Prevent client from controlling data to server












3














I've been making a simple socket.io program where the players can move around in an environment, with the client sending the server events.



However, it seems that the client can use the console to falsify data and send it to the server (by using socket.emit()).



Is there a way to combat that, so that the server only accepts "real" data, or to prevent the client from sending false data?










share|improve this question


















  • 4




    Only if you have some way of verifying the data. You can never trust the client.
    – SLaks
    Nov 11 at 3:06










  • If a user sends a message from the console that they could also send from the page, that would seem okay - but if there is something that would make it invalid, you could check conditions on the server? Hard to be sure without knowing more.
    – jacob.mccrumb
    Nov 11 at 4:16
















3














I've been making a simple socket.io program where the players can move around in an environment, with the client sending the server events.



However, it seems that the client can use the console to falsify data and send it to the server (by using socket.emit()).



Is there a way to combat that, so that the server only accepts "real" data, or to prevent the client from sending false data?










share|improve this question


















  • 4




    Only if you have some way of verifying the data. You can never trust the client.
    – SLaks
    Nov 11 at 3:06










  • If a user sends a message from the console that they could also send from the page, that would seem okay - but if there is something that would make it invalid, you could check conditions on the server? Hard to be sure without knowing more.
    – jacob.mccrumb
    Nov 11 at 4:16














3












3








3







I've been making a simple socket.io program where the players can move around in an environment, with the client sending the server events.



However, it seems that the client can use the console to falsify data and send it to the server (by using socket.emit()).



Is there a way to combat that, so that the server only accepts "real" data, or to prevent the client from sending false data?










share|improve this question













I've been making a simple socket.io program where the players can move around in an environment, with the client sending the server events.



However, it seems that the client can use the console to falsify data and send it to the server (by using socket.emit()).



Is there a way to combat that, so that the server only accepts "real" data, or to prevent the client from sending false data?







javascript node.js socket.io






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked Nov 11 at 3:03









Sarah

123




123








  • 4




    Only if you have some way of verifying the data. You can never trust the client.
    – SLaks
    Nov 11 at 3:06










  • If a user sends a message from the console that they could also send from the page, that would seem okay - but if there is something that would make it invalid, you could check conditions on the server? Hard to be sure without knowing more.
    – jacob.mccrumb
    Nov 11 at 4:16














  • 4




    Only if you have some way of verifying the data. You can never trust the client.
    – SLaks
    Nov 11 at 3:06










  • If a user sends a message from the console that they could also send from the page, that would seem okay - but if there is something that would make it invalid, you could check conditions on the server? Hard to be sure without knowing more.
    – jacob.mccrumb
    Nov 11 at 4:16








4




4




Only if you have some way of verifying the data. You can never trust the client.
– SLaks
Nov 11 at 3:06




Only if you have some way of verifying the data. You can never trust the client.
– SLaks
Nov 11 at 3:06












If a user sends a message from the console that they could also send from the page, that would seem okay - but if there is something that would make it invalid, you could check conditions on the server? Hard to be sure without knowing more.
– jacob.mccrumb
Nov 11 at 4:16




If a user sends a message from the console that they could also send from the page, that would seem okay - but if there is something that would make it invalid, you could check conditions on the server? Hard to be sure without knowing more.
– jacob.mccrumb
Nov 11 at 4:16












1 Answer
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Your server should always hold the state of the application, and have a list of all possible actions for each state.



For example, if your character can move on a map, the server should always keep the coordinate of the player. Let's say the player is at coordinate (x, y). The server will only allow messages that move the player to (x+1, y+1), (x-1, y+1), (x+1, y-1) or (x-1, y-1). Any other message should be discarded.



If it receives a message saying the player wants to move to (x+500, y+500), it should ignore it and potentially mark the player as a cheater and disconnect it.






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    Your server should always hold the state of the application, and have a list of all possible actions for each state.



    For example, if your character can move on a map, the server should always keep the coordinate of the player. Let's say the player is at coordinate (x, y). The server will only allow messages that move the player to (x+1, y+1), (x-1, y+1), (x+1, y-1) or (x-1, y-1). Any other message should be discarded.



    If it receives a message saying the player wants to move to (x+500, y+500), it should ignore it and potentially mark the player as a cheater and disconnect it.






    share|improve this answer




























      1














      Your server should always hold the state of the application, and have a list of all possible actions for each state.



      For example, if your character can move on a map, the server should always keep the coordinate of the player. Let's say the player is at coordinate (x, y). The server will only allow messages that move the player to (x+1, y+1), (x-1, y+1), (x+1, y-1) or (x-1, y-1). Any other message should be discarded.



      If it receives a message saying the player wants to move to (x+500, y+500), it should ignore it and potentially mark the player as a cheater and disconnect it.






      share|improve this answer


























        1












        1








        1






        Your server should always hold the state of the application, and have a list of all possible actions for each state.



        For example, if your character can move on a map, the server should always keep the coordinate of the player. Let's say the player is at coordinate (x, y). The server will only allow messages that move the player to (x+1, y+1), (x-1, y+1), (x+1, y-1) or (x-1, y-1). Any other message should be discarded.



        If it receives a message saying the player wants to move to (x+500, y+500), it should ignore it and potentially mark the player as a cheater and disconnect it.






        share|improve this answer














        Your server should always hold the state of the application, and have a list of all possible actions for each state.



        For example, if your character can move on a map, the server should always keep the coordinate of the player. Let's say the player is at coordinate (x, y). The server will only allow messages that move the player to (x+1, y+1), (x-1, y+1), (x+1, y-1) or (x-1, y-1). Any other message should be discarded.



        If it receives a message saying the player wants to move to (x+500, y+500), it should ignore it and potentially mark the player as a cheater and disconnect it.







        share|improve this answer














        share|improve this answer



        share|improve this answer








        edited Nov 11 at 20:35

























        answered Nov 11 at 20:22









        mihai

        23.3k73968




        23.3k73968






























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