record: new gnutls_record_send2 functiontmp-draft-ietf-tls-tls13-21-dueno-padding-2

This adds a new function gnutls_record_send2() which takes an extra
argument to specify the padding size of the record.

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

8 files changed, 375 insertions, 4 deletions

diff --git a/doc/Makefile.am b/doc/Makefile.am
index c609b23d02..2f102b9bcc 100644
--- a/doc/Makefile.am
+++ b/doc/Makefile.am
@@ -1774,6 +1774,8 @@ FUNCS += functions/gnutls_record_recv_seq
 FUNCS += functions/gnutls_record_recv_seq.short
 FUNCS += functions/gnutls_record_send
 FUNCS += functions/gnutls_record_send.short
+FUNCS += functions/gnutls_record_send2
+FUNCS += functions/gnutls_record_send2.short
 FUNCS += functions/gnutls_record_send_range
 FUNCS += functions/gnutls_record_send_range.short
 FUNCS += functions/gnutls_record_set_max_size
diff --git a/doc/manpages/Makefile.am b/doc/manpages/Makefile.am
index 98cb81d984..3d6802f2c2 100644
--- a/doc/manpages/Makefile.am
+++ b/doc/manpages/Makefile.am
@@ -683,6 +683,7 @@ APIMANS += gnutls_record_recv.3
 APIMANS += gnutls_record_recv_packet.3
 APIMANS += gnutls_record_recv_seq.3
 APIMANS += gnutls_record_send.3
+APIMANS += gnutls_record_send2.3
 APIMANS += gnutls_record_send_range.3
 APIMANS += gnutls_record_set_max_size.3
 APIMANS += gnutls_record_set_state.3
diff --git a/lib/includes/gnutls/gnutls.h.in b/lib/includes/gnutls/gnutls.h.in
index 338a1b0ff7..2043ea2212 100644
--- a/lib/includes/gnutls/gnutls.h.in
+++ b/lib/includes/gnutls/gnutls.h.in
@@ -1237,6 +1237,8 @@ int gnutls_range_split(gnutls_session_t session,
 
 ssize_t gnutls_record_send(gnutls_session_t session, const void *data,
 			   size_t data_size);
+ssize_t gnutls_record_send2(gnutls_session_t session, const void *data,
+			    size_t data_size, size_t pad, unsigned flags);
 ssize_t gnutls_record_send_range(gnutls_session_t session,
 				 const void *data, size_t data_size,
 				 const gnutls_range_st * range);
diff --git a/lib/libgnutls.map b/lib/libgnutls.map
index 1cc6137a50..282261b9c7 100644
--- a/lib/libgnutls.map
+++ b/lib/libgnutls.map
@@ -1214,6 +1214,7 @@ GNUTLS_3_6_xx
 	gnutls_certificate_set_ocsp_status_request_file2;
 	gnutls_certificate_set_ocsp_status_request_mem;
 	gnutls_certificate_get_ocsp_expiration;
+	gnutls_record_send2;
 } GNUTLS_3_6_2;
 
 GNUTLS_FIPS140_3_4 {
diff --git a/lib/record.c b/lib/record.c
index 3e2af9300c..577a15aef8 100644
--- a/lib/record.c
+++ b/lib/record.c
@@ -1707,6 +1707,33 @@ ssize_t
 gnutls_record_send(gnutls_session_t session, const void *data,
 		   size_t data_size)
 {
+	return gnutls_record_send2(session, data, data_size, 0, 0);
+}
+
+/**
+ * gnutls_record_send2:
+ * @session: is a #gnutls_session_t type.
+ * @data: contains the data to send
+ * @data_size: is the length of the data
+ * @pad: padding to be added to the record
+ * @flags: must be zero
+ *
+ * This function is identical to gnutls_record_send() except that it
+ * takes an extra argument to specify padding to be added the record.
+ * To determine the maximum size of padding, use
+ * gnutls_record_get_max_size() and gnutls_record_overhead_size().
+ *
+ * Returns: The number of bytes sent, or a negative error code.  The
+ *   number of bytes sent might be less than @data_size.  The maximum
+ *   number of bytes this function can send in a single call depends
+ *   on the negotiated maximum record size.
+ **/
+ssize_t
+gnutls_record_send2(gnutls_session_t session, const void *data,
+		    size_t data_size, size_t pad, unsigned flags)
+{
+	const version_entry_st *vers = get_version(session);
+	size_t max_pad = 0;
 	int ret;
 
 	if (unlikely(!session->internals.initial_negotiation_completed)) {
@@ -1717,11 +1744,20 @@ gnutls_record_send(gnutls_session_t session, const void *data,
 			return gnutls_assert_val(GNUTLS_E_UNAVAILABLE_DURING_HANDSHAKE);
 	}
 
+	if (unlikely(!vers))
+		return gnutls_assert_val(GNUTLS_E_INTERNAL_ERROR);
+
+	if (vers->tls13_sem)
+		max_pad = gnutls_record_get_max_size(session) - gnutls_record_overhead_size(session);
+
+	if (pad > max_pad)
+		return gnutls_assert_val(GNUTLS_E_INVALID_REQUEST);
+
 	switch(session->internals.rsend_state) {
 		case RECORD_SEND_NORMAL:
-			return _gnutls_send_int(session, GNUTLS_APPLICATION_DATA,
-						-1, EPOCH_WRITE_CURRENT, data,
-						data_size, MBUFFER_FLUSH);
+			return _gnutls_send_tlen_int(session, GNUTLS_APPLICATION_DATA,
+						     -1, EPOCH_WRITE_CURRENT, data,
+						     data_size, pad, MBUFFER_FLUSH);
 		case RECORD_SEND_CORKED:
 		case RECORD_SEND_CORKED_TO_KU:
 			return append_data_to_corked(session, data, data_size);
diff --git a/symbols.last b/symbols.last
index acb043adeb..01ff6c913b 100644
--- a/symbols.last
+++ b/symbols.last
@@ -661,6 +661,7 @@ gnutls_record_overhead_size@GNUTLS_3_4
 gnutls_record_recv@GNUTLS_3_4
 gnutls_record_recv_packet@GNUTLS_3_4
 gnutls_record_recv_seq@GNUTLS_3_4
+gnutls_record_send2@GNUTLS_3_6_xx
 gnutls_record_send@GNUTLS_3_4
 gnutls_record_send_range@GNUTLS_3_4
 gnutls_record_set_max_size@GNUTLS_3_4
diff --git a/tests/Makefile.am b/tests/Makefile.am
index a3c2b3e740..b87e1aea41 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -181,7 +181,7 @@ ctests += mini-record-2 simple gc set_pkcs12_cred cert certuniqueid tls-neg-ext-
 	 send-data-before-handshake recv-data-before-handshake crt_inv_write \
 	 x509sign-verify-error rng-op-nonce rng-op-random rng-op-key x509-dn-decode-compat \
 	 ip-check mini-x509-ipaddr trust-store base64-raw random-art dhex509self \
-	 dss-sig-val sign-pk-api tls-session-ext-override
+	 dss-sig-val sign-pk-api tls-session-ext-override mini-record-pad
 
 if HAVE_SECCOMP_TESTS
 ctests += dtls-with-seccomp tls-with-seccomp dtls-client-with-seccomp tls-client-with-seccomp
diff --git a/tests/mini-record-pad.c b/tests/mini-record-pad.c
new file mode 100644
index 0000000000..275ec70e06
--- /dev/null
+++ b/tests/mini-record-pad.c
@@ -0,0 +1,328 @@
+/*
+ * Copyright (C) 2012-2018 Free Software Foundation, 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 <http://www.gnu.org/licenses/>
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#if defined(_WIN32)
+
+int main(void)
+{
+	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"
+
+#define MAX_BUF 1024
+#define HIGH(x) (3*x)
+static void terminate(void);
+static size_t total;
+
+/* This program tests the robustness of record sending with padding.
+ */
+
+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);
+}
+
+
+/* A very basic TLS client, with anonymous authentication.
+ */
+
+
+
+static ssize_t
+push(gnutls_transport_ptr_t tr, const void *data, size_t len)
+{
+	int fd = (long int) tr;
+
+	total += len;
+	return send(fd, data, len, 0);
+}
+
+static void client(int fd, const char *prio)
+{
+	int ret;
+	char buffer[MAX_BUF + 1];
+	gnutls_anon_client_credentials_t anoncred;
+	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_anon_allocate_client_credentials(&anoncred);
+	gnutls_certificate_allocate_credentials(&x509_cred);
+
+	/* Initialize TLS session
+	 */
+	gnutls_init(&session, GNUTLS_CLIENT);
+
+	/* Use default priorities */
+	gnutls_priority_set_direct(session, prio, NULL);
+
+	/* put the anonymous credentials to the current session
+	 */
+	gnutls_credentials_set(session, GNUTLS_CRD_ANON, anoncred);
+	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("client: Handshake failed\n");
+		gnutls_perror(ret);
+		exit(1);
+	} 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) {
+		if (ret != 0) {
+			fail("client: Error: %s\n", gnutls_strerror(ret));
+			exit(1);
+		}
+	}
+
+	gnutls_bye(session, GNUTLS_SHUT_WR);
+
+      end:
+
+	close(fd);
+
+	gnutls_deinit(session);
+
+	gnutls_anon_free_client_credentials(anoncred);
+	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, const char *prio, size_t pad)
+{
+	int ret;
+	char buffer[MAX_BUF + 1];
+	gnutls_session_t session;
+	gnutls_anon_server_credentials_t anoncred;
+	gnutls_certificate_credentials_t x509_cred;
+	size_t expected;
+
+	/* 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_anon_allocate_server_credentials(&anoncred);
+
+	gnutls_init(&session, GNUTLS_SERVER);
+
+	/* avoid calling all the priority functions, since the defaults
+	 * are adequate.
+	 */
+	gnutls_priority_set_direct(session, prio, NULL);
+
+	gnutls_credentials_set(session, GNUTLS_CRD_ANON, anoncred);
+	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) {
+		close(fd);
+		gnutls_deinit(session);
+		fail("server: Handshake has failed (%s)\n\n",
+		     gnutls_strerror(ret));
+		terminate();
+	}
+	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)));
+
+	gnutls_transport_set_push_function(session, push);
+
+	total = 0;
+	do {
+		ret =
+		    gnutls_record_send2(session, buffer,
+					sizeof(buffer),
+					pad, 0);
+	} while (ret == GNUTLS_E_AGAIN
+		 || ret == GNUTLS_E_INTERRUPTED);
+
+	if (ret < 0) {
+		fail("Error sending packet: %s\n",
+		     gnutls_strerror(ret));
+		terminate();
+	}
+
+	expected = sizeof(buffer) + pad + gnutls_record_overhead_size(session);
+	if (total != expected) {
+		fail("Sent data (%u) are lower than expected (%u)\n",
+		     (unsigned) total, (unsigned) expected);
+		terminate();
+	}
+
+	/* do not wait for the peer to close the connection.
+	 */
+	gnutls_bye(session, GNUTLS_SHUT_WR);
+
+	close(fd);
+	gnutls_deinit(session);
+
+	gnutls_anon_free_server_credentials(anoncred);
+	gnutls_certificate_free_credentials(x509_cred);
+
+	gnutls_global_deinit();
+
+	if (debug)
+		success("server: finished\n");
+}
+
+static void start(const char *prio, size_t pad)
+{
+	int fd[2];
+	int ret;
+
+	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], prio, pad);
+		kill(child, SIGTERM);
+	} else {
+		close(fd[0]);
+		client(fd[1], prio);
+		exit(0);
+	}
+}
+
+#define AES_GCM "NONE:+VERS-TLS1.3:+AES-256-GCM:+AEAD:+SIGN-ALL:+GROUP-ALL"
+
+static void ch_handler(int sig)
+{
+	int status;
+	wait(&status);
+	check_wait_status(status);
+	return;
+}
+
+void doit(void)
+{
+	signal(SIGCHLD, ch_handler);
+
+	start(AES_GCM, HIGH(MAX_BUF+1)-(MAX_BUF+1));
+	start(AES_GCM, 0);
+	start(AES_GCM, 1);
+}
+
+#endif				/* _WIN32 */