Add OEMCrypto_GenerateCertificateKeyPair second stage fuzzer

Merged from https://widevine-internal-review.googlesource.com/176771

Change-Id: I8afee6636a44f46a573be5a94f6c12161b57eace

libwvdrmengine/oemcrypto/test/fuzz_tests/oemcrypto_generate_certificate_key_pair_fuzz.cc

@@ -19,6 +19,38 @@ wvoec::OEMCryptoProvisioningAPIFuzz& provisioning_api_fuzz =
 extern "C" int LLVMFuzzerInitialize(int* argc, char*** argv) {
   wvoec::RedirectStdoutToFile();
   provisioning_api_fuzz.Initialize();
+
+#ifdef SECOND_STAGE
+
+  const uint32_t session_id = provisioning_api_fuzz.session().session_id();
+
+  size_t public_key_length = 0;
+  size_t public_key_signature_length = 0;
+  size_t wrapped_private_key_length = 0;
+  OEMCrypto_PrivateKeyType key_type = OEMCrypto_RSA_Private_Key;
+  OEMCryptoResult result = OEMCrypto_GenerateCertificateKeyPair(
+      session_id, nullptr, &public_key_length, nullptr,
+      &public_key_signature_length, nullptr, &wrapped_private_key_length,
+      &key_type);
+  wvoec::CheckStatusAndExitFuzzerOnFailure(result,
+                                           OEMCrypto_ERROR_SHORT_BUFFER);
+
+  std::vector<uint8_t> public_key(public_key_length);
+  std::vector<uint8_t> public_key_signature(public_key_signature_length);
+  std::vector<uint8_t> wrapped_private_key(wrapped_private_key_length);
+  result = OEMCrypto_GenerateCertificateKeyPair(
+      session_id, public_key.data(), &public_key_length,
+      public_key_signature.data(), &public_key_signature_length,
+      wrapped_private_key.data(), &wrapped_private_key_length, &key_type);
+  wvoec::CheckStatusAndExitFuzzerOnFailure(result, OEMCrypto_SUCCESS);
+
+  result = OEMCrypto_InstallOemPrivateKey(session_id, key_type,
+                                          wrapped_private_key.data(),
+                                          wrapped_private_key_length);
+  wvoec::CheckStatusAndExitFuzzerOnFailure(result, OEMCrypto_SUCCESS);
+
+#endif
+
   return 0;
 }