ISignatureTransfer

Handles ERC20 token transfers through signature based actions

Requires user's token approval on the Permit2 contract

InvalidAmount

error InvalidAmount(uint256 maxAmount)

Thrown when the requested amount for a transfer is larger than the permissioned amount

Parameters

LengthMismatch

error LengthMismatch()

Thrown when the number of tokens permissioned to a spender does not match the number of tokens being transferred

If the spender does not need to transfer the number of tokens permitted, the spender can request amount 0 to be transferred

UnorderedNonceInvalidation

event UnorderedNonceInvalidation(address owner, uint256 word, uint256 mask)

Emits an event when the owner successfully invalidates an unordered nonce.

TokenPermissions

The token and amount details for a transfer signed in the permit transfer signature

struct TokenPermissions {
  address token;
  uint256 amount;
}

PermitTransferFrom

The signed permit message for a single token transfer

struct PermitTransferFrom {
  struct ISignatureTransfer.TokenPermissions permitted;
  uint256 nonce;
  uint256 deadline;
}

SignatureTransferDetails

Specifies the recipient address and amount for batched transfers.

Recipients and amounts correspond to the index of the signed token permissions array. Reverts if the requested amount is greater than the permitted signed amount.

struct SignatureTransferDetails {
  address to;
  uint256 requestedAmount;
}

PermitBatchTransferFrom

Used to reconstruct the signed permit message for multiple token transfers

Do not need to pass in spender address as it is required that it is msg.sender Note that a user still signs over a spender address

struct PermitBatchTransferFrom {
  struct ISignatureTransfer.TokenPermissions[] permitted;
  uint256 nonce;
  uint256 deadline;
}

nonceBitmap

function nonceBitmap(address, uint256) external view returns (uint256)

A map from token owner address and a caller specified word index to a bitmap. Used to set bits in the bitmap to prevent against signature replay protection

Uses unordered nonces so that permit messages do not need to be spent in a certain order The mapping is indexed first by the token owner, then by an index specified in the nonce It returns a uint256 bitmap The index, or wordPosition is capped at type(uint248).max

permitTransferFrom

function permitTransferFrom(struct ISignatureTransfer.PermitTransferFrom permit, struct ISignatureTransfer.SignatureTransferDetails transferDetails, address owner, bytes signature) external

Transfers a token using a signed permit message

Reverts if the requested amount is greater than the permitted signed amount

Parameters

permitWitnessTransferFrom

function permitWitnessTransferFrom(struct ISignatureTransfer.PermitTransferFrom permit, struct ISignatureTransfer.SignatureTransferDetails transferDetails, address owner, bytes32 witness, string witnessTypeString, bytes signature) external

Transfers a token using a signed permit message Includes extra data provided by the caller to verify signature over

The witness type string must follow EIP712 ordering of nested structs and must include the TokenPermissions type definition Reverts if the requested amount is greater than the permitted signed amount

Parameters

permitTransferFrom

function permitTransferFrom(struct ISignatureTransfer.PermitBatchTransferFrom permit, struct ISignatureTransfer.SignatureTransferDetails[] transferDetails, address owner, bytes signature) external

Transfers multiple tokens using a signed permit message

Parameters

permitWitnessTransferFrom

function permitWitnessTransferFrom(struct ISignatureTransfer.PermitBatchTransferFrom permit, struct ISignatureTransfer.SignatureTransferDetails[] transferDetails, address owner, bytes32 witness, string witnessTypeString, bytes signature) external

Transfers multiple tokens using a signed permit message Includes extra data provided by the caller to verify signature over

The witness type string must follow EIP712 ordering of nested structs and must include the TokenPermissions type definition

Parameters

invalidateUnorderedNonces

function invalidateUnorderedNonces(uint256 wordPos, uint256 mask) external

Invalidates the bits specified in mask for the bitmap at the word position

The wordPos is maxed at type(uint248).max

Parameters