Add crypto service

Change-Id: Ifd55a4caaf0b95e3d1b6504863fba112a7e18f15
Signed-off-by: Julian Hall <julian.hall@arm.com>
diff --git a/protocols/service/crypto/protobuf/generate_key.proto b/protocols/service/crypto/protobuf/generate_key.proto
new file mode 100644
index 0000000..48025a6
--- /dev/null
+++ b/protocols/service/crypto/protobuf/generate_key.proto
@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2020, Arm Limited and Contributors. All rights reserved.
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+syntax = "proto3";
+
+package ts_crypto;
+
+import "service/crypto/protobuf/key_attributes.proto";
+
+message GenerateKeyIn {
+  KeyAttributes attributes = 1;
+}
+
+message GenerateKeyOut {
+  uint32 handle = 1;
+}