test: add test cases

2023-03-26 00:27:40 +08:00
parent 56d711a796
commit c90a85dfc7
25 changed files with 1177 additions and 39 deletions
--- a/src/dns_client.c
+++ b/src/dns_client.c
@@ -3704,7 +3704,8 @@ int dns_client_query(const char *domain, int qtype, dns_client_callback callback
 	}
 	pthread_mutex_unlock(&client.domain_map_lock);

-	tlog(TLOG_INFO, "request: %s, qtype: %d, id: %d, group: %s", domain, qtype, query->sid, query->server_group->group_name);
+	tlog(TLOG_INFO, "request: %s, qtype: %d, id: %d, group: %s", domain, qtype, query->sid,
+		 query->server_group->group_name);
 	_dns_client_query_release(query);

 	return 0;
@@ -3829,13 +3830,18 @@ static void _dns_client_remove_all_pending_servers(void)

 static void _dns_client_add_pending_servers(void)
 {
+#ifdef TEST
+	const int delay_value = 1;
+#else
+	const int delay_value = 3;
+#endif
 	struct dns_server_pending *pending = NULL;
 	struct dns_server_pending *tmp = NULL;
-	static int delay = 0;
+	static int delay = delay_value;
 	LIST_HEAD(retry_list);

 	/* add pending server after 3 seconds */
-	if (++delay < 3) {
+	if (++delay < delay_value) {
 		return;
 	}
 	delay = 0;
--- a/src/dns_conf.c
+++ b/src/dns_conf.c
@@ -3336,6 +3336,8 @@ void dns_server_load_exit(void)
 	_config_host_table_destroy();
 	_config_qtype_soa_table_destroy();
 	_config_proxy_table_destroy();
+
+	dns_conf_server_num = 0;
 }

 static int _dns_conf_speed_check_mode_verify(void)
--- a/src/dns_server.c
+++ b/src/dns_server.c
@@ -844,9 +844,12 @@ static int _dns_rrs_add_all_best_ip(struct dns_server_post_context *context)
 				continue;
 			}

-			int ttl_range = request->ping_time + request->ping_time / 10;
-			if ((ttl_range < addr_map->ping_time) && addr_map->ping_time >= 100 && ignore_speed == 0) {
-				continue;
+			/* if ping time is larger than 5ms, check again. */
+			if (addr_map->ping_time - request->ping_time >= 50) {
+				int ttl_range = request->ping_time + request->ping_time / 10 + 5;
+				if ((ttl_range < addr_map->ping_time) && addr_map->ping_time >= 100 && ignore_speed == 0) {
+					continue;
+				}
 			}

 			context->ip_num++;
@@ -4700,7 +4703,7 @@ out:
 	return ret;
 }

-static void _dns_server_check_ipv6_ready(void)
+void dns_server_check_ipv6_ready(void)
 {
 	static int do_get_conf = 0;
 	static int is_icmp_check_set;
@@ -6231,7 +6234,7 @@ static void _dns_server_period_run_second(void)
 	_dns_server_check_need_exit();

 	if (sec % IPV6_READY_CHECK_TIME == 0 && is_ipv6_ready == 0) {
-		_dns_server_check_ipv6_ready();
+		dns_server_check_ipv6_ready();
 	}

 	if (sec % 60 == 0) {
@@ -6931,7 +6934,7 @@ int dns_server_init(void)
 		goto errout;
 	}

-	_dns_server_check_ipv6_ready();
+	dns_server_check_ipv6_ready();
 	tlog(TLOG_INFO, "%s",
 		 (is_ipv6_ready) ? "IPV6 is ready, enable IPV6 features" : "IPV6 is not ready, disable IPV6 features");

--- a/src/dns_server.h
+++ b/src/dns_server.h
@@ -37,6 +37,8 @@ struct dns_server_query_option {

 int dns_is_ipv6_ready(void);

+void dns_server_check_ipv6_ready(void);
+
 int dns_server_init(void);

 int dns_server_run(void);
--- a/src/fast_ping.c
+++ b/src/fast_ping.c
@@ -40,6 +40,7 @@
 #include <sys/eventfd.h>
 #include <sys/resource.h>
 #include <sys/socket.h>
+#include <sys/timerfd.h>
 #include <sys/types.h>
 #include <unistd.h>

@@ -95,6 +96,18 @@ struct fast_ping_packet {
 	struct fast_ping_packet_msg msg;
 };

+struct fast_ping_fake_ip {
+	struct hlist_node node;
+	atomic_t ref;
+	PING_TYPE type;
+	FAST_PING_TYPE ping_type;
+	char host[PING_MAX_HOSTLEN];
+	int ttl;
+	float time;
+	struct sockaddr_storage addr;
+	int addr_len;
+};
+
 struct ping_host_struct {
 	atomic_t ref;
 	atomic_t notified;
@@ -127,6 +140,9 @@ struct ping_host_struct {
 	};
 	socklen_t addr_len;
 	struct fast_ping_packet packet;
+
+	struct fast_ping_fake_ip *fake;
+	int fake_time_fd;
 };

 struct fast_ping_notify_event {
@@ -163,6 +179,8 @@ struct fast_ping_struct {

 	pthread_mutex_t map_lock;
 	DECLARE_HASHTABLE(addrmap, 6);
+	DECLARE_HASHTABLE(fake, 6);
+	int fake_ip_num;
 };

 static struct fast_ping_struct ping;
@@ -170,6 +188,8 @@ static atomic_t ping_sid = ATOMIC_INIT(0);
 static int bool_print_log = 1;

 static void _fast_ping_host_put(struct ping_host_struct *ping_host);
+static int _fast_ping_get_addr_by_type(PING_TYPE type, const char *ip_str, int port, struct addrinfo **out_gai,
+									   FAST_PING_TYPE *out_ping_type);

 static void _fast_ping_wakeup_thread(void)
 {
@@ -376,6 +396,179 @@ errout:
 	return -1;
 }

+static void _fast_ping_fake_put(struct fast_ping_fake_ip *fake)
+{
+	int ref_cnt = atomic_dec_and_test(&fake->ref);
+	if (!ref_cnt) {
+		if (ref_cnt < 0) {
+			tlog(TLOG_ERROR, "invalid refcount of fake ping %s", fake->host);
+			abort();
+		}
+		return;
+	}
+
+	pthread_mutex_lock(&ping.map_lock);
+	if (hash_hashed(&fake->node)) {
+		hash_del(&fake->node);
+	}
+	pthread_mutex_unlock(&ping.map_lock);
+
+	free(fake);
+}
+
+static void _fast_ping_fake_remove(struct fast_ping_fake_ip *fake)
+{
+	pthread_mutex_lock(&ping.map_lock);
+	if (hash_hashed(&fake->node)) {
+		hash_del(&fake->node);
+	}
+	pthread_mutex_unlock(&ping.map_lock);
+
+	_fast_ping_fake_put(fake);
+}
+
+static void _fast_ping_fake_get(struct fast_ping_fake_ip *fake)
+{
+	atomic_inc(&fake->ref);
+}
+
+static struct fast_ping_fake_ip *_fast_ping_fake_find(FAST_PING_TYPE ping_type, struct sockaddr *addr, int addr_len)
+{
+	struct fast_ping_fake_ip *fake = NULL;
+	struct fast_ping_fake_ip *ret = NULL;
+	uint32_t key = 0;
+
+	if (ping.fake_ip_num == 0) {
+		return NULL;
+	}
+
+	key = jhash(addr, addr_len, 0);
+	key = jhash(&ping_type, sizeof(ping_type), key);
+	pthread_mutex_lock(&ping.map_lock);
+	hash_for_each_possible(ping.fake, fake, node, key)
+	{
+		if (fake->ping_type != ping_type) {
+			continue;
+		}
+
+		if (fake->addr_len != addr_len) {
+			continue;
+		}
+
+		if (memcmp(&fake->addr, addr, fake->addr_len) != 0) {
+			continue;
+		}
+
+		ret = fake;
+		_fast_ping_fake_get(fake);
+		break;
+	}
+	pthread_mutex_unlock(&ping.map_lock);
+	return ret;
+}
+
+int fast_ping_fake_ip_add(PING_TYPE type, const char *host, int ttl, float time)
+{
+	struct fast_ping_fake_ip *fake = NULL;
+	struct fast_ping_fake_ip *fake_old = NULL;
+	char ip_str[PING_MAX_HOSTLEN];
+	int port = -1;
+	FAST_PING_TYPE ping_type = FAST_PING_END;
+	uint32_t key = 0;
+	int ret = -1;
+	struct addrinfo *gai = NULL;
+
+	if (parse_ip(host, ip_str, &port) != 0) {
+		goto errout;
+	}
+
+	ret = _fast_ping_get_addr_by_type(type, ip_str, port, &gai, &ping_type);
+	if (ret != 0) {
+		goto errout;
+	}
+
+	fake_old = _fast_ping_fake_find(ping_type, gai->ai_addr, gai->ai_addrlen);
+	fake = malloc(sizeof(*fake));
+	if (fake == NULL) {
+		goto errout;
+	}
+	memset(fake, 0, sizeof(*fake));
+
+	safe_strncpy(fake->host, ip_str, PING_MAX_HOSTLEN);
+	fake->ttl = ttl;
+	fake->time = time;
+	fake->type = type;
+	fake->ping_type = ping_type;
+	memcpy(&fake->addr, gai->ai_addr, gai->ai_addrlen);
+	fake->addr_len = gai->ai_addrlen;
+	INIT_HLIST_NODE(&fake->node);
+	atomic_set(&fake->ref, 1);
+
+	key = jhash(&fake->addr, fake->addr_len, 0);
+	key = jhash(&ping_type, sizeof(ping_type), key);
+	pthread_mutex_lock(&ping.map_lock);
+	hash_add(ping.fake, &fake->node, key);
+	pthread_mutex_unlock(&ping.map_lock);
+	ping.fake_ip_num++;
+
+	if (fake_old != NULL) {
+		_fast_ping_fake_put(fake_old);
+		_fast_ping_fake_remove(fake_old);
+	}
+
+	freeaddrinfo(gai);
+	return 0;
+errout:
+	if (fake != NULL) {
+		free(fake);
+	}
+
+	if (fake_old != NULL) {
+		_fast_ping_fake_put(fake_old);
+	}
+
+	if (gai != NULL) {
+		freeaddrinfo(gai);
+	}
+
+	return -1;
+}
+
+int fast_ping_fake_ip_remove(PING_TYPE type, const char *host)
+{
+	struct fast_ping_fake_ip *fake = NULL;
+	char ip_str[PING_MAX_HOSTLEN];
+	int port = -1;
+	int ret = -1;
+	FAST_PING_TYPE ping_type = FAST_PING_END;
+	struct addrinfo *gai = NULL;
+
+	if (parse_ip(host, ip_str, &port) != 0) {
+		return -1;
+	}
+
+	ret = _fast_ping_get_addr_by_type(type, ip_str, port, &gai, &ping_type);
+	if (ret != 0) {
+		goto errout;
+	}
+
+	fake = _fast_ping_fake_find(ping_type, gai->ai_addr, gai->ai_addrlen);
+	if (fake == NULL) {
+		goto errout;
+	}
+
+	_fast_ping_fake_remove(fake);
+	_fast_ping_fake_put(fake);
+	ping.fake_ip_num--;
+	freeaddrinfo(gai);
+	return 0;
+errout:
+	if (gai != NULL) {
+		freeaddrinfo(gai);
+	}
+	return -1;
+}
+
 static void _fast_ping_host_get(struct ping_host_struct *ping_host)
 {
 	if (atomic_inc_return(&ping_host->ref) <= 0) {
@@ -386,6 +579,15 @@ static void _fast_ping_host_get(struct ping_host_struct *ping_host)

 static void _fast_ping_close_host_sock(struct ping_host_struct *ping_host)
 {
+	if (ping_host->fake_time_fd > 0) {
+		struct epoll_event *event = NULL;
+		event = (struct epoll_event *)1;
+		epoll_ctl(ping.epoll_fd, EPOLL_CTL_DEL, ping_host->fake_time_fd, event);
+
+		close(ping_host->fake_time_fd);
+		ping_host->fake_time_fd = -1;
+	}
+
 	if (ping_host->fd < 0) {
 		return;
 	}
@@ -455,6 +657,10 @@ static void _fast_ping_host_put(struct ping_host_struct *ping_host)
 	}

 	_fast_ping_close_host_sock(ping_host);
+	if (ping_host->fake != NULL) {
+		_fast_ping_fake_put(ping_host->fake);
+		ping_host->fake = NULL;
+	}

 	pthread_mutex_lock(&ping.map_lock);
 	hash_del(&ping_host->addr_node);
@@ -546,6 +752,38 @@ errout:
 	return -1;
 }

+static int _fast_ping_send_fake(struct ping_host_struct *ping_host, struct fast_ping_fake_ip *fake)
+{
+	struct itimerspec its;
+	int sec = fake->time / 1000;
+	int cent_usec = ((long)(fake->time * 10)) % 10000;
+	its.it_value.tv_sec = sec;
+	its.it_value.tv_nsec = cent_usec * 1000 * 100;
+	its.it_interval.tv_sec = 0;
+	its.it_interval.tv_nsec = 0;
+
+	if (timerfd_settime(ping_host->fake_time_fd, 0, &its, NULL) < 0) {
+		tlog(TLOG_ERROR, "timerfd_settime failed, %s", strerror(errno));
+		goto errout;
+	}
+
+	struct epoll_event ev;
+	ev.events = EPOLLIN;
+	ev.data.ptr = ping_host;
+	if (epoll_ctl(ping.epoll_fd, EPOLL_CTL_ADD, ping_host->fake_time_fd, &ev) == -1) {
+		if (errno != EEXIST) {
+			goto errout;
+		}
+	}
+
+	ping_host->seq++;
+
+	return 0;
+
+errout:
+	return -1;
+}
+
 static int _fast_ping_sendping_v4(struct ping_host_struct *ping_host)
 {
 	struct fast_ping_packet *packet = &ping_host->packet;
@@ -710,8 +948,16 @@ errout:
 static int _fast_ping_sendping(struct ping_host_struct *ping_host)
 {
 	int ret = -1;
+	struct fast_ping_fake_ip *fake = NULL;
 	gettimeofday(&ping_host->last, NULL);

+	fake = _fast_ping_fake_find(ping_host->type, &ping_host->addr, ping_host->addr_len);
+	if (fake) {
+		ret = _fast_ping_send_fake(ping_host, fake);
+		_fast_ping_fake_put(fake);
+		return ret;
+	}
+
 	if (ping_host->type == FAST_PING_ICMP) {
 		ret = _fast_ping_sendping_v4(ping_host);
 	} else if (ping_host->type == FAST_PING_ICMP6) {
@@ -1010,13 +1256,18 @@ static int _fast_ping_get_addr_by_icmp(const char *ip_str, int port, struct addr
 		goto errout;
 	}

-	gai = _fast_ping_getaddr(ip_str, service, socktype, sockproto);
-	if (gai == NULL) {
-		goto errout;
+	if (out_gai != NULL) {
+		gai = _fast_ping_getaddr(ip_str, service, socktype, sockproto);
+		if (gai == NULL) {
+			goto errout;
+		}
+
+		*out_gai = gai;
 	}

-	*out_gai = gai;
-	*out_ping_type = ping_type;
+	if (out_ping_type != NULL) {
+		*out_ping_type = ping_type;
+	}

 	return 0;
 errout:
@@ -1150,6 +1401,8 @@ struct ping_host_struct *fast_ping_start(PING_TYPE type, const char *host, int c
 	FAST_PING_TYPE ping_type = FAST_PING_END;
 	unsigned int seed = 0;
 	int ret = 0;
+	struct fast_ping_fake_ip *fake = NULL;
+	int fake_time_fd = -1;

 	if (parse_ip(host, ip_str, &port) != 0) {
 		goto errout;
@@ -1194,6 +1447,19 @@ struct ping_host_struct *fast_ping_start(PING_TYPE type, const char *host, int c

 	tlog(TLOG_DEBUG, "ping %s, id = %d", host, ping_host->sid);

+	fake = _fast_ping_fake_find(ping_host->type, gai->ai_addr, gai->ai_addrlen);
+	if (fake) {
+		fake_time_fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK | TFD_CLOEXEC);
+		if (fake_time_fd < 0) {
+			tlog(TLOG_ERROR, "timerfd_create failed, %s", strerror(errno));
+			goto errout;
+		}
+		/* already take ownership by find. */
+		ping_host->fake = fake;
+		ping_host->fake_time_fd = fake_time_fd;
+		fake = NULL;
+	}
+
 	addrkey = _fast_ping_hash_key(ping_host->sid, &ping_host->addr);

 	_fast_ping_host_get(ping_host);
@@ -1229,6 +1495,14 @@ errout:
 		free(ping_host);
 	}

+	if (fake_time_fd > 0) {
+		close(fake_time_fd);
+	}
+
+	if (fake) {
+		_fast_ping_fake_put(fake);
+	}
+
 	return NULL;
 }

@@ -1365,6 +1639,33 @@ errout:
 	return NULL;
 }

+static int _fast_ping_process_fake(struct ping_host_struct *ping_host, struct timeval *now)
+{
+	struct timeval tvresult = *now;
+	struct timeval *tvsend = &ping_host->last;
+	uint64_t exp;
+	int ret;
+
+	ret = read(ping_host->fake_time_fd, &exp, sizeof(uint64_t));
+	if (ret < 0) {
+		return -1;
+	}
+
+	ping_host->ttl = ping_host->fake->ttl;
+	tv_sub(&tvresult, tvsend);
+	if (ping_host->ping_callback) {
+		_fast_ping_send_notify_event(ping_host, PING_RESULT_RESPONSE, ping_host->seq, ping_host->ttl, &tvresult);
+	}
+
+	ping_host->send = 0;
+
+	if (ping_host->count == 1) {
+		_fast_ping_host_remove(ping_host);
+	}
+
+	return 0;
+}
+
 static int _fast_ping_process_icmp(struct ping_host_struct *ping_host, struct timeval *now)
 {
 	int len = 0;
@@ -1592,6 +1893,11 @@ static int _fast_ping_process(struct ping_host_struct *ping_host, struct epoll_e
 {
 	int ret = -1;

+	if (ping_host->fake != NULL) {
+		ret = _fast_ping_process_fake(ping_host, now);
+		return ret;
+	}
+
 	switch (ping_host->type) {
 	case FAST_PING_ICMP6:
 	case FAST_PING_ICMP:
@@ -1635,6 +1941,18 @@ static void _fast_ping_remove_all(void)
 	}
 }

+static void _fast_ping_remove_all_fake_ip(void)
+{
+	struct fast_ping_fake_ip *fake = NULL;
+	struct hlist_node *tmp = NULL;
+	unsigned long i = 0;
+
+	hash_for_each_safe(ping.fake, i, tmp, fake, node)
+	{
+		_fast_ping_fake_put(fake);
+	}
+}
+
 static void _fast_ping_period_run(void)
 {
 	struct ping_host_struct *ping_host = NULL;
@@ -1890,6 +2208,7 @@ int fast_ping_init(void)
 	INIT_LIST_HEAD(&ping.notify_event_list);

 	hash_init(ping.addrmap);
+	hash_init(ping.fake);
 	ping.no_unprivileged_ping = !has_unprivileged_ping();
 	ping.ident = (getpid() & 0XFFFF);
 	atomic_set(&ping.run, 1);
@@ -1998,6 +2317,7 @@ void fast_ping_exit(void)

 	_fast_ping_close_fds();
 	_fast_ping_remove_all();
+	_fast_ping_remove_all_fake_ip();
 	_fast_ping_remove_all_notify_event();

 	pthread_cond_destroy(&ping.notify_cond);
--- a/src/fast_ping.h
+++ b/src/fast_ping.h
@@ -47,6 +47,10 @@ typedef void (*fast_ping_result)(struct ping_host_struct *ping_host, const char
 struct ping_host_struct *fast_ping_start(PING_TYPE type, const char *host, int count, int interval, int timeout,
 										 fast_ping_result ping_callback, void *userptr);

+int fast_ping_fake_ip_add(PING_TYPE type, const char *host, int ttl, float time);
+
+int fast_ping_fake_ip_remove(PING_TYPE type, const char *host);
+
 /* stop ping */
 int fast_ping_stop(struct ping_host_struct *ping_host);

--- a/src/smartdns.c
+++ b/src/smartdns.c
@@ -17,6 +17,7 @@
 */

 #define _GNU_SOURCE
+#include "smartdns.h"
 #include "art.h"
 #include "atomic.h"
 #include "dns_client.h"
@@ -304,8 +305,7 @@ static int _smartdns_add_servers(void)
 			}

 			if (_smartdns_prepare_server_flags(&flags, server) != 0) {
-				tlog(TLOG_ERROR, "prepare server flags failed, %s:%d", server->server,
-					 server->port);
+				tlog(TLOG_ERROR, "prepare server flags failed, %s:%d", server->server, server->port);
 				return -1;
 			}

@@ -647,16 +647,31 @@ static int _smartdns_init_pre(void)
 }

 #ifdef TEST
+
+static smartdns_post_func _smartdns_post = NULL;
+static void *_smartdns_post_arg = NULL;
+
+int smartdns_reg_post_func(smartdns_post_func func, void *arg)
+{
+	_smartdns_post = func;
+	_smartdns_post_arg = arg;
+	return 0;
+}
+
 #define smartdns_test_notify(retval) smartdns_test_notify_func(fd_notify, retval)
-static void smartdns_test_notify_func(int fd_notify, uint64_t retval) {
+static void smartdns_test_notify_func(int fd_notify, uint64_t retval)
+{
 	/* notify parent kickoff */
 	if (fd_notify > 0) {
 		write(fd_notify, &retval, sizeof(retval));
 	}
+
+	if (_smartdns_post != NULL) {
+		_smartdns_post(_smartdns_post_arg);
+	}
 }

-int smartdns_main(int argc, char *argv[], int fd_notify);
-int smartdns_main(int argc, char *argv[], int fd_notify) 
+int smartdns_main(int argc, char *argv[], int fd_notify)
 #else
 #define smartdns_test_notify(retval)
 int main(int argc, char *argv[])
--- a/src/smartdns.h
+++ b/src/smartdns.h
@@ -0,0 +1,39 @@
+/*************************************************************************
+ *
+ * Copyright (C) 2018-2023 Ruilin Peng (Nick) <pymumu@gmail.com>.
+ *
+ * smartdns 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.
+ *
+ * smartdns 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef SMART_DNS_H
+#define SMART_DNS_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif /*__cplusplus */
+
+#ifdef TEST
+
+typedef void (*smartdns_post_func)(void *arg);
+
+int smartdns_reg_post_func(smartdns_post_func func, void *arg);
+
+int smartdns_main(int argc, char *argv[], int fd_notify);
+
+#endif
+
+#ifdef __cplusplus
+}
+#endif /*__cplusplus */
+#endif
--- a/src/util.c
+++ b/src/util.c
@@ -310,7 +310,7 @@ int parse_ip(const char *value, char *ip, int *port)
 	return 0;
 }

-static int _check_is_ipv4(const char *ip)
+int check_is_ipv4(const char *ip)
 {
 	const char *ptr = ip;
 	char c = 0;
@@ -344,7 +344,8 @@ static int _check_is_ipv4(const char *ip)

 	return 0;
 }
-static int _check_is_ipv6(const char *ip)
+
+int check_is_ipv6(const char *ip)
 {
 	const char *ptr = ip;
 	char c = 0;
@@ -394,10 +395,10 @@ int check_is_ipaddr(const char *ip)
 {
 	if (strstr(ip, ".")) {
 		/* IPV4 */
-		return _check_is_ipv4(ip);
+		return check_is_ipv4(ip);
 	} else if (strstr(ip, ":")) {
 		/* IPV6 */
-		return _check_is_ipv6(ip);
+		return check_is_ipv6(ip);
 	}
 	return -1;
 }
--- a/src/util.h
+++ b/src/util.h
@@ -69,6 +69,10 @@ int parse_ip(const char *value, char *ip, int *port);

 int check_is_ipaddr(const char *ip);

+int check_is_ipv4(const char *ip);
+
+int check_is_ipv6(const char *ip);
+
 int parse_uri(const char *value, char *scheme, char *host, int *port, char *path);

 int parse_uri_ext(const char *value, char *scheme, char *user, char *password, char *host, int *port, char *path);
--- a/test/Makefile
+++ b/test/Makefile
@@ -20,6 +20,7 @@ CFLAGS += -DTEST
 CFLAGS += -g -Wall -Wstrict-prototypes -fno-omit-frame-pointer -Wstrict-aliasing -funwind-tables -Wmissing-prototypes -Wshadow -Wextra -Wno-unused-parameter -Wno-implicit-fallthrough

 CXXFLAGS += -g
+CXXFLAGS += -DTEST
 CXXFLAGS += -I./ -I../src -I../src/include

 SMARTDNS_OBJS = lib/rbtree.o lib/art.o lib/bitops.o lib/radix.o lib/conf.o lib/nftset.o
--- a/test/cases/test-address.cc
+++ b/test/cases/test-address.cc
@@ -61,7 +61,7 @@ cache-persist no)""");
 	smartdns::Client client;
 	ASSERT_TRUE(client.Query("a.com A", 60053));
 	std::cout << client.GetResult() << std::endl;
-	ASSERT_EQ(client.GetAnswerNum(), 0);
+	ASSERT_EQ(client.GetAuthorityNum(), 1);
 	EXPECT_EQ(client.GetStatus(), "NOERROR");
 	EXPECT_EQ(client.GetAuthority()[0].GetName(), "a.com");
 	EXPECT_EQ(client.GetAuthority()[0].GetTTL(), 30);
--- a/test/cases/test-bind.cc
+++ b/test/cases/test-bind.cc
@@ -160,4 +160,35 @@ cache-persist no)""");
 	EXPECT_EQ(client.GetAnswer()[0].GetName(), "a.com");
 	EXPECT_EQ(client.GetAnswer()[0].GetTTL(), 3);
 	EXPECT_EQ(client.GetAnswer()[0].GetData(), "1.2.3.4");
-}
+}
+
+TEST(Bind, device)
+{
+	smartdns::MockServer server_upstream;
+	smartdns::Server server;
+
+	server_upstream.Start("udp://0.0.0.0:62053", [](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype == DNS_T_A) {
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "1.2.3.4");
+			return smartdns::SERVER_REQUEST_OK;
+		}
+		return smartdns::SERVER_REQUEST_SOA;
+	});
+
+	server.Start(R"""(
+bind [::]:60053@lo
+server 127.0.0.1:62053
+log-num 0
+log-console yes
+log-level info
+cache-persist no)""");
+	smartdns::Client client;
+
+	ASSERT_TRUE(client.Query("a.com", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAnswerNum(), 1);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_LT(client.GetQueryTime(), 100);
+	EXPECT_EQ(client.GetAnswer()[0].GetTTL(), 3);
+	EXPECT_EQ(client.GetAnswer()[0].GetData(), "1.2.3.4");
+}
--- a/test/cases/test-bootstrap.cc
+++ b/test/cases/test-bootstrap.cc
@@ -0,0 +1,71 @@
+/*************************************************************************
+ *
+ * Copyright (C) 2018-2023 Ruilin Peng (Nick) <pymumu@gmail.com>.
+ *
+ * smartdns 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.
+ *
+ * smartdns 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "client.h"
+#include "dns.h"
+#include "include/utils.h"
+#include "server.h"
+#include "gtest/gtest.h"
+
+class BootStrap : public ::testing::Test
+{
+  protected:
+	virtual void SetUp() {}
+	virtual void TearDown() {}
+};
+
+TEST_F(BootStrap, bootstrap)
+{
+	smartdns::MockServer server_upstream;
+	smartdns::MockServer server_upstream2;
+	smartdns::Server server;
+
+	server_upstream.Start("udp://0.0.0.0:61053", [](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype != DNS_T_A) {
+			return smartdns::SERVER_REQUEST_SOA;
+		}
+
+		smartdns::MockServer::AddIP(request, request->domain.c_str(), "1.2.3.4", 611);
+		return smartdns::SERVER_REQUEST_OK;
+	});
+
+	server_upstream2.Start("udp://0.0.0.0:62053", [](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype != DNS_T_A) {
+			return smartdns::SERVER_REQUEST_SOA;
+		}
+
+		smartdns::MockServer::AddIP(request, request->domain.c_str(), "127.0.0.1", 611);
+		return smartdns::SERVER_REQUEST_OK;
+	});
+
+	server.Start(R"""(bind [::]:60053
+server udp://127.0.0.1:62053 -bootstrap-dns
+server udp://example.com:61053
+log-num 0
+log-console yes
+log-level debug
+cache-persist no)""");
+	smartdns::Client client;
+	usleep(2500000);
+	ASSERT_TRUE(client.Query("a.com", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAnswerNum(), 1);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_EQ(client.GetAnswer()[0].GetName(), "a.com");
+	EXPECT_EQ(client.GetAnswer()[0].GetData(), "1.2.3.4");
+}
--- a/test/cases/test-cache.cc
+++ b/test/cases/test-cache.cc
@@ -21,6 +21,11 @@
 #include "include/utils.h"
 #include "server.h"
 #include "gtest/gtest.h"
+#include <fstream>
+
+/* clang-format off */
+#include "dns_cache.h"
+/* clang-format on */

 class Cache : public ::testing::Test
 {
@@ -228,3 +233,56 @@ cache-persist no)""");
 	EXPECT_EQ(client.GetAnswer()[0].GetTTL(), 3);
 	EXPECT_EQ(client.GetAnswer()[0].GetData(), "1.2.3.4");
 }
+
+TEST_F(Cache, save_file)
+{
+	smartdns::MockServer server_upstream;
+	auto cache_file = "/tmp/smartdns_cache." + smartdns::GenerateRandomString(10);
+	std::string conf = R"""(
+bind [::]:60053@lo
+server 127.0.0.1:62053
+log-num 0
+log-console yes
+log-level debug
+cache-persist yes
+dualstack-ip-selection no
+)""";
+
+	conf += "cache-file " + cache_file;
+	Defer
+	{
+		unlink(cache_file.c_str());
+	};
+
+	server_upstream.Start("udp://0.0.0.0:62053", [](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype == DNS_T_A) {
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "1.2.3.4");
+			return smartdns::SERVER_REQUEST_OK;
+		}
+		return smartdns::SERVER_REQUEST_SOA;
+	});
+	{
+		smartdns::Server server;
+		server.Start(conf);
+		smartdns::Client client;
+
+		ASSERT_TRUE(client.Query("a.com", 60053));
+		std::cout << client.GetResult() << std::endl;
+		ASSERT_EQ(client.GetAnswerNum(), 1);
+		EXPECT_EQ(client.GetStatus(), "NOERROR");
+		EXPECT_LT(client.GetQueryTime(), 100);
+		EXPECT_EQ(client.GetAnswer()[0].GetTTL(), 3);
+		EXPECT_EQ(client.GetAnswer()[0].GetData(), "1.2.3.4");
+		server.Stop();
+		usleep(200 * 1000);
+	}
+
+	ASSERT_EQ(access(cache_file.c_str(), F_OK), 0);
+
+	std::fstream fs(cache_file, std::ios::in);
+	struct dns_cache_file head;
+	memset(&head, 0, sizeof(head));
+	fs.read((char *)&head, sizeof(head));
+	EXPECT_EQ(head.magic, MAGIC_NUMBER);
+	EXPECT_EQ(head.cache_number, 1);
+}
--- a/test/cases/test-cname.cc
+++ b/test/cases/test-cname.cc
@@ -22,7 +22,14 @@
 #include "server.h"
 #include "gtest/gtest.h"

-TEST(server, cname)
+class Cname : public ::testing::Test
+{
+  protected:
+	virtual void SetUp() {}
+	virtual void TearDown() {}
+};
+
+TEST_F(Cname, cname)
 {
 	smartdns::MockServer server_upstream;
 	smartdns::Server server;
@@ -32,11 +39,8 @@ TEST(server, cname)
 			return smartdns::SERVER_REQUEST_SOA;
 		}

-		unsigned char addr[4] = {1, 2, 3, 4};
-		dns_add_A(request->response_packet, DNS_RRS_AN, request->domain.c_str(), 611, addr);
+		smartdns::MockServer::AddIP(request, request->domain.c_str(), "1.2.3.4", 611);
 		EXPECT_EQ(request->domain, "e.com");
-
-		request->response_packet->head.rcode = DNS_RC_NOERROR;
 		return smartdns::SERVER_REQUEST_OK;
 	});

--- a/test/cases/test-dualstack.cc
+++ b/test/cases/test-dualstack.cc
@@ -0,0 +1,187 @@
+/*************************************************************************
+ *
+ * Copyright (C) 2018-2023 Ruilin Peng (Nick) <pymumu@gmail.com>.
+ *
+ * smartdns 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.
+ *
+ * smartdns 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "client.h"
+#include "dns.h"
+#include "include/utils.h"
+#include "server.h"
+#include "util.h"
+#include "gtest/gtest.h"
+#include <fstream>
+
+class DualStack : public ::testing::Test
+{
+  protected:
+	virtual void SetUp() {}
+	virtual void TearDown() {}
+};
+
+TEST_F(DualStack, ipv4_prefer)
+{
+	smartdns::MockServer server_upstream;
+	smartdns::Server server;
+	std::map<int, int> qid_map;
+
+	server_upstream.Start("udp://0.0.0.0:61053", [&](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype == DNS_T_A) {
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "1.2.3.4");
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "5.6.7.8");
+			return smartdns::SERVER_REQUEST_OK;
+		} else if (request->qtype == DNS_T_AAAA) {
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "2001:db8::1");
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "2001:db8::2");
+			return smartdns::SERVER_REQUEST_OK;
+		}
+		return smartdns::SERVER_REQUEST_SOA;
+	});
+
+	server.MockPing(PING_TYPE_ICMP, "1.2.3.4", 60, 100);
+	server.MockPing(PING_TYPE_ICMP, "5.6.7.8", 60, 110);
+	server.MockPing(PING_TYPE_ICMP, "2001:db8::1", 60, 150);
+	server.MockPing(PING_TYPE_ICMP, "2001:db8::2", 60, 150);
+
+	server.Start(R"""(bind [::]:60053
+server 127.0.0.1:61053
+log-num 0
+log-console yes
+speed-check-mode ping
+log-level debug
+cache-persist no)""");
+	smartdns::Client client;
+	ASSERT_TRUE(client.Query("a.com AAAA", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAuthorityNum(), 1);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_EQ(client.GetAuthority()[0].GetName(), "a.com");
+	EXPECT_EQ(client.GetAuthority()[0].GetTTL(), 3);
+	EXPECT_EQ(client.GetAuthority()[0].GetType(), "SOA");
+
+	usleep(220 * 1000);
+	ASSERT_TRUE(client.Query("a.com", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAnswerNum(), 2);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_LT(client.GetQueryTime(), 20);
+	EXPECT_EQ(client.GetAnswer()[0].GetName(), "a.com");
+	EXPECT_GT(client.GetAnswer()[0].GetTTL(), 597);
+	EXPECT_EQ(client.GetAnswer()[0].GetData(), "1.2.3.4");
+	EXPECT_EQ(client.GetAnswer()[1].GetData(), "5.6.7.8");
+}
+
+TEST_F(DualStack, ipv6_prefer_allow_force_AAAA)
+{
+	smartdns::MockServer server_upstream;
+	smartdns::Server server;
+
+	server_upstream.Start("udp://0.0.0.0:61053", [&](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype == DNS_T_A) {
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "1.2.3.4");
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "5.6.7.8");
+			return smartdns::SERVER_REQUEST_OK;
+		} else if (request->qtype == DNS_T_AAAA) {
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "2001:db8::1");
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "2001:db8::2");
+			return smartdns::SERVER_REQUEST_OK;
+		}
+		return smartdns::SERVER_REQUEST_SOA;
+	});
+
+	server.MockPing(PING_TYPE_ICMP, "1.2.3.4", 60, 100);
+	server.MockPing(PING_TYPE_ICMP, "5.6.7.8", 60, 110);
+	server.MockPing(PING_TYPE_ICMP, "2001:db8::1", 60, 70);
+	server.MockPing(PING_TYPE_ICMP, "2001:db8::2", 60, 75);
+
+	server.Start(R"""(bind [::]:60053
+server 127.0.0.1:61053
+log-num 0
+log-console yes
+speed-check-mode ping
+dualstack-ip-allow-force-AAAA yes
+log-level debug
+cache-persist no)""");
+	smartdns::Client client;
+	ASSERT_TRUE(client.Query("a.com A", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAuthorityNum(), 1);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_EQ(client.GetAuthority()[0].GetName(), "a.com");
+	EXPECT_EQ(client.GetAuthority()[0].GetTTL(), 3);
+	EXPECT_EQ(client.GetAuthority()[0].GetType(), "SOA");
+
+	usleep(220 * 1000);
+	ASSERT_TRUE(client.Query("a.com AAAA", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAnswerNum(), 2);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_LT(client.GetQueryTime(), 20);
+	EXPECT_EQ(client.GetAnswer()[0].GetName(), "a.com");
+	EXPECT_GT(client.GetAnswer()[0].GetTTL(), 597);
+	EXPECT_EQ(client.GetAnswer()[0].GetData(), "2001:db8::1");
+	EXPECT_EQ(client.GetAnswer()[1].GetData(), "2001:db8::2");
+}
+
+TEST_F(DualStack, ipv6_prefer_must_exist_ipv4)
+{
+	smartdns::MockServer server_upstream;
+	smartdns::Server server;
+
+	server_upstream.Start("udp://0.0.0.0:61053", [&](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype == DNS_T_A) {
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "1.2.3.4");
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "5.6.7.8");
+			return smartdns::SERVER_REQUEST_OK;
+		} else if (request->qtype == DNS_T_AAAA) {
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "2001:db8::1");
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "2001:db8::2");
+			return smartdns::SERVER_REQUEST_OK;
+		}
+		return smartdns::SERVER_REQUEST_SOA;
+	});
+
+	server.MockPing(PING_TYPE_ICMP, "1.2.3.4", 60, 100);
+	server.MockPing(PING_TYPE_ICMP, "5.6.7.8", 60, 110);
+	server.MockPing(PING_TYPE_ICMP, "2001:db8::1", 60, 70);
+	server.MockPing(PING_TYPE_ICMP, "2001:db8::2", 60, 100);
+
+	server.Start(R"""(bind [::]:60053
+server 127.0.0.1:61053
+log-num 0
+log-console yes
+speed-check-mode ping
+dualstack-ip-allow-force-AAAA yes
+log-level debug
+cache-persist no)""");
+	smartdns::Client client;
+	ASSERT_TRUE(client.Query("a.com A", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAuthorityNum(), 1);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_EQ(client.GetAuthority()[0].GetName(), "a.com");
+	EXPECT_EQ(client.GetAuthority()[0].GetTTL(), 3);
+	EXPECT_EQ(client.GetAuthority()[0].GetType(), "SOA");
+
+	usleep(220 * 1000);
+	ASSERT_TRUE(client.Query("a.com AAAA", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAnswerNum(), 1);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_LT(client.GetQueryTime(), 20);
+	EXPECT_EQ(client.GetAnswer()[0].GetName(), "a.com");
+	EXPECT_GT(client.GetAnswer()[0].GetTTL(), 597);
+	EXPECT_EQ(client.GetAnswer()[0].GetData(), "2001:db8::1");
+}
--- a/test/cases/test-nameserver.cc
+++ b/test/cases/test-nameserver.cc
@@ -0,0 +1,97 @@
+/*************************************************************************
+ *
+ * Copyright (C) 2018-2023 Ruilin Peng (Nick) <pymumu@gmail.com>.
+ *
+ * smartdns 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.
+ *
+ * smartdns 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "client.h"
+#include "dns.h"
+#include "include/utils.h"
+#include "server.h"
+#include "gtest/gtest.h"
+
+class NameServer : public ::testing::Test
+{
+  protected:
+	virtual void SetUp() {}
+	virtual void TearDown() {}
+};
+
+TEST_F(NameServer, cname)
+{
+	smartdns::MockServer server_upstream;
+	smartdns::MockServer server_upstream1;
+	smartdns::MockServer server_upstream2;
+	smartdns::Server server;
+
+	server_upstream.Start("udp://0.0.0.0:61053", [](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype != DNS_T_A) {
+			return smartdns::SERVER_REQUEST_SOA;
+		}
+
+		smartdns::MockServer::AddIP(request, request->domain.c_str(), "9.10.11.12", 611);
+		return smartdns::SERVER_REQUEST_OK;
+	});
+
+	server_upstream1.Start("udp://0.0.0.0:62053", [](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype != DNS_T_A) {
+			return smartdns::SERVER_REQUEST_SOA;
+		}
+
+		smartdns::MockServer::AddIP(request, request->domain.c_str(), "1.2.3.4", 611);
+		return smartdns::SERVER_REQUEST_OK;
+	});
+
+	server_upstream2.Start("udp://0.0.0.0:63053", [](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype != DNS_T_A) {
+			return smartdns::SERVER_REQUEST_SOA;
+		}
+
+		smartdns::MockServer::AddIP(request, request->domain.c_str(), "5.6.7.8", 611);
+		return smartdns::SERVER_REQUEST_OK;
+	});
+
+	server.Start(R"""(bind [::]:60053
+server 127.0.0.1:61053
+server 127.0.0.1:62053 -group g1 -exclude-default-group
+server 127.0.0.1:63053 -group g2 -exclude-default-group
+nameserver /a.com/g1
+nameserver /b.com/g2
+log-num 0
+log-console yes
+log-level debug
+cache-persist no)""");
+	smartdns::Client client;
+	ASSERT_TRUE(client.Query("a.com", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAnswerNum(), 1);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_EQ(client.GetAnswer()[0].GetName(), "a.com");
+	EXPECT_EQ(client.GetAnswer()[0].GetData(), "1.2.3.4");
+
+	ASSERT_TRUE(client.Query("b.com", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAnswerNum(), 1);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_EQ(client.GetAnswer()[0].GetName(), "b.com");
+	EXPECT_EQ(client.GetAnswer()[0].GetData(), "5.6.7.8");
+
+	ASSERT_TRUE(client.Query("c.com", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAnswerNum(), 1);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_EQ(client.GetAnswer()[0].GetName(), "c.com");
+	EXPECT_EQ(client.GetAnswer()[0].GetData(), "9.10.11.12");
+}
--- a/test/cases/test-ping.cc
+++ b/test/cases/test-ping.cc
@@ -71,3 +71,27 @@ TEST_F(Ping, tcp)
 	fast_ping_stop(ping_host);
 	EXPECT_EQ(count, 1);
 }
+
+void fake_ping_result_callback(struct ping_host_struct *ping_host, const char *host, FAST_PING_RESULT result,
+							   struct sockaddr *addr, socklen_t addr_len, int seqno, int ttl, struct timeval *tv,
+							   int error, void *userptr)
+{
+	if (result == PING_RESULT_RESPONSE) {
+		int *count = (int *)userptr;
+		double rtt = tv->tv_sec * 1000.0 + tv->tv_usec / 1000.0;
+		tlog(TLOG_INFO, "from %15s: seq=%d ttl=%d time=%.3f\n", host, seqno, ttl, rtt);
+		*count = (int)rtt;
+	}
+}
+
+TEST_F(Ping, fake_icmp)
+{
+	struct ping_host_struct *ping_host;
+	int count = 0;
+	fast_ping_fake_ip_add(PING_TYPE_ICMP, "1.2.3.4", 60, 5);
+	ping_host = fast_ping_start(PING_TYPE_ICMP, "1.2.3.4", 1, 1000, 200, fake_ping_result_callback, &count);
+	ASSERT_NE(ping_host, nullptr);
+	usleep(100000);
+	fast_ping_stop(ping_host);
+	EXPECT_GE(count, 5);
+}
--- a/test/cases/test-qtype-soa.cc
+++ b/test/cases/test-qtype-soa.cc
@@ -0,0 +1,78 @@
+/*************************************************************************
+ *
+ * Copyright (C) 2018-2023 Ruilin Peng (Nick) <pymumu@gmail.com>.
+ *
+ * smartdns 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.
+ *
+ * smartdns 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "client.h"
+#include "dns.h"
+#include "include/utils.h"
+#include "server.h"
+#include "gtest/gtest.h"
+
+class QtypeSOA : public ::testing::Test
+{
+  protected:
+	virtual void SetUp() {}
+	virtual void TearDown() {}
+};
+
+TEST_F(QtypeSOA, AAAA_HTTPS)
+{
+	smartdns::MockServer server_upstream;
+	smartdns::Server server;
+
+	server_upstream.Start("udp://0.0.0.0:61053", [](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype == DNS_T_A) {
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "1.2.3.4");
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "5.6.7.8");
+			return smartdns::SERVER_REQUEST_OK;
+		} else if (request->qtype == DNS_T_AAAA) {
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "2001:db8::1");
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "2001:db8::2");
+			return smartdns::SERVER_REQUEST_OK;
+		}
+		return smartdns::SERVER_REQUEST_SOA;
+	});
+
+	server.Start(R"""(bind [::]:60053
+server 127.0.0.1:61053
+log-num 0
+log-console yes
+log-level debug
+force-qtype-SOA 28 65
+cache-persist no)""");
+	smartdns::Client client;
+	ASSERT_TRUE(client.Query("a.com AAAA", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAuthorityNum(), 1);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_EQ(client.GetAuthority()[0].GetName(), "a.com");
+	EXPECT_EQ(client.GetAuthority()[0].GetTTL(), 30);
+	EXPECT_EQ(client.GetAuthority()[0].GetType(), "SOA");
+
+	ASSERT_TRUE(client.Query("a.com -t HTTPS", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAuthorityNum(), 1);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_EQ(client.GetAuthority()[0].GetName(), "a.com");
+	EXPECT_EQ(client.GetAuthority()[0].GetTTL(), 30);
+	EXPECT_EQ(client.GetAuthority()[0].GetType(), "SOA");
+
+	ASSERT_TRUE(client.Query("a.com A", 60053));
+	ASSERT_EQ(client.GetAnswerNum(), 1);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_EQ(client.GetAnswer()[0].GetName(), "a.com");
+}
--- a/test/cases/test-speed-check.cc
+++ b/test/cases/test-speed-check.cc
@@ -189,3 +189,146 @@ cache-persist no)""");
 	EXPECT_EQ(client.GetAnswer()[0].GetName(), "b.com");
 	EXPECT_EQ(client.GetAnswer()[0].GetTTL(), 600);
 }
+
+TEST_F(SpeedCheck, fastest_ip)
+{
+	smartdns::MockServer server_upstream;
+	smartdns::Server server;
+
+	server_upstream.Start("udp://0.0.0.0:61053", [&](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype == DNS_T_A) {
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "1.2.3.4");
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "5.6.7.8");
+			return smartdns::SERVER_REQUEST_OK;
+		}
+		return smartdns::SERVER_REQUEST_SOA;
+	});
+
+	server.MockPing(PING_TYPE_ICMP, "1.2.3.4", 60, 100);
+	server.MockPing(PING_TYPE_ICMP, "5.6.7.8", 60, 110);
+
+	server.Start(R"""(bind [::]:60053
+server 127.0.0.1:61053
+log-num 0
+log-console yes
+speed-check-mode ping
+dualstack-ip-selection no
+log-level debug
+cache-persist no)""");
+	smartdns::Client client;
+	ASSERT_TRUE(client.Query("b.com", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAnswerNum(), 1);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_LT(client.GetQueryTime(), 200);
+	EXPECT_EQ(client.GetAnswer()[0].GetName(), "b.com");
+	EXPECT_EQ(client.GetAnswer()[0].GetTTL(), 3);
+	EXPECT_EQ(client.GetAnswer()[0].GetData(), "1.2.3.4");
+
+	usleep(220 * 1000);
+	ASSERT_TRUE(client.Query("b.com", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAnswerNum(), 2);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_LT(client.GetQueryTime(), 20);
+	EXPECT_EQ(client.GetAnswer()[0].GetName(), "b.com");
+	EXPECT_GT(client.GetAnswer()[0].GetTTL(), 597);
+	EXPECT_EQ(client.GetAnswer()[0].GetData(), "1.2.3.4");
+	EXPECT_EQ(client.GetAnswer()[1].GetData(), "5.6.7.8");
+}
+
+TEST_F(SpeedCheck, unreach_best_ipv4)
+{
+	smartdns::MockServer server_upstream;
+	smartdns::MockServer server_upstream2;
+	smartdns::Server server;
+
+	server_upstream.Start("udp://0.0.0.0:61053", [&](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype == DNS_T_A) {
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "1.2.3.4");
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "5.6.7.8");
+			return smartdns::SERVER_REQUEST_OK;
+		}
+		return smartdns::SERVER_REQUEST_SOA;
+	});
+
+	server_upstream2.Start("udp://0.0.0.0:62053", [&](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype == DNS_T_A) {
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "1.2.3.4");
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "9.10.11.12");
+			return smartdns::SERVER_REQUEST_OK;
+		}
+		return smartdns::SERVER_REQUEST_SOA;
+	});
+
+	server.MockPing(PING_TYPE_ICMP, "1.2.3.4", 60, 10000);
+	server.MockPing(PING_TYPE_ICMP, "5.6.7.8", 60, 10000);
+	server.MockPing(PING_TYPE_ICMP, "9.10.11.12", 60, 10000);
+
+	server.Start(R"""(bind [::]:60053
+server 127.0.0.1:61053
+server 127.0.0.1:62053
+log-num 0
+log-console yes
+speed-check-mode ping
+dualstack-ip-selection no
+log-level debug
+cache-persist no)""");
+	smartdns::Client client;
+	ASSERT_TRUE(client.Query("a.com", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAnswerNum(), 1);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_LT(client.GetQueryTime(), 1200);
+	EXPECT_EQ(client.GetAnswer()[0].GetName(), "a.com");
+	EXPECT_GT(client.GetAnswer()[0].GetTTL(), 597);
+	EXPECT_EQ(client.GetAnswer()[0].GetData(), "1.2.3.4");
+}
+
+TEST_F(SpeedCheck, unreach_best_ipv6)
+{
+	smartdns::MockServer server_upstream;
+	smartdns::MockServer server_upstream2;
+	smartdns::Server server;
+
+	server_upstream.Start("udp://0.0.0.0:61053", [&](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype == DNS_T_AAAA) {
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "2001:db8::1");
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "2001:db8::2");
+			return smartdns::SERVER_REQUEST_OK;
+		}
+		return smartdns::SERVER_REQUEST_SOA;
+	});
+
+	server_upstream2.Start("udp://0.0.0.0:62053", [&](struct smartdns::ServerRequestContext *request) {
+		if (request->qtype == DNS_T_AAAA) {
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "2001:db8::2");
+			smartdns::MockServer::AddIP(request, request->domain.c_str(), "2001:db8::3");
+			return smartdns::SERVER_REQUEST_OK;
+		}
+		return smartdns::SERVER_REQUEST_SOA;
+	});
+
+	server.MockPing(PING_TYPE_ICMP, "2001:db8::1", 60, 10000);
+	server.MockPing(PING_TYPE_ICMP, "2001:db8::2", 60, 10000);
+	server.MockPing(PING_TYPE_ICMP, "2001:db8::3", 60, 10000);
+
+	server.Start(R"""(bind [::]:60053
+server 127.0.0.1:61053
+server 127.0.0.1:62053
+log-num 0
+log-console yes
+speed-check-mode ping
+dualstack-ip-selection no
+log-level debug
+cache-persist no)""");
+	smartdns::Client client;
+	ASSERT_TRUE(client.Query("a.com AAAA", 60053));
+	std::cout << client.GetResult() << std::endl;
+	ASSERT_EQ(client.GetAnswerNum(), 1);
+	EXPECT_EQ(client.GetStatus(), "NOERROR");
+	EXPECT_LT(client.GetQueryTime(), 1200);
+	EXPECT_EQ(client.GetAnswer()[0].GetName(), "a.com");
+	EXPECT_GT(client.GetAnswer()[0].GetTTL(), 597);
+	EXPECT_EQ(client.GetAnswer()[0].GetData(), "2001:db8::2");
+}
--- a/test/client.cc
+++ b/test/client.cc
@@ -173,6 +173,11 @@ int Client::GetAnswerNum()
 	return answer_num_;
 }

+int Client::GetAuthorityNum()
+{
+	return authority_num_;
+}
+
 std::string Client::GetStatus()
 {
 	return status_;
@@ -257,7 +262,7 @@ bool Client::ParserResult()

 	std::regex reg_authority_num(", AUTHORITY: ([0-9]+),");
 	if (std::regex_search(result_, match, reg_authority_num)) {
-		records_authority_num_ = std::stoi(match[1]);
+		authority_num_ = std::stoi(match[1]);
 	}

 	std::regex reg_status(", status: ([A-Z]+),");
@@ -313,7 +318,7 @@ bool Client::ParserResult()
 			return false;
 		}

-		if (records_authority_num_ != records_authority_.size()) {
+		if (authority_num_ != records_authority_.size()) {
 			std::cout << "DIG FAILED: Num Not Match\n" << result_ << std::endl;
 			return false;
 		}
--- a/test/client.h
+++ b/test/client.h
@@ -71,6 +71,8 @@ class Client

 	int GetAnswerNum();

+	int GetAuthorityNum();
+
 	std::string GetStatus();

 	std::string GetServer();
@@ -90,7 +92,7 @@ class Client
 	bool ParserRecord(const std::string &record_str, std::vector<DNSRecord> &record);
 	std::string result_;
 	int answer_num_{0};
-	int records_authority_num_{0};
+	int authority_num_{0};
 	std::string status_;
 	std::string server_;
 	int query_time_{0};
--- a/test/server.cc
+++ b/test/server.cc
@@ -18,7 +18,9 @@

 #include "server.h"
 #include "dns_server.h"
+#include "fast_ping.h"
 #include "include/utils.h"
+#include "smartdns.h"
 #include "util.h"
 #include <arpa/inet.h>
 #include <fcntl.h>
@@ -36,8 +38,6 @@
 namespace smartdns
 {

-extern "C" int smartdns_main(int argc, char *argv[], int fd_notify);
-
 MockServer::MockServer() {}

 MockServer::~MockServer()
@@ -293,6 +293,34 @@ Server::Server(enum Server::CREATE_MODE mode)
 	mode_ = mode;
 }

+void Server::MockPing(PING_TYPE type, const std::string &host, int ttl, float time)
+{
+	struct MockPingIP ping_ip;
+	ping_ip.type = type;
+	ping_ip.host = host;
+	ping_ip.ttl = ttl;
+	ping_ip.time = time;
+	mock_ping_ips_.push_back(ping_ip);
+}
+
+void Server::StartPost(void *arg)
+{
+	Server *server = (Server *)arg;
+	bool has_ipv6 = false;
+	for (auto &it : server->mock_ping_ips_) {
+		if (has_ipv6 == false && check_is_ipv6(it.host.c_str()) == 0) {
+			has_ipv6 = true;
+		}
+
+		fast_ping_fake_ip_add(it.type, it.host.c_str(), it.ttl, it.time);
+	}
+
+	if (has_ipv6 == true) {
+		fast_ping_fake_ip_add(PING_TYPE_ICMP, "2001::", 64, 10);
+		dns_server_check_ipv6_ready();
+	}
+}
+
 bool Server::Start(const std::string &conf, enum CONF_TYPE type)
 {
 	pid_t pid = 0;
@@ -343,6 +371,7 @@ bool Server::Start(const std::string &conf, enum CONF_TYPE type)
 				argv[i] = (char *)args[i].c_str();
 			}

+			smartdns_reg_post_func(Server::StartPost, this);
 			smartdns_main(args.size(), argv, fds[1]);
 			_exit(1);
 		} else if (pid < 0) {
@@ -358,7 +387,9 @@ bool Server::Start(const std::string &conf, enum CONF_TYPE type)
 				argv[i] = (char *)args[i].c_str();
 			}

+			smartdns_reg_post_func(Server::StartPost, this);
 			smartdns_main(args.size(), argv, fds[1]);
+			smartdns_reg_post_func(nullptr, nullptr);
 		});
 	} else {
 		return false;
--- a/test/server.h
+++ b/test/server.h
@@ -20,12 +20,14 @@
 #define _SMARTDNS_SERVER_

 #include "dns.h"
+#include "fast_ping.h"
 #include "include/utils.h"
 #include <functional>
 #include <string>
 #include <sys/socket.h>
 #include <thread>
 #include <unistd.h>
+#include <vector>

 namespace smartdns
 {
@@ -33,6 +35,12 @@ namespace smartdns
 class Server
 {
  public:
+	struct MockPingIP {
+		PING_TYPE type;
+		std::string host;
+		int ttl;
+		float time;
+	};
 	enum CONF_TYPE {
 		CONF_TYPE_STRING,
 		CONF_TYPE_FILE,
@@ -45,17 +53,19 @@ class Server
 	Server(enum CREATE_MODE mode);
 	virtual ~Server();

+	void MockPing(PING_TYPE type, const std::string &host, int ttl, float time);
 	bool Start(const std::string &conf, enum CONF_TYPE type = CONF_TYPE_STRING);
 	void Stop(bool graceful = true);
 	bool IsRunning();

  private:
+	static void StartPost(void *arg);
 	pid_t pid_;
 	std::thread thread_;
 	int fd_;
 	std::string conf_file_;
 	TempFile conf_temp_file_;
-
+	std::vector<MockPingIP> mock_ping_ips_;
 	enum CREATE_MODE mode_;
 };

@@ -100,10 +110,10 @@ class MockServer

 	static bool GetAddr(const std::string &host, const std::string port, int type, int protocol,
 						struct sockaddr_storage *addr, socklen_t *addrlen);
-	int fd_;
+	int fd_{0};
 	std::thread thread_;
-	bool run_;
-	ServerRequest callback_;
+	bool run_{false};
+	ServerRequest callback_{nullptr};
 };

 } // namespace smartdns