diff --git a/include/psa/crypto_struct.h b/include/psa/crypto_struct.h
index aee4002..94242f8 100644
--- a/include/psa/crypto_struct.h
+++ b/include/psa/crypto_struct.h
@@ -391,15 +391,19 @@
     return( attributes->core.lifetime );
 }
 
+static inline void psa_extend_key_usage_flags( psa_key_usage_t *usage_flags )
+{
+    if( *usage_flags & PSA_KEY_USAGE_SIGN_HASH )
+        *usage_flags |= PSA_KEY_USAGE_SIGN_MESSAGE;
+
+    if( *usage_flags & PSA_KEY_USAGE_VERIFY_HASH )
+        *usage_flags |= PSA_KEY_USAGE_VERIFY_MESSAGE;
+}
+
 static inline void psa_set_key_usage_flags(psa_key_attributes_t *attributes,
                                            psa_key_usage_t usage_flags)
 {
-    if( usage_flags & PSA_KEY_USAGE_SIGN_HASH )
-        usage_flags |= PSA_KEY_USAGE_SIGN_MESSAGE;
-
-    if( usage_flags & PSA_KEY_USAGE_VERIFY_HASH )
-        usage_flags |= PSA_KEY_USAGE_VERIFY_MESSAGE;
-
+    psa_extend_key_usage_flags( &usage_flags );
     attributes->core.policy.usage = usage_flags;
 }