Add Permit2Parsing lib (#64)

* add Permit2Parsing lib

* fix solidity version

* rename namings

* add memory versions

src/libraries/PermitParsing.sol

@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: Apache 2
+
+pragma solidity ^0.8.4;
+
+import {BytesParsing} from "wormhole-sdk/libraries/BytesParsing.sol";
+
+library PermitParsing {
+  using BytesParsing for bytes;
+
+  uint constant SIGNATURE_SIZE = 65;
+
+  function asPermitUnchecked(
+    bytes memory params,
+    uint offset
+  ) internal pure returns (uint256, uint256, bytes32, bytes32, uint8, uint) {
+    uint256 value;
+    uint256 deadline;
+    bytes32 r;
+    bytes32 s;
+    uint8 v;
+    (value,    offset) = params.asUint256Unchecked(offset);
+    (deadline, offset) = params.asUint256Unchecked(offset);
+    (r,        offset) = params.asBytes32Unchecked(offset);
+    (s,        offset) = params.asBytes32Unchecked(offset);
+    (v,        offset) = params.asUint8Unchecked(offset);
+    return (value, deadline, r, s, v, offset);
+  }
+
+  function asPermitCdUnchecked(
+    bytes calldata params,
+    uint offset
+  ) internal pure returns (uint256, uint256, bytes32, bytes32, uint8, uint) {
+    uint256 value;
+    uint256 deadline;
+    bytes32 r;
+    bytes32 s;
+    uint8 v;
+    (value,    offset) = params.asUint256CdUnchecked(offset);
+    (deadline, offset) = params.asUint256CdUnchecked(offset);
+    (r,        offset) = params.asBytes32CdUnchecked(offset);
+    (s,        offset) = params.asBytes32CdUnchecked(offset);
+    (v,        offset) = params.asUint8CdUnchecked(offset);
+    return (value, deadline, r, s, v, offset);
+  }
+
+  function asPermit2PermitUnchecked(
+    bytes memory params,
+    uint offset
+  ) internal pure returns (uint160, uint48, uint48, uint256, bytes memory, uint) {
+    uint160 amount;
+    uint48 expiration;
+    uint48 nonce;
+    uint256 sigDeadline;
+    bytes memory signature;
+    (amount,      offset) = params.asUint160Unchecked(offset);
+    (expiration,  offset) = params.asUint48Unchecked(offset);
+    (nonce,       offset) = params.asUint48Unchecked(offset);
+    (sigDeadline, offset) = params.asUint256Unchecked(offset);
+    (signature,   offset) = params.sliceUnchecked(offset, SIGNATURE_SIZE);
+    return (amount, expiration, nonce, sigDeadline, signature, offset);
+  }
+
+  function asPermit2PermitCdUnchecked(
+    bytes calldata params,
+    uint offset
+  ) internal pure returns (uint160, uint48, uint48, uint256, bytes memory, uint) {
+    uint160 amount;
+    uint48 expiration;
+    uint48 nonce;
+    uint256 sigDeadline;
+    bytes memory signature;
+    (amount,      offset) = params.asUint160CdUnchecked(offset);
+    (expiration,  offset) = params.asUint48CdUnchecked(offset);
+    (nonce,       offset) = params.asUint48CdUnchecked(offset);
+    (sigDeadline, offset) = params.asUint256CdUnchecked(offset);
+    (signature,   offset) = params.sliceCdUnchecked(offset, SIGNATURE_SIZE);
+    return (amount, expiration, nonce, sigDeadline, signature, offset);
+  }
+
+  function asPermit2TransferUnchecked(
+    bytes memory params,
+    uint offset
+  ) internal pure returns (uint256, uint256, uint256, bytes memory, uint) {
+    uint256 amount;
+    uint256 nonce;
+    uint256 sigDeadline;
+    bytes memory signature;
+    (amount,      offset) = params.asUint256Unchecked(offset);
+    (nonce,       offset) = params.asUint256Unchecked(offset);
+    (sigDeadline, offset) = params.asUint256Unchecked(offset);
+    (signature,   offset) = params.sliceUnchecked(offset, SIGNATURE_SIZE);
+    return (amount, nonce, sigDeadline, signature, offset);
+  }
+
+  function asPermit2TransferCdUnchecked(
+    bytes calldata params,
+    uint offset
+  ) internal pure returns (uint256, uint256, uint256, bytes memory, uint) {
+    uint256 amount;
+    uint256 nonce;
+    uint256 sigDeadline;
+    bytes memory signature;
+    (amount,      offset) = params.asUint256CdUnchecked(offset);
+    (nonce,       offset) = params.asUint256CdUnchecked(offset);
+    (sigDeadline, offset) = params.asUint256CdUnchecked(offset);
+    (signature,   offset) = params.sliceCdUnchecked(offset, SIGNATURE_SIZE);
+    return (amount, nonce, sigDeadline, signature, offset);
+  }
+}