),
+    // 'cens' (AESCTR subsample), 'cbcs' (AESCBC subsample).
+    optional uint32 protection_scheme = 9;
+
+    // Optional. For media using key rotation, this represents the duration
+    // of each crypto period in seconds.
+    optional uint32 crypto_period_seconds = 10;
+}