// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity 0.7.6;
// ============ Internal Imports ============
import {BridgeMessage} from "./BridgeMessage.sol";
import {IBridgeToken} from "./interfaces/IBridgeToken.sol";
import {ERC20} from "./vendored/OZERC20.sol";
// ============ External Imports ============
import {Version0} from "@nomad-xyz/contracts-core/contracts/Version0.sol";
import {TypeCasts} from "@nomad-xyz/contracts-core/contracts/XAppConnectionManager.sol";
import {OwnableUpgradeable} from "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
contract BridgeToken is Version0, IBridgeToken, OwnableUpgradeable, ERC20 {
// ============ Immutables ============
// Immutables used in EIP 712 structured data hashing & signing
// https://eips.ethereum.org/EIPS/eip-712
bytes32 public immutable _PERMIT_TYPEHASH =
keccak256(
"Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"
);
bytes32 private immutable _EIP712_STRUCTURED_DATA_VERSION =
keccak256(bytes("1"));
uint16 private immutable _EIP712_PREFIX_AND_VERSION = uint16(0x1901);
// ============ Public Storage ============
mapping(address => uint256) public nonces;
/// @dev hash commitment to the name/symbol/decimals
bytes32 public override detailsHash;
// ============ Upgrade Gap ============
uint256[48] private __GAP; // gap for upgrade safety
// ============ Initializer ============
function initialize() public override initializer {
__Ownable_init();
}
// ============ Events ============
event UpdateDetails(
string indexed name,
string indexed symbol,
uint8 indexed decimals
);
// ============ External Functions ============
/**
* @notice Destroys `_amnt` tokens from `_from`, reducing the
* total supply.
* @dev Emits a {Transfer} event with `to` set to the zero address.
* Requirements:
* - `_from` cannot be the zero address.
* - `_from` must have at least `_amnt` tokens.
* @param _from The address from which to destroy the tokens
* @param _amnt The amount of tokens to be destroyed
*/
function burn(address _from, uint256 _amnt) external override onlyOwner {
_burn(_from, _amnt);
}
/** @notice Creates `_amnt` tokens and assigns them to `_to`, increasing
* the total supply.
* @dev Emits a {Transfer} event with `from` set to the zero address.
* Requirements:
* - `to` cannot be the zero address.
* @param _to The destination address
* @param _amnt The amount of tokens to be minted
*/
function mint(address _to, uint256 _amnt) external override onlyOwner {
_mint(_to, _amnt);
}
/** @notice allows the owner to set the details hash commitment.
* @param _detailsHash the new details hash.
*/
function setDetailsHash(bytes32 _detailsHash) external override onlyOwner {
if (detailsHash != _detailsHash) {
detailsHash = _detailsHash;
}
}
/**
* @notice Set the details of a token
* @param _newName The new name
* @param _newSymbol The new symbol
* @param _newDecimals The new decimals
*/
function setDetails(
string calldata _newName,
string calldata _newSymbol,
uint8 _newDecimals
) external override {
bool _isFirstDetails = bytes(token.name).length == 0 &&
bytes(token.symbol).length == 0 &&
token.decimals == 0;
// 0 case is the initial deploy. We allow the deploying registry to set
// these once. After the first transfer is made, detailsHash will be
// set, allowing anyone to supply correct name/symbols/decimals
require(
_isFirstDetails ||
BridgeMessage.getDetailsHash(
_newName,
_newSymbol,
_newDecimals
) ==
detailsHash,
"!committed details"
);
// careful with naming convention change here
token.name = _newName;
token.symbol = _newSymbol;
token.decimals = _newDecimals;
if (!_isFirstDetails) {
emit UpdateDetails(_newName, _newSymbol, _newDecimals);
}
}
/**
* @notice Sets approval from owner to spender to value
* as long as deadline has not passed
* by submitting a valid signature from owner
* Uses EIP 712 structured data hashing & signing
* https://eips.ethereum.org/EIPS/eip-712
* @param _owner The account setting approval & signing the message
* @param _spender The account receiving approval to spend owner's tokens
* @param _value The amount to set approval for
* @param _deadline The timestamp before which the signature must be submitted
* @param _v ECDSA signature v
* @param _r ECDSA signature r
* @param _s ECDSA signature s
*/
function permit(
address _owner,
address _spender,
uint256 _value,
uint256 _deadline,
uint8 _v,
bytes32 _r,
bytes32 _s
) external {
require(block.timestamp <= _deadline, "ERC20Permit: expired deadline");
require(_owner != address(0), "ERC20Permit: owner zero address");
uint256 _nonce = nonces[_owner];
bytes32 _hashStruct = keccak256(
abi.encode(
_PERMIT_TYPEHASH,
_owner,
_spender,
_value,
_nonce,
_deadline
)
);
bytes32 _digest = keccak256(
abi.encodePacked(
_EIP712_PREFIX_AND_VERSION,
domainSeparator(),
_hashStruct
)
);
address _signer = ecrecover(_digest, _v, _r, _s);
require(_signer == _owner, "ERC20Permit: invalid signature");
nonces[_owner] = _nonce + 1;
_approve(_owner, _spender, _value);
}
// ============ Public Functions ============
/**
* @dev silence the compiler being dumb
*/
function balanceOf(address _account)
public
view
override(IBridgeToken, ERC20)
returns (uint256)
{
return ERC20.balanceOf(_account);
}
/**
* @dev Returns the name of the token.
*/
function name() public view override returns (string memory) {
return token.name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view override returns (string memory) {
return token.symbol;
}
/**
* @dev Returns the number of decimals used to get its user representation.
* For example, if `decimals` equals `2`, a balance of `505` tokens should
* be displayed to a user as `5,05` (`505 / 10 ** 2`).
* Tokens usually opt for a value of 18, imitating the relationship between
* Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
* called.
* NOTE: This information is only used for _display_ purposes: it in
* no way affects any of the arithmetic of the contract, including
* {IERC20-balanceOf} and {IERC20-transfer}.
*/
function decimals() public view override returns (uint8) {
return token.decimals;
}
/**
* @dev This is ALWAYS calculated at runtime
* because the token name may change
*/
function domainSeparator() public view returns (bytes32) {
uint256 _chainId;
assembly {
_chainId := chainid()
}
return
keccak256(
abi.encode(
keccak256(
"EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"
),
keccak256(bytes(token.name)),
_EIP712_STRUCTURED_DATA_VERSION,
_chainId,
address(this)
)
);
}
// required for solidity inheritance
function transferOwnership(address _newOwner)
public
override(IBridgeToken, OwnableUpgradeable)
onlyOwner
{
OwnableUpgradeable.transferOwnership(_newOwner);
}
/**
* @dev should be impossible to renounce ownership;
* we override OpenZeppelin OwnableUpgradeable's
* implementation of renounceOwnership to make it a no-op
*/
function renounceOwnership() public override onlyOwner {
// do nothing
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "../utils/ContextUpgradeable.sol";
import "../proxy/Initializable.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract OwnableUpgradeable is Initializable, ContextUpgradeable {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
function __Ownable_init() internal initializer {
__Context_init_unchained();
__Ownable_init_unchained();
}
function __Ownable_init_unchained() internal initializer {
address msgSender = _msgSender();
_owner = msgSender;
emit OwnershipTransferred(address(0), msgSender);
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
emit OwnershipTransferred(_owner, address(0));
_owner = address(0);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
require(newOwner != address(0), "Ownable: new owner is the zero address");
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
uint256[49] private __gap;
}
// SPDX-License-Identifier: MIT
// solhint-disable-next-line compiler-version
pragma solidity >=0.4.24 <0.8.0;
import "../utils/AddressUpgradeable.sol";
/**
* @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
* behind a proxy. Since a proxied contract can't have a constructor, it's common to move constructor logic to an
* external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
* function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
*
* TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
* possible by providing the encoded function call as the `_data` argument to {UpgradeableProxy-constructor}.
*
* CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
* that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
*/
abstract contract Initializable {
/**
* @dev Indicates that the contract has been initialized.
*/
bool private _initialized;
/**
* @dev Indicates that the contract is in the process of being initialized.
*/
bool private _initializing;
/**
* @dev Modifier to protect an initializer function from being invoked twice.
*/
modifier initializer() {
require(_initializing || _isConstructor() || !_initialized, "Initializable: contract is already initialized");
bool isTopLevelCall = !_initializing;
if (isTopLevelCall) {
_initializing = true;
_initialized = true;
}
_;
if (isTopLevelCall) {
_initializing = false;
}
}
/// @dev Returns true if and only if the function is running in the constructor
function _isConstructor() private view returns (bool) {
return !AddressUpgradeable.isContract(address(this));
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.2 <0.8.0;
/**
* @dev Collection of functions related to the address type
*/
library AddressUpgradeable {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.
uint256 size;
// solhint-disable-next-line no-inline-assembly
assembly { size := extcodesize(account) }
return size > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
// solhint-disable-next-line avoid-low-level-calls, avoid-call-value
(bool success, ) = recipient.call{ value: amount }("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain`call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.call{ value: value }(data);
return _verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
require(isContract(target), "Address: static call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.staticcall(data);
return _verifyCallResult(success, returndata, errorMessage);
}
function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
// solhint-disable-next-line no-inline-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "../proxy/Initializable.sol";
/*
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with GSN meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract ContextUpgradeable is Initializable {
function __Context_init() internal initializer {
__Context_init_unchained();
}
function __Context_init_unchained() internal initializer {
}
function _msgSender() internal view virtual returns (address payable) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes memory) {
this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
return msg.data;
}
uint256[50] private __gap;
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
import "../utils/Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract Ownable is Context {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor () internal {
address msgSender = _msgSender();
_owner = msgSender;
emit OwnershipTransferred(address(0), msgSender);
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
emit OwnershipTransferred(_owner, address(0));
_owner = address(0);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
require(newOwner != address(0), "Ownable: new owner is the zero address");
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
* @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
*
* These functions can be used to verify that a message was signed by the holder
* of the private keys of a given address.
*/
library ECDSA {
/**
* @dev Returns the address that signed a hashed message (`hash`) with
* `signature`. This address can then be used for verification purposes.
*
* The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
* this function rejects them by requiring the `s` value to be in the lower
* half order, and the `v` value to be either 27 or 28.
*
* IMPORTANT: `hash` _must_ be the result of a hash operation for the
* verification to be secure: it is possible to craft signatures that
* recover to arbitrary addresses for non-hashed data. A safe way to ensure
* this is by receiving a hash of the original message (which may otherwise
* be too long), and then calling {toEthSignedMessageHash} on it.
*/
function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
// Check the signature length
if (signature.length != 65) {
revert("ECDSA: invalid signature length");
}
// Divide the signature in r, s and v variables
bytes32 r;
bytes32 s;
uint8 v;
// ecrecover takes the signature parameters, and the only way to get them
// currently is to use assembly.
// solhint-disable-next-line no-inline-assembly
assembly {
r := mload(add(signature, 0x20))
s := mload(add(signature, 0x40))
v := byte(0, mload(add(signature, 0x60)))
}
return recover(hash, v, r, s);
}
/**
* @dev Overload of {ECDSA-recover-bytes32-bytes-} that receives the `v`,
* `r` and `s` signature fields separately.
*/
function recover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal pure returns (address) {
// EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
// unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
// the valid range for s in (281): 0 < s < secp256k1n ÷ 2 + 1, and for v in (282): v ∈ {27, 28}. Most
// signatures from current libraries generate a unique signature with an s-value in the lower half order.
//
// If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
// with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
// vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
// these malleable signatures as well.
require(uint256(s) <= 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0, "ECDSA: invalid signature 's' value");
require(v == 27 || v == 28, "ECDSA: invalid signature 'v' value");
// If the signature is valid (and not malleable), return the signer address
address signer = ecrecover(hash, v, r, s);
require(signer != address(0), "ECDSA: invalid signature");
return signer;
}
/**
* @dev Returns an Ethereum Signed Message, created from a `hash`. This
* replicates the behavior of the
* https://github.com/ethereum/wiki/wiki/JSON-RPC#eth_sign[`eth_sign`]
* JSON-RPC method.
*
* See {recover}.
*/
function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
// 32 is the length in bytes of hash,
// enforced by the type signature above
return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*/
library SafeMath {
/**
* @dev Returns the addition of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
uint256 c = a + b;
if (c < a) return (false, 0);
return (true, c);
}
/**
* @dev Returns the substraction of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
if (b > a) return (false, 0);
return (true, a - b);
}
/**
* @dev Returns the multiplication of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
if (a == 0) return (true, 0);
uint256 c = a * b;
if (c / a != b) return (false, 0);
return (true, c);
}
/**
* @dev Returns the division of two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/
function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
if (b == 0) return (false, 0);
return (true, a / b);
}
/**
* @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/
function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
if (b == 0) return (false, 0);
return (true, a % b);
}
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
*
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a, "SafeMath: subtraction overflow");
return a - b;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
*
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
if (a == 0) return 0;
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers, reverting on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
require(b > 0, "SafeMath: division by zero");
return a / b;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
require(b > 0, "SafeMath: modulo by zero");
return a % b;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on
* overflow (when the result is negative).
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {trySub}.
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b <= a, errorMessage);
return a - b;
}
/**
* @dev Returns the integer division of two unsigned integers, reverting with custom message on
* division by zero. The result is rounded towards zero.
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {tryDiv}.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b > 0, errorMessage);
return a / b;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting with custom message when dividing by zero.
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {tryMod}.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b > 0, errorMessage);
return a % b;
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address recipient, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `sender` to `recipient` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.2 <0.8.0;
/**
* @dev Collection of functions related to the address type
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.
uint256 size;
// solhint-disable-next-line no-inline-assembly
assembly { size := extcodesize(account) }
return size > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
// solhint-disable-next-line avoid-low-level-calls, avoid-call-value
(bool success, ) = recipient.call{ value: amount }("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain`call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.call{ value: value }(data);
return _verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
require(isContract(target), "Address: static call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.staticcall(data);
return _verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
require(isContract(target), "Address: delegate call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.delegatecall(data);
return _verifyCallResult(success, returndata, errorMessage);
}
function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
// solhint-disable-next-line no-inline-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/*
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with GSN meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address payable) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes memory) {
this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
return msg.data;
}
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.5.10;
/*
The MIT License (MIT)
Copyright (c) 2016 Smart Contract Solutions, Inc.
Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:
The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
/**
* @title SafeMath
* @dev Math operations with safety checks that throw on error
*/
library SafeMath {
/**
* @dev Multiplies two numbers, throws on overflow.
*/
function mul(uint256 _a, uint256 _b) internal pure returns (uint256 c) {
// Gas optimization: this is cheaper than asserting 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
if (_a == 0) {
return 0;
}
c = _a * _b;
require(c / _a == _b, "Overflow during multiplication.");
return c;
}
/**
* @dev Integer division of two numbers, truncating the quotient.
*/
function div(uint256 _a, uint256 _b) internal pure returns (uint256) {
// assert(_b > 0); // Solidity automatically throws when dividing by 0
// uint256 c = _a / _b;
// assert(_a == _b * c + _a % _b); // There is no case in which this doesn't hold
return _a / _b;
}
/**
* @dev Subtracts two numbers, throws on overflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 _a, uint256 _b) internal pure returns (uint256) {
require(_b <= _a, "Underflow during subtraction.");
return _a - _b;
}
/**
* @dev Adds two numbers, throws on overflow.
*/
function add(uint256 _a, uint256 _b) internal pure returns (uint256 c) {
c = _a + _b;
require(c >= _a, "Overflow during addition.");
return c;
}
}
// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity >=0.5.10 <0.8.0;
import {SafeMath} from "./SafeMath.sol";
library TypedMemView {
using SafeMath for uint256;
// Why does this exist?
// the solidity `bytes memory` type has a few weaknesses.
// 1. You can't index ranges effectively
// 2. You can't slice without copying
// 3. The underlying data may represent any type
// 4. Solidity never deallocates memory, and memory costs grow
// superlinearly
// By using a memory view instead of a `bytes memory` we get the following
// advantages:
// 1. Slices are done on the stack, by manipulating the pointer
// 2. We can index arbitrary ranges and quickly convert them to stack types
// 3. We can insert type info into the pointer, and typecheck at runtime
// This makes `TypedMemView` a useful tool for efficient zero-copy
// algorithms.
// Why bytes29?
// We want to avoid confusion between views, digests, and other common
// types so we chose a large and uncommonly used odd number of bytes
//
// Note that while bytes are left-aligned in a word, integers and addresses
// are right-aligned. This means when working in assembly we have to
// account for the 3 unused bytes on the righthand side
//
// First 5 bytes are a type flag.
// - ff_ffff_fffe is reserved for unknown type.
// - ff_ffff_ffff is reserved for invalid types/errors.
// next 12 are memory address
// next 12 are len
// bottom 3 bytes are empty
// Assumptions:
// - non-modification of memory.
// - No Solidity updates
// - - wrt free mem point
// - - wrt bytes representation in memory
// - - wrt memory addressing in general
// Usage:
// - create type constants
// - use `assertType` for runtime type assertions
// - - unfortunately we can't do this at compile time yet :(
// - recommended: implement modifiers that perform type checking
// - - e.g.
// - - `uint40 constant MY_TYPE = 3;`
// - - ` modifer onlyMyType(bytes29 myView) { myView.assertType(MY_TYPE); }`
// - instantiate a typed view from a bytearray using `ref`
// - use `index` to inspect the contents of the view
// - use `slice` to create smaller views into the same memory
// - - `slice` can increase the offset
// - - `slice can decrease the length`
// - - must specify the output type of `slice`
// - - `slice` will return a null view if you try to overrun
// - - make sure to explicitly check for this with `notNull` or `assertType`
// - use `equal` for typed comparisons.
// The null view
bytes29 public constant NULL = hex"ffffffffffffffffffffffffffffffffffffffffffffffffffffffffff";
uint256 constant LOW_12_MASK = 0xffffffffffffffffffffffff;
uint8 constant TWELVE_BYTES = 96;
/**
* @notice Returns the encoded hex character that represents the lower 4 bits of the argument.
* @param _b The byte
* @return char - The encoded hex character
*/
function nibbleHex(uint8 _b) internal pure returns (uint8 char) {
// This can probably be done more efficiently, but it's only in error
// paths, so we don't really care :)
uint8 _nibble = _b | 0xf0; // set top 4, keep bottom 4
if (_nibble == 0xf0) {return 0x30;} // 0
if (_nibble == 0xf1) {return 0x31;} // 1
if (_nibble == 0xf2) {return 0x32;} // 2
if (_nibble == 0xf3) {return 0x33;} // 3
if (_nibble == 0xf4) {return 0x34;} // 4
if (_nibble == 0xf5) {return 0x35;} // 5
if (_nibble == 0xf6) {return 0x36;} // 6
if (_nibble == 0xf7) {return 0x37;} // 7
if (_nibble == 0xf8) {return 0x38;} // 8
if (_nibble == 0xf9) {return 0x39;} // 9
if (_nibble == 0xfa) {return 0x61;} // a
if (_nibble == 0xfb) {return 0x62;} // b
if (_nibble == 0xfc) {return 0x63;} // c
if (_nibble == 0xfd) {return 0x64;} // d
if (_nibble == 0xfe) {return 0x65;} // e
if (_nibble == 0xff) {return 0x66;} // f
}
/**
* @notice Returns a uint16 containing the hex-encoded byte.
* @param _b The byte
* @return encoded - The hex-encoded byte
*/
function byteHex(uint8 _b) internal pure returns (uint16 encoded) {
encoded |= nibbleHex(_b >> 4); // top 4 bits
encoded <<= 8;
encoded |= nibbleHex(_b); // lower 4 bits
}
/**
* @notice Encodes the uint256 to hex. `first` contains the encoded top 16 bytes.
* `second` contains the encoded lower 16 bytes.
*
* @param _b The 32 bytes as uint256
* @return first - The top 16 bytes
* @return second - The bottom 16 bytes
*/
function encodeHex(uint256 _b) internal pure returns (uint256 first, uint256 second) {
for (uint8 i = 31; i > 15; i -= 1) {
uint8 _byte = uint8(_b >> (i * 8));
first |= byteHex(_byte);
if (i != 16) {
first <<= 16;
}
}
// abusing underflow here =_=
for (uint8 i = 15; i < 255 ; i -= 1) {
uint8 _byte = uint8(_b >> (i * 8));
second |= byteHex(_byte);
if (i != 0) {
second <<= 16;
}
}
}
/**
* @notice Changes the endianness of a uint256.
* @dev https://graphics.stanford.edu/~seander/bithacks.html#ReverseParallel
* @param _b The unsigned integer to reverse
* @return v - The reversed value
*/
function reverseUint256(uint256 _b) internal pure returns (uint256 v) {
v = _b;
// swap bytes
v = ((v >> 8) & 0x00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF) |
((v & 0x00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF00FF) << 8);
// swap 2-byte long pairs
v = ((v >> 16) & 0x0000FFFF0000FFFF0000FFFF0000FFFF0000FFFF0000FFFF0000FFFF0000FFFF) |
((v & 0x0000FFFF0000FFFF0000FFFF0000FFFF0000FFFF0000FFFF0000FFFF0000FFFF) << 16);
// swap 4-byte long pairs
v = ((v >> 32) & 0x00000000FFFFFFFF00000000FFFFFFFF00000000FFFFFFFF00000000FFFFFFFF) |
((v & 0x00000000FFFFFFFF00000000FFFFFFFF00000000FFFFFFFF00000000FFFFFFFF) << 32);
// swap 8-byte long pairs
v = ((v >> 64) & 0x0000000000000000FFFFFFFFFFFFFFFF0000000000000000FFFFFFFFFFFFFFFF) |
((v & 0x0000000000000000FFFFFFFFFFFFFFFF0000000000000000FFFFFFFFFFFFFFFF) << 64);
// swap 16-byte long pairs
v = (v >> 128) | (v << 128);
}
/**
* @notice Create a mask with the highest `_len` bits set.
* @param _len The length
* @return mask - The mask
*/
function leftMask(uint8 _len) private pure returns (uint256 mask) {
// ugly. redo without assembly?
assembly {
// solium-disable-previous-line security/no-inline-assembly
mask := sar(
sub(_len, 1),
0x8000000000000000000000000000000000000000000000000000000000000000
)
}
}
/**
* @notice Return the null view.
* @return bytes29 - The null view
*/
function nullView() internal pure returns (bytes29) {
return NULL;
}
/**
* @notice Check if the view is null.
* @return bool - True if the view is null
*/
function isNull(bytes29 memView) internal pure returns (bool) {
return memView == NULL;
}
/**
* @notice Check if the view is not null.
* @return bool - True if the view is not null
*/
function notNull(bytes29 memView) internal pure returns (bool) {
return !isNull(memView);
}
/**
* @notice Check if the view is of a valid type and points to a valid location
* in memory.
* @dev We perform this check by examining solidity's unallocated memory
* pointer and ensuring that the view's upper bound is less than that.
* @param memView The view
* @return ret - True if the view is valid
*/
function isValid(bytes29 memView) internal pure returns (bool ret) {
if (typeOf(memView) == 0xffffffffff) {return false;}
uint256 _end = end(memView);
assembly {
// solium-disable-previous-line security/no-inline-assembly
ret := not(gt(_end, mload(0x40)))
}
}
/**
* @notice Require that a typed memory view be valid.
* @dev Returns the view for easy chaining.
* @param memView The view
* @return bytes29 - The validated view
*/
function assertValid(bytes29 memView) internal pure returns (bytes29) {
require(isValid(memView), "Validity assertion failed");
return memView;
}
/**
* @notice Return true if the memview is of the expected type. Otherwise false.
* @param memView The view
* @param _expected The expected type
* @return bool - True if the memview is of the expected type
*/
function isType(bytes29 memView, uint40 _expected) internal pure returns (bool) {
return typeOf(memView) == _expected;
}
/**
* @notice Require that a typed memory view has a specific type.
* @dev Returns the view for easy chaining.
* @param memView The view
* @param _expected The expected type
* @return bytes29 - The view with validated type
*/
function assertType(bytes29 memView, uint40 _expected) internal pure returns (bytes29) {
if (!isType(memView, _expected)) {
(, uint256 g) = encodeHex(uint256(typeOf(memView)));
(, uint256 e) = encodeHex(uint256(_expected));
string memory err = string(
abi.encodePacked(
"Type assertion failed. Got 0x",
uint80(g),
". Expected 0x",
uint80(e)
)
);
revert(err);
}
return memView;
}
/**
* @notice Return an identical view with a different type.
* @param memView The view
* @param _newType The new type
* @return newView - The new view with the specified type
*/
function castTo(bytes29 memView, uint40 _newType) internal pure returns (bytes29 newView) {
// then | in the new type
assembly {
// solium-disable-previous-line security/no-inline-assembly
// shift off the top 5 bytes
newView := or(newView, shr(40, shl(40, memView)))
newView := or(newView, shl(216, _newType))
}
}
/**
* @notice Unsafe raw pointer construction. This should generally not be called
* directly. Prefer `ref` wherever possible.
* @dev Unsafe raw pointer construction. This should generally not be called
* directly. Prefer `ref` wherever possible.
* @param _type The type
* @param _loc The memory address
* @param _len The length
* @return newView - The new view with the specified type, location and length
*/
function unsafeBuildUnchecked(uint256 _type, uint256 _loc, uint256 _len) private pure returns (bytes29 newView) {
assembly {
// solium-disable-previous-line security/no-inline-assembly
newView := shl(96, or(newView, _type)) // insert type
newView := shl(96, or(newView, _loc)) // insert loc
newView := shl(24, or(newView, _len)) // empty bottom 3 bytes
}
}
/**
* @notice Instantiate a new memory view. This should generally not be called
* directly. Prefer `ref` wherever possible.
* @dev Instantiate a new memory view. This should generally not be called
* directly. Prefer `ref` wherever possible.
* @param _type The type
* @param _loc The memory address
* @param _len The length
* @return newView - The new view with the specified type, location and length
*/
function build(uint256 _type, uint256 _loc, uint256 _len) internal pure returns (bytes29 newView) {
uint256 _end = _loc.add(_len);
assembly {
// solium-disable-previous-line security/no-inline-assembly
if gt(_end, mload(0x40)) {
_end := 0
}
}
if (_end == 0) {
return NULL;
}
newView = unsafeBuildUnchecked(_type, _loc, _len);
}
/**
* @notice Instantiate a memory view from a byte array.
* @dev Note that due to Solidity memory representation, it is not possible to
* implement a deref, as the `bytes` type stores its len in memory.
* @param arr The byte array
* @param newType The type
* @return bytes29 - The memory view
*/
function ref(bytes memory arr, uint40 newType) internal pure returns (bytes29) {
uint256 _len = arr.length;
uint256 _loc;
assembly {
// solium-disable-previous-line security/no-inline-assembly
_loc := add(arr, 0x20) // our view is of the data, not the struct
}
return build(newType, _loc, _len);
}
/**
* @notice Return the associated type information.
* @param memView The memory view
* @return _type - The type associated with the view
*/
function typeOf(bytes29 memView) internal pure returns (uint40 _type) {
assembly {
// solium-disable-previous-line security/no-inline-assembly
// 216 == 256 - 40
_type := shr(216, memView) // shift out lower 24 bytes
}
}
/**
* @notice Optimized type comparison. Checks that the 5-byte type flag is equal.
* @param left The first view
* @param right The second view
* @return bool - True if the 5-byte type flag is equal
*/
function sameType(bytes29 left, bytes29 right) internal pure returns (bool) {
return (left ^ right) >> (2 * TWELVE_BYTES) == 0;
}
/**
* @notice Return the memory address of the underlying bytes.
* @param memView The view
* @return _loc - The memory address
*/
function loc(bytes29 memView) internal pure returns (uint96 _loc) {
uint256 _mask = LOW_12_MASK; // assembly can't use globals
assembly {
// solium-disable-previous-line security/no-inline-assembly
// 120 bits = 12 bytes (the encoded loc) + 3 bytes (empty low space)
_loc := and(shr(120, memView), _mask)
}
}
/**
* @notice The number of memory words this memory view occupies, rounded up.
* @param memView The view
* @return uint256 - The number of memory words
*/
function words(bytes29 memView) internal pure returns (uint256) {
return uint256(len(memView)).add(32) / 32;
}
/**
* @notice The in-memory footprint of a fresh copy of the view.
* @param memView The view
* @return uint256 - The in-memory footprint of a fresh copy of the view.
*/
function footprint(bytes29 memView) internal pure returns (uint256) {
return words(memView) * 32;
}
/**
* @notice The number of bytes of the view.
* @param memView The view
* @return _len - The length of the view
*/
function len(bytes29 memView) internal pure returns (uint96 _len) {
uint256 _mask = LOW_12_MASK; // assembly can't use globals
assembly {
// solium-disable-previous-line security/no-inline-assembly
_len := and(shr(24, memView), _mask)
}
}
/**
* @notice Returns the endpoint of `memView`.
* @param memView The view
* @return uint256 - The endpoint of `memView`
*/
function end(bytes29 memView) internal pure returns (uint256) {
return loc(memView) + len(memView);
}
/**
* @notice Safe slicing without memory modification.
* @param memView The view
* @param _index The start index
* @param _len The length
* @param newType The new type
* @return bytes29 - The new view
*/
function slice(bytes29 memView, uint256 _index, uint256 _len, uint40 newType) internal pure returns (bytes29) {
uint256 _loc = loc(memView);
// Ensure it doesn't overrun the view
if (_loc.add(_index).add(_len) > end(memView)) {
return NULL;
}
_loc = _loc.add(_index);
return build(newType, _loc, _len);
}
/**
* @notice Shortcut to `slice`. Gets a view representing the first `_len` bytes.
* @param memView The view
* @param _len The length
* @param newType The new type
* @return bytes29 - The new view
*/
function prefix(bytes29 memView, uint256 _len, uint40 newType) internal pure returns (bytes29) {
return slice(memView, 0, _len, newType);
}
/**
* @notice Shortcut to `slice`. Gets a view representing the last `_len` byte.
* @param memView The view
* @param _len The length
* @param newType The new type
* @return bytes29 - The new view
*/
function postfix(bytes29 memView, uint256 _len, uint40 newType) internal pure returns (bytes29) {
return slice(memView, uint256(len(memView)).sub(_len), _len, newType);
}
/**
* @notice Construct an error message for an indexing overrun.
* @param _loc The memory address
* @param _len The length
* @param _index The index
* @param _slice The slice where the overrun occurred
* @return err - The err
*/
function indexErrOverrun(
uint256 _loc,
uint256 _len,
uint256 _index,
uint256 _slice
) internal pure returns (string memory err) {
(, uint256 a) = encodeHex(_loc);
(, uint256 b) = encodeHex(_len);
(, uint256 c) = encodeHex(_index);
(, uint256 d) = encodeHex(_slice);
err = string(
abi.encodePacked(
"TypedMemView/index - Overran the view. Slice is at 0x",
uint48(a),
" with length 0x",
uint48(b),
". Attempted to index at offset 0x",
uint48(c),
" with length 0x",
uint48(d),
"."
)
);
}
/**
* @notice Load up to 32 bytes from the view onto the stack.
* @dev Returns a bytes32 with only the `_bytes` highest bytes set.
* This can be immediately cast to a smaller fixed-length byte array.
* To automatically cast to an integer, use `indexUint`.
* @param memView The view
* @param _index The index
* @param _bytes The bytes
* @return result - The 32 byte result
*/
function index(bytes29 memView, uint256 _index, uint8 _bytes) internal pure returns (bytes32 result) {
if (_bytes == 0) {return bytes32(0);}
if (_index.add(_bytes) > len(memView)) {
revert(indexErrOverrun(loc(memView), len(memView), _index, uint256(_bytes)));
}
require(_bytes <= 32, "TypedMemView/index - Attempted to index more than 32 bytes");
uint8 bitLength = _bytes * 8;
uint256 _loc = loc(memView);
uint256 _mask = leftMask(bitLength);
assembly {
// solium-disable-previous-line security/no-inline-assembly
result := and(mload(add(_loc, _index)), _mask)
}
}
/**
* @notice Parse an unsigned integer from the view at `_index`.
* @dev Requires that the view have >= `_bytes` bytes following that index.
* @param memView The view
* @param _index The index
* @param _bytes The bytes
* @return result - The unsigned integer
*/
function indexUint(bytes29 memView, uint256 _index, uint8 _bytes) internal pure returns (uint256 result) {
return uint256(index(memView, _index, _bytes)) >> ((32 - _bytes) * 8);
}
/**
* @notice Parse an unsigned integer from LE bytes.
* @param memView The view
* @param _index The index
* @param _bytes The bytes
* @return result - The unsigned integer
*/
function indexLEUint(bytes29 memView, uint256 _index, uint8 _bytes) internal pure returns (uint256 result) {
return reverseUint256(uint256(index(memView, _index, _bytes)));
}
/**
* @notice Parse an address from the view at `_index`. Requires that the view have >= 20 bytes
* following that index.
* @param memView The view
* @param _index The index
* @return address - The address
*/
function indexAddress(bytes29 memView, uint256 _index) internal pure returns (address) {
return address(uint160(indexUint(memView, _index, 20)));
}
/**
* @notice Return the keccak256 hash of the underlying memory
* @param memView The view
* @return digest - The keccak256 hash of the underlying memory
*/
function keccak(bytes29 memView) internal pure returns (bytes32 digest) {
uint256 _loc = loc(memView);
uint256 _len = len(memView);
assembly {
// solium-disable-previous-line security/no-inline-assembly
digest := keccak256(_loc, _len)
}
}
/**
* @notice Return the sha2 digest of the underlying memory.
* @dev We explicitly deallocate memory afterwards.
* @param memView The view
* @return digest - The sha2 hash of the underlying memory
*/
function sha2(bytes29 memView) internal view returns (bytes32 digest) {
uint256 _loc = loc(memView);
uint256 _len = len(memView);
assembly {
// solium-disable-previous-line security/no-inline-assembly
let ptr := mload(0x40)
pop(staticcall(gas(), 2, _loc, _len, ptr, 0x20)) // sha2 #1
digest := mload(ptr)
}
}
/**
* @notice Implements bitcoin's hash160 (rmd160(sha2()))
* @param memView The pre-image
* @return digest - the Digest
*/
function hash160(bytes29 memView) internal view returns (bytes20 digest) {
uint256 _loc = loc(memView);
uint256 _len = len(memView);
assembly {
// solium-disable-previous-line security/no-inline-assembly
let ptr := mload(0x40)
pop(staticcall(gas(), 2, _loc, _len, ptr, 0x20)) // sha2
pop(staticcall(gas(), 3, ptr, 0x20, ptr, 0x20)) // rmd160
digest := mload(add(ptr, 0xc)) // return value is 0-prefixed.
}
}
/**
* @notice Implements bitcoin's hash256 (double sha2)
* @param memView A view of the preimage
* @return digest - the Digest
*/
function hash256(bytes29 memView) internal view returns (bytes32 digest) {
uint256 _loc = loc(memView);
uint256 _len = len(memView);
assembly {
// solium-disable-previous-line security/no-inline-assembly
let ptr := mload(0x40)
pop(staticcall(gas(), 2, _loc, _len, ptr, 0x20)) // sha2 #1
pop(staticcall(gas(), 2, ptr, 0x20, ptr, 0x20)) // sha2 #2
digest := mload(ptr)
}
}
/**
* @notice Return true if the underlying memory is equal. Else false.
* @param left The first view
* @param right The second view
* @return bool - True if the underlying memory is equal
*/
function untypedEqual(bytes29 left, bytes29 right) internal pure returns (bool) {
return (loc(left) == loc(right) && len(left) == len(right)) || keccak(left) == keccak(right);
}
/**
* @notice Return false if the underlying memory is equal. Else true.
* @param left The first view
* @param right The second view
* @return bool - False if the underlying memory is equal
*/
function untypedNotEqual(bytes29 left, bytes29 right) internal pure returns (bool) {
return !untypedEqual(left, right);
}
/**
* @notice Compares type equality.
* @dev Shortcuts if the pointers are identical, otherwise compares type and digest.
* @param left The first view
* @param right The second view
* @return bool - True if the types are the same
*/
function equal(bytes29 left, bytes29 right) internal pure returns (bool) {
return left == right || (typeOf(left) == typeOf(right) && keccak(left) == keccak(right));
}
/**
* @notice Compares type inequality.
* @dev Shortcuts if the pointers are identical, otherwise compares type and digest.
* @param left The first view
* @param right The second view
* @return bool - True if the types are not the same
*/
function notEqual(bytes29 left, bytes29 right) internal pure returns (bool) {
return !equal(left, right);
}
/**
* @notice Copy the view to a location, return an unsafe memory reference
* @dev Super Dangerous direct memory access.
*
* This reference can be overwritten if anything else modifies memory (!!!).
* As such it MUST be consumed IMMEDIATELY.
* This function is private to prevent unsafe usage by callers.
* @param memView The view
* @param _newLoc The new location
* @return written - the unsafe memory reference
*/
function unsafeCopyTo(bytes29 memView, uint256 _newLoc) private view returns (bytes29 written) {
require(notNull(memView), "TypedMemView/copyTo - Null pointer deref");
require(isValid(memView), "TypedMemView/copyTo - Invalid pointer deref");
uint256 _len = len(memView);
uint256 _oldLoc = loc(memView);
uint256 ptr;
assembly {
// solium-disable-previous-line security/no-inline-assembly
ptr := mload(0x40)
// revert if we're writing in occupied memory
if gt(ptr, _newLoc) {
revert(0x60, 0x20) // empty revert message
}
// use the identity precompile to copy
// guaranteed not to fail, so pop the success
pop(staticcall(gas(), 4, _oldLoc, _len, _newLoc, _len))
}
written = unsafeBuildUnchecked(typeOf(memView), _newLoc, _len);
}
/**
* @notice Copies the referenced memory to a new loc in memory, returning a `bytes` pointing to
* the new memory
* @dev Shortcuts if the pointers are identical, otherwise compares type and digest.
* @param memView The view
* @return ret - The view pointing to the new memory
*/
function clone(bytes29 memView) internal view returns (bytes memory ret) {
uint256 ptr;
uint256 _len = len(memView);
assembly {
// solium-disable-previous-line security/no-inline-assembly
ptr := mload(0x40) // load unused memory pointer
ret := ptr
}
unsafeCopyTo(memView, ptr + 0x20);
assembly {
// solium-disable-previous-line security/no-inline-assembly
mstore(0x40, add(add(ptr, _len), 0x20)) // write new unused pointer
mstore(ptr, _len) // write len of new array (in bytes)
}
}
/**
* @notice Join the views in memory, return an unsafe reference to the memory.
* @dev Super Dangerous direct memory access.
*
* This reference can be overwritten if anything else modifies memory (!!!).
* As such it MUST be consumed IMMEDIATELY.
* This function is private to prevent unsafe usage by callers.
* @param memViews The views
* @return unsafeView - The conjoined view pointing to the new memory
*/
function unsafeJoin(bytes29[] memory memViews, uint256 _location) private view returns (bytes29 unsafeView) {
assembly {
// solium-disable-previous-line security/no-inline-assembly
let ptr := mload(0x40)
// revert if we're writing in occupied memory
if gt(ptr, _location) {
revert(0x60, 0x20) // empty revert message
}
}
uint256 _offset = 0;
for (uint256 i = 0; i < memViews.length; i ++) {
bytes29 memView = memViews[i];
unsafeCopyTo(memView, _location + _offset);
_offset += len(memView);
}
unsafeView = unsafeBuildUnchecked(0, _location, _offset);
}
/**
* @notice Produce the keccak256 digest of the concatenated contents of multiple views.
* @param memViews The views
* @return bytes32 - The keccak256 digest
*/
function joinKeccak(bytes29[] memory memViews) internal view returns (bytes32) {
uint256 ptr;
assembly {
// solium-disable-previous-line security/no-inline-assembly
ptr := mload(0x40) // load unused memory pointer
}
return keccak(unsafeJoin(memViews, ptr));
}
/**
* @notice Produce the sha256 digest of the concatenated contents of multiple views.
* @param memViews The views
* @return bytes32 - The sha256 digest
*/
function joinSha2(bytes29[] memory memViews) internal view returns (bytes32) {
uint256 ptr;
assembly {
// solium-disable-previous-line security/no-inline-assembly
ptr := mload(0x40) // load unused memory pointer
}
return sha2(unsafeJoin(memViews, ptr));
}
/**
* @notice copies all views, joins them into a new bytearray.
* @param memViews The views
* @return ret - The new byte array
*/
function join(bytes29[] memory memViews) internal view returns (bytes memory ret) {
uint256 ptr;
assembly {
// solium-disable-previous-line security/no-inline-assembly
ptr := mload(0x40) // load unused memory pointer
}
bytes29 _newView = unsafeJoin(memViews, ptr + 0x20);
uint256 _written = len(_newView);
uint256 _footprint = footprint(_newView);
assembly {
// solium-disable-previous-line security/no-inline-assembly
// store the legnth
mstore(ptr, _written)
// new pointer is old + 0x20 + the footprint of the body
mstore(0x40, add(add(ptr, _footprint), 0x20))
ret := ptr
}
}
}
// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity 0.7.6;
// ============ External Imports ============
import {TypedMemView} from "@summa-tx/memview-sol/contracts/TypedMemView.sol";
library BridgeMessage {
// ============ Libraries ============
using TypedMemView for bytes;
using TypedMemView for bytes29;
// ============ Enums ============
// WARNING: do NOT re-write the numbers / order
// of message types in an upgrade;
// will cause in-flight messages to be mis-interpreted
// The Types enum has to do with the TypedMemView library and it defines
// the types of `views` that we use in BridgeMessage. A view is not interesting data
// itself, but rather it points to a specific part of the memory where
// the data we care about live. When we give a `type` to a view, we define what type
// is the data it points to, so that we can do easy runtime assertions without
// having to fetch the whole data from memory and check for ourselves. In BridgeMessage.sol
// the types of `data` we can have are defined in this enum and may belong to different taxonomies.
// For example, a `Message` includes a `TokenId` and an Action, either a `Transfer` or a `TransferToHook`.
// The Message is a different TYPE of data than a TokenId or Transfer, as TokenId and Transfer live inside
// the message. For that reason, we define them as different data types and we add them to the same enum
// for ease of use.
enum Types {
Invalid, // 0
TokenId, // 1
Message, // 2
Transfer, // 3
DeprecatedFastTransfer, // 4
TransferToHook, // 5
ExtraData // 6
}
// ============ Structs ============
// Tokens are identified by a TokenId:
// domain - 4 byte chain ID of the chain from which the token originates
// id - 32 byte identifier of the token address on the origin chain, in that chain's address format
struct TokenId {
uint32 domain;
bytes32 id;
}
// ============ Constants ============
uint256 private constant TOKEN_ID_LEN = 36; // 4 bytes domain + 32 bytes id
uint256 private constant IDENTIFIER_LEN = 1;
uint256 private constant TRANSFER_LEN = 97; // 1 byte identifier + 32 bytes recipient + 32 bytes amount + 32 bytes detailsHash
uint256 private constant MIN_TRANSFER_HOOK_LEN = 129; // 1 byte identifier + 32 bytes hook address + 32 bytes amount + 32 bytes detailsHash + 32 bytes sender + X bytes extraData
// ============ Modifiers ============
/**
* @notice Asserts a message is of type `_t`
* @param _view The message
* @param _t The expected type
*/
modifier typeAssert(bytes29 _view, Types _t) {
_view.assertType(uint40(_t));
_;
}
// ============ Internal Functions ============
/**
* @notice Checks that Action is valid type
* @param _action The action
* @return TRUE if action is valid
*/
function isValidAction(bytes29 _action) internal pure returns (bool) {
return isTransfer(_action) || isTransferToHook(_action);
}
/**
* @notice Checks that view is a valid message length
* @param _view The bytes string
* @return TRUE if message is valid
*/
function isValidMessageLength(bytes29 _view) internal pure returns (bool) {
uint256 _len = _view.len();
return
_len == TOKEN_ID_LEN + TRANSFER_LEN ||
_len >= TOKEN_ID_LEN + MIN_TRANSFER_HOOK_LEN;
}
/**
* @notice Formats an action message
* @param _tokenId The token ID
* @param _action The action
* @return The formatted message
*/
function formatMessage(bytes29 _tokenId, bytes29 _action)
internal
view
typeAssert(_tokenId, Types.TokenId)
returns (bytes memory)
{
require(isValidAction(_action), "!action");
bytes29[] memory _views = new bytes29[](2);
_views[0] = _tokenId;
_views[1] = _action;
return TypedMemView.join(_views);
}
/**
* @notice Returns the type of the message
* @param _view The message
* @return The type of the message
*/
function messageType(bytes29 _view) internal pure returns (Types) {
return Types(uint8(_view.typeOf()));
}
/**
* @notice Checks that the message is of the specified type
* @param _type the type to check for
* @param _action The message
* @return True if the message is of the specified type
*/
function isType(bytes29 _action, Types _type) internal pure returns (bool) {
return
actionType(_action) == uint8(_type) &&
messageType(_action) == _type;
}
/**
* @notice Checks that the message is of type Transfer
* @param _action The message
* @return True if the message is of type Transfer
*/
function isTransfer(bytes29 _action) internal pure returns (bool) {
return isType(_action, Types.Transfer);
}
/**
* @notice Checks that the message is of type TransferToHook
* @param _action The message
* @return True if the message is of type TransferToHook
*/
function isTransferToHook(bytes29 _action) internal pure returns (bool) {
return isType(_action, Types.TransferToHook);
}
/**
* @notice Formats Transfer
* @param _to The recipient address as bytes32
* @param _amnt The transfer amount
* @param _detailsHash The hash of the token name, symbol, and decimals
* @return
*/
function formatTransfer(
bytes32 _to,
uint256 _amnt,
bytes32 _detailsHash
) internal pure returns (bytes29) {
return
abi.encodePacked(Types.Transfer, _to, _amnt, _detailsHash).ref(
uint40(Types.Transfer)
);
}
/**
* @notice Formats TransferToHook message
* @param _hook The hook that will handle this token transfer
* @param _amnt The transfer amount
* @param _detailsHash The hash of the token name, symbol, and decimals
* @param _extraData User-provided data for the receiving hook
* @return
*/
function formatTransferToHook(
bytes32 _hook,
uint256 _amnt,
bytes32 _detailsHash,
bytes32 _sender,
bytes memory _extraData
) internal pure returns (bytes29) {
return
abi
.encodePacked(
Types.TransferToHook,
_hook,
_amnt,
_detailsHash,
_sender,
_extraData
)
.ref(uint40(Types.TransferToHook));
}
/**
* @notice Serializes a Token ID struct
* @param _tokenId The token id struct
* @return The formatted Token ID
*/
function formatTokenId(TokenId memory _tokenId)
internal
pure
returns (bytes29)
{
return formatTokenId(_tokenId.domain, _tokenId.id);
}
/**
* @notice Creates a serialized Token ID from components
* @param _domain The domain
* @param _id The ID
* @return The formatted Token ID
*/
function formatTokenId(uint32 _domain, bytes32 _id)
internal
pure
returns (bytes29)
{
return abi.encodePacked(_domain, _id).ref(uint40(Types.TokenId));
}
/**
* @notice Formats the keccak256 hash of the token details
* Token Details Format:
* length of name cast to bytes - 32 bytes
* name - x bytes (variable)
* length of symbol cast to bytes - 32 bytes
* symbol - x bytes (variable)
* decimals - 1 byte
* @param _name The name
* @param _symbol The symbol
* @param _decimals The decimals
* @return The Details message
*/
function getDetailsHash(
string memory _name,
string memory _symbol,
uint8 _decimals
) internal pure returns (bytes32) {
return
keccak256(
abi.encodePacked(
bytes(_name).length,
_name,
bytes(_symbol).length,
_symbol,
_decimals
)
);
}
/**
* @notice Retrieves the domain from a TokenID
* @param _tokenId The message
* @return The domain
*/
function domain(bytes29 _tokenId)
internal
pure
typeAssert(_tokenId, Types.TokenId)
returns (uint32)
{
return uint32(_tokenId.indexUint(0, 4));
}
/**
* @notice Retrieves the ID from a TokenID
* @param _tokenId The message
* @return The ID
*/
function id(bytes29 _tokenId)
internal
pure
typeAssert(_tokenId, Types.TokenId)
returns (bytes32)
{
// before = 4 bytes domain
return _tokenId.index(4, 32);
}
/**
* @notice Retrieves the EVM ID
* @param _tokenId The message
* @return The EVM ID
*/
function evmId(bytes29 _tokenId)
internal
pure
typeAssert(_tokenId, Types.TokenId)
returns (address)
{
// before = 4 bytes domain + 12 bytes empty to trim for address
return _tokenId.indexAddress(16);
}
/**
* @notice Retrieves the action identifier from message
* @param _message The action
* @return The message type
*/
function msgType(bytes29 _message) internal pure returns (uint8) {
return uint8(_message.indexUint(TOKEN_ID_LEN, 1));
}
/**
* @notice Retrieves the identifier from action
* @param _action The action
* @return The action type
*/
function actionType(bytes29 _action) internal pure returns (uint8) {
return uint8(_action.indexUint(0, 1));
}
/**
* @notice Retrieves the recipient from a Transfer
* @param _transferAction The message
* @return The recipient address as bytes32
*/
function recipient(bytes29 _transferAction)
internal
pure
typeAssert(_transferAction, Types.Transfer)
returns (bytes32)
{
// before = 1 byte identifier
return _transferAction.index(1, 32);
}
/**
* @notice Retrieves the EVM Recipient from a Transfer
* @param _transferAction The message
* @return The EVM Recipient
*/
function evmRecipient(bytes29 _transferAction)
internal
pure
typeAssert(_transferAction, Types.Transfer)
returns (address)
{
// before = 1 byte identifier + 12 bytes empty to trim for address = 13 bytes
return _transferAction.indexAddress(13);
}
/**
* @notice Retrieves the amount from a Transfer
* @param _transferAction The message
* @return The amount
*/
function amnt(bytes29 _transferAction) internal pure returns (uint256) {
// before = 1 byte identifier + 32 bytes ID = 33 bytes
return _transferAction.indexUint(33, 32);
}
/**
* @notice Retrieves the detailsHash from a Transfer
* @param _transferAction The message
* @return The detailsHash
*/
function detailsHash(bytes29 _transferAction)
internal
pure
returns (bytes32)
{
// before = 1 byte identifier + 32 bytes ID + 32 bytes amount = 65 bytes
return _transferAction.index(65, 32);
}
/**
* @notice Retrieves the token ID from a Message
* @param _message The message
* @return The ID
*/
function tokenId(bytes29 _message)
internal
pure
typeAssert(_message, Types.Message)
returns (bytes29)
{
return _message.slice(0, TOKEN_ID_LEN, uint40(Types.TokenId));
}
/**
* @notice Retrieves the hook contract EVM address from a TransferWithHook
* @param _transferAction The message
* @return The hook contract address
*/
function evmHook(bytes29 _transferAction)
internal
pure
typeAssert(_transferAction, Types.TransferToHook)
returns (address)
{
return _transferAction.indexAddress(13);
}
/**
* @notice Retrieves the sender from a TransferWithHook
* @param _transferAction The message
* @return The sender as bytes32
*/
function sender(bytes29 _transferAction)
internal
pure
typeAssert(_transferAction, Types.TransferToHook)
returns (bytes32)
{
// before = 1 byte identifier + 32 bytes hook address + 32 bytes amount + 32 bytes detailsHash = 97
return _transferAction.index(97, 32);
}
/**
* @notice Retrieves the extra data from a TransferWithHook
* @param _transferAction The message
* @return A TypedMemview of extraData
*/
function extraData(bytes29 _transferAction)
internal
pure
typeAssert(_transferAction, Types.TransferToHook)
returns (bytes29)
{
// anything past the end is the extradata
return
_transferAction.slice(
MIN_TRANSFER_HOOK_LEN,
_transferAction.len() - MIN_TRANSFER_HOOK_LEN,
uint40(Types.ExtraData)
);
}
/**
* @notice Retrieves the action data from a Message
* @param _message The message
* @return The action
*/
function action(bytes29 _message)
internal
pure
typeAssert(_message, Types.Message)
returns (bytes29)
{
uint256 _actionLen = _message.len() - TOKEN_ID_LEN;
uint40 _type = uint40(msgType(_message));
return _message.slice(TOKEN_ID_LEN, _actionLen, _type);
}
/**
* @notice Converts to a Message
* @param _message The message
* @return The newly typed message
*/
function tryAsMessage(bytes29 _message) internal pure returns (bytes29) {
if (isValidMessageLength(_message)) {
return _message.castTo(uint40(Types.Message));
}
return TypedMemView.nullView();
}
/**
* @notice Asserts that the message is of type Message
* @param _view The message
* @return The message
*/
function mustBeMessage(bytes29 _view) internal pure returns (bytes29) {
return tryAsMessage(_view).assertValid();
}
}
// SPDX-License-Identifier: MIT
pragma solidity 0.7.6;
// This is modified from "@openzeppelin/contracts/token/ERC20/IERC20.sol"
// Modifications were made to make the tokenName, tokenSymbol, and
// tokenDecimals fields internal instead of private. Getters for them were
// removed to silence solidity inheritance issues
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/math/SafeMath.sol";
/**
* @dev Implementation of the {IERC20} interface.
*
* This implementation is agnostic to the way tokens are created. This means
* that a supply mechanism has to be added in a derived contract using {_mint}.
* For a generic mechanism see {ERC20PresetMinterPauser}.
*
* TIP: For a detailed writeup see our guide
* https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
* to implement supply mechanisms].
*
* We have followed general OpenZeppelin guidelines: functions revert instead
* of returning `false` on failure. This behavior is nonetheless conventional
* and does not conflict with the expectations of ERC20 applications.
*
* Additionally, an {Approval} event is emitted on calls to {transferFrom}.
* This allows applications to reconstruct the allowance for all accounts just
* by listening to said events. Other implementations of the EIP may not emit
* these events, as it isn't required by the specification.
*
* Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
* functions have been added to mitigate the well-known issues around setting
* allowances. See {IERC20-approve}.
*/
abstract contract ERC20 is IERC20 {
using SafeMath for uint256;
mapping(address => uint256) private balances;
mapping(address => mapping(address => uint256)) private allowances;
uint256 private supply;
struct Token {
string name;
string symbol;
uint8 decimals;
}
Token internal token;
/**
* @dev See {IERC20-transfer}.
*
* Requirements:
*
* - `_recipient` cannot be the zero address.
* - the caller must have a balance of at least `_amount`.
*/
function transfer(address _recipient, uint256 _amount)
public
virtual
override
returns (bool)
{
_transfer(msg.sender, _recipient, _amount);
return true;
}
/**
* @dev See {IERC20-approve}.
*
* Requirements:
*
* - `_spender` cannot be the zero address.
*/
function approve(address _spender, uint256 _amount)
public
virtual
override
returns (bool)
{
_approve(msg.sender, _spender, _amount);
return true;
}
/**
* @dev See {IERC20-transferFrom}.
*
* Emits an {Approval} event indicating the updated allowance. This is not
* required by the EIP. See the note at the beginning of {ERC20}.
*
* Requirements:
*
* - `_sender` and `recipient` cannot be the zero address.
* - `_sender` must have a balance of at least `amount`.
* - the caller must have allowance for ``_sender``'s tokens of at least
* `amount`.
*/
function transferFrom(
address _sender,
address _recipient,
uint256 _amount
) public virtual override returns (bool) {
_transfer(_sender, _recipient, _amount);
_approve(
_sender,
msg.sender,
allowances[_sender][msg.sender].sub(
_amount,
"ERC20: transfer amount exceeds allowance"
)
);
return true;
}
/**
* @dev Atomically increases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `_spender` cannot be the zero address.
*/
function increaseAllowance(address _spender, uint256 _addedValue)
public
virtual
returns (bool)
{
_approve(
msg.sender,
_spender,
allowances[msg.sender][_spender].add(_addedValue)
);
return true;
}
/**
* @dev Atomically decreases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `_spender` cannot be the zero address.
* - `_spender` must have allowance for the caller of at least
* `_subtractedValue`.
*/
function decreaseAllowance(address _spender, uint256 _subtractedValue)
public
virtual
returns (bool)
{
_approve(
msg.sender,
_spender,
allowances[msg.sender][_spender].sub(
_subtractedValue,
"ERC20: decreased allowance below zero"
)
);
return true;
}
/**
* @dev See {IERC20-totalSupply}.
*/
function totalSupply() public view override returns (uint256) {
return supply;
}
/**
* @dev See {IERC20-balanceOf}.
*/
function balanceOf(address _account)
public
view
virtual
override
returns (uint256)
{
return balances[_account];
}
/**
* @dev See {IERC20-allowance}.
*/
function allowance(address _owner, address _spender)
public
view
virtual
override
returns (uint256)
{
return allowances[_owner][_spender];
}
/**
* @dev Moves tokens `amount` from `_sender` to `_recipient`.
*
* This is internal function is equivalent to {transfer}, and can be used to
* e.g. implement automatic token fees, slashing mechanisms, etc.
*
* Emits a {Transfer} event.
*
* Requirements:
*
* - `_sender` cannot be the zero address.
* - `_recipient` cannot be the zero address.
* - `_sender` must have a balance of at least `amount`.
*/
function _transfer(
address _sender,
address _recipient,
uint256 amount
) internal virtual {
require(_sender != address(0), "ERC20: transfer from the zero address");
require(
_recipient != address(0),
"ERC20: transfer to the zero address"
);
_beforeTokenTransfer(_sender, _recipient, amount);
balances[_sender] = balances[_sender].sub(
amount,
"ERC20: transfer amount exceeds balance"
);
balances[_recipient] = balances[_recipient].add(amount);
emit Transfer(_sender, _recipient, amount);
}
/** @dev Creates `_amount` tokens and assigns them to `_account`, increasing
* the total supply.
*
* Emits a {Transfer} event with `from` set to the zero address.
*
* Requirements:
*
* - `to` cannot be the zero address.
*/
function _mint(address _account, uint256 _amount) internal virtual {
require(_account != address(0), "ERC20: mint to the zero address");
_beforeTokenTransfer(address(0), _account, _amount);
supply = supply.add(_amount);
balances[_account] = balances[_account].add(_amount);
emit Transfer(address(0), _account, _amount);
}
/**
* @dev Destroys `_amount` tokens from `_account`, reducing the
* total supply.
*
* Emits a {Transfer} event with `to` set to the zero address.
*
* Requirements:
*
* - `_account` cannot be the zero address.
* - `_account` must have at least `_amount` tokens.
*/
function _burn(address _account, uint256 _amount) internal virtual {
require(_account != address(0), "ERC20: burn from the zero address");
_beforeTokenTransfer(_account, address(0), _amount);
balances[_account] = balances[_account].sub(
_amount,
"ERC20: burn amount exceeds balance"
);
supply = supply.sub(_amount);
emit Transfer(_account, address(0), _amount);
}
/**
* @dev Sets `_amount` as the allowance of `_spender` over the `_owner` s tokens.
*
* This internal function is equivalent to `approve`, and can be used to
* e.g. set automatic allowances for certain subsystems, etc.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `_owner` cannot be the zero address.
* - `_spender` cannot be the zero address.
*/
function _approve(
address _owner,
address _spender,
uint256 _amount
) internal virtual {
require(_owner != address(0), "ERC20: approve from the zero address");
require(_spender != address(0), "ERC20: approve to the zero address");
allowances[_owner][_spender] = _amount;
emit Approval(_owner, _spender, _amount);
}
/**
* @dev Sets {decimals_} to a value other than the default one of 18.
*
* WARNING: This function should only be called from the constructor. Most
* applications that interact with token contracts will not expect
* {decimals_} to ever change, and may work incorrectly if it does.
*/
function _setupDecimals(uint8 decimals_) internal {
token.decimals = decimals_;
}
/**
* @dev Hook that is called before any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `_from` and `_to` are both non-zero, `_amount` of ``_from``'s tokens
* will be to transferred to `_to`.
* - when `_from` is zero, `_amount` tokens will be minted for `_to`.
* - when `_to` is zero, `_amount` of ``_from``'s tokens will be burned.
* - `_from` and `_to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _beforeTokenTransfer(
address _from,
address _to,
uint256 _amount
) internal virtual {}
}
packages/contracts-core/contracts/Home.sol
// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity 0.7.6;
// ============ Internal Imports ============
import {Version0} from "./Version0.sol";
import {NomadBase} from "./NomadBase.sol";
import {QueueLib} from "./libs/Queue.sol";
import {MerkleLib} from "./libs/Merkle.sol";
import {Message} from "./libs/Message.sol";
import {MerkleTreeManager} from "./Merkle.sol";
import {QueueManager} from "./Queue.sol";
import {IUpdaterManager} from "./interfaces/IUpdaterManager.sol";
// ============ External Imports ============
import {Address} from "@openzeppelin/contracts/utils/Address.sol";
/**
* @title Home
* @author Illusory Systems Inc.
* @notice Accepts messages to be dispatched to remote chains,
* constructs a Merkle tree of the messages,
* and accepts signatures from a bonded Updater
* which notarize the Merkle tree roots.
* Accepts submissions of fraudulent signatures
* by the Updater and slashes the Updater in this case.
*/
contract Home is Version0, QueueManager, MerkleTreeManager, NomadBase {
// ============ Libraries ============
using QueueLib for QueueLib.Queue;
using MerkleLib for MerkleLib.Tree;
// ============ Constants ============
// Maximum bytes per message = 2 KiB
// (somewhat arbitrarily set to begin)
uint256 public constant MAX_MESSAGE_BODY_BYTES = 2 * 2**10;
// ============ Public Storage Variables ============
// domain => next available nonce for the domain
mapping(uint32 => uint32) public nonces;
// contract responsible for Updater bonding, slashing and rotation
IUpdaterManager public updaterManager;
// ============ Upgrade Gap ============
// gap for upgrade safety
uint256[48] private __GAP;
// ============ Events ============
/**
* @notice Emitted when a new message is dispatched via Nomad
* @param messageHash Hash of message; the leaf inserted to the Merkle tree
* for the message
* @param leafIndex Index of message's leaf in merkle tree
* @param destinationAndNonce Destination and destination-specific
* nonce combined in single field ((destination << 32) & nonce)
* @param committedRoot the latest notarized root submitted in the last
* signed Update
* @param message Raw bytes of message
*/
event Dispatch(
bytes32 indexed messageHash,
uint256 indexed leafIndex,
uint64 indexed destinationAndNonce,
bytes32 committedRoot,
bytes message
);
/**
* @notice Emitted when proof of an improper update is submitted,
* which sets the contract to FAILED state
* @param oldRoot Old root of the improper update
* @param newRoot New root of the improper update
* @param signature Signature on `oldRoot` and `newRoot
*/
event ImproperUpdate(bytes32 oldRoot, bytes32 newRoot, bytes signature);
/**
* @notice Emitted when proof of a double update is submitted,
* which sets the contract to FAILED state
* @param oldRoot Old root shared between two conflicting updates
* @param newRoot Array containing two conflicting new roots
* @param signature Signature on `oldRoot` and `newRoot`[0]
* @param signature2 Signature on `oldRoot` and `newRoot`[1]
*/
event DoubleUpdate(
bytes32 oldRoot,
bytes32[2] newRoot,
bytes signature,
bytes signature2
);
/**
* @notice Emitted when the Updater is slashed
* (should be paired with ImproperUpdater or DoubleUpdate event)
* @param updater The address of the updater
* @param reporter The address of the entity that reported the updater misbehavior
*/
event UpdaterSlashed(address indexed updater, address indexed reporter);
/**
* @notice Emitted when the UpdaterManager contract is changed
* @param updaterManager The address of the new updaterManager
*/
event NewUpdaterManager(address updaterManager);
// ============ Constructor ============
constructor(uint32 _localDomain) NomadBase(_localDomain) {} // solhint-disable-line no-empty-blocks
// ============ Initializer ============
function initialize(IUpdaterManager _updaterManager) public initializer {
// initialize queue, set Updater Manager, and initialize
__QueueManager_initialize();
_setUpdaterManager(_updaterManager);
__NomadBase_initialize(updaterManager.updater());
}
// ============ Modifiers ============
/**
* @notice Ensures that function is called by the UpdaterManager contract
*/
modifier onlyUpdaterManager() {
require(msg.sender == address(updaterManager), "!updaterManager");
_;
}
/**
* @notice Ensures that contract state != FAILED when the function is called
*/
modifier notFailed() {
require(state != States.Failed, "failed state");
_;
}
// ============ External: Updater & UpdaterManager Configuration ============
/**
* @notice Set a new Updater
* @dev To be set when rotating Updater after Fraud
* @param _updater the new Updater
*/
function setUpdater(address _updater) external onlyUpdaterManager {
_setUpdater(_updater);
// set the Home state to Active
// now that Updater has been rotated
state = States.Active;
}
/**
* @notice Set a new UpdaterManager contract
* @dev Home(s) will initially be initialized using a trusted UpdaterManager contract;
* we will progressively decentralize by swapping the trusted contract with a new implementation
* that implements Updater bonding & slashing, and rules for Updater selection & rotation
* @param _updaterManager the new UpdaterManager contract
*/
function setUpdaterManager(address _updaterManager) external onlyOwner {
_setUpdaterManager(IUpdaterManager(_updaterManager));
_setUpdater(IUpdaterManager(_updaterManager).updater());
}
// ============ External Functions ============
/**
* @notice Dispatch the message to the destination domain & recipient
* @dev Format the message, insert its hash into Merkle tree,
* enqueue the new Merkle root, and emit `Dispatch` event with message information.
* @param _destinationDomain Domain of destination chain
* @param _recipientAddress Address of recipient on destination chain as bytes32
* @param _messageBody Raw bytes content of message
*/
function dispatch(
uint32 _destinationDomain,
bytes32 _recipientAddress,
bytes memory _messageBody
) external notFailed {
require(_messageBody.length <= MAX_MESSAGE_BODY_BYTES, "msg too long");
// get the next nonce for the destination domain, then increment it
uint32 _nonce = nonces[_destinationDomain];
nonces[_destinationDomain] = _nonce + 1;
// format the message into packed bytes
bytes memory _message = Message.formatMessage(
localDomain,
bytes32(uint256(uint160(msg.sender))),
_nonce,
_destinationDomain,
_recipientAddress,
_messageBody
);
// insert the hashed message into the Merkle tree
bytes32 _messageHash = keccak256(_message);
tree.insert(_messageHash);
// enqueue the new Merkle root after inserting the message
queue.enqueue(root());
// Emit Dispatch event with message information
// note: leafIndex is count() - 1 since new leaf has already been inserted
emit Dispatch(
_messageHash,
count() - 1,
_destinationAndNonce(_destinationDomain, _nonce),
committedRoot,
_message
);
}
/**
* @notice Submit a signature from the Updater "notarizing" a root,
* which updates the Home contract's `committedRoot`,
* and publishes the signature which will be relayed to Replica contracts
* @dev emits Update event
* @dev If _newRoot is not contained in the queue,
* the Update is a fraudulent Improper Update, so
* the Updater is slashed & Home is set to FAILED state
* @param _committedRoot Current updated merkle root which the update is building off of
* @param _newRoot New merkle root to update the contract state to
* @param _signature Updater signature on `_committedRoot` and `_newRoot`
*/
function update(
bytes32 _committedRoot,
bytes32 _newRoot,
bytes memory _signature
) external notFailed {
// check that the update is not fraudulent;
// if fraud is detected, Updater is slashed & Home is set to FAILED state
if (improperUpdate(_committedRoot, _newRoot, _signature)) return;
// clear all of the intermediate roots contained in this update from the queue
while (true) {
bytes32 _next = queue.dequeue();
if (_next == _newRoot) break;
}
// update the Home state with the latest signed root & emit event
committedRoot = _newRoot;
emit Update(localDomain, _committedRoot, _newRoot, _signature);
}
/**
* @notice Suggest an update for the Updater to sign and submit.
* @dev If queue is empty, null bytes returned for both
* (No update is necessary because no messages have been dispatched since the last update)
* @return _committedRoot Latest root signed by the Updater
* @return _new Latest enqueued Merkle root
*/
function suggestUpdate()
external
view
returns (bytes32 _committedRoot, bytes32 _new)
{
if (queue.length() != 0) {
_committedRoot = committedRoot;
_new = queue.lastItem();
}
}
/**
* @notice Called by external agent. Checks that signatures on two sets of
* roots are valid and that the new roots conflict with each other. If both
* cases hold true, the contract is failed and a `DoubleUpdate` event is
* emitted.
* @dev When `fail()` is called on Home, updater is slashed.
* @param _oldRoot Old root shared between two conflicting updates
* @param _newRoot Array containing two conflicting new roots
* @param _signature Signature on `_oldRoot` and `_newRoot`[0]
* @param _signature2 Signature on `_oldRoot` and `_newRoot`[1]
*/
function doubleUpdate(
bytes32 _oldRoot,
bytes32[2] calldata _newRoot,
bytes calldata _signature,
bytes calldata _signature2
) external notFailed {
if (
NomadBase._isUpdaterSignature(_oldRoot, _newRoot[0], _signature) &&
NomadBase._isUpdaterSignature(_oldRoot, _newRoot[1], _signature2) &&
_newRoot[0] != _newRoot[1]
) {
_fail();
emit DoubleUpdate(_oldRoot, _newRoot, _signature, _signature2);
}
}
// ============ Public Functions ============
/**
* @notice Hash of Home domain concatenated with "NOMAD"
*/
function homeDomainHash() public view override returns (bytes32) {
return _homeDomainHash(localDomain);
}
/**
* @notice Check if an Update is an Improper Update;
* if so, slash the Updater and set the contract to FAILED state.
*
* An Improper Update is an update building off of the Home's `committedRoot`
* for which the `_newRoot` does not currently exist in the Home's queue.
* This would mean that message(s) that were not truly
* dispatched on Home were falsely included in the signed root.
*
* An Improper Update will only be accepted as valid by the Replica
* If an Improper Update is attempted on Home,
* the Updater will be slashed immediately.
* If an Improper Update is submitted to the Replica,
* it should be relayed to the Home contract using this function
* in order to slash the Updater with an Improper Update.
*
* An Improper Update submitted to the Replica is only valid
* while the `_oldRoot` is still equal to the `committedRoot` on Home;
* if the `committedRoot` on Home has already been updated with a valid Update,
* then the Updater should be slashed with a Double Update.
* @dev Reverts (and doesn't slash updater) if signature is invalid or
* update not current
* @param _oldRoot Old merkle tree root (should equal home's committedRoot)
* @param _newRoot New merkle tree root
* @param _signature Updater signature on `_oldRoot` and `_newRoot`
* @return TRUE if update was an Improper Update (implying Updater was slashed)
*/
function improperUpdate(
bytes32 _oldRoot,
bytes32 _newRoot,
bytes memory _signature
) public notFailed returns (bool) {
require(
_isUpdaterSignature(_oldRoot, _newRoot, _signature),
"!updater sig"
);
require(_oldRoot == committedRoot, "not a current update");
// if the _newRoot is not currently contained in the queue,
// slash the Updater and set the contract to FAILED state
if (!queue.contains(_newRoot)) {
_fail();
emit ImproperUpdate(_oldRoot, _newRoot, _signature);
return true;
}
// if the _newRoot is contained in the queue,
// this is not an improper update
return false;
}
// ============ Internal Functions ============
/**
* @notice Set the UpdaterManager
* @param _updaterManager Address of the UpdaterManager
*/
function _setUpdaterManager(IUpdaterManager _updaterManager) internal {
require(
Address.isContract(address(_updaterManager)),
"!contract updaterManager"
);
updaterManager = IUpdaterManager(_updaterManager);
emit NewUpdaterManager(address(_updaterManager));
}
/**
* @notice Slash the Updater and set contract state to FAILED
* @dev Called when fraud is proven (Improper Update or Double Update)
*/
function _fail() internal {
// set contract to FAILED
state = States.Failed;
// slash Updater
updaterManager.slashUpdater(msg.sender);
emit UpdaterSlashed(updater, msg.sender);
}
/**
* @notice Internal utility function that combines
* `_destination` and `_nonce`.
* @dev Both destination and nonce should be less than 2^32 - 1
* @param _destination Domain of destination chain
* @param _nonce Current nonce for given destination chain
* @return Returns (`_destination` << 32) & `_nonce`
*/
function _destinationAndNonce(uint32 _destination, uint32 _nonce)
internal
pure
returns (uint64)
{
return (uint64(_destination) << 32) | _nonce;
}
}
packages/contracts-core/contracts/Merkle.sol
// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity 0.7.6;
// ============ Internal Imports ============
import {MerkleLib} from "./libs/Merkle.sol";
/**
* @title MerkleTreeManager
* @author Illusory Systems Inc.
* @notice Contains a Merkle tree instance and
* exposes view functions for the tree.
*/
contract MerkleTreeManager {
// ============ Libraries ============
using MerkleLib for MerkleLib.Tree;
MerkleLib.Tree public tree;
// ============ Upgrade Gap ============
// gap for upgrade safety
uint256[49] private __GAP;
// ============ Public Functions ============
/**
* @notice Calculates and returns tree's current root
*/
function root() public view returns (bytes32) {
return tree.root();
}
/**
* @notice Returns the number of inserted leaves in the tree (current index)
*/
function count() public view returns (uint256) {
return tree.count;
}
}
packages/contracts-core/contracts/NomadBase.sol
// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity 0.7.6;
// ============ Internal Imports ============
import {Message} from "./libs/Message.sol";
// ============ External Imports ============
import {ECDSA} from "@openzeppelin/contracts/cryptography/ECDSA.sol";
import {Initializable} from "@openzeppelin/contracts-upgradeable/proxy/Initializable.sol";
import {OwnableUpgradeable} from "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
/**
* @title NomadBase
* @author Illusory Systems Inc.
* @notice Shared utilities between Home and Replica.
*/
abstract contract NomadBase is Initializable, OwnableUpgradeable {
// ============ Enums ============
// States:
// 0 - UnInitialized - before initialize function is called
// note: the contract is initialized at deploy time, so it should never be in this state
// 1 - Active - as long as the contract has not become fraudulent
// 2 - Failed - after a valid fraud proof has been submitted;
// contract will no longer accept updates or new messages
enum States {
UnInitialized,
Active,
Failed
}
// ============ Immutable Variables ============
// Domain of chain on which the contract is deployed
uint32 public immutable localDomain;
// ============ Public Variables ============
// Address of bonded Updater
address public updater;
// Current state of contract
States public state;
// The latest root that has been signed by the Updater
bytes32 public committedRoot;
// ============ Upgrade Gap ============
// gap for upgrade safety
uint256[47] private __GAP;
// ============ Events ============
/**
* @notice Emitted when update is made on Home
* or unconfirmed update root is submitted on Replica
* @param homeDomain Domain of home contract
* @param oldRoot Old merkle root
* @param newRoot New merkle root
* @param signature Updater's signature on `oldRoot` and `newRoot`
*/
event Update(
uint32 indexed homeDomain,
bytes32 indexed oldRoot,
bytes32 indexed newRoot,
bytes signature
);
/**
* @notice Emitted when Updater is rotated
* @param oldUpdater The address of the old updater
* @param newUpdater The address of the new updater
*/
event NewUpdater(address oldUpdater, address newUpdater);
// ============ Constructor ============
constructor(uint32 _localDomain) {
localDomain = _localDomain;
}
// ============ Initializer ============
function __NomadBase_initialize(address _updater) internal initializer {
__Ownable_init();
_setUpdater(_updater);
state = States.Active;
}
// ============ Public Functions ============
/**
* @notice Hash of Home domain concatenated with "NOMAD"
*/
function homeDomainHash() public view virtual returns (bytes32);
// ============ Internal Functions ============
/**
* @notice Hash of Home domain concatenated with "NOMAD"
* @param _homeDomain the Home domain to hash
*/
function _homeDomainHash(uint32 _homeDomain)
internal
pure
returns (bytes32)
{
return keccak256(abi.encodePacked(_homeDomain, "NOMAD"));
}
/**
* @notice Set the Updater
* @param _newUpdater Address of the new Updater
*/
function _setUpdater(address _newUpdater) internal {
address _oldUpdater = updater;
updater = _newUpdater;
emit NewUpdater(_oldUpdater, _newUpdater);
}
/**
* @notice Checks that signature was signed by Updater
* @param _oldRoot Old merkle root
* @param _newRoot New merkle root
* @param _signature Signature on `_oldRoot` and `_newRoot`
* @return TRUE iff signature is valid signed by updater
**/
function _isUpdaterSignature(
bytes32 _oldRoot,
bytes32 _newRoot,
bytes memory _signature
) internal view returns (bool) {
bytes32 _digest = keccak256(
abi.encodePacked(homeDomainHash(), _oldRoot, _newRoot)
);
_digest = ECDSA.toEthSignedMessageHash(_digest);
return (ECDSA.recover(_digest, _signature) == updater);
}
/**
* @dev should be impossible to renounce ownership;
* we override OpenZeppelin OwnableUpgradeable's
* implementation of renounceOwnership to make it a no-op
*/
function renounceOwnership() public override onlyOwner {
// do nothing
}
}
packages/contracts-core/contracts/Queue.sol
// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity 0.7.6;
// ============ Internal Imports ============
import {QueueLib} from "./libs/Queue.sol";
// ============ External Imports ============
import {Initializable} from "@openzeppelin/contracts-upgradeable/proxy/Initializable.sol";
/**
* @title QueueManager
* @author Illusory Systems Inc.
* @notice Contains a queue instance and
* exposes view functions for the queue.
**/
contract QueueManager is Initializable {
// ============ Libraries ============
using QueueLib for QueueLib.Queue;
QueueLib.Queue internal queue;
// ============ Upgrade Gap ============
// gap for upgrade safety
uint256[49] private __GAP;
// ============ Initializer ============
function __QueueManager_initialize() internal initializer {
queue.initialize();
}
// ============ Public Functions ============
/**
* @notice Returns number of elements in queue
*/
function queueLength() external view returns (uint256) {
return queue.length();
}
/**
* @notice Returns TRUE iff `_item` is in the queue
*/
function queueContains(bytes32 _item) external view returns (bool) {
return queue.contains(_item);
}
/**
* @notice Returns last item enqueued to the queue
*/
function queueEnd() external view returns (bytes32) {
return queue.lastItem();
}
}
packages/contracts-core/contracts/Replica.sol
// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity 0.7.6;
// ============ Internal Imports ============
import {Version0} from "./Version0.sol";
import {NomadBase} from "./NomadBase.sol";
import {MerkleLib} from "./libs/Merkle.sol";
import {Message} from "./libs/Message.sol";
import {IMessageRecipient} from "./interfaces/IMessageRecipient.sol";
// ============ External Imports ============
import {TypedMemView} from "@summa-tx/memview-sol/contracts/TypedMemView.sol";
/**
* @title Replica
* @author Illusory Systems Inc.
* @notice Track root updates on Home,
* prove and dispatch messages to end recipients.
*/
contract Replica is Version0, NomadBase {
// ============ Libraries ============
using MerkleLib for MerkleLib.Tree;
using TypedMemView for bytes;
using TypedMemView for bytes29;
using Message for bytes29;
// ============ Constants ============
bytes32 public constant LEGACY_STATUS_NONE = bytes32(0);
bytes32 public constant LEGACY_STATUS_PROVEN = bytes32(uint256(1));
bytes32 public constant LEGACY_STATUS_PROCESSED = bytes32(uint256(2));
// ============ Public Storage ============
// Domain of home chain
uint32 public remoteDomain;
// Number of seconds to wait before root becomes confirmable
uint256 public optimisticSeconds;
// re-entrancy guard
uint8 private entered;
// Mapping of roots to allowable confirmation times
mapping(bytes32 => uint256) public confirmAt;
// Mapping of message leaves to MessageStatus
mapping(bytes32 => bytes32) public messages;
// ============ Upgrade Gap ============
// gap for upgrade safety
uint256[45] private __GAP;
// ============ Events ============
/**
* @notice Emitted when message is processed
* @param messageHash The keccak256 hash of the message that was processed
* @param success TRUE if the call was executed successfully,
* FALSE if the call reverted or threw
* @param returnData the return data from the external call
*/
event Process(
bytes32 indexed messageHash,
bool indexed success,
bytes indexed returnData
);
/**
* @notice Emitted when the value for optimisticTimeout is set
* @param timeout The new value for optimistic timeout
*/
event SetOptimisticTimeout(uint256 timeout);
/**
* @notice Emitted when a root's confirmation is modified by governance
* @param root The root for which confirmAt has been set
* @param previousConfirmAt The previous value of confirmAt
* @param newConfirmAt The new value of confirmAt
*/
event SetConfirmation(
bytes32 indexed root,
uint256 previousConfirmAt,
uint256 newConfirmAt
);
// ============ Constructor ============
constructor(uint32 _localDomain) NomadBase(_localDomain) {}
// ============ Initializer ============
/**
* @notice Initialize the replica
* @dev Performs the following action:
* - initializes inherited contracts
* - initializes re-entrancy guard
* - sets remote domain
* - sets a trusted root, and pre-approves messages under it
* - sets the optimistic timer
* @param _remoteDomain The domain of the Home contract this follows
* @param _updater The EVM id of the updater
* @param _committedRoot A trusted root from which to start the Replica
* @param _optimisticSeconds The time a new root must wait to be confirmed
*/
function initialize(
uint32 _remoteDomain,
address _updater,
bytes32 _committedRoot,
uint256 _optimisticSeconds
) public initializer {
__NomadBase_initialize(_updater);
// set storage variables
entered = 1;
remoteDomain = _remoteDomain;
committedRoot = _committedRoot;
// pre-approve the committed root.
if (_committedRoot != bytes32(0)) confirmAt[_committedRoot] = 1;
_setOptimisticTimeout(_optimisticSeconds);
}
// ============ External Functions ============
/**
* @notice Called by external agent. Submits the signed update's new root,
* marks root's allowable confirmation time, and emits an `Update` event.
* @dev Reverts if update doesn't build off latest committedRoot
* or if signature is invalid.
* @param _oldRoot Old merkle root
* @param _newRoot New merkle root
* @param _signature Updater's signature on `_oldRoot` and `_newRoot`
*/
function update(
bytes32 _oldRoot,
bytes32 _newRoot,
bytes memory _signature
) external {
// ensure that update is building off the last submitted root
require(_oldRoot == committedRoot, "not current update");
// validate updater signature
require(
_isUpdaterSignature(_oldRoot, _newRoot, _signature),
"!updater sig"
);
// Hook for future use
_beforeUpdate();
// set the new root's confirmation timer
confirmAt[_newRoot] = block.timestamp + optimisticSeconds;
// update committedRoot
committedRoot = _newRoot;
emit Update(remoteDomain, _oldRoot, _newRoot, _signature);
}
/**
* @notice If necessary, attempts to prove the validity of provided
* `_message`. If the message is successfully proven, then tries to
* process the message
* @dev Reverts if `prove` call returns false
* @param _message A Nomad message coming from another chain :)
* @param _proof Merkle proof of inclusion for message's leaf (optional if
* the message has already been proven).
* @param _index Index of leaf in home's merkle tree (optional if the
* message has already been proven).
*/
function proveAndProcess(
bytes memory _message,
bytes32[32] calldata _proof,
uint256 _index
) external {
bytes32 _messageHash = keccak256(_message);
require(
acceptableRoot(messages[_messageHash]) ||
prove(_messageHash, _proof, _index),
"!prove"
);
process(_message);
}
/**
* @notice Given formatted message, attempts to dispatch
* message payload to end recipient.
* @dev Recipient must implement a `handle` method (refer to IMessageRecipient.sol)
* Reverts if formatted message's destination domain is not the Replica's domain,
* if message has not been proven,
* or if not enough gas is provided for the dispatch transaction.
* @param _message Formatted message
* @return _success TRUE iff dispatch transaction succeeded
*/
function process(bytes memory _message) public returns (bool _success) {
// ensure message was meant for this domain
bytes29 _m = _message.ref(0);
require(_m.destination() == localDomain, "!destination");
// ensure message has been proven
bytes32 _messageHash = _m.keccak();
require(acceptableRoot(messages[_messageHash]), "!proven");
// check re-entrancy guard
require(entered == 1, "!reentrant");
entered = 0;
// update message status as processed
messages[_messageHash] = LEGACY_STATUS_PROCESSED;
// call handle function
IMessageRecipient(_m.recipientAddress()).handle(
_m.origin(),
_m.nonce(),
_m.sender(),
_m.body().clone()
);
// emit process results
emit Process(_messageHash, true, "");
// reset re-entrancy guard
entered = 1;
// return true
return true;
}
// ============ External Owner Functions ============
/**
* @notice Set optimistic timeout period for new roots
* @dev Only callable by owner (Governance)
* @param _optimisticSeconds New optimistic timeout period
*/
function setOptimisticTimeout(uint256 _optimisticSeconds)
external
onlyOwner
{
_setOptimisticTimeout(_optimisticSeconds);
}
/**
* @notice Set Updater role
* @dev MUST ensure that all roots signed by previous Updater have
* been relayed before calling. Only callable by owner (Governance)
* @param _updater New Updater
*/
function setUpdater(address _updater) external onlyOwner {
_setUpdater(_updater);
}
/**
* @notice Set confirmAt for a given root
* @dev To be used if in the case that fraud is proven
* and roots need to be deleted / added. Only callable by owner (Governance)
* @param _root The root for which to modify confirm time
* @param _confirmAt The new confirmation time. Set to 0 to "delete" a root.
*/
function setConfirmation(bytes32 _root, uint256 _confirmAt)
external
onlyOwner
{
require(_root != bytes32(0) || _confirmAt == 0, "can't set zero root");
uint256 _previousConfirmAt = confirmAt[_root];
confirmAt[_root] = _confirmAt;
emit SetConfirmation(_root, _previousConfirmAt, _confirmAt);
}
// ============ Public Functions ============
/**
* @notice Check that the root has been submitted
* and that the optimistic timeout period has expired,
* meaning the root can be processed
* @param _root the Merkle root, submitted in an update, to check
* @return TRUE iff root has been submitted & timeout has expired
*/
function acceptableRoot(bytes32 _root) public view returns (bool) {
// this is backwards-compatibility for messages proven/processed
// under previous versions
if (_root == LEGACY_STATUS_PROVEN) return true;
if (_root == LEGACY_STATUS_PROCESSED || _root == LEGACY_STATUS_NONE)
return false;
uint256 _time = confirmAt[_root];
if (_time == 0) {
return false;
}
return block.timestamp >= _time;
}
/**
* @notice Attempts to prove the validity of message given its leaf, the
* merkle proof of inclusion for the leaf, and the index of the leaf.
* @dev Reverts if message's MessageStatus != None (i.e. if message was
* already proven or processed)
* @dev For convenience, we allow proving against any previous root.
* This means that witnesses never need to be updated for the new root
* @param _leaf Leaf of message to prove
* @param _proof Merkle proof of inclusion for leaf
* @param _index Index of leaf in home's merkle tree
* @return Returns true if proof was valid and `prove` call succeeded
**/
function prove(
bytes32 _leaf,
bytes32[32] calldata _proof,
uint256 _index
) public returns (bool) {
// ensure that message has not been processed
// Note that this allows re-proving under a new root.
require(
messages[_leaf] != LEGACY_STATUS_PROCESSED,
"already processed"
);
// calculate the expected root based on the proof
bytes32 _calculatedRoot = MerkleLib.branchRoot(_leaf, _proof, _index);
// if the root is valid, change status to Proven
if (acceptableRoot(_calculatedRoot)) {
messages[_leaf] = _calculatedRoot;
return true;
}
return false;
}
/**
* @notice Hash of Home domain concatenated with "NOMAD"
*/
function homeDomainHash() public view override returns (bytes32) {
return _homeDomainHash(remoteDomain);
}
// ============ Internal Functions ============
/**
* @notice Set optimistic timeout period for new roots
* @dev Called by owner (Governance) or at initialization
* @param _optimisticSeconds New optimistic timeout period
*/
function _setOptimisticTimeout(uint256 _optimisticSeconds) internal {
// This allows us to initialize the value to be very low in test envs,
// but does not allow governance action to lower a production env below
// the safe value
uint256 _current = optimisticSeconds;
if (_current != 0 && _current > 1500)
require(_optimisticSeconds >= 1500, "optimistic timeout too low");
// ensure the optimistic timeout is less than 1 year
// (prevents overflow when adding block.timestamp)
require(_optimisticSeconds < 31536000, "optimistic timeout too high");
// set the optimistic timeout
optimisticSeconds = _optimisticSeconds;
emit SetOptimisticTimeout(_optimisticSeconds);
}
/// @notice Hook for potential future use
// solhint-disable-next-line no-empty-blocks
function _beforeUpdate() internal {}
}
packages/contracts-core/contracts/Version0.sol
// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity 0.7.6;
/**
* @title Version0
* @notice Version getter for contracts
**/
abstract contract Version0 {
uint8 public constant VERSION = 0;
}
// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity 0.7.6;
// ============ Internal Imports ============
import {Home} from "./Home.sol";
import {Replica} from "./Replica.sol";
import {TypeCasts} from "./libs/TypeCasts.sol";
// ============ External Imports ============
import {ECDSA} from "@openzeppelin/contracts/cryptography/ECDSA.sol";
import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
/**
* @title XAppConnectionManager
* @author Illusory Systems Inc.
* @notice Manages a registry of local Replica contracts
* for remote Home domains. Accepts Watcher signatures
* to un-enroll Replicas attached to fraudulent remote Homes
*/
contract XAppConnectionManager is Ownable {
// ============ Public Storage ============
// Home contract
Home public home;
// local Replica address => remote Home domain
mapping(address => uint32) public replicaToDomain;
// remote Home domain => local Replica address
mapping(uint32 => address) public domainToReplica;
// watcher address => replica remote domain => has/doesn't have permission
mapping(address => mapping(uint32 => bool)) private watcherPermissions;
// ============ Events ============
/**
* @notice Emitted when a new Replica is enrolled / added
* @param domain the remote domain of the Home contract for the Replica
* @param replica the address of the Replica
*/
event ReplicaEnrolled(uint32 indexed domain, address replica);
/**
* @notice Emitted when a new Replica is un-enrolled / removed
* @param domain the remote domain of the Home contract for the Replica
* @param replica the address of the Replica
*/
event ReplicaUnenrolled(uint32 indexed domain, address replica);
/**
* @notice Emitted when Watcher permissions are changed
* @param domain the remote domain of the Home contract for the Replica
* @param watcher the address of the Watcher
* @param access TRUE if the Watcher was given permissions, FALSE if permissions were removed
*/
event WatcherPermissionSet(
uint32 indexed domain,
address watcher,
bool access
);
// ============ Constructor ============
// solhint-disable-next-line no-empty-blocks
constructor() Ownable() {}
// ============ External Functions ============
/**
* @notice Un-Enroll a replica contract
* in the case that fraud was detected on the Home
* @dev in the future, if fraud occurs on the Home contract,
* the Watcher will submit their signature directly to the Home
* and it can be relayed to all remote chains to un-enroll the Replicas
* @param _domain the remote domain of the Home contract for the Replica
* @param _updater the address of the Updater for the Home contract (also stored on Replica)
* @param _signature signature of watcher on (domain, replica address, updater address)
*/
function unenrollReplica(
uint32 _domain,
bytes32 _updater,
bytes memory _signature
) external {
// ensure that the replica is currently set
address _replica = domainToReplica[_domain];
require(_replica != address(0), "!replica exists");
// ensure that the signature is on the proper updater
require(
Replica(_replica).updater() == TypeCasts.bytes32ToAddress(_updater),
"!current updater"
);
// get the watcher address from the signature
// and ensure that the watcher has permission to un-enroll this replica
address _watcher = _recoverWatcherFromSig(
_domain,
TypeCasts.addressToBytes32(_replica),
_updater,
_signature
);
require(watcherPermissions[_watcher][_domain], "!valid watcher");
// remove the replica from mappings
_clearReplica(_replica);
}
/**
* @notice Set the address of the local Home contract
* @param _home the address of the local Home contract
*/
function setHome(address _home) external onlyOwner {
home = Home(_home);
}
/**
* @notice Allow Owner to enroll Replica contract
* @param _replica the address of the Replica
* @param _domain the remote domain of the Home contract for the Replica
*/
function ownerEnrollReplica(address _replica, uint32 _domain)
external
onlyOwner
{
// un-enroll any existing replica or domain
_clearReplica(_replica);
_clearDomain(_domain);
// add replica and domain to two-way mapping
replicaToDomain[_replica] = _domain;
domainToReplica[_domain] = _replica;
emit ReplicaEnrolled(_domain, _replica);
}
/**
* @notice Allow Owner to un-enroll Replica contract
* @param _replica the address of the Replica
*/
function ownerUnenrollReplica(address _replica) external onlyOwner {
_clearReplica(_replica);
}
/**
* @notice Allow Owner to set Watcher permissions for a Replica
* @param _watcher the address of the Watcher
* @param _domain the remote domain of the Home contract for the Replica
* @param _access TRUE to give the Watcher permissions, FALSE to remove permissions
*/
function setWatcherPermission(
address _watcher,
uint32 _domain,
bool _access
) external onlyOwner {
watcherPermissions[_watcher][_domain] = _access;
emit WatcherPermissionSet(_domain, _watcher, _access);
}
/**
* @notice Query local domain from Home
* @return local domain
*/
function localDomain() external view returns (uint32) {
return home.localDomain();
}
/**
* @notice Get access permissions for the watcher on the domain
* @param _watcher the address of the watcher
* @param _domain the domain to check for watcher permissions
* @return TRUE iff _watcher has permission to un-enroll replicas on _domain
*/
function watcherPermission(address _watcher, uint32 _domain)
external
view
returns (bool)
{
return watcherPermissions[_watcher][_domain];
}
// ============ Public Functions ============
/**
* @notice Check whether _replica is enrolled
* @param _replica the replica to check for enrollment
* @return TRUE iff _replica is enrolled
*/
function isReplica(address _replica) public view returns (bool) {
return replicaToDomain[_replica] != 0;
}
// ============ Internal Functions ============
/**
* @notice Remove the replica from the two-way mappings
* @param _replica replica to un-enroll
*/
function _clearReplica(address _replica) internal {
uint32 _currentDomain = replicaToDomain[_replica];
if (_currentDomain != 0) {
domainToReplica[_currentDomain] = address(0);
replicaToDomain[_replica] = 0;
emit ReplicaUnenrolled(_currentDomain, _replica);
}
}
/**
* @notice remove the domain from the two-way mapping
* @param _domain domain to un-enroll
*/
function _clearDomain(uint32 _domain) internal {
address _currentReplica = domainToReplica[_domain];
if (_currentReplica != address(0)) {
domainToReplica[_domain] = address(0);
replicaToDomain[_currentReplica] = 0;
emit ReplicaUnenrolled(_domain, _currentReplica);
}
}
/**
* @notice Get the Watcher address from the provided signature
* @return address of watcher that signed
*/
function _recoverWatcherFromSig(
uint32 _domain,
bytes32 _replica,
bytes32 _updater,
bytes memory _signature
) internal view returns (address) {
bytes32 _homeDomainHash = Replica(TypeCasts.bytes32ToAddress(_replica))
.homeDomainHash();
bytes32 _digest = keccak256(
abi.encodePacked(_homeDomainHash, _domain, _updater)
);
_digest = ECDSA.toEthSignedMessageHash(_digest);
return ECDSA.recover(_digest, _signature);
}
/**
* @dev should be impossible to renounce ownership;
* we override OpenZeppelin Ownable implementation
* of renounceOwnership to make it a no-op
*/
function renounceOwnership() public override onlyOwner {
// do nothing
}
}
// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity 0.7.6;
import "@summa-tx/memview-sol/contracts/TypedMemView.sol";
import {TypeCasts} from "./TypeCasts.sol";
/**
* @title Message Library
* @author Illusory Systems Inc.
* @notice Library for formatted messages used by Home and Replica.
**/
library Message {
using TypedMemView for bytes;
using TypedMemView for bytes29;
// Number of bytes in formatted message before `body` field
uint256 internal constant PREFIX_LENGTH = 76;
/**
* @notice Returns formatted (packed) message with provided fields
* @param _originDomain Domain of home chain
* @param _sender Address of sender as bytes32
* @param _nonce Destination-specific nonce
* @param _destinationDomain Domain of destination chain
* @param _recipient Address of recipient on destination chain as bytes32
* @param _messageBody Raw bytes of message body
* @return Formatted message
**/
function formatMessage(
uint32 _originDomain,
bytes32 _sender,
uint32 _nonce,
uint32 _destinationDomain,
bytes32 _recipient,
bytes memory _messageBody
) internal pure returns (bytes memory) {
return
abi.encodePacked(
_originDomain,
_sender,
_nonce,
_destinationDomain,
_recipient,
_messageBody
);
}
/**
* @notice Returns leaf of formatted message with provided fields.
* @param _origin Domain of home chain
* @param _sender Address of sender as bytes32
* @param _nonce Destination-specific nonce number
* @param _destination Domain of destination chain
* @param _recipient Address of recipient on destination chain as bytes32
* @param _body Raw bytes of message body
* @return Leaf (hash) of formatted message
**/
function messageHash(
uint32 _origin,
bytes32 _sender,
uint32 _nonce,
uint32 _destination,
bytes32 _recipient,
bytes memory _body
) internal pure returns (bytes32) {
return
keccak256(
formatMessage(
_origin,
_sender,
_nonce,
_destination,
_recipient,
_body
)
);
}
/// @notice Returns message's origin field
function origin(bytes29 _message) internal pure returns (uint32) {
return uint32(_message.indexUint(0, 4));
}
/// @notice Returns message's sender field
function sender(bytes29 _message) internal pure returns (bytes32) {
return _message.index(4, 32);
}
/// @notice Returns message's nonce field
function nonce(bytes29 _message) internal pure returns (uint32) {
return uint32(_message.indexUint(36, 4));
}
/// @notice Returns message's destination field
function destination(bytes29 _message) internal pure returns (uint32) {
return uint32(_message.indexUint(40, 4));
}
/// @notice Returns message's recipient field as bytes32
function recipient(bytes29 _message) internal pure returns (bytes32) {
return _message.index(44, 32);
}
/// @notice Returns message's recipient field as an address
function recipientAddress(bytes29 _message)
internal
pure
returns (address)
{
return TypeCasts.bytes32ToAddress(recipient(_message));
}
/// @notice Returns message's body field as bytes29 (refer to TypedMemView library for details on bytes29 type)
function body(bytes29 _message) internal pure returns (bytes29) {
return _message.slice(PREFIX_LENGTH, _message.len() - PREFIX_LENGTH, 0);
}
function leaf(bytes29 _message) internal view returns (bytes32) {
return
messageHash(
origin(_message),
sender(_message),
nonce(_message),
destination(_message),
recipient(_message),
TypedMemView.clone(body(_message))
);
}
}
packages/contracts-core/contracts/libs/Queue.sol
// SPDX-License-Identifier: MIT OR Apache-2.0
pragma solidity 0.7.6;
/**
* @title QueueLib
* @author Illusory Systems Inc.
* @notice Library containing queue struct and operations for queue used by
* Home and Replica.
**/
library QueueLib {
/**
* @notice Queue struct
* @dev Internally keeps track of the `first` and `last` elements through
* indices and a mapping of indices to enqueued elements.
**/
struct Queue {
uint128 first;
uint128 last;
mapping(uint256 => bytes32) queue;
}
/**
* @notice Initializes the queue
* @dev Empty state denoted by _q.first > q._last. Queue initialized
* with _q.first = 1 and _q.last = 0.
**/
function initialize(Queue storage _q) internal {
if (_q.first == 0) {
_q.first = 1;
}
}
/**
* @notice Enqueues a single new element
* @param _item New element to be enqueued
* @return _last Index of newly enqueued element
**/
function enqueue(Queue storage _q, bytes32 _item)
internal
returns (uint128 _last)
{
_last = _q.last + 1;
_q.last = _last;
if (_item != bytes32(0)) {
// saves gas if we're queueing 0
_q.queue[_last] = _item;
}
}
/**
* @notice Dequeues element at front of queue
* @dev Removes dequeued element from storage
* @return _item Dequeued element
**/
function dequeue(Queue storage _q) internal returns (bytes32 _item) {
uint128 _last = _q.last;
uint128 _first = _q.first;
require(_length(_last, _first) != 0, "Empty");
_item = _q.queue[_first];
if (_item != bytes32(0)) {
// saves gas if we're dequeuing 0
delete _q.queue[_first];
}
_q.first = _first + 1;
}
/**
* @notice Batch enqueues several elements
* @param _items Array of elements to be enqueued
* @return _last Index of last enqueued element
**/
function enqueue(Queue storage _q, bytes32[] memory _items)
internal
returns (uint128 _last)
{
_last = _q.last;
for (uint256 i = 0; i < _items.length; i += 1) {
_last += 1;
bytes32 _item = _items[i];
if (_item != bytes32(0)) {
_q.queue[_last] = _item;
}
}
_q.last = _last;
}
/**
* @notice Batch dequeues `_number` elements
* @dev Reverts if `_number` > queue length
* @param _number Number of elements to dequeue
* @return Array of dequeued elements
**/
function dequeue(Queue storage _q, uint256 _number)
internal
returns (bytes32[] memory)
{
uint128 _last = _q.last;
uint128 _first = _q.first;
// Cannot underflow unless state is corrupted
require(_length(_last, _first) >= _number, "Insufficient");
bytes32[] memory _items = new bytes32[](_number);
for (uint256 i = 0; i < _number; i++) {
_items[i] = _q.queue[_first];
delete _q.queue[_first];
_first++;
}
_q.first = _first;
return _items;
}
/**
* @notice Returns true if `_item` is in the queue and false if otherwise
* @dev Linearly scans from _q.first to _q.last looking for `_item`
* @param _item Item being searched for in queue
* @return True if `_item` currently exists in queue, false if otherwise
**/
function contains(Queue storage _q, bytes32 _item)
internal
view
returns (bool)
{
for (uint256 i = _q.first; i <= _q.last; i++) {
if (_q.queue[i] == _item) {
return true;
}
}
return false;
}
/// @notice Returns last item in queue
/// @dev Returns bytes32(0) if queue empty
function lastItem(Queue storage _q) internal view returns (bytes32) {
return _q.queue[_q.last];
}
/// @notice Returns element at front of queue without removing element
/// @dev Reverts if queue is empty
function peek(Queue storage _q) internal view returns (bytes32 _item) {
require(!isEmpty(_q), "Empty");
_item = _q.queue[_q.first];
}
/// @notice Returns true if queue is empty and false if otherwise
function isEmpty(Queue storage _q) internal view returns (bool) {
return _q.last < _q.first;
}
/// @notice Returns number of elements in queue
function length(Queue storage _q) internal view returns (uint256) {
uint128 _last = _q.last;
uint128 _first = _q.first;
// Cannot underflow unless state is corrupted
return _length(_last, _first);
}
/// @notice Returns number of elements between `_last` and `_first` (used internally)
function _length(uint128 _last, uint128 _first)
internal
pure
returns (uint256)
{
return uint256(_last + 1 - _first);
}
}
