tka: implement API surface for generating updates
Based on the builder pattern. Signed-off-by: Tom DNetto <tom@tailscale.com>
This commit is contained in:
Tom DNetto
Tom
parent
acc3b7f259
commit
5e61d52f91
|
|
@ -0,0 +1,111 @@
|
|||
// Copyright (c) 2022 Tailscale Inc & AUTHORS All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package tka
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
)
|
||||
|
||||
// UpdateBuilder implements a builder for changes to the tailnet
|
||||
// key authority.
|
||||
//
|
||||
// Finalize must be called to compute the update messages, which
|
||||
// must then be applied to all Authority objects using Inform().
|
||||
type UpdateBuilder struct {
|
||||
a *Authority
|
||||
signer func(*AUM) error
|
||||
|
||||
state State
|
||||
parent AUMHash
|
||||
|
||||
out []AUM
|
||||
}
|
||||
|
||||
func (b *UpdateBuilder) mkUpdate(update AUM) error {
|
||||
prevHash := make([]byte, len(b.parent))
|
||||
copy(prevHash, b.parent[:])
|
||||
update.PrevAUMHash = prevHash
|
||||
|
||||
if b.signer != nil {
|
||||
if err := b.signer(&update); err != nil {
|
||||
return fmt.Errorf("signing failed: %v", err)
|
||||
}
|
||||
}
|
||||
if err := update.StaticValidate(); err != nil {
|
||||
return fmt.Errorf("generated update was invalid: %v", err)
|
||||
}
|
||||
state, err := b.state.applyVerifiedAUM(update)
|
||||
if err != nil {
|
||||
return fmt.Errorf("update cannot be applied: %v", err)
|
||||
}
|
||||
|
||||
b.state = state
|
||||
b.parent = update.Hash()
|
||||
b.out = append(b.out, update)
|
||||
return nil
|
||||
}
|
||||
|
||||
// AddKey adds a new key to the authority.
|
||||
func (b *UpdateBuilder) AddKey(key Key) error {
|
||||
if _, err := b.state.GetKey(key.ID()); err == nil {
|
||||
return fmt.Errorf("cannot add key %v: already exists", key)
|
||||
}
|
||||
return b.mkUpdate(AUM{MessageKind: AUMAddKey, Key: &key})
|
||||
}
|
||||
|
||||
// RemoveKey removes a key from the authority.
|
||||
func (b *UpdateBuilder) RemoveKey(keyID KeyID) error {
|
||||
if _, err := b.state.GetKey(keyID); err != nil {
|
||||
return fmt.Errorf("failed reading key %x: %v", keyID, err)
|
||||
}
|
||||
return b.mkUpdate(AUM{MessageKind: AUMRemoveKey, KeyID: keyID})
|
||||
}
|
||||
|
||||
// SetKeyVote updates the number of votes of an existing key.
|
||||
func (b *UpdateBuilder) SetKeyVote(keyID KeyID, votes uint) error {
|
||||
if _, err := b.state.GetKey(keyID); err != nil {
|
||||
return fmt.Errorf("failed reading key %x: %v", keyID, err)
|
||||
}
|
||||
return b.mkUpdate(AUM{MessageKind: AUMUpdateKey, Votes: &votes, KeyID: keyID})
|
||||
}
|
||||
|
||||
// SetKeyMeta updates key-value metadata stored against an existing key.
|
||||
//
|
||||
// TODO(tom): Provide an API to update specific values rather than the whole
|
||||
// map.
|
||||
func (b *UpdateBuilder) SetKeyMeta(keyID KeyID, meta map[string]string) error {
|
||||
if _, err := b.state.GetKey(keyID); err != nil {
|
||||
return fmt.Errorf("failed reading key %x: %v", keyID, err)
|
||||
}
|
||||
return b.mkUpdate(AUM{MessageKind: AUMUpdateKey, Meta: meta, KeyID: keyID})
|
||||
}
|
||||
|
||||
// Finalize returns the set of update message to actuate the update.
|
||||
func (b *UpdateBuilder) Finalize() ([]AUM, error) {
|
||||
if len(b.out) > 0 {
|
||||
if parent, _ := b.out[0].Parent(); parent != b.a.Head() {
|
||||
return nil, fmt.Errorf("updates no longer apply to head: based on %x but head is %x", parent, b.a.Head())
|
||||
}
|
||||
}
|
||||
return b.out, nil
|
||||
}
|
||||
|
||||
// NewUpdater returns a builder you can use to make changes to
|
||||
// the tailnet key authority.
|
||||
//
|
||||
// The provided signer function, if non-nil, is called with each update
|
||||
// to compute and apply signatures.
|
||||
//
|
||||
// Updates are specified by calling methods on the returned UpdatedBuilder.
|
||||
// Call Finalize() when you are done to obtain the specific update messages
|
||||
// which actuate the changes.
|
||||
func (a *Authority) NewUpdater(signer func(*AUM) error) *UpdateBuilder {
|
||||
return &UpdateBuilder{
|
||||
a: a,
|
||||
signer: signer,
|
||||
parent: a.Head(),
|
||||
state: a.state,
|
||||
}
|
||||
}
|
||||
|
|
@ -0,0 +1,210 @@
|
|||
// Copyright (c) 2022 Tailscale Inc & AUTHORS All rights reserved.
|
||||
// Use of this source code is governed by a BSD-style
|
||||
// license that can be found in the LICENSE file.
|
||||
|
||||
package tka
|
||||
|
||||
import (
|
||||
"testing"
|
||||
|
||||
"github.com/google/go-cmp/cmp"
|
||||
)
|
||||
|
||||
func TestAuthorityBuilderAddKey(t *testing.T) {
|
||||
pub, priv := testingKey25519(t, 1)
|
||||
key := Key{Kind: Key25519, Public: pub, Votes: 2}
|
||||
|
||||
a, _, err := Create(&Mem{}, State{
|
||||
Keys: []Key{key},
|
||||
DisablementSecrets: [][]byte{disablementKDF([]byte{1, 2, 3})},
|
||||
}, priv)
|
||||
if err != nil {
|
||||
t.Fatalf("Create() failed: %v", err)
|
||||
}
|
||||
|
||||
pub2, _ := testingKey25519(t, 2)
|
||||
key2 := Key{Kind: Key25519, Public: pub2, Votes: 1}
|
||||
|
||||
b := a.NewUpdater(func(update *AUM) error {
|
||||
update.sign25519(priv)
|
||||
return nil
|
||||
})
|
||||
if err := b.AddKey(key2); err != nil {
|
||||
t.Fatalf("AddKey(%v) failed: %v", key2, err)
|
||||
}
|
||||
updates, err := b.Finalize()
|
||||
if err != nil {
|
||||
t.Fatalf("Finalize() failed: %v", err)
|
||||
}
|
||||
|
||||
// See if the update is valid by applying it to the authority
|
||||
// + checking if the new key is there.
|
||||
if err := a.Inform(updates); err != nil {
|
||||
t.Fatalf("could not apply generated updates: %v", err)
|
||||
}
|
||||
if _, err := a.state.GetKey(key2.ID()); err != nil {
|
||||
t.Errorf("could not read new key: %v", err)
|
||||
}
|
||||
}
|
||||
|
||||
func TestAuthorityBuilderRemoveKey(t *testing.T) {
|
||||
pub, priv := testingKey25519(t, 1)
|
||||
key := Key{Kind: Key25519, Public: pub, Votes: 2}
|
||||
pub2, _ := testingKey25519(t, 2)
|
||||
key2 := Key{Kind: Key25519, Public: pub2, Votes: 1}
|
||||
|
||||
a, _, err := Create(&Mem{}, State{
|
||||
Keys: []Key{key, key2},
|
||||
DisablementSecrets: [][]byte{disablementKDF([]byte{1, 2, 3})},
|
||||
}, priv)
|
||||
if err != nil {
|
||||
t.Fatalf("Create() failed: %v", err)
|
||||
}
|
||||
|
||||
b := a.NewUpdater(func(update *AUM) error {
|
||||
update.sign25519(priv)
|
||||
return nil
|
||||
})
|
||||
if err := b.RemoveKey(key2.ID()); err != nil {
|
||||
t.Fatalf("RemoveKey(%v) failed: %v", key2, err)
|
||||
}
|
||||
updates, err := b.Finalize()
|
||||
if err != nil {
|
||||
t.Fatalf("Finalize() failed: %v", err)
|
||||
}
|
||||
|
||||
// See if the update is valid by applying it to the authority
|
||||
// + checking if the key has been removed.
|
||||
if err := a.Inform(updates); err != nil {
|
||||
t.Fatalf("could not apply generated updates: %v", err)
|
||||
}
|
||||
if _, err := a.state.GetKey(key2.ID()); err != ErrNoSuchKey {
|
||||
t.Errorf("GetKey(key2).err = %v, want %v", err, ErrNoSuchKey)
|
||||
}
|
||||
}
|
||||
|
||||
func TestAuthorityBuilderSetKeyVote(t *testing.T) {
|
||||
pub, priv := testingKey25519(t, 1)
|
||||
key := Key{Kind: Key25519, Public: pub, Votes: 2}
|
||||
|
||||
a, _, err := Create(&Mem{}, State{
|
||||
Keys: []Key{key},
|
||||
DisablementSecrets: [][]byte{disablementKDF([]byte{1, 2, 3})},
|
||||
}, priv)
|
||||
if err != nil {
|
||||
t.Fatalf("Create() failed: %v", err)
|
||||
}
|
||||
|
||||
b := a.NewUpdater(func(update *AUM) error {
|
||||
update.sign25519(priv)
|
||||
return nil
|
||||
})
|
||||
if err := b.SetKeyVote(key.ID(), 5); err != nil {
|
||||
t.Fatalf("SetKeyVote(%v) failed: %v", key.ID(), err)
|
||||
}
|
||||
updates, err := b.Finalize()
|
||||
if err != nil {
|
||||
t.Fatalf("Finalize() failed: %v", err)
|
||||
}
|
||||
|
||||
// See if the update is valid by applying it to the authority
|
||||
// + checking if the update is there.
|
||||
if err := a.Inform(updates); err != nil {
|
||||
t.Fatalf("could not apply generated updates: %v", err)
|
||||
}
|
||||
k, err := a.state.GetKey(key.ID())
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
if got, want := k.Votes, uint(5); got != want {
|
||||
t.Errorf("key.Votes = %d, want %d", got, want)
|
||||
}
|
||||
}
|
||||
|
||||
func TestAuthorityBuilderSetKeyMeta(t *testing.T) {
|
||||
pub, priv := testingKey25519(t, 1)
|
||||
key := Key{Kind: Key25519, Public: pub, Votes: 2, Meta: map[string]string{"a": "b"}}
|
||||
|
||||
a, _, err := Create(&Mem{}, State{
|
||||
Keys: []Key{key},
|
||||
DisablementSecrets: [][]byte{disablementKDF([]byte{1, 2, 3})},
|
||||
}, priv)
|
||||
if err != nil {
|
||||
t.Fatalf("Create() failed: %v", err)
|
||||
}
|
||||
|
||||
b := a.NewUpdater(func(update *AUM) error {
|
||||
update.sign25519(priv)
|
||||
return nil
|
||||
})
|
||||
if err := b.SetKeyMeta(key.ID(), map[string]string{"b": "c"}); err != nil {
|
||||
t.Fatalf("SetKeyMeta(%v) failed: %v", key, err)
|
||||
}
|
||||
updates, err := b.Finalize()
|
||||
if err != nil {
|
||||
t.Fatalf("Finalize() failed: %v", err)
|
||||
}
|
||||
|
||||
// See if the update is valid by applying it to the authority
|
||||
// + checking if the update is there.
|
||||
if err := a.Inform(updates); err != nil {
|
||||
t.Fatalf("could not apply generated updates: %v", err)
|
||||
}
|
||||
k, err := a.state.GetKey(key.ID())
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
if diff := cmp.Diff(map[string]string{"b": "c"}, k.Meta); diff != "" {
|
||||
t.Errorf("updated meta differs (-want, +got):\n%s", diff)
|
||||
}
|
||||
}
|
||||
|
||||
func TestAuthorityBuilderMultiple(t *testing.T) {
|
||||
pub, priv := testingKey25519(t, 1)
|
||||
key := Key{Kind: Key25519, Public: pub, Votes: 2}
|
||||
|
||||
a, _, err := Create(&Mem{}, State{
|
||||
Keys: []Key{key},
|
||||
DisablementSecrets: [][]byte{disablementKDF([]byte{1, 2, 3})},
|
||||
}, priv)
|
||||
if err != nil {
|
||||
t.Fatalf("Create() failed: %v", err)
|
||||
}
|
||||
|
||||
pub2, _ := testingKey25519(t, 2)
|
||||
key2 := Key{Kind: Key25519, Public: pub2, Votes: 1}
|
||||
|
||||
b := a.NewUpdater(func(update *AUM) error {
|
||||
update.sign25519(priv)
|
||||
return nil
|
||||
})
|
||||
if err := b.AddKey(key2); err != nil {
|
||||
t.Fatalf("AddKey(%v) failed: %v", key2, err)
|
||||
}
|
||||
if err := b.SetKeyVote(key2.ID(), 42); err != nil {
|
||||
t.Fatalf("SetKeyVote(%v) failed: %v", key2, err)
|
||||
}
|
||||
if err := b.RemoveKey(key.ID()); err != nil {
|
||||
t.Fatalf("RemoveKey(%v) failed: %v", key, err)
|
||||
}
|
||||
updates, err := b.Finalize()
|
||||
if err != nil {
|
||||
t.Fatalf("Finalize() failed: %v", err)
|
||||
}
|
||||
|
||||
// See if the update is valid by applying it to the authority
|
||||
// + checking if the update is there.
|
||||
if err := a.Inform(updates); err != nil {
|
||||
t.Fatalf("could not apply generated updates: %v", err)
|
||||
}
|
||||
k, err := a.state.GetKey(key2.ID())
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
if got, want := k.Votes, uint(42); got != want {
|
||||
t.Errorf("key.Votes = %d, want %d", got, want)
|
||||
}
|
||||
if _, err := a.state.GetKey(key.ID()); err != ErrNoSuchKey {
|
||||
t.Errorf("GetKey(key).err = %v, want %v", err, ErrNoSuchKey)
|
||||
}
|
||||
}
|
||||
Loading…
Reference in New Issue