backend

type Backend ¶

type Backend struct {
	// The text the backend will serve to a successful hello message
	Banner string

	// The protocol version negotiated with the remote end
	ProtocolVersion int
	// contains filtered or unexported fields
}

func New(r io.Reader, w io.Writer, banner string) *Backend

func (b *Backend) Negotiate() error

func (b *Backend) Run(callback Callback) error

type Callback ¶

type Callback func(b *Backend, q *Query) ([]*Response, error)

A callback of this type is executed whenever a query is received. If an error is returned, the responses are ignored and the error text is returned to the backend. Otherwise, the responses are serialised and sent back in order.

type Query ¶

type Query struct {
	ProtocolVersion   int
	QName             string
	QClass            string
	QType             string
	Id                string
	RemoteIpAddress   string
	LocalIpAddress    string
	EdnsSubnetAddress string
}

Represents a query received by the backend. Certain fields may be blank, depending on negotiated protocol version - which is stored in ProtocolVersion

QName, QClass, QType, Id and RemoteIpAddress are present in all versions LocalIpAddress was added in version 2 EdnsSubnetAddress was added in version 3

func (q *Query) String() (string, error)

type Response ¶

type Response struct {
	ProtocolVersion int
	ScopeBits       string
	Auth            string
	QName           string
	QClass          string
	QType           string
	TTL             string
	Id              string
	Content         string
}

A response to be sent back in answer to a query. Again, some fields may be blank, depending on protocol version.

QName, QClass, QType, TTL, Id and Content are present in all versions No additions in version 2 ScopeBits and Auth were added in version 3

func (r *Response) String() (string, error)