From 4c7af9f16d53dfb913fa491f8c54f3a41eca3637 Mon Sep 17 00:00:00 2001
From: Olaoluwa Osuntokun <laolu32@gmail.com>
Date: Fri, 16 Jun 2017 23:38:42 +0200
Subject: [PATCH] htlcswitch: eliminate HopID in favor of a [33]byte for
 compressed pub keys

---
 htlcswitch/circuit.go    |  2 +-
 htlcswitch/interfaces.go |  9 ++-------
 htlcswitch/iterator.go   | 23 ++---------------------
 3 files changed, 5 insertions(+), 29 deletions(-)

diff --git a/htlcswitch/circuit.go b/htlcswitch/circuit.go
index 978050ea..624209c4 100644
--- a/htlcswitch/circuit.go
+++ b/htlcswitch/circuit.go
@@ -14,7 +14,7 @@ import (
 // Currently, the payment hash is used to uniquely identify each circuit.
 type circuitKey [sha256.Size]byte
 
-// String represent the circuit key in string format.
+// String returns the string representation of the circuitKey.
 func (k *circuitKey) String() string {
 	return hex.EncodeToString(k[:])
 }
diff --git a/htlcswitch/interfaces.go b/htlcswitch/interfaces.go
index b32291d4..cbf36f96 100644
--- a/htlcswitch/interfaces.go
+++ b/htlcswitch/interfaces.go
@@ -1,8 +1,6 @@
 package htlcswitch
 
 import (
-	"crypto/sha256"
-
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/lnwallet"
 	"github.com/lightningnetwork/lnd/lnwire"
@@ -83,15 +81,12 @@ type Peer interface {
 	// SendMessage sends message to remote peer.
 	SendMessage(lnwire.Message) error
 
-	// ID returns the lightning network peer id.
-	ID() [sha256.Size]byte
-
 	// WipeChannel removes the passed channel from all indexes associated
 	// with the peer.
 	WipeChannel(*lnwallet.LightningChannel) error
 
-	// PubKey returns the peer public key.
-	PubKey() []byte
+	// PubKey returns the serialize public key of the source peer.
+	PubKey() [33]byte
 
 	// Disconnect disconnects with peer if we have error which we can't
 	// properly handle.
diff --git a/htlcswitch/iterator.go b/htlcswitch/iterator.go
index f35e925c..7dd780da 100644
--- a/htlcswitch/iterator.go
+++ b/htlcswitch/iterator.go
@@ -1,34 +1,21 @@
 package htlcswitch
 
 import (
-	"bytes"
-	"encoding/hex"
+	"encoding/binary"
 	"io"
 
-	"github.com/btcsuite/golangcrypto/ripemd160"
 	"github.com/go-errors/errors"
 	"github.com/lightningnetwork/lightning-onion"
-	"github.com/lightningnetwork/lnd/routing"
-	"github.com/roasbeef/btcd/btcec"
+	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/roasbeef/btcutil"
 )
 
-// HopID represents the id which is used by propagation subsystem in order to
-// identify lightning network node.
-// TODO(andrew.shvv) remove after switching to the using channel id.
-type HopID [ripemd160.Size]byte
 // NetworkHop indicates the blockchain network that is intended to be the next
 // hop for a forwarded HTLC. The existnce of this field within the
 // ForwardingInfo struct enables the ability for HTLC to cross chain-boundaries
 // at will.
 type NetworkHop uint8
 
-// NewHopID creates new instance of hop form node public key.
-func NewHopID(pubKey []byte) HopID {
-	var routeID HopID
-	copy(routeID[:], btcutil.Hash160(pubKey))
-	return routeID
-}
 const (
 	// BitcoinHop denotes that an HTLC is to be forwarded along the Bitcoin
 	// link with the specified short channel ID.
@@ -39,9 +26,6 @@ const (
 	LitecoinHop
 )
 
-// String returns string representation of hop id.
-func (h HopID) String() string {
-	return hex.EncodeToString(h[:])
 // String returns the string representation of the target NetworkHop.
 func (c NetworkHop) String() string {
 	switch c {
@@ -54,9 +38,6 @@ func (c NetworkHop) String() string {
 	}
 }
 
-// IsEqual checks does the two hop ids are equal.
-func (h HopID) IsEqual(h2 HopID) bool {
-	return bytes.Equal(h[:], h2[:])
 var (
 	// exitHop is a special "hop" which denotes that an incoming HTLC is
 	// meant to pay finally to the receiving node.