feat: add comprehensive DNS handler e2e tests

Adds 22 DNS e2e subtests across 8 test methods covering: upstream
resolution (A, AAAA, multi-A), TCP mode, bypass rules, host mapper,
exchange failure (graceful error recovery), rate limiter wiring,
invalid query handling, and DNS over TLS (mode: tls).

Includes two authoritative DNS responders (UDP/TCP), a standalone
DNS query client, and a TLS DNS query script.
This commit is contained in:
ginuerzh
2026-06-27 00:21:37 +08:00
parent 590c6f48bd
commit a0427be086
13 changed files with 989 additions and 0 deletions
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package e2e
import (
"context"
"encoding/base64"
"fmt"
"io"
"strings"
"testing"
"time"
"github.com/stretchr/testify/suite"
"github.com/testcontainers/testcontainers-go"
)
type DNSSuite struct {
suite.Suite
ctx context.Context
}
func (s *DNSSuite) SetupSuite() {
s.ctx = context.Background()
}
// dnsQuery sends a DNS query via the Python client and retries on failure.
// expected can be an IP string, "empty" (expect zero answer records), or "" (no check).
func (s *DNSSuite) dnsQuery(gostC testcontainers.Container, mode, host, port, qname, qtype, expected string) {
args := []string{"python3", "/scripts/dns_query.py", mode, host, port, qname, qtype}
if expected != "" {
args = append(args, expected)
}
for i := range 5 {
code, out, err := gostC.Exec(s.ctx, args)
if err != nil {
s.T().Logf("query attempt %d exec error: %v", i+1, err)
time.Sleep(time.Second)
continue
}
body, err := io.ReadAll(out)
if err != nil {
s.T().Logf("query attempt %d read error: %v", i+1, err)
time.Sleep(time.Second)
continue
}
output := string(body)
s.T().Logf("query attempt %d: %s", i+1, strings.TrimSpace(output))
if code == 0 {
return
}
time.Sleep(time.Second)
}
s.T().Fatalf("DNS query %s %s %s %s failed after 5 retries", mode, qname, qtype, host)
}
// dnsQueryOnce sends a single DNS query with no retries. Returns exit code and output.
func (s *DNSSuite) dnsQueryOnce(gostC testcontainers.Container, mode, host, port, qname, qtype string) (int, string) {
args := []string{"python3", "/scripts/dns_query.py", mode, host, port, qname, qtype}
code, out, err := gostC.Exec(s.ctx, args)
if err != nil {
return 1, fmt.Sprintf("exec error: %v", err)
}
body, _ := io.ReadAll(out)
return code, string(body)
}
// dnsQueryWithDelay calls dnsQuery with a small wait before the first attempt.
func (s *DNSSuite) dnsQueryWithDelay(gostC testcontainers.Container, mode, host, port, qname, qtype, expected string) {
time.Sleep(500 * time.Millisecond)
s.dnsQuery(gostC, mode, host, port, qname, qtype, expected)
}
// sendRaw sends raw data via base64+nc and returns the response.
func (s *DNSSuite) sendRaw(gostC testcontainers.Container, host, port, data string) string {
encoded := base64.StdEncoding.EncodeToString([]byte(data))
cmd := []string{"sh", "-c",
fmt.Sprintf("echo %s | base64 -d | nc -w 3 -u %s %s", encoded, host, port)}
_, out, _ := gostC.Exec(s.ctx, cmd)
b, _ := io.ReadAll(out)
return string(b)
}
// startDNSResponder starts the UDP DNS responder and returns the container.
func (s *DNSSuite) startDNSResponder() testcontainers.Container {
dnsC, err := RunDNSResponderContainer(s.ctx, SharedNetworkName)
s.Require().NoError(err)
return dnsC
}
// startGostWithQueryScript starts a gost container with dns_query.py mounted.
func (s *DNSSuite) startGostWithQueryScript(yamlPath, exposedPort string) testcontainers.Container {
gostC, err := RunGostContainerWithFiles(s.ctx, SharedNetworkName,
yamlPath,
[]testcontainers.ContainerFile{
{HostFilePath: "scripts/dns_query.py", ContainerFilePath: "/scripts/dns_query.py", FileMode: 0644},
},
exposedPort)
s.Require().NoError(err)
return gostC
}
// ---------------------------------------------------------------------------
// Upstream resolution
// ---------------------------------------------------------------------------
func (s *DNSSuite) TestDNSUpstream() {
dnsC := s.startDNSResponder()
defer dnsC.Terminate(s.ctx)
gostC := s.startGostWithQueryScript("testdata/dns/server_upstream.yaml", "1053/udp")
defer gostC.Terminate(s.ctx)
s.T().Run("a-record", func(t *testing.T) {
s.dnsQueryWithDelay(gostC, "udp", "127.0.0.1", "1053", "test.example.com", "A", "10.0.0.1")
})
s.T().Run("aaaa-record", func(t *testing.T) {
s.dnsQuery(gostC, "udp", "127.0.0.1", "1053", "example.com", "AAAA", "::1")
})
s.T().Run("second-a-record", func(t *testing.T) {
s.dnsQuery(gostC, "udp", "127.0.0.1", "1053", "test2.example.com", "A", "10.0.0.2")
})
}
// ---------------------------------------------------------------------------
// TCP mode
// ---------------------------------------------------------------------------
func (s *DNSSuite) TestDNSTCP() {
s.T().Log("start TCP DNS responder container...")
dnsC, err := RunTCPDNSResponderContainer(s.ctx, SharedNetworkName)
s.Require().NoError(err)
defer dnsC.Terminate(s.ctx)
gostC := s.startGostWithQueryScript("testdata/dns/server_tcp.yaml", "1053/tcp")
defer gostC.Terminate(s.ctx)
s.dnsQueryWithDelay(gostC, "tcp", "127.0.0.1", "1053", "test.example.com", "A", "10.0.0.1")
s.dnsQuery(gostC, "tcp", "127.0.0.1", "1053", "test2.example.com", "A", "10.0.0.2")
}
// ---------------------------------------------------------------------------
// Bypass rules
// ---------------------------------------------------------------------------
func (s *DNSSuite) TestDNSBypass() {
dnsC := s.startDNSResponder()
defer dnsC.Terminate(s.ctx)
gostC := s.startGostWithQueryScript("testdata/dns/server_bypass.yaml", "1053/udp")
defer gostC.Terminate(s.ctx)
s.T().Run("blocked-domain-empty-answer", func(t *testing.T) {
s.dnsQueryWithDelay(gostC, "udp", "127.0.0.1", "1053",
"test.example.com", "A", "empty")
})
s.T().Run("non-blocked-domain", func(t *testing.T) {
s.dnsQuery(gostC, "udp", "127.0.0.1", "1053",
"test2.example.com", "A", "10.0.0.2")
})
}
// ---------------------------------------------------------------------------
// Host mapper
// ---------------------------------------------------------------------------
// TestDNSHostMapper verifies DNS resolution via the host mapper before
// reaching the upstream exchanger.
//
// Config: server_hosts.yaml maps mapped.example.com → 10.0.0.100 with no
// working upstream. The handler checks the host mapper before the exchange
// path, so mapped names resolve without needing any upstream DNS.
func (s *DNSSuite) TestDNSHostMapper() {
gostC, err := RunGostContainerWithFiles(s.ctx, SharedNetworkName,
"testdata/dns/server_hosts.yaml",
[]testcontainers.ContainerFile{
{HostFilePath: "scripts/dns_query.py", ContainerFilePath: "/scripts/dns_query.py", FileMode: 0644},
},
"1053/udp")
s.Require().NoError(err)
defer gostC.Terminate(s.ctx)
s.T().Run("mapped-a-record", func(t *testing.T) {
// mapped.example.com → host mapper returns 10.0.0.100
// without contacting any upstream.
s.dnsQueryWithDelay(gostC, "udp", "127.0.0.1", "1053",
"mapped.example.com", "A", "10.0.0.100")
})
s.T().Run("unmapped-domain", func(t *testing.T) {
// test.example.com is not in the hosts mapping. The handler
// will fall through to the exchanger path, which fails because
// no upstream is configured. Query should return empty/NXDOMAIN.
code, output := s.dnsQueryOnce(gostC, "udp", "127.0.0.1", "1053",
"test.example.com", "A")
s.T().Logf("unmapped query: code=%d, %s", code, strings.TrimSpace(output))
// Non-zero exit indicates no valid response — expected since
// there's no working upstream.
s.Assert().NotEqual(0, code,
"unmapped domain should fail with no upstream")
})
}
// ---------------------------------------------------------------------------
// Exchange failure (unreachable upstream)
// ---------------------------------------------------------------------------
// TestDNSExchangeFailure verifies graceful handling when the upstream DNS
// exchanger is unreachable.
//
// Config: server_exchange_failure.yaml points to udp://127.0.0.1:1 which
// is unreachable. The handler must not crash or leak goroutines when the
// upstream exchange fails.
func (s *DNSSuite) TestDNSExchangeFailure() {
gostC, err := RunGostContainerWithFiles(s.ctx, SharedNetworkName,
"testdata/dns/server_exchange_failure.yaml",
[]testcontainers.ContainerFile{
{HostFilePath: "scripts/dns_query.py", ContainerFilePath: "/scripts/dns_query.py", FileMode: 0644},
},
"1053/udp")
s.Require().NoError(err)
defer gostC.Terminate(s.ctx)
s.T().Run("unreachable-upstream", func(t *testing.T) {
// Send query once — the exchange will fail (timeout / ICMP
// unreachable). No response is expected.
code, output := s.dnsQueryOnce(gostC, "udp", "127.0.0.1", "1053",
"test.example.com", "A")
s.T().Logf("exchange failure result: code=%d, %s",
code, strings.TrimSpace(output))
// Non-zero exit is expected since the exchange fails.
s.Assert().NotEqual(0, code,
"exchange failure should return non-zero exit")
})
s.T().Run("container-alive-after-failure", func(t *testing.T) {
// Verify the gost container is still running after the
// failed exchange — proves no crash or hang.
aliveCode, _, aliveErr := gostC.Exec(s.ctx, []string{"true"})
s.Require().NoError(aliveErr,
"container exec should succeed after exchange failure")
s.Require().Equal(0, aliveCode,
"gost container should be alive after exchange failure")
})
}
// ---------------------------------------------------------------------------
// Rate limiter
// ---------------------------------------------------------------------------
// TestDNSRateLimiter verifies that rate limiting configuration is accepted
// and the handler processes queries through the rate limiter path without
// crashing. Uses a generous global limit (1000/s) so queries pass.
func (s *DNSSuite) TestDNSRateLimiter() {
dnsC := s.startDNSResponder()
defer dnsC.Terminate(s.ctx)
gostC, err := RunGostContainerWithFiles(s.ctx, SharedNetworkName,
"testdata/dns/server_rlimiter.yaml",
[]testcontainers.ContainerFile{
{HostFilePath: "scripts/dns_query.py", ContainerFilePath: "/scripts/dns_query.py", FileMode: 0644},
},
"1053/udp")
s.Require().NoError(err)
defer gostC.Terminate(s.ctx)
s.T().Run("query-with-limiter", func(t *testing.T) {
s.dnsQueryWithDelay(gostC, "udp", "127.0.0.1", "1053",
"test.example.com", "A", "10.0.0.1")
})
s.T().Run("second-query-with-limiter", func(t *testing.T) {
s.dnsQuery(gostC, "udp", "127.0.0.1", "1053",
"test2.example.com", "A", "10.0.0.2")
})
}
// ---------------------------------------------------------------------------
// Invalid query
// ---------------------------------------------------------------------------
// TestDNSInvalidQuery verifies the DNS listener gracefully handles malformed
// DNS messages. Sends garbage bytes and checks the gost container is
// unaffected (no crash, no hang).
func (s *DNSSuite) TestDNSInvalidQuery() {
gostC := s.startGostWithQueryScript("testdata/dns/server_upstream.yaml", "1053/udp")
defer gostC.Terminate(s.ctx)
s.T().Run("send-garbage-bytes", func(t *testing.T) {
// Send 5 bytes of garbage via UDP. The miekg/dns server
// will fail to parse them and discard the packet.
s.sendRaw(gostC, "127.0.0.1", "1053", "garbage!")
})
s.T().Run("container-alive-after-garbage", func(t *testing.T) {
// Verify the gost container is still alive after receiving
// invalid data.
aliveCode, _, aliveErr := gostC.Exec(s.ctx, []string{"true"})
s.Require().NoError(aliveErr,
"container exec should succeed after invalid query")
s.Require().Equal(0, aliveCode,
"gost container should be alive after invalid query")
})
}
// ---------------------------------------------------------------------------
// DNS over TLS
// ---------------------------------------------------------------------------
// TestDNSTLS verifies the DNS listener in TLS mode (DNS over TLS).
// Starts the UDP DNS responder (unencrypted), a gost DNS server with
// listener mode: tls, and queries through the TLS endpoint.
func (s *DNSSuite) TestDNSTLS() {
dnsC := s.startDNSResponder()
defer dnsC.Terminate(s.ctx)
gostC, err := RunGostContainerWithFiles(s.ctx, SharedNetworkName,
"testdata/dns/server_tls.yaml",
[]testcontainers.ContainerFile{
{HostFilePath: "scripts/dns_tls_query.py", ContainerFilePath: "/scripts/dns_tls_query.py", FileMode: 0644},
},
"1053/tcp")
s.Require().NoError(err)
defer gostC.Terminate(s.ctx)
// Query via TLS
args := []string{"python3", "/scripts/dns_tls_query.py",
"127.0.0.1", "1053", "test.example.com", "A", "10.0.0.1"}
for i := range 5 {
code, out, err := gostC.Exec(s.ctx, args)
if err != nil {
s.T().Logf("tls query attempt %d exec error: %v", i+1, err)
time.Sleep(time.Second)
continue
}
body, err := io.ReadAll(out)
if err != nil {
s.T().Logf("tls query attempt %d read error: %v", i+1, err)
time.Sleep(time.Second)
continue
}
output := string(body)
s.T().Logf("tls query attempt %d: %s", i+1, strings.TrimSpace(output))
if code == 0 {
return
}
time.Sleep(time.Second)
}
s.T().Fatal("TLS query failed after 5 retries")
}
func TestDNSSuite(t *testing.T) {
suite.Run(t, new(DNSSuite))
}
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"""DNS query client for e2e tests.
Usage:
python3 dns_query.py udp host port qname qtype [expected_ip|empty]
python3 dns_query.py tcp host port qname qtype [expected_ip|empty]
Sends a DNS query and optionally checks the response:
- expected_ip: verify response contains this IP address
- "empty": verify response has zero answer records (NXDOMAIN or blocked)
- omitted: exit 0 on any valid DNS response
Exits 0 on success, 1 on failure.
"""
import struct
import socket
import sys
def encode_name(name):
parts = name.rstrip(".").split(".")
return b"".join(bytes([len(p)]) + p.encode() for p in parts) + b"\x00"
def skip_name(data, pos):
"""Skip one DNS name at pos, return position after it."""
while True:
length = data[pos]
if length == 0:
return pos + 1
if length & 0xC0:
return pos + 2
pos += length + 1
def build_query(qname, qtype):
tid = 0x1234
flags = 0x0100 # RD=1
qdcount = 1
header = struct.pack(">HHHHHH", tid, flags, qdcount, 0, 0, 0)
qname_enc = encode_name(qname)
question = qname_enc + struct.pack(">HH", qtype, 1) # QTYPE, QCLASS=IN
return header + question
def parse_response(data):
if len(data) < 12:
return [], -1
flags = struct.unpack(">H", data[2:4])[0]
rcode = flags & 0x0F
qdcount = struct.unpack(">H", data[4:6])[0]
ancount = struct.unpack(">H", data[6:8])[0]
# Skip question section
pos = 12
for _ in range(qdcount):
pos = skip_name(data, pos) + 4 # QTYPE + QCLASS
answers = []
for _ in range(ancount):
pos = skip_name(data, pos)
rtype, rclass, ttl, rdlength = struct.unpack(">HHIH", data[pos:pos + 10])
pos += 10
rdata = data[pos:pos + rdlength]
pos += rdlength
answers.append((rtype, rclass, ttl, rdata))
return answers, rcode
def query_udp(host, port, query):
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.settimeout(5)
sock.sendto(query, (host, port))
data, _ = sock.recvfrom(4096)
sock.close()
return data
def query_tcp(host, port, query):
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.settimeout(5)
sock.connect((host, port))
sock.sendall(struct.pack(">H", len(query)) + query)
raw = sock.recv(2)
if len(raw) < 2:
sock.close()
return b""
msglen = struct.unpack(">H", raw)[0]
data = b""
while len(data) < msglen:
chunk = sock.recv(msglen - len(data))
if not chunk:
break
data += chunk
sock.close()
return data
def format_ip(rtype, rdata):
if rtype == 1 and len(rdata) == 4:
return socket.inet_ntoa(rdata)
if rtype == 28 and len(rdata) == 16:
return socket.inet_ntop(socket.AF_INET6, rdata)
return repr(rdata)
def main():
if len(sys.argv) < 5:
print("Usage: dns_query.py <udp|tcp> <host> <port> <qname> <qtype> [expected_ip|empty]")
sys.exit(1)
mode = sys.argv[1]
host = sys.argv[2]
port = int(sys.argv[3])
qname = sys.argv[4]
qtype_str = sys.argv[5]
expected = sys.argv[6] if len(sys.argv) > 6 else None
qtype_map = {"A": 1, "AAAA": 28}
qtype = qtype_map.get(qtype_str, 1)
query = build_query(qname, qtype)
try:
if mode == "tcp":
data = query_tcp(host, port, query)
else:
data = query_udp(host, port, query)
except Exception as e:
print(f"ERROR: {e}")
sys.exit(1)
if not data:
print("ERROR: empty response")
sys.exit(1)
answers, rcode = parse_response(data)
print(f"Got {len(answers)} answer(s), rcode={rcode}")
for rtype, _, _, rdata in answers:
print(f" {format_ip(rtype, rdata)}")
if expected == "empty":
if len(answers) == 0:
print("MATCH: empty answer (expected)")
sys.exit(0)
print(f"NO MATCH: expected empty, got {len(answers)} answers")
sys.exit(1)
elif expected:
for rtype, _, _, rdata in answers:
ip = format_ip(rtype, rdata)
if ip == expected:
print(f"MATCH: expected {expected}")
sys.exit(0)
print(f"NO MATCH: expected {expected}")
sys.exit(1)
else:
sys.exit(0)
if __name__ == "__main__":
main()
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"""Simple authoritative DNS responder for e2e tests.
Listens on UDP port 5353 and responds with static records:
test.example.com. IN A 10.0.0.1
test2.example.com. IN A 10.0.0.2
example.com. IN AAAA ::1
All other queries receive NXDOMAIN.
"""
import socketserver
import struct
import socket
def decode_name(data, offset):
labels = []
while True:
length = data[offset]
if length == 0:
offset += 1
break
if length & 0xC0:
offset += 2
break
offset += 1
labels.append(data[offset:offset + length].decode())
offset += length
return '.'.join(labels), offset
def encode_name(name):
parts = name.rstrip(".").split(".")
return b"".join(bytes([len(p)]) + p.encode() for p in parts) + b"\x00"
RECORDS = {
("test.example.com", 1): (1, 300, socket.inet_aton("10.0.0.1")),
("test2.example.com", 1): (1, 300, socket.inet_aton("10.0.0.2")),
("example.com", 28): (28, 300, socket.inet_pton(socket.AF_INET6, "::1")),
}
class DNSResponder(socketserver.DatagramRequestHandler):
def handle(self):
data = self.rfile.read(512)
if len(data) < 12:
return
tid = struct.unpack(">H", data[:2])[0]
qdcount = struct.unpack(">H", data[4:6])[0]
if qdcount == 0:
return
qname, pos = decode_name(data, 12)
qtype = struct.unpack(">H", data[pos:pos + 2])[0]
qclass = struct.unpack(">H", data[pos + 2:pos + 4])[0]
key = (qname, qtype)
if key in RECORDS:
rcode = 0
ancount = 1
rtype, ttl, rdata = RECORDS[key]
else:
rcode = 3 # NXDOMAIN
ancount = 0
rtype, ttl, rdata = 0, 0, b""
flags = 0x8000 | 0x0400 | rcode # QR=1, AA=1, rcode
header = struct.pack(">HHHHHH", tid, flags, qdcount, ancount, 0, 0)
question = data[12:pos + 4]
answer = b""
if ancount:
answer = (
struct.pack(">HH", 0xC00C, rtype) # NAME pointer + TYPE
+ struct.pack(">HI", qclass, ttl) # CLASS + TTL
+ struct.pack(">H", len(rdata)) + rdata # RDLENGTH + RDATA
)
self.wfile.write(header + question + answer)
if __name__ == "__main__":
with socketserver.UDPServer(("0.0.0.0", 5353), DNSResponder) as srv:
srv.serve_forever()
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"""Simple authoritative DNS responder for TCP mode e2e tests.
Listens on TCP port 5353 and responds with the same static records
as dns_responder.py, but over TCP (RFC 5966).
"""
import socketserver
import struct
import socket
def decode_name(data, offset):
labels = []
while True:
length = data[offset]
if length == 0:
offset += 1
break
if length & 0xC0:
offset += 2
break
offset += 1
labels.append(data[offset:offset + length].decode())
offset += length
return '.'.join(labels), offset
RECORDS = {
("test.example.com", 1): (1, 300, socket.inet_aton("10.0.0.1")),
("test2.example.com", 1): (1, 300, socket.inet_aton("10.0.0.2")),
("example.com", 28): (28, 300, socket.inet_pton(socket.AF_INET6, "::1")),
}
class DNSResponder(socketserver.StreamRequestHandler):
def handle(self):
# TCP DNS: 2-byte length prefix
raw = self.rfile.read(2)
if len(raw) < 2:
return
msglen = struct.unpack(">H", raw)[0]
data = self.rfile.read(msglen)
if len(data) < 12:
return
tid = struct.unpack(">H", data[:2])[0]
qdcount = struct.unpack(">H", data[4:6])[0]
if qdcount == 0:
return
qname, pos = decode_name(data, 12)
qtype = struct.unpack(">H", data[pos:pos + 2])[0]
qclass = struct.unpack(">H", data[pos + 2:pos + 4])[0]
key = (qname, qtype)
if key in RECORDS:
rcode = 0
ancount = 1
rtype, ttl, rdata = RECORDS[key]
else:
rcode = 3 # NXDOMAIN
ancount = 0
rtype, ttl, rdata = 0, 0, b""
flags = 0x8000 | 0x0400 | rcode
header = struct.pack(">HHHHHH", tid, flags, qdcount, ancount, 0, 0)
question = data[12:pos + 4]
answer = b""
if ancount:
answer = (
struct.pack(">HH", 0xC00C, rtype)
+ struct.pack(">HI", qclass, ttl)
+ struct.pack(">H", len(rdata)) + rdata
)
dnsmsg = header + question + answer
self.wfile.write(struct.pack(">H", len(dnsmsg)) + dnsmsg)
if __name__ == "__main__":
with socketserver.TCPServer(("0.0.0.0", 5353), DNSResponder) as srv:
srv.serve_forever()
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"""DNS query client over TLS for e2e tests.
Connects to the DNS-over-TLS endpoint and performs a DNS query.
Usage:
python3 dns_tls_query.py host port qname qtype [expected_ip]
"""
import struct
import socket
import ssl
import sys
def encode_name(name):
parts = name.rstrip(".").split(".")
return b"".join(bytes([len(p)]) + p.encode() for p in parts) + b"\x00"
def build_query(tid, qname, qtype):
flags = 0x0100
qdcount = 1
header = struct.pack(">HHHHHH", tid, flags, qdcount, 0, 0, 0)
qname_enc = encode_name(qname)
question = qname_enc + struct.pack(">HH", qtype, 1)
return header + question
def parse_response(data):
if len(data) < 12:
return [], -1
flags = struct.unpack(">H", data[2:4])[0]
rcode = flags & 0x0F
qdcount = struct.unpack(">H", data[4:6])[0]
ancount = struct.unpack(">H", data[6:8])[0]
pos = 12
for _ in range(qdcount):
while data[pos] != 0:
if data[pos] & 0xC0:
pos += 2
break
pos += data[pos] + 1
else:
pos += 1
pos += 4
answers = []
for _ in range(ancount):
if data[pos] & 0xC0:
pos += 2
else:
while data[pos] != 0:
pos += data[pos] + 1
pos += 1
rtype, rclass, ttl, rdlength = struct.unpack(">HHIH", data[pos:pos + 10])
pos += 10
rdata = data[pos:pos + rdlength]
pos += rdlength
answers.append((rtype, rdata))
return answers, rcode
def main():
if len(sys.argv) < 5:
print(f"Usage: {sys.argv[0]} host port qname qtype [expected_ip]")
sys.exit(1)
host = sys.argv[1]
port = int(sys.argv[2])
qname = sys.argv[3]
qtype_str = sys.argv[4]
expected = sys.argv[5] if len(sys.argv) > 5 else None
qtype_map = {"A": 1, "AAAA": 28}
qtype = qtype_map.get(qtype_str, 1)
query = build_query(0x1234, qname, qtype)
ctx = ssl.create_default_context()
ctx.check_hostname = False
ctx.verify_mode = ssl.CERT_NONE
try:
with socket.create_connection((host, port), timeout=5) as sock:
with ctx.wrap_socket(sock, server_hostname=host) as tls_sock:
# TCP DNS: 2-byte length prefix
tls_sock.sendall(struct.pack(">H", len(query)) + query)
raw = tls_sock.recv(2)
if len(raw) < 2:
print("ERROR: short response header")
sys.exit(1)
msglen = struct.unpack(">H", raw)[0]
data = b""
while len(data) < msglen:
chunk = tls_sock.recv(msglen - len(data))
if not chunk:
break
data += chunk
except Exception as e:
print(f"ERROR: {e}")
sys.exit(1)
if not data:
print("ERROR: empty response")
sys.exit(1)
answers, rcode = parse_response(data)
print(f"Got {len(answers)} answer(s), rcode={rcode}")
for rtype, rdata in answers:
if rtype == 1 and len(rdata) == 4:
ip = socket.inet_ntoa(rdata)
print(f" A {ip}")
elif rtype == 28 and len(rdata) == 16:
ip6 = socket.inet_ntop(socket.AF_INET6, rdata)
print(f" AAAA {ip6}")
else:
print(f" TYPE={rtype} RDATA={rdata.hex()}")
if expected:
for rtype, rdata in answers:
if rtype == 1 and len(rdata) == 4:
ip = socket.inet_ntoa(rdata)
if ip == expected:
print(f"MATCH: expected {expected}")
sys.exit(0)
elif rtype == 28 and len(rdata) == 16:
ip6 = socket.inet_ntop(socket.AF_INET6, rdata)
if ip6 == expected:
print(f"MATCH: expected {expected}")
sys.exit(0)
print(f"NO MATCH: expected {expected}")
sys.exit(1)
sys.exit(0)
if __name__ == "__main__":
main()
+16
View File
@@ -0,0 +1,16 @@
services:
- name: dns
addr: :1053
handler:
type: dns
metadata:
dns: udp://dns-server:5353
timeout: 5s
listener:
type: dns
bypass: block-example
bypasses:
- name: block-example
matchers:
- test.example.com
+10
View File
@@ -0,0 +1,10 @@
services:
- name: dns
addr: :1053
handler:
type: dns
metadata:
dns: udp://127.0.0.1:1
timeout: 2s
listener:
type: dns
+19
View File
@@ -0,0 +1,19 @@
services:
- name: dns
addr: :1053
handler:
type: dns
metadata:
# No upstream — host mapper resolves before exchanger is ever reached.
timeout: 2s
listener:
type: dns
hosts: my-hosts
hosts:
- name: my-hosts
mappings:
- ip: 10.0.0.100
hostname: mapped.example.com
- ip: 192.168.1.200
hostname: aaaa.mapped.example.com
+16
View File
@@ -0,0 +1,16 @@
services:
- name: dns
addr: :1053
handler:
type: dns
metadata:
dns: udp://dns-server:5353
timeout: 5s
listener:
type: dns
rlimiter: limiter-0
rlimiters:
- name: limiter-0
limits:
- "$ 1000"
+12
View File
@@ -0,0 +1,12 @@
services:
- name: dns
addr: :1053
handler:
type: dns
metadata:
dns: tcp://dns-server:5353
timeout: 5s
listener:
type: dns
metadata:
mode: tcp
+12
View File
@@ -0,0 +1,12 @@
services:
- name: dns
addr: :1053
handler:
type: dns
metadata:
dns: udp://dns-server:5353
timeout: 5s
listener:
type: dns
metadata:
mode: tls
+10
View File
@@ -0,0 +1,10 @@
services:
- name: dns
addr: :1053
handler:
type: dns
metadata:
dns: udp://dns-server:5353
timeout: 5s
listener:
type: dns
+64
View File
@@ -128,6 +128,70 @@ func udpEchoContainerRequest(_ context.Context, networkName string) testcontaine
}
}
// RunDNSResponderContainer starts a UDP-based DNS responder for e2e DNS tests.
// The container is registered with the network alias "dns-server".
func RunDNSResponderContainer(ctx context.Context, networkName string) (testcontainers.Container, error) {
req := testcontainers.ContainerRequest{
FromDockerfile: testcontainers.FromDockerfile{
Context: ".",
Dockerfile: "Dockerfile",
Repo: "gost-e2e",
Tag: "latest",
KeepImage: true,
BuildOptionsModifier: func(opts *client.ImageBuildOptions) {
opts.NetworkMode = "host"
},
},
Networks: []string{networkName},
NetworkAliases: map[string][]string{
networkName: {"dns-server"},
},
Files: []testcontainers.ContainerFile{
{HostFilePath: "scripts/dns_responder.py", ContainerFilePath: "/scripts/dns_server.py", FileMode: 0644},
},
ExposedPorts: []string{"5353/udp"},
Cmd: []string{"python3", "/scripts/dns_server.py"},
WaitingFor: wait.ForExposedPort().SkipInternalCheck(),
}
return testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{
ContainerRequest: req,
Started: true,
})
}
// RunTCPDNSResponderContainer starts a TCP-based DNS responder for e2e DNS tests.
// The container is registered with the network alias "dns-server".
func RunTCPDNSResponderContainer(ctx context.Context, networkName string) (testcontainers.Container, error) {
req := testcontainers.ContainerRequest{
FromDockerfile: testcontainers.FromDockerfile{
Context: ".",
Dockerfile: "Dockerfile",
Repo: "gost-e2e",
Tag: "latest",
KeepImage: true,
BuildOptionsModifier: func(opts *client.ImageBuildOptions) {
opts.NetworkMode = "host"
},
},
Networks: []string{networkName},
NetworkAliases: map[string][]string{
networkName: {"dns-server"},
},
Files: []testcontainers.ContainerFile{
{HostFilePath: "scripts/dns_responder_tcp.py", ContainerFilePath: "/scripts/dns_server.py", FileMode: 0644},
},
ExposedPorts: []string{"5353/tcp"},
Cmd: []string{"python3", "/scripts/dns_server.py"},
WaitingFor: wait.ForExposedPort(),
}
return testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{
ContainerRequest: req,
Started: true,
})
}
func RunGostContainer(ctx context.Context, networkName, yamlPath string) (testcontainers.Container, error) {
return runGostContainer(ctx, networkName, yamlPath, nil, nil, nil)
}