From e90371922c33ee414d3df57ddca6cfb99a7aebe7 Mon Sep 17 00:00:00 2001
From: rlaphoenix <rlaphoenix@pm.me>
Date: Wed, 28 Sep 2022 06:21:28 +0100
Subject: [PATCH] PSSH: Add support for Key IDs of lengths other than 16 bytes

This is required for cases like Google's testing DASH manifests, e.g., 'tears' MPD. It assumes the Key ID as a number, which can support up to 16 bytes in this fashion (therefore technically 15 in our scenario as 16 byte Key_IDs can load normally).

Fixes #13
---
 pywidevine/pssh.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/pywidevine/pssh.py b/pywidevine/pssh.py
index b6ec5dc..6f275fd 100644
--- a/pywidevine/pssh.py
+++ b/pywidevine/pssh.py
@@ -199,7 +199,11 @@ class PSSH:
             cenc_header.ParseFromString(self.init_data)
             return [
                 # the key_ids value may or may not be hex underlying
-                UUID(bytes=key_id) if len(key_id) == 16 else UUID(hex=key_id.decode())
+                (
+                    UUID(bytes=key_id) if len(key_id) == 16 else  # normal
+                    UUID(hex=key_id.decode()) if len(key_id) == 32 else  # stored as hex
+                    UUID(int=int.from_bytes(key_id, "big"))  # assuming as number
+                )
                 for key_id in cenc_header.key_ids
             ]