Simplify handling of remaining record content on switch to legacy stack.

Now that the legacy stack uses struct tls_content, store any remaining
record content directly, rather than fudging up a record that the legacy
stack will process on the next read.

ok kenjiro@ tb@

1 files changed, 13 insertions, 35 deletions

diff --git a/src/lib/libssl/tls13_legacy.c b/src/lib/libssl/tls13_legacy.c
index 6a06330b22..e42600b2cd 100644
--- a/src/lib/libssl/tls13_legacy.c
+++ b/src/lib/libssl/tls13_legacy.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: tls13_legacy.c,v 1.45 2026/04/03 07:17:36 jsing Exp $ */
+/*      $OpenBSD: tls13_legacy.c,v 1.46 2026/08/21 08:50:34 jsing Exp $ */
 /*
  * Copyright (c) 2018, 2019 Joel Sing <jsing@openbsd.org>
  *
@@ -317,51 +317,34 @@ 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))
-                goto err;
+                return 0;
         if (!ssl3_setup_buffers(s))
-                goto err;
+                return 0;
         if (!ssl_init_wbio_buffer(s, 1))
-                goto err;
+                return 0;
 
         /* Stash any unprocessed data from the last record. */
         tls13_record_layer_rcontent(ctx->rl, &cbs);
         if (CBS_len(&cbs) > 0) {
-                if (!CBB_init_fixed(&cbb, s->s3->rbuf.buf,
-                    s->s3->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;
-
-                s->s3->rbuf.offset = SSL3_RT_HEADER_LENGTH;
-                s->s3->rbuf.left = CBS_len(&cbs);
-                s->s3->rrec.type = SSL3_RT_HANDSHAKE;
-                s->s3->rrec.length = CBS_len(&cbs);
-                s->rstate = SSL_ST_READ_BODY;
-                s->packet = s->s3->rbuf.buf;
-                s->packet_length = SSL3_RT_HEADER_LENGTH;
+                if (s->s3->rcontent != NULL)
+                        return 0;
+                if ((s->s3->rcontent = tls_content_new()) == NULL)
+                        return 0;
+                if (!tls_content_dup_data(s->s3->rcontent, 
+                    SSL3_RT_HANDSHAKE, CBS_data(&cbs), CBS_len(&cbs)))
+                        return 0;
         }
 
         /* Stash the current handshake message. */
         tls13_handshake_msg_data(ctx->hs_msg, &cbs);
         if (!BUF_MEM_grow_clean(s->init_buf, CBS_len(&cbs)))
-                goto err;
+                return 0;
         if (!CBS_write_bytes(&cbs, s->init_buf->data,
             s->init_buf->length, NULL))
-                goto err;
+                return 0;
 
         s->s3->hs.tls12.reuse_message = 1;
         s->s3->hs.tls12.message_type = tls13_handshake_msg_type(ctx->hs_msg);
@@ -374,11 +357,6 @@ tls13_use_legacy_stack(struct tls13_ctx *ctx)
         s->method = tls_legacy_method();
 
         return 1;
-
- err:
-        CBB_cleanup(&cbb);
-
-        return 0;
 }
 
 int