/*

 * 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 <https://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/crypto.h>

#include <gnutls/dtls.h>

#include <signal.h>

#include <assert.h>

#include "cert-common.h"

#include "utils.h"

#include "virt-time.h"

#define MIN(x,y) (((x)<(y))?(x):(y))

/* 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.

 */

#define SESSIONS 3

#define MAX_BUF 1024

#define MSG "Hello TLS"

#define EARLY_MSG "Hello TLS, it's early"

#define PRIORITY "NORMAL:-VERS-ALL:+VERS-TLS1.3"

static const

gnutls_datum_t hrnd = {(void*)"\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 32};

static int gnutls_rnd_works;

int __attribute__ ((visibility ("protected")))

gnutls_rnd(gnutls_rnd_level_t level, void *data, size_t len)

{

	gnutls_rnd_works = 1;

	memset(data, 0xff, len);

	/* Flip the first byte to avoid infinite loop in the RSA

	 * blinding code of Nettle */

	if (len > 0)

		memset(data, 0x0, 1);

	return 0;

}

static void client(int sds[], const char *data, size_t size, size_t maxsize)

{

	int ret;

	char buffer[MAX_BUF + 1];

	gnutls_certificate_credentials_t x509_cred;

	gnutls_session_t session;

	int t;

	gnutls_datum_t session_data = {NULL, 0};

	if (debug) {

		gnutls_global_set_log_function(client_log_func);

		gnutls_global_set_log_level(7);

	}

	/* Generate the same ob_ticket_age value, which affects the

	 * binder calculation.

	 */

	virt_time_init();

	gnutls_certificate_allocate_credentials(&x509_cred);

	for (t = 0; t < SESSIONS; t++) {

		int sd = sds[t];

		assert(gnutls_init(&session, GNUTLS_CLIENT)>=0);

		assert(gnutls_priority_set_direct(session, PRIORITY, NULL)>=0);

		gnutls_credentials_set(session, GNUTLS_CRD_CERTIFICATE, x509_cred);

		gnutls_transport_set_int(session, sd);

		if (t > 0) {

			assert(gnutls_session_set_data(session, session_data.data, session_data.size) >= 0);

			/* The server should have advertised the same maximum. */

			if (gnutls_record_get_max_early_data_size(session) != maxsize)

				fail("client: max_early_data_size mismatch %d != %d\n",

				     (int) gnutls_record_get_max_early_data_size(session),

				     (int) maxsize);

			assert(gnutls_record_send_early_data(session, data, MIN(size, maxsize)) >= 0);

			assert(gnutls_handshake_set_random(session, &hrnd) >= 0);

		}

		/* Perform the TLS handshake

		 */

		gnutls_handshake_set_timeout(session, 20 * 1000);

		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 (t == 0) {

			/* get the session data size */

			ret =

			    gnutls_session_get_data2(session,

						     &session_data);

			if (ret < 0)

				fail("client: Getting resume data failed\n");

		}

		if (t > 0) {

			if (!gnutls_session_is_resumed(session)) {

				fail("client: session_is_resumed error (%d)\n", t);

			}

		}

		gnutls_record_send(session, MSG, strlen(MSG));

		do {

			ret = gnutls_record_recv(session, buffer, sizeof(buffer));

		} while (ret == GNUTLS_E_AGAIN);

		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));

			goto end;

		}

		gnutls_bye(session, GNUTLS_SHUT_WR);

		close(sd);

		gnutls_deinit(session);

	}

 end:

	gnutls_free(session_data.data);

	gnutls_certificate_free_credentials(x509_cred);

}

static pid_t child;

#define MAX_CLIENT_HELLO_RECORDED 10

struct storage_st {

	gnutls_datum_t entries[MAX_CLIENT_HELLO_RECORDED];

	size_t num_entries;

};

static int

storage_add(void *ptr, time_t expires, const gnutls_datum_t *key, const gnutls_datum_t *value)

{

	struct storage_st *storage = ptr;

	gnutls_datum_t *datum;

	size_t i;

	for (i = 0; i < storage->num_entries; i++) {

		if (key->size == storage->entries[i].size &&

		    memcmp(storage->entries[i].data, key->data, key->size) == 0) {

			return GNUTLS_E_DB_ENTRY_EXISTS;

		}

	}

	/* If the maximum number of ClientHello exceeded, reject early

	 * data until next time.

	 */

	if (storage->num_entries == MAX_CLIENT_HELLO_RECORDED)

		return GNUTLS_E_DB_ERROR;

	datum = &storage->entries[storage->num_entries];

	datum->data = gnutls_malloc(key->size);

	if (!datum->data)

		return GNUTLS_E_MEMORY_ERROR;

	memcpy(datum->data, key->data, key->size);

	datum->size = key->size;

	storage->num_entries++;

	return 0;

}

static void

storage_clear(struct storage_st *storage)

{

	size_t i;

	for (i = 0; i < storage->num_entries; i++)

		gnutls_free(storage->entries[i].data);

	storage->num_entries = 0;

}

static void server(int sds[], const char *data, size_t size, size_t maxsize)

{

	int ret;

	char buffer[MAX_BUF + 1];

	gnutls_session_t session;

	gnutls_certificate_credentials_t x509_cred;

	gnutls_datum_t session_ticket_key = { NULL, 0 };

	struct storage_st storage;

	gnutls_anti_replay_t anti_replay;

	int t;

	/* this must be called once in the program

	 */

	global_init();

	memset(buffer, 0, sizeof(buffer));

	memset(&storage, 0, sizeof(storage));

	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_session_ticket_key_generate(&session_ticket_key);

	ret = gnutls_anti_replay_init(&anti_replay);

	if (ret < 0)

		fail("server: failed to initialize anti-replay\n");

	gnutls_anti_replay_set_add_function(anti_replay, storage_add);

	gnutls_anti_replay_set_ptr(anti_replay, &storage);

	for (t = 0; t < SESSIONS; t++) {

		int sd = sds[t];

		assert(gnutls_init(&session, GNUTLS_SERVER|GNUTLS_ENABLE_EARLY_DATA)>=0);

		assert(gnutls_priority_set_direct(session, PRIORITY, NULL)>=0);

		gnutls_credentials_set(session, GNUTLS_CRD_CERTIFICATE, x509_cred);

		gnutls_session_ticket_enable_server(session,

						    &session_ticket_key);

		gnutls_anti_replay_enable(session, anti_replay);

		/* on the replay connection, early data is skipped

		 * until max_early_data_size without decryption

		 */

		if (t < 2)

			(void) gnutls_record_set_max_early_data_size(session, maxsize);

		gnutls_transport_set_int(session, sd);

		do {

			ret = gnutls_handshake(session);

		}

		while (ret < 0 && gnutls_error_is_fatal(ret) == 0);

		if (ret < 0) {

			close(sd);

			gnutls_deinit(session);

			fail("server: Handshake has failed (%s)\n\n",

			     gnutls_strerror(ret));

			return;

		}

		if (debug)

			success("server: Handshake was completed\n");

		if (t > 0) {

			if (!gnutls_session_is_resumed(session)) {

				fail("server: session_is_resumed error (%d)\n", t);

			}

			/* as we reuse the same ticket twice, expect

			 * early data only on the first resumption */

			if (t == 1) {

				if (gnutls_rnd_works) {

					if (!(gnutls_session_get_flags(session) & GNUTLS_SFLAGS_EARLY_DATA)) {

						fail("server: early data is not received (%d)\n", t);

					}

				} else {

					success("server: gnutls_rnd() could not be overridden, skip checking replay (%d)\n", t);

				}

				ret = gnutls_record_recv_early_data(session, buffer, sizeof(buffer));

				if (ret < 0) {

					fail("server: failed to retrieve early data: %s\n",

					     gnutls_strerror(ret));

				}

				if ((size_t) ret != MIN(size, maxsize) ||

				    memcmp(buffer, data, ret))

					fail("server: early data mismatch\n");

			} else {

				if (gnutls_rnd_works) {

					if (gnutls_session_get_flags(session) & GNUTLS_SFLAGS_EARLY_DATA) {

						fail("server: early data is not rejected (%d)\n", t);

					}

				} else {

					success("server: gnutls_rnd() could not be overridden, skip checking replay (%d)\n", t);

				}

			}

		}

		/* see the Getting peer's information example */

		/* print_info(session); */

		for (;;) {

			memset(buffer, 0, MAX_BUF + 1);

			ret = gnutls_record_recv(session, buffer, MAX_BUF);

			if (ret == 0) {

				if (debug)

					success

					    ("server: Peer has closed the GnuTLS connection\n");

				break;

			} else if (ret < 0) {

				kill(child, SIGTERM);

				fail("server: Received corrupted data(%d). Closing...\n", ret);

				break;

			} else if (ret > 0) {

				/* echo data back to the client

				 */

				gnutls_record_send(session, buffer,

						   strlen(buffer));

			}

		}

		/* do not wait for the peer to close the connection.

		 */

		gnutls_bye(session, GNUTLS_SHUT_WR);

		close(sd);

		gnutls_deinit(session);

	}

	gnutls_anti_replay_deinit(anti_replay);

	storage_clear(&storage);

	gnutls_free(session_ticket_key.data);

	gnutls_certificate_free_credentials(x509_cred);

	if (debug)

		success("server: finished\n");

}

static void

start(const char *data, size_t size, size_t maxsize)

{

	int client_sds[SESSIONS], server_sds[SESSIONS];

	int i;

	int ret;

	signal(SIGCHLD, SIG_IGN);

	signal(SIGPIPE, SIG_IGN);

	for (i = 0; i < SESSIONS; i++) {

		int sockets[2];

		ret = socketpair(AF_UNIX, SOCK_STREAM, 0, sockets);

		if (ret < 0) {

			perror("socketpair");

			exit(1);

		}

		server_sds[i] = sockets[0];

		client_sds[i] = sockets[1];

	}

	child = fork();

	if (child < 0) {

		perror("fork");

		fail("fork");

		exit(1);

	}

	if (child) {

		/* parent */

		for (i = 0; i < SESSIONS; i++)

			close(client_sds[i]);

		server(server_sds, data, size, maxsize);

		kill(child, SIGTERM);

	} else {

		for (i = 0; i < SESSIONS; i++)

			close(server_sds[i]);

		client(client_sds, data, size, maxsize);

		exit(0);

	}

}

void doit(void)

{

	start(EARLY_MSG, sizeof(EARLY_MSG), MAX_BUF);

	start(EARLY_MSG, sizeof(EARLY_MSG), 10);

}

#endif				/* _WIN32 */