Hash checking on the client possible?

Good day, there is a client with a launcher, whether it is possible to implement such a server is started up only with this client? Well check for the sum of the hash file or something like that.

 

Thats good idea +1

 

No, it isn't really possible.
The client user can modify the client code in any way possible, so any information from the client may be wrong to trick the server.
There are some ways to make this harder, by obscuring the client code, but that's security through obscurity and doesn't really solve the issue either.