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Merged
RPRX merged 5 commits into from
Mar 24, 2025
Merged

DNS: Support returning upstream TTL to clients #4526

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d02467f
DNS: Support returning upstream TTL to clients
Meo597 Mar 21, 2025
adf33c9
Fix test
Meo597 Mar 21, 2025
4a4eaa2
Fix test TestIPIfNonMatchDomain
Meo597 Mar 21, 2025
d2f10db
Fix queryStrategy 4+6
Meo597 Mar 21, 2025
beb52a8
Merge branch 'main' into dns-ttl
Meo597 Mar 23, 2025
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19 changes: 10 additions & 9 deletions app/dns/dns.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -157,16 +157,16 @@ func (s *DNS) IsOwnLink(ctx context.Context) bool {
}

// LookupIP implements dns.Client.
func (s *DNS) LookupIP(domain string, option dns.IPOption) ([]net.IP, error) {
func (s *DNS) LookupIP(domain string, option dns.IPOption) ([]net.IP, uint32, error) {
if domain == "" {
return nil, errors.New("empty domain name")
return nil, 0, errors.New("empty domain name")
}

option.IPv4Enable = option.IPv4Enable && s.ipOption.IPv4Enable
option.IPv6Enable = option.IPv6Enable && s.ipOption.IPv6Enable

if !option.IPv4Enable && !option.IPv6Enable {
return nil, dns.ErrEmptyResponse
return nil, 0, dns.ErrEmptyResponse
}

// Normalize the FQDN form query
Expand All @@ -177,13 +177,14 @@ func (s *DNS) LookupIP(domain string, option dns.IPOption) ([]net.IP, error) {
case addrs == nil: // Domain not recorded in static host
break
case len(addrs) == 0: // Domain recorded, but no valid IP returned (e.g. IPv4 address with only IPv6 enabled)
return nil, dns.ErrEmptyResponse
return nil, 0, dns.ErrEmptyResponse
case len(addrs) == 1 && addrs[0].Family().IsDomain(): // Domain replacement
errors.LogInfo(s.ctx, "domain replaced: ", domain, " -> ", addrs[0].Domain())
domain = addrs[0].Domain()
default: // Successfully found ip records in static host
errors.LogInfo(s.ctx, "returning ", len(addrs), " IP(s) for domain ", domain, " -> ", addrs)
return toNetIP(addrs)
ips, err := toNetIP(addrs)
return ips, 10, err // Hosts ttl is 10
}

// Name servers lookup
Expand All @@ -194,21 +195,21 @@ func (s *DNS) LookupIP(domain string, option dns.IPOption) ([]net.IP, error) {
errors.LogDebug(s.ctx, "skip DNS resolution for domain ", domain, " at server ", client.Name())
continue
}
ips, err := client.QueryIP(ctx, domain, option, s.disableCache)
ips, ttl, err := client.QueryIP(ctx, domain, option, s.disableCache)
if len(ips) > 0 {
return ips, nil
return ips, ttl, nil
}
if err != nil {
errors.LogInfoInner(s.ctx, err, "failed to lookup ip for domain ", domain, " at server ", client.Name())
errs = append(errs, err)
}
// 5 for RcodeRefused in miekg/dns, hardcode to reduce binary size
if err != context.Canceled && err != context.DeadlineExceeded && err != errExpectedIPNonMatch && err != dns.ErrEmptyResponse && dns.RCodeFromError(err) != 5 {
return nil, err
return nil, 0, err
}
}

return nil, errors.New("returning nil for domain ", domain).Base(errors.Combine(errs...))
return nil, 0, errors.New("returning nil for domain ", domain).Base(errors.Combine(errs...))
}

// LookupHosts implements dns.HostsLookup.
Expand Down
44 changes: 22 additions & 22 deletions app/dns/dns_test.go
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Original file line number Diff line number Diff line change
Expand Up @@ -155,7 +155,7 @@ func TestUDPServerSubnet(t *testing.T) {

client := v.GetFeature(feature_dns.ClientType()).(feature_dns.Client)

ips, err := client.LookupIP("google.com", feature_dns.IPOption{
ips, _, err := client.LookupIP("google.com", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand Down Expand Up @@ -216,7 +216,7 @@ func TestUDPServer(t *testing.T) {
client := v.GetFeature(feature_dns.ClientType()).(feature_dns.Client)

{
ips, err := client.LookupIP("google.com", feature_dns.IPOption{
ips, _, err := client.LookupIP("google.com", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand All @@ -231,7 +231,7 @@ func TestUDPServer(t *testing.T) {
}

{
ips, err := client.LookupIP("facebook.com", feature_dns.IPOption{
ips, _, err := client.LookupIP("facebook.com", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand All @@ -246,7 +246,7 @@ func TestUDPServer(t *testing.T) {
}

{
_, err := client.LookupIP("notexist.google.com", feature_dns.IPOption{
_, _, err := client.LookupIP("notexist.google.com", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand All @@ -260,7 +260,7 @@ func TestUDPServer(t *testing.T) {
}

{
ips, err := client.LookupIP("ipv4only.google.com", feature_dns.IPOption{
ips, _, err := client.LookupIP("ipv4only.google.com", feature_dns.IPOption{
IPv4Enable: false,
IPv6Enable: true,
FakeEnable: false,
Expand All @@ -276,7 +276,7 @@ func TestUDPServer(t *testing.T) {
dnsServer.Shutdown()

{
ips, err := client.LookupIP("google.com", feature_dns.IPOption{
ips, _, err := client.LookupIP("google.com", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand Down Expand Up @@ -357,7 +357,7 @@ func TestPrioritizedDomain(t *testing.T) {
startTime := time.Now()

{
ips, err := client.LookupIP("google.com", feature_dns.IPOption{
ips, _, err := client.LookupIP("google.com", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand Down Expand Up @@ -423,7 +423,7 @@ func TestUDPServerIPv6(t *testing.T) {

client := v.GetFeature(feature_dns.ClientType()).(feature_dns.Client)
{
ips, err := client.LookupIP("ipv6.google.com", feature_dns.IPOption{
ips, _, err := client.LookupIP("ipv6.google.com", feature_dns.IPOption{
IPv4Enable: false,
IPv6Enable: true,
FakeEnable: false,
Expand Down Expand Up @@ -492,7 +492,7 @@ func TestStaticHostDomain(t *testing.T) {
client := v.GetFeature(feature_dns.ClientType()).(feature_dns.Client)

{
ips, err := client.LookupIP("example.com", feature_dns.IPOption{
ips, _, err := client.LookupIP("example.com", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand Down Expand Up @@ -603,7 +603,7 @@ func TestIPMatch(t *testing.T) {
startTime := time.Now()

{
ips, err := client.LookupIP("google.com", feature_dns.IPOption{
ips, _, err := client.LookupIP("google.com", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand Down Expand Up @@ -726,7 +726,7 @@ func TestLocalDomain(t *testing.T) {
startTime := time.Now()

{ // Will match dotless:
ips, err := client.LookupIP("hostname", feature_dns.IPOption{
ips, _, err := client.LookupIP("hostname", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand All @@ -741,7 +741,7 @@ func TestLocalDomain(t *testing.T) {
}

{ // Will match domain:local
ips, err := client.LookupIP("hostname.local", feature_dns.IPOption{
ips, _, err := client.LookupIP("hostname.local", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand All @@ -756,7 +756,7 @@ func TestLocalDomain(t *testing.T) {
}

{ // Will match static ip
ips, err := client.LookupIP("hostnamestatic", feature_dns.IPOption{
ips, _, err := client.LookupIP("hostnamestatic", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand All @@ -771,7 +771,7 @@ func TestLocalDomain(t *testing.T) {
}

{ // Will match domain replacing
ips, err := client.LookupIP("hostnamealias", feature_dns.IPOption{
ips, _, err := client.LookupIP("hostnamealias", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand All @@ -786,7 +786,7 @@ func TestLocalDomain(t *testing.T) {
}

{ // Will match dotless:localhost, but not expectIPs: 127.0.0.2, 127.0.0.3, then matches at dotless:
ips, err := client.LookupIP("localhost", feature_dns.IPOption{
ips, _, err := client.LookupIP("localhost", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand All @@ -801,7 +801,7 @@ func TestLocalDomain(t *testing.T) {
}

{ // Will match dotless:localhost, and expectIPs: 127.0.0.2, 127.0.0.3
ips, err := client.LookupIP("localhost-a", feature_dns.IPOption{
ips, _, err := client.LookupIP("localhost-a", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand All @@ -816,7 +816,7 @@ func TestLocalDomain(t *testing.T) {
}

{ // Will match dotless:localhost, and expectIPs: 127.0.0.2, 127.0.0.3
ips, err := client.LookupIP("localhost-b", feature_dns.IPOption{
ips, _, err := client.LookupIP("localhost-b", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand All @@ -831,7 +831,7 @@ func TestLocalDomain(t *testing.T) {
}

{ // Will match dotless:
ips, err := client.LookupIP("Mijia Cloud", feature_dns.IPOption{
ips, _, err := client.LookupIP("Mijia Cloud", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand Down Expand Up @@ -997,7 +997,7 @@ func TestMultiMatchPrioritizedDomain(t *testing.T) {
startTime := time.Now()

{ // Will match server 1,2 and server 1 returns expected ip
ips, err := client.LookupIP("google.com", feature_dns.IPOption{
ips, _, err := client.LookupIP("google.com", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand All @@ -1012,7 +1012,7 @@ func TestMultiMatchPrioritizedDomain(t *testing.T) {
}

{ // Will match server 1,2 and server 1 returns unexpected ip, then server 2 returns expected one
ips, err := client.LookupIP("ipv6.google.com", feature_dns.IPOption{
ips, _, err := client.LookupIP("ipv6.google.com", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: false,
FakeEnable: false,
Expand All @@ -1027,7 +1027,7 @@ func TestMultiMatchPrioritizedDomain(t *testing.T) {
}

{ // Will match server 3,1,2 and server 3 returns expected one
ips, err := client.LookupIP("api.google.com", feature_dns.IPOption{
ips, _, err := client.LookupIP("api.google.com", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand All @@ -1042,7 +1042,7 @@ func TestMultiMatchPrioritizedDomain(t *testing.T) {
}

{ // Will match server 4,3,1,2 and server 4 returns expected one
ips, err := client.LookupIP("v2.api.google.com", feature_dns.IPOption{
ips, _, err := client.LookupIP("v2.api.google.com", feature_dns.IPOption{
IPv4Enable: true,
IPv6Enable: true,
FakeEnable: false,
Expand Down
9 changes: 5 additions & 4 deletions app/dns/dnscommon.go
View file
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Original file line number Diff line number Diff line change
Expand Up @@ -38,14 +38,15 @@ type IPRecord struct {
RawHeader *dnsmessage.Header
}

func (r *IPRecord) getIPs() ([]net.Address, error) {
func (r *IPRecord) getIPs() ([]net.Address, uint32, error) {
if r == nil || r.Expire.Before(time.Now()) {
return nil, errRecordNotFound
return nil, 0, errRecordNotFound
}
if r.RCode != dnsmessage.RCodeSuccess {
return nil, dns_feature.RCodeError(r.RCode)
return nil, 0, dns_feature.RCodeError(r.RCode)
}
return r.IP, nil
ttl := uint32(time.Until(r.Expire) / time.Second)
return r.IP, ttl, nil
}

func isNewer(baseRec *IPRecord, newRec *IPRecord) bool {
Expand Down
11 changes: 6 additions & 5 deletions app/dns/nameserver.go
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Original file line number Diff line number Diff line change
Expand Up @@ -21,7 +21,7 @@ type Server interface {
// Name of the Client.
Name() string
// QueryIP sends IP queries to its configured server.
QueryIP(ctx context.Context, domain string, clientIP net.IP, option dns.IPOption, disableCache bool) ([]net.IP, error)
QueryIP(ctx context.Context, domain string, clientIP net.IP, option dns.IPOption, disableCache bool) ([]net.IP, uint32, error)
}

// Client is the interface for DNS client.
Expand Down Expand Up @@ -191,7 +191,7 @@ func (c *Client) Name() string {
}

// QueryIP sends DNS query to the name server with the client's IP.
func (c *Client) QueryIP(ctx context.Context, domain string, option dns.IPOption, disableCache bool) ([]net.IP, error) {
func (c *Client) QueryIP(ctx context.Context, domain string, option dns.IPOption, disableCache bool) ([]net.IP, uint32, error) {
ctx, cancel := context.WithTimeout(ctx, c.timeoutMs)
if len(c.tag) != 0 {
content := session.InboundFromContext(ctx)
Expand All @@ -200,13 +200,14 @@ func (c *Client) QueryIP(ctx context.Context, domain string, option dns.IPOption
// do not direct set *content.Tag, it might be used by other clients
ctx = session.ContextWithInbound(ctx, &session.Inbound{Tag: c.tag})
}
ips, err := c.server.QueryIP(ctx, domain, c.clientIP, option, disableCache)
ips, ttl, err := c.server.QueryIP(ctx, domain, c.clientIP, option, disableCache)
cancel()

if err != nil {
return ips, err
return ips, ttl, err
}
return c.MatchExpectedIPs(domain, ips)
netips, err := c.MatchExpectedIPs(domain, ips)
return netips, ttl, err
}

// MatchExpectedIPs matches queried domain IPs with expected IPs and returns matched ones.
Expand Down
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