Add mbedtls_psa_crypto_init_subsystem()
Internal only for now, but can be made external with some more
work. Break up psa_crypto_init into chunks to prevent deadlocks when
initialising RNG, likewise break up mbedtls_crypto_free() to stop having
to hold more than one mutex at a time.
Signed-off-by: Paul Elliott <paul.elliott@arm.com>
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 63fd05c..8884267 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -93,10 +93,25 @@
#define RNG_INITIALIZED 1
#define RNG_SEEDED 2
+typedef enum {
+ PSA_CRYPTO_SUBSYSTEM_DRIVER_WRAPPERS = 0,
+ PSA_CRYPTO_SUBSYSTEM_KEY_SLOTS,
+ PSA_CRYPTO_SUBSYSTEM_RNG,
+ PSA_CRYPTO_SUBSYSTEM_TRANSACTION,
+} mbedtls_psa_crypto_subsystem;
+
+#define PSA_CRYPTO_SUBSYSTEM_DRIVER_WRAPPERS_INITIALIZED 0x01
+#define PSA_CRYPTO_SUBSYSTEM_KEY_SLOTS_INITIALIZED 0x02
+#define PSA_CRYPTO_SUBSYSTEM_TRANSACTION_INITIALIZED 0x04
+
+#define PSA_CRYPTO_SUBSYSTEM_ALL_INITIALISED ( \
+ PSA_CRYPTO_SUBSYSTEM_DRIVER_WRAPPERS_INITIALIZED | \
+ PSA_CRYPTO_SUBSYSTEM_KEY_SLOTS_INITIALIZED | \
+ PSA_CRYPTO_SUBSYSTEM_TRANSACTION_INITIALIZED)
+
typedef struct {
uint8_t initialized;
uint8_t rng_state;
- uint8_t drivers_initialized;
mbedtls_psa_random_context_t rng;
} psa_global_data_t;
@@ -107,10 +122,21 @@
uint8_t initialized;
#if defined(MBEDTLS_THREADING_C)
+ mbedtls_mutex_lock(&mbedtls_threading_psa_rngdata_mutex);
+#endif /* defined(MBEDTLS_THREADING_C) */
+
+ initialized = global_data.rng_state == RNG_SEEDED;
+
+#if defined(MBEDTLS_THREADING_C)
+ mbedtls_mutex_unlock(&mbedtls_threading_psa_rngdata_mutex);
+#endif /* defined(MBEDTLS_THREADING_C) */
+
+#if defined(MBEDTLS_THREADING_C)
mbedtls_mutex_lock(&mbedtls_threading_psa_globaldata_mutex);
#endif /* defined(MBEDTLS_THREADING_C) */
- initialized = global_data.initialized;
+ initialized =
+ (initialized && (global_data.initialized == PSA_CRYPTO_SUBSYSTEM_ALL_INITIALISED));
#if defined(MBEDTLS_THREADING_C)
mbedtls_mutex_unlock(&mbedtls_threading_psa_globaldata_mutex);
@@ -127,7 +153,7 @@
mbedtls_mutex_lock(&mbedtls_threading_psa_globaldata_mutex);
#endif /* defined(MBEDTLS_THREADING_C) */
- initialized = global_data.drivers_initialized;
+ initialized = (global_data.initialized & PSA_CRYPTO_SUBSYSTEM_DRIVER_WRAPPERS_INITIALIZED) != 0;
#if defined(MBEDTLS_THREADING_C)
mbedtls_mutex_unlock(&mbedtls_threading_psa_globaldata_mutex);
@@ -7490,29 +7516,53 @@
void mbedtls_psa_crypto_free(void)
{
- /* Need to hold the mutex here to prevent this going ahead before
- * psa_crypto_init() has completed, and to ensure integrity of
- * global_data. */
+
#if defined(MBEDTLS_THREADING_C)
mbedtls_mutex_lock(&mbedtls_threading_psa_globaldata_mutex);
#endif /* defined(MBEDTLS_THREADING_C) */
- psa_wipe_all_key_slots();
- if (global_data.rng_state != RNG_NOT_INITIALIZED) {
- mbedtls_psa_random_free(&global_data.rng);
+ /* Nothing to do to free transaction. */
+ if (global_data.initialized & PSA_CRYPTO_SUBSYSTEM_TRANSACTION_INITIALIZED) {
+ global_data.initialized &= ~PSA_CRYPTO_SUBSYSTEM_TRANSACTION_INITIALIZED;
}
- /* Wipe all remaining data, including configuration.
- * In particular, this sets all state indicator to the value
- * indicating "uninitialized". */
- mbedtls_platform_zeroize(&global_data, sizeof(global_data));
+ if (global_data.initialized & PSA_CRYPTO_SUBSYSTEM_KEY_SLOTS_INITIALIZED) {
+ psa_wipe_all_key_slots();
+ global_data.initialized &= ~PSA_CRYPTO_SUBSYSTEM_KEY_SLOTS_INITIALIZED;
+ }
#if defined(MBEDTLS_THREADING_C)
mbedtls_mutex_unlock(&mbedtls_threading_psa_globaldata_mutex);
#endif /* defined(MBEDTLS_THREADING_C) */
+#if defined(MBEDTLS_THREADING_C)
+ mbedtls_mutex_lock(&mbedtls_threading_psa_rngdata_mutex);
+#endif /* defined(MBEDTLS_THREADING_C) */
+
+ if (global_data.rng_state != RNG_NOT_INITIALIZED) {
+ mbedtls_psa_random_free(&global_data.rng);
+ }
+ global_data.rng_state = RNG_NOT_INITIALIZED;
+ mbedtls_platform_zeroize(&global_data.rng, sizeof(global_data.rng));
+
+#if defined(MBEDTLS_THREADING_C)
+ mbedtls_mutex_unlock(&mbedtls_threading_psa_rngdata_mutex);
+#endif /* defined(MBEDTLS_THREADING_C) */
+
+#if defined(MBEDTLS_THREADING_C)
+ mbedtls_mutex_lock(&mbedtls_threading_psa_globaldata_mutex);
+#endif /* defined(MBEDTLS_THREADING_C) */
+
/* Terminate drivers */
- psa_driver_wrapper_free();
+ if (global_data.initialized & PSA_CRYPTO_SUBSYSTEM_DRIVER_WRAPPERS_INITIALIZED) {
+ psa_driver_wrapper_free();
+ global_data.initialized &= ~PSA_CRYPTO_SUBSYSTEM_DRIVER_WRAPPERS_INITIALIZED;
+ }
+
+#if defined(MBEDTLS_THREADING_C)
+ mbedtls_mutex_unlock(&mbedtls_threading_psa_globaldata_mutex);
+#endif /* defined(MBEDTLS_THREADING_C) */
+
}
#if defined(PSA_CRYPTO_STORAGE_HAS_TRANSACTIONS)
@@ -7540,74 +7590,172 @@
}
#endif /* PSA_CRYPTO_STORAGE_HAS_TRANSACTIONS */
+static psa_status_t mbedtls_psa_crypto_init_subsystem(mbedtls_psa_crypto_subsystem subsystem)
+{
+ psa_status_t status = PSA_SUCCESS;
+ uint8_t driver_wrappers_initialized = 0;
+
+ switch (subsystem) {
+ case PSA_CRYPTO_SUBSYSTEM_DRIVER_WRAPPERS:
+
+#if defined(MBEDTLS_THREADING_C)
+ PSA_THREADING_CHK_GOTO_EXIT(mbedtls_mutex_lock(&mbedtls_threading_psa_globaldata_mutex));
+#endif /* defined(MBEDTLS_THREADING_C) */
+
+ if (!(global_data.initialized & PSA_CRYPTO_SUBSYSTEM_DRIVER_WRAPPERS_INITIALIZED)) {
+ /* Init drivers */
+ status = psa_driver_wrapper_init();
+
+ /* Drivers need shutdown regardless of startup errors. */
+ global_data.initialized |= PSA_CRYPTO_SUBSYSTEM_DRIVER_WRAPPERS_INITIALIZED;
+
+
+ }
+#if defined(MBEDTLS_THREADING_C)
+ PSA_THREADING_CHK_GOTO_EXIT(mbedtls_mutex_unlock(
+ &mbedtls_threading_psa_globaldata_mutex));
+#endif /* defined(MBEDTLS_THREADING_C) */
+
+ break;
+
+ case PSA_CRYPTO_SUBSYSTEM_KEY_SLOTS:
+
+#if defined(MBEDTLS_THREADING_C)
+ PSA_THREADING_CHK_GOTO_EXIT(mbedtls_mutex_lock(&mbedtls_threading_psa_globaldata_mutex));
+#endif /* defined(MBEDTLS_THREADING_C) */
+
+ if (!(global_data.initialized & PSA_CRYPTO_SUBSYSTEM_KEY_SLOTS_INITIALIZED)) {
+ status = psa_initialize_key_slots();
+
+ /* Need to wipe keys even if initialization fails. */
+ global_data.initialized |= PSA_CRYPTO_SUBSYSTEM_KEY_SLOTS_INITIALIZED;
+
+ }
+#if defined(MBEDTLS_THREADING_C)
+ PSA_THREADING_CHK_GOTO_EXIT(mbedtls_mutex_unlock(
+ &mbedtls_threading_psa_globaldata_mutex));
+#endif /* defined(MBEDTLS_THREADING_C) */
+
+ break;
+
+ case PSA_CRYPTO_SUBSYSTEM_RNG:
+
+#if defined(MBEDTLS_THREADING_C)
+ PSA_THREADING_CHK_GOTO_EXIT(mbedtls_mutex_lock(&mbedtls_threading_psa_globaldata_mutex));
+#endif /* defined(MBEDTLS_THREADING_C) */
+
+ driver_wrappers_initialized =
+ (global_data.initialized & PSA_CRYPTO_SUBSYSTEM_DRIVER_WRAPPERS_INITIALIZED);
+
+#if defined(MBEDTLS_THREADING_C)
+ PSA_THREADING_CHK_GOTO_EXIT(mbedtls_mutex_unlock(
+ &mbedtls_threading_psa_globaldata_mutex));
+#endif /* defined(MBEDTLS_THREADING_C) */
+
+ /* Need to use separate mutex here, as initialisation can require
+ * testing of init flags, which requires locking the global data
+ * mutex. */
+#if defined(MBEDTLS_THREADING_C)
+ PSA_THREADING_CHK_GOTO_EXIT(mbedtls_mutex_lock(&mbedtls_threading_psa_rngdata_mutex));
+#endif /* defined(MBEDTLS_THREADING_C) */
+
+ /* Initialize and seed the random generator. */
+ if (global_data.rng_state == RNG_NOT_INITIALIZED && driver_wrappers_initialized) {
+ mbedtls_psa_random_init(&global_data.rng);
+ global_data.rng_state = RNG_INITIALIZED;
+
+ status = mbedtls_psa_random_seed(&global_data.rng);
+ if (status == PSA_SUCCESS) {
+ global_data.rng_state = RNG_SEEDED;
+ }
+ }
+
+#if defined(MBEDTLS_THREADING_C)
+ PSA_THREADING_CHK_GOTO_EXIT(mbedtls_mutex_unlock(
+ &mbedtls_threading_psa_rngdata_mutex));
+#endif /* defined(MBEDTLS_THREADING_C) */
+
+
+ break;
+
+ case PSA_CRYPTO_SUBSYSTEM_TRANSACTION:
+
+#if defined(MBEDTLS_THREADING_C)
+ PSA_THREADING_CHK_GOTO_EXIT(mbedtls_mutex_lock(&mbedtls_threading_psa_globaldata_mutex));
+#endif /* defined(MBEDTLS_THREADING_C) */
+
+ if (!(global_data.initialized & PSA_CRYPTO_SUBSYSTEM_TRANSACTION_INITIALIZED)) {
+#if defined(PSA_CRYPTO_STORAGE_HAS_TRANSACTIONS)
+ status = psa_crypto_load_transaction();
+ if (status == PSA_SUCCESS) {
+ status = psa_crypto_recover_transaction(&psa_crypto_transaction);
+ if (status == PSA_SUCCESS) {
+ global_data.initialized |= PSA_CRYPTO_SUBSYSTEM_TRANSACTION_INITIALIZED;
+ }
+ status = psa_crypto_stop_transaction();
+ } else if (status == PSA_ERROR_DOES_NOT_EXIST) {
+ /* There's no transaction to complete. It's all good. */
+ global_data.initialized |= PSA_CRYPTO_SUBSYSTEM_TRANSACTION_INITIALIZED;
+ status = PSA_SUCCESS;
+ }
+#else /* defined(PSA_CRYPTO_STORAGE_HAS_TRANSACTIONS) */
+ global_data.initialized |= PSA_CRYPTO_SUBSYSTEM_TRANSACTION_INITIALIZED;
+ status = PSA_SUCCESS;
+#endif /* defined(PSA_CRYPTO_STORAGE_HAS_TRANSACTIONS) */
+ }
+
+#if defined(MBEDTLS_THREADING_C)
+ PSA_THREADING_CHK_GOTO_EXIT(mbedtls_mutex_unlock(
+ &mbedtls_threading_psa_globaldata_mutex));
+#endif /* defined(MBEDTLS_THREADING_C) */
+
+ break;
+
+ default:
+ status = PSA_ERROR_CORRUPTION_DETECTED;
+ }
+
+ /* Exit label only required when using threading macros. */
+#if defined(MBEDTLS_THREADING_C)
+exit:
+#endif /* defined(MBEDTLS_THREADING_C) */
+
+ return status;
+}
+
psa_status_t psa_crypto_init(void)
{
psa_status_t status;
- /* Need to hold the mutex for the entire function to prevent incomplete
- * initialisation before someone calls psa_crypto_free() or calls this
- * function again before we set global_data.initialised to 1. */
- #if defined(MBEDTLS_THREADING_C)
- mbedtls_mutex_lock(&mbedtls_threading_psa_globaldata_mutex);
-#endif /* defined(MBEDTLS_THREADING_C) */
-
- /* We cannot use psa_get_initialized() here as we already hold the mutex. */
- if (global_data.initialized == 1) {
-#if defined(MBEDTLS_THREADING_C)
- mbedtls_mutex_unlock(&mbedtls_threading_psa_globaldata_mutex);
-#endif /* defined(MBEDTLS_THREADING_C) */
-
- /* Double initialization is explicitly allowed. */
+ /* Double initialization is explicitly allowed. Early out if everything is
+ * done. */
+ if (psa_get_initialized()) {
return PSA_SUCCESS;
}
- /* Init drivers */
- status = psa_driver_wrapper_init();
- if (status != PSA_SUCCESS) {
- goto exit;
- }
- global_data.drivers_initialized = 1;
-
- status = psa_initialize_key_slots();
+ status = mbedtls_psa_crypto_init_subsystem(PSA_CRYPTO_SUBSYSTEM_DRIVER_WRAPPERS);
if (status != PSA_SUCCESS) {
goto exit;
}
- /* Initialize and seed the random generator. */
- mbedtls_psa_random_init(&global_data.rng);
- global_data.rng_state = RNG_INITIALIZED;
- status = mbedtls_psa_random_seed(&global_data.rng);
+ status = mbedtls_psa_crypto_init_subsystem(PSA_CRYPTO_SUBSYSTEM_KEY_SLOTS);
if (status != PSA_SUCCESS) {
goto exit;
}
- global_data.rng_state = RNG_SEEDED;
-#if defined(PSA_CRYPTO_STORAGE_HAS_TRANSACTIONS)
- status = psa_crypto_load_transaction();
- if (status == PSA_SUCCESS) {
- status = psa_crypto_recover_transaction(&psa_crypto_transaction);
- if (status != PSA_SUCCESS) {
- goto exit;
- }
- status = psa_crypto_stop_transaction();
- } else if (status == PSA_ERROR_DOES_NOT_EXIST) {
- /* There's no transaction to complete. It's all good. */
- status = PSA_SUCCESS;
+ status = mbedtls_psa_crypto_init_subsystem(PSA_CRYPTO_SUBSYSTEM_RNG);
+ if (status != PSA_SUCCESS) {
+ goto exit;
}
-#endif /* PSA_CRYPTO_STORAGE_HAS_TRANSACTIONS */
- /* All done. */
- global_data.initialized = 1;
+ status = mbedtls_psa_crypto_init_subsystem(PSA_CRYPTO_SUBSYSTEM_TRANSACTION);
exit:
-#if defined(MBEDTLS_THREADING_C)
- mbedtls_mutex_unlock(&mbedtls_threading_psa_globaldata_mutex);
-#endif /* defined(MBEDTLS_THREADING_C) */
-
if (status != PSA_SUCCESS) {
mbedtls_psa_crypto_free();
}
+
return status;
}