diff options
| author | Theo Buehler <tb@cvs.openbsd.org> | 2020-05-07 18:56:10 +0000 |
|---|---|---|
| committer | Theo Buehler <tb@cvs.openbsd.org> | 2020-05-07 18:56:10 +0000 |
| commit | fe5304e3fc583a9607068151352458a33ad60c71 (patch) | |
| tree | 2d4a5cc7ffdb8c4ff18bb526ee79329e5cfeb457 | |
| parent | bd9a6584d72883e19b4b3b4db99f0ca1d32abef7 (diff) | |
On receiving a handshake or alert record with empty inner plaintext,
terminate the connection with an unexpected_message alert.
See RFC 8446 section 5.4.
Found with tlsfuzzer
hint/ok jsing
| -rw-r--r-- | lib/libssl/tls13_record_layer.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/lib/libssl/tls13_record_layer.c b/lib/libssl/tls13_record_layer.c index 5c2c2116c04..16a22a841b1 100644 --- a/lib/libssl/tls13_record_layer.c +++ b/lib/libssl/tls13_record_layer.c @@ -1,4 +1,4 @@ -/* $OpenBSD: tls13_record_layer.c,v 1.33 2020/05/03 15:57:25 jsing Exp $ */ +/* $OpenBSD: tls13_record_layer.c,v 1.34 2020/05/07 18:56:09 tb Exp $ */ /* * Copyright (c) 2018, 2019 Joel Sing <jsing@openbsd.org> * @@ -813,6 +813,16 @@ tls13_record_layer_read_record(struct tls13_record_layer *rl) tls13_record_layer_rrec_free(rl); + /* + * On receiving a handshake or alert record with empty inner plaintext, + * we must terminate the connection with an unexpected_message alert. + * See RFC 8446 section 5.4. + */ + if (CBS_len(&rl->rbuf_cbs) == 0 && + (rl->rbuf_content_type == SSL3_RT_ALERT || + rl->rbuf_content_type == SSL3_RT_HANDSHAKE)) + return tls13_send_alert(rl, SSL3_AD_UNEXPECTED_MESSAGE); + switch (rl->rbuf_content_type) { case SSL3_RT_ALERT: return tls13_record_layer_process_alert(rl); |