Securing Game Data: Techniques To Prevent Cheating And Tampering

Obfuscating Game Code to Frustrate Modification

Obfuscating game code makes it more difficult for players to understand and modify the game’s inner workings to enable cheating. Techniques like identifier renaming, control flow obfuscation, data encoding, and code virtualization can transform code into a form that is functionally equivalent but much harder to reverse engineer.

For example, identifier renaming replaces meaningful variable and function names like “CheckScore” with meaningless ones like “a123”. Control flow obfuscation adds jumps and switches that make the flow of execution convoluted. Data encoding obscures data structures and formats. And code virtualization converts code into a proprietary byte code which must be interpreted by a virtual machine.

Applying combinations of these techniques produces obfuscated code that cheaters will struggle to comprehend and manipulate to their advantage. The obfuscation must also be renewed with each software update to stay a step ahead of their efforts.

Table of Contents

Encrypting Saved Game Data

Sensitive game data like player profiles, unlocked achievements, and progression status can be encrypted before writing it to storage. Then when the game needs to load the data, it gets decrypted back into a usable form.

This protects the data from being read or altered by curious users or cheat programs. Without the decryption key, the data appears as incomprehensible gibberish.

Here is some example pseudocode for encrypting game data with a simple XOR cipher before writing to a save file, and decrypting it when loading:

Encryption:

  key = random 8 byte value
  
  for each byte b in savedGameData:
     encryptedByte = b XOR key
     write encryptedByte to file
     
Decryption:

  load key
  for each encryptedByte e in loadedFileData
     decryptedByte = e XOR key
     add decryptedByte to loadedGameData

The encrypted bytes will look random and scrambled without knowledge of the key. More advanced algorithms like AES and RSA can provide stronger protection than a simple XOR cipher. The key can be stored securely in the game code or derived from a secret master key on the server side.

Adding Validation Checks

Validation checks that analyze game data and state can detect tampering or manipulation. Some methods include:

Comparing local data with server: Online games can compare values like scores, time, resources with authoritative copies on the server. Differences indicate manipulation.
Checksum fields: Critical data structures can have checksums that get recomputed and verified during load. Changes cause a mismatch.

If tampering is detected, the game can revert values, fail to load, or trigger other checksum failure responses like logging out player or deleting saves.

Monitoring Game State for Impossible or Improbable Situations

The game runtime can analyze the state for red flag conditions that indicate cheating, including:

Physics/collision violations: Character moves through walls, instantly transports long distances
Ability usage rates violated: Skills used twice as fast as normal
Impossible statistics: Health, damage, speed exceeds allowable maximums
Combo lengths/scoring outpacing skill level: Beginner executing moves experts struggle with
Timings off: Actions occuring faster than humanly possible reaction times

Detection can trigger requesting review by server, reverting anomalous values, ignoring invalid actions, or flagging account for further monitoring.

Rate-Limiting Player Actions to Prevent Exploits

Cheats often exploit game mechanics by allowing players to take certain actions like collecting rewards or deploying abilities at an accelerated pace. Rate-limiting constrains the frequency of actions to intensities feasible for ordinary human players. Attempts to exceed thresholds can trigger countermeasures.

Examples include permitting:

No more than X reward claims per Y minutes
No more than Z uses of special powers per battle
Mandating delays between rapid inputs to match human reaction capabilities

Tight rate limits hamper efficiency of unauthorized bots/scripts that operate faster than people can. The thresholds should strike a balance between usability for real players and cheat obstruction.

Permanently Banning Repeat Offenders

Players that are repeatedly detected manipulating game code or memory to cheat may need their accounts permanently closed to prevent further abuse. Bans can be based on:

Exceeding a threshold of cheating offenses across a network
Triggering fraud detection mechanisms multiple times
Frequently tampering with unauthorized programs despite warnings

Banning renders purchased licenses inactive, closes accounts, and blocks creation of new accounts. Combining multiple defensive measures with permanent consequences significantly decreases financial incentives for advancing cheating methods.

Obtaining Player Feedback to Detect Cheating Patterns

Enable players to report suspected instances of cheating, collecting details like:

Game mode cheater detected in
Player name/ID and other identifying details
Abnormal behavior witnessed
Game events preceding suspicious activity
Any other suspicious traits

Aggregate reports to find common cheating patterns, problematic game areas needing rework, and accounts requiring investigation for fraud mitigation models to learn from.
Follow-up confirmations on disciplinary actions against accounts can also increase reporting through community feedback.