From 9afceb7ee844443cb41c2378f88871ec3c0dddce Mon Sep 17 00:00:00 2001
From: Ethan Frey <ethanfrey@users.noreply.github.com>
Date: Mon, 23 Oct 2017 18:14:28 +0200
Subject: [PATCH] ledger pubkey serializes properly, better load checks

---
 nano/keys.go      | 31 ++++++++++++++++++++++---------
 nano/keys_test.go |  6 ++++++
 2 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/nano/keys.go b/nano/keys.go
index 4bb0e97c5..a3337f1e5 100644
--- a/nano/keys.go
+++ b/nano/keys.go
@@ -12,6 +12,7 @@ import (
 	wire "github.com/tendermint/go-wire"
 )
 
+//nolint
 const (
 	NameLedgerEd25519 = "ledger"
 	TypeLedgerEd25519 = 0x10
@@ -132,16 +133,23 @@ func (pk *PrivKeyLedger) PubKey() crypto.PubKey {
 func (pk *PrivKeyLedger) getPubKey() (key crypto.PubKey, err error) {
 	// if we have no pubkey, set it
 	if pk.CachedPubKey.Empty() {
-		dev, err := getLedger()
-		if err != nil {
-			return key, errors.WithMessage(err, "Can't connect to ledger")
-		}
-		pk.CachedPubKey, _, err = signLedger(dev, []byte{0})
-		if err != nil {
-			return key, errors.WithMessage(err, "Can't sign with app")
-		}
+		pk.CachedPubKey, err = pk.forceGetPubKey()
 	}
-	return pk.CachedPubKey, nil
+	return pk.CachedPubKey, err
+}
+
+// forceGetPubKey is like getPubKey but ignores any cached key
+// and ensures we get it from the ledger itself.
+func (pk *PrivKeyLedger) forceGetPubKey() (key crypto.PubKey, err error) {
+	dev, err := getLedger()
+	if err != nil {
+		return key, errors.New("Can't connect to ledger device")
+	}
+	key, _, err = signLedger(dev, []byte{0})
+	if err != nil {
+		return key, errors.New("Please open cosmos app on the ledger")
+	}
+	return key, err
 }
 
 // Equals fulfils PrivKey Interface
@@ -229,6 +237,11 @@ func PubKeyLedgerFromBytes(key [32]byte) crypto.PubKey {
 	return PubKeyLedger{crypto.PubKeyEd25519(key)}.Wrap()
 }
 
+// Bytes fulfils pk Interface - no data, just type info
+func (pk PubKeyLedger) Bytes() []byte {
+	return wire.BinaryBytes(pk.Wrap())
+}
+
 // VerifyBytes uses the normal Ed25519 algorithm but a sha512 hash beforehand
 func (pk PubKeyLedger) VerifyBytes(msg []byte, sig crypto.Signature) bool {
 	hmsg := hashMsg(msg)
diff --git a/nano/keys_test.go b/nano/keys_test.go
index b42b091f0..40cd1b486 100644
--- a/nano/keys_test.go
+++ b/nano/keys_test.go
@@ -104,4 +104,10 @@ func TestRealLedger(t *testing.T) {
 	valid = pub.VerifyBytes(msg, sig)
 	assert.True(valid)
 
+	// make sure pubkeys serialize properly as well
+	bs = pub.Bytes()
+	bpub, err := crypto.PubKeyFromBytes(bs)
+	require.NoError(err)
+	assert.Equal(pub, bpub)
+
 }