Key Derivation

Veilify keys are derived from an EIP-712 signature, not stored. The same wallet signing the same typed data always yields the same keys.

The signed message

{
  "domain": { "name": "Veilify", "version": "1", "chainId": <chain id> },
  "primaryType": "KeyDerivation",
  "types": {
    "KeyDerivation": [
      { "name": "purpose",    "type": "string"  },
      { "name": "account",    "type": "address" },
      { "name": "keyVersion", "type": "uint32"  }
    ]
  },
  "message": {
    "purpose": "Derive view-only keys for your Veilify account",
    "account": "<lowercased 0x address>",
    "keyVersion": 1
  }
}

account must be a 20-byte hex address. It is lowercased before signing.
chainId must be a positive integer.
keyVersion is an integer in [1, 2³²). It defaults to 1.

The exact schema is pinned per deployment. Changing any field produces different keys, and existing notes become invisible. Never mix signing schemas within one deployment.

Key hierarchy

Key	Secret?	Use
pk `(pkX, pkY)`	Public	The wallet’s secp256k1 public key. `keccak256(pkX ‖ pkY)` is your address.
nk nullifying key	Secret	Derives note and transaction nullifiers
pnk public nullifying key	Public	`Poseidon2(nk)`. Published in the inbox key.
ivk incoming viewing key	Secret	Trial-decrypts incoming notes
ovk outgoing viewing key	Secret	Recovers notes you sent
ek encryption key	Public	`ivk · G` on Grumpkin. Senders encrypt to it.

Viewing key = (pk, nk, ivk, ovk). It reads everything but spends nothing. Spending also needs a fresh wallet signature.

Inbox key

The public half, registered on-chain once:

struct ReceivingKey {
    bytes32 pkX;
    bytes32 pkY;
    bytes32 keyData;   // first 20 bytes = owner address
    bytes32 pnk;
    bytes32 ekX;
    bytes32 ekY;
}

Its hash is the key-registry leaf:

fields[0..2] = pack31(pkX ‖ pkY ‖ keyData[0:29])   // 93 bytes → 3 field elements, little-endian
fields[3]    = pnk
fields[4]    = ekX
fields[5]    = ekY
rkHash       = Poseidon2.hashMany(fields)

See Key Registry for the on-chain checks.

Protocol Specification

Circuits

The signed message

Key hierarchy

Inbox key

​The signed message

​Key hierarchy

​Inbox key

The signed message

Key hierarchy

Inbox key