# ISelfPermit

Functionality to call permit on any EIP-2612-compliant token for use in the route

### Functions[​](https://docs.uniswap.org/contracts/v3/reference/periphery/interfaces/ISelfPermit#functions) <a href="#functions" id="functions"></a>

#### selfPermit[​](https://docs.uniswap.org/contracts/v3/reference/periphery/interfaces/ISelfPermit#selfpermit) <a href="#selfpermit" id="selfpermit"></a>

```solidity
  function selfPermit(
    address token,
    uint256 value,
    uint256 deadline,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external
```

Permits this contract to spend a given token from `msg.sender`

The `owner` is always msg.sender and the `spender` is always address(this).

**Parameters:**[**​**](https://docs.uniswap.org/contracts/v3/reference/periphery/interfaces/ISelfPermit#parameters)

| Name       | Type    | Description                                                                     |
| ---------- | ------- | ------------------------------------------------------------------------------- |
| `token`    | address | The address of the token spent                                                  |
| `value`    | uint256 | The amount that can be spent of token                                           |
| `deadline` | uint256 | A timestamp, the current blocktime must be less than or equal to this timestamp |
| `v`        | uint8   | Must produce valid secp256k1 signature from the holder along with `r` and `s`   |
| `r`        | bytes32 | Must produce valid secp256k1 signature from the holder along with `v` and `s`   |
| `s`        | bytes32 | Must produce valid secp256k1 signature from the holder along with `r` and `v`   |

#### selfPermitIfNecessary[​](https://docs.uniswap.org/contracts/v3/reference/periphery/interfaces/ISelfPermit#selfpermitifnecessary) <a href="#selfpermitifnecessary" id="selfpermitifnecessary"></a>

```solidity
  function selfPermitIfNecessary(
    address token,
    uint256 value,
    uint256 deadline,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external
```

Permits this contract to spend a given token from `msg.sender`

The `owner` is always msg.sender and the `spender` is always address(this). Can be used instead of #selfPermit to prevent calls from failing due to a frontrun of a call to #selfPermit

**Parameters:**[**​**](https://docs.uniswap.org/contracts/v3/reference/periphery/interfaces/ISelfPermit#parameters-1)

| Name       | Type    | Description                                                                     |
| ---------- | ------- | ------------------------------------------------------------------------------- |
| `token`    | address | The address of the token spent                                                  |
| `value`    | uint256 | The amount that can be spent of token                                           |
| `deadline` | uint256 | A timestamp, the current blocktime must be less than or equal to this timestamp |
| `v`        | uint8   | Must produce valid secp256k1 signature from the holder along with `r` and `s`   |
| `r`        | bytes32 | Must produce valid secp256k1 signature from the holder along with `v` and `s`   |
| `s`        | bytes32 | Must produce valid secp256k1 signature from the holder along with `r` and `v`   |

#### selfPermitAllowed[​](https://docs.uniswap.org/contracts/v3/reference/periphery/interfaces/ISelfPermit#selfpermitallowed) <a href="#selfpermitallowed" id="selfpermitallowed"></a>

```solidity
  function selfPermitAllowed(
    address token,
    uint256 nonce,
    uint256 expiry,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external
```

Permits this contract to spend the sender's tokens for permit signatures that have the `allowed` parameter

The `owner` is always msg.sender and the `spender` is always address(this)

**Parameters:**[**​**](https://docs.uniswap.org/contracts/v3/reference/periphery/interfaces/ISelfPermit#parameters-2)

| Name     | Type    | Description                                                                   |
| -------- | ------- | ----------------------------------------------------------------------------- |
| `token`  | address | The address of the token spent                                                |
| `nonce`  | uint256 | The current nonce of the owner                                                |
| `expiry` | uint256 | The timestamp at which the permit is no longer valid                          |
| `v`      | uint8   | Must produce valid secp256k1 signature from the holder along with `r` and `s` |
| `r`      | bytes32 | Must produce valid secp256k1 signature from the holder along with `v` and `s` |
| `s`      | bytes32 | Must produce valid secp256k1 signature from the holder along with `r` and `v` |

#### selfPermitAllowedIfNecessary[​](https://docs.uniswap.org/contracts/v3/reference/periphery/interfaces/ISelfPermit#selfpermitallowedifnecessary) <a href="#selfpermitallowedifnecessary" id="selfpermitallowedifnecessary"></a>

```solidity
  function selfPermitAllowedIfNecessary(
    address token,
    uint256 nonce,
    uint256 expiry,
    uint8 v,
    bytes32 r,
    bytes32 s
  ) external
```

Permits this contract to spend the sender's tokens for permit signatures that have the `allowed` parameter

The `owner` is always msg.sender and the `spender` is always address(this) Can be used instead of #selfPermitAllowed to prevent calls from failing due to a frontrun of a call to #selfPermitAllowed.

**Parameters:**[**​**](https://docs.uniswap.org/contracts/v3/reference/periphery/interfaces/ISelfPermit#parameters-3)

| Name     | Type    | Description                                                                   |
| -------- | ------- | ----------------------------------------------------------------------------- |
| `token`  | address | The address of the token spent                                                |
| `nonce`  | uint256 | The current nonce of the owner                                                |
| `expiry` | uint256 | The timestamp at which the permit is no longer valid                          |
| `v`      | uint8   | Must produce valid secp256k1 signature from the holder along with `r` and `s` |
| `r`      | bytes32 | Must produce valid secp256k1 signature from the holder along with `v` and `s` |
| `s`      | bytes32 | Must produce valid secp256k1 signature from the holder along with `r` and `v` |