Reshapes IP banning around one idea: **core owns the question, content owns every answer.**
Core gains a single accept-path seam — `IConnectionFilter` — and loses everything that used to implement one. The firewall moves to UOContent, a new file-backed blocklist joins it there, and CrowdSec is repositioned from an in-app enforcer to a contribute-first reporter.
## The seam
```csharp
public interface IConnectionFilter
{
string Name { get; }
void Configure();
void Start(CancellationToken token);
void Stop();
bool ShouldDeny(IPAddress address);
}
```
The accept path went from hardcoded branches to one question:
```csharp
else if (ConnectionFilters.ShouldDeny(remoteIP, out var deniedBy))
{
logger.Debug("{Address} denied by connection filter '{Filter}'", remoteIP, deniedBy);
}
```
Filters register during the Configure sweep. The registry is a plain array walked by an indexed loop — no enumerator, no closure, no allocation — and the first denial short-circuits. An interface dispatch is noise next to the `accept()` syscall, so pluggability costs nothing measurable on the path that has to survive a DDoS.
Whatever a hit implies — persisting, promoting to an OS bouncer, contributing to the ban channel — is the filter's business, not the accept path's.
A filter that throws is **unregistered and the connection fails open**. A filter that faults once faults for every subsequent connection, so leaving it registered means an exception and a log line per accept — exactly the amplification an attacker wants — and a broken filter must not be able to deny everyone either.
This deliberately does **not** reuse `EventSink.InvokeSocketConnect`: that fires later and allocates a `SocketConnectEventArgs` per connection, which is what the accept path avoids for rejected traffic.
## What ships behind it
**`firewall`** (UOContent) — the existing admin-curated set. Collapsed from `Firewall` + `AdminFirewall` + a threaded enforcer into one single-threaded store with **zero concurrency primitives**: the accept path, admin gump, TTL expiry and boot load all run on the game loop. Persists to `Configuration/firewall.json` with automatic migration from the legacy `firewall.cfg`. No behavior change for operators — same namespace, same gump, same commands.
**`blocklist`** (UOContent) — new. Holds a millions-strong list in-app and **demand-pages** hits up to CrowdSec, which promotes them to the OS firewall.
The motivation is concrete: CrowdSec's Windows bouncer cannot load the ~3.9M IPs that 91 community feeds produce, but it handles ~100k fine. So the millions live in-process behind a binary search, and only addresses that *actually connect* get promoted. A `PromotedGuard` suppresses re-reporting an address until the bouncer picks it up.
The list is parsed straight from UTF-8 file bytes with no per-line string allocation, off the game loop, and published as an immutable snapshot swapped through a single `volatile` reference. Reloads yield to world saves.
**`tools/Export-IpBlocklist.ps1`** — the producer. Requires PowerShell 7 and runs on Windows, Linux and macOS; Windows PowerShell 5.1 is refused up front via `#requires`. Merges a thin, non-overlapping feed set into one de-duplicated, bogon-filtered file. Parsing runs in a compiled `Add-Type` hot loop (~1s for ~4M lines instead of minutes). Written to a `.tmp` sibling and swapped with `File.Replace`, so the shard never reads a half-written list, and a total feed outage refuses to overwrite a good list with an empty one. Re-running is idempotent — it exits without downloading anything while the list on disk is younger than `-MinInterval` (default 2h, the anchor feed's own refresh period), so a misconfigured scheduler can't hammer upstream.
## CrowdSec: contribute-first
`IBanReporter` + `BanChannel` fan locally-decided bans out to external systems. `CrowdSecReporter` (UOContent) posts to LAPI `POST /v1/alerts` and retracts via `DELETE /v1/decisions`.
Reporting is **enqueue-only** on the accept path: a bounded, coalescing channel drained off-loop with bounded retry, counted drops on overflow, and a flush on shutdown. Under a DDoS the accept path never does synchronous or lock-contending per-IP work.
### Why not pull decisions from CrowdSec?
The original design streamed decisions into an in-app snapshot and enforced them at the accept gate. That's the wrong layer: by the time the shard sees the connection, the TCP handshake and socket setup are already paid for. `cs-firewall-bouncer` drops the same traffic **at the kernel**, and it's what CrowdSec is built to do. So the shard now contributes what it uniquely knows (rate-limit trips, blocklist hits from real connection attempts) and lets the OS enforce.
The one thing the OS can't do — hold millions of entries on Windows — is exactly what the in-app blocklist covers, and it feeds the same pipeline.
## Threading policy
`CLAUDE.md` rule #3 is rewritten as an explicit three-part policy, with rule #10 restated in tandem:
- Anything touching game state runs **only** on the main loop.
- Heavy work that *needs* game state must be **chunked** across ticks, never threaded.
- Heavy work that does *not* need game state (large-file parse, external I/O) **must** run off-loop **and must yield to world saves**.
Results come back via an immutable snapshot swapped through a single `volatile` reference, or `Core.LoopContext.Post` — never by letting the scheduler decide where heavy work runs. Both new subsystems follow it.
## Shared primitives
`SortedRangeIndex<T> where T : IBinaryInteger<T>` — coalesced disjoint interval arrays plus a binary search. The firewall, the blocklist, and (as of this PR) core's reserved-network tables all use it.
Coalescing is a correctness requirement, not an optimization: multi-feed lists nest CIDRs (`/24` containing a `/32`), and a search that inspects only the rightmost run whose minimum is ≤ the value is sound **only** over disjoint runs. That bug was caught in review and is covered by regression tests.
`IPAddressUtility` collects the allocation-free `IPAddress` ↔ `UInt128` conversions and CIDR parsing that were previously scattered or duplicated.
## Config
| File | Owner | Keys |
|---|---|---|
| `Configuration/bans.json` | core | `reportRateLimitTrips`, `autoBanDuration` |
| `Configuration/blocklist.json` | content | `file`, `reloadInterval`, `reportHits`, `banDuration`, `promoteSuppression` |
| `Configuration/crowdsec.json` | content | `lapiUrl`, `machineId`, `password`, `origin`, `manualBanDuration`, `flushInterval`, `maxQueue` |
| `Configuration/firewall.json` | content | persisted firewall entries (migrated from `firewall.cfg`) |
Everything is inert by default. CrowdSec self-disables without credentials; the blocklist self-disables until its file exists. A shard that changes nothing sees no behavior change.
## Notes for review
- **Core no longer references `Firewall` or `IFirewallEntry` anywhere.** `NetworkUtilities` used to build its reserved-network tables out of `CidrFirewallEntry`, which coupled core to the firewall for something unrelated to banning; those are now a `SortedRangeIndex<UInt128>`, same semantics and public API.
- **`BanChannel.Stop()` no longer persists the firewall** — a contribution coordinator has no business saving an enforcement store. That's the firewall filter's `Stop()`.
- **A dead `whitelisted` parameter was dropped** from the blocklist gate: it was hardcoded `false` at its only call site, and no whitelist concept exists in core.
- **The blocklist filter is an instance, not a static.** The static version forced its tests onto the sequential collection with a reset hook; they now run in parallel.
- `dev-docs/networking-packets.md` documents the seam for content authors, plus a known wart in the `IPAddress` ↔ `UInt128` normalization flagged for a follow-up PR.
- The generator was verified on Linux, macOS and Windows under a temporary CI matrix (since removed). It caught two portability bugs — a Windows-only path separator, and a culture-sensitive duration parse that read `2.5` as `25` on comma-decimal locales and *silently* turned a 2.5h cooldown into 25h — plus a third that made the script unparseable on Windows PowerShell 5.1. The source is ASCII-only for that last reason: `#requires` is only honored once a file parses, so non-ASCII in a BOM-less script produces parse errors instead of the version message.
## Tests
**1344 pass** (782 `Server.Tests`, 562 `UOContent.Tests`). New coverage: filter registry (registration, short-circuit, fault-disable), blocklist parsing/CIDR/coalescing, snapshot reload markers, promote-guard TTL, ban-channel fan-out, CrowdSec alert building/dedup/flush-on-stop, and the generator's output-format contract pinned against the reader.
## Summary
Adds two pieces of pathfinding tooling on top of PR #2448's lazy `.swb` infrastructure:
- **`PathfindRecorder`** — admin-toggled JSONL telemetry capture; one record per `BitmapAStarAlgorithm.Find` call. Output format matches the BDN harness corpus, so production traffic can be captured and replayed in benchmarks without an adapter.
- **Public bake helpers on `StepCache`** — `ComputeLiveTileDataHash`, `TryReadTileDataHashFromFile`, `BakeMap`, `ClearResidentChunks`. Lets the benchmark project (and any future bake utility) drive cache fill + persist without exposing internal types.
The companion BDN harness update lives in [ModernUO-Benchmarks#kb/pathfinding-pr4-bench](https://github.com/modernuo/ModernUO-Benchmarks/tree/kb/pathfinding-pr4-bench): porting `Benchmarks/PathfindInGame/` from the `kb/ai_pathfinding` branch to the API shipped in #2446–#2448.
## What's in this PR
### `PathfindRecorder` (`PathfindRecorder.cs`)
- Holds a single `StreamWriter` open while recording; its internal buffer absorbs per-record writes without per-call `File.AppendAllText`.
- Single `bool` check on the hot path; cheap when disabled.
- Disabling flushes + disposes; an IO failure during write also disables the recorder.
- Server config:
- `pathfinding.recorder.enable` — bool, default `false`. Read on boot via `GetOrUpdateSetting`.
- `pathfinding.recorder.path` — default `<basedir>/Data/Pathfinding/recordings/pathfinds.jsonl`.
- Hooked into `BitmapAStarAlgorithm.Find` — runs once per call, does nothing when disabled.
- Admin command: `[PathRecord [on|off|flush|status]` (default `status`).
### Public cache helpers
- `static ulong StepCache.ComputeLiveTileDataHash()` — wraps the file module's hash function for staleness checks.
- `static bool StepCache.TryReadTileDataHashFromFile(string, out ulong)` — peeks at a `.swb` file's hash field (20 bytes).
- `int StepCache.BakeMap(int, string)` — walks every chunk in the map, populates resident set, saves. Offline / fixture use; blocks for many seconds on a full-map walk.
- `void StepCache.ClearResidentChunks()` — drops chunks + zeros counters but keeps lazy readers open. Lets benchmark loops measure "first query after boot" cost across iterations without the lazy-reader reopen overhead.
## Summary
Adds a binary disk format + lazy reader so the step cache can warm-start from a precomputed file without paying chunk-build cost on the first pathfind through a region. **Resident memory stays bounded by `MaxResidentChunks` regardless of file size** — opening a `.swb` reads only the header + chunk-offset index (~16 bytes per indexed chunk), and individual chunks are seeked + deserialized only when `ResolveMissingChunk` asks for them.
The lazy design (vs. an eager bulk load): a 250 MB bake on a RAM-constrained shard never materializes more than the LRU cap (~40 MB at the default 8192-chunk cap), and unwanted regions never enter memory at all.
Builds on PR #2447.
## What changed
- **`StepCacheFile`** — binary reader/writer module. Writer emits header → chunks (offsets recorded) → index trailer, then patches the header's `IndexOffset` field. Reader is `OpenForLazy(path)` returning a `LazyReader` that holds an open `FileStream` + offset dictionary.
- **`StepCacheFile.LazyReader`** — `TryReadChunk(chunkX, chunkY)` does a single seek + bulk read for one record. `Dispose` releases the underlying stream. Files are opened with `FileShare.Read | FileShare.Delete` so admin tooling can replace them.
- **TileData fingerprint via XxHash3.** The `.swb` header carries a hash of `LandTable + ItemTable` flags. Load rejects any file whose hash doesn't match the running server. Computed via `HashUtility.ComputeHash64` (engine-blessed hasher) — adds a `ReadOnlySpan<byte>` overload alongside the existing `ReadOnlySpan<char>` one for parity.
- **`StepCache.SaveToFile(path, mapId)`** — writes resident chunks for the given map.
- **`StepCache.TryOpenLazyReader(path, mapId)`** — opens the file, validates header, holds the reader for the map's lifetime.
- **`StepCache.ResolveMissingChunk`** — now consults the lazy reader before invoking the runtime baker. A loaded chunk whose `BuiltMultisVersion` doesn't match the live sector falls through to the baker (snapshot was made before a multi was added/removed in that sector).
- **`StepCache.Clear` closes lazy readers.** Test cleanup can delete `.swb` files cleanly.
- **Auto-load at startup.** `PathCacheCommands.Configure()` opens `Data/Pathfinding/<mapId>.swb` as a lazy reader for every map.
- **`[PathCacheSave`** / **`[PathCacheLoad`** — admin commands for the same workflow.
- **`pathfinding.maxResidentChunks` shard-tunable.** Read from `server.cfg` at boot via `ServerConfiguration.GetOrUpdateSetting` (default 8192 ≈ 40 MB). Small shards can tune down; large shards with substantial bakes can tune up to reduce eviction churn. Default is written back to `server.cfg` on first boot, matching the engine pattern used by other settings.
## File layout (v1)
```
Header (48 bytes):
u32 Magic = 0x42575300 ('SWB\0')
u32 Version = 1
u32 MapId
u64 TileDataHash XxHash3 over LandTable + ItemTable flags (HashUtility)
u64 BakeTimestamp informational
u32 ChunkCount
u64 IndexOffset file position where the chunk index begins
Chunk records (fixed size, ~5,393 bytes each, +32 if multi-Z):
u16 ChunkX
u16 ChunkY
u32 BuiltMultisVersion
u8 HasMultiZ
byte WalkMask[256], WetMask[256]
sbyte SourceZ[256], WalkZN..WalkZNW[256], SwimZN..SwimZNW[256]
[byte MultiZCells[32] when HasMultiZ == 1]
Index trailer (16 × ChunkCount bytes):
(u64 chunkKey, u64 fileOffset)
```
## Memory math
| Scenario | Disk file | RAM at boot | Notes |
|---|---|---|---|
| Empty / no `.swb` files | — | 0 | Silent; cache builds on demand. |
| Admin-curated towns (5K chunks) | 25 MB | 0 + per-query | Index ≈ 80 KB. Resident grows to the configured cap under steady-state queries. |
| Full-map bake (50K chunks) | 250 MB | 0 + per-query | Index ≈ 800 KB. Same configured cap. Cold areas never load. |
| All 5 maps fully baked | 1.25 GB | 0 + per-query | Index ≈ 4 MB total. Same configured cap. |
## Hash choice (FNV-1a → XxHash3)
The original draft used inlined FNV-1a-64. Switched to XxHash3 via `HashUtility`:
- ~30× faster on this workload (~30 GB/s SIMD vs ~2 GB/s byte-by-byte). Boot-time only, so absolute saving is microseconds — the real wins are elsewhere.
- Stronger collision resistance and distribution.
- Drops ~25 lines of inlined hash code; matches the rest of the codebase's hashing pattern.
- Hash is stable as long as `HashUtility`'s `xxHash3Seed` constant doesn't change (already marked `// DO NOT CHANGE THIS NUMBER`).
## Summary
Removes per-call heap allocations from `Container`'s consume / find / group hot paths and from `BaseCreature.OnDeath`'s fame/karma tracking. The headline wins: kill the `List<List<Item>>` + `Item[][]` + `int[]` grouping bridges in `ConsumeTotal*` / `ConsumeTotalGrouped*` / `GetBestGroupAmount*`, and kill the per-call `Predicate<Item>` allocations in `FindItemsByType(Type)` / `FindItemsByType(Type[])`.
### `Container.cs`
- `ConsumeTotal`, `ConsumeTotalGrouped`, `GetBestGroupAmount` now share four streaming helpers (`HasAmount`, `TryFindGroupMeetingAmount`, `BestGroupTotal`, `ConsumeSlice`) backed by `PooledRefList` instead of allocating per-group lists and jagged arrays. Two-phase validate-then-consume pattern preserved — all-or-nothing semantics for spell reagents, vendor pay, and crafting still hold.
- `(Type)` / `(Type[])` / `(Type[][])` overload trios collapsed to single `ReadOnlySpan<Type>` + `ReadOnlySpan<int>` implementations. Implicit `T[] → ReadOnlySpan<T>` conversion means UOContent callers compile unchanged.
- Unused overloads deleted: `ConsumeTotalGrouped(Type)`, `ConsumeTotalGrouped(Type[][])`, `GetBestGroupAmount(Type)`, `GetBestGroupAmount(Type[][])`, plus the never-called `TryDropItems` hook and its private `ItemStackEntry` struct.
- Fixes a `PooledRefList` leak in `GetBestGroupAmount(Type[], …)` (missing `using`).
- `m_ContainerData` / `m_Items` / `m_TotalGold` / `m_TotalItems` / `m_TotalWeight` / `ContainerData.m_Table` / `ContainerData.logger` renamed to the underscored convention. `m_Items` cross-file rename for the Container-side references in `Item.cs`; `Item.CompactInfo.m_Items` deliberately left alone (separate effort).
- `CheckHold` parent walk simplified; trivial dispatch methods (`CheckHold` overloads, `OnItemAdded`, `OnItemRemoved`, `OnStackAttempt`) get `[MethodImpl(AggressiveInlining)]`; `Destroy` and `DisplayTo` cache `Items` outside the loop; dead comments removed.
### `Item.Enumerable.cs`
- `FindItemsByType(Type)` previously allocated a `Predicate<Item>` per call (method-group conversion). `FindItemsByType(Type[])` allocated a closure capturing `types`. Both now construct the enumerator with a `Type` / `ReadOnlySpan<Type>` field directly, no delegate.
- `FindItemsByTypeEnumerator<T>` gains two constructors plus a `Matches(T)` helper that picks the right filter inline. Constructor chaining via a private 2-arg seed constructor incidentally fixes a pre-existing bug where `PooledRefQueue` was always rented at capacity 0 because `_recurse` hadn't been assigned yet.
- `(Type[])` overload of `FindItemsByType` becomes `(ReadOnlySpan<Type>)`.
- `EnumerateItemsByType(Type)` / `EnumerateItemsByType(ReadOnlySpan<Type>)` / `ListItemsByType(Type)` / `ListItemsByType(ReadOnlySpan<Type>)` simplified to delegate to the new alloc-free overloads instead of filtering manually.
### `Utility.cs`
- `InTypeList<T>(this T, Type[])` and `InTypeList(this Type, Type[])` switched to `ReadOnlySpan<Type>`.
### `BaseCreature.cs`
- `OnDeath` per-death `List<Mobile>` / `List<int>` / `List<int>` for fame/karma tracking switched to `PooledRefList`.
> [!IMPORTANT]
> **Breaking Changes**
> - DecodePacket and EncodePacket delegates replaced with IClientEncryption interface
> - NetState.Connection (Socket) replaced with internal RingSocket management
> - NetState.RecvPipe and NetState.SendPipe removed (buffers managed internally)
## Summary
Upgrades the networking stack from PollGroup-based I/O to io_uring, significantly improving I/O performance on Linux.
This also adds native client encryption support for encrypted UO clients.
## Major Changes
io_uring Networking Architecture
- Replaced PollGroup with IORingGroup for async socket I/O operations
- Removed Pipe.cs (mirrored ring buffer) and TcpServer.cs in favor of RingSocketManager
- Added NetState.Network.cs - centralized network infrastructure handling accept, recv, send, and disconnect
completions
- Added SocketHelper.cs - platform-specific socket utilities for raw socket handle operations (getpeername,
getsockname)
- Buffer management now handled by RingSocketManager with configurable slab allocation
### Client Encryption Support
- Added full encryption stack in Network/Encryption/:
- EncryptionConfig.cs - configurable encryption modes (None, Unencrypted, Encrypted, Both)
- EncryptionManager.cs - encryption detection and initialization for login/game packets
- LoginEncryption.cs - handles login packet encryption with version-derived keys
- GameEncryption.cs - handles game server encryption using Twofish
- TwofishEngine.cs - optimized Twofish block cipher implementation
- LoginKeys.cs - encryption key table for client versions
- IClientEncryption.cs - interface for client encryption implementations
### NetState Improvements
- Replaced Socket Connection with RingSocket _socket for managed socket lifecycle
- Changed from GCHandle polling to event-based completion processing
- Disconnect handling now properly waits for pending sends to flush
- Simplified connecting socket management using lazy queue removal
### Configuration
- New settings: network.encryptionMode and network.encryptionDebug
- Encryption mode flags: Unencrypted, Encrypted, or Both
### Dependencies
- Replaced PollGroup NuGet package with IORingGroup
- Linux requires liburing-dev / liburing-devel package
### Test plan
- Verify server starts and accepts connections on Linux with io_uring
- Verify server starts and accepts connections on Windows (fallback to IOCP)
- Test unencrypted client connections (ClassicUO with encryption disabled)
- Test encrypted client connections if available
- Verify graceful disconnect flushes pending data
- Confirm CI builds pass on all target platforms
### Summary
- Create BitMask256 struct with scalar operations (benchmarks showed AVX2 vectorization provides no benefit for this size)
- Refactor Map.cs to use BitMask256 for full Z range support (-128 to 127)
- Remove SectorSpawnCache struct, use BitMask256 directly in manager
- Update tests to use BitMask256 directly
- Remove unused test assertions for old 64-bit behavior
> [!IMPORTANT]
> **Developer Note**
> THIS IS A BREAKING CHANGE TO THE NEW API GUMP.
> Please give us feedback in [discord ](https://muo.gg/discord) if you have issues, need help, or have ideas for a better API change!
### Summary
* Adds support for size/style to dynamic/static builder.
* Drastically simplifies the dynamic/static builder api for AddHtml.
* Cleans up some legacy gump files.
New Jail System for MUO
----------------------------
Commands:
[jail [player] [reason] - Jail with time escalation per offense (5 to 120 minutes, GM only)
[unjail [player] - Manual release from jail regardless of time (GM only)
[jailinfo [player] - Check jail status and history (GM only)
[jailrecord - Checks their own jail record stats (player access)
Jail/Unjail can be found in the client view of a player in Admin Gump
Jail record gump, invoked with [jailrecord (30 second cooldown)
### Summary
Refactors ScheduledEvent and EventScheduler API to use TimeOnly so recurrence offset is explicit.
API:
```cs
public ScheduledEvent(
DateTime startAfter,
DateTime endOn,
TimeOnly time,
IRecurrencePattern recurrence,
TimeZoneInfo timeZone = null
)
```
Example:
```cs
// Schedule a daily event at 8:00 AM UTC
EventScheduler.DailyAt(
new DateTime(2024, 6, 1, 8, 0, 0, DateTimeKind.Utc),
() => Console.WriteLine("Daily event triggered!")
);
// Schedule a custom recurring event at 3:30 PM UTC every Monday
var recurrence = new WeeklyRecurrencePattern(1, DaysOfWeek.Monday);
EventScheduler.Shared.ScheduleEvent(
DateTime.UtcNow,
new TimeOnly(15, 30),
() => Console.WriteLine("Weekly Monday event!"),
recurrence
);
```
### Summary
* Adds an event scheduler.
* Adds conveniences for hourly, daily, weekly, biweekly, monthly, ordinal monthly, and yearly recurrences
Example:
```cs
var tz = TimeZoneInfo.FindSystemTimeZoneById("America/New_York");
// Specify the time of the day, and the day of the week you want it to occur. Make sure it is translated into Utc.
// The next occurrence will be _after_ the specified date/time.
var scheduledEvent = EventScheduler.WeeklyAt(new DateTime(2025, 04, 26, 17, 00, 00), StartEvent, tz);
void StartEvent()
{
World.Broadcast(0x30, false, "The event has started!");
}
Console.WriteLine("Event starts on {0}", scheduledEvent.NextOccurrence);
```
In this example, on _Saturday, May 3rd, 2025 @ 5pm ET_, the message "The event has started!" will be broadcasted.
### Summary
* Bumps to .NET 9 with updated dependencies
* Comparing a value type against null is no longer allowed
* CI/CD now uses the version specified in global.json
* Serialization generator updated to .NET 9 with bug fixes, fixes to turkish language, and parallelization
- Fixes double return issue with object property list that is causing corruption.
- Adds DEBUG_ARRAYPOOL define constant which will crash on double return or invalid return scenarios.
> [!IMPORTANT]
> **Developer Notes**
> STArrayPool rented arrays **MUST NOT** be returned **ONLY ONCE** otherwise there will be corruption from double-use.
> Use `DEBUG_ARRAYPOOL` to test potential broken STArrayPool use cases.
> [!NOTE]
> **Why can't I enable the debug all the time?**
> Other than the fact that it will crash due to bad code, the actual tracking system is highly detrimental/problematic for performance and memory consumption by creating objects that have a stack trace.
### Summary
- Fixed a bug caused by a bad assumption. If `m_List[index]` is sparse and null values are casted, the server does not crash.
- Fixed a bug where `PooledRefList.ToList` extension method returned the wrong list size.
### Summary
- Removes copying private setters
- Fixes duping containers
- Adds public `Dupe.DoDupe` functions for external scripts to hook into the existing logic.
### Summary
- Fixes an issue that causes CUO to crash due to bad string caching in static gumps
- Fixes wrong/bad 16bit html gump hues.
- Moves `C16232` (16-bit to 32-bit) and `C32216` (32-bit to 16-bit) to Utility class for broader use.
TODO:
- Some gumps have different 32bit (for string content) vs 16bit (for localized content) strings. Does this matter?
### Summary
- Fixes `[AdvancedSearch` being accessible by players 😱
- Adds `[GenCommands` to generate the same commands html page on https://muo.gg/commands.
- Fixes `[helpinfo` so all commands properly show up!
> [!WARNING]
> ### Developer Warning:
> Commands must now be registered in the `Configure` bootup phase.
> If a command is not registered early enough, it may not be available to systems like [helpinfo
> that cache their information.
> [!NOTE]
> ### Developer Note:
> Various commands related to generating content have been changed to _Developer_ and above access level.
### Screenshots
<img width="673" alt="image" src="https://github.com/modernuo/ModernUO/assets/3953314/b105b5c9-5eb4-4ace-93ff-1bfb31e7132f">
<img width="547" alt="image" src="https://github.com/modernuo/ModernUO/assets/3953314/e97487e8-47a5-4aa7-89cc-9fe3deda584d">
## Breaking Changes
* The Firewall and IP Limiter have been rewritten. Please read the notes carefully!
* `TcpServer.Instances` moved back to `NetState.Instances` - sorry - it was stupid to move it to begin with.
> [!Note]
> Sockets that fail the IP Limiter or Firewall will be immediately and forcibly disconnected.
> This means they will be stuck at "Verifying account..." if it was a real client.
### Summary
- Removes firewall wildcard support.
- Removes `AccessRestrictions`.
- Moves Firewall/IPLimiter to the core.
- Moves `TcpServer` to its own thread.
- Removes the `SocketConnect` and `SocketDisconnect` event sinks.
- Moves `Instances` back to `NetState.Instances`.
- Fixes a long standing bug with bad handling of duplicate listener addresses.
#### Firewall
The firewall has been completely rewritten. There is now an "Admin Firewall" which saves to the config file. Secondarily, there is an internal firewall used exclusively by the TcpServer while processing sockets. The Admin firewall mirrors it's additions/deletions to the internal firewall by adding requests to a queue.
> [!IMPORTANT]
> **Wildcard firewall entries, such as `X`, `*`, `?` are not allowed.**
> **Ranges in between IP classes or sextets are not allowed.**
> **Please make sure to use one of the following:**
> * IP Address - `192.168.1.1`
> * CIDR - `192.168.1.0/24`
> * Range - `192.168.1.1-192.168.1.100`
#### IP Limiter
The IP Limiter has been completely rewritten. The available configurations are:
```json
"ipLimiter.enable": "True",
"ipLimiter.maxConnectionsPerIP": 10,
"ipLimiter.clearConnectionAttemptsDuration": "00:00:00:10",
"ipLimiter.clearThrottledDuration": "00:00:02:00",
```
The IP Limiter is set up to prevent spamming connections from the same IP. Every time an IP connects, it is added to a connection list. After 10 attempts, the IP is added to the throttle list. To keep the system fast, the connection list is entirely wiped every 10 seconds, and the throttle list is entirely wiped every 2 minutes.
### Summary
- Works around a sneaky edge case bug in the JIT with stackalloc where sometimes the buffer is not zero'd.
- Fixes SendDisplayBoatHS
- Fixes sending health bars in the `SendEverything()` logic.
- Fixes a bug in sizing for some string helper functions.
### Developer Note
We are enabled `SkipLocalsInit` - do not rely on `stackalloc` to be zero'd. To zero the buffer, use `span.Clear();`
Closes#1606
### Summary
.NET 8 supports Xoroshiro 256** off the shelf and added Shuffle. Switching to that implementation.
### Developer Notes
* Removed many convenience methods that weren't used.
## BREAKING CHANGE
- Deletes `map.GetObjectsInRange` and `map.GetObejctsInBounds`
### Notes
Developers are expected to enumerate mobiles and items separately now using `map.GetMobilesInRange` and `map.GetItemsInRange`. This helps keep the code streamlined so we don't have to maintain multiple copies of ref struct enumerators that do the same thing.
### Fixes
- [X] Fixes bug with planks closing
- [X] Fixes issue with iterating items/mobiles from a null map
## Breaking Changes
Incoming packet registration signature has changed to:
```cs
delegate* void OnReceiveCallback(NetState state, SpanReader reader, int packetLength);
IncomingPackets.Register(int packetID, int length, bool ingame, OnReceiveCallback onReceive);
```
For example, an incoming packet handler signature would now look like this:
```cs
public static void SomeIncomingPacket(NetState state, SpanReader reader, int packetLength)
{
// Parse the data
}
```
## Summary
Updates the network Pipe class to use a mirrored memory technique. This technique involves mapping the same physical memory to two contiguous virtual memory spaces so the byte buffer appears duplicated. This allows writing to a double-sized array to wrap around without the need for the `CircularBuffer` classes.
In practice this allows us to use `Span<byte>` as if the buffer was a regular array.
### Bug Fixes
- [X] Fixes bad fixed length string parsing
