handshake-tls13: add session flag to disable sending session ticketstmp-no-auto-send-ticket

While GnuTLS by default implicitly sends NewSessionTicket during
handshake, application protocols like QUIC set a clear boundary
between "in handshake" and "post handshake", and NST must be sent in
the post handshake state.

Signed-off-by: Daiki Ueno <dueno@redhat.com>

5 files changed, 326 insertions, 4 deletions

diff --git a/.gitignore b/.gitignore
index 7c397c517c..a8e03a8ae2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -848,6 +848,7 @@ tests/tls13/psk-dumbfw
 tests/tls13/psk-ext
 tests/tls13/supported_versions
 tests/tls13/tls12-no-tls13-exts
+tests/tls13/no-auto-send-ticket
 tests/tlsext-decoding
 tests/tlsfeature-crt
 tests/tlsfeature-ext
diff --git a/lib/handshake-tls13.c b/lib/handshake-tls13.c
index 24f5af65c6..ea236c803c 100644
--- a/lib/handshake-tls13.c
+++ b/lib/handshake-tls13.c
@@ -510,8 +510,9 @@ int _gnutls13_handshake_server(gnutls_session_t session)
 			_gnutls_set_resumed_parameters(session);
 
 		if (session->internals.hsk_flags & HSK_EARLY_START_USED) {
-			ret = _gnutls13_send_session_ticket(session, TLS13_TICKETS_TO_SEND,
-							    AGAIN(STATE109));
+			if (!(session->internals.flags & GNUTLS_NO_AUTO_SEND_TICKET))
+				ret = _gnutls13_send_session_ticket(session, TLS13_TICKETS_TO_SEND,
+								    AGAIN(STATE109));
 
 			STATE = STATE109;
 			IMED_RET("send session ticket", ret, 0);
@@ -565,7 +566,8 @@ int _gnutls13_handshake_server(gnutls_session_t session)
 
 		FALLTHROUGH;
 	case STATE115:
-		if (!(session->internals.hsk_flags & (HSK_TLS13_TICKET_SENT|HSK_EARLY_START_USED))) {
+		if (!(session->internals.hsk_flags & (HSK_TLS13_TICKET_SENT|HSK_EARLY_START_USED)) &&
+		    !(session->internals.flags & GNUTLS_NO_AUTO_SEND_TICKET)) {
 			ret = _gnutls13_send_session_ticket(session, TLS13_TICKETS_TO_SEND,
 							    AGAIN(STATE115));
 			STATE = STATE115;
diff --git a/lib/includes/gnutls/gnutls.h.in b/lib/includes/gnutls/gnutls.h.in
index a6c3c0ef30..517153634a 100644
--- a/lib/includes/gnutls/gnutls.h.in
+++ b/lib/includes/gnutls/gnutls.h.in
@@ -461,6 +461,8 @@ typedef enum {
  * @GNUTLS_ENABLE_EARLY_DATA: Under TLS1.3 allow the server to receive early data sent as part of the initial ClientHello (0-RTT). 
  *    This is not enabled by default as early data has weaker security properties than other data. Since 3.6.5.
  * @GNUTLS_ENABLE_RAWPK: Allows raw public-keys to be negotiated during the handshake. Since 3.6.6.
+ * @GNUTLS_NO_AUTO_SEND_TICKET: Under TLS1.3 disable auto-sending of
+ *    session tickets during the handshake.
  *
  * Enumeration of different flags for gnutls_init() function. All the flags
  * can be combined except @GNUTLS_SERVER and @GNUTLS_CLIENT which are mutually
@@ -491,7 +493,8 @@ typedef enum {
 	GNUTLS_ENABLE_EARLY_START = (1<<17),
 	GNUTLS_ENABLE_RAWPK = (1<<18),
 	GNUTLS_AUTO_REAUTH = (1<<19),
-	GNUTLS_ENABLE_EARLY_DATA = (1<<20)
+	GNUTLS_ENABLE_EARLY_DATA = (1<<20),
+	GNUTLS_NO_AUTO_SEND_TICKET = (1<<21)
 } gnutls_init_flags_t;
 
 /* compatibility defines (previous versions of gnutls
diff --git a/tests/Makefile.am b/tests/Makefile.am
index c79dcce7e5..ab83e693c4 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -140,6 +140,8 @@ ctests += tls13/psk-dumbfw
 
 ctests += tls13-early-start
 
+ctests += tls13/no-auto-send-ticket
+
 ctests += mini-record-2 simple gnutls_hmac_fast set_pkcs12_cred cert certuniqueid tls-neg-ext-key \
 	 mpi certificate_set_x509_crl dn parse_ca x509-dn x509-dn-decode record-sizes \
 	 hostname-check cve-2008-4989 pkcs12_s2k chainverify record-sizes-range \
diff --git a/tests/tls13/no-auto-send-ticket.c b/tests/tls13/no-auto-send-ticket.c
new file mode 100644
index 0000000000..2602f178a1
--- /dev/null
+++ b/tests/tls13/no-auto-send-ticket.c
@@ -0,0 +1,314 @@
+/*
+ * Copyright (C) 2017-2020 Red Hat, Inc.
+ *
+ * Author: Nikos Mavrogiannopoulos, Daiki Ueno
+ *
+ * This file is part of GnuTLS.
+ *
+ * GnuTLS is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuTLS is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if defined(_WIN32)
+
+int main()
+{
+	exit(77);
+}
+
+#else
+
+#include <string.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+#include <sys/socket.h>
+#include <sys/wait.h>
+#include <arpa/inet.h>
+#include <unistd.h>
+#include <gnutls/gnutls.h>
+#include <signal.h>
+#include <assert.h>
+
+#include "../lib/handshake-defs.h"
+#include "cert-common.h"
+#include "utils.h"
+
+/* This program tests whether the certificate seen in Post Handshake Auth
+ * is found in a resumed session under TLS 1.3.
+ */
+
+static void server_log_func(int level, const char *str)
+{
+	fprintf(stderr, "server|<%d>| %s", level, str);
+}
+
+static void client_log_func(int level, const char *str)
+{
+	fprintf(stderr, "client|<%d>| %s", level, str);
+}
+
+static unsigned tickets_seen = 0;
+static int ticket_callback(gnutls_session_t session, unsigned int htype,
+			   unsigned post, unsigned int incoming, const gnutls_datum_t *msg)
+{
+	gnutls_datum *d;
+	int ret;
+
+	assert(htype == GNUTLS_HANDSHAKE_NEW_SESSION_TICKET);
+
+	d = gnutls_session_get_ptr(session);
+
+	if (post == GNUTLS_HOOK_POST) {
+		tickets_seen++;
+		if (d->data)
+			gnutls_free(d->data);
+		ret = gnutls_session_get_data2(session, d);
+		assert(ret >= 0);
+		assert(d->size > 4);
+
+		return 0;
+	}
+
+	return 0;
+}
+
+static void client(int fd, unsigned flags, unsigned tickets)
+{
+	int ret;
+	gnutls_session_t session;
+	unsigned try = 0;
+	gnutls_datum_t session_data = {NULL, 0};
+	gnutls_certificate_credentials_t x509_cred;
+
+	global_init();
+	tickets_seen = 0;
+
+	if (debug) {
+		gnutls_global_set_log_function(client_log_func);
+		gnutls_global_set_log_level(7);
+	}
+
+	assert(gnutls_certificate_allocate_credentials(&x509_cred)>=0);
+
+ retry:
+	/* Initialize TLS session
+	 */
+	assert(gnutls_init(&session, GNUTLS_CLIENT|flags)>=0);
+
+	gnutls_handshake_set_timeout(session, 20 * 1000);
+
+	ret = gnutls_priority_set_direct(session, "NORMAL:-VERS-ALL:+VERS-TLS1.3:+VERS-TLS1.2:+VERS-TLS1.0", NULL);
+	if (ret < 0)
+		fail("cannot set TLS 1.3 priorities\n");
+
+
+	if (try == 0) {
+		gnutls_session_set_ptr(session, &session_data);
+		gnutls_handshake_set_hook_function(session, GNUTLS_HANDSHAKE_NEW_SESSION_TICKET,
+						   GNUTLS_HOOK_BOTH,
+						   ticket_callback);
+	} else {
+		assert(gnutls_session_set_data(session, session_data.data, session_data.size) >= 0);
+	}
+
+	gnutls_credentials_set(session, GNUTLS_CRD_CERTIFICATE, x509_cred);
+
+	gnutls_transport_set_int(session, fd);
+
+	/* Perform the TLS handshake
+	 */
+	do {
+		ret = gnutls_handshake(session);
+	}
+	while (ret < 0 && gnutls_error_is_fatal(ret) == 0);
+
+	if (ret != 0)
+		fail("handshake failed: %s\n", gnutls_strerror(ret));
+
+	do {
+		ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
+	} while(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED);
+
+	if (ret != 0) {
+		fail("error in recv: %s\n", gnutls_strerror(ret));
+	}
+
+	if (tickets_seen != tickets)
+		fail("unexpected number of tickets received: %u != %u",
+		     tickets_seen, tickets);
+
+	gnutls_deinit(session);
+
+	if (tickets > 0 && try == 0) {
+		try++;
+		goto retry;
+	}
+
+	close(fd);
+	gnutls_free(session_data.data);
+
+	gnutls_global_deinit();
+}
+
+static void server(int fd, unsigned flags,
+		   unsigned tickets_sent, unsigned tickets_expected)
+{
+	int ret;
+	gnutls_session_t session;
+	gnutls_certificate_credentials_t x509_cred;
+	gnutls_datum_t skey;
+
+	/* this must be called once in the program
+	 */
+	global_init();
+
+	assert(gnutls_session_ticket_key_generate(&skey)>=0);
+
+	if (debug) {
+		gnutls_global_set_log_function(server_log_func);
+		gnutls_global_set_log_level(4711);
+	}
+
+	gnutls_certificate_allocate_credentials(&x509_cred);
+	gnutls_certificate_set_x509_key_mem(x509_cred, &server_cert,
+					    &server_key,
+					    GNUTLS_X509_FMT_PEM);
+
+	assert(gnutls_init(&session, GNUTLS_SERVER|flags)>=0);
+
+	assert(gnutls_session_ticket_enable_server(session, &skey) >= 0);
+	gnutls_handshake_set_timeout(session, 20 * 1000);
+
+	assert(gnutls_priority_set_direct(session, "NORMAL:+VERS-TLS1.3", NULL)>=0);
+
+	gnutls_credentials_set(session, GNUTLS_CRD_CERTIFICATE, x509_cred);
+
+	gnutls_transport_set_int(session, fd);
+
+	do {
+		ret = gnutls_handshake(session);
+	} while (ret < 0 && gnutls_error_is_fatal(ret) == 0);
+
+	if (ret != 0)
+		fail("handshake failed: %s\n", gnutls_strerror(ret));
+
+	if (tickets_sent > 0) {
+		do {
+			ret = gnutls_session_ticket_send(session, tickets_sent, 0);
+		} while (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED);
+	}
+
+	do {
+		ret = gnutls_bye(session, GNUTLS_SHUT_RDWR);
+	} while(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED);
+	gnutls_deinit(session);
+
+	if (tickets_expected > 0) {
+		/* resume session
+		 */
+		assert(gnutls_init(&session, GNUTLS_SERVER|flags)>=0);
+
+		assert(gnutls_session_ticket_enable_server(session, &skey) >= 0);
+		gnutls_handshake_set_timeout(session, 20 * 1000);
+		assert(gnutls_priority_set_direct(session, "NORMAL:+VERS-TLS1.3", NULL)>=0);
+
+		gnutls_credentials_set(session, GNUTLS_CRD_CERTIFICATE, x509_cred);
+
+		gnutls_transport_set_int(session, fd);
+
+		do {
+			ret = gnutls_handshake(session);
+		} while (ret < 0 && gnutls_error_is_fatal(ret) == 0);
+
+		if (ret != 0)
+			fail("handshake failed: %s\n", gnutls_strerror(ret));
+
+		assert(gnutls_session_is_resumed(session) != 0);
+
+		gnutls_bye(session, GNUTLS_SHUT_RDWR);
+		gnutls_deinit(session);
+	}
+
+	gnutls_free(skey.data);
+	close(fd);
+	gnutls_certificate_free_credentials(x509_cred);
+
+	gnutls_global_deinit();
+
+	if (debug)
+		success("server: client/server hello were verified\n");
+}
+
+static void ch_handler(int sig)
+{
+	int status = 0;
+	wait(&status);
+	check_wait_status(status);
+	return;
+}
+
+static void start(const char *name,
+		  unsigned flags,
+		  unsigned tickets_sent,
+		  unsigned tickets_expected)
+{
+	int fd[2];
+	int ret;
+	pid_t child;
+
+	success("testing: %s\n", name);
+
+	ret = socketpair(AF_UNIX, SOCK_STREAM, 0, fd);
+	if (ret < 0) {
+		perror("socketpair");
+		exit(1);
+	}
+
+	child = fork();
+	if (child < 0) {
+		perror("fork");
+		fail("fork");
+		exit(1);
+	}
+
+	if (child) {
+		/* parent */
+		close(fd[1]);
+		server(fd[0], flags, tickets_sent, tickets_expected);
+		kill(child, SIGTERM);
+	} else {
+		close(fd[0]);
+		client(fd[1], flags, tickets_expected);
+		exit(0);
+	}
+
+}
+
+void doit(void)
+{
+	signal(SIGCHLD, ch_handler);
+	signal(SIGPIPE, SIG_IGN);
+
+	start("auto send ticket 0", 0, 0, TLS13_TICKETS_TO_SEND);
+	start("auto send ticket 1", 0, 1, TLS13_TICKETS_TO_SEND + 1);
+	start("no auto send ticket 0", GNUTLS_NO_AUTO_SEND_TICKET, 0, 0);
+	start("no auto send ticket 1", GNUTLS_NO_AUTO_SEND_TICKET, 1, 1);
+}
+#endif				/* _WIN32 */