control/noise: adjust implementation to match revised spec.

Signed-off-by: David Anderson <danderson@tailscale.com>
2021-07-29 11:59:40 -07:00
parent 89a68a4c22
commit 0b392dbaf7
6 changed files with 300 additions and 90 deletions
@@ -0,0 +1,26 @@
+// Copyright (c) 2020 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 noise
+
+// Note that these types are deliberately separate from the types/key
+// package. That package defines generic curve25519 keys, without
+// consideration for how those keys are used. We don't want to
+// encourage mixing machine keys, node keys, and whatever else we
+// might use curve25519 for.
+//
+// Furthermore, the implementation in types/key does some work that is
+// unnecessary for machine keys, and results in a harder to follow
+// implementation. In particular, machine keys do not need to be
+// clamped per the curve25519 spec because they're only used with the
+// X25519 operation, and the X25519 operation defines its own clamping
+// and sanity checking logic. Thus, these keys must be used only with
+// this Noise protocol implementation, and the easiest way to ensure
+// that is a different type.
+
+// PrivateKey is a Tailscale machine private key.
+type PrivateKey [32]byte
+
+// PublicKey is a Tailscale machine public key.
+type PublicKey [32]byte