Add wait flight2 state.

The state is come from RFC8446 section A.2 Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
Mbed-TLS · Jan 5, 2023 · 37e80b3 · 37e80b3
1 parent c74f2f5
commit 37e80b3
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Showing 2 changed files with 46 additions and 1 deletion.
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
@@ -668,11 +668,11 @@ typedef enum
     MBEDTLS_SSL_SERVER_FINISHED,
     MBEDTLS_SSL_FLUSH_BUFFERS,
     MBEDTLS_SSL_HANDSHAKE_WRAPUP,
-
     MBEDTLS_SSL_NEW_SESSION_TICKET,
     MBEDTLS_SSL_SERVER_HELLO_VERIFY_REQUEST_SENT,
     MBEDTLS_SSL_HELLO_RETRY_REQUEST,
     MBEDTLS_SSL_ENCRYPTED_EXTENSIONS,
+    MBEDTLS_SSL_WAIT_FLIGHT2,
     MBEDTLS_SSL_CLIENT_CERTIFICATE_VERIFY,
     MBEDTLS_SSL_CLIENT_CCS_AFTER_SERVER_FINISHED,
     MBEDTLS_SSL_CLIENT_CCS_BEFORE_2ND_CLIENT_HELLO,

diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c
@@ -2677,6 +2677,30 @@ static int ssl_tls13_write_server_finished( mbedtls_ssl_context *ssl )
     MBEDTLS_SSL_DEBUG_MSG( 1, ( "Switch to handshake keys for inbound traffic" ) );
     mbedtls_ssl_set_inbound_transform( ssl, ssl->handshake->transform_handshake );
 
+    mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_WAIT_FLIGHT2 );
+
+    return( 0 );
+}
+
+/*
+ * Handler for MBEDTLS_SSL_WAIT_FLIGHT2
+ *
+ * RFC 8446 section A.2
+ *
+ *                      WAIT_FLIGHT2
+ *                            |
+ *                   +--------+--------+
+ *           No auth |                 | Client auth
+ *                   |                 |
+ *                   |                 v
+ *                   |             WAIT_CERT
+ *                   |        Recv |       | Recv Certificate
+ */
+MBEDTLS_CHECK_RETURN_CRITICAL
+static int ssl_tls13_process_wait_flight2( mbedtls_ssl_context *ssl )
+{
+    MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> ssl_tls13_process_wait_flight2" ) );
+
     if( ssl->handshake->certificate_request_sent )
         mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_CLIENT_CERTIFICATE );
     else
@@ -2686,6 +2710,7 @@ static int ssl_tls13_write_server_finished( mbedtls_ssl_context *ssl )
         mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_CLIENT_FINISHED );
     }
 
+    MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= ssl_tls13_process_wait_flight2" ) );
     return( 0 );
 }
 
@@ -3098,10 +3123,30 @@ int mbedtls_ssl_tls13_handshake_server_step( mbedtls_ssl_context *ssl )
             break;
 #endif /* MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE */
 
+        /* RFC 8446 section A.2
+         *
+         *                                 | Send Finished ( SERVER_FINISHED )
+         *                                 | K_send = application
+         *                        +--------+--------+
+         *               No 0-RTT |                 | 0-RTT
+         *                        |                 |
+         *    K_recv = handshake  |                 | K_recv = early data
+         *  [Skip decrypt errors] |    +------> WAIT_EOED -+
+         *                        |    |       Recv |      | Recv EndOfEarlyData
+         *                        |    | early data |      | K_recv = handshake
+         *                        |    +------------+      |
+         *                        |                        |
+         *                        +> WAIT_FLIGHT2 <--------+
+         *                                 |
+         */
         case MBEDTLS_SSL_SERVER_FINISHED:
             ret = ssl_tls13_write_server_finished( ssl );
             break;
 
+        case MBEDTLS_SSL_WAIT_FLIGHT2:
+            ret = ssl_tls13_process_wait_flight2( ssl );
+            break;
+
         case MBEDTLS_SSL_CLIENT_FINISHED:
             ret = ssl_tls13_process_client_finished( ssl );
             break;