From 5b229a06f4501147f5260a05c57b93e80ec0f2ca Mon Sep 17 00:00:00 2001 From: Gilles Peskine Date: Tue, 19 Feb 2019 13:24:37 +0100 Subject: [PATCH] Support encoding an owner in key file IDs Differentiate between _key identifiers_, which are always `uint32_t`, and _key file identifiers_, which are platform-dependent. Normally, the two are the same. In `psa/crypto_platform.h`, define `psa_app_key_id_t` (which is always 32 bits, the standard key identifier type) and `psa_key_file_id_t` (which will be different in some service builds). A subsequent commit will introduce a platform where the two are different. It would make sense for the function declarations in `psa/crypto.h` to use `psa_key_file_id_t`. However this file is currently part of the PSA Crypto API specification, so it must stick to the standard type `psa_key_id_t`. Hence, as long as the specification and Mbed Crypto are not separate, use the implementation-specific file `psa/crypto_platform.h` to define `psa_key_id_t` as `psa_key_file_id_t`. In the library, systematically use `psa_key_file_id_t`. perl -i -pe 's/psa_key_id_t/psa_key_file_id_t/g' library/*.[hc] --- include/psa/crypto_platform.h | 23 +++++++++++++++++++++++ library/psa_crypto_core.h | 2 +- library/psa_crypto_slot_management.c | 15 ++++++++------- library/psa_crypto_storage.c | 4 ++-- library/psa_crypto_storage.h | 6 +++--- library/psa_crypto_storage_backend.h | 8 ++++---- library/psa_crypto_storage_file.c | 12 ++++++------ library/psa_crypto_storage_its.c | 12 ++++++------ 8 files changed, 53 insertions(+), 29 deletions(-) diff --git a/include/psa/crypto_platform.h b/include/psa/crypto_platform.h index 50ca546fb6..0f3ede8911 100644 --- a/include/psa/crypto_platform.h +++ b/include/psa/crypto_platform.h @@ -49,4 +49,27 @@ /* Integral type representing a key handle. */ typedef uint16_t psa_key_handle_t; +/* This implementation distinguishes *application key identifiers*, which + * are the key identifiers specified by the application, from + * *key file identifiers*, which are the key identifiers that the library + * sees internally. The two types can be different if there is a remote + * call layer between the application and the library which supports + * multiple client applications that do not have access to each others' + * keys. The point of having different types is that the key file + * identifier may encode not only the key identifier specified by the + * application, but also the the identity of the application. + * + * Note that this is an internal concept of the library and the remote + * call layer. The application itself never sees anything other than + * #psa_app_key_id_t with its standard definition. + */ + +/* The application key identifier is always what the application sees as + * #psa_key_id_t. */ +typedef uint32_t psa_app_key_id_t; + +/* By default, a key file identifier is just the application key identifier. */ +typedef psa_app_key_id_t psa_key_file_id_t; +#define PSA_KEY_FILE_GET_KEY_ID( id ) ( id ) + #endif /* PSA_CRYPTO_PLATFORM_H */ diff --git a/library/psa_crypto_core.h b/library/psa_crypto_core.h index c289681973..0f75624597 100644 --- a/library/psa_crypto_core.h +++ b/library/psa_crypto_core.h @@ -41,7 +41,7 @@ typedef struct psa_key_type_t type; psa_key_policy_t policy; psa_key_lifetime_t lifetime; - psa_key_id_t persistent_storage_id; + psa_key_file_id_t persistent_storage_id; unsigned allocated : 1; union { diff --git a/library/psa_crypto_slot_management.c b/library/psa_crypto_slot_management.c index a9458b04ff..227fb5f110 100644 --- a/library/psa_crypto_slot_management.c +++ b/library/psa_crypto_slot_management.c @@ -189,12 +189,13 @@ exit: * past released version must remain valid, unless a migration path * is provided. * - * \param key_id The key identifier to check. + * \param file_id The key identifier to check. * - * \return 1 if \p key_id is acceptable, otherwise 0. + * \return 1 if \p file_id is acceptable, otherwise 0. */ -static int psa_is_key_id_valid( psa_key_id_t key_id ) +static int psa_is_key_id_valid( psa_key_file_id_t file_id ) { + psa_app_key_id_t key_id = PSA_KEY_FILE_GET_KEY_ID( file_id ); /* Reject id=0 because by general library conventions, 0 is an invalid * value wherever possible. */ if( key_id == 0 ) @@ -226,7 +227,7 @@ static int psa_is_key_id_valid( psa_key_id_t key_id ) * \retval #PSA_ERROR_STORAGE_FAILURE */ static psa_status_t psa_internal_make_key_persistent( psa_key_handle_t handle, - psa_key_id_t id ) + psa_key_file_id_t id ) { #if defined(MBEDTLS_PSA_CRYPTO_STORAGE_C) psa_key_slot_t *slot; @@ -253,7 +254,7 @@ static psa_status_t psa_internal_make_key_persistent( psa_key_handle_t handle, } static psa_status_t persistent_key_setup( psa_key_lifetime_t lifetime, - psa_key_id_t id, + psa_key_file_id_t id, psa_key_handle_t *handle, psa_status_t wanted_load_status ) { @@ -278,14 +279,14 @@ static psa_status_t persistent_key_setup( psa_key_lifetime_t lifetime, } psa_status_t psa_open_key( psa_key_lifetime_t lifetime, - psa_key_id_t id, + psa_key_file_id_t id, psa_key_handle_t *handle ) { return( persistent_key_setup( lifetime, id, handle, PSA_SUCCESS ) ); } psa_status_t psa_create_key( psa_key_lifetime_t lifetime, - psa_key_id_t id, + psa_key_file_id_t id, psa_key_handle_t *handle ) { psa_status_t status; diff --git a/library/psa_crypto_storage.c b/library/psa_crypto_storage.c index b4e4076e1a..42bd938de1 100644 --- a/library/psa_crypto_storage.c +++ b/library/psa_crypto_storage.c @@ -148,7 +148,7 @@ psa_status_t psa_parse_key_data_from_storage( const uint8_t *storage_data, return( PSA_SUCCESS ); } -psa_status_t psa_save_persistent_key( const psa_key_id_t key, +psa_status_t psa_save_persistent_key( const psa_key_file_id_t key, const psa_key_type_t type, const psa_key_policy_t *policy, const uint8_t *data, @@ -186,7 +186,7 @@ void psa_free_persistent_key_data( uint8_t *key_data, size_t key_data_length ) mbedtls_free( key_data ); } -psa_status_t psa_load_persistent_key( psa_key_id_t key, +psa_status_t psa_load_persistent_key( psa_key_file_id_t key, psa_key_type_t *type, psa_key_policy_t *policy, uint8_t **data, diff --git a/library/psa_crypto_storage.h b/library/psa_crypto_storage.h index 74f9e230db..7e5aae9f98 100644 --- a/library/psa_crypto_storage.h +++ b/library/psa_crypto_storage.h @@ -86,7 +86,7 @@ extern "C" { * \retval PSA_ERROR_STORAGE_FAILURE * \retval PSA_ERROR_ALREADY_EXISTS */ -psa_status_t psa_save_persistent_key( const psa_key_id_t key, +psa_status_t psa_save_persistent_key( const psa_key_file_id_t key, const psa_key_type_t type, const psa_key_policy_t *policy, const uint8_t *data, @@ -117,7 +117,7 @@ psa_status_t psa_save_persistent_key( const psa_key_id_t key, * \retval PSA_ERROR_STORAGE_FAILURE * \retval PSA_ERROR_DOES_NOT_EXIST */ -psa_status_t psa_load_persistent_key( psa_key_id_t key, +psa_status_t psa_load_persistent_key( psa_key_file_id_t key, psa_key_type_t *type, psa_key_policy_t *policy, uint8_t **data, @@ -134,7 +134,7 @@ psa_status_t psa_load_persistent_key( psa_key_id_t key, * or the key did not exist. * \retval PSA_ERROR_STORAGE_FAILURE */ -psa_status_t psa_destroy_persistent_key( const psa_key_id_t key ); +psa_status_t psa_destroy_persistent_key( const psa_key_file_id_t key ); /** * \brief Free the temporary buffer allocated by psa_load_persistent_key(). diff --git a/library/psa_crypto_storage_backend.h b/library/psa_crypto_storage_backend.h index 83bd2f359d..dd534d2ff1 100644 --- a/library/psa_crypto_storage_backend.h +++ b/library/psa_crypto_storage_backend.h @@ -56,7 +56,7 @@ extern "C" { * \retval PSA_ERROR_STORAGE_FAILURE * \retval PSA_ERROR_DOES_NOT_EXIST */ -psa_status_t psa_crypto_storage_load( const psa_key_id_t key, uint8_t *data, +psa_status_t psa_crypto_storage_load( const psa_key_file_id_t key, uint8_t *data, size_t data_size ); /** @@ -75,7 +75,7 @@ psa_status_t psa_crypto_storage_load( const psa_key_id_t key, uint8_t *data, * \retval PSA_ERROR_STORAGE_FAILURE * \retval PSA_ERROR_ALREADY_EXISTS */ -psa_status_t psa_crypto_storage_store( const psa_key_id_t key, +psa_status_t psa_crypto_storage_store( const psa_key_file_id_t key, const uint8_t *data, size_t data_length ); @@ -92,7 +92,7 @@ psa_status_t psa_crypto_storage_store( const psa_key_id_t key, * \retval 1 * Persistent data present for slot number */ -int psa_is_key_present_in_storage( const psa_key_id_t key ); +int psa_is_key_present_in_storage( const psa_key_file_id_t key ); /** * \brief Get data length for given key slot number. @@ -104,7 +104,7 @@ int psa_is_key_present_in_storage( const psa_key_id_t key ); * \retval PSA_SUCCESS * \retval PSA_ERROR_STORAGE_FAILURE */ -psa_status_t psa_crypto_storage_get_data_length( const psa_key_id_t key, +psa_status_t psa_crypto_storage_get_data_length( const psa_key_file_id_t key, size_t *data_length ); diff --git a/library/psa_crypto_storage_file.c b/library/psa_crypto_storage_file.c index c7ff1be013..c4a534fe36 100644 --- a/library/psa_crypto_storage_file.c +++ b/library/psa_crypto_storage_file.c @@ -49,7 +49,7 @@ enum { MAX_LOCATION_LEN = sizeof(CRYPTO_STORAGE_FILE_LOCATION) + 40 }; -static void key_id_to_location( const psa_key_id_t key, +static void key_id_to_location( const psa_key_file_id_t key, char *location, size_t location_size ) { @@ -58,7 +58,7 @@ static void key_id_to_location( const psa_key_id_t key, (unsigned long) key ); } -psa_status_t psa_crypto_storage_load( const psa_key_id_t key, uint8_t *data, +psa_status_t psa_crypto_storage_load( const psa_key_file_id_t key, uint8_t *data, size_t data_size ) { psa_status_t status = PSA_SUCCESS; @@ -83,7 +83,7 @@ exit: return( status ); } -int psa_is_key_present_in_storage( const psa_key_id_t key ) +int psa_is_key_present_in_storage( const psa_key_file_id_t key ) { char slot_location[MAX_LOCATION_LEN]; FILE *file; @@ -101,7 +101,7 @@ int psa_is_key_present_in_storage( const psa_key_id_t key ) return( 1 ); } -psa_status_t psa_crypto_storage_store( const psa_key_id_t key, +psa_status_t psa_crypto_storage_store( const psa_key_file_id_t key, const uint8_t *data, size_t data_length ) { @@ -156,7 +156,7 @@ exit: return( status ); } -psa_status_t psa_destroy_persistent_key( const psa_key_id_t key ) +psa_status_t psa_destroy_persistent_key( const psa_key_file_id_t key ) { FILE *file; char slot_location[MAX_LOCATION_LEN]; @@ -175,7 +175,7 @@ psa_status_t psa_destroy_persistent_key( const psa_key_id_t key ) return( PSA_SUCCESS ); } -psa_status_t psa_crypto_storage_get_data_length( const psa_key_id_t key, +psa_status_t psa_crypto_storage_get_data_length( const psa_key_file_id_t key, size_t *data_length ) { psa_status_t status = PSA_SUCCESS; diff --git a/library/psa_crypto_storage_its.c b/library/psa_crypto_storage_its.c index bb0d0cdf19..a60a8f3abc 100644 --- a/library/psa_crypto_storage_its.c +++ b/library/psa_crypto_storage_its.c @@ -36,12 +36,12 @@ #include "mbedtls/platform.h" #endif -static psa_storage_uid_t psa_its_identifier_of_slot( psa_key_id_t key ) +static psa_storage_uid_t psa_its_identifier_of_slot( psa_key_file_id_t key ) { return( key ); } -psa_status_t psa_crypto_storage_load( const psa_key_id_t key, uint8_t *data, +psa_status_t psa_crypto_storage_load( const psa_key_file_id_t key, uint8_t *data, size_t data_size ) { psa_status_t status; @@ -57,7 +57,7 @@ psa_status_t psa_crypto_storage_load( const psa_key_id_t key, uint8_t *data, return( status ); } -int psa_is_key_present_in_storage( const psa_key_id_t key ) +int psa_is_key_present_in_storage( const psa_key_file_id_t key ) { psa_status_t ret; psa_storage_uid_t data_identifier = psa_its_identifier_of_slot( key ); @@ -70,7 +70,7 @@ int psa_is_key_present_in_storage( const psa_key_id_t key ) return( 1 ); } -psa_status_t psa_crypto_storage_store( const psa_key_id_t key, +psa_status_t psa_crypto_storage_store( const psa_key_file_id_t key, const uint8_t *data, size_t data_length ) { @@ -105,7 +105,7 @@ exit: return( status ); } -psa_status_t psa_destroy_persistent_key( const psa_key_id_t key ) +psa_status_t psa_destroy_persistent_key( const psa_key_file_id_t key ) { psa_status_t ret; psa_storage_uid_t data_identifier = psa_its_identifier_of_slot( key ); @@ -125,7 +125,7 @@ psa_status_t psa_destroy_persistent_key( const psa_key_id_t key ) return( PSA_SUCCESS ); } -psa_status_t psa_crypto_storage_get_data_length( const psa_key_id_t key, +psa_status_t psa_crypto_storage_get_data_length( const psa_key_file_id_t key, size_t *data_length ) { psa_status_t status;