tests: added check which ensures a client cannot transmit during handshake

Relates #158

Signed-off-by: Nikos Mavrogiannopoulos <nmav@redhat.com>

2 files changed, 296 insertions, 1 deletions

diff --git a/tests/Makefile.am b/tests/Makefile.am
index d0ce446390..6b0ffbcfbf 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -125,7 +125,8 @@ ctests = mini-record-2 simple gc set_pkcs12_cred cert certuniqueid	\
 	 set_known_dh_params_anon set_known_dh_params_psk session-tickets-ok \
 	 session-tickets-missing set_x509_key_file_legacy status-request-ext \
 	 rng-no-onload dtls1-2-mtu-check crl_apis cert_verify_inv_utf8 \
-	 hostname-check-utf8 pkcs8-key-decode-encrypted priority-mix pkcs7
+	 hostname-check-utf8 pkcs8-key-decode-encrypted priority-mix pkcs7 \
+	 send-data-before-handshake
 
 if HAVE_SECCOMP_TESTS
 ctests += dtls-with-seccomp tls-with-seccomp dtls-client-with-seccomp tls-client-with-seccomp
diff --git a/tests/send-data-before-handshake.c b/tests/send-data-before-handshake.c
new file mode 100644
index 0000000000..c127439c99
--- /dev/null
+++ b/tests/send-data-before-handshake.c
@@ -0,0 +1,294 @@
+/*
+ * Copyright (C) 2016 Red Hat, Inc.
+ *
+ * Author: Nikos Mavrogiannopoulos
+ *
+ * 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 General Public License
+ * along with GnuTLS; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#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 <gnutls/dtls.h>
+#include <signal.h>
+#include "cert-common.h"
+#include "utils.h"
+
+static void terminate(void);
+
+/* This program tests that a client cannot send any unencrypted data
+ * during the handshake process. That is to ensure we protect buggy clients
+ * from transmitting sensitive data over the wire.
+ */
+
+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 int handshake_callback(gnutls_session_t session, unsigned int htype,
+	unsigned post, unsigned int incoming, const gnutls_datum_t *msg)
+{
+	int ret;
+	char c = 0;
+
+	if (htype == GNUTLS_HANDSHAKE_FINISHED)
+		return 0;
+
+	/* sending */
+	ret = gnutls_record_send(session, &c, 1);
+	if (ret != GNUTLS_E_UNAVAILABLE_DURING_HANDSHAKE) {
+		fail("gnutls_record_send returned %s/%d at %s\n", gnutls_strerror(ret), ret, gnutls_handshake_description_get_name(htype));
+	} else {
+		success("expected behavior after %s\n", gnutls_handshake_description_get_name(htype));
+	}
+
+	return 0;
+}
+	
+
+#define MAX_BUF 1024
+
+static void client(int fd)
+{
+	int ret;
+	char buffer[MAX_BUF + 1];
+	gnutls_certificate_credentials_t x509_cred;
+	gnutls_session_t session;
+	/* Need to enable anonymous KX specifically. */
+
+	global_init();
+
+	if (debug) {
+		gnutls_global_set_log_function(client_log_func);
+		gnutls_global_set_log_level(7);
+	}
+
+	gnutls_certificate_allocate_credentials(&x509_cred);
+
+	/* Initialize TLS session
+	 */
+	gnutls_init(&session, GNUTLS_CLIENT);
+
+	/* Use default priorities */
+	gnutls_priority_set_direct(session, "NORMAL:-KX-ALL:+ECDHE-RSA", NULL);
+
+	gnutls_handshake_set_hook_function(session, GNUTLS_HANDSHAKE_ANY,
+					   GNUTLS_HOOK_PRE,
+					   handshake_callback);
+
+	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 == GNUTLS_E_UNSUPPORTED_SIGNATURE_ALGORITHM) {
+		/* success */
+		goto end;
+	}
+
+	if (ret < 0) {
+		fail("client: Handshake failed: %s\n", gnutls_strerror(ret));
+		terminate();
+	} else {
+		if (debug)
+			success("client: Handshake was completed\n");
+	}
+
+	if (debug)
+		success("client: TLS version is: %s\n",
+			gnutls_protocol_get_name
+			(gnutls_protocol_get_version(session)));
+
+	do {
+		do {
+			ret = gnutls_record_recv(session, buffer, MAX_BUF);
+		} while (ret == GNUTLS_E_AGAIN
+			 || ret == GNUTLS_E_INTERRUPTED);
+	} while (ret > 0);
+
+	if (ret == 0) {
+		if (debug)
+			success
+			    ("client: Peer has closed the TLS connection\n");
+		goto end;
+	} else if (ret < 0) {
+		fail("client: Error: %s\n", gnutls_strerror(ret));
+		terminate();
+	}
+
+	gnutls_bye(session, GNUTLS_SHUT_WR);
+
+      end:
+
+	close(fd);
+
+	gnutls_deinit(session);
+
+	gnutls_certificate_free_credentials(x509_cred);
+
+	gnutls_global_deinit();
+}
+
+
+/* These are global */
+pid_t child;
+
+static void terminate(void)
+{
+	kill(child, SIGTERM);
+	exit(1);
+}
+
+static void server(int fd)
+{
+	int ret;
+	char buffer[MAX_BUF + 1];
+	gnutls_session_t session;
+	gnutls_certificate_credentials_t x509_cred;
+
+	/* this must be called once in the program
+	 */
+	global_init();
+	memset(buffer, 0, sizeof(buffer));
+
+	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);
+
+	gnutls_init(&session, GNUTLS_SERVER);
+
+	/* avoid calling all the priority functions, since the defaults
+	 * are adequate.
+	 */
+	gnutls_priority_set_direct(session, "NORMAL", NULL);
+
+	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) {
+		/* failure is expected here */
+		goto end;
+	}
+
+	if (debug) {
+		success("server: Handshake was completed\n");
+	}
+
+	if (debug)
+		success("server: TLS version is: %s\n",
+			gnutls_protocol_get_name
+			(gnutls_protocol_get_version(session)));
+
+	/* do not wait for the peer to close the connection.
+	 */
+	gnutls_bye(session, GNUTLS_SHUT_WR);
+
+ end:
+	close(fd);
+	gnutls_deinit(session);
+
+	gnutls_certificate_free_credentials(x509_cred);
+
+	gnutls_global_deinit();
+
+	if (debug)
+		success("server: finished\n");
+}
+
+static void ch_handler(int sig)
+{
+	return;
+}
+
+void doit(void)
+{
+	int fd[2];
+	int ret, status = 0;
+
+	signal(SIGCHLD, ch_handler);
+	signal(SIGPIPE, SIG_IGN);
+
+	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]);
+		client(fd[0]);
+		waitpid(child, &status, 0);
+		check_wait_status(status);
+	} else {
+		close(fd[0]);
+		server(fd[1]);
+		exit(0);
+	}
+}
+
+#endif				/* _WIN32 */