我说的是一款没有得分上限的动作游戏，也没有办法通过重玩动作等方式来验证服务器上的分数。
我真正需要的是在Flash/PHP中最强的加密，以及一种防止人们调用PHP页面而不是通过我的Flash文件的方法。我在过去尝试了一些简单的方法，对一个分数进行多次调用，完成一个校验和/斐波那契序列等，也用Amayeta SWF加密混淆SWF，但他们最终都被黑客入侵了。
感谢StackOverflow的响应，我现在从Adobe找到了更多的信息- http://www.adobe.com/devnet/flashplayer/articles/secure_swf_apps_12.html和https://github.com/mikechambers/as3corelib -我认为我可以使用加密。但我不确定这是否能让我绕过CheatEngine。
我需要知道AS2和AS3的最佳解决方案，如果它们是不同的。
主要的问题似乎是TamperData和LiveHTTP报头，但我知道还有更高级的黑客工具，比如CheatEngine(感谢Mark Webster)
当前回答
I made kind of workaround... I had a gave where scores incremented ( you always get +1 score ). First, I started to count from random num (let's say 14 ) and when I display the scores, just showed the scores var minus 14. This was so if the crackers are looking for example for 20, they won't find it ( it will be 34 in the memory ). Second, since I know what the next point should be... I used adobe crypto library, to create the hash of what the next point should be. When I have to increment the scores, I check if the hash of the incremented scores is equal to the hash is should be. If the cracker have changed the points in the memory, the hashes are not equal. I perform some server-side verification and when I got different points from game and from the PHP, I know that cheating were involved. Here is snippet ot my code ( I'm using Adobe Crypto libraty MD5 class and random cryptography salt. callPhp() is my server side validation )
private function addPoint(event:Event = null):void{
trace("expectedHash: " + expectedHash + " || new hash: " + MD5.hash( Number(SCORES + POINT).toString() + expectedHashSalt) );
if(expectedHash == MD5.hash( Number(SCORES + POINT).toString() + expectedHashSalt)){
SCORES +=POINT;
callPhp();
expectedHash = MD5.hash( Number(SCORES + POINT).toString() + expectedHashSalt);
} else {
//trace("cheat engine usage");
}
}
使用这种技术+ SWF混淆，我能够阻止饼干。此外，当我将分数发送到服务器端时，我使用自己的小型加密/解密功能。类似这样的代码(服务器端代码不包括在内，但你可以看到算法并用PHP编写):
package {
import bassta.utils.Hash;
public class ScoresEncoder {
private static var ranChars:Array;
private static var charsTable:Hash;
public function ScoresEncoder() {
}
public static function init():void{
ranChars = String("qwertyuiopasdfghjklzxcvbnm").split("")
charsTable = new Hash({
"0": "x",
"1": "f",
"2": "q",
"3": "z",
"4": "a",
"5": "o",
"6": "n",
"7": "p",
"8": "w",
"9": "y"
});
}
public static function encodeScore(_s:Number):String{
var _fin:String = "";
var scores:String = addLeadingZeros(_s);
for(var i:uint = 0; i< scores.length; i++){
//trace( scores.charAt(i) + " - > " + charsTable[ scores.charAt(i) ] );
_fin += charsTable[ scores.charAt(i) ];
}
return _fin;
}
public static function decodeScore(_s:String):String{
var _fin:String = "";
var decoded:String = _s;
for(var i:uint = 0; i< decoded.length; i++){
//trace( decoded.charAt(i) + " - > " + charsTable.getKey( decoded.charAt(i) ) );
_fin += charsTable.getKey( decoded.charAt(i) );
}
return _fin;
}
public static function encodeScoreRand(_s:Number):String{
var _fin:String = "";
_fin += generateRandomChars(10) + encodeScore(_s) + generateRandomChars(3)
return _fin;
}
public static function decodeScoreRand(_s:String):Number{
var decodedString:String = _s;
var decoded:Number;
decodedString = decodedString.substring(10,13);
decodedString = decodeScore(decodedString);
decoded = Number(decodedString);
return decoded;
}
public static function generateRandomChars(_length:Number):String{
var newRandChars:String = "";
for(var i:uint = 0; i< _length; i++){
newRandChars+= ranChars[ Math.ceil( Math.random()*ranChars.length-1 )];
}
return newRandChars;
}
private static function addLeadingZeros(_s:Number):String{
var _fin:String;
if(_s < 10 ){
_fin = "00" + _s.toString();
}
if(_s >= 10 && _s < 99 ) {
_fin = "0" + _s.toString();
}
if(_s >= 100 ) {
_fin = _s.toString();
}
return _fin;
}
}//end
}
然后我把这个变量和其他的假变量一起发送，它就会迷失在其中…对于小型flash游戏来说，这是一项艰巨的任务，但当涉及到奖品时，有些人就会变得贪婪。如果你需要任何帮助，给我写个便条。
欢呼,图标
其他回答
I made kind of workaround... I had a gave where scores incremented ( you always get +1 score ). First, I started to count from random num (let's say 14 ) and when I display the scores, just showed the scores var minus 14. This was so if the crackers are looking for example for 20, they won't find it ( it will be 34 in the memory ). Second, since I know what the next point should be... I used adobe crypto library, to create the hash of what the next point should be. When I have to increment the scores, I check if the hash of the incremented scores is equal to the hash is should be. If the cracker have changed the points in the memory, the hashes are not equal. I perform some server-side verification and when I got different points from game and from the PHP, I know that cheating were involved. Here is snippet ot my code ( I'm using Adobe Crypto libraty MD5 class and random cryptography salt. callPhp() is my server side validation )
private function addPoint(event:Event = null):void{
trace("expectedHash: " + expectedHash + " || new hash: " + MD5.hash( Number(SCORES + POINT).toString() + expectedHashSalt) );
if(expectedHash == MD5.hash( Number(SCORES + POINT).toString() + expectedHashSalt)){
SCORES +=POINT;
callPhp();
expectedHash = MD5.hash( Number(SCORES + POINT).toString() + expectedHashSalt);
} else {
//trace("cheat engine usage");
}
}
使用这种技术+ SWF混淆，我能够阻止饼干。此外，当我将分数发送到服务器端时，我使用自己的小型加密/解密功能。类似这样的代码(服务器端代码不包括在内，但你可以看到算法并用PHP编写):
package {
import bassta.utils.Hash;
public class ScoresEncoder {
private static var ranChars:Array;
private static var charsTable:Hash;
public function ScoresEncoder() {
}
public static function init():void{
ranChars = String("qwertyuiopasdfghjklzxcvbnm").split("")
charsTable = new Hash({
"0": "x",
"1": "f",
"2": "q",
"3": "z",
"4": "a",
"5": "o",
"6": "n",
"7": "p",
"8": "w",
"9": "y"
});
}
public static function encodeScore(_s:Number):String{
var _fin:String = "";
var scores:String = addLeadingZeros(_s);
for(var i:uint = 0; i< scores.length; i++){
//trace( scores.charAt(i) + " - > " + charsTable[ scores.charAt(i) ] );
_fin += charsTable[ scores.charAt(i) ];
}
return _fin;
}
public static function decodeScore(_s:String):String{
var _fin:String = "";
var decoded:String = _s;
for(var i:uint = 0; i< decoded.length; i++){
//trace( decoded.charAt(i) + " - > " + charsTable.getKey( decoded.charAt(i) ) );
_fin += charsTable.getKey( decoded.charAt(i) );
}
return _fin;
}
public static function encodeScoreRand(_s:Number):String{
var _fin:String = "";
_fin += generateRandomChars(10) + encodeScore(_s) + generateRandomChars(3)
return _fin;
}
public static function decodeScoreRand(_s:String):Number{
var decodedString:String = _s;
var decoded:Number;
decodedString = decodedString.substring(10,13);
decodedString = decodeScore(decodedString);
decoded = Number(decodedString);
return decoded;
}
public static function generateRandomChars(_length:Number):String{
var newRandChars:String = "";
for(var i:uint = 0; i< _length; i++){
newRandChars+= ranChars[ Math.ceil( Math.random()*ranChars.length-1 )];
}
return newRandChars;
}
private static function addLeadingZeros(_s:Number):String{
var _fin:String;
if(_s < 10 ){
_fin = "00" + _s.toString();
}
if(_s >= 10 && _s < 99 ) {
_fin = "0" + _s.toString();
}
if(_s >= 100 ) {
_fin = _s.toString();
}
return _fin;
}
}//end
}
然后我把这个变量和其他的假变量一起发送，它就会迷失在其中…对于小型flash游戏来说，这是一项艰巨的任务，但当涉及到奖品时，有些人就会变得贪婪。如果你需要任何帮助，给我写个便条。
欢呼,图标
一种简单的方法是提供高分值的加密散列及其本身的分数。例如，当通过HTTP GET发布结果时: http://example.com/highscores.php?score=500&checksum=0a16df3dc0301a36a34f9065c3ff8095
当计算这个校验和时，应该使用一个共享秘密;这个秘密永远不应该通过网络传输，而应该在PHP后端和flash前端中硬编码。上面的校验和是通过将字符串“secret”前置到分数“500”前，并通过md5sum运行来创建的。
Although this system will prevent a user from posting arbitrary scores, it does not prevent a "replay attack", where a user reposts a previously calculated score and hash combination. In the example above, a score of 500 would always produce the same hash string. Some of this risk can be mitigated by incorporating more information (such as a username, timestamp, or IP address) in the string which is to be hashed. Although this will not prevent the replay of data, it will insure that a set of data is only valid for a single user at a single time.
为了防止任何重放攻击的发生，必须创建某种类型的挑战-响应系统，例如:
The flash game ("the client") performs an HTTP GET of http://example.com/highscores.php with no parameters. This page returns two values: a randomly generated salt value, and a cryptographic hash of that salt value combined with the shared secret. This salt value should be stored in a local database of pending queries, and should have a timestamp associated with it so that it can "expire" after perhaps one minute. The flash game combines the salt value with the shared secret and calculates a hash to verify that this matches the one provided by the server. This step is necessary to prevent tampering with salt values by users, as it verifies that the salt value was actually generated by the server. The flash game combines the salt value with the shared secret, high score value, and any other relevant information (nickname, ip, timestamp), and calculates a hash. It then sends this information back to the PHP backend via HTTP GET or POST, along with the salt value, high score, and other information. The server combines the information received in the same way as on the client, and calculates a hash to verify that this matches the one provided by the client. It then also verifies that the salt value is still valid as listed in the pending query list. If both these conditions are true, it writes the high score to the high score table and returns a signed "success" message to the client. It also removes the salt value from the pending query list.
请记住，如果用户可以访问共享秘密，则上述任何技术的安全性都会受到损害
作为一种替代方法，可以通过强制客户端通过HTTPS与服务器通信，并确保客户端预先配置为只信任由您单独有权访问的特定证书颁发机构签署的证书来避免这种来回。
你说的是所谓的“客户信任”问题。因为客户端(在这种现金中，运行在浏览器中的SWF)正在做它设计要做的事情。保存高分。
问题是，你想要确保“保存分数”请求来自你的flash电影，而不是任意的HTTP请求。一种可能的解决方案是在请求时(使用flasm)将服务器生成的令牌编码到SWF中，该令牌必须随请求一起保存高分。一旦服务器保存了该分数，令牌就过期了，不能再用于请求。
这样做的缺点是，用户每次加载flash电影只能提交一个高分——你不得不强迫他们刷新/重新加载SWF，然后他们才能再次播放新的分数。
我认为最简单的方法是在游戏每次注册一个分数时调用RegisterScore(score)这样的函数，然后对其进行编码、打包并将其作为字符串发送到php脚本。php脚本知道如何正确地解码它。这将停止对php脚本的任何直接调用，因为任何强制得分的尝试都会导致解压错误。
根据我的经验，这最好是一个社会工程问题，而不是一个编程问题。与其专注于让作弊变得不可能，不如专注于通过消除作弊动机来让它变得无聊。例如，如果主要动机是公开可见的高分，那么简单地延迟高分的显示时间就可以通过消除作弊者的正反馈循环来显著减少作弊。
