1 files changed, 27 insertions, 9 deletions

diff --git a/src/lib/libssl/tls13_legacy.c b/src/lib/libssl/tls13_legacy.c
index 317a1cb0f5..a26afeeeb9 100644
--- a/src/lib/libssl/tls13_legacy.c
+++ b/src/lib/libssl/tls13_legacy.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: tls13_legacy.c,v 1.13 2020/09/13 15:04:35 jsing Exp $ */
+/*      $OpenBSD: tls13_legacy.c,v 1.14 2020/10/07 07:46:18 jsing Exp $ */
 /*
  * Copyright (c) 2018, 2019 Joel Sing <jsing@openbsd.org>
  *
@@ -297,22 +297,35 @@ static int
 tls13_use_legacy_stack(struct tls13_ctx *ctx)
 {
         SSL *s = ctx->ssl;
+        CBB cbb, fragment;
         CBS cbs;
 
+        memset(&cbb, 0, sizeof(cbb));
+
         if (!ssl3_setup_init_buffer(s))
-                return 0;
+                goto err;
         if (!ssl3_setup_buffers(s))
-                return 0;
+                goto err;
         if (!ssl_init_wbio_buffer(s, 1))
-                return 0;
+                goto err;
 
         /* Stash any unprocessed data from the last record. */
         tls13_record_layer_rbuf(ctx->rl, &cbs);
         if (CBS_len(&cbs) > 0) {
-                if (!CBS_write_bytes(&cbs,
-                    S3I(s)->rbuf.buf + SSL3_RT_HEADER_LENGTH,
-                    S3I(s)->rbuf.len - SSL3_RT_HEADER_LENGTH, NULL))
-                        return 0;
+                if (!CBB_init_fixed(&cbb, S3I(s)->rbuf.buf,
+                    S3I(s)->rbuf.len))
+                        goto err;
+                if (!CBB_add_u8(&cbb, SSL3_RT_HANDSHAKE))
+                        goto err;
+                if (!CBB_add_u16(&cbb, TLS1_2_VERSION))
+                        goto err;
+                if (!CBB_add_u16_length_prefixed(&cbb, &fragment))
+                        goto err;
+                if (!CBB_add_bytes(&fragment, CBS_data(&cbs),
+                    CBS_len(&cbs)))
+                        goto err;
+                if (!CBB_finish(&cbb, NULL, NULL))
+                        goto err;
 
                 S3I(s)->rbuf.offset = SSL3_RT_HEADER_LENGTH;
                 S3I(s)->rbuf.left = CBS_len(&cbs);
@@ -328,13 +341,18 @@ tls13_use_legacy_stack(struct tls13_ctx *ctx)
         tls13_handshake_msg_data(ctx->hs_msg, &cbs);
         if (!CBS_write_bytes(&cbs, s->internal->init_buf->data,
             s->internal->init_buf->length, NULL))
-                return 0;
+                goto err;
 
         S3I(s)->tmp.reuse_message = 1;
         S3I(s)->tmp.message_type = tls13_handshake_msg_type(ctx->hs_msg);
         S3I(s)->tmp.message_size = CBS_len(&cbs);
 
         return 1;
+
+ err:
+        CBB_cleanup(&cbb);
+
+        return 0;
 }
 
 int