nrf_security: cracen: make IKG seed KMU slot configurable

doc/nrf/releases_and_maturity/migration/migration_guide_2.8.rst

@@ -85,13 +85,15 @@ SUIT DFU for nRF54H20
 Nordic Secure Immutable Bootloader (NSIB, B0, or B0n)
 -----------------------------------------------------
 
-Custom printing has been dropped in favor of using the logging subsystem, with output printed out to the default logging device.
-The ``CONFIG_SECURE_BOOT_DEBUG`` Kconfig option has been removed.
-To disable logging in B0 or B0n, set the :kconfig:option:`CONFIG_LOG` option to ``n``.
-To send logs over RTT instead of UART, apply the following settings:
+.. toggle::
+
+   Custom printing has been dropped in favor of using the logging subsystem, with output printed out to the default logging device.
+   The ``CONFIG_SECURE_BOOT_DEBUG`` Kconfig option has been removed.
+   To disable logging in B0 or B0n, set the :kconfig:option:`CONFIG_LOG` option to ``n``.
+   To send logs over RTT instead of UART, apply the following settings:
 
-    * Enable the :kconfig:option:`CONFIG_USE_SEGGER_RTT` and :kconfig:option:`CONFIG_RTT_CONSOLE` Kconfig options.
-    * Disable the :kconfig:option:`CONFIG_UART_CONSOLE` and :kconfig:option:`CONFIG_SERIAL` Kconfig options.
+       * Enable the :kconfig:option:`CONFIG_USE_SEGGER_RTT` and :kconfig:option:`CONFIG_RTT_CONSOLE` Kconfig options.
+       * Disable the :kconfig:option:`CONFIG_UART_CONSOLE` and :kconfig:option:`CONFIG_SERIAL` Kconfig options.
 
 Libraries
 =========
@@ -120,6 +122,13 @@ AT command parser
 
   * The :c:func:`at_parser_cmd_type_get` has been renamed to :c:func:`at_parser_at_cmd_type_get`.
 
+nRF Security
+------------
+
+.. toggle::
+
+   * The ``CONFIG_CRACEN_LOAD_KMU_SEED`` Kconfig option was renamed to :kconfig:option:`CONFIG_CRACEN_IKG_SEED_LOAD`.
+
 .. _migration_2.8_recommended:
 
 Recommended changes
@@ -359,4 +368,6 @@ This section provides detailed lists of changes by :ref:`protocol <protocols>`.
 Bluetooth® LE
 -------------
 
-*  To use the Zephyr Bluetooth LE Controller, use the :ref:`bt-ll-sw-split <zephyr:snippet-bt-ll-sw-split>` snippet (see :ref:`app_build_snippets`).
+.. toggle::
+
+   *  To use the Zephyr Bluetooth LE Controller, use the :ref:`bt-ll-sw-split <zephyr:snippet-bt-ll-sw-split>` snippet (see :ref:`app_build_snippets`).

doc/nrf/releases_and_maturity/releases/release-notes-changelog.rst

@@ -97,7 +97,7 @@ Developing with PMICs
 Security
 ========
 
-|no_changes_yet_note|
+* The :kconfig:option:`CONFIG_CRACEN_IKG_SEED_KMU_SLOT` Kconfig option was added to allow customization of the KMU slot used to store CRACEN's Internal Key Generator (IKG) seed.
 
 Protocols
 =========

lib/hw_unique_key/hw_unique_key_cracen.c

@@ -63,11 +63,13 @@ int hw_unique_key_derive_key(enum hw_unique_key_slot key_slot, const uint8_t *co
 
 bool hw_unique_key_are_any_written(void)
 {
-
 	psa_key_lifetime_t lifetime;
 	psa_drv_slot_number_t slot_number;
-	mbedtls_svc_key_id_t key_id = mbedtls_svc_key_id_make(
-		0, PSA_KEY_HANDLE_FROM_CRACEN_KMU_SLOT(CRACEN_KMU_KEY_USAGE_SCHEME_SEED, 0));
+	mbedtls_svc_key_id_t key_id;
+
+	key_id = mbedtls_svc_key_id_make(0, PSA_KEY_HANDLE_FROM_CRACEN_KMU_SLOT(
+						KMU_METADATA_SCHEME_SEED,
+						CONFIG_CRACEN_IKG_SEED_KMU_SLOT));
 	return cracen_kmu_get_key_slot(key_id, &lifetime, &slot_number) == PSA_SUCCESS;
 }
 
@@ -83,11 +85,12 @@ int hw_unique_key_write(enum hw_unique_key_slot key_slot, const uint8_t *key)
 
 	psa_set_key_id(&seed_attr,
 		       mbedtls_svc_key_id_make(0, PSA_KEY_HANDLE_FROM_CRACEN_KMU_SLOT(
-							  CRACEN_KMU_KEY_USAGE_SCHEME_SEED, 0)));
+							KMU_METADATA_SCHEME_SEED,
+							CONFIG_CRACEN_IKG_SEED_KMU_SLOT)));
 	psa_set_key_type(&seed_attr, PSA_KEY_TYPE_RAW_DATA);
-	psa_set_key_lifetime(&seed_attr,
-			     PSA_KEY_LIFETIME_FROM_PERSISTENCE_AND_LOCATION(
-				     PSA_KEY_PERSISTENCE_DEFAULT, PSA_KEY_LOCATION_CRACEN_KMU));
+	psa_set_key_lifetime(&seed_attr, PSA_KEY_LIFETIME_FROM_PERSISTENCE_AND_LOCATION(
+							PSA_KEY_PERSISTENCE_DEFAULT,
+							PSA_KEY_LOCATION_CRACEN_KMU));
 
 	status = cracen_import_key(&seed_attr, key, HUK_SIZE_BYTES, opaque_buffer,
 				   sizeof(opaque_buffer), &outlen, &key_bits);
@@ -102,6 +105,7 @@ int hw_unique_key_write(enum hw_unique_key_slot key_slot, const uint8_t *key)
 
 	return HW_UNIQUE_KEY_SUCCESS;
 }
+
 int hw_unique_key_write_random(void)
 {
 	psa_status_t status;
@@ -112,7 +116,7 @@ int hw_unique_key_write_random(void)
 		return -HW_UNIQUE_KEY_ERR_GENERATION_FAILED;
 	}
 
-	return hw_unique_key_write(0, random_data);
+	return hw_unique_key_write(/* unused */ -1, random_data);
 }
 
 bool hw_unique_key_is_written(enum hw_unique_key_slot key_slot)

subsys/nrf_security/src/drivers/cracen/Kconfig

@@ -31,18 +31,26 @@ config CRACEN_LIB_KMU
 	help
 	  The CRACEN KMU library.
 
-config CRACEN_LOAD_KMU_SEED
-	bool
-	prompt "Load the CRACEN IKG seed"
+config CRACEN_IKG_SEED_LOAD
+	bool "Load the CRACEN IKG seed"
 	depends on CRACEN_LIB_KMU
 	default y
 	help
-	  Configuration to load a The CRACEN IKG seed value from KMU.
-	  The KMU seed is used to give support for key derived from IKG.
+	  The IKG seed is used to derive the keys in the IKG.
 	  If there is no seed in KMU, it is expected to be generated.
 	  Note that this is not required to be used if a bootloader is loading
 	  KMU seed.
 
+config CRACEN_IKG_SEED_KMU_SLOT
+	int "KMU slot of the CRACEN IKG seed"
+	range 0 183
+	default 183
+	help
+	  The CRACEN IKG seed spans over 3 KMU slots:
+	  the one defined here and the two subsequent ones.
+	  This defines the KMU slot (along with the two following it) to which
+	  the IKG seed is provisioned and that is pushed when loading the IKG seed.
+
 rsource 'psa_driver.Kconfig'
 
 endif # PSA_CRYPTO_DRIVER_CRACEN

subsys/nrf_security/src/drivers/cracen/common/include/cracen/lib_kmu.h

@@ -64,9 +64,9 @@ struct kmu_src_t {
 	/** Revocation policy. */
 	uint32_t rpolicy;
 	/** 32-bit destination address. Cannot point to SICR and must be on a
-	 * 64-bit boundary.
+	 * 128-bit boundary.
 	 */
-	uint64_t *dest;
+	uint8_t *dest;
 	/** 32 bits of any clear-text metadata that belongs with the key slot.
 	 */
 	uint32_t metadata;

subsys/nrf_security/src/drivers/cracen/cracenpsa/include/cracen_psa_kmu.h

@@ -34,10 +34,26 @@ typedef uint64_t psa_drv_slot_number_t;
 /* Retrieve KMU slot number for PSA key id. */
 #define CRACEN_PSA_GET_KMU_SLOT(key_id) ((key_id)&0xff)
 
-#define CRACEN_KMU_KEY_USAGE_SCHEME_PROTECTED 0
-#define CRACEN_KMU_KEY_USAGE_SCHEME_SEED      1
-#define CRACEN_KMU_KEY_USAGE_SCHEME_ENCRYPTED 2
-#define CRACEN_KMU_KEY_USAGE_SCHEME_RAW	      3
+enum kmu_metadata_key_usage_scheme {
+	/**
+	 * These keys can only be pushed to CRACEN's protected RAM.
+	 * The keys are not encrypted. Only AES supported.
+	 */
+	KMU_METADATA_SCHEME_PROTECTED,
+	/**
+	 * CRACEN's IKG seed uses 3 key slots. Pushed to the seed register.
+	 */
+	KMU_METADATA_SCHEME_SEED,
+	/**
+	 * These keys are stored in encrypted form. They will be decrypted
+	 * to @ref kmu_push_area for usage.
+	 */
+	KMU_METADATA_SCHEME_ENCRYPTED,
+	/**
+	 * These keys are not encrypted. Pushed to @ref kmu_push_area.
+	 */
+	KMU_METADATA_SCHEME_RAW
+};
 
 /**
  * @brief Retrieves the slot number for a given key handle.

subsys/nrf_security/src/drivers/cracen/cracenpsa/src/common.c

@@ -659,9 +659,11 @@ int cracen_signature_get_rsa_key(struct si_rsa_key *rsa, bool extract_pubkey, bo
 
 int cracen_prepare_ik_key(const uint8_t *user_data)
 {
-#ifdef CONFIG_CRACEN_LOAD_KMU_SEED
+#ifdef CONFIG_CRACEN_IKG_SEED_LOAD
 	if (!nrf_cracen_seedram_lock_check(NRF_CRACEN)) {
-		if (lib_kmu_push_slot(0) || lib_kmu_push_slot(1) || lib_kmu_push_slot(2)) {
+		if (lib_kmu_push_slot(CONFIG_CRACEN_IKG_SEED_KMU_SLOT + 0) ||
+		    lib_kmu_push_slot(CONFIG_CRACEN_IKG_SEED_KMU_SLOT + 1) ||
+		    lib_kmu_push_slot(CONFIG_CRACEN_IKG_SEED_KMU_SLOT + 2)) {
 			return SX_ERR_INVALID_KEYREF;
 		}
 		nrf_cracen_seedram_lock_enable_set(NRF_CRACEN, true);

subsys/nrf_security/src/drivers/cracen/cracenpsa/src/cracen.c

@@ -58,7 +58,7 @@ void cracen_acquire(void)
 							     CRACEN_ENABLE_RNG_Msk |
 							     CRACEN_ENABLE_PKEIKG_Msk);
 		irq_enable(CRACEN_IRQn);
-		LOG_DBG_MSG("Power on CRACEN.");
+		LOG_DBG_MSG("Powered on CRACEN.");
 	}
 
 	nrf_security_mutex_unlock(cracen_mutex);

subsys/nrf_security/src/drivers/cracen/cracenpsa/src/kmu.c

@@ -14,8 +14,8 @@
 #include <sxsymcrypt/internal.h>
 #include <zephyr/sys/util.h>
 #include <zephyr/sys/__assert.h>
-
-#include "cracen_psa.h"
+#include <hw_unique_key.h>
+#include <cracen_psa.h>
 #include "common.h"
 #include "kmu.h"
 
@@ -254,7 +254,7 @@ static bool can_sign(const psa_key_attributes_t *key_attr)
  *
  * @return psa_status_t
  */
-static psa_status_t verify_provisioning_state(void)
+static psa_status_t clean_up_unfinished_provisioning(void)
 {
 	uint32_t data;
 	int st = lib_kmu_read_metadata(PROVISIONING_SLOT, &data);
@@ -290,7 +290,7 @@ static psa_status_t verify_provisioning_state(void)
  * @param num_slots
  * @return psa_status_t
  */
-psa_status_t set_provisioning_in_progress(uint32_t slot_id, uint32_t num_slots)
+static psa_status_t set_provisioning_in_progress(uint32_t slot_id, uint32_t num_slots)
 {
 	struct kmu_src_t kmu_desc = {};
 
@@ -312,7 +312,7 @@ psa_status_t set_provisioning_in_progress(uint32_t slot_id, uint32_t num_slots)
  * @param num_slots
  * @return psa_status_t
  */
-psa_status_t end_provisioning(uint32_t slot_id, uint32_t num_slots)
+static psa_status_t end_provisioning(uint32_t slot_id, uint32_t num_slots)
 {
 	if (lib_kmu_revoke_slot(PROVISIONING_SLOT) != LIB_KMU_SUCCESS) {
 		return PSA_ERROR_HARDWARE_FAILURE;
@@ -341,14 +341,15 @@ psa_status_t cracen_kmu_destroy_key(const psa_key_attributes_t *attributes)
 		if (status != PSA_SUCCESS) {
 			return status;
 		}
-		/* Verify will clear related key slots. */
-		return verify_provisioning_state();
+		/* This will revoke the related key slots. */
+		return clean_up_unfinished_provisioning();
 	}
 
 	return PSA_ERROR_DOES_NOT_EXIST;
 }
 
-psa_status_t convert_to_psa_attributes(kmu_metadata *metadata, psa_key_attributes_t *key_attr)
+static psa_status_t convert_to_psa_attributes(kmu_metadata *metadata,
+					      psa_key_attributes_t *key_attr)
 {
 	psa_key_persistence_t key_persistence;
 
@@ -375,7 +376,7 @@ psa_status_t convert_to_psa_attributes(kmu_metadata *metadata, psa_key_attribute
 
 	if (metadata->key_usage_scheme == KMU_METADATA_SCHEME_SEED) {
 		psa_set_key_type(key_attr, PSA_KEY_TYPE_RAW_DATA);
-		psa_set_key_bits(key_attr, 384);
+		psa_set_key_bits(key_attr, PSA_BYTES_TO_BITS(HUK_SIZE_BYTES));
 		return PSA_SUCCESS;
 	}
 
@@ -485,8 +486,6 @@ psa_status_t convert_to_psa_attributes(kmu_metadata *metadata, psa_key_attribute
 			return PSA_ERROR_CORRUPTION_DETECTED;
 		}
 		break;
-	case KMU_METADATA_SCHEME_SEED:
-		return PSA_ERROR_NOT_PERMITTED;
 	}
 
 	return PSA_SUCCESS;
@@ -688,7 +687,7 @@ psa_status_t cracen_kmu_provision(const psa_key_attributes_t *key_attr, int slot
 	uint8_t encrypted_workmem[CRACEN_KMU_SLOT_KEY_SIZE * 4] = {};
 	size_t encrypted_outlen = 0;
 
-	psa_status_t status = verify_provisioning_state();
+	psa_status_t status = clean_up_unfinished_provisioning();
 
 	if (status != PSA_SUCCESS) {
 		return status;
@@ -716,7 +715,7 @@ psa_status_t cracen_kmu_provision(const psa_key_attributes_t *key_attr, int slot
 		break;
 	case KMU_METADATA_SCHEME_SEED:
 		push_address = (uint8_t *)NRF_CRACEN->SEED;
-		if (key_buffer_size != 16 * 3) {
+		if (key_buffer_size != HUK_SIZE_BYTES) {
 			return PSA_ERROR_INVALID_ARGUMENT;
 		}
 		break;
@@ -740,8 +739,8 @@ psa_status_t cracen_kmu_provision(const psa_key_attributes_t *key_attr, int slot
 	}
 
 	/* Verify that required slots are empty */
-	size_t num_slots = (MAX(encrypted_outlen, key_buffer_size) + CRACEN_KMU_SLOT_KEY_SIZE - 1) /
-			   CRACEN_KMU_SLOT_KEY_SIZE;
+	const size_t num_slots =  DIV_ROUND_UP(MAX(encrypted_outlen, key_buffer_size),
+						   CRACEN_KMU_SLOT_KEY_SIZE);
 
 	for (size_t i = 0; i < num_slots; i++) {
 		if (!lib_kmu_is_slot_empty(slot_id + i)) {
@@ -760,7 +759,7 @@ psa_status_t cracen_kmu_provision(const psa_key_attributes_t *key_attr, int slot
 	struct kmu_src_t kmu_desc = {};
 
 	for (size_t i = 0; i < num_slots; i++) {
-		kmu_desc.dest = (uint64_t *)(push_address + (CRACEN_KMU_SLOT_KEY_SIZE * i));
+		kmu_desc.dest = push_address + (CRACEN_KMU_SLOT_KEY_SIZE * i);
 		kmu_desc.metadata = UINT32_MAX;
 		if (i == 0) {
 			memcpy(&kmu_desc.metadata, &metadata, sizeof(metadata));
@@ -775,7 +774,7 @@ psa_status_t cracen_kmu_provision(const psa_key_attributes_t *key_attr, int slot
 			/* We've already verified that this slot empty, so it should not fail. */
 			status = PSA_ERROR_HARDWARE_FAILURE;
 
-			(void)verify_provisioning_state();
+			clean_up_unfinished_provisioning();
 			break;
 		}
 
@@ -856,7 +855,7 @@ psa_status_t cracen_kmu_get_builtin_key(psa_drv_slot_number_t slot_number,
 		return PSA_ERROR_DOES_NOT_EXIST;
 	}
 
-	psa_status_t status = verify_provisioning_state();
+	psa_status_t status = clean_up_unfinished_provisioning();
 
 	if (status != PSA_SUCCESS) {
 		return status;

subsys/nrf_security/src/drivers/cracen/cracenpsa/src/kmu.h

@@ -6,7 +6,7 @@
 #pragma once
 
 #include <stdint.h>
-#include "cracen_psa.h"
+#include <cracen_psa.h>
 
 #define CRACEN_KMU_MAX_KEY_SIZE	 32
 #define CRACEN_KMU_SLOT_KEY_SIZE 16
@@ -27,27 +27,6 @@ typedef struct {
 	uint8_t slot_id;	     /* KMU slot number. */
 } kmu_opaque_key_buffer;
 
-enum kmu_metadata_key_usage_scheme {
-	/**
-	 * These keys can only be pushed to Cracen's protected RAM.
-	 * The keys are not encrypted. Only AES supported.
-	 */
-	KMU_METADATA_SCHEME_PROTECTED,
-	/**
-	 * These keys use 3 key slots. Pushed to the seed register.
-	 */
-	KMU_METADATA_SCHEME_SEED,
-	/**
-	 * These keys are stored in encrypted form. They will be decrypted
-	 * to @ref kmu_push_area for usage.
-	 */
-	KMU_METADATA_SCHEME_ENCRYPTED,
-	/**
-	 * These keys are not encrypted. Pushed to @ref kmu_push_area.
-	 */
-	KMU_METADATA_SCHEME_RAW
-};
-
 extern uint8_t kmu_push_area[64];
 
 /**

subsys/nrf_security/src/drivers/cracen/cracenpsa/src/lib_kmu.c

@@ -26,6 +26,7 @@ void lib_kmu_clear_all_events(void)
 	NRF_KMU_S->EVENTS_PROVISIONED = 0;
 	NRF_KMU_S->EVENTS_PUSHED = 0;
 	NRF_KMU_S->EVENTS_REVOKED = 0;
+	NRF_KMU_S->EVENTS_PUSHBLOCKED = 0;
 }
 
 static int trigger_task_and_wait_for_event_or_error(volatile uint32_t *task,
@@ -70,8 +71,12 @@ int lib_kmu_provision_slot(int slot_id, struct kmu_src_t *kmu_src)
 		return -LIB_KMU_NULL_PNT;
 	}
 
-	/* DEST must be on a 64-bit boundary */
-	__ASSERT(IS_PTR_ALIGNED(kmu_src->dest, uint64_t), "unaligned kmu_src->dest");
+	/* The DEST address must be 64-bit aligned on nrf54l15pdk.
+	 * On nrf54l15dk, the alignment requirement changed to 128 bits.
+	 */
+	__ASSERT(IS_PTR_ALIGNED_BYTES(kmu_src->dest,
+				      (IS_ENABLED(CONFIG_SOC_NRF54L15_ENGA_CPUAPP) ? 8 : 16)),
+		 "DEST misaligned");
 
 	int result = 1;