Port ECD encryption/decryption from ReFrontier (C#) and FrontierTextHandler
(Python) into common/decryption. The cipher uses a 32-bit LCG key stream with
an 8-round Feistel-like nibble transformation and CFB chaining; all six key
sets are supported, key 4 being the default for all MHF files.
On startup, loadRengokuBinary now decrypts (ECD) and decompresses (JKR) the
binary to validate pointer bounds and entry counts, then logs a structured
summary (floor counts, spawn table counts, unique monster IDs). Failures are
non-fatal — the encrypted blob is still cached and served to clients unchanged,
preserving existing behaviour. Closes#173.
Load and validate rengoku_data.bin once during server initialization
instead of reading it from disk on every client request. The file is
static ECD-encrypted config data (~4.9 KB) that never changes at
runtime. Validation checks file size and ECD magic bytes, logging a
warning if the file is missing or invalid so misconfiguration is
caught before any client connects.
main.go always sets both Channels and Registry together, making the
Channels fallback paths dead code. This removes:
- Server.Channels field from the Server struct
- 3 if/else fallback blocks in handlers_session.go (replaced with
Registry.FindChannelForStage, SearchSessions, SearchStages)
- 1 if/else fallback block in handlers_guild_ops.go (replaced with
Registry.NotifyMailToCharID)
- 3 method fallbacks in sys_channel_server.go (WorldcastMHF,
FindSessionByCharID, DisconnectUser now delegate directly)
Updates anti-patterns.md #6 to "accepted design" — Session struct is
appropriate for this game server's handler pattern, and cross-channel
coupling is now fully routed through the ChannelRegistry interface.
The global stagesLock sync.RWMutex protected map[string]*Stage, causing
all stage operations to contend on a single lock even for unrelated
stages. Any stage creation or deletion blocked all reads server-wide.
Replace with a typed StageMap wrapper around sync.Map which provides
lock-free reads and allows concurrent writes to disjoint keys. Per-stage
sync.RWMutex remains unchanged for protecting individual stage state.
StageMap exposes Get, GetOrCreate, StoreIfAbsent, Store, Delete, and
Range methods. Updated ~50 call sites across 6 production files and
9 test files.
The quest cache fields (lock, data map, expiry map) were spread across
Server with manual lock management. The old read path also missed the
RLock entirely, creating a data race. Encapsulating in a dedicated type
fixes the race and reduces Server's field count by 2.
The config package used `package _config` with a leading underscore,
which is unconventional in Go. Rename to `package config` (matching the
directory name) and use `cfg` as the standard import alias across all
93 importing files.
Resolve conflict in handlers_stage.go: keep lock-free packet
building pattern (copy session list, release lock, then build)
over upstream's in-lock QueueSendMHF approach.
Fix test compilation: remove objectIDs field references after
upstream removed it from Server struct.
Resync vendor directory with updated go.mod dependencies.
