From abdcc1624b7c33c3da0852e937f676bf1b08b619 Mon Sep 17 00:00:00 2001 From: jsing Date: Sat, 25 Jan 2020 12:37:06 +0000 Subject: Only discard the extension block for client hello and server hello messages. TLSv1.3 messages that include extensions need a length prefixed field with zero bytes, rather than no data at all. ok beck@ tb@ --- lib/libssl/ssl_tlsext.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/lib/libssl/ssl_tlsext.c b/lib/libssl/ssl_tlsext.c index b76a48b99aa..24f2bd50226 100644 --- a/lib/libssl/ssl_tlsext.c +++ b/lib/libssl/ssl_tlsext.c @@ -1,4 +1,4 @@ -/* $OpenBSD: ssl_tlsext.c,v 1.55 2020/01/25 12:31:42 jsing Exp $ */ +/* $OpenBSD: ssl_tlsext.c,v 1.56 2020/01/25 12:37:06 jsing Exp $ */ /* * Copyright (c) 2016, 2017, 2019 Joel Sing * Copyright (c) 2017 Doug Hogan @@ -1918,7 +1918,8 @@ tlsext_build(SSL *s, CBB *cbb, int is_server, uint16_t msg_type) extensions_present = 1; } - if (!extensions_present) + if (!extensions_present && + (msg_type & (SSL_TLSEXT_MSG_CH | SSL_TLSEXT_MSG_SH)) != 0) CBB_discard_child(cbb); if (!CBB_flush(cbb)) -- cgit v1.2.3-59-g8ed1b