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fix: resolve nethernet connection, ban deadlock, and nil RemoteAddr crashes

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This commit is contained in:
TarnaWijaya
2026-07-12 15:30:55 +07:00
parent abe84fb542
commit b1255bae06
4 changed files with 113 additions and 32 deletions
Download Patch File Download Diff File Expand all files Collapse all files
server/player/ban.go
+48 -19
View File
@@ -21,7 +21,7 @@ type BanEntry struct {
// BanManager handles player bans.
type BanManager struct {
mu sync.Mutex
mu sync.RWMutex
bans map[string]BanEntry
path string
}
@@ -54,14 +54,15 @@ func (bm *BanManager) Load() error {
return nil
}
// Save saves the banned players to bans.json.
func (bm *BanManager) Save() error {
bm.mu.Lock()
defer bm.mu.Unlock()
// save writes bans to disk. Must be called WITHOUT holding bm.mu.
func (bm *BanManager) save() error {
bm.mu.RLock()
var list []BanEntry
for _, entry := range bm.bans {
list = append(list, entry)
}
bm.mu.RUnlock()
data, err := json.MarshalIndent(list, "", " ")
if err != nil {
return err
@@ -69,14 +70,21 @@ func (bm *BanManager) Save() error {
return os.WriteFile(bm.path, data, 0644)
}
// Save saves the banned players to bans.json.
func (bm *BanManager) Save() error {
return bm.save()
}
// Ban bans a player by name, with optional XUID, UUID, and IP.
// IP bans are intentionally NOT stored to prevent blocking all
// players on the same local network (LAN/nethernet).
func (bm *BanManager) Ban(name string, duration time.Duration, reason string, xuid string, uuidStr string, ip string) {
bm.mu.Lock()
entry := BanEntry{
Name: name,
XUID: xuid,
UUID: uuidStr,
IP: ip,
IP: "", // Do NOT store IP to prevent LAN-wide bans
BannedAt: time.Now(),
Reason: reason,
}
@@ -85,7 +93,7 @@ func (bm *BanManager) Ban(name string, duration time.Duration, reason string, xu
}
bm.bans[strings.ToLower(name)] = entry
bm.mu.Unlock()
_ = bm.Save()
_ = bm.save()
}
// Unban unbans a player by name.
@@ -98,15 +106,28 @@ func (bm *BanManager) Unban(name string) bool {
}
bm.mu.Unlock()
if exists {
_ = bm.Save()
_ = bm.save()
}
return exists
}
// IsBanned checks if a player is banned by name, XUID, UUID, or IP.
func (bm *BanManager) IsBanned(name, xuid, uuidStr, ip string) (BanEntry, bool) {
// UnbanAll removes all bans. Useful for emergency reset.
func (bm *BanManager) UnbanAll() int {
bm.mu.Lock()
defer bm.mu.Unlock()
count := len(bm.bans)
bm.bans = make(map[string]BanEntry)
bm.mu.Unlock()
if count > 0 {
_ = bm.save()
}
return count
}
// IsBanned checks if a player is banned by name, XUID, or UUID.
// IP-based checking is intentionally excluded to prevent false
// positives on local networks where all players share the same IP.
func (bm *BanManager) IsBanned(name, xuid, uuidStr, ip string) (BanEntry, bool) {
bm.mu.RLock()
now := time.Now()
var expiredKeys []string
@@ -129,18 +150,23 @@ func (bm *BanManager) IsBanned(name, xuid, uuidStr, ip string) (BanEntry, bool)
} else if uuidStr != "" && entry.UUID != "" && strings.EqualFold(entry.UUID, uuidStr) {
foundEntry = entry
found = true
} else if ip != "" && entry.IP != "" && entry.IP == ip {
foundEntry = entry
found = true
}
}
// NOTE: IP matching is intentionally removed.
// On local networks (LAN/nethernet), all players share the
// same IP address. Matching by IP would block ALL players
// from the same network when only one should be banned.
}
}
bm.mu.RUnlock()
// Clean up expired entries with a separate write lock.
if len(expiredKeys) > 0 {
bm.mu.Lock()
for _, k := range expiredKeys {
delete(bm.bans, k)
}
go func() { _ = bm.Save() }()
bm.mu.Unlock()
go func() { _ = bm.save() }()
}
return foundEntry, found
@@ -148,8 +174,7 @@ func (bm *BanManager) IsBanned(name, xuid, uuidStr, ip string) (BanEntry, bool)
// List returns all active bans.
func (bm *BanManager) List() []BanEntry {
bm.mu.Lock()
defer bm.mu.Unlock()
bm.mu.RLock()
var active []BanEntry
now := time.Now()
var expiredKeys []string
@@ -160,11 +185,15 @@ func (bm *BanManager) List() []BanEntry {
}
active = append(active, entry)
}
bm.mu.RUnlock()
if len(expiredKeys) > 0 {
bm.mu.Lock()
for _, k := range expiredKeys {
delete(bm.bans, k)
}
go func() { _ = bm.Save() }()
bm.mu.Unlock()
go func() { _ = bm.save() }()
}
return active
}
server/player/player.go
+9
View File
@@ -533,6 +533,15 @@ func (p *Player) handleCheatCommand(name string, args []string) bool {
}
return true
case "unbanall":
count := Bans.UnbanAll()
if count > 0 {
p.Message(fmt.Sprintf("Successfully unbanned all %d players.", count))
} else {
p.Message("No players were banned.")
}
return true
case "gamemode", "gm":
if len(args) < 1 {
p.Message("Usage: /gamemode <survival/creative/adventure/spectator/0/1/2/3> [player]")
server/server.go
+45 -6
View File
@@ -349,33 +349,64 @@ func (srv *Server) listen(l Listener) {
wg.Add(1)
go func() {
defer wg.Done()
defer func() {
if r := recover(); r != nil {
srv.conf.Log.Error(fmt.Sprintf("panic handling connection: %v", r))
_ = c.Close()
}
}()
name := c.IdentityData().DisplayName
xuid := c.IdentityData().XUID
uuidStr := c.IdentityData().Identity
// Safely extract IP - nethernet/local connections may
// return nil RemoteAddr or non-standard address formats.
ip := ""
if addr := c.RemoteAddr(); addr != nil {
if host, _, err := net.SplitHostPort(addr.String()); err == nil {
addrStr := addr.String()
if addrStr != "" {
if host, _, err := net.SplitHostPort(addrStr); err == nil {
ip = host
} else {
ip = addr.String()
ip = addrStr
}
}
}
srv.conf.Log.Debug("Player connecting...", "name", name, "xuid", xuid, "ip", ip)
// Check if player is banned (by name, XUID, or UUID only - not IP).
if entry, banned := player.Bans.IsBanned(name, xuid, uuidStr, ip); banned {
msg := "You are banned from this server."
if entry.Reason != "" {
msg += " Reason: " + entry.Reason
}
if !entry.ExpiresAt.IsZero() {
timeLeft := time.Until(entry.ExpiresAt).Round(time.Second)
msg = fmt.Sprintf("You are banned from this server. Remaining time: %v", timeLeft)
if timeLeft > 0 {
msg += fmt.Sprintf(" Remaining: %v", timeLeft)
}
}
srv.conf.Log.Debug("Player banned, rejecting.", "name", name)
_ = c.WritePacket(&packet.Disconnect{Message: msg})
_ = c.Close()
return
}
if srv.PlayerCount() >= 14 && !strings.EqualFold(name, "XTarnaWijaya") && !strings.EqualFold(name, "TarnaWijaya") {
// Use the configured MaxPlayerCount instead of a hardcoded value.
// Admins bypass the player limit.
if srv.PlayerCount() >= srv.MaxPlayerCount() &&
!strings.EqualFold(name, "XTarnaWijaya") &&
!strings.EqualFold(name, "TarnaWijaya") {
srv.conf.Log.Debug("Server full, rejecting.", "name", name)
_ = c.WritePacket(&packet.Disconnect{Message: "Server is full."})
_ = c.Close()
return
}
if msg, ok := srv.conf.Allower.Allow(c.RemoteAddr(), c.IdentityData(), c.ClientData()); !ok {
srv.conf.Log.Debug("Player not allowed.", "name", name, "msg", msg)
_ = c.WritePacket(&packet.Disconnect{HideDisconnectionScreen: msg == "", Message: msg})
_ = c.Close()
return
@@ -469,12 +500,20 @@ func (srv *Server) finaliseConn(ctx context.Context, conn session.Conn, l Listen
if err := conn.StartGameContext(ctx, data); err != nil {
_ = l.Disconnect(conn, "Connection timeout.")
srv.conf.Log.Debug("spawn failed: "+err.Error(), "raddr", conn.RemoteAddr())
raddr := "nethernet"
if addr := conn.RemoteAddr(); addr != nil {
raddr = addr.String()
}
srv.conf.Log.Debug("spawn failed: "+err.Error(), "raddr", raddr)
return
}
if _, ok := srv.Player(id); ok {
_ = l.Disconnect(conn, "Already logged in.")
srv.conf.Log.Debug("spawn failed: already logged in", "raddr", conn.RemoteAddr())
raddr := "nethernet"
if addr := conn.RemoteAddr(); addr != nil {
raddr = addr.String()
}
srv.conf.Log.Debug("spawn failed: already logged in", "raddr", raddr)
return
}
_ = conn.WritePacket(&packet.ItemRegistry{Items: srv.customItems})
server/session/session.go
+5 -1
View File
@@ -176,7 +176,11 @@ func (conf Config) New(conn Conn) *Session {
if conf.Log == nil {
conf.Log = slog.Default()
}
conf.Log = conf.Log.With("name", conn.IdentityData().DisplayName, "uuid", conn.IdentityData().Identity, "raddr", conn.RemoteAddr().String())
raddr := "nethernet"
if addr := conn.RemoteAddr(); addr != nil {
raddr = addr.String()
}
conf.Log = conf.Log.With("name", conn.IdentityData().DisplayName, "uuid", conn.IdentityData().Identity, "raddr", raddr)
s := &Session{}
*s = Session{