1 files changed, 25 insertions, 1 deletions

diff --git a/src/lib/libssl/tls13_legacy.c b/src/lib/libssl/tls13_legacy.c
index 3368600c60..f668dd4ea3 100644
--- a/src/lib/libssl/tls13_legacy.c
+++ b/src/lib/libssl/tls13_legacy.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: tls13_legacy.c,v 1.30 2021/09/14 14:31:21 tb Exp $ */
+/*      $OpenBSD: tls13_legacy.c,v 1.31 2021/09/16 19:25:30 jsing Exp $ */
 /*
  * Copyright (c) 2018, 2019 Joel Sing <jsing@openbsd.org>
  *
@@ -96,6 +96,30 @@ tls13_legacy_wire_write_cb(const void *buf, size_t n, void *arg)
         return tls13_legacy_wire_write(ctx->ssl, buf, n);
 }
 
+static ssize_t
+tls13_legacy_wire_flush(SSL *ssl)
+{
+        if (BIO_flush(ssl->wbio) <= 0) {
+                if (BIO_should_write(ssl->wbio))
+                        return TLS13_IO_WANT_POLLOUT;
+
+                if (ERR_peek_error() == 0 && errno != 0)
+                        SYSerror(errno);
+
+                return TLS13_IO_FAILURE;
+        }
+
+        return TLS13_IO_SUCCESS;
+}
+
+ssize_t
+tls13_legacy_wire_flush_cb(void *arg)
+{
+        struct tls13_ctx *ctx = arg;
+
+        return tls13_legacy_wire_flush(ctx->ssl);
+}
+
 static void
 tls13_legacy_error(SSL *ssl)
 {