How to Ensure Security in a Gaming Peer to Peer Network

I've been recently thinking about building a c++ poker game that would let players to play over sockets in a peer to peer network. However I do not know how security would be ensured. I was thinking that whenever a particular player has a turn, they alter the game state and 开发者_JS百科then they broadcast this game state to the network (the other players in this game). However if the game state contains things like each players cards and the remaining cards in the deck for when a new card is revealed, how can it be ensured that particular players in the network cannot access this information and alter their play style in accordance with that knowledge.

According to this link it may not even be possible to ensure security for gaming in peer to peer network infrastructures and there's always going to be a risk of hacking?: https://cyrextech.net/security-explained-fear-the-peer-to-peer/

I know in blockchains, they ensure the validity of transactions with public/private key signatures, however this doesn't necessarily ensure security/confidentiality, just validity since it doesn't matter that the transactions are necessarily private.

Is there a way to algorithmically ensure that players cannot alter the game state to their will or is it just not possible to do this in p2p structure.