daxi20/smartdns
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

dns_client: retry when upstream result is empty.

Browse Source
This commit is contained in:
Nick Peng
2023-12-19 22:29:44 +08:00
parent a19ac7eb07
commit 1d46fa6208
8 changed files with 209 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
src/Makefile
View File

@@ -50,9 +50,9 @@ override CXXFLAGS +=-Iinclude
# ldflags
ifeq ($(STATIC), yes)
override LDFLAGS += -lssl -lcrypto -Wl,--whole-archive -lpthread -Wl,--no-whole-archive -ldl -static
override LDFLAGS += -lssl -lcrypto -Wl,--whole-archive -lpthread -Wl,--no-whole-archive -ldl -lm -static
else
override LDFLAGS += -lssl -lcrypto -lpthread -ldl
override LDFLAGS += -lssl -lcrypto -lpthread -ldl -lm
endif
.PHONY: all clean

26
src/dns_client.c
View File

@@ -1674,6 +1674,26 @@ static int _dns_replied_check_add(struct dns_query_struct *dns_query, struct soc
return 0;
}
static void _dns_replied_check_remove(struct dns_query_struct *dns_query, struct sockaddr *addr, socklen_t addr_len)
{
uint32_t key = 0;
struct dns_query_replied *replied_map = NULL;
if (addr_len > sizeof(struct sockaddr_in6)) {
return;
}
key = jhash(addr, addr_len, 0);
hash_for_each_possible(dns_query->replied_map, replied_map, node, key)
{
if (memcmp(&replied_map->addr, addr, addr_len) == 0) {
hash_del(&replied_map->node);
free(replied_map);
return;
}
}
}
static int _dns_client_recv(struct dns_server_info *server_info, unsigned char *inpacket, int inpacket_len,
struct sockaddr *from, socklen_t from_len)
{
@@ -1761,13 +1781,17 @@ static int _dns_client_recv(struct dns_server_info *server_info, unsigned char *
if (query->callback) {
ret = query->callback(query->domain, DNS_QUERY_RESULT, server_info, packet, inpacket, inpacket_len,
query->user_ptr);
if (request_num == 0 || ret) {
if (request_num == 0 && ret == 0) {
/* if all server replied, or done, stop query, release resource */
_dns_client_query_remove(query);
}
if (ret == 0) {
query->has_result = 1;
} else {
/* remove this result */
_dns_replied_check_remove(query, from, from_len);
atomic_inc(&query->dns_request_sent);
}
}

16
src/dns_server.c
View File

@@ -3288,6 +3288,7 @@ static int _dns_server_process_answer(struct dns_request *request, const char *d
struct dns_rrs *rrs = NULL;
int ret = 0;
int is_skip = 0;
int has_result = 0;
if (packet->head.rcode != DNS_RC_NOERROR && packet->head.rcode != DNS_RC_NXDOMAIN) {
if (request->rcode == DNS_RC_SERVFAIL) {
@@ -3302,6 +3303,7 @@ static int _dns_server_process_answer(struct dns_request *request, const char *d
for (j = 1; j < DNS_RRS_OPT; j++) {
rrs = dns_get_rrs_start(packet, j, &rr_count);
for (i = 0; i < rr_count && rrs; i++, rrs = dns_get_rrs_next(packet, rrs)) {
has_result = 1;
switch (rrs->type) {
case DNS_T_A: {
ret = _dns_server_process_answer_A(rrs, request, domain, cname, result_flag);
@@ -3380,6 +3382,12 @@ static int _dns_server_process_answer(struct dns_request *request, const char *d
request->rcode = packet->head.rcode;
}
if (has_result == 0 && request->rcode == DNS_RC_NOERROR) {
tlog(TLOG_DEBUG, "no result, %s qtype: %d, rcode: %d, id: %d, retry", domain, request->qtype,
packet->head.rcode, packet->head.id);
return -1;
}
return 0;
}
@@ -3788,9 +3796,9 @@ static int dns_server_resolve_callback(const char *domain, dns_result_type rtype
}
if (rtype == DNS_QUERY_RESULT) {
tlog(TLOG_DEBUG, "query result from server %s:%d, type: %d, rcode: %d, id: %d",
tlog(TLOG_DEBUG, "query result from server %s:%d, type: %d, domain: %s qtype: %d rcode: %d, id: %d",
dns_client_get_server_ip(server_info), dns_client_get_server_port(server_info),
dns_client_get_server_type(server_info), packet->head.rcode, request->id);
dns_client_get_server_type(server_info), domain, request->qtype, packet->head.rcode, request->id);
if (request->passthrough == 1 && atomic_read(&request->notified) == 0) {
struct dns_server_post_context context;
@@ -3837,9 +3845,9 @@ static int dns_server_resolve_callback(const char *domain, dns_result_type rtype
}
}
_dns_server_process_answer(request, domain, packet, result_flag);
ret = _dns_server_process_answer(request, domain, packet, result_flag);
_dns_server_passthrough_may_complete(request);
return 0;
return ret;
} else if (rtype == DNS_QUERY_ERR) {
tlog(TLOG_ERROR, "request failed, %s", domain);
return -1;

48
test/cases/test-cache.cc
View File

@@ -455,4 +455,52 @@ cache-persist yes
server.Stop();
usleep(200 * 1000);
}
}
TEST_F(Cache, cname)
{
smartdns::MockServer server_upstream;
smartdns::Server server;
server_upstream.Start("udp://0.0.0.0:61053", [](struct smartdns::ServerRequestContext *request) {
std::string domain = request->domain;
std::string cname = "cname." + domain;
if (request->qtype != DNS_T_A) {
return smartdns::SERVER_REQUEST_SOA;
}
unsigned char addr[4] = {1, 2, 3, 4};
dns_add_domain(request->response_packet, domain.c_str(), DNS_T_A, DNS_C_IN);
dns_add_CNAME(request->response_packet, DNS_RRS_AN, domain.c_str(), 300, cname.c_str());
dns_add_A(request->response_packet, DNS_RRS_AN, cname.c_str(), 300, addr);
request->response_packet->head.rcode = DNS_RC_NOERROR;
return smartdns::SERVER_REQUEST_OK;
});
server.Start(R"""(bind [::]:60053
server 127.0.0.1:61053
log-num 0
cache-size 100
log-console 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.GetAnswerNum(), 2);
EXPECT_EQ(client.GetStatus(), "NOERROR");
EXPECT_EQ(client.GetAnswer()[0].GetName(), "a.com");
EXPECT_GE(client.GetAnswer()[0].GetTTL(), 3);
EXPECT_EQ(client.GetAnswer()[0].GetData(), "cname.a.com.");
EXPECT_EQ(client.GetAnswer()[1].GetName(), "cname.a.com");
EXPECT_GE(client.GetAnswer()[1].GetTTL(), 3);
EXPECT_EQ(client.GetAnswer()[1].GetData(), "1.2.3.4");
ASSERT_TRUE(client.Query("cname.a.com A", 60053));
std::cout << client.GetResult() << std::endl;
ASSERT_EQ(client.GetAnswerNum(), 1);
EXPECT_EQ(client.GetStatus(), "NOERROR");
EXPECT_EQ(client.GetAnswer()[0].GetName(), "cname.a.com");
EXPECT_GE(client.GetAnswer()[0].GetTTL(), 3);
EXPECT_EQ(client.GetAnswer()[0].GetData(), "1.2.3.4");
}

55
test/cases/test-dualstack.cc
View File

@@ -134,7 +134,7 @@ cache-persist no)""");
EXPECT_EQ(client.GetAnswer()[1].GetData(), "2001:db8::2");
}
TEST_F(DualStack, ipv6_prefer_must_exist_ipv4)
TEST_F(DualStack, ipv6_prefer_without_ipv4)
{
smartdns::MockServer server_upstream;
smartdns::Server server;
@@ -232,4 +232,55 @@ cache-persist no)""");
EXPECT_EQ(client.GetAuthority()[0].GetName(), "a.com");
EXPECT_GT(client.GetAuthority()[0].GetTTL(), 597);
EXPECT_EQ(client.GetAuthority()[0].GetType(), "SOA");
}
}
TEST_F(DualStack, ipv4_no_response)
{
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_NO_RESPONSE;
} 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, 10000);
server.MockPing(PING_TYPE_ICMP, "5.6.7.8", 60, 10000);
server.MockPing(PING_TYPE_ICMP, "2001:db8::1", 60, 100);
server.MockPing(PING_TYPE_ICMP, "2001:db8::2", 60, 110);
server.Start(R"""(bind [::]:60053
server 127.0.0.1:61053
log-num 0
log-console yes
dualstack-ip-selection yes
speed-check-mode ping
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.GetAnswerNum(), 0);
EXPECT_EQ(client.GetStatus(), "SERVFAIL");
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(), 590);
EXPECT_EQ(client.GetAnswer()[0].GetData(), "2001:db8::1");
EXPECT_EQ(client.GetAnswer()[1].GetName(), "a.com");
EXPECT_GT(client.GetAnswer()[1].GetTTL(), 590);
EXPECT_EQ(client.GetAnswer()[1].GetData(), "2001:db8::2");
}

66
test/cases/test-server.cc
View File

@@ -104,3 +104,69 @@ cache-persist no)""");
EXPECT_EQ(client.GetAnswer()[0].GetName(), "a.com");
EXPECT_EQ(client.GetAnswer()[0].GetData(), "1.2.3.4");
}
TEST_F(Server, retry_no_result_with_NOERROR)
{
smartdns::MockServer server_upstream;
smartdns::MockServer server_upstream1;
smartdns::Server server;
int count = 0;
server_upstream.Start("udp://0.0.0.0:61053", [&](struct smartdns::ServerRequestContext *request) {
if (request->qtype != DNS_T_A) {
return smartdns::SERVER_REQUEST_SOA;
}
if (count++ < 2) {
dns_add_domain(request->response_packet, request->domain.c_str(), request->qtype, request->qclass);
return smartdns::SERVER_REQUEST_OK;
}
smartdns::MockServer::AddIP(request, request->domain.c_str(), "1.2.3.4", 611);
return smartdns::SERVER_REQUEST_OK;
});
server.Start(R"""(bind [::]:60053
bind-tcp [::]:60053
server 127.0.0.1:61053
log-num 0
log-console yes
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_EQ(client.GetAnswer()[0].GetName(), "a.com");
EXPECT_EQ(client.GetAnswer()[0].GetData(), "1.2.3.4");
}
TEST_F(Server, retry_no_response)
{
smartdns::MockServer server_upstream;
smartdns::MockServer server_upstream1;
smartdns::Server server;
int count = 0;
server_upstream.Start("udp://0.0.0.0:61053", [&](struct smartdns::ServerRequestContext *request) {
count++;
return smartdns::SERVER_REQUEST_NO_RESPONSE;
});
server.Start(R"""(bind [::]:60053
bind-tcp [::]:60053
server 127.0.0.1:61053
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(), 0);
EXPECT_EQ(client.GetStatus(), "SERVFAIL");
EXPECT_GE(client.GetQueryTime(), 1500);
EXPECT_GE(count, 8);
}

2
test/server.cc
View File

@@ -153,6 +153,8 @@ void MockServer::Run()
dns_add_domain(request.response_packet, request.domain.c_str(), request.qtype, request.qclass);
request.response_data_len =
dns_encode(request.response_data, request.response_data_max_len, request.response_packet);
} else if (callback_ret == SERVER_REQUEST_NO_RESPONSE) {
continue;
} else if (request.response_data_len == 0) {
if (callback_ret == SERVER_REQUEST_OK) {
request.response_data_len =

1
test/server.h
View File

@@ -87,6 +87,7 @@ struct ServerRequestContext {
typedef enum {
SERVER_REQUEST_OK = 0,
SERVER_REQUEST_ERROR,
SERVER_REQUEST_NO_RESPONSE,
SERVER_REQUEST_SOA,
} ServerRequestResult;