fTokenEIP2612Withdrawals

fTokens support EIP-2612 permit approvals via signature so this contract implements withdrawals (withdraw / redeem) with signature used for approval of the fToken shares.

Functions

_allowViaPermitEIP2612

creates sharesToPermit_ allowance for owner_ via EIP2612 deadline_ and signature_

function _allowViaPermitEIP2612(address owner_, uint256 sharesToPermit_, uint256 deadline_, bytes calldata signature_)
    internal;

withdraw amount of assets_ with ERC-2612 permit signature for fToken approval. owner_ signs ERC-2612 permit signature_ to give allowance of fTokens to msg.sender. Note there might be tiny inaccuracies between requested assets_ and actually received assets amount. allowance via signature (sharesToPermit_) should cover previewWithdraw(assets_) plus a little buffer to avoid revert. Inherent trust assumption that msg.sender will set receiver_ and maxSharesBurn_ as owner_ intends (which is always the case when giving allowance to some spender).

function withdrawWithSignature(
    uint256 sharesToPermit_,
    uint256 assets_,
    address receiver_,
    address owner_,
    uint256 maxSharesBurn_,
    uint256 deadline_,
    bytes calldata signature_
) external virtual nonReentrant returns (uint256 shares_);

Parameters

Name	Type	Description
`sharesToPermit_`	`uint256`	shares amount to use for EIP2612 permit(). Should cover `previewWithdraw(assets_)` + small buffer.
`assets_`	`uint256`	amount of assets to withdraw
`receiver_`	`address`	receiver of withdrawn assets
`owner_`	`address`	owner to withdraw from (must be signature signer)
`maxSharesBurn_`	`uint256`	maximum accepted amount of shares burned
`deadline_`	`uint256`	deadline for signature validity
`signature_`	`bytes`	packed signature of signing the EIP712 hash for ERC-2612 permit

Returns

Name	Type	Description
`shares_`	`uint256`	burned shares amount

redeemWithSignature

redeem amount of shares_ with ERC-2612 permit signature for fToken approval. owner_ signs ERC-2612 permit signature_ to give allowance of fTokens to msg.sender. Note there might be tiny inaccuracies between requested shares_ to redeem and actually burned shares. allowance via signature must cover shares_ plus a tiny buffer. Inherent trust assumption that msg.sender will set receiver_ and minAmountOut_ as owner_ intends (which is always the case when giving allowance to some spender). Recommended to use withdraw() over redeem because it is more gas efficient and can set specific amount.

function redeemWithSignature(
    uint256 shares_,
    address receiver_,
    address owner_,
    uint256 minAmountOut_,
    uint256 deadline_,
    bytes calldata signature_
) external virtual nonReentrant returns (uint256 assets_);

Parameters

Name	Type	Description
`shares_`	`uint256`	amount of shares to redeem
`receiver_`	`address`	receiver of withdrawn assets
`owner_`	`address`	owner to withdraw from (must be signature signer)
`minAmountOut_`	`uint256`	minimum accepted amount of assets withdrawn
`deadline_`	`uint256`	deadline for signature validity
`signature_`	`bytes`	packed signature of signing the EIP712 hash for ERC-2612 permit

Returns

Name	Type	Description
`assets_`	`uint256`	withdrawn assets amount

Main.solfTokenEIP2612Deposits

Main.solfTokenPermit2Deposits