API Reference

StealthKeypair

A spending keypair derived for a specific stealth payment. Used to sign transactions and claim funds from stealth addresses.

Structure

cloak_sdk::spend

rust

pub struct StealthKeypair {
    keypair: Keypair,  // Solana keypair (internal)
}

// Security notes:
// - Implements Zeroize for secure memory cleanup
// - No Serialize trait (prevents accidental persistence)
// - No Debug output of private keys

Methods

`derive(meta, ephemeral_pubkey) → Result<StealthKeypair>`

Derive the spending keypair for a payment from the meta-address and the ephemeral public key published on-chain.

let keypair = StealthKeypair::derive(&meta, &ephemeral_pubkey)?;
assert_eq!(keypair.address(), expected_stealth_address);

`from_payment(meta, payment) → Result<StealthKeypair>`

Convenience method that extracts the ephemeral key from a DetectedPayment.

let keypair = StealthKeypair::from_payment(&meta, &detected_payment)?;

`address() → Pubkey`

Get the Solana public key (stealth address) for this keypair.

let stealth_addr = keypair.address();

`pubkey_bytes() → [u8; 32]`

Get the raw 32-byte public key.

`to_solana_keypair() → Result<Keypair>`

Convert to a Solana SDK Keypair for signing transactions.

let solana_kp = keypair.to_solana_keypair()?;

`to_bytes() → [u8; 64]`

Get the raw 64 bytes (32 secret + 32 public).

Example: SOL transfer

spend_sol.rs

rust

use cloak_sdk::StealthKeypair;
use solana_sdk::{transaction::Transaction, system_instruction};

let keypair = StealthKeypair::derive(&meta, &ephemeral_pubkey)?;
let solana_kp = keypair.to_solana_keypair()?;

// Transfer all SOL to destination
let balance = client.get_balance(&keypair.address())?;
let ix = system_instruction::transfer(
    &keypair.address(),
    &destination,
    balance - 5000, // leave for fees
);

let tx = Transaction::new_signed_with_payer(
    &[ix],
    Some(&keypair.address()),
    &[&solana_kp],
    client.get_latest_blockhash()?,
);
client.send_and_confirm_transaction(&tx)?;

Example: SPL token transfer

spend_spl.rs

rust

use spl_token::instruction::transfer as spl_transfer;
use spl_associated_token_account::get_associated_token_address;

let source_ata = get_associated_token_address(&keypair.address(), &mint);
let dest_ata = get_associated_token_address(&destination, &mint);

let ix = spl_transfer(
    &spl_token::id(),
    &source_ata,
    &dest_ata,
    &keypair.address(),
    &[],
    token_amount,
)?;

let tx = Transaction::new_signed_with_payer(
    &[ix],
    Some(&keypair.address()),
    &[&solana_kp],
    recent_blockhash,
);