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Fix tcp connection timeout issue

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This commit is contained in:
Nick Peng
2019-02-10 23:29:34 +08:00
parent 46d3acdb8f
commit 0085abdfdd
2 changed files with 95 additions and 32 deletions
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120
src/dns_client.c
View File

@@ -50,6 +50,8 @@
#define DNS_MAX_EVENTS 64
#define DNS_HOSTNAME_LEN 128
#define DNS_TCP_BUFFER (32 * 1024)
#define DNS_TCP_IDLE_TIMEOUT (60 * 10)
#define DNS_TCP_CONNECT_TIMEOUT (5)
#ifndef TCP_FASTOPEN_CONNECT
#define TCP_FASTOPEN_CONNECT 30
@@ -109,6 +111,7 @@ struct dns_server_info {
/* server ping handle */
struct ping_host_struct *ping_host;
char ip[DNS_HOSTNAME_LEN];
/* server type */
dns_server_type_t type;
@@ -242,7 +245,7 @@ void _dns_client_server_update_ttl(struct ping_host_struct *ping_host, const cha
}
double rtt = tv->tv_sec * 1000.0 + tv->tv_usec / 1000.0;
tlog(TLOG_DEBUG, "from %15s: seq=%d ttl=%d time=%.3f\n", host, seqno, ttl, rtt);
tlog(TLOG_DEBUG, "from %s: seq=%d ttl=%d time=%.3f\n", host, seqno, ttl, rtt);
server_info->ttl = ttl;
}
@@ -265,6 +268,7 @@ int _dns_client_server_add(char *server_ip, struct addrinfo *gai, dns_server_typ
}
memset(server_info, 0, sizeof(*server_info));
strncpy(server_info->ip, server_ip, sizeof(server_info->ip));
server_info->ai_family = gai->ai_family;
server_info->ai_addrlen = gai->ai_addrlen;
server_info->type = server_type;
@@ -341,6 +345,9 @@ static void _dns_client_close_socket(struct dns_server_info *server_info)
server_info->fd = -1;
server_info->status = DNS_SERVER_STATUS_DISCONNECTED;
time(&server_info->last_send);
time(&server_info->last_recv);
tlog(TLOG_DEBUG, "server %s closed.", server_info->ip);
}
static void _dns_client_server_close(struct dns_server_info *server_info)
@@ -553,10 +560,72 @@ void _dns_client_query_remove_all(void)
return;
}
void _dns_client_check_udp_nat(void)
{
struct dns_server_info *server_info;
/* For udp nat case.
* when router reconnect to internet, udp port may always marked as UNREPLIED.
* dns query will timeout, and cannot reconnect again,
* create a new socket to communicate.
*/
pthread_mutex_lock(&client.server_list_lock);
list_for_each_entry(server_info, &client.dns_server_list, list)
{
if (server_info->type != DNS_SERVER_UDP) {
continue;
}
if (server_info->last_send - 5 > server_info->last_recv) {
server_info->recv_buff.len = 0;
server_info->send_buff.len = 0;
tlog(TLOG_DEBUG, "query server %s timeout.", server_info->ip);
_dns_client_close_socket(server_info);
}
}
pthread_mutex_unlock(&client.server_list_lock);
}
void _dns_client_check_tcp(void)
{
struct dns_server_info *server_info;
time_t now;
time(&now);
pthread_mutex_lock(&client.server_list_lock);
list_for_each_entry(server_info, &client.dns_server_list, list)
{
if (server_info->type == DNS_SERVER_UDP) {
continue;
}
if (server_info->status == DNS_SERVER_STATUS_CONNECTING) {
if (server_info->last_send + DNS_TCP_CONNECT_TIMEOUT < now) {
tlog(TLOG_DEBUG, "server %s connect timeout.", server_info->ip);
_dns_client_close_socket(server_info);
}
} else if (server_info->status == DNS_SERVER_STATUS_CONNECTED) {
if (server_info->last_recv + DNS_TCP_IDLE_TIMEOUT < now) {
server_info->recv_buff.len = 0;
server_info->send_buff.len = 0;
_dns_client_close_socket(server_info);
}
}
}
pthread_mutex_unlock(&client.server_list_lock);
}
void _dns_client_period_run_second(void)
{
_dns_client_check_tcp();
}
void _dns_client_period_run(void)
{
struct dns_query_struct *query, *tmp;
struct dns_server_info *server_info;
static unsigned int msec = 0;
msec++;
LIST_HEAD(check_list);
unsigned long now = get_tick_count();
@@ -579,21 +648,12 @@ void _dns_client_period_run(void)
_dns_client_query_remove(query);
_dns_client_query_release(query);
/* For udp nat case.
* when router reconnect to internet, udp port may always marked as UNREPLIED.
* dns query will timeout, and cannot reconnect again,
* create a new socket to communicate.
*/
pthread_mutex_lock(&client.server_list_lock);
list_for_each_entry(server_info, &client.dns_server_list, list)
{
if (server_info->last_send - 5 > server_info->last_recv) {
server_info->recv_buff.len = 0;
server_info->send_buff.len = 0;
_dns_client_close_socket(server_info);
}
}
pthread_mutex_unlock(&client.server_list_lock);
_dns_client_check_udp_nat();
}
if (msec % 10 == 0) {
_dns_client_period_run_second();
}
return;
@@ -825,6 +885,8 @@ static int _DNS_client_create_socket_tcp(struct dns_server_info *server_info)
server_info->fd = fd;
server_info->status = DNS_SERVER_STATUS_CONNECTING;
tlog(TLOG_DEBUG, "tcp server %s connecting.\n", server_info->ip);
return 0;
errout:
if (fd > 0) {
@@ -898,7 +960,7 @@ static int _DNS_client_create_socket_tls(struct dns_server_info *server_info)
server_info->ssl = ssl;
server_info->status = DNS_SERVER_STATUS_CONNECTING;
tlog(TLOG_DEBUG, "TLS server connecting.\n");
tlog(TLOG_DEBUG, "tls server %s connecting.\n", server_info->ip);
return 0;
errout:
@@ -979,7 +1041,7 @@ static int _dns_client_process_udp(struct dns_server_info *server_info, struct e
}
}
tlog(TLOG_DEBUG, "recv udp, from %s, len: %d, ttl: %d", gethost_by_addr(from_host, (struct sockaddr *)&from, from_len), len, ttl);
tlog(TLOG_DEBUG, "recv udp packet from %s, len: %d, ttl: %d", gethost_by_addr(from_host, (struct sockaddr *)&from, from_len), len, ttl);
if ((ttl != server_info->ttl) && (server_info->ttl > 0) && (server_info->result_flag & DNSSERVER_FLAG_CHECK_TTL)) {
if ((ttl < server_info->ttl - server_info->ttl_range) || (ttl > server_info->ttl + server_info->ttl_range)) {
@@ -1141,7 +1203,6 @@ static int _dns_client_process_tcp(struct dns_server_info *server_info, struct e
int len;
int ret = -1;
unsigned char *inpacket_data = server_info->recv_buff.data;
char from_host[DNS_MAX_CNAME_LEN];
if (event->events & EPOLLIN) {
/* receive from tcp */
@@ -1173,7 +1234,7 @@ static int _dns_client_process_tcp(struct dns_server_info *server_info, struct e
ret = 0;
}
pthread_mutex_unlock(&client.server_list_lock);
tlog(TLOG_DEBUG, "peer close, left = %d", server_info->send_buff.len);
tlog(TLOG_DEBUG, "peer close, %s", server_info->ip);
return ret;
}
@@ -1202,7 +1263,7 @@ static int _dns_client_process_tcp(struct dns_server_info *server_info, struct e
}
inpacket_data = server_info->recv_buff.data + 2;
tlog(TLOG_DEBUG, "recv tcp from %s, len = %d", gethost_by_addr(from_host, (struct sockaddr *)&server_info->addr, server_info->ai_addrlen), len);
tlog(TLOG_DEBUG, "recv tcp packet from %s, len = %d", server_info->ip, len);
/* process result */
if (_dns_client_recv(server_info, inpacket_data, len, &server_info->addr, server_info->ai_addrlen) != 0) {
@@ -1226,7 +1287,7 @@ static int _dns_client_process_tcp(struct dns_server_info *server_info, struct e
if (server_info->status == DNS_SERVER_STATUS_CONNECTING) {
server_info->status = DNS_SERVER_STATUS_CONNECTED;
tlog(TLOG_DEBUG, "tcp connected");
tlog(TLOG_DEBUG, "tcp server %s connected", server_info->ip);
}
if (server_info->status != DNS_SERVER_STATUS_CONNECTED) {
@@ -1361,7 +1422,7 @@ static int _dns_client_process_tls(struct dns_server_info *server_info, struct e
return 0;
}
tlog(TLOG_DEBUG, "TLS server connected.\n");
tlog(TLOG_DEBUG, "tls server %s connected.\n", server_info->ip);
/* Was the stored session reused? */
if (SSL_session_reused(server_info->ssl)) {
tlog(TLOG_DEBUG, "reused session");
@@ -1371,14 +1432,15 @@ static int _dns_client_process_tls(struct dns_server_info *server_info, struct e
SSL_SESSION_free(server_info->ssl_session);
server_info->ssl_session = NULL;
}
if (_dns_client_tls_verify(server_info) != 0) {
tlog(TLOG_WARN, "peer verify failed.");
goto errout;
}
server_info->ssl_session = SSL_get1_session(server_info->ssl);
}
if (_dns_client_tls_verify(server_info) != 0) {
tlog(TLOG_WARN, "peer verify failed.");
goto errout;
}
server_info->status = DNS_SERVER_STATUS_CONNECTED;
memset(&fd_event, 0, sizeof(fd_event));
fd_event.events = EPOLLIN | EPOLLOUT;

7
src/dns_server.c
View File

@@ -761,9 +761,9 @@ void _dns_server_ping_result(struct ping_host_struct *ping_host, const char *hos
}
if (result == PING_RESULT_RESPONSE) {
request->has_ping_result = 1;
tlog(TLOG_DEBUG, "from %15s: seq=%d time=%d\n", host, seqno, rtt);
tlog(TLOG_DEBUG, "from %s: seq=%d time=%d\n", host, seqno, rtt);
} else {
tlog(TLOG_DEBUG, "from %15s: seq=%d timeout\n", host, seqno);
tlog(TLOG_DEBUG, "from %s: seq=%d timeout\n", host, seqno);
}
if (rtt < threshold) {
@@ -1416,6 +1416,7 @@ static int _dns_server_recv(struct dns_server_conn *client, unsigned char *inpac
_dns_server_client_get(client);
tlog(TLOG_DEBUG, "recv query packet from %s, len = %d", gethost_by_addr(name, (struct sockaddr *)from, from_len), inpacket_len);
decode_len = dns_decode(packet, DNS_PACKSIZE, inpacket, inpacket_len);
if (decode_len < 0) {
tlog(TLOG_ERROR, "decode failed.\n");
@@ -1507,7 +1508,7 @@ static int _dns_server_recv(struct dns_server_conn *client, unsigned char *inpac
goto clean_exit;
}
tlog(TLOG_INFO, "query server %s from %s, qtype = %d\n", request->domain, gethost_by_addr(name, (struct sockaddr *)from, from_len), qtype);
tlog(TLOG_INFO, "query server %s from %s, qtype = %d\n", request->domain, name, qtype);
_dns_server_request_get(request);
pthread_mutex_lock(&server.request_list_lock);