package sniff import ( "context" "encoding/binary" "io" "os" "time" "github.com/sagernet/sing-box/adapter" C "github.com/sagernet/sing-box/constant" "github.com/sagernet/sing/common" "github.com/sagernet/sing/common/buf" "github.com/sagernet/sing/common/task" "golang.org/x/net/dns/dnsmessage" ) func StreamDomainNameQuery(readCtx context.Context, reader io.Reader) (*adapter.InboundContext, error) { var length uint16 err := binary.Read(reader, binary.BigEndian, &length) if err != nil { return nil, err } if length > 512 { return nil, os.ErrInvalid } _buffer := buf.StackNewSize(int(length)) defer common.KeepAlive(_buffer) buffer := common.Dup(_buffer) defer buffer.Release() readCtx, cancel := context.WithTimeout(readCtx, time.Millisecond*100) var readTask task.Group readTask.Append0(func(ctx context.Context) error { return common.Error(buffer.ReadFullFrom(reader, buffer.FreeLen())) }) err = readTask.Run(readCtx) cancel() if err != nil { return nil, err } return DomainNameQuery(readCtx, buffer.Bytes()) } func DomainNameQuery(ctx context.Context, packet []byte) (*adapter.InboundContext, error) { var parser dnsmessage.Parser _, err := parser.Start(packet) if err != nil { return nil, err } question, err := parser.Question() if err != nil { return nil, os.ErrInvalid } domain := question.Name.String() if question.Class == dnsmessage.ClassINET && IsDomainName(domain) { return &adapter.InboundContext{Protocol: C.ProtocolDNS /*, Domain: domain*/}, nil } return nil, os.ErrInvalid }