From cc3c18a6a7d89ca1ced6053607a2b480d9cded21 Mon Sep 17 00:00:00 2001
From: Erik Grinaker <erik@interchain.berlin>
Date: Wed, 23 Dec 2020 13:32:30 +0100
Subject: [PATCH] p2p: add NodeID.Validate(), replaces validateID()

---
 p2p/key.go        | 30 +++++++++++++++++++++++++++++-
 p2p/netaddress.go | 21 +++------------------
 p2p/switch.go     |  4 ++--
 3 files changed, 34 insertions(+), 21 deletions(-)

diff --git a/p2p/key.go b/p2p/key.go
index d970794d4..3ebae995d 100644
--- a/p2p/key.go
+++ b/p2p/key.go
@@ -2,6 +2,8 @@ package p2p
 
 import (
 	"encoding/hex"
+	"errors"
+	"fmt"
 	"io/ioutil"
 
 	"github.com/tendermint/tendermint/crypto"
@@ -11,12 +13,38 @@ import (
 )
 
 // NodeID is a hex-encoded crypto.Address.
+// FIXME: We should either ensure this is always lowercased, or add an Equal()
+// for comparison that decodes to the binary byte slice first.
 type NodeID string
 
 // NodeIDByteLength is the length of a crypto.Address. Currently only 20.
-// TODO: support other length addresses?
+// FIXME: support other length addresses?
 const NodeIDByteLength = crypto.AddressSize
 
+// Bytes converts the node ID to it's binary byte representation.
+func (id NodeID) Bytes() ([]byte, error) {
+	bz, err := hex.DecodeString(string(id))
+	if err != nil {
+		return nil, fmt.Errorf("invalid node ID encoding: %w", err)
+	}
+	return bz, nil
+}
+
+// Validate validates the NodeID.
+func (id NodeID) Validate() error {
+	if len(id) == 0 {
+		return errors.New("no ID")
+	}
+	bz, err := id.Bytes()
+	if err != nil {
+		return err
+	}
+	if len(bz) != NodeIDByteLength {
+		return fmt.Errorf("invalid ID length - got %d, expected %d", len(bz), NodeIDByteLength)
+	}
+	return nil
+}
+
 //------------------------------------------------------------------------------
 // Persistent peer ID
 // TODO: encrypt on disk
diff --git a/p2p/netaddress.go b/p2p/netaddress.go
index 5da34507c..b7c860ec3 100644
--- a/p2p/netaddress.go
+++ b/p2p/netaddress.go
@@ -5,7 +5,6 @@
 package p2p
 
 import (
-	"encoding/hex"
 	"errors"
 	"flag"
 	"fmt"
@@ -52,7 +51,7 @@ func NewNetAddress(id NodeID, addr net.Addr) *NetAddress {
 		}
 	}
 
-	if err := validateID(id); err != nil {
+	if err := id.Validate(); err != nil {
 		panic(fmt.Sprintf("Invalid ID %v: %v (addr: %v)", id, err, addr))
 	}
 
@@ -75,7 +74,7 @@ func NewNetAddressString(addr string) (*NetAddress, error) {
 	}
 
 	// get ID
-	if err := validateID(NodeID(spl[0])); err != nil {
+	if err := NodeID(spl[0]).Validate(); err != nil {
 		return nil, ErrNetAddressInvalid{addrWithoutProtocol, err}
 	}
 	var id NodeID
@@ -262,7 +261,7 @@ func (na *NetAddress) Routable() bool {
 // For IPv4 these are either a 0 or all bits set address. For IPv6 a zero
 // address or one that matches the RFC3849 documentation address format.
 func (na *NetAddress) Valid() error {
-	if err := validateID(na.ID); err != nil {
+	if err := na.ID.Validate(); err != nil {
 		return fmt.Errorf("invalid ID: %w", err)
 	}
 
@@ -414,17 +413,3 @@ func removeProtocolIfDefined(addr string) string {
 	return addr
 
 }
-
-func validateID(id NodeID) error {
-	if len(id) == 0 {
-		return errors.New("no ID")
-	}
-	idBytes, err := hex.DecodeString(string(id))
-	if err != nil {
-		return err
-	}
-	if len(idBytes) != NodeIDByteLength {
-		return fmt.Errorf("invalid hex length - got %d, expected %d", len(idBytes), NodeIDByteLength)
-	}
-	return nil
-}
diff --git a/p2p/switch.go b/p2p/switch.go
index 54841f9c0..d4c76cd38 100644
--- a/p2p/switch.go
+++ b/p2p/switch.go
@@ -592,7 +592,7 @@ func (sw *Switch) AddPersistentPeers(addrs []string) error {
 func (sw *Switch) AddUnconditionalPeerIDs(ids []string) error {
 	sw.Logger.Info("Adding unconditional peer ids", "ids", ids)
 	for i, id := range ids {
-		err := validateID(NodeID(id))
+		err := NodeID(id).Validate()
 		if err != nil {
 			return fmt.Errorf("wrong ID #%d: %w", i, err)
 		}
@@ -604,7 +604,7 @@ func (sw *Switch) AddUnconditionalPeerIDs(ids []string) error {
 func (sw *Switch) AddPrivatePeerIDs(ids []string) error {
 	validIDs := make([]string, 0, len(ids))
 	for i, id := range ids {
-		err := validateID(NodeID(id))
+		err := NodeID(id).Validate()
 		if err != nil {
 			return fmt.Errorf("wrong ID #%d: %w", i, err)
 		}