edns0 cleanups (#1595)

Mostly trickered by:

~~~
-               return &EDNS0_ESU{Code: EDNS0ESU}
+               return new(EDNS0_ESU)
~~~

dont see why this 'case' needs to be different than all the others. Some
various textual changes for the test.

Signed-off-by: Miek Gieben <miek@miek.nl>

edns.go

@@ -58,16 +58,15 @@ func makeDataOpt(code uint16) EDNS0 {
  case EDNS0EDE:
  return new(EDNS0_EDE)
  case EDNS0ESU:
- return &EDNS0_ESU{Code: EDNS0ESU}
+ return new(EDNS0_ESU)
  default:
  e := new(EDNS0_LOCAL)
  e.Code = code
  return e
  }
 }
 
-// OPT is the EDNS0 RR appended to messages to convey extra (meta) information.
-// See RFC 6891.
+// OPT is the EDNS0 RR appended to messages to convey extra (meta) information. See RFC 6891.
 type OPT struct {
  Hdr RR_Header
  Option []EDNS0 `dns:"opt"`
@@ -144,8 +143,6 @@ func (*OPT) parse(c *zlexer, origin string) *ParseError {
 
 func (rr *OPT) isDuplicate(r2 RR) bool { return false }
 
-// return the old value -> delete SetVersion?
-
 // Version returns the EDNS version used. Only zero is defined.
 func (rr *OPT) Version() uint8 {
  return uint8(rr.Hdr.Ttl & 0x00FF0000 >> 16)
@@ -236,8 +233,8 @@ type EDNS0 interface {
 // e.Nsid = "AA"
 // o.Option = append(o.Option, e)
 type EDNS0_NSID struct {
- Code uint16 // Always EDNS0NSID
- Nsid string // This string needs to be hex encoded
+ Code uint16 // always EDNS0NSID
+ Nsid string // string needs to be hex encoded
 }
 
 func (e *EDNS0_NSID) pack() ([]byte, error) {
@@ -275,7 +272,7 @@ func (e *EDNS0_NSID) copy() EDNS0 { return &EDNS0_NSID{e.Code, e.Nsid}
 // When packing it will apply SourceNetmask. If you need more advanced logic,
 // patches welcome and good luck.
 type EDNS0_SUBNET struct {
- Code uint16 // Always EDNS0SUBNET
+ Code uint16 // always EDNS0SUBNET
  Family uint16 // 1 for IP, 2 for IP6
  SourceNetmask uint8
  SourceScope uint8
@@ -399,8 +396,8 @@ func (e *EDNS0_SUBNET) copy() EDNS0 {
 //
 // There is no guarantee that the Cookie string has a specific length.
 type EDNS0_COOKIE struct {
- Code uint16 // Always EDNS0COOKIE
- Cookie string // Hex-encoded cookie data
+ Code uint16 // always EDNS0COOKIE
+ Cookie string // hex encoded cookie data
 }
 
 func (e *EDNS0_COOKIE) pack() ([]byte, error) {
@@ -430,7 +427,7 @@ func (e *EDNS0_COOKIE) copy() EDNS0 { return &EDNS0_COOKIE{e.Code, e.C
 // e.Lease = 120 // in seconds
 // o.Option = append(o.Option, e)
 type EDNS0_UL struct {
- Code uint16 // Always EDNS0UL
+ Code uint16 // always EDNS0UL
  Lease uint32
  KeyLease uint32
 }
@@ -469,7 +466,7 @@ func (e *EDNS0_UL) unpack(b []byte) error {
 // EDNS0_LLQ stands for Long Lived Queries: http://tools.ietf.org/html/draft-sekar-dns-llq-01
 // Implemented for completeness, as the EDNS0 type code is assigned.
 type EDNS0_LLQ struct {
- Code uint16 // Always EDNS0LLQ
+ Code uint16 // always EDNS0LLQ
  Version uint16
  Opcode uint16
  Error uint16
@@ -515,7 +512,7 @@ func (e *EDNS0_LLQ) copy() EDNS0 {
 
 // EDNS0_DAU implements the EDNS0 "DNSSEC Algorithm Understood" option. See RFC 6975.
 type EDNS0_DAU struct {
- Code uint16 // Always EDNS0DAU
+ Code uint16 // always EDNS0DAU
  AlgCode []uint8
 }
 
@@ -539,7 +536,7 @@ func (e *EDNS0_DAU) copy() EDNS0 { return &EDNS0_DAU{e.Code, e.AlgCode} }
 
 // EDNS0_DHU implements the EDNS0 "DS Hash Understood" option. See RFC 6975.
 type EDNS0_DHU struct {
- Code uint16 // Always EDNS0DHU
+ Code uint16 // always EDNS0DHU
  AlgCode []uint8
 }
 
@@ -563,7 +560,7 @@ func (e *EDNS0_DHU) copy() EDNS0 { return &EDNS0_DHU{e.Code, e.AlgCode} }
 
 // EDNS0_N3U implements the EDNS0 "NSEC3 Hash Understood" option. See RFC 6975.
 type EDNS0_N3U struct {
- Code uint16 // Always EDNS0N3U
+ Code uint16 // always EDNS0N3U
  AlgCode []uint8
 }
 
@@ -588,7 +585,7 @@ func (e *EDNS0_N3U) copy() EDNS0 { return &EDNS0_N3U{e.Code, e.AlgCode} }
 
 // EDNS0_EXPIRE implements the EDNS0 option as described in RFC 7314.
 type EDNS0_EXPIRE struct {
- Code uint16 // Always EDNS0EXPIRE
+ Code uint16 // always EDNS0EXPIRE
  Expire uint32
  Empty bool // Empty is used to signal an empty Expire option in a backwards compatible way, it's not used on the wire.
 }
@@ -668,7 +665,7 @@ func (e *EDNS0_LOCAL) unpack(b []byte) error {
 // EDNS0_TCP_KEEPALIVE is an EDNS0 option that instructs the server to keep
 // the TCP connection alive. See RFC 7828.
 type EDNS0_TCP_KEEPALIVE struct {
- Code uint16 // Always EDNSTCPKEEPALIVE
+ Code uint16 // always EDNSTCPKEEPALIVE
 
  // Timeout is an idle timeout value for the TCP connection, specified in
  // units of 100 milliseconds, encoded in network byte order. If set to 0,
@@ -839,13 +836,12 @@ func (e *EDNS0_EDE) unpack(b []byte) error {
  return nil
 }
 
-// The EDNS0_ESU option for ENUM Source-URI Extension
+// The EDNS0_ESU option for ENUM Source-URI Extension.
 type EDNS0_ESU struct {
- Code uint16
+ Code uint16 // always EDNS0ESU
  Uri string
 }
 
-// Option implements the EDNS0 interface.
 func (e *EDNS0_ESU) Option() uint16 { return EDNS0ESU }
 func (e *EDNS0_ESU) String() string { return e.Uri }
 func (e *EDNS0_ESU) copy() EDNS0 { return &EDNS0_ESU{e.Code, e.Uri} }