Use tls_buffer for alert and handshake fragments in the legacy stack.

This avoids a bunch of pointer munging and a handrolled memmove.

ok tb@

1 files changed, 10 insertions, 1 deletions

diff --git a/src/lib/libssl/tls_buffer.c b/src/lib/libssl/tls_buffer.c
index f70cfbc1a0..517d66d685 100644
--- a/src/lib/libssl/tls_buffer.c
+++ b/src/lib/libssl/tls_buffer.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: tls_buffer.c,v 1.3 2022/07/22 19:33:53 jsing Exp $ */
+/* $OpenBSD: tls_buffer.c,v 1.4 2022/11/10 18:06:37 jsing Exp $ */
 /*
  * Copyright (c) 2018, 2019, 2022 Joel Sing <jsing@openbsd.org>
  *
@@ -155,6 +155,15 @@ tls_buffer_extend(struct tls_buffer *buf, size_t len,
         }
 }
 
+size_t
+tls_buffer_remaining(struct tls_buffer *buf)
+{
+        if (buf->offset > buf->len)
+                return 0;
+
+        return buf->len - buf->offset;
+}
+
 ssize_t
 tls_buffer_read(struct tls_buffer *buf, uint8_t *rbuf, size_t n)
 {