Fix minor errors in key derivation and key agreement documentation
diff --git a/include/psa/crypto.h b/include/psa/crypto.h
index 3ed5f0f..b2f3eb2 100644
--- a/include/psa/crypto.h
+++ b/include/psa/crypto.h
@@ -3129,9 +3129,9 @@
* public key type corresponding to the type of
* private_key. That is, this function performs the
* equivalent of
- * `psa_import_key(internal_public_key_handle,
- * PSA_KEY_TYPE_PUBLIC_KEY_OF_KEYPAIR(private_key_type),
- * peer_key, peer_key_length)` where
+ * #psa_import_key(`internal_public_key_handle`,
+ * #PSA_KEY_TYPE_PUBLIC_KEY_OF_KEYPAIR(`private_key_type`),
+ * `peer_key`, `peer_key_length`) where
* `private_key_type` is the type of `private_key`.
* For example, for EC keys, this means that peer_key
* is interpreted as a point on the curve that the
@@ -3175,6 +3175,10 @@
* a key derivation, use psa_key_agreement() and other functions from
* the key derivation and generator interface.
*
+ * \param alg The key agreement algorithm to compute
+ * (\c PSA_ALG_XXX value such that
+ * #PSA_ALG_IS_RAW_KEY_AGREEMENT(\p alg)
+ * is true).
* \param private_key Handle to the private key to use.
* \param[in] peer_key Public key of the peer. It must be
* in the same format that psa_import_key()
diff --git a/include/psa/crypto_values.h b/include/psa/crypto_values.h
index 76c5f38..29a64c2 100644
--- a/include/psa/crypto_values.h
+++ b/include/psa/crypto_values.h
@@ -613,7 +613,6 @@
#define PSA_ALG_IS_ASYMMETRIC_ENCRYPTION(alg) \
(((alg) & PSA_ALG_CATEGORY_MASK) == PSA_ALG_CATEGORY_ASYMMETRIC_ENCRYPTION)
-#define PSA_ALG_KEY_SELECTION_FLAG ((psa_algorithm_t)0x01000000)
/** Whether the specified algorithm is a key agreement algorithm.
*
* \param alg An algorithm identifier (value of type #psa_algorithm_t).
@@ -623,8 +622,7 @@
* algorithm identifier.
*/
#define PSA_ALG_IS_KEY_AGREEMENT(alg) \
- (((alg) & PSA_ALG_CATEGORY_MASK & ~PSA_ALG_KEY_SELECTION_FLAG) == \
- PSA_ALG_CATEGORY_KEY_AGREEMENT)
+ (((alg) & PSA_ALG_CATEGORY_MASK) == PSA_ALG_CATEGORY_KEY_AGREEMENT)
/** Whether the specified algorithm is a key derivation algorithm.
*
@@ -637,17 +635,6 @@
#define PSA_ALG_IS_KEY_DERIVATION(alg) \
(((alg) & PSA_ALG_CATEGORY_MASK) == PSA_ALG_CATEGORY_KEY_DERIVATION)
-/** Whether the specified algorithm is a key selection algorithm.
- *
- * \param alg An algorithm identifier (value of type #psa_algorithm_t).
- *
- * \return 1 if \p alg is a key selection algorithm, 0 otherwise.
- * This macro may return either 0 or 1 if \p alg is not a supported
- * algorithm identifier.
- */
-#define PSA_ALG_IS_KEY_SELECTION(alg) \
- (((alg) & PSA_ALG_CATEGORY_MASK) == PSA_ALG_CATEGORY_KEY_SELECTION)
-
#define PSA_ALG_HASH_MASK ((psa_algorithm_t)0x000000ff)
#define PSA_ALG_MD2 ((psa_algorithm_t)0x01000001)
@@ -1313,8 +1300,23 @@
#define PSA_ALG_KEY_AGREEMENT_GET_BASE(alg) \
(((alg) & PSA_ALG_KEY_AGREEMENT_MASK) | PSA_ALG_CATEGORY_KEY_AGREEMENT)
+/** Whether the specified algorithm is a raw key agreement algorithm.
+ *
+ * A raw key agreement algorithm is one that does not specify
+ * a key derivation function.
+ * Usually, raw key agreement algorithms are constructed directly with
+ * a \c PSA_ALG_xxx macro while non-raw key agreement algorithms are
+ * constructed with PSA_ALG_KEY_AGREEMENT().
+ *
+ * \param alg An algorithm identifier (value of type #psa_algorithm_t).
+ *
+ * \return 1 if \p alg is a raw key agreement algorithm, 0 otherwise.
+ * This macro may return either 0 or 1 if \p alg is not a supported
+ * algorithm identifier.
+ */
#define PSA_ALG_IS_RAW_KEY_AGREEMENT(alg) \
- (PSA_ALG_KEY_AGREEMENT_GET_KDF(alg) == PSA_ALG_CATEGORY_KEY_DERIVATION)
+ (PSA_ALG_IS_KEY_AGREEMENT(alg) && \
+ PSA_ALG_KEY_AGREEMENT_GET_KDF(alg) == PSA_ALG_CATEGORY_KEY_DERIVATION)
#define PSA_ALG_IS_KEY_DERIVATION_OR_AGREEMENT(alg) \
((PSA_ALG_IS_KEY_DERIVATION(alg) || PSA_ALG_IS_KEY_AGREEMENT(alg)))