From f7506416b1311e65d5c440defdbcfe176f633c50 Mon Sep 17 00:00:00 2001 From: Matt Caswell Date: Thu, 3 May 2018 16:00:51 +0100 Subject: [PATCH] Keep the DTLS timer running after the end of the handshake if appropriate During a full handshake the server is the last one to "speak". The timer should continue to run until we know that the client has received our last flight (e.g. because we receive some application data). Reviewed-by: Rich Salz (Merged from https://github.com/openssl/openssl/pull/6170) --- ssl/record/rec_layer_d1.c | 13 +++++++++++++ ssl/statem/statem_lib.c | 18 ++++++++++++++++++ 2 files changed, 31 insertions(+) diff --git a/ssl/record/rec_layer_d1.c b/ssl/record/rec_layer_d1.c index f1e35f407c..37a2eb145e 100644 --- a/ssl/record/rec_layer_d1.c +++ b/ssl/record/rec_layer_d1.c @@ -444,6 +444,19 @@ int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf, && SSL3_RECORD_get_length(rr) != 0) s->rlayer.alert_count = 0; + if (SSL3_RECORD_get_type(rr) != SSL3_RT_HANDSHAKE + && SSL3_RECORD_get_type(rr) != SSL3_RT_CHANGE_CIPHER_SPEC + && !SSL_in_init(s) + && (s->d1->next_timeout.tv_sec != 0 + || s->d1->next_timeout.tv_usec != 0)) { + /* + * The timer is still running but we've received something that isn't + * handshake data - so the peer must have finished processing our + * last handshake flight. Stop the timer. + */ + dtls1_stop_timer(s); + } + /* we now have a packet which can be read and processed */ if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec, diff --git a/ssl/statem/statem_lib.c b/ssl/statem/statem_lib.c index 49b44433f9..74ad6e804a 100644 --- a/ssl/statem/statem_lib.c +++ b/ssl/statem/statem_lib.c @@ -1057,6 +1057,15 @@ WORK_STATE tls_finish_handshake(SSL *s, WORK_STATE wst, int clearbufs, int stop) CRYPTO_atomic_add(&s->ctx->stats.sess_accept_good, 1, &discard, s->ctx->lock); s->handshake_func = ossl_statem_accept; + + if (SSL_IS_DTLS(s) && !s->hit) { + /* + * We are finishing after the client. We start the timer going + * in case there are any retransmits of our final flight + * required. + */ + dtls1_start_timer(s); + } } else { /* * In TLSv1.3 we update the cache as part of processing the @@ -1071,6 +1080,15 @@ WORK_STATE tls_finish_handshake(SSL *s, WORK_STATE wst, int clearbufs, int stop) s->handshake_func = ossl_statem_connect; CRYPTO_atomic_add(&s->session_ctx->stats.sess_connect_good, 1, &discard, s->session_ctx->lock); + + if (SSL_IS_DTLS(s) && s->hit) { + /* + * We are finishing after the server. We start the timer going + * in case there are any retransmits of our final flight + * required. + */ + dtls1_start_timer(s); + } } if (SSL_IS_DTLS(s)) { -- 2.25.1