Implement legacy fallback for the TLS 1.3 client.

If the Server Hello received indicates that the server did not negotiate
TLS 1.3, fallback to the original TLS client implementation.

ok bcook@, tb@

1 files changed, 2 insertions, 1 deletions

diff --git a/src/lib/libssl/tls13_internal.h b/src/lib/libssl/tls13_internal.h
index 1fe8f547a1..c9ef37a39f 100644
--- a/src/lib/libssl/tls13_internal.h
+++ b/src/lib/libssl/tls13_internal.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: tls13_internal.h,v 1.26 2019/03/17 15:13:23 jsing Exp $ */
+/* $OpenBSD: tls13_internal.h,v 1.27 2019/04/04 16:53:57 jsing Exp $ */
 /*
  * Copyright (c) 2018 Bob Beck <beck@openbsd.org>
  * Copyright (c) 2018 Theo Buehler <tb@openbsd.org>
@@ -35,6 +35,7 @@ __BEGIN_HIDDEN_DECLS
 #define TLS13_IO_FAILURE        -1
 #define TLS13_IO_WANT_POLLIN    -2
 #define TLS13_IO_WANT_POLLOUT   -3
+#define TLS13_IO_USE_LEGACY     -4
 
 typedef void (*tls13_alert_cb)(uint8_t _alert_desc, void *_cb_arg);
 typedef int (*tls13_post_handshake_cb)(void *_cb_arg);