EigenCloud TEE¶

Clout Cards runs inside a Trusted Execution Environment (TEE) to provide cryptographic guarantees that the game logic is executed correctly and cannot be tampered with.

Build on EigenCloud

Want to build your own verifiable application with TEE security? EigenCloud makes it easy to deploy trustless backends with cryptographic guarantees. Get started at the EigenCloud Developer Docs.

What is a TEE?¶

A Trusted Execution Environment is a secure, isolated area of a processor that guarantees:

Confidentiality: Data inside the enclave cannot be read by anyone, including the server operator
Integrity: Code running inside cannot be modified
Attestation: The enclave can prove what code it's running

Google Confidential Spaces¶

Clout Cards is deployed on Google Confidential Spaces, which provides:

Feature	Description
Hardware-backed isolation	AMD SEV-SNP secure processor technology
Memory encryption	All enclave memory is encrypted
Remote attestation	Cryptographic proof of enclave integrity
No operator access	Even Google cannot access enclave data

The TEE Private Key¶

At the heart of Clout Cards' security model is a private key that never leaves the enclave:

┌─────────────────────────────────────────────────────┐
│              TEE Enclave (Confidential)             │
│                                                     │
│   ┌─────────────────────────────────────────────┐   │
│   │           TEE Private Key                   │   │
│   │   (Generated inside, never exported)        │   │
│   └─────────────────────────────────────────────┘   │
│                        │                            │
│                        ▼                            │
│   ┌─────────────────────────────────────────────┐   │
│   │         EIP-712 Signature Engine            │   │
│   │   - Signs game events                       │   │
│   │   - Signs withdrawal authorizations         │   │
│   └─────────────────────────────────────────────┘   │
│                                                     │
└─────────────────────────────────────────────────────┘

Key Properties¶

Generated inside the enclave - The private key is created when the TEE starts and never exists outside
Never exported - There is no mechanism to extract the key
Deterministic derivation - The same enclave code always produces the same key (via attestation-bound derivation)

What Gets Signed¶

Every significant action is signed by the TEE private key using EIP-712 typed signatures:

Game Events¶

Event Type	Signed Data
`hand_start`	Table, players, blinds, dealer position
`hand_action`	Action type, amount, player, hand state
`hand_end`	Winners, pot distribution, final hands
`join_table`	Player, seat, buy-in amount
`leave_table`	Player, seat, balance returned

Withdrawal Authorizations¶

Field	Description
Player address	Who can withdraw
Amount	How much (in gwei)
Nonce	Unique per withdrawal
Expiry	When signature expires

Verification¶

Anyone can verify that data was processed inside the TEE:

1. Get the TEE Public Key¶

The TEE's public key is derived from the private key and can be retrieved:

GET /teePublicKey

2. Verify Event Signatures¶

Each event in the database contains:

{
  "eventId": 1234,
  "kind": "hand_action",
  "payloadJson": "{...}",
  "digest": "0x...",
  "sigR": "0x...",
  "sigS": "0x...",
  "sigV": 27,
  "teePubkey": "0x..."
}

Verify by: 1. Compute EIP-712 digest from payloadJson 2. Recover signer from (sigR, sigS, sigV) 3. Confirm recovered address matches teePubkey

3. Verify Attestation¶

Google Confidential Spaces provides attestation that proves: - The exact code running in the enclave - The enclave's integrity - The binding between the code and the TEE public key

Security Guarantees¶

Guarantee	How It's Achieved
Game logic integrity	Code runs in attested TEE
No card manipulation	RNG and dealing inside enclave
Withdrawal security	Only TEE can sign valid withdrawals
Audit trail	All events signed and verifiable
Operator honesty	Operator cannot forge signatures

Why This Matters¶

Without the TEE:

The server operator could manipulate game outcomes
Withdrawal signatures could be forged
There would be no proof that the game was fair

With the TEE:

Provably fair - Every action is signed by tamper-proof code
Trustless - You don't need to trust the operator
Verifiable - Anyone can verify the signatures match the TEE
Secure - Private key cannot be extracted, even by the operator

EigenCloud Integration¶

Clout Cards uses EigenCloud for TEE deployment and management:

Simplified deployment to Google Confidential Spaces
Key management and attestation services
Monitoring and logging (without exposing sensitive data)

The combination of EigenCloud + Google Confidential Spaces provides enterprise-grade security for trustless game execution.