Private Swap - Veilify

function shieldedSwap(ShieldedSwapParams calldata params, bytes calldata proof)
    external nonReentrant whenNotPaused whenWithdrawalsNotPaused;

Params

struct ShieldedSwapParams {
    bytes32[6]     noteNullifiers;
    bytes32        txNullifier;
    bytes32        root;
    bytes32        noteChangeCommitment;
    bytes32        noteFeeChangeCommitment;
    bytes32        selector;
    SwapRouterArgs routerArgs;
    bytes32        receivingKeyCommitment;
    bytes32[9]     ciphertextChange;
    bytes32[9]     ciphertextFeeChange;
    bytes32[6]     ciphertextSwap;
    GasFee         gasFee;
    bytes32        nullifiersHash;
    bytes32        fee;
    bytes32        feeTokenAddress;
}

struct SwapRouterArgs {
    bytes32    amountIn;
    bytes32    amountOutMin;
    bytes32[4] path;
    bytes32    pathLength;
    bytes32    deadline;
}

Selectors

Selector	Router function	Input	Output
`0x38ed1739`	`swapExactTokensForTokens`	`path[0]`	`path[last]`
`0x7ff36ab5`	`swapExactETHForTokens`	ETH	`path[last]`
`0x18cbafe5`	`swapExactTokensForETH`	`path[0]`	ETH

VeilifySwap switches to the …SupportingFeeOnTransferTokens variant when the path includes a fee-on-transfer token. It measures the output by balance delta. Any other selector reverts with InvalidSwapSelector.

Execution

_checkSpend
deadline ≤ block.timestamp + 30 minutes (DeadlineTooFar)
amountOutMin ≠ 0 (ZeroAmountOutMin)
Verify 52 public inputs (VIRTUAL_CHAIN_ID, UNISWAP_V2_ROUTER, then params)
Spend nullifiers
Run the swap through VeilifySwap (delegatecall)
Build the output note from receivingKeyCommitment, amountOut, the output token and nullifiersHash
Insert output, change and fee-change notes
Pay fee to msg.sender
Emit ShieldedSwap

Event

event ShieldedSwap(
    bytes32 indexed txNullifier,
    bytes32 nullifiersHash,
    bytes32 noteOutCommitment,
    bytes32 noteChangeCommitment,
    bytes32 noteFeeChangeCommitment,
    uint256 amountIn,
    address tokenIn,
    uint256 amountOut,
    address tokenOut,
    uint256 fee,
    address feeTokenAddress
);