/*
 * Copyright (c) 2009-2012 Niels Provos and Nick Mathewson
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifdef WIN32
#include <winsock2.h>
#include <windows.h>
#endif

#ifndef WIN32
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#endif

#include "event2/util.h"
#include "event2/event.h"
#include "event2/bufferevent_ssl.h"
#include "event2/buffer.h"
#include "event2/listener.h"

#include "regress.h"
#include "tinytest.h"
#include "tinytest_macros.h"

#include <openssl/ssl.h>
#include <openssl/bio.h>
#include <openssl/err.h>
#include <openssl/pem.h>

#include <string.h>

/* A short pre-generated key, to save the cost of doing an RSA key generation
 * step during the unit tests.  It's only 512 bits long, and it is published
 * in this file, so you would have to be very foolish to consider using it in
 * your own code. */
static const char KEY[] =
    "-----BEGIN RSA PRIVATE KEY-----\n"
    "MIIBOgIBAAJBAKibTEzXjj+sqpipePX1lEk5BNFuL/dDBbw8QCXgaJWikOiKHeJq\n"
    "3FQ0OmCnmpkdsPFE4x3ojYmmdgE2i0dJwq0CAwEAAQJAZ08gpUS+qE1IClps/2gG\n"
    "AAer6Bc31K2AaiIQvCSQcH440cp062QtWMC3V5sEoWmdLsbAHFH26/9ZHn5zAflp\n"
    "gQIhANWOx/UYeR8HD0WREU5kcuSzgzNLwUErHLzxP7U6aojpAiEAyh2H35CjN/P7\n"
    "NhcZ4QYw3PeUWpqgJnaE/4i80BSYkSUCIQDLHFhLYLJZ80HwHTADif/ISn9/Ow6b\n"
    "p6BWh3DbMar/eQIgBPS6azH5vpp983KXkNv9AL4VZi9ac/b+BeINdzC6GP0CIDmB\n"
    "U6GFEQTZ3IfuiVabG5pummdC4DNbcdI+WKrSFNmQ\n"
    "-----END RSA PRIVATE KEY-----\n";

static EVP_PKEY *
getkey(void)
{
	EVP_PKEY *key;
	BIO *bio;

	/* new read-only BIO backed by KEY. */
	bio = BIO_new_mem_buf((char*)KEY, -1);
	tt_assert(bio);

	key = PEM_read_bio_PrivateKey(bio,NULL,NULL,NULL);
	BIO_free(bio);
	tt_assert(key);

	return key;
end:
	return NULL;
}

static X509 *
getcert(void)
{
	/* Dummy code to make a quick-and-dirty valid certificate with
	   OpenSSL.  Don't copy this code into your own program! It does a
	   number of things in a stupid and insecure way. */
	X509 *x509 = NULL;
	X509_NAME *name = NULL;
	EVP_PKEY *key = getkey();
	int nid;
	time_t now = time(NULL);

	tt_assert(key);

	x509 = X509_new();
	tt_assert(x509);
	tt_assert(0 != X509_set_version(x509, 2));
	tt_assert(0 != ASN1_INTEGER_set(X509_get_serialNumber(x509),
		(long)now));

	name = X509_NAME_new();
	tt_assert(name);
	nid = OBJ_txt2nid("commonName");
	tt_assert(NID_undef != nid);
	tt_assert(0 != X509_NAME_add_entry_by_NID(
		    name, nid, MBSTRING_ASC, (unsigned char*)"example.com",
		    -1, -1, 0));

	X509_set_subject_name(x509, name);
	X509_set_issuer_name(x509, name);

	X509_time_adj(X509_get_notBefore(x509), 0, &now);
	now += 3600;
	X509_time_adj(X509_get_notAfter(x509), 0, &now);
	X509_set_pubkey(x509, key);
	tt_assert(0 != X509_sign(x509, key, EVP_sha1()));

	return x509;
end:
	X509_free(x509);
	return NULL;
}

static int disable_tls_11_and_12 = 0;
static SSL_CTX *the_ssl_ctx = NULL;

static SSL_CTX *
get_ssl_ctx(void)
{
	if (the_ssl_ctx)
		return the_ssl_ctx;
	the_ssl_ctx = SSL_CTX_new(SSLv23_method());
	if (!the_ssl_ctx)
		return NULL;
	if (disable_tls_11_and_12) {
#ifdef SSL_OP_NO_TLSv1_2
		SSL_CTX_set_options(the_ssl_ctx, SSL_OP_NO_TLSv1_2);
#endif
#ifdef SSL_OP_NO_TLSv1_1
		SSL_CTX_set_options(the_ssl_ctx, SSL_OP_NO_TLSv1_1);
#endif
	}
	return the_ssl_ctx;
}

static void
init_ssl(void)
{
	SSL_library_init();
	ERR_load_crypto_strings();
	SSL_load_error_strings();
	OpenSSL_add_all_algorithms();
	if (SSLeay() != OPENSSL_VERSION_NUMBER) {
		TT_DECLARE("WARN", ("Version mismatch for openssl: compiled with %lx but running with %lx", (unsigned long)OPENSSL_VERSION_NUMBER, (unsigned long)SSLeay()));
	}
}

/* ====================
   Here's a simple test: we read a number from the input, increment it, and
   reply, until we get to 1001.
*/

static int test_is_done = 0;
static int n_connected = 0;
static int got_close = 0;
static int got_error = 0;
static int renegotiate_at = -1;
static int stop_when_connected = 0;
static int pending_connect_events = 0;
static struct event_base *exit_base = NULL;

static void
respond_to_number(struct bufferevent *bev, void *ctx)
{
	struct evbuffer *b = bufferevent_get_input(bev);
	char *line;
	int n;
	line = evbuffer_readln(b, NULL, EVBUFFER_EOL_LF);
	if (! line)
		return;
	n = atoi(line);
	if (n <= 0)
		TT_FAIL(("Bad number: %s", line));
	TT_BLATHER(("The number was %d", n));
	if (n == 1001) {
		++test_is_done;
		bufferevent_free(bev); /* Should trigger close on other side. */
		return;
	}
	if (!strcmp(ctx, "client") && n == renegotiate_at) {
		SSL_renegotiate(bufferevent_openssl_get_ssl(bev));
	}
	++n;
	evbuffer_add_printf(bufferevent_get_output(bev),
	    "%d\n", n);
	TT_BLATHER(("Done reading; now writing."));
	bufferevent_enable(bev, EV_WRITE);
	bufferevent_disable(bev, EV_READ);
}

static void
done_writing_cb(struct bufferevent *bev, void *ctx)
{
	struct evbuffer *b = bufferevent_get_output(bev);
	if (evbuffer_get_length(b))
		return;
	TT_BLATHER(("Done writing."));
	bufferevent_disable(bev, EV_WRITE);
	bufferevent_enable(bev, EV_READ);
}

static void
eventcb(struct bufferevent *bev, short what, void *ctx)
{
	TT_BLATHER(("Got event %d", (int)what));
	if (what & BEV_EVENT_CONNECTED) {
		SSL *ssl;
		X509 *peer_cert;
		++n_connected;
		ssl = bufferevent_openssl_get_ssl(bev);
		tt_assert(ssl);
		peer_cert = SSL_get_peer_certificate(ssl);
		if (0==strcmp(ctx, "server")) {
			tt_assert(peer_cert == NULL);
		} else {
			tt_assert(peer_cert != NULL);
		}
		if (stop_when_connected) {
			if (--pending_connect_events == 0)
				event_base_loopexit(exit_base, NULL);
		}
	} else if (what & BEV_EVENT_EOF) {
		TT_BLATHER(("Got a good EOF"));
		++got_close;
		bufferevent_free(bev);
	} else if (what & BEV_EVENT_ERROR) {
		TT_BLATHER(("Got an error."));
		++got_error;
		bufferevent_free(bev);
	}
end:
	;
}

static void
open_ssl_bufevs(struct bufferevent **bev1_out, struct bufferevent **bev2_out,
    struct event_base *base, int is_open, int flags, SSL *ssl1, SSL *ssl2,
    evutil_socket_t *fd_pair, struct bufferevent **underlying_pair)
{
	int state1 = is_open ? BUFFEREVENT_SSL_OPEN :BUFFEREVENT_SSL_CONNECTING;
	int state2 = is_open ? BUFFEREVENT_SSL_OPEN :BUFFEREVENT_SSL_ACCEPTING;
	if (fd_pair) {
		*bev1_out = bufferevent_openssl_socket_new(
			base, fd_pair[0], ssl1, state1, flags);
		*bev2_out = bufferevent_openssl_socket_new(
			base, fd_pair[1], ssl2, state2, flags);
	} else {
		*bev1_out = bufferevent_openssl_filter_new(
			base, underlying_pair[0], ssl1, state1, flags);
		*bev2_out = bufferevent_openssl_filter_new(
			base, underlying_pair[1], ssl2, state2, flags);

	}
	bufferevent_setcb(*bev1_out, respond_to_number, done_writing_cb,
	    eventcb, (void*)"client");
	bufferevent_setcb(*bev2_out, respond_to_number, done_writing_cb,
	    eventcb, (void*)"server");
}

static void
regress_bufferevent_openssl(void *arg)
{
	struct basic_test_data *data = arg;

	struct bufferevent *bev1, *bev2;
	SSL *ssl1, *ssl2;
	X509 *cert = getcert();
	EVP_PKEY *key = getkey();
	const int start_open = strstr((char*)data->setup_data, "open")!=NULL;
	const int filter = strstr((char*)data->setup_data, "filter")!=NULL;
	int flags = BEV_OPT_DEFER_CALLBACKS;
	struct bufferevent *bev_ll[2] = { NULL, NULL };
	evutil_socket_t *fd_pair = NULL;

	tt_assert(cert);
	tt_assert(key);

	init_ssl();

	if (strstr((char*)data->setup_data, "renegotiate")) {
		if (SSLeay() >= 0x10001000 &&
		    SSLeay() <  0x1000104f) {
			/* 1.0.1 up to 1.0.1c has a bug where TLS1.1 and 1.2
			 * can't renegotiate with themselves. Disable. */
			disable_tls_11_and_12 = 1;
		}
		renegotiate_at = 600;
	}

	ssl1 = SSL_new(get_ssl_ctx());
	ssl2 = SSL_new(get_ssl_ctx());

	SSL_use_certificate(ssl2, cert);
	SSL_use_PrivateKey(ssl2, key);

	if (! start_open)
		flags |= BEV_OPT_CLOSE_ON_FREE;

	if (!filter) {
		tt_assert(strstr((char*)data->setup_data, "socketpair"));
		fd_pair = data->pair;
	} else {
		bev_ll[0] = bufferevent_socket_new(data->base, data->pair[0],
		    BEV_OPT_CLOSE_ON_FREE);
		bev_ll[1] = bufferevent_socket_new(data->base, data->pair[1],
		    BEV_OPT_CLOSE_ON_FREE);
	}

	open_ssl_bufevs(&bev1, &bev2, data->base, 0, flags, ssl1, ssl2,
	    fd_pair, bev_ll);

	if (!filter) {
		tt_int_op(bufferevent_getfd(bev1), ==, data->pair[0]);
	} else {
		tt_ptr_op(bufferevent_get_underlying(bev1), ==, bev_ll[0]);
	}

	if (start_open) {
		pending_connect_events = 2;
		stop_when_connected = 1;
		exit_base = data->base;
		event_base_dispatch(data->base);
		/* Okay, now the renegotiation is done.  Make new
		 * bufferevents to test opening in BUFFEREVENT_SSL_OPEN */
		flags |= BEV_OPT_CLOSE_ON_FREE;
		bufferevent_free(bev1);
		bufferevent_free(bev2);
		bev1 = bev2 = NULL;
		open_ssl_bufevs(&bev1, &bev2, data->base, 1, flags, ssl1, ssl2,
		    fd_pair, bev_ll);
	}

	bufferevent_enable(bev1, EV_READ|EV_WRITE);
	bufferevent_enable(bev2, EV_READ|EV_WRITE);

	evbuffer_add_printf(bufferevent_get_output(bev1), "1\n");

	event_base_dispatch(data->base);

	tt_assert(test_is_done == 1);
	tt_assert(n_connected == 2);

	/* We don't handle shutdown properly yet.
	   tt_int_op(got_close, ==, 1);
	   tt_int_op(got_error, ==, 0);
	*/
end:
	return;
}

static void
acceptcb(struct evconnlistener *listener, evutil_socket_t fd,
    struct sockaddr *addr, int socklen, void *arg)
{
	struct basic_test_data *data = arg;
	struct bufferevent *bev;
	SSL *ssl = SSL_new(get_ssl_ctx());

	SSL_use_certificate(ssl, getcert());
	SSL_use_PrivateKey(ssl, getkey());

	bev = bufferevent_openssl_socket_new(
		data->base,
		fd,
		ssl,
		BUFFEREVENT_SSL_ACCEPTING,
		BEV_OPT_CLOSE_ON_FREE|BEV_OPT_DEFER_CALLBACKS);

	bufferevent_setcb(bev, respond_to_number, NULL, eventcb,
	    (void*)"server");

	bufferevent_enable(bev, EV_READ|EV_WRITE);

	/* Only accept once, then disable ourself. */
	evconnlistener_disable(listener);
}

static void
regress_bufferevent_openssl_connect(void *arg)
{
	struct basic_test_data *data = arg;

	struct event_base *base = data->base;

	struct evconnlistener *listener;
	struct bufferevent *bev;
	struct sockaddr_in sin;
	struct sockaddr_storage ss;
	ev_socklen_t slen;

	init_ssl();

	memset(&sin, 0, sizeof(sin));
	sin.sin_family = AF_INET;
	sin.sin_addr.s_addr = htonl(0x7f000001);

	memset(&ss, 0, sizeof(ss));
	slen = sizeof(ss);

	listener = evconnlistener_new_bind(base, acceptcb, data,
	    LEV_OPT_CLOSE_ON_FREE|LEV_OPT_REUSEABLE,
	    -1, (struct sockaddr *)&sin, sizeof(sin));

	tt_assert(listener);
	tt_assert(evconnlistener_get_fd(listener) >= 0);

	bev = bufferevent_openssl_socket_new(
		data->base, -1, SSL_new(get_ssl_ctx()),
		BUFFEREVENT_SSL_CONNECTING,
		BEV_OPT_CLOSE_ON_FREE|BEV_OPT_DEFER_CALLBACKS);
	tt_assert(bev);

	bufferevent_setcb(bev, respond_to_number, NULL, eventcb,
	    (void*)"client");

	tt_assert(getsockname(evconnlistener_get_fd(listener),
		(struct sockaddr*)&ss, &slen) == 0);
	tt_assert(slen == sizeof(struct sockaddr_in));
	tt_int_op(((struct sockaddr*)&ss)->sa_family, ==, AF_INET);
	tt_int_op(((struct sockaddr*)&ss)->sa_family, ==, AF_INET);

	tt_assert(0 ==
	    bufferevent_socket_connect(bev, (struct sockaddr*)&ss, slen));
	evbuffer_add_printf(bufferevent_get_output(bev), "1\n");
	bufferevent_enable(bev, EV_READ|EV_WRITE);

	event_base_dispatch(base);
end:
	;
}

struct testcase_t ssl_testcases[] = {

	{ "bufferevent_socketpair", regress_bufferevent_openssl, TT_ISOLATED,
	  &basic_setup, (void*)"socketpair" },
	{ "bufferevent_filter", regress_bufferevent_openssl,
	  TT_ISOLATED,
	  &basic_setup, (void*)"filter" },
	{ "bufferevent_renegotiate_socketpair", regress_bufferevent_openssl,
	  TT_ISOLATED,
	  &basic_setup, (void*)"socketpair renegotiate" },
	{ "bufferevent_renegotiate_filter", regress_bufferevent_openssl,
	  TT_ISOLATED,
	  &basic_setup, (void*)"filter renegotiate" },
	{ "bufferevent_socketpair_startopen", regress_bufferevent_openssl,
	  TT_ISOLATED, &basic_setup, (void*)"socketpair open" },
	{ "bufferevent_filter_startopen", regress_bufferevent_openssl,
	  TT_ISOLATED, &basic_setup, (void*)"filter open" },

	{ "bufferevent_connect", regress_bufferevent_openssl_connect,
	  TT_FORK|TT_NEED_BASE, &basic_setup, NULL },

	END_OF_TESTCASES,
};