Look up the SE driver when creating a key
When creating a key with a lifetime that places it in a secure
element, retrieve the appropriate driver table entry.
This commit doesn't yet achieve behavior: so far the code only
retrieves the driver, it doesn't call the driver.
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 5245e61..65e1e2a 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -1291,9 +1291,11 @@
* In case of failure at any step, stop the sequence and call
* psa_fail_key_creation().
*
- * \param attributes Key attributes for the new key.
- * \param handle On success, a handle for the allocated slot.
- * \param p_slot On success, a pointer to the prepared slot.
+ * \param[in] attributes Key attributes for the new key.
+ * \param[out] handle On success, a handle for the allocated slot.
+ * \param[out] p_slot On success, a pointer to the prepared slot.
+ * \param[out] p_drv On any return, the driver for the key, if any.
+ * NULL for a transparent key.
*
* \retval #PSA_SUCCESS
* The key slot is ready to receive key material.
@@ -1303,11 +1305,14 @@
static psa_status_t psa_start_key_creation(
const psa_key_attributes_t *attributes,
psa_key_handle_t *handle,
- psa_key_slot_t **p_slot )
+ psa_key_slot_t **p_slot,
+ const psa_se_drv_table_entry_t **p_drv )
{
psa_status_t status;
psa_key_slot_t *slot;
+ *p_drv = NULL;
+
status = psa_internal_allocate_key_slot( handle, p_slot );
if( status != PSA_SUCCESS )
return( status );
@@ -1317,10 +1322,12 @@
if( status != PSA_SUCCESS )
return( status );
slot->lifetime = attributes->lifetime;
+
if( attributes->lifetime != PSA_KEY_LIFETIME_VOLATILE )
{
status = psa_validate_persistent_key_parameters( attributes->lifetime,
- attributes->id, 1 );
+ attributes->id,
+ p_drv, 1 );
if( status != PSA_SUCCESS )
return( status );
slot->persistent_storage_id = attributes->id;
@@ -1338,17 +1345,22 @@
* See the documentation of psa_start_key_creation() for the intended use
* of this function.
*
- * \param slot Pointer to the slot with key material.
+ * \param[in,out] slot Pointer to the slot with key material.
+ * \param[in] driver The secure element driver for the key,
+ * or NULL for a transparent key.
*
* \retval #PSA_SUCCESS
* The key was successfully created. The handle is now valid.
* \return If this function fails, the key slot is an invalid state.
* You must call psa_fail_key_creation() to wipe and free the slot.
*/
-static psa_status_t psa_finish_key_creation( psa_key_slot_t *slot )
+static psa_status_t psa_finish_key_creation(
+ psa_key_slot_t *slot,
+ const psa_se_drv_table_entry_t *driver )
{
psa_status_t status = PSA_SUCCESS;
(void) slot;
+ (void) driver;
#if defined(MBEDTLS_PSA_CRYPTO_STORAGE_C)
if( slot->lifetime == PSA_KEY_LIFETIME_PERSISTENT )
@@ -1390,12 +1402,25 @@
* See the documentation of psa_start_key_creation() for the intended use
* of this function.
*
- * \param slot Pointer to the slot with key material.
+ * \param[in,out] slot Pointer to the slot with key material.
+ * \param[in] driver The secure element driver for the key,
+ * or NULL for a transparent key.
*/
-static void psa_fail_key_creation( psa_key_slot_t *slot )
+static void psa_fail_key_creation( psa_key_slot_t *slot,
+ const psa_se_drv_table_entry_t *driver )
{
+ (void) driver;
+
if( slot == NULL )
return;
+
+#if defined(MBEDTLS_PSA_CRYPTO_SE_C)
+ /* TOnogrepDO: If the key has already been created in the secure
+ * element, and the failure happened later (when saving metadata
+ * to internal storage), we need to destroy the key in the secure
+ * element. */
+#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
+
psa_wipe_key_slot( slot );
}
@@ -1458,8 +1483,9 @@
{
psa_status_t status;
psa_key_slot_t *slot = NULL;
+ const psa_se_drv_table_entry_t *driver = NULL;
- status = psa_start_key_creation( attributes, handle, &slot );
+ status = psa_start_key_creation( attributes, handle, &slot, &driver );
if( status != PSA_SUCCESS )
goto exit;
@@ -1470,11 +1496,11 @@
if( status != PSA_SUCCESS )
goto exit;
- status = psa_finish_key_creation( slot );
+ status = psa_finish_key_creation( slot, driver );
exit:
if( status != PSA_SUCCESS )
{
- psa_fail_key_creation( slot );
+ psa_fail_key_creation( slot, driver );
*handle = 0;
}
return( status );
@@ -1514,6 +1540,7 @@
psa_key_slot_t *source_slot = NULL;
psa_key_slot_t *target_slot = NULL;
psa_key_attributes_t actual_attributes = *specified_attributes;
+ const psa_se_drv_table_entry_t *driver = NULL;
status = psa_get_key_from_slot( source_handle, &source_slot,
PSA_KEY_USAGE_COPY, 0 );
@@ -1530,7 +1557,7 @@
goto exit;
status = psa_start_key_creation( &actual_attributes,
- target_handle, &target_slot );
+ target_handle, &target_slot, &driver );
if( status != PSA_SUCCESS )
goto exit;
@@ -1538,11 +1565,11 @@
if( status != PSA_SUCCESS )
goto exit;
- status = psa_finish_key_creation( target_slot );
+ status = psa_finish_key_creation( target_slot, driver );
exit:
if( status != PSA_SUCCESS )
{
- psa_fail_key_creation( target_slot );
+ psa_fail_key_creation( target_slot, driver );
*target_handle = 0;
}
return( status );
@@ -4437,7 +4464,8 @@
{
psa_status_t status;
psa_key_slot_t *slot = NULL;
- status = psa_start_key_creation( attributes, handle, &slot );
+ const psa_se_drv_table_entry_t *driver = NULL;
+ status = psa_start_key_creation( attributes, handle, &slot, &driver );
if( status == PSA_SUCCESS )
{
status = psa_generate_derived_key_internal( slot,
@@ -4445,10 +4473,10 @@
operation );
}
if( status == PSA_SUCCESS )
- status = psa_finish_key_creation( slot );
+ status = psa_finish_key_creation( slot, driver );
if( status != PSA_SUCCESS )
{
- psa_fail_key_creation( slot );
+ psa_fail_key_creation( slot, driver );
*handle = 0;
}
return( status );
@@ -5467,7 +5495,8 @@
{
psa_status_t status;
psa_key_slot_t *slot = NULL;
- status = psa_start_key_creation( attributes, handle, &slot );
+ const psa_se_drv_table_entry_t *driver = NULL;
+ status = psa_start_key_creation( attributes, handle, &slot, &driver );
if( status == PSA_SUCCESS )
{
status = psa_generate_key_internal(
@@ -5475,10 +5504,10 @@
attributes->domain_parameters, attributes->domain_parameters_size );
}
if( status == PSA_SUCCESS )
- status = psa_finish_key_creation( slot );
+ status = psa_finish_key_creation( slot, driver );
if( status != PSA_SUCCESS )
{
- psa_fail_key_creation( slot );
+ psa_fail_key_creation( slot, driver );
*handle = 0;
}
return( status );
diff --git a/library/psa_crypto_slot_management.c b/library/psa_crypto_slot_management.c
index 900aa41..eb24b6b 100644
--- a/library/psa_crypto_slot_management.c
+++ b/library/psa_crypto_slot_management.c
@@ -168,8 +168,20 @@
psa_status_t psa_validate_persistent_key_parameters(
psa_key_lifetime_t lifetime,
psa_key_file_id_t id,
+ const psa_se_drv_table_entry_t **p_drv,
int creating )
{
+ if( p_drv != NULL )
+ *p_drv = NULL;
+#if defined(MBEDTLS_PSA_CRYPTO_SE_C)
+ if( psa_key_lifetime_is_external( lifetime ) )
+ {
+ *p_drv = psa_get_se_driver_entry( lifetime );
+ if( *p_drv == NULL )
+ return( PSA_ERROR_INVALID_ARGUMENT );
+ }
+ else
+#endif /* MBEDTLS_PSA_CRYPTO_SE_C */
if( lifetime != PSA_KEY_LIFETIME_PERSISTENT )
return( PSA_ERROR_INVALID_ARGUMENT );
@@ -194,7 +206,7 @@
*handle = 0;
status = psa_validate_persistent_key_parameters(
- PSA_KEY_LIFETIME_PERSISTENT, id, 0 );
+ PSA_KEY_LIFETIME_PERSISTENT, id, NULL, 0 );
if( status != PSA_SUCCESS )
return( status );
diff --git a/library/psa_crypto_slot_management.h b/library/psa_crypto_slot_management.h
index 5c1bde1..8111c4a 100644
--- a/library/psa_crypto_slot_management.h
+++ b/library/psa_crypto_slot_management.h
@@ -22,6 +22,9 @@
#ifndef PSA_CRYPTO_SLOT_MANAGEMENT_H
#define PSA_CRYPTO_SLOT_MANAGEMENT_H
+#include "psa/crypto.h"
+#include "psa_crypto_se.h"
+
/* Number of key slots (plus one because 0 is not used).
* The value is a compile-time constant for now, for simplicity. */
#define PSA_KEY_SLOT_COUNT 32
@@ -71,6 +74,24 @@
psa_status_t psa_internal_allocate_key_slot( psa_key_handle_t *handle,
psa_key_slot_t **p_slot );
+/** Test whether a lifetime designates a key in an external cryptoprocessor.
+ *
+ * \param lifetime The lifetime to test.
+ *
+ * \retval 1
+ * The lifetime designates an external key. There should be a
+ * registered driver for this lifetime, otherwise the key cannot
+ * be created or manipulated.
+ * \retval 0
+ * The lifetime designates a key that is volatile or in internal
+ * storage.
+ */
+static inline int psa_key_lifetime_is_external( psa_key_lifetime_t lifetime )
+{
+ return( lifetime != PSA_KEY_LIFETIME_VOLATILE &&
+ lifetime != PSA_KEY_LIFETIME_PERSISTENT );
+}
+
/** Test whether the given parameters are acceptable for a persistent key.
*
* This function does not access the storage in any way. It only tests
@@ -78,8 +99,16 @@
* It does not test whether the a file by the given id exists or could be
* created.
*
+ * If the key is in external storage, this function returns the corresponding
+ * driver.
+ *
* \param lifetime The lifetime to test.
* \param id The key id to test.
+ * \param[out] p_drv On output, if \p lifetime designates a key
+ * in an external processor, \c *p_drv is a pointer
+ * to the driver table entry fot this lifetime.
+ * If \p lifetime designates a transparent key,
+ * \c *p_drv is \c NULL.
* \param creating 0 if attempting to open an existing key.
* Nonzero if attempting to create a key.
*
@@ -93,6 +122,7 @@
psa_status_t psa_validate_persistent_key_parameters(
psa_key_lifetime_t lifetime,
psa_key_file_id_t id,
+ const psa_se_drv_table_entry_t **p_drv,
int creating );