package sniffer import ( "errors" "github.com/Dreamacro/clash/constant/sniffer" "net" "net/netip" "strconv" "time" "github.com/Dreamacro/clash/component/trie" CN "github.com/Dreamacro/clash/common/net" "github.com/Dreamacro/clash/common/utils" "github.com/Dreamacro/clash/component/resolver" C "github.com/Dreamacro/clash/constant" "github.com/Dreamacro/clash/log" ) var ( ErrorUnsupportedSniffer = errors.New("unsupported sniffer") ErrorSniffFailed = errors.New("all sniffer failed") ErrNoClue = errors.New("not enough information for making a decision") ) var Dispatcher SnifferDispatcher type ( SnifferDispatcher struct { enable bool sniffers []sniffer.Sniffer foreDomain *trie.DomainTrie[bool] skipSNI *trie.DomainTrie[bool] portRanges *[]utils.Range[uint16] } ) func (sd *SnifferDispatcher) TCPSniff(conn net.Conn, metadata *C.Metadata) { bufConn, ok := conn.(*CN.BufferedConn) if !ok { return } if metadata.Host == "" || sd.foreDomain.Search(metadata.Host) != nil { port, err := strconv.ParseUint(metadata.DstPort, 10, 16) if err != nil { log.Debugln("[Sniffer] Dst port is error") return } inWhitelist := false for _, portRange := range *sd.portRanges { if portRange.Contains(uint16(port)) { inWhitelist = true break } } if !inWhitelist { return } if host, err := sd.sniffDomain(bufConn, metadata); err != nil { log.Debugln("[Sniffer] All sniffing sniff failed with from [%s:%s] to [%s:%s]", metadata.SrcIP, metadata.SrcPort, metadata.String(), metadata.DstPort) return } else { if sd.skipSNI.Search(host) != nil { log.Debugln("[Sniffer] Skip sni[%s]", host) return } sd.replaceDomain(metadata, host) } } } func (sd *SnifferDispatcher) replaceDomain(metadata *C.Metadata, host string) { log.Debugln("[Sniffer] Sniff TCP [%s:%s]-->[%s:%s] success, replace domain [%s]-->[%s]", metadata.SrcIP, metadata.SrcPort, metadata.DstIP, metadata.DstPort, metadata.Host, host) metadata.AddrType = C.AtypDomainName metadata.Host = host metadata.DNSMode = C.DNSMapping resolver.InsertHostByIP(metadata.DstIP, host) } func (sd *SnifferDispatcher) Enable() bool { return sd.enable } func (sd *SnifferDispatcher) sniffDomain(conn *CN.BufferedConn, metadata *C.Metadata) (string, error) { for _, sniffer := range sd.sniffers { if sniffer.SupportNetwork() == C.TCP { _ = conn.SetReadDeadline(time.Now().Add(3 * time.Second)) _, err := conn.Peek(1) _ = conn.SetReadDeadline(time.Time{}) if err != nil { _, ok := err.(*net.OpError) if ok { log.Errorln("[Sniffer] [%s] may not have any sent data, Consider adding skip", metadata.DstIP.String()) _ = conn.Close() } return "", err } bufferedLen := conn.Buffered() bytes, err := conn.Peek(bufferedLen) if err != nil { log.Debugln("[Sniffer] the data length not enough") continue } host, err := sniffer.SniffTCP(bytes) if err != nil { log.Debugln("[Sniffer] [%s] Sniff data failed %s", sniffer.Protocol(), metadata.DstIP) continue } _, err = netip.ParseAddr(host) if err == nil { log.Debugln("[Sniffer] [%s] Sniff data failed %s", sniffer.Protocol(), metadata.DstIP) continue } return host, nil } } return "", ErrorSniffFailed } func NewCloseSnifferDispatcher() (*SnifferDispatcher, error) { dispatcher := SnifferDispatcher{ enable: false, } return &dispatcher, nil } func NewSnifferDispatcher(needSniffer []sniffer.Type, forceDomain *trie.DomainTrie[bool], skipSNI *trie.DomainTrie[bool], ports *[]utils.Range[uint16]) (*SnifferDispatcher, error) { dispatcher := SnifferDispatcher{ enable: true, foreDomain: forceDomain, skipSNI: skipSNI, portRanges: ports, } for _, snifferName := range needSniffer { sniffer, err := NewSniffer(snifferName) if err != nil { log.Errorln("Sniffer name[%s] is error", snifferName) return &SnifferDispatcher{enable: false}, err } dispatcher.sniffers = append(dispatcher.sniffers, sniffer) } return &dispatcher, nil } func NewSniffer(name sniffer.Type) (sniffer.Sniffer, error) { switch name { case sniffer.TLS: return &TLSSniffer{}, nil case sniffer.HTTP: return &HTTPSniffer{}, nil default: return nil, ErrorUnsupportedSniffer } }