all: replace tailcfg.DiscoKey with key.DiscoPublic.

Signed-off-by: David Anderson <danderson@tailscale.com>

tailcfg/tailcfg.go

@@ -14,7 +14,6 @@ import (
 	"strings"
 	"time"
 
-	"go4.org/mem"
 	"inet.af/netaddr"
 	"tailscale.com/types/dnstype"
 	"tailscale.com/types/key"
@@ -79,19 +78,6 @@ func (u StableNodeID) IsZero() bool {
 	return u == ""
 }
 
-// DiscoKey is the curve25519 public key for path discovery key.
-// It's never written to disk or reused between network start-ups.
-type DiscoKey [32]byte
-
-// DiscoKeyFromNodePublic returns k converted to a DiscoKey.
-//
-// Deprecated: exists only as a compatibility bridge while DiscoKey
-// gets removed from the codebase. Do not introduce new uses that
-// aren't related to #3206.
-func DiscoKeyFromDiscoPublic(k key.DiscoPublic) DiscoKey {
-	return k.Raw32()
-}
-
 // User is an IPN user.
 //
 // A user can have multiple logins associated with it (e.g. gmail and github oauth).
@@ -163,7 +149,7 @@ type Node struct {
 	Key        key.NodePublic
 	KeyExpiry  time.Time
 	Machine    key.MachinePublic
-	DiscoKey   DiscoKey
+	DiscoKey   key.DiscoPublic
 	Addresses  []netaddr.IPPrefix // IP addresses of this Node directly
 	AllowedIPs []netaddr.IPPrefix // range of IP addresses to route to this node
 	Endpoints  []string           `json:",omitempty"` // IP+port (public via STUN, and local LANs)
@@ -751,7 +737,7 @@ type MapRequest struct {
 	Compress    string // "zstd" or "" (no compression)
 	KeepAlive   bool   // whether server should send keep-alives back to us
 	NodeKey     key.NodePublic
-	DiscoKey    DiscoKey
+	DiscoKey    key.DiscoPublic
 	IncludeIPv6 bool `json:",omitempty"` // include IPv6 endpoints in returned Node Endpoints (for Version 4 clients)
 	Stream      bool // if true, multiple MapResponse objects are returned
 	Hostinfo    *Hostinfo
@@ -1138,25 +1124,6 @@ func keyMarshalText(prefix string, k [32]byte) []byte {
 	return appendKey(nil, prefix, k)
 }
 
-func (k DiscoKey) String() string { return fmt.Sprintf("discokey:%x", k[:]) }
-func (k DiscoKey) MarshalText() ([]byte, error) {
-	dk := key.DiscoPublicFromRaw32(mem.B(k[:]))
-	return dk.MarshalText()
-}
-func (k *DiscoKey) UnmarshalText(text []byte) error {
-	var dk key.DiscoPublic
-	if err := dk.UnmarshalText(text); err != nil {
-		return err
-	}
-	dk.AppendTo(k[:0])
-	return nil
-}
-func (k DiscoKey) ShortString() string      { return fmt.Sprintf("d:%x", k[:8]) }
-func (k DiscoKey) AppendTo(b []byte) []byte { return appendKey(b, "discokey:", k) }
-
-// IsZero reports whether k is the zero value.
-func (k DiscoKey) IsZero() bool { return k == DiscoKey{} }
-
 func (id ID) String() string      { return fmt.Sprintf("id:%x", int64(id)) }
 func (id UserID) String() string  { return fmt.Sprintf("userid:%x", int64(id)) }
 func (id LoginID) String() string { return fmt.Sprintf("loginid:%x", int64(id)) }

tailcfg/tailcfg_clone.go

@@ -75,7 +75,7 @@ var _NodeCloneNeedsRegeneration = Node(struct {
 	Key                     key.NodePublic
 	KeyExpiry               time.Time
 	Machine                 key.MachinePublic
-	DiscoKey                DiscoKey
+	DiscoKey                key.DiscoPublic
 	Addresses               []netaddr.IPPrefix
 	AllowedIPs              []netaddr.IPPrefix
 	Endpoints               []string

tailcfg/tailcfg_test.go

@@ -407,14 +407,6 @@ func TestNetInfoFields(t *testing.T) {
 	}
 }
 
-func TestDiscoKeyMarshal(t *testing.T) {
-	var k1, k2 DiscoKey
-	for i := range k1 {
-		k1[i] = byte(i)
-	}
-	testKey(t, "discokey:", k1, &k2)
-}
-
 type keyIn interface {
 	String() string
 	MarshalText() ([]byte, error)
@@ -542,15 +534,6 @@ func TestAppendKeyAllocs(t *testing.T) {
 	}
 }
 
-func TestDiscoKeyAppend(t *testing.T) {
-	d := DiscoKey{1: 1, 2: 2}
-	got := string(d.AppendTo([]byte("foo")))
-	want := "foodiscokey:0001020000000000000000000000000000000000000000000000000000000000"
-	if got != want {
-		t.Errorf("got %q; want %q", got, want)
-	}
-}
-
 func TestRegisterRequestNilClone(t *testing.T) {
 	var nilReq *RegisterRequest
 	got := nilReq.Clone()