Attest: Align interface to PSA API 1.0

Change the arguments to psa_initial_attest_get_token and
psa_initial_attest_get_token_size as per the PSA 1.0 spec. Update
documentation for new function signature.

Change-Id: Ied6a0bea9ab4a404c147db286584a0873f1a3bf3
Signed-off-by: Raef Coles <raef.coles@arm.com>
diff --git a/interface/include/psa/initial_attestation.h b/interface/include/psa/initial_attestation.h
index aa4a414..c125a4d 100644
--- a/interface/include/psa/initial_attestation.h
+++ b/interface/include/psa/initial_attestation.h
@@ -27,7 +27,7 @@
 /**
  * \brief PSA INITIAL ATTESTATION API version
  *
- * Initial attestation API version is: 1.0-beta-0
+ * Initial attestation API version is: 1.0.0
  */
 #define PSA_INITIAL_ATTEST_API_VERSION_MAJOR (1)
 #define PSA_INITIAL_ATTEST_API_VERSION_MINOR (0)
@@ -42,6 +42,13 @@
 #define PSA_INITIAL_ATTEST_CHALLENGE_SIZE_64  (64u)
 
 /**
+ * The maximum size of an attestation token that can be generated by the
+ * attestation service. Used to configure buffers for services that verify the
+ * produced tokens.
+ */
+#define PSA_INITIAL_ATTEST_MAX_TOKEN_SIZE (0x400)
+
+/**
  * The list of fixed claims in the initial attestation token is still evolving,
  * you can expect slight changes in the future.
  *
@@ -156,25 +163,26 @@
 /**
  * \brief Get initial attestation token
  *
- * \param[in]     challenge_obj   Pointer to buffer where challenge input is
+ * \param[in]     auth_challenge  Pointer to buffer where challenge input is
  *                                stored. Nonce and / or hash of attested data.
  *                                Must be always
  *                                \ref PSA_INITIAL_ATTEST_TOKEN_SIZE bytes
  *                                long.
  * \param[in]     challenge_size  Size of challenge object in bytes.
- * \param[out]    token           Pointer to the buffer where attestation token
- *                                must be stored.
- * \param[in,out] token_size      Size of allocated buffer for token, which
- *                                updated by initial attestation service with
- *                                final token size.
+ * \param[out]    token_buf       Pointer to the buffer where attestation token
+ *                                will be stored.
+ * \param[in]     token_buf_size  Size of allocated buffer for token, in bytes.
+ * \param[out]    token_size      Size of the token that has been returned, in
+ *                                bytes.
  *
  * \return Returns error code as specified in \ref psa_status_t
  */
 psa_status_t
-psa_initial_attest_get_token(const uint8_t *challenge_obj,
-                             uint32_t       challenge_size,
-                             uint8_t       *token,
-                             uint32_t      *token_size);
+psa_initial_attest_get_token(const uint8_t *auth_challenge,
+                             size_t         challenge_size,
+                             uint8_t       *token_buf,
+                             size_t         token_buf_size,
+                             size_t        *token_size);
 
 /**
  * \brief Get the exact size of initial attestation token in bytes.
@@ -182,15 +190,16 @@
  * It just returns with the size of the IAT token. It can be used if the caller
  * dynamically allocates memory for the token buffer.
  *
- * \param[in]   challenge_size  Size of challenge object in bytes.
+ * \param[in]   challenge_size  Size of challenge object in bytes. This must be
+ *                              a supported challenge size (as above).
  * \param[out]  token_size      Size of the token in bytes, which is created by
  *                              initial attestation service.
  *
  * \return Returns error code as specified in \ref psa_status_t
  */
 psa_status_t
-psa_initial_attest_get_token_size(uint32_t  challenge_size,
-                                  uint32_t *token_size);
+psa_initial_attest_get_token_size(size_t  challenge_size,
+                                  size_t *token_size);
 
 /**
  * \brief Get the initial attestation public key.