Use CBS to parse TLS alerts in the legacy stack.

ok tb@

1 files changed, 10 insertions, 4 deletions

diff --git a/src/lib/libssl/ssl_pkt.c b/src/lib/libssl/ssl_pkt.c
index 3dd0269540..4ec22f7d53 100644
--- a/src/lib/libssl/ssl_pkt.c
+++ b/src/lib/libssl/ssl_pkt.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_pkt.c,v 1.58 2022/03/26 15:05:53 jsing Exp $ */
+/* $OpenBSD: ssl_pkt.c,v 1.59 2022/09/10 15:37:13 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -690,6 +690,7 @@ ssl3_read_alert(SSL *s)
 {
         SSL3_RECORD_INTERNAL *rr = &s->s3->rrec;
         uint8_t alert_level, alert_descr;
+        CBS cbs;
 
         /*
          * TLSv1.2 permits an alert to be fragmented across multiple records or
@@ -713,10 +714,15 @@ ssl3_read_alert(SSL *s)
                 return 1;
         }
 
-        ssl_msg_callback(s, 0, SSL3_RT_ALERT, s->s3->alert_fragment, 2);
+        CBS_init(&cbs, s->s3->alert_fragment, sizeof(s->s3->alert_fragment));
+
+        ssl_msg_callback_cbs(s, 0, SSL3_RT_ALERT, &cbs);
+
+        if (!CBS_get_u8(&cbs, &alert_level))
+                return -1;
+        if (!CBS_get_u8(&cbs, &alert_descr))
+                return -1;
 
-        alert_level = s->s3->alert_fragment[0];
-        alert_descr = s->s3->alert_fragment[1];
         s->s3->alert_fragment_len = 0;
 
         ssl_info_callback(s, SSL_CB_READ_ALERT,