tls13: Add definition of mbedtls_ssl_{write,read}_early_data
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index dddaaea..ea58661 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -96,15 +96,16 @@
/* Error space gap */
/** Processing of the Certificate handshake message failed. */
#define MBEDTLS_ERR_SSL_BAD_CERTIFICATE -0x7A00
+/* Error space gap */
/**
* Received NewSessionTicket Post Handshake Message.
* This error code is experimental and may be changed or removed without notice.
*/
#define MBEDTLS_ERR_SSL_RECEIVED_NEW_SESSION_TICKET -0x7B00
-/* Error space gap */
-/* Error space gap */
-/* Error space gap */
-/* Error space gap */
+/** Not possible to read early data */
+#define MBEDTLS_ERR_SSL_CANNOT_READ_EARLY_DATA -0x7B80
+/** Not possible to write early data */
+#define MBEDTLS_ERR_SSL_CANNOT_WRITE_EARLY_DATA -0x7C00
/* Error space gap */
/* Error space gap */
/* Error space gap */
@@ -806,14 +807,6 @@
typedef struct mbedtls_ssl_flight_item mbedtls_ssl_flight_item;
#endif
-#if defined(MBEDTLS_SSL_EARLY_DATA) && defined(MBEDTLS_SSL_CLI_C)
-#define MBEDTLS_SSL_EARLY_DATA_STATUS_UNKNOWN 0
-#define MBEDTLS_SSL_EARLY_DATA_STATUS_NOT_SENT 1
-#define MBEDTLS_SSL_EARLY_DATA_STATUS_INDICATION_SENT 2
-#define MBEDTLS_SSL_EARLY_DATA_STATUS_REJECTED 3
-#define MBEDTLS_SSL_EARLY_DATA_STATUS_ACCEPTED 4
-#endif
-
#if defined(MBEDTLS_SSL_PROTO_TLS1_3) && defined(MBEDTLS_SSL_SESSION_TICKETS)
typedef uint8_t mbedtls_ssl_tls13_ticket_flags;
@@ -4897,6 +4890,151 @@
*/
int mbedtls_ssl_close_notify( mbedtls_ssl_context *ssl );
+#if defined(MBEDTLS_SSL_EARLY_DATA)
+
+#if defined(MBEDTLS_SSL_SRV_C)
+/**
+ * \brief Read at most 'len' application data bytes while performing
+ * the handshake (early data).
+ *
+ * \note This function behaves mainly as mbedtls_ssl_read(). The
+ * specification of mbedtls_ssl_read() relevant to TLS 1.3
+ * (thus not the parts specific to (D)TLS 1.2) applies to this
+ * function and the present documentation is restricted to the
+ * differences with mbedtls_ssl_read().
+ *
+ * \param ssl SSL context
+ * \param buf buffer that will hold the data
+ * \param len maximum number of bytes to read
+ *
+ * \return One additional specific return value:
+ * #MBEDTLS_ERR_SSL_CANNOT_READ_EARLY_DATA.
+ *
+ * #MBEDTLS_ERR_SSL_CANNOT_READ_EARLY_DATA is returned when it
+ * is not possible to read early data for the SSL context
+ * \p ssl.
+ *
+ * It may have been possible and it is not possible
+ * anymore because the server received the End of Early Data
+ * message or the maximum number of allowed early data for the
+ * PSK in use has been reached.
+ *
+ * It may never have been possible and will never be possible
+ * for the SSL context \p ssl because the use of early data
+ * is disabled for that context or more generally the context
+ * is not suitably configured to enable early data or the
+ * client does not use early data or the first call to the
+ * function was done while the handshake was already too
+ * advanced to gather and accept early data.
+ *
+ * It is not possible to read early data for the SSL context
+ * \p ssl but this does not preclude for using it with
+ * mbedtls_ssl_write(), mbedtls_ssl_read() or
+ * mbedtls_ssl_handshake().
+ *
+ * \note When a server wants to retrieve early data, it is expected
+ * that this function starts the handshake for the SSL context
+ * \p ssl. But this is not mandatory.
+ *
+ */
+int mbedtls_ssl_read_early_data( mbedtls_ssl_context *ssl,
+ unsigned char *buf, size_t len );
+#endif /* MBEDTLS_SSL_SRV_C */
+
+#if defined(MBEDTLS_SSL_CLI_C)
+/**
+ * \brief Try to write exactly 'len' application data bytes while
+ * performing the handshake (early data).
+ *
+ * \note This function behaves mainly as mbedtls_ssl_write(). The
+ * specification of mbedtls_ssl_write() relevant to TLS 1.3
+ * (thus not the parts specific to (D)TLS1.2) applies to this
+ * function and the present documentation is restricted to the
+ * differences with mbedtls_ssl_write().
+ *
+ * \param ssl SSL context
+ * \param buf buffer holding the data
+ * \param len how many bytes must be written
+ *
+ * \return One additional specific return value:
+ * #MBEDTLS_ERR_SSL_CANNOT_WRITE_EARLY_DATA.
+ *
+ * #MBEDTLS_ERR_SSL_CANNOT_WRITE_EARLY_DATA is returned when it
+ * is not possible to write early data for the SSL context
+ * \p ssl.
+ *
+ * It may have been possible and it is not possible
+ * anymore because the client received the server Finished
+ * message, the server rejected early data or the maximum
+ * number of allowed early data for the PSK in use has been
+ * reached.
+ *
+ * It may never have been possible and will never be possible
+ * for the SSL context \p ssl because the use of early data
+ * is disabled for that context or more generally the context
+ * is not suitably configured to enable early data or the first
+ * call to the function was done while the handshake was
+ * already completed.
+ *
+ * It is not possible to write early data for the SSL context
+ * \p ssl but this does not preclude for using it with
+ * mbedtls_ssl_write(), mbedtls_ssl_read() or
+ * mbedtls_ssl_handshake().
+ *
+ * \note This function may write early data only if the SSL context
+ * has been configured for the handshake with a PSK for which
+ * early data is allowed.
+ *
+ * \note To maximize the number of early data that can be written in
+ * the course of the handshake, it is expected that this
+ * function starts the handshake for the SSL context \p ssl.
+ * But this is not mandatory.
+ *
+ * \note This function does not provide any information on whether
+ * the server has accepted or will accept early data or not.
+ * When it returns a positive value, it just means that it
+ * has written early data to the server. To know whether the
+ * server has accepted early data or not, you should call
+ * mbedtls_ssl_get_early_data_status() with the handshake
+ * completed.
+ */
+int mbedtls_ssl_write_early_data( mbedtls_ssl_context *ssl,
+ const unsigned char *buf, size_t len );
+
+#define MBEDTLS_SSL_EARLY_DATA_STATUS_NOT_SENT 0
+#define MBEDTLS_SSL_EARLY_DATA_STATUS_ACCEPTED 1
+#define MBEDTLS_SSL_EARLY_DATA_STATUS_REJECTED 2
+/**
+ * \brief Get the status of the negotiation of the use of early data.
+ *
+ * \param ssl The SSL context to query
+ *
+ * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if this function is called
+ * from the server-side.
+ *
+ * \return #MBEDTLS_ERR_SSL_BAD_INPUT_DATA if this function is called
+ * prior to completion of the handshake.
+ *
+ * \return #MBEDTLS_SSL_EARLY_DATA_STATUS_NOT_SENT if the client has
+ * not indicated the use of early data to the server.
+ *
+ * \return #MBEDTLS_SSL_EARLY_DATA_STATUS_ACCEPTED if the client has
+ * indicated the use of early data and the server has accepted
+ * it.
+ *
+ * \return #MBEDTLS_SSL_EARLY_DATA_STATUS_REJECTED if the client has
+ * indicated the use of early data but the server has rejected
+ * it. In this situation, the client may want to re-send the
+ * early data it may have tried to send by calling
+ * mbedtls_ssl_write_early_data() as ordinary post-handshake
+ * application data by calling mbedtls_ssl_write().
+ *
+ */
+int mbedtls_ssl_get_early_data_status( mbedtls_ssl_context *ssl );
+#endif /* MBEDTLS_SSL_CLI_C */
+
+#endif /* MBEDTLS_SSL_EARLY_DATA */
+
/**
* \brief Free referenced items in an SSL context and clear memory
*