Because Spigot changed to fire the teleport following an altered move
end point with TeleportCause.PLUGIN, we have to alter set back handling,
so we can ensure to keep TeleportCause.UNKNOWN for setting back players.
Instead of altering the move end point, the event is just cancelled, and
a teleport is scheduled (with a dedicated TickTask method). Uncancelled
moving events mean removing scheduled teleports.
[BLEEDING]
* Comparably simple change - more places and special cases may still be
uncovered.
[BREAKING]
* Plugins that may rely on the exact sequence of things within NCP, as
it used to be.
Random
* Change "set-back" to "set back" everywhere for simplicity, and to
obfuscate the actual code changes.
* Set backs are now going through MovingListener.onCancelledMove instead
of MovingListener.onMoveMonitorNotCancelled.
* Illegal move handling would still use event.setTo.
* Split log messages: ingame vs. console+file
* Alter flylong to contain tags.
Performance-wise, it's not optimal that flylong is the same as flyfile
at this stage. Not sure if to remove flylong in favor of using flyfile,
to indicate it means details - main objective is to get minimal details
into the violation log, even if people edit it out of the ingame chat
messages.
Players and vehicles:
Instead always use UNKNOWN, as that is what results from
PlayerMoveEvent.setTo(newTo), as we use it for setting back players.
This should break functionality that relies on TeleportCause.PLUGIN
being used, possibly more likely with vehicles.
Internally, the tick is stored with a change id, so we can reuse a
changeId, if the tick is still the same, preserving rough order, as the
changeId should at least increase with the tick.
This isn't the last word on a public API, there likely will be the
following additions.
* One more simplified method with a minimal signature for simple
(non-push) entries (worldId, x, y, z, previousState).
* Optimized methods for adding multiple entries at once. Likely for
adding multiple entries of the same type/data/shape. Plus perhaps
simplified signatures to do without changeId and tick.
(Not sure if there will be need for a method allowing for a collection
of a to be defined class combining x+y+z+previousState.)
This will evolve based on feedback from GitHub issues.
Lots of issues remain with elytra, with and without boost. Selection:
* maxheight will trigger with the rocket feature, naturally. Mendable by
increasing it via configuration
(checks.moving.creativelfly.model.elytra.vertical.maxheight). Not sure
we'll just increase the limit or alter how it's dealt with (e.g. also
for sf: lock to a max / high slope value, independently of the set-back
and world height, alter as necessary).
* All sorts of transitions, e.g. onto ground, into water.
* Loss of boost right after adding (not sure if already fixed).
* What with hover, actually?
* Is the flight duration infinite with power 127?
* Issues with ascending after descending, even without boost?
Changes contain:
* MCAccess.dealFallDamageFiresAnEvent -> true
* Always log basic data on (handled) fall damage events.
* Add a tag for the cancel reason with NoFall. Alter the default alert
message.
* Move 3.0 to Magic.
* Set the skipping flag correctly on allowFlight being set.
Fall damage is adjusted or cancelled, if the Minecraft fall distance is
greater than the distance(s) tracked by NCP (per move diffs, maximum y).
Intention is to prevent (speeding by) self damage by abusing Minecraft
dealing fall for untracked moves.
Issue: https://github.com/NoCheatPlus/Issues/issues/338
Steps done:
* Add more velocity with less preconditions.
* Handle push with the player being just above the block where a slime
block is pushed to.
* Exception for vdistrel.
* Breaking:Move verVelUsed from MovingData to PlayerMoveData.
Gameplay issues remaining:
* Still too often fall damage is dealt.
* Friction envelope gets hidden with past-ground being set too often
(vdistsb).
* Potential for more edge cases.
Missing abuse prevention:
* Reinstate invalidation of past entries (currently turned off to
progress at all, will need another iteration).
* More confined preconditions.
* More/better invalidation conditions for velocity set for bounce
effects.
* Less fall damage.
* Flag all velocity added due to slime bouncing appropriately.
* Experimental concept for splitting up velocity, likely to be altered /
removed.
* Add a flag for (faked) pvp velocity.
NOTE: Invalidation of past entries has been deactivated to progress on detecting the stupid past bouncing at all. This will need another iteration.
Lots of issues remain, but vertical push/bounce with pistons is much
improved. Still there are show stoppers (false positives remain, as well
as occasional fall damage).
Use same/similar entry points, like static/classic bounce checking in
MovingListener. SurvivalFly still keeps one exception with the
after-failure Y_POS block move check.
Also check: https://github.com/NoCheatPlus/Issues/issues/5
There are typical cases to cover:
* Extra falling height.
* Fall damage where a slime block had been.
Thus adding a specialized method for bounce (just foot position) instead
of using the full bounds would be better, preferably just check within
the MovingListener (set bounce / adjust velocity there).
Still incomplete, could contain bugs (endless loops, perhaps).
Invalidation
mechanics may need to be refined.
Not covered:
* Exemption for moves resulting from horizontal push/pull.
*
* In case of non-full bounds + variable, allow ground to be found
underneath. Can concern fences (tested on 1.11).
* There has been a probably misplaced/leftover check assuming the block
above to be passable, without checking for it (iMaxY). Since the
access.getMaxBlockY() has already been checked, this part appears to be
not of use, thus iMaxY has been removed from the signature together with
this exception.
If this causes something, please provide debug logs / circumstances :).
This is unfinished, but gives an outlook on what we may be able to do
with this.
* Double doors are not covered (upper/lower half are).
* Interaction with levers / directly with doors is not covered.
* Only doors + gates (not sure what else there is).
* More fine grained configurability is missing (+ only register
listeners if needed).
* Possibly other things.
Tracking BlockRedstone seems to be more promising than BlockPhysics, as
long as we don't have to inspect neighbour blocks to check for door like
blocks at all.
Currently the oldest available entries are used, as if the player had
the maximum allowed latency always. Later on, at least attempting to hit
a global latency estimate (+window) should be attempted.
We'll still have a (moderate) fast-forward implementation to see what
opportunistic checking can do on live servers (elevators, doors etc.).
Intention is to work towards passing stored IBlockCacheNode instances to
methods in BlockProperties, i.e. to have
isOnGroundInAnOverlyOpportunisticWay implemented.
If you need one of the old BlockProperties signatures (or a more
simplified one), just open a GitHub issue.
This is a slightly peculiar change.
* Passing node and nodeAbove is a little bit odd, despite seemingly
efficient at present.
* Later we might need a BlockCache instance that busies about past
states (currently too complicated to implement).
* Uncertain impact (could perform better, could perform worse).
* Possibly left out a couple of places.
* Might have introduced bugs (fast forward).
On the other hand there may be a lot of other types of changes, if we
ever go for a less opportunistic implementation, which can not be
estimated simply, so this may be about the best that can be done, to get
a quick step in.
Already have the signature use IBlockCacheNode for node+nodeAbove, like
it will be done with other methods like collidesBlock.
This will allow calling this with past block states, once other methods
have been adapted as well.
Within BlockProperties BlockCache and IBlockCacheNode ("read only") get
passed, removing id/data/shape from arguments. If a property is not set
in the node, it'll be fetched from the block cache, but the node is not
updated from outside the BlockCache. For subsequent calls, the node
would be updated by the block cache, if it isn't a node stored by the
BlockChangeTracker from an earlier time, and similar.
This way, opportunistic passable checking can be implemented, by
switching to cached nodes instead of id/data/shape arguments with lazy
fetching from BlockCache.
The name IBlockCacheNode seems to be appropriate, since we'll pass it
alongside with a BlockCache anyway.
Cross-world teleport to the end issue: set back hard, if the player
moves to the position they set off from the last world, which seems to
be a bug with some server types/versions at present (!?).
Some packets arrive with a null world for a player, possibly sent by
plugins - thus attempt to use a stored world name.
This is just a hot fix attempt.
Attempt to enable workarounds for lily pads with servers that support
multiple client versions. Add to the configuration at
compatibility.blocks.overrideflags:
WATER_LILY: default+ign_passable+ground_height+height8_1
HEIGHT8_1 just means 1/8 height (0.125).
The ALLOW_LOWJUMP flag was intended to be used in case of
ground_height+height100 or the like leading to issues with
sprint-jumping due to the low jump detection, however other special
casing checks for bunny hopping let this still fail (less than before,
but still), thus this flag might get removed. Keeping it for now, to
provide some kind of toolkit.
Technically, tracking actual speed / base speed seems promising, done
here via using the liftOffEnvelope that is maintained anyway, adding a
counter and sum value. [Base speed is something like the allowed speed,
without accounting for specialties like bunny hopping.]
Limits are checked for moving in ground+air or water+air and are
currently hard-coded. This simplistic first-step-in may easily yield all
sorts of false positives and other random issues, handle with care.
Can't judge side effects, concerning other passable like tests telling
the head to be inside a block by the micro margin, while passable allows
such a move now.
Not sure if this really pays, if most people use protocol-support
plugins that limit packets anyway. There could be some future use, e.g.
generic rate limiting with configurable implementation.
Other:
* New methods for RawConfigFile+ConfigManager to check for
AlmostBooleanS.
* Add all net check permissions to plugin.yml.
* ICollideBlocks matches the interface better. If we ever need ICollide
for something common (e.g. set(ICollisionSetup) allows to fetch
information about start conditions and run generic tests !? not really
sure if such will happen...)
* Add ICollideRayVsAABB, to prepare other types of direction/visible
checking (enable more precision, but also configurable leniency).
This time the focus is on the utilities package.
Possibly used, but not really official API:
* Move block cache to a 'map' sub-package.
* Move RichBounds/RichEntity/Player-Location and TrigUtil to a location
sub-package.
Not really official API, likely not used:
* Move AttribUtil to compat, since it belongs there.
* Split off direction check methods to collision.CollisionUtil.
* Move static BlockCache methods to map.MapUtil.
* Move food related methods from CheckUtils to InventoryUtil.
* Move vehicle/passenger related methods from CheckUtils to
PassengerUtil.
Not breaking:
* Move IdUtil to commons.
registry.feature is rather meant for stuff that registers automatically
with adding as a component to the NoCheatPlus API.
Package organization isn't done in a very consistent way, this is just
taking a step into looking at how it would/could look like.
Likely that kind of separation can't be kept, so things will in the end
be organized by their main topic perhaps, and a registry implementation
will have to state what will be registered in what way, and possibly
have a method to allow checking what's possible to register.
Main objective is to get rid of too complex setMCAccess methods and to
be able to store handles rather permanently instead.
* Remove MCAccessHolder.
* Add/refine interfaces and implementations.
* Change constructors.
The idea is to change internals towards having a 'default'
DisableListener executing onDisable before the data removal of checks
and DataManager have been called, thus plugins or even checks might
still access all sorts data with disabling the plugin.
* Only load chunks, if there is no illegal coordinates.
* If there is no valid set-back on receiving illegal coordinates,
attempt to recover from past move / current (bug), or kick.
* Add a way to stay updated about the latest registration state for a
class.
* Add a class for the registry.
* Let the registry log all registrations.
* Make super interfaces for LogManager (simple logging of
String/Throwable).
Missing:
* More streams (REGISTRY, PLAYER/CHECK_STATUS/EVENTS or just CHECKS at
least). Make status rather the plugin status. Registry could have an
extra file.
* More efficient IGenericInstanceHandle use (wrap + reference counting).
Attempt to treat fake players less Concept is subject to change, might
want fall-back methods or skipping native access in general where it's
not needed (thus not need to check for native entities).
Other
* Don't insert dataMan into disableListeners twice.
This is neither complete nor final. Intentions are to group interfaces
better, rather organizing packages in a flat way.
At some point there will be other major move-arounds, but that'll
hopefully be a point where we have a better idea of where to put what
(...). For now the approach is to move interfaces/things rather where
it's not interfering with profane exemption API use, preferably neither
taking down the top level API layer
(NoCheatPlusAPI).
Added deprecated interfaces to prevent cncp to break too quickly.
Outlook:
* Classes that are rather only expected to be used internally for setup
will likely get moved around freely.
* Classes that have been added since last release might also get moved
around freely.
