Initialize the privacy contract
fn initialize(env: soroban_sdk::Env) -> Result<(), ContractError>
Deposit assets into the privacy pool Creates a commitment that hides the amount and recipient
In production, commitment = Poseidon(amount, secret, nullifier, recipient) For this demo, we use SHA-256 as Poseidon host functions require the actual X-Ray upgrade
fn deposit(
env: soroban_sdk::Env,
caller: soroban_sdk::Address,
token: soroban_sdk::Address,
amount: i128,
commitment: soroban_sdk::BytesN<32>,
) -> Result
Withdraw assets from the privacy pool Uses ZK proof to prove ownership without revealing which deposit is being spent
Parameters:
fn withdraw(
env: soroban_sdk::Env,
proof: soroban_sdk::Bytes,
nullifier: soroban_sdk::BytesN<32>,
recipient: soroban_sdk::Address,
amount: i128,
token: soroban_sdk::Address,
) -> Result<(), ContractError>
Make a shielded transfer - deposit and withdraw in one transaction This provides maximum privacy by hiding both sender and amount in contract parameters
fn shielded_transfer(
env: soroban_sdk::Env,
sender: soroban_sdk::Address,
token: soroban_sdk::Address,
commitment: soroban_sdk::BytesN<32>,
proof: soroban_sdk::Bytes,
nullifier: soroban_sdk::BytesN<32>,
recipient: soroban_sdk::Address,
deposit_amount: i128,
withdraw_amount: i128,
) -> Result<(), ContractError>
Query if a nullifier has been used (public, for transparency)
fn is_nullifier_used_public(
env: soroban_sdk::Env,
nullifier: soroban_sdk::BytesN<32>,
) -> bool
Get current commitment count (public, for tree building)
fn get_commitment_count(env: soroban_sdk::Env) -> u32
Get commitment by index (public, for merkle tree verification)
fn get_commitment(env: soroban_sdk::Env, index: u32) -> Option>
Create a commitment using Poseidon hash (ZK-friendly) commitment = Poseidon(amount, secret, nullifier, recipient_hash)
fn create_commitment_hash(
env: soroban_sdk::Env,
amount: i128,
secret: soroban_sdk::BytesN<32>,
nullifier: soroban_sdk::BytesN<32>,
recipient: soroban_sdk::Address,
) -> soroban_sdk::BytesN<32>
Create a nullifier using Poseidon hash nullifier = Poseidon(secret, index)
fn create_nullifier_hash(
env: soroban_sdk::Env,
secret: soroban_sdk::BytesN<32>,
commitment_index: u32,
) -> soroban_sdk::BytesN<32>