CAS demo app

Adds a new `cas` directory to the ports/linux project. This contains an end-to-end demo of OEMCrypto CAS functionality, using the Linux tee_simulator as a base. Test: from ports/linux/cas dir: `CDM_DIR=~/work/cdm-dupe ./scripts/build.sh && CDM_DIR=~/work/cdm-dupe ./scripts/run.sh` Merged from https://widevine-internal-review.googlesource.com/178250 Change-Id: I781b403100ad2e069d99650d9ddae8e7acbc309a
2023-03-16 22:52:59 +00:00
parent 7d989e3448
commit 0dbc42f10e
3 changed files with 125 additions and 26 deletions
--- a/libwvdrmengine/oemcrypto/test/oemcrypto_test.cpp
+++ b/libwvdrmengine/oemcrypto/test/oemcrypto_test.cpp
@@ -1718,4 +1718,90 @@ TEST_F(OEMCryptoLoadsCertificate,
 /// @{

 /// @}
+
+#ifdef CAS_TEST
+
+#  include "tuner_hal.h"
+
+class OEMCryptoCasDemoTest : public OEMCryptoEntitlementLicenseTest {};
+
+TEST_P(OEMCryptoCasDemoTest, BasicFlow) {
+  // License contains entitlement keys, function reused from
+  // OEMCryptoEntitlementLicenseTest
+  LoadEntitlementLicense();
+  uint32_t key_session_id = 0;
+  ASSERT_EQ(OEMCrypto_SUCCESS, OEMCrypto_CreateEntitledKeySession(
+                                   session_.session_id(), &key_session_id));
+
+  EntitledMessage entitled_message(&license_messages_);
+
+  // Randomly generate entitled content keys
+  entitled_message.FillKeyArray();
+  if (session_.session_id() == key_session_id) {
+    GTEST_SKIP()
+        << "Skipping test because entitled and entitlement sessions are both "
+        << key_session_id << ".";
+  }
+  entitled_message.SetEntitledKeySession(key_session_id);
+
+  // Encrypt and load 0th key (even key) into OEMCrypto
+  ASSERT_NO_FATAL_FAILURE(entitled_message.LoadCasKeys(
+      /*load_even=*/true, /*load_odd=*/false, OEMCrypto_SUCCESS));
+
+  //
+  // Perform DecryptCTR() but for CAS
+  //
+  vector<uint8_t> unencrypted_data(256, 0);
+  vector<uint8_t> encrypted_data(256, 0);
+  vector<uint8_t> output_buffer(256, 0);
+  unencrypted_data.resize(encrypted_data.size());
+  output_buffer.resize(encrypted_data.size());
+
+  OEMCrypto_SampleDescription sample_description;
+  OEMCrypto_SubSampleDescription subsample_description;
+  GenerateSimpleSampleDescription(encrypted_data, output_buffer,
+                                  &sample_description, &subsample_description);
+
+  // Use 0th entitled content key and IV to encrypt test data
+  EncryptCTR(unencrypted_data,
+             entitled_message.entitled_key_data()->content_key_data,
+             entitled_message.entitled_key_data()->content_iv, &encrypted_data);
+
+  // Assume 0,0 pattern for CTR example
+  OEMCrypto_CENCEncryptPatternDesc pattern = {0, 0};
+
+  // Demo only -- copy IV into sample description so we can use
+  // WTPI_DecryptSample() in the Tuner decrypt impl. A real implementation would
+  // use the IV from the entitled content key, but the demo relies on the
+  // existing decrypt which uses SampleDescription IV.
+  memcpy(sample_description.iv,
+         entitled_message.entitled_key_data()->content_iv, 16);
+
+  // Get key token to send to Tuner for decrypt
+  std::vector<uint8_t> key_token;
+  size_t key_token_length = key_token.size();
+  OEMCryptoResult res = OEMCrypto_GetOEMKeyToken(
+      key_session_id, key_token.data(), &key_token_length);
+  if (res == OEMCrypto_ERROR_SHORT_BUFFER) {
+    key_token.resize(key_token_length);
+    res = OEMCrypto_GetOEMKeyToken(key_session_id, key_token.data(),
+                                   &key_token_length);
+  }
+  ASSERT_EQ(OEMCrypto_SUCCESS, res);
+
+  // Decrypt the data
+  ASSERT_EQ(TUNER_HAL_SUCCESS,
+            TunerHal_Decrypt(key_token.data(), key_token_length,
+                             TunerHal_KeyParityType_EvenKey,
+                             &sample_description,  // an array of samples.
+                             1,                    // the number of samples.
+                             &pattern));
+
+  ASSERT_EQ(unencrypted_data, output_buffer);
+}
+
+INSTANTIATE_TEST_SUITE_P(TestAll, OEMCryptoCasDemoTest,
+                         Range<uint32_t>(kCoreMessagesAPI, kCurrentAPI + 1));
+
+#endif
 }  // namespace wvoec