From 9f24087f9988e746ee5b602c2276641b576f7cb6 Mon Sep 17 00:00:00 2001
From: Daniel Liu <139250065@qq.com>
Date: Thu, 16 Jul 2026 20:16:20 +0800
Subject: [PATCH] fix(eth): filter BFT broadcast to xdpos2+ peers only

PeersWithoutVote, PeersWithoutTimeout and PeersWithoutSyncInfo now skip
peers whose protocol version is below xdpos2 (100). BFT messages use
opcodes 0xe0-0xe2 which are only defined in the 227-length xdpos2
protocol; sending them to eth/63 or eth/62 peers would always fail and
trigger a spurious removePeer.
---
 eth/peer.go     | 21 ++++++++++++---------
 eth/protocol.go |  8 ++++----
 2 files changed, 16 insertions(+), 13 deletions(-)

diff --git a/eth/peer.go b/eth/peer.go
index a0be36675725..4144dbdb5bb3 100644
--- a/eth/peer.go
+++ b/eth/peer.go
@@ -535,45 +535,48 @@ func (ps *peerSet) PeersWithoutTx(hash common.Hash) []*peer {
 	return list
 }
 
-// PeersWithoutVote retrieves a list of peers that do not have a given block in
-// their set of known hashes.
+// PeersWithoutVote retrieves a list of peers that do not have a given vote in
+// their set of known hashes. Only peers supporting the XDC BFT protocol
+// (version >= xdc100) are returned.
 func (ps *peerSet) PeersWithoutVote(hash common.Hash) []*peer {
 	ps.lock.RLock()
 	defer ps.lock.RUnlock()
 
 	list := make([]*peer, 0, len(ps.peers))
 	for _, p := range ps.peers {
-		if !p.knownVote.Contains(hash) {
+		if p.version >= xdc100 && !p.knownVote.Contains(hash) {
 			list = append(list, p)
 		}
 	}
 	return list
 }
 
-// PeersWithoutTimeout retrieves a list of peers that do not have a given block in
-// their set of known hashes.
+// PeersWithoutTimeout retrieves a list of peers that do not have a given timeout in
+// their set of known hashes. Only peers supporting the XDC BFT protocol
+// (version >= xdc100) are returned.
 func (ps *peerSet) PeersWithoutTimeout(hash common.Hash) []*peer {
 	ps.lock.RLock()
 	defer ps.lock.RUnlock()
 
 	list := make([]*peer, 0, len(ps.peers))
 	for _, p := range ps.peers {
-		if !p.knownTimeout.Contains(hash) {
+		if p.version >= xdc100 && !p.knownTimeout.Contains(hash) {
 			list = append(list, p)
 		}
 	}
 	return list
 }
 
-// PeersWithoutSyncInfo retrieves a list of peers that do not have a given block in
-// their set of known hashes.
+// PeersWithoutSyncInfo retrieves a list of peers that do not have a given sync
+// info in their set of known hashes. Only peers supporting the XDC BFT protocol
+// (version >= xdc100) are returned.
 func (ps *peerSet) PeersWithoutSyncInfo(hash common.Hash) []*peer {
 	ps.lock.RLock()
 	defer ps.lock.RUnlock()
 
 	list := make([]*peer, 0, len(ps.peers))
 	for _, p := range ps.peers {
-		if !p.knownSyncInfo.Contains(hash) {
+		if p.version >= xdc100 && !p.knownSyncInfo.Contains(hash) {
 			list = append(list, p)
 		}
 	}
diff --git a/eth/protocol.go b/eth/protocol.go
index ca3583647e22..2903b4a49089 100644
--- a/eth/protocol.go
+++ b/eth/protocol.go
@@ -33,17 +33,17 @@ import (
 const (
 	eth62  = 62
 	eth63  = 63
-	xdpos2 = 100
+	xdc100 = 100
 )
 
 // protocolName is the official short name of the protocol used during capability negotiation.
 var protocolName = "eth"
 
 // ProtocolVersions are the supported versions of the eth protocol (first is primary).
-var ProtocolVersions = []uint{xdpos2, eth63}
+var ProtocolVersions = []uint{xdc100, eth63}
 
 // protocolLengths are the number of implemented message corresponding to different protocol versions.
-var protocolLengths = map[uint]uint64{xdpos2: 227, eth63: 17, eth62: 8}
+var protocolLengths = map[uint]uint64{xdc100: 227, eth63: 17, eth62: 8}
 
 const protocolMaxMsgSize = 10 * 1024 * 1024 // Maximum cap on the size of a protocol message
 
@@ -66,7 +66,7 @@ const (
 	GetReceiptsMsg = 0x0f
 	ReceiptsMsg    = 0x10
 
-	// Protocol messages belonging to xdpos2/100
+	// Protocol messages belonging to xdc/100
 	VoteMsg     = 0xe0
 	TimeoutMsg  = 0xe1
 	SyncInfoMsg = 0xe2