> For the complete documentation index, see [llms.txt](https://docs.turbine.exchange/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.turbine.exchange/reference/contracts/solidity-documentation/interfaces/interface.iallowancetransfer.md). # IAllowanceTransfer [Git Source](https://github.com/propeller-heads/turbine/blob/90514973167f1eb25cb9eb7756354fb3de34824d/src/interfaces/IAllowanceTransfer.sol) **Inherits:** [IEIP712](https://github.com/propeller-heads/turbine-docs/blob/master/src/interfaces/IEIP712.sol/interface.IEIP712.md) **Title:** AllowanceTransfer Handles ERC20 token permissions through signature based allowance setting and ERC20 token transfers by checking allowed amounts Requires user's token approval on the Permit2 contract ## Functions ### allowance A mapping from owner address to token address to spender address to PackedAllowance struct, which contains details and conditions of the approval. The mapping is indexed in the above order see: allowance\[ownerAddress]\[tokenAddress]\[spenderAddress] The packed slot holds the allowed amount, expiration at which the allowed amount is no longer valid, and current nonce thats updated on any signature based approvals. ```solidity function allowance( address user, address token, address spender ) external view returns (uint160 amount, uint48 expiration, uint48 nonce); ``` ### approve Approves the spender to use up to amount of the specified token up until the expiration The packed allowance also holds a nonce, which will stay unchanged in approve Setting amount to type(uint160).max sets an unlimited approval ```solidity function approve(address token, address spender, uint160 amount, uint48 expiration) external; ``` **Parameters** | Name | Type | Description | | ------------ | --------- | ------------------------------------------------------ | | `token` | `address` | The token to approve | | `spender` | `address` | The spender address to approve | | `amount` | `uint160` | The approved amount of the token | | `expiration` | `uint48` | The timestamp at which the approval is no longer valid | ### permit Permit a spender to a given amount of the owners token via the owner's EIP-712 signature May fail if the owner's nonce was invalidated in-flight by invalidateNonce ```solidity function permit(address owner, PermitSingle memory permitSingle, bytes calldata signature) external; ``` **Parameters** | Name | Type | Description | | -------------- | -------------- | -------------------------------------------------------------- | | `owner` | `address` | The owner of the tokens being approved | | `permitSingle` | `PermitSingle` | Data signed over by the owner specifying the terms of approval | | `signature` | `bytes` | The owner's signature over the permit data | ### permit Permit a spender to the signed amounts of the owners tokens via the owner's EIP-712 signature May fail if the owner's nonce was invalidated in-flight by invalidateNonce ```solidity function permit(address owner, PermitBatch memory permitBatch, bytes calldata signature) external; ``` **Parameters** | Name | Type | Description | | ------------- | ------------- | -------------------------------------------------------------- | | `owner` | `address` | The owner of the tokens being approved | | `permitBatch` | `PermitBatch` | Data signed over by the owner specifying the terms of approval | | `signature` | `bytes` | The owner's signature over the permit data | ### transferFrom Transfer approved tokens from one address to another Requires the from address to have approved at least the desired amount of tokens to msg.sender. ```solidity function transferFrom(address from, address to, uint160 amount, address token) external; ``` **Parameters** | Name | Type | Description | | -------- | --------- | ----------------------------------- | | `from` | `address` | The address to transfer from | | `to` | `address` | The address of the recipient | | `amount` | `uint160` | The amount of the token to transfer | | `token` | `address` | The token address to transfer | ### transferFrom Transfer approved tokens in a batch Requires the from addresses to have approved at least the desired amount of tokens to msg.sender. ```solidity function transferFrom(AllowanceTransferDetails[] calldata transferDetails) external; ``` **Parameters** | Name | Type | Description | | ----------------- | ---------------------------- | ------------------------------------------------------------------ | | `transferDetails` | `AllowanceTransferDetails[]` | Array of owners, recipients, amounts, and tokens for the transfers | ### lockdown Enables performing a "lockdown" of the sender's Permit2 identity by batch revoking approvals ```solidity function lockdown(TokenSpenderPair[] calldata approvals) external; ``` **Parameters** | Name | Type | Description | | ----------- | -------------------- | ----------------------------- | | `approvals` | `TokenSpenderPair[]` | Array of approvals to revoke. | ### invalidateNonces Invalidate nonces for a given (token, spender) pair Can't invalidate more than 2\*\*16 nonces per transaction. ```solidity function invalidateNonces(address token, address spender, uint48 newNonce) external; ``` **Parameters** | Name | Type | Description | | ---------- | --------- | ---------------------------------------------------------- | | `token` | `address` | The token to invalidate nonces for | | `spender` | `address` | The spender to invalidate nonces for | | `newNonce` | `uint48` | The new nonce to set. Invalidates all nonces less than it. | ## Events ### NonceInvalidation Emits an event when the owner successfully invalidates an ordered nonce. ```solidity event NonceInvalidation( address indexed owner, address indexed token, address indexed spender, uint48 newNonce, uint48 oldNonce ); ``` ### Approval Emits an event when the owner successfully sets permissions on a token for the spender. ```solidity event Approval( address indexed owner, address indexed token, address indexed spender, uint160 amount, uint48 expiration ); ``` ### Permit Emits an event when the owner successfully sets permissions using a permit signature on a token for the spender. ```solidity event Permit( address indexed owner, address indexed token, address indexed spender, uint160 amount, uint48 expiration, uint48 nonce ); ``` ### Lockdown Emits an event when the owner sets the allowance back to 0 with the lockdown function. ```solidity event Lockdown(address indexed owner, address token, address spender); ``` ## Errors ### AllowanceExpired Thrown when an allowance on a token has expired. ```solidity error AllowanceExpired(uint256 deadline); ``` **Parameters** | Name | Type | Description | | ---------- | --------- | ------------------------------------------------------------ | | `deadline` | `uint256` | The timestamp at which the allowed amount is no longer valid | ### InsufficientAllowance Thrown when an allowance on a token has been depleted. ```solidity error InsufficientAllowance(uint256 amount); ``` **Parameters** | Name | Type | Description | | -------- | --------- | -------------------------- | | `amount` | `uint256` | The maximum amount allowed | ### ExcessiveInvalidation Thrown when too many nonces are invalidated. ```solidity error ExcessiveInvalidation(); ``` ## Structs ### PermitDetails The permit data for a token ```solidity struct PermitDetails { // ERC20 token address address token; // the maximum amount allowed to spend uint160 amount; // timestamp at which a spender's token allowances become invalid uint48 expiration; // an incrementing value indexed per owner,token,and spender for each signature uint48 nonce; } ``` ### PermitSingle The permit message signed for a single token allowance ```solidity struct PermitSingle { // the permit data for a single token alownce PermitDetails details; // address permissioned on the allowed tokens address spender; // deadline on the permit signature uint256 sigDeadline; } ``` ### PermitBatch The permit message signed for multiple token allowances ```solidity struct PermitBatch { // the permit data for multiple token allowances PermitDetails[] details; // address permissioned on the allowed tokens address spender; // deadline on the permit signature uint256 sigDeadline; } ``` ### PackedAllowance The saved permissions This info is saved per owner, per token, per spender and all signed over in the permit message Setting amount to type(uint160).max sets an unlimited approval ```solidity struct PackedAllowance { // amount allowed uint160 amount; // permission expiry uint48 expiration; // an incrementing value indexed per owner,token,and spender for each signature uint48 nonce; } ``` ### TokenSpenderPair A token spender pair. ```solidity struct TokenSpenderPair { // the token the spender is approved address token; // the spender address address spender; } ``` ### AllowanceTransferDetails Details for a token transfer. ```solidity struct AllowanceTransferDetails { // the owner of the token address from; // the recipient of the token address to; // the amount of the token uint160 amount; // the token to be transferred address token; } ``` --- # Agent Instructions This documentation is published with GitBook. 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