/*
 * Copyright (C) Andreas Schneider 2013 <asn@samba.org>
 *
 * All rights reserved.
 *
 * 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. Neither the name of the author nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
 */

#include "config.h"

#include "torture.h"

#include <errno.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <signal.h>
#include <fcntl.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <time.h>
#include <stdbool.h>

#define TORTURE_DNS_SRV_IPV4 "127.0.0.10"
/* socket wrapper IPv6 prefix  fd00::5357:5fxx */
#define TORTURE_DNS_SRV_IPV6 "fd00::5357:5f0a"
#define TORTURE_DNS_SRV_PORT 53

#define TORTURE_SOCKET_DIR "/tmp/test_resolv_wrapper_XXXXXX"
#define TORTURE_DNS_SRV_PIDFILE "dns_srv.pid"
#define TORTURE_PCAP_FILE "socket_trace.pcap"

#define RWRAP_RESOLV_CONF_TMPL "rwrap_resolv_conf_XXXXXX"

const char *torture_server_address(int family)
{
	switch (family) {
	case AF_INET: {
		const char *ip4 = getenv("TORTURE_SERVER_ADDRESS_IPV4");

		if (ip4 != NULL && ip4[0] != '\0') {
			return ip4;
		}

		return TORTURE_DNS_SRV_IPV4;
	}
#ifdef HAVE_IPV6
	case AF_INET6: {
		const char *ip6 = getenv("TORTURE_SERVER_ADDRESS_IPV6");

		if (ip6 != NULL && ip6[0] != '\0') {
			return ip6;
		}

		return TORTURE_DNS_SRV_IPV6;
	}
#endif
	default:
		return NULL;
	}

	return NULL;
}

int torture_server_port(void)
{
	char *env = getenv("TORTURE_SERVER_PORT");

	if (env != NULL && env[0] != '\0' && strlen(env) < 6) {
		int port = atoi(env);

		if (port > 0 && port < 65536) {
			return port;
		}
	}

	return TORTURE_DNS_SRV_PORT;
}

void torture_setup_socket_dir(void **state)
{
	struct torture_state *s;
	const char *p;
	size_t len;

	s = malloc(sizeof(struct torture_state));
	assert_non_null(s);

	s->socket_dir = strdup(TORTURE_SOCKET_DIR);
	assert_non_null(s->socket_dir);

	p = mkdtemp(s->socket_dir);
	assert_non_null(p);

	/* pcap file */
	len = strlen(p) + 1 + strlen(TORTURE_PCAP_FILE) + 1;

	s->pcap_file = malloc(len);
	assert_non_null(s->pcap_file);

	snprintf(s->pcap_file, len, "%s/%s", p, TORTURE_PCAP_FILE);

	/* pid file */
	len = strlen(p) + 1 + strlen(TORTURE_DNS_SRV_PIDFILE) + 1;

	s->srv_pidfile = malloc(len);
	assert_non_null(s->srv_pidfile);

	snprintf(s->srv_pidfile, len, "%s/%s", p, TORTURE_DNS_SRV_PIDFILE);

	setenv("SOCKET_WRAPPER_DIR", p, 1);
	setenv("SOCKET_WRAPPER_DEFAULT_IFACE", "170", 1);
	setenv("SOCKET_WRAPPER_PCAP_FILE", s->pcap_file, 1);

	*state = s;
}

const char *torture_server_resolv_conf(void **state)
{
	struct torture_state *s = (struct torture_state *) *state;
	if (s == NULL) {
		return NULL;
	}
	return s->resolv_conf;
}

static char *torture_setup_resolv_conf(const char **nameservers, size_t num_ns)
{
	char *path;
	int rc_fd;
	FILE *resolv_conf;
	size_t i;

	path = strdup(RWRAP_RESOLV_CONF_TMPL);
	assert_non_null(path);
	rc_fd = mkstemp(path);
	assert_return_code(rc_fd, errno);
	assert_non_null(path);
	resolv_conf = fdopen(rc_fd, "a");
	assert_non_null(resolv_conf);

	for (i = 0; i < num_ns; i++) {
		fputs("nameserver ", resolv_conf);
		fputs(nameservers[i], resolv_conf);
		fputs("\n", resolv_conf);
	}
	fflush(resolv_conf);

	fclose(resolv_conf);
	close(rc_fd);
	return path;
}

static void torture_teardown_resolv_conf(char *resolv_conf_path)
{
	unlink(resolv_conf_path);
	free(resolv_conf_path);
}

static void torture_setup_dns_srv_ip(void **state,
				     int family,
				     const char *ip,
				     int port)
{
	struct torture_state *s;
	char start_dns_srv[1024] = {0};
	int count = 0;
	int rc;
	const char *nameservers[1] = {
	    torture_server_address(family),
	};

	torture_setup_socket_dir(state);

	s = (struct torture_state *) *state;

	/* set default iface for the server */
	setenv("SOCKET_WRAPPER_DEFAULT_IFACE", "10", 1);

	snprintf(start_dns_srv, sizeof(start_dns_srv),
		 "%s/tests/dns_srv -b %s -p %d -D --pid %s",
		 BINARYDIR, ip, port, s->srv_pidfile);

	rc = system(start_dns_srv);
	assert_int_equal(rc, 0);

	do {
		struct stat sb;

		count++;
		if (count > 100) {
			break;
		}

		rc = stat(s->srv_pidfile, &sb);
		/* Wait 200 ms before retrying */
		usleep(200 * 1000);
	} while (rc != 0);
	assert_int_equal(rc, 0);

	/* set default iface for the client */
	setenv("SOCKET_WRAPPER_DEFAULT_IFACE", "170", 1);

	/* write a resolv.conf for the client */
	s->resolv_conf = torture_setup_resolv_conf(nameservers, 1);
}

void torture_setup_dns_srv_ipv4(void **state)
{
	torture_setup_dns_srv_ip(state,
				 AF_INET,
				 "0.0.0.0",
				 torture_server_port());
}

void torture_setup_dns_srv_ipv6(void **state)
{
	torture_setup_dns_srv_ip(state,
				 AF_INET6,
				 "::",
				 torture_server_port());
}

void torture_teardown_socket_dir(void **state)
{
	struct torture_state *s = (struct torture_state *) *state;
	char *env = getenv("TORTURE_SKIP_CLEANUP");
	char remove_cmd[1024] = {0};
	int rc;

	if (env != NULL && env[0] == '1') {
		fprintf(stderr, ">>> Skipping cleanup of %s", s->socket_dir);
	} else {
		snprintf(remove_cmd, sizeof(remove_cmd), "rm -rf %s", s->socket_dir);

		rc = system(remove_cmd);
		if (rc < 0) {
			fprintf(stderr, "%s failed: %s", remove_cmd, strerror(errno));
		}
	}

	free(s->socket_dir);
	free(s->pcap_file);
	free(s->srv_pidfile);
	free(s);
}

void torture_teardown_dns_srv(void **state)
{
	struct torture_state *s = (struct torture_state *) *state;
	char buf[8] = {0};
	long int tmp;
	ssize_t rc;
	pid_t pid;
	int fd;
	bool is_running = true;
	int count;

	/* read the pidfile */
	fd = open(s->srv_pidfile, O_RDONLY);
	if (fd < 0) {
		goto done;
	}

	rc = read(fd, buf, sizeof(buf));
	close(fd);
	if (rc <= 0) {
		goto done;
	}

	buf[sizeof(buf) - 1] = '\0';

	tmp = strtol(buf, NULL, 10);
	if (tmp == 0 || tmp > 0xFFFF || errno == ERANGE) {
		goto done;
	}

	pid = (pid_t)(tmp & 0xFFFF);

	/* Make sure the daemon goes away! */
	for (count = 0; count < 10; count++) {
		kill(pid, SIGTERM);

		usleep(200);

		rc = kill(pid, 0);
		if (rc != 0) {
			is_running = false;
			break;
		}
	}

	if (is_running) {
		fprintf(stderr,
			"WARNING the DNS server is still running!\n");
	}

done:
	torture_teardown_resolv_conf(s->resolv_conf);
	torture_teardown_socket_dir(state);
}

void torture_generate_random_buffer(uint8_t *out, int len)
{
	int i;

	srand(time(NULL));

	for (i = 0; i < len; i++) {
		out[i] = (uint8_t)rand();
	}
}