Smart Wallet

A LazorKit smart wallet is a cluster of on-chain accounts controlled by the LazorKit program. The owner authenticates via WebAuthn (passkey) or Ed25519 — no seed phrase, no browser extension, no private key storage in your app.

Account structure

Wallet PDA

Minimal 8-byte account. Chosen by a 32-byte user_seed at creation. You don't need to store it client-side — look it up via findWalletsByAuthority(credentialIdHash).

Vault PDA

Zero-data account that holds SOL and tokens. The program signs for it during Execute. No rent deposit required — the vault is itself a PDA with no allocated data.

Authority PDA

One PDA per authorised key. Header (48 bytes) + tail:

• authority_type — Ed25519 (0) or Secp256r1 (1)
• role — Owner (0) / Admin (1) / Spender (2)
• counter — monotonic u32 for Secp256r1 replay protection
• tail — 32-byte pubkey for Ed25519; credential_id_hash(32) + compressed_pubkey(33) + rpId_hash(32) for Secp256r1 (fixed 97 bytes)

Because each authority has its own PDA, different authorities on the same wallet execute in parallel — the only writable account during Execute is the caller's own authority PDA (counter increment). Wallet and vault are read-only.

Authentication

Secp256r1 (Passkey)

WebAuthn credentials bound to the device's Secure Enclave (Face ID, Touch ID, Windows Hello, security keys). The credential never leaves the device. On-chain verification uses the native Secp256r1 precompile and enforces:

• Odometer counter — monotonic u32 per authority. Client submits stored_counter + 1. Committed only after successful verification.
• Slot freshness — auth payload slot must be within 150 slots of Clock::get().
• CPI protection — stack height check prevents passkey auth via CPI.
• Accounts hash — signed payload binds to all account pubkeys, preventing account-swap attacks.

Ed25519

Standard Solana keypair. Verified by the Solana runtime. No counter required — Solana's tx-level duplicate detection handles replay.

Roles

See RBAC for the full permission breakdown.

Wallet lifecycle

Create

const { instructions, walletPda, vaultPda, authorityPda } = await client.createWallet({
  payer: payer.publicKey,
  userSeed: crypto.randomBytes(32),
  owner: {
    type: 'secp256r1',
    credentialIdHash,     // 32-byte SHA256 of WebAuthn credential ID
    compressedPubkey,     // 33-byte compressed Secp256r1 public key
    rpId: 'your-app.com',
  },
});

Creates Wallet PDA, Vault PDA, and the first Authority PDA in one transaction.

Look up a returning user

No need to persist walletPda client-side:

const [wallet] = await client.findWalletsByAuthority(credentialIdHash);
// { walletPda, authorityPda, vaultPda, role, authorityType }

Add authority

Adds another key. Owner can add any role; Admin can only add Spender.

Remove authority

Closes the authority PDA and refunds rent to a specified destination. Prevents self-removal and removal of the last owner.

Transfer ownership

Atomically closes the old owner PDA and creates a new owner PDA. Refunds the old owner's rent to an explicit destination.

Costs

At $150/SOL, wallet creation is ~$0.36–$0.41. Session setup is ~$0.22, with subsequent session-signed executes at ~$0.00075 each.

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