Remove domain parameters

ChangeLog.d/domain_parameters.txt

@@ -0,0 +1,9 @@
+New deprecations
+   * In the PSA API, domain parameters are no longer used for anything.
+     They are deprecated and will be removed in a future version of the
+     library.
+
+Removals
+   * In the PSA API, the experimental way to encode the public exponent of
+     an RSA key as a domain parameter is no longer supported. Use
+     psa_generate_key_ext() instead.

include/psa/crypto.h

@@ -4144,7 +4144,7 @@ psa_status_t psa_generate_key(const psa_key_attributes_t *attributes,
  *                          When this is #PSA_KEY_PRODUCTION_PARAMETERS_INIT
  *                          with \p params_data_length = 0,
  *                          this function is equivalent to
- *                          psa_key_generation_output_key().
+ *                          psa_generate_key().
  * \param params_data_length
  *                          Length of `params->data` in bytes.
  * \param[out] key          On success, an identifier for the newly created

include/psa/crypto_compat.h

@@ -146,6 +146,83 @@ psa_status_t psa_open_key(mbedtls_svc_key_id_t key,
  */
 psa_status_t psa_close_key(psa_key_handle_t handle);
 
+/** \addtogroup attributes
+ * @{
+ */
+
+#if !defined(MBEDTLS_DEPRECATED_REMOVED)
+/** Custom Diffie-Hellman group.
+ *
+ * Mbed TLS does not support custom DH groups.
+ *
+ * \deprecated This value is not useful, so this macro will be removed in
+ *             a future version of the library.
+ */
+#define PSA_DH_FAMILY_CUSTOM                                            \
+    ((psa_dh_family_t) MBEDTLS_DEPRECATED_NUMERIC_CONSTANT(0x7e))
+
+/**
+ * \brief Set domain parameters for a key.
+ *
+ * \deprecated  Mbed TLS no longer supports any domain parameters.
+ *              This function only does the equivalent of
+ *              psa_set_key_type() and will be removed in a future version
+ *              of the library.
+ *
+ * \param[in,out] attributes    Attribute structure where \p type will be set.
+ * \param type                  Key type (a \c PSA_KEY_TYPE_XXX value).
+ * \param[in] data              Ignored.
+ * \param data_length           Must be 0.
+ *
+ * \retval #PSA_SUCCESS \emptydescription
+ * \retval #PSA_ERROR_NOT_SUPPORTED \emptydescription
+ */
+static inline psa_status_t MBEDTLS_DEPRECATED psa_set_key_domain_parameters(
+    psa_key_attributes_t *attributes,
+    psa_key_type_t type, const uint8_t *data, size_t data_length)
+{
+    (void) data;
+    if (data_length != 0) {
+        return PSA_ERROR_NOT_SUPPORTED;
+    }
+    psa_set_key_type(attributes, type);
+    return PSA_SUCCESS;
+}
+
+/**
+ * \brief Get domain parameters for a key.
+ *
+ * \deprecated  Mbed TLS no longer supports any domain parameters.
+ *              This function alwaya has an empty output and will be
+ *              removed in a future version of the library.
+
+ * \param[in] attributes        Ignored.
+ * \param[out] data             Ignored.
+ * \param data_size             Ignored.
+ * \param[out] data_length      Set to 0.
+ *
+ * \retval #PSA_SUCCESS \emptydescription
+ */
+static inline psa_status_t MBEDTLS_DEPRECATED psa_get_key_domain_parameters(
+    const psa_key_attributes_t *attributes,
+    uint8_t *data, size_t data_size, size_t *data_length)
+{
+    (void) attributes;
+    (void) data;
+    (void) data_size;
+    *data_length = 0;
+    return PSA_SUCCESS;
+}
+
+/** Safe output buffer size for psa_get_key_domain_parameters().
+ *
+ */
+#define PSA_KEY_DOMAIN_PARAMETERS_SIZE(key_type, key_bits)      \
+    MBEDTLS_DEPRECATED_NUMERIC_CONSTANT(1u)
+#endif /* MBEDTLS_DEPRECATED_REMOVED */
+
+/**@}*/
+
 #ifdef __cplusplus
 }
 #endif

include/psa/crypto_extra.h

@@ -409,140 +409,11 @@ psa_status_t mbedtls_psa_inject_entropy(const uint8_t *seed,
  * @{
  */
 
-/** Custom Diffie-Hellman group.
- *
- * For keys of type #PSA_KEY_TYPE_DH_PUBLIC_KEY(#PSA_DH_FAMILY_CUSTOM) or
- * #PSA_KEY_TYPE_DH_KEY_PAIR(#PSA_DH_FAMILY_CUSTOM), the group data comes
- * from domain parameters set by psa_set_key_domain_parameters().
- */
-#define PSA_DH_FAMILY_CUSTOM             ((psa_dh_family_t) 0x7e)
-
 /** PAKE operation stages. */
 #define PSA_PAKE_OPERATION_STAGE_SETUP 0
 #define PSA_PAKE_OPERATION_STAGE_COLLECT_INPUTS 1
 #define PSA_PAKE_OPERATION_STAGE_COMPUTATION 2
 
-/**
- * \brief Set domain parameters for a key.
- *
- * Some key types require additional domain parameters in addition to
- * the key type identifier and the key size. Use this function instead
- * of psa_set_key_type() when you need to specify domain parameters.
- *
- * The format for the required domain parameters varies based on the key type.
- * Mbed TLS supports the following key type with domain parameters:
- *
- * - For RSA keys (#PSA_KEY_TYPE_RSA_PUBLIC_KEY or #PSA_KEY_TYPE_RSA_KEY_PAIR),
- *   the domain parameter data consists of the public exponent,
- *   represented as a big-endian integer with no leading zeros.
- *   This information is used when generating an RSA key pair.
- *   When importing a key, the public exponent is read from the imported
- *   key data and the exponent recorded in the attribute structure is ignored.
- *   As an exception, the public exponent 65537 is represented by an empty
- *   byte string.
- *
- * \note This function may allocate memory or other resources.
- *       Once you have called this function on an attribute structure,
- *       you must call psa_reset_key_attributes() to free these resources.
- *
- * \note This is an experimental extension to the interface. It may change
- *       in future versions of the library.
- *
- * \note Due to an implementation limitation, domain parameters are ignored
- *       for keys that are managed by a driver.
- *
- * \param[in,out] attributes    Attribute structure where the specified domain
- *                              parameters will be stored.
- *                              If this function fails, the content of
- *                              \p attributes is not modified.
- * \param type                  Key type (a \c PSA_KEY_TYPE_XXX value).
- * \param[in] data              Buffer containing the key domain parameters.
- *                              The content of this buffer is interpreted
- *                              according to \p type as described above.
- * \param data_length           Size of the \p data buffer in bytes.
- *
- * \retval #PSA_SUCCESS \emptydescription
- * \retval #PSA_ERROR_INVALID_ARGUMENT \emptydescription
- * \retval #PSA_ERROR_NOT_SUPPORTED \emptydescription
- * \retval #PSA_ERROR_INSUFFICIENT_MEMORY \emptydescription
- */
-#if !defined(PSA_SET_KEY_DOMAIN_PARAMETERS)
-#define PSA_SET_KEY_DOMAIN_PARAMETERS
-psa_status_t psa_set_key_domain_parameters(psa_key_attributes_t *attributes,
-                                           psa_key_type_t type,
-                                           const uint8_t *data,
-                                           size_t data_length);
-#endif /* PSA_SET_KEY_DOMAIN_PARAMETERS */
-
-/**
- * \brief Get domain parameters for a key.
- *
- * Get the domain parameters for a key with this function, if any. The format
- * of the domain parameters written to \p data is specified in the
- * documentation for psa_set_key_domain_parameters().
- *
- * \note This is an experimental extension to the interface. It may change
- *       in future versions of the library.
- *
- * \note Due to an implementation limitation, domain parameters are not
- *       supported with keys that are managed by a driver.
- *
- * \param[in] attributes        The key attribute structure to query.
- * \param[out] data             On success, the key domain parameters.
- * \param data_size             Size of the \p data buffer in bytes.
- *                              The buffer is guaranteed to be large
- *                              enough if its size in bytes is at least
- *                              the value given by
- *                              PSA_KEY_DOMAIN_PARAMETERS_SIZE().
- * \param[out] data_length      On success, the number of bytes
- *                              that make up the key domain parameters data.
- *
- * \retval #PSA_SUCCESS \emptydescription
- * \retval #PSA_ERROR_BUFFER_TOO_SMALL \emptydescription
- * \retval #PSA_ERROR_NOT_SUPPORTED
- *         The key is managed by a driver.
- */
-psa_status_t psa_get_key_domain_parameters(
-    const psa_key_attributes_t *attributes,
-    uint8_t *data,
-    size_t data_size,
-    size_t *data_length);
-
-/** Safe output buffer size for psa_get_key_domain_parameters().
- *
- * This macro returns a compile-time constant if its arguments are
- * compile-time constants.
- *
- * \warning This function may call its arguments multiple times or
- *          zero times, so you should not pass arguments that contain
- *          side effects.
- *
- * \note This is an experimental extension to the interface. It may change
- *       in future versions of the library.
- *
- * \param key_type  A supported key type.
- * \param key_bits  The size of the key in bits.
- *
- * \return If the parameters are valid and supported, return
- *         a buffer size in bytes that guarantees that
- *         psa_get_key_domain_parameters() will not fail with
- *         #PSA_ERROR_BUFFER_TOO_SMALL.
- *         If the parameters are a valid combination that is not supported
- *         by the implementation, this macro shall return either a
- *         sensible size or 0.
- *         If the parameters are not valid, the
- *         return value is unspecified.
- */
-#define PSA_KEY_DOMAIN_PARAMETERS_SIZE(key_type, key_bits)              \
-    (PSA_KEY_TYPE_IS_RSA(key_type) ? sizeof(int) :                      \
-     PSA_KEY_TYPE_IS_DH(key_type) ? PSA_DH_KEY_DOMAIN_PARAMETERS_SIZE(key_bits) : \
-     PSA_KEY_TYPE_IS_DSA(key_type) ? PSA_DSA_KEY_DOMAIN_PARAMETERS_SIZE(key_bits) : \
-     0)
-#define PSA_DH_KEY_DOMAIN_PARAMETERS_SIZE(key_bits)     \
-    (4 + (PSA_BITS_TO_BYTES(key_bits) + 5) * 3 /*without optional parts*/)
-#define PSA_DSA_KEY_DOMAIN_PARAMETERS_SIZE(key_bits)    \
-    (4 + (PSA_BITS_TO_BYTES(key_bits) + 5) * 2 /*p, g*/ + 34 /*q*/)
-
 /**@}*/
 
 

include/psa/crypto_struct.h

@@ -318,20 +318,6 @@ struct psa_key_attributes_s {
 #if defined(MBEDTLS_PSA_CRYPTO_SE_C)
     psa_key_slot_number_t MBEDTLS_PRIVATE(slot_number);
 #endif /* MBEDTLS_PSA_CRYPTO_SE_C */
-    /* Unlike normal buffers, there are three cases for domain_parameters
-     * and domain_parameters_size:
-     * - domain_parameters_size == SIZE_MAX && domain_parameters == NULL:
-     *   Access to domain parameters is not supported for this key.
-     *   This is a hack which should not exist, intended for keys managed
-     *   by a driver, because drivers don't support domain parameters.
-     * - domain_parameters_size == 0 && domain_parameters == NULL:
-     *   The domain parameters are empty.
-     * - domain_parameters_size > 0 &&
-     *   domain_parameters == valid pointer to domain_parameters_size bytes:
-     *   The domain parameters are non-empty.
-     */
-    void *MBEDTLS_PRIVATE(domain_parameters);
-    size_t MBEDTLS_PRIVATE(domain_parameters_size);
     /* With client/service separation, struct psa_key_attributes_s is
      * marshalled through a transport channel between the client and
      * service side implementation of the PSA Crypto APIs, thus having
@@ -342,9 +328,9 @@ struct psa_key_attributes_s {
 };
 
 #if defined(MBEDTLS_PSA_CRYPTO_SE_C)
-#define PSA_KEY_ATTRIBUTES_INIT { 0, NULL, 0, PSA_CORE_KEY_ATTRIBUTES_INIT }
+#define PSA_KEY_ATTRIBUTES_INIT { 0, PSA_CORE_KEY_ATTRIBUTES_INIT }
 #else
-#define PSA_KEY_ATTRIBUTES_INIT { NULL, 0, PSA_CORE_KEY_ATTRIBUTES_INIT }
+#define PSA_KEY_ATTRIBUTES_INIT { PSA_CORE_KEY_ATTRIBUTES_INIT }
 #endif
 
 static inline struct psa_key_attributes_s psa_key_attributes_init(void)
@@ -437,29 +423,10 @@ static inline psa_algorithm_t psa_get_key_algorithm(
     return attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(policy).MBEDTLS_PRIVATE(alg);
 }
 
-/* This function is declared in crypto_extra.h, which comes after this
- * header file, but we need the function here, so repeat the declaration. */
-#if !defined(PSA_SET_KEY_DOMAIN_PARAMETERS)
-#define PSA_SET_KEY_DOMAIN_PARAMETERS
-psa_status_t psa_set_key_domain_parameters(psa_key_attributes_t *attributes,
-                                           psa_key_type_t type,
-                                           const uint8_t *data,
-                                           size_t data_length);
-#endif /* PSA_SET_KEY_DOMAIN_PARAMETERS */
-
 static inline void psa_set_key_type(psa_key_attributes_t *attributes,
                                     psa_key_type_t type)
 {
-    if (attributes->MBEDTLS_PRIVATE(domain_parameters) == NULL) {
-        /* Common case: quick path */
-        attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(type) = type;
-    } else {
-        /* Call the bigger function to free the old domain parameters.
-         * Ignore any errors which may arise due to type requiring
-         * non-default domain parameters, since this function can't
-         * report errors. */
-        (void) psa_set_key_domain_parameters(attributes, type, NULL, 0);
-    }
+    attributes->MBEDTLS_PRIVATE(core).MBEDTLS_PRIVATE(type) = type;
 }
 
 static inline psa_key_type_t psa_get_key_type(