Cleanup: put middleware helper functions in pkgs (#245)

Move all (almost all) Go files in middleware into their
own packages. This makes for better naming and discoverability.

Lot of changes elsewhere to make this change.

The middleware.State was renamed to request.Request which is better,
but still does not cover all use-cases. It was also moved out middleware
because it is used by `dnsserver` as well.

A pkg/dnsutil packages was added for shared, handy, dns util functions.

All normalize functions are now put in normalize.go

1 files changed, 0 insertions, 229 deletions

diff --git a/middleware/state.go b/middleware/state.go
deleted file mode 100644
index 4299641ab..000000000
--- a/middleware/state.go
+++ /dev/null
@@ -1,229 +0,0 @@
-package middleware
-
-import (
-	"net"
-	"strings"
-	"time"
-
-	"github.com/miekg/dns"
-)
-
-// This file contains the state functions available for use in the middlewares.
-
-// State contains some connection state and is useful in middleware.
-type State struct {
-	Req *dns.Msg
-	W   dns.ResponseWriter
-
-	// Cache size after first call to Size or Do.
-	size int
-	do   int // 0: not, 1: true: 2: false
-	// TODO(miek): opt record itself as well.
-
-	// Cache name as (lowercase) well
-	name string
-}
-
-// Now returns the current timestamp in the specified format.
-func (s *State) Now(format string) string { return time.Now().Format(format) }
-
-// NowDate returns the current date/time that can be used in other time functions.
-func (s *State) NowDate() time.Time { return time.Now() }
-
-// IP gets the (remote) IP address of the client making the request.
-func (s *State) IP() string {
-	ip, _, err := net.SplitHostPort(s.W.RemoteAddr().String())
-	if err != nil {
-		return s.W.RemoteAddr().String()
-	}
-	return ip
-}
-
-// Post gets the (remote) Port of the client making the request.
-func (s *State) Port() (string, error) {
-	_, port, err := net.SplitHostPort(s.W.RemoteAddr().String())
-	if err != nil {
-		return "0", err
-	}
-	return port, nil
-}
-
-// RemoteAddr returns the net.Addr of the client that sent the current request.
-func (s *State) RemoteAddr() string {
-	return s.W.RemoteAddr().String()
-}
-
-// Proto gets the protocol used as the transport. This will be udp or tcp.
-func (s *State) Proto() string { return Proto(s.W) }
-
-// Proto gets the protocol used as the transport. This will be udp or tcp.
-func Proto(w dns.ResponseWriter) string {
-	if _, ok := w.RemoteAddr().(*net.UDPAddr); ok {
-		return "udp"
-	}
-	if _, ok := w.RemoteAddr().(*net.TCPAddr); ok {
-		return "tcp"
-	}
-	return "udp"
-}
-
-// Family returns the family of the transport.
-// 1 for IPv4 and 2 for IPv6.
-func (s *State) Family() int {
-	var a net.IP
-	ip := s.W.RemoteAddr()
-	if i, ok := ip.(*net.UDPAddr); ok {
-		a = i.IP
-	}
-	if i, ok := ip.(*net.TCPAddr); ok {
-		a = i.IP
-	}
-
-	if a.To4() != nil {
-		return 1
-	}
-	return 2
-}
-
-// Do returns if the request has the DO (DNSSEC OK) bit set.
-func (s *State) Do() bool {
-	if s.do != 0 {
-		return s.do == doTrue
-	}
-
-	if o := s.Req.IsEdns0(); o != nil {
-		if o.Do() {
-			s.do = doTrue
-		} else {
-			s.do = doFalse
-		}
-		return o.Do()
-	}
-	s.do = doFalse
-	return false
-}
-
-// UDPSize returns if UDP buffer size advertised in the requests OPT record.
-// Or when the request was over TCP, we return the maximum allowed size of 64K.
-func (s *State) Size() int {
-	if s.size != 0 {
-		return s.size
-	}
-
-	size := 0
-	if o := s.Req.IsEdns0(); o != nil {
-		if o.Do() == true {
-			s.do = doTrue
-		} else {
-			s.do = doFalse
-		}
-		size = int(o.UDPSize())
-	}
-	size = edns0Size(s.Proto(), size)
-	s.size = size
-	return size
-}
-
-// SizeAndDo adds an OPT record that the reflects the intent from state.
-// The returned bool indicated if an record was found and normalised.
-func (s *State) SizeAndDo(m *dns.Msg) bool {
-	o := s.Req.IsEdns0() // TODO(miek): speed this up
-	if o == nil {
-		return false
-	}
-	o.Hdr.Name = "."
-	o.Hdr.Rrtype = dns.TypeOPT
-	o.SetVersion(0)
-	if mo := m.IsEdns0(); mo != nil {
-		mo.Hdr.Name = "."
-		mo.Hdr.Rrtype = dns.TypeOPT
-		mo.SetVersion(0)
-		mo.SetUDPSize(o.UDPSize())
-		if o.Do() {
-			mo.SetDo()
-		}
-		return true
-	}
-	m.Extra = append(m.Extra, o)
-	return true
-}
-
-// Result is the result of Scrub.
-type Result int
-
-const (
-	// ScrubIgnored is returned when Scrub did nothing to the message.
-	ScrubIgnored Result = iota
-	// ScrubDone is returned when the reply has been scrubbed.
-	ScrubDone
-)
-
-// Scrub scrubs the reply message so that it will fit the client's buffer. If even after dropping
-// the additional section, it still does not fit the TC bit will be set on the message. Note,
-// the TC bit will be set regardless of protocol, even TCP message will get the bit, the client
-// should then retry with pigeons.
-// TODO(referral).
-func (s *State) Scrub(reply *dns.Msg) (*dns.Msg, Result) {
-	size := s.Size()
-	l := reply.Len()
-	if size >= l {
-		return reply, ScrubIgnored
-	}
-	// TODO(miek): check for delegation
-
-	// If not delegation, drop additional section.
-	reply.Extra = nil
-	s.SizeAndDo(reply)
-	l = reply.Len()
-	if size >= l {
-		return reply, ScrubDone
-	}
-	// Still?!! does not fit.
-	reply.Truncated = true
-	return reply, ScrubDone
-}
-
-// Type returns the type of the question as a string.
-func (s *State) Type() string { return dns.Type(s.Req.Question[0].Qtype).String() }
-
-// QType returns the type of the question as an uint16.
-func (s *State) QType() uint16 { return s.Req.Question[0].Qtype }
-
-// Name returns the name of the question in the request. Note
-// this name will always have a closing dot and will be lower cased. After a call Name
-// the value will be cached. To clear this caching call Clear.
-func (s *State) Name() string {
-	if s.name != "" {
-		return s.name
-	}
-	s.name = strings.ToLower(dns.Name(s.Req.Question[0].Name).String())
-	return s.name
-}
-
-// QName returns the name of the question in the request.
-func (s *State) QName() string { return dns.Name(s.Req.Question[0].Name).String() }
-
-// Class returns the class of the question in the request.
-func (s *State) Class() string { return dns.Class(s.Req.Question[0].Qclass).String() }
-
-// QClass returns the class of the question in the request.
-func (s *State) QClass() uint16 { return s.Req.Question[0].Qclass }
-
-// ErrorMessage returns an error message suitable for sending
-// back to the client.
-func (s *State) ErrorMessage(rcode int) *dns.Msg {
-	m := new(dns.Msg)
-	m.SetRcode(s.Req, rcode)
-	return m
-}
-
-// Clear clears all caching from State s.
-func (s *State) Clear() {
-	s.name = ""
-}
-
-const (
-	// TODO(miek): make this less awkward.
-	doTrue  = 1
-	doFalse = 2
-)