> 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/univ4-hook/libraries/library.signatureverification.md).

# SignatureVerification

[Git Source](https://github.com/propeller-heads/turbine/blob/90514973167f1eb25cb9eb7756354fb3de34824d/src/univ4-hook/libraries/SignatureVerification.sol)

Library for verifying signatures using ECDSA and ERC-1271

Copied from <https://github.com/Uniswap/permit2/blob/cc56ad0f3439c502c246fc5cfcc3db92bb8b7219/src/libraries/SignatureVerification.sol>

## State Variables

### UPPER\_BIT\_MASK

```solidity
bytes32 constant UPPER_BIT_MASK = (0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
```

## Functions

### verify

```solidity
function verify(bytes calldata signature, bytes32 hash, address claimedSigner) internal view;
```

## Errors

### InvalidSignatureLength

Thrown when the passed in signature is not a valid length

```solidity
error InvalidSignatureLength();
```

### InvalidSignature

Thrown when the recovered signer is equal to the zero address

```solidity
error InvalidSignature();
```

### InvalidSigner

Thrown when the recovered signer does not equal the claimedSigner

```solidity
error InvalidSigner();
```

### InvalidContractSignature

Thrown when the recovered contract signature is incorrect

```solidity
error InvalidContractSignature();
```


---

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