diff --git a/include/psa/crypto_builtin_composites.h b/include/psa/crypto_builtin_composites.h
index a22a997..16fa3db 100644
--- a/include/psa/crypto_builtin_composites.h
+++ b/include/psa/crypto_builtin_composites.h
@@ -51,4 +51,32 @@
 } psa_hmac_internal_data;
 #endif /* MBEDTLS_MD_C */
 
+#include "mbedtls/cmac.h"
+
+#if defined(MBEDTLS_PSA_BUILTIN_ALG_CMAC) || \
+    defined(MBEDTLS_PSA_BUILTIN_ALG_HMAC)
+#define MBEDTLS_PSA_BUILTIN_MAC
+#endif
+
+typedef struct
+{
+    psa_algorithm_t alg;
+    /* To be fleshed out in a later commit. */
+} mbedtls_psa_mac_operation_t;
+
+#define MBEDTLS_PSA_MAC_OPERATION_INIT {0, {0}}
+
+/*
+ * BEYOND THIS POINT, TEST DRIVER DECLARATIONS ONLY.
+ */
+#if defined(PSA_CRYPTO_DRIVER_TEST)
+
+typedef mbedtls_psa_mac_operation_t mbedtls_transparent_test_driver_mac_operation_t;
+typedef mbedtls_psa_mac_operation_t mbedtls_opaque_test_driver_mac_operation_t;
+
+#define MBEDTLS_TRANSPARENT_TEST_DRIVER_MAC_OPERATION_INIT MBEDTLS_PSA_MAC_OPERATION_INIT
+#define MBEDTLS_OPAQUE_TEST_DRIVER_MAC_OPERATION_INIT MBEDTLS_PSA_MAC_OPERATION_INIT
+
+#endif /* PSA_CRYPTO_DRIVER_TEST */
+
 #endif /* PSA_CRYPTO_BUILTIN_COMPOSITES_H */
diff --git a/include/psa/crypto_driver_contexts_composites.h b/include/psa/crypto_driver_contexts_composites.h
index 1c71c52..239fdcb 100644
--- a/include/psa/crypto_driver_contexts_composites.h
+++ b/include/psa/crypto_driver_contexts_composites.h
@@ -49,5 +49,14 @@
  * are formatted as `'drivername'_ctx`. This allows for procedural generation
  * of both this file and the content of psa_crypto_driver_wrappers.c */
 
+typedef union {
+    unsigned dummy; /* Make sure this union is always non-empty */
+    mbedtls_psa_mac_operation_t mbedtls_ctx;
+#if defined(PSA_CRYPTO_DRIVER_TEST)
+    mbedtls_transparent_test_driver_mac_operation_t transparent_test_driver_ctx;
+    mbedtls_opaque_test_driver_mac_operation_t opaque_test_driver_ctx;
+#endif
+} psa_driver_mac_context_t;
+
 #endif /* PSA_CRYPTO_DRIVER_CONTEXTS_COMPOSITES_H */
 /* End of automatically generated file. */
diff --git a/include/psa/crypto_struct.h b/include/psa/crypto_struct.h
index 58f2c67..975e9f7 100644
--- a/include/psa/crypto_struct.h
+++ b/include/psa/crypto_struct.h
@@ -137,6 +137,7 @@
     unsigned int has_input : 1;
     unsigned int is_sign : 1;
     uint8_t mac_size;
+    unsigned int id;
     union
     {
         unsigned dummy; /* Make the union non-empty even with no supported algorithms. */
@@ -146,10 +147,11 @@
 #if defined(MBEDTLS_CMAC_C)
         mbedtls_cipher_context_t cmac;
 #endif
+        psa_driver_mac_context_t driver;
     } ctx;
 };
 
-#define PSA_MAC_OPERATION_INIT {0, 0, 0, 0, 0, 0, 0, {0}}
+#define PSA_MAC_OPERATION_INIT {0, 0, 0, 0, 0, 0, 0, 0, {0}}
 static inline struct psa_mac_operation_s psa_mac_operation_init( void )
 {
     const struct psa_mac_operation_s v = PSA_MAC_OPERATION_INIT;