Solana Crash Game Vault System

A production-ready Solana smart contract for a Crash game vault system, built using the Anchor framework.

Features

• Game authority management through PDAs
• Secure deposit/withdrawal system with SOL
• On-chain user balance tracking
• Bet placement and resolution
• Admin-only controls for resolving bets

Smart Contract Instructions

1. initialize(authority)

   • Creates the game authority account (PDA) with the signer as the admin.

2. deposit(user, amount)

   • Transfers SOL from the user wallet to a vault PDA.
   • Increases the user's on-chain balance (stored in a PDA).

3. withdraw(user)

   • Transfers the full balance back to the user's wallet.
   • Resets their on-chain balance to 0.

4. place_bet(user, amount)

   • Deducts SOL from the user's on-chain balance.

5. resolve_bet(user, win_amount)

   • Admin-only function. Adds winnings to the user's balance.

Technical Architecture

• Vault PDA: [b"vault"]
• User Balance PDA: [user_pubkey, b"balance"]
• Game Authority PDA: game_authority initialized via initialize.

Security Features

• Reentrancy protection by zeroing balance before withdrawals
• Overflow/underflow prevention with checked math operations
• Unauthorized access prevention with Signer and authority checks

Testing

The contract includes comprehensive tests for all instructions:

• Test deposit (check SOL moved + balance increased)
• Test withdraw (check SOL returned + balance reset)
• Test place_bet (balance deducted)
• Test resolve_bet (admin adds winnings)

Usage

For admin operations (like resolve_bet), use the generated admin.json keypair in the /tests directory.

License

MIT