From ab7c39a4502843bfbae83b50022d97d22bb8ed13 Mon Sep 17 00:00:00 2001
From: Cong Lin <conglin@google.com>
Date: Tue, 4 Apr 2023 10:04:30 -0700
Subject: [PATCH] OEMCrypto_ReassociateEntitledKeySession() to verify
 entitlement key IDs

OEMCrypto_ReassociateEntitledKeySession() should prevent an entitled key
session from being associated to an arbitrary entitlement session. The
target entitlement session is supposed to have all the entitlement keys
that the entitled key session uses.

Updated OPK and ref/testbed implementations.

Test: jenkins/opk_ta entitlement tests
Bug: 262795590
Merged from https://widevine-internal-review.googlesource.com/169774

Change-Id: I4322422f01f7094c3862f33ef3199ff3a44995b0
---
 .../oemcrypto/test/oemcrypto_test.cpp         | 28 +++++++++++++------
 1 file changed, 19 insertions(+), 9 deletions(-)

diff --git a/libwvdrmengine/oemcrypto/test/oemcrypto_test.cpp b/libwvdrmengine/oemcrypto/test/oemcrypto_test.cpp
index ae65061d..c627dc84 100644
--- a/libwvdrmengine/oemcrypto/test/oemcrypto_test.cpp
+++ b/libwvdrmengine/oemcrypto/test/oemcrypto_test.cpp
@@ -954,11 +954,7 @@ TEST_P(OEMCryptoEntitlementLicenseTest, ReassociateEntitledKeySessionAPI17) {
   ASSERT_NO_FATAL_FAILURE(license_messages_.CreateDefaultResponse());
   ASSERT_NO_FATAL_FAILURE(license_messages_.EncryptAndSignResponse());
   ASSERT_EQ(OEMCrypto_SUCCESS, license_messages_.LoadResponse());
-  // Setup another session.
-  Session session2;
-  ASSERT_NO_FATAL_FAILURE(session2.open());
-  ASSERT_NO_FATAL_FAILURE(InstallTestDrmKey(&session2));
-  ASSERT_NO_FATAL_FAILURE(session2.GenerateDerivedKeysFromSessionKey());
+
   // Setup an entitled key session in the first OEMCrypto session.
   uint32_t key_session_id;
   OEMCryptoResult sts = OEMCrypto_CreateEntitledKeySession(
@@ -969,7 +965,12 @@ TEST_P(OEMCryptoEntitlementLicenseTest, ReassociateEntitledKeySessionAPI17) {
   entitled_message.SetEntitledKeySession(key_session_id);
   ASSERT_NO_FATAL_FAILURE(entitled_message.LoadKeys(true));
 
-  // Now reassociate the entitled key session to the second OEMCrypto session.
+  // Setup another session.
+  Session session2;
+  ASSERT_NO_FATAL_FAILURE(session2.open());
+  ASSERT_NO_FATAL_FAILURE(InstallTestDrmKey(&session2));
+  // session2 does not have entitlement keys. Re-associating the entitled key
+  // session to session2 should fail
   OEMCryptoResult status = OEMCrypto_ReassociateEntitledKeySession(
       key_session_id, session2.session_id());
   if (status == OEMCrypto_ERROR_NOT_IMPLEMENTED &&
@@ -977,9 +978,18 @@ TEST_P(OEMCryptoEntitlementLicenseTest, ReassociateEntitledKeySessionAPI17) {
     GTEST_SKIP() << "Skipping test because "
                     "OEMCrypto_ReassociateEntitledKeySession not implemented.";
   }
-  ASSERT_EQ(OEMCrypto_SUCCESS, status);
-  // session2 does not have entitlement keys.
-  ASSERT_NO_FATAL_FAILURE(entitled_message.LoadKeys(false));
+  EXPECT_NE(OEMCrypto_SUCCESS, status);
+
+  // session2 loads the correct entitlement keys.
+  LicenseRoundTrip license_messages2(&session2);
+  license_messages2.set_license_type(OEMCrypto_EntitlementLicense);
+  ASSERT_NO_FATAL_FAILURE(license_messages2.SignAndVerifyRequest());
+  ASSERT_NO_FATAL_FAILURE(license_messages2.CreateDefaultResponse());
+  ASSERT_NO_FATAL_FAILURE(license_messages2.EncryptAndSignResponse());
+  ASSERT_EQ(OEMCrypto_SUCCESS, license_messages2.LoadResponse());
+  // Re-associating to session2 should succeed.
+  ASSERT_EQ(OEMCrypto_SUCCESS, OEMCrypto_ReassociateEntitledKeySession(
+                                   key_session_id, session2.session_id()));
 
   // Now reassociate the entitled key session back to the first OEMCrypto
   // session.