Xray-core/app/dispatcher/fakednssniffer.go

118 lines
3.7 KiB
Go

package dispatcher
import (
"context"
"strings"
"github.com/xtls/xray-core/common"
"github.com/xtls/xray-core/common/net"
"github.com/xtls/xray-core/common/session"
"github.com/xtls/xray-core/core"
"github.com/xtls/xray-core/features/dns"
)
// newFakeDNSSniffer Create a Fake DNS metadata sniffer
func newFakeDNSSniffer(ctx context.Context) (protocolSnifferWithMetadata, error) {
var fakeDNSEngine dns.FakeDNSEngine
err := core.RequireFeatures(ctx, func(fdns dns.FakeDNSEngine) {
fakeDNSEngine = fdns
})
if err != nil {
return protocolSnifferWithMetadata{}, err
}
if fakeDNSEngine == nil {
errNotInit := newError("FakeDNSEngine is not initialized, but such a sniffer is used").AtError()
return protocolSnifferWithMetadata{}, errNotInit
}
return protocolSnifferWithMetadata{protocolSniffer: func(ctx context.Context, bytes []byte) (SniffResult, error) {
Target := session.OutboundFromContext(ctx).Target
if Target.Network == net.Network_TCP || Target.Network == net.Network_UDP {
domainFromFakeDNS := fakeDNSEngine.GetDomainFromFakeDNS(Target.Address)
if domainFromFakeDNS != "" {
newError("fake dns got domain: ", domainFromFakeDNS, " for ip: ", Target.Address.String()).WriteToLog(session.ExportIDToError(ctx))
return &fakeDNSSniffResult{domainName: domainFromFakeDNS}, nil
}
}
if ipAddressInRangeValueI := ctx.Value(ipAddressInRange); ipAddressInRangeValueI != nil {
ipAddressInRangeValue := ipAddressInRangeValueI.(*ipAddressInRangeOpt)
if fkr0, ok := fakeDNSEngine.(dns.FakeDNSEngineRev0); ok {
inPool := fkr0.IsIPInIPPool(Target.Address)
ipAddressInRangeValue.addressInRange = &inPool
}
}
return nil, common.ErrNoClue
}, metadataSniffer: true}, nil
}
type fakeDNSSniffResult struct {
domainName string
}
func (fakeDNSSniffResult) Protocol() string {
return "fakedns"
}
func (f fakeDNSSniffResult) Domain() string {
return f.domainName
}
type fakeDNSExtraOpts int
const ipAddressInRange fakeDNSExtraOpts = 1
type ipAddressInRangeOpt struct {
addressInRange *bool
}
type DNSThenOthersSniffResult struct {
domainName string
protocolOriginalName string
}
func (f DNSThenOthersSniffResult) IsProtoSubsetOf(protocolName string) bool {
return strings.HasPrefix(protocolName, f.protocolOriginalName)
}
func (DNSThenOthersSniffResult) Protocol() string {
return "fakedns+others"
}
func (f DNSThenOthersSniffResult) Domain() string {
return f.domainName
}
func newFakeDNSThenOthers(ctx context.Context, fakeDNSSniffer protocolSnifferWithMetadata, others []protocolSnifferWithMetadata) (
protocolSnifferWithMetadata, error) { // nolint: unparam
// ctx may be used in the future
_ = ctx
return protocolSnifferWithMetadata{
protocolSniffer: func(ctx context.Context, bytes []byte) (SniffResult, error) {
ipAddressInRangeValue := &ipAddressInRangeOpt{}
ctx = context.WithValue(ctx, ipAddressInRange, ipAddressInRangeValue)
result, err := fakeDNSSniffer.protocolSniffer(ctx, bytes)
if err == nil {
return result, nil
}
if ipAddressInRangeValue.addressInRange != nil {
if *ipAddressInRangeValue.addressInRange {
for _, v := range others {
if v.metadataSniffer || bytes != nil {
if result, err := v.protocolSniffer(ctx, bytes); err == nil {
return DNSThenOthersSniffResult{domainName: result.Domain(), protocolOriginalName: result.Protocol()}, nil
}
}
}
return nil, common.ErrNoClue
}
newError("ip address not in fake dns range, return as is").AtDebug().WriteToLog()
return nil, common.ErrNoClue
}
newError("fake dns sniffer did not set address in range option, assume false.").AtWarning().WriteToLog()
return nil, common.ErrNoClue
},
metadataSniffer: false,
}, nil
}