From bf6376aabcad62f95257492afd5d25c60272a4de Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=81lvaro=20Velad=20Galv=C3=A1n?= <ladvan91@hotmail.com>
Date: Tue, 31 Dec 2024 14:51:07 +0100
Subject: [PATCH] fix: Fix ClearKey license on old CDMs (#7816)

Backported to v4.12.x
---
 lib/media/drm_engine.js     | 47 ++++++++++++++++++++++++++++++++++++-
 lib/util/drm_utils.js       | 20 ++++++++++++++++
 test/util/drm_utils_unit.js | 32 +++++++++++++++++++++++++
 3 files changed, 98 insertions(+), 1 deletion(-)

diff --git a/lib/media/drm_engine.js b/lib/media/drm_engine.js
index a5dbeb2e06f..facfc17f41b 100644
--- a/lib/media/drm_engine.js
+++ b/lib/media/drm_engine.js
@@ -1433,7 +1433,12 @@ shaka.media.DrmEngine = class {
     }
     // NOTE: allowCrossSiteCredentials can be set in a request filter.
 
-    if (shaka.util.DrmUtils.isPlayReadyKeySystem(
+    if (shaka.drm.DrmUtils.isClearKeySystem(
+        this.currentDrmInfo_.keySystem)) {
+      this.fixClearKeyRequest_(request, this.currentDrmInfo_);
+    }
+
+    if (shaka.drm.DrmUtils.isPlayReadyKeySystem(
         this.currentDrmInfo_.keySystem)) {
       this.unpackPlayReadyRequest_(request);
     }
@@ -1584,6 +1589,31 @@ shaka.media.DrmEngine = class {
         /** @type{string} */(shaka.util.TXml.getTextContents(challenge)));
   }
 
+  /**
+   * Some old ClearKey CDMs don't include the type in the body request.
+   *
+   * @param {shaka.extern.Request} request
+   * @param {shaka.extern.DrmInfo} drmInfo
+   * @private
+   */
+  fixClearKeyRequest_(request, drmInfo) {
+    try {
+      const body = shaka.util.StringUtils.fromBytesAutoDetect(request.body);
+      if (body) {
+        const licenseBody =
+          /** @type {shaka.drm.DrmEngine.ClearKeyLicenceRequestFormat} */ (
+            JSON.parse(body));
+        if (!licenseBody.type) {
+          licenseBody.type = drmInfo.sessionType;
+          request.body =
+              shaka.util.StringUtils.toUTF8(JSON.stringify(licenseBody));
+        }
+      }
+    } catch (e) {
+      shaka.log.info('Error unpacking ClearKey license', e);
+    }
+  }
+
   /**
    * @param {!Event} event
    * @private
@@ -2603,6 +2633,21 @@ shaka.media.DrmEngine.SessionMetaData;
  */
 shaka.media.DrmEngine.PlayerInterface;
 
+/**
+ * @typedef {{
+ *   kids: !Array.<string>,
+ *   type: string
+ * }}
+ *
+ * @property {!Array.<string>} kids
+ *   An array of key IDs. Each element of the array is the base64url encoding of
+ *   the octet sequence containing the key ID value.
+ * @property {string} type
+ *   The requested MediaKeySessionType.
+ * @see https://www.w3.org/TR/encrypted-media/#clear-key-request-format
+ */
+shaka.drm.DrmEngine.ClearKeyLicenceRequestFormat;
+
 /**
  * The amount of time, in seconds, we wait to consider a session closed.
  * This allows us to work around Chrome bug https://crbug.com/1108158.
diff --git a/lib/util/drm_utils.js b/lib/util/drm_utils.js
index 3bee650c000..2fead5d1b37 100644
--- a/lib/util/drm_utils.js
+++ b/lib/util/drm_utils.js
@@ -113,6 +113,26 @@ shaka.util.DrmUtils = class {
     return drmInfo ? drmInfo.keySystem : '';
   }
 
+  /**
+   * @param {?string} keySystem
+   * @return {boolean}
+   */
+  static isClearKeySystem(keySystem) {
+    return keySystem === 'org.w3.clearkey';
+  }
+
+  /**
+   * @param {?string} keySystem
+   * @return {boolean}
+   */
+  static isWidevineKeySystem(keySystem) {
+    if (keySystem) {
+      return !!keySystem.match(/^com\.widevine\.alpha/);
+    }
+
+    return false;
+  }
+
   /**
    * @param {?string} keySystem
    * @return {boolean}
diff --git a/test/util/drm_utils_unit.js b/test/util/drm_utils_unit.js
index c87ecc2fa57..a10e61e5260 100644
--- a/test/util/drm_utils_unit.js
+++ b/test/util/drm_utils_unit.js
@@ -143,6 +143,38 @@ describe('DrmUtils', () => {
     });
   }); // describe('getCommonDrmInfos')
 
+  describe('isClearKeySystem', () => {
+    it('should return true for ClearKey', () => {
+      expect(shaka.drm.DrmUtils.isClearKeySystem(
+          'org.w3.clearkey')).toBe(true);
+    });
+
+    it('should return false for non-ClearKey key systems', () => {
+      expect(shaka.drm.DrmUtils.isClearKeySystem(
+          'com.widevine.alpha')).toBe(false);
+      expect(shaka.drm.DrmUtils.isClearKeySystem(
+          'com.microsoft.playready')).toBe(false);
+      expect(shaka.drm.DrmUtils.isClearKeySystem(
+          'com.apple.fps')).toBe(false);
+    });
+  });
+
+  describe('isWidevineKeySystem', () => {
+    it('should return true for Widevine', () => {
+      expect(shaka.drm.DrmUtils.isWidevineKeySystem(
+          'com.widevine.alpha')).toBe(true);
+      expect(shaka.drm.DrmUtils.isWidevineKeySystem(
+          'com.widevine.alpha.anything')).toBe(true);
+    });
+
+    it('should return false for non-Widevine key systems', () => {
+      expect(shaka.drm.DrmUtils.isWidevineKeySystem(
+          'com.microsoft.playready')).toBe(false);
+      expect(shaka.drm.DrmUtils.isWidevineKeySystem(
+          'com.apple.fps')).toBe(false);
+    });
+  });
+
   describe('isPlayReadyKeySystem', () => {
     it('should return true for MS & Chromecast PlayReady', () => {
       expect(shaka.util.DrmUtils.isPlayReadyKeySystem(