diff --git a/staging/security/see/hwcrypto/aidl/aidl_api/android.hardware.security.see/current/android/hardware/security/see/hwcrypto/types/ExplicitKeyMaterial.aidl b/staging/security/see/hwcrypto/aidl/aidl_api/android.hardware.security.see/current/android/hardware/security/see/hwcrypto/types/ExplicitKeyMaterial.aidl
index 933fb67..9970678 100644
--- a/staging/security/see/hwcrypto/aidl/aidl_api/android.hardware.security.see/current/android/hardware/security/see/hwcrypto/types/ExplicitKeyMaterial.aidl
+++ b/staging/security/see/hwcrypto/aidl/aidl_api/android.hardware.security.see/current/android/hardware/security/see/hwcrypto/types/ExplicitKeyMaterial.aidl
@@ -34,4 +34,5 @@
 package android.hardware.security.see.hwcrypto.types;
 union ExplicitKeyMaterial {
   android.hardware.security.see.hwcrypto.types.AesKey aes;
+  android.hardware.security.see.hwcrypto.types.HmacKey hmac;
 }
diff --git a/staging/security/see/hwcrypto/aidl/aidl_api/android.hardware.security.see/current/android/hardware/security/see/hwcrypto/types/HmacKey.aidl b/staging/security/see/hwcrypto/aidl/aidl_api/android.hardware.security.see/current/android/hardware/security/see/hwcrypto/types/HmacKey.aidl
new file mode 100644
index 0000000..f8de94a
--- /dev/null
+++ b/staging/security/see/hwcrypto/aidl/aidl_api/android.hardware.security.see/current/android/hardware/security/see/hwcrypto/types/HmacKey.aidl
@@ -0,0 +1,38 @@
+/*
+ * Copyright 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+///////////////////////////////////////////////////////////////////////////////
+// THIS FILE IS IMMUTABLE. DO NOT EDIT IN ANY CASE.                          //
+///////////////////////////////////////////////////////////////////////////////
+
+// This file is a snapshot of an AIDL file. Do not edit it manually. There are
+// two cases:
+// 1). this is a frozen version file - do not edit this in any case.
+// 2). this is a 'current' file. If you make a backwards compatible change to
+//     the interface (from the latest frozen version), the build system will
+//     prompt you to update this file with `m <name>-update-api`.
+//
+// You must not make a backward incompatible change to any AIDL file built
+// with the aidl_interface module type with versions property set. The module
+// type is used to build AIDL files in a way that they can be used across
+// independently updatable components of the system. If a device is shipped
+// with such a backward incompatible change, it has a high risk of breaking
+// later when a module using the interface is updated, e.g., Mainline modules.
+
+package android.hardware.security.see.hwcrypto.types;
+union HmacKey {
+  byte[32] sha256 = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
+  byte[64] sha512;
+}
diff --git a/staging/security/see/hwcrypto/aidl/android/hardware/security/see/hwcrypto/types/ExplicitKeyMaterial.aidl b/staging/security/see/hwcrypto/aidl/android/hardware/security/see/hwcrypto/types/ExplicitKeyMaterial.aidl
index 4298ba9..3aa5611 100644
--- a/staging/security/see/hwcrypto/aidl/android/hardware/security/see/hwcrypto/types/ExplicitKeyMaterial.aidl
+++ b/staging/security/see/hwcrypto/aidl/android/hardware/security/see/hwcrypto/types/ExplicitKeyMaterial.aidl
@@ -16,10 +16,12 @@
 package android.hardware.security.see.hwcrypto.types;
 
 import android.hardware.security.see.hwcrypto.types.AesKey;
+import android.hardware.security.see.hwcrypto.types.HmacKey;
 
 /*
  * Type encapsulating a clear key.
  */
 union ExplicitKeyMaterial {
     AesKey aes;
+    HmacKey hmac;
 }
diff --git a/staging/security/see/hwcrypto/aidl/android/hardware/security/see/hwcrypto/types/HmacKey.aidl b/staging/security/see/hwcrypto/aidl/android/hardware/security/see/hwcrypto/types/HmacKey.aidl
new file mode 100644
index 0000000..a0b6ba7
--- /dev/null
+++ b/staging/security/see/hwcrypto/aidl/android/hardware/security/see/hwcrypto/types/HmacKey.aidl
@@ -0,0 +1,32 @@
+/*
+ * Copyright 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package android.hardware.security.see.hwcrypto.types;
+
+/*
+ * Type that represents an Hmac key.
+ */
+union HmacKey {
+    /*
+     * Raw Hmac key for use with sha256.
+     */
+    byte[32] sha256 = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            0, 0, 0, 0, 0, 0};
+
+    /*
+     * Raw Hmac key for use with sha512.
+     */
+    byte[64] sha512;
+}