Contract Name:
ERC677MultiBridgeToken
Contract Source Code:
File 1 of 1 : ERC677MultiBridgeToken
pragma solidity 0.5.10;
/**
* @dev Collection of functions related to the address type,
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* This test is non-exhaustive, and there may be false-negatives: during the
* execution of a contract's constructor, its address will be reported as
* not containing a contract.
*
* > It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*/
function isContract(address account) internal view returns (bool) {
// This method relies in 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;
}
}
interface IDistribution {
function supply() external view returns(uint256);
function poolAddress(uint8) external view returns(address);
}
contract Sacrifice {
constructor(address payable _recipient) public payable {
selfdestruct(_recipient);
}
}
interface IERC677MultiBridgeToken {
function transfer(address _to, uint256 _value) external returns (bool);
function transferDistribution(address _to, uint256 _value) external returns (bool);
function transferFrom(address _from, address _to, uint256 _value) external returns (bool);
function balanceOf(address _account) external view returns (uint256);
}
/**
* @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.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be aplied to your functions to restrict their use to
* the owner.
*/
contract Ownable {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor () internal {
_owner = msg.sender;
emit OwnershipTransferred(address(0), _owner);
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(isOwner(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Returns true if the caller is the current owner.
*/
function isOwner() public view returns (bool) {
return msg.sender == _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 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 onlyOwner {
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
*/
function _transferOwnership(address newOwner) internal {
require(newOwner != address(0), "Ownable: new owner is the zero address");
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
/**
* @dev Interface of the ERC20 standard as defined in the EIP. Does not include
* the optional functions; to access them see `ERC20Detailed`.
*/
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.
*
* > 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);
}
/**
* @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, 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");
uint256 c = a - b;
return c;
}
/**
* @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) {
// 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-solidity/pull/522
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. Reverts 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) {
// Solidity only automatically asserts when dividing by 0
require(b > 0, "SafeMath: division by zero");
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts 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;
}
}
/**
* @title SafeERC20
* @dev Wrappers around ERC20 operations that throw on failure (when the token
* contract returns false). Tokens that return no value (and instead revert or
* throw on failure) are also supported, non-reverting calls are assumed to be
* successful.
* To use this library you can add a `using SafeERC20 for ERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeERC20 {
using SafeMath for uint256;
using Address for address;
function safeTransfer(IERC20 token, address to, uint256 value) internal {
callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
function safeApprove(IERC20 token, address spender, uint256 value) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
// solhint-disable-next-line max-line-length
require((value == 0) || (token.allowance(address(this), spender) == 0),
"SafeERC20: approve from non-zero to non-zero allowance"
);
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 newAllowance = token.allowance(address(this), spender).add(value);
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 newAllowance = token.allowance(address(this), spender).sub(value);
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function callOptionalReturn(IERC20 token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves.
// A Solidity high level call has three parts:
// 1. The target address is checked to verify it contains contract code
// 2. The call itself is made, and success asserted
// 3. The return value is decoded, which in turn checks the size of the returned data.
// solhint-disable-next-line max-line-length
require(address(token).isContract(), "SafeERC20: call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = address(token).call(data);
require(success, "SafeERC20: low-level call failed");
if (returndata.length > 0) { // Return data is optional
// solhint-disable-next-line max-line-length
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
/**
* @dev Implementation of the `IERC20` interface.
*
* This implementation was taken from
* https://github.com/OpenZeppelin/openzeppelin-contracts/blob/v2.3.0/contracts/token/ERC20/ERC20.sol
* This differs from the original one only in the definition for the `_balances`
* mapping: we made it `internal` instead of `private` since we use the `_balances`
* in the `ERC677BridgeToken` child contract to be able to transfer tokens to address(0)
* (see its `_superTransfer` function). The original OpenZeppelin implementation
* doesn't allow transferring to address(0).
*
* 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 `ERC20Mintable`.
*
* *For a detailed writeup see our guide [How to implement supply
* mechanisms](https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226).*
*
* 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`.
*/
contract ERC20 is IERC20 {
using SafeMath for uint256;
mapping (address => uint256) internal _balances; // CHANGED: not private to write a custom transfer method
mapping (address => mapping (address => uint256)) private _allowances;
uint256 private _totalSupply;
/**
* @dev See `IERC20.totalSupply`.
*/
function totalSupply() public view returns (uint256) {
return _totalSupply;
}
/**
* @dev See `IERC20.balanceOf`.
*/
function balanceOf(address account) public view returns (uint256) {
return _balances[account];
}
/**
* @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 returns (bool) {
_transfer(msg.sender, recipient, amount);
return true;
}
/**
* @dev See `IERC20.allowance`.
*/
function allowance(address owner, address spender) public view returns (uint256) {
return _allowances[owner][spender];
}
/**
* @dev See `IERC20.approve`.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 value) public returns (bool) {
_approve(msg.sender, spender, value);
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 `value`.
* - the caller must have allowance for `sender`'s tokens of at least
* `amount`.
*/
function transferFrom(address sender, address recipient, uint256 amount) public returns (bool) {
_transfer(sender, recipient, amount);
_approve(sender, msg.sender, _allowances[sender][msg.sender].sub(amount));
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 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 returns (bool) {
_approve(msg.sender, spender, _allowances[msg.sender][spender].sub(subtractedValue));
return true;
}
/**
* @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 {
require(sender != address(0), "ERC20: transfer from the zero address");
require(recipient != address(0), "ERC20: transfer to the zero address");
_balances[sender] = _balances[sender].sub(amount);
_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 {
require(account != address(0), "ERC20: mint to the zero address");
_totalSupply = _totalSupply.add(amount);
_balances[account] = _balances[account].add(amount);
emit Transfer(address(0), account, amount);
}
/**
* @dev Destoys `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 value) internal {
require(account != address(0), "ERC20: burn from the zero address");
_totalSupply = _totalSupply.sub(value);
_balances[account] = _balances[account].sub(value);
emit Transfer(account, address(0), value);
}
/**
* @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
*
* This is 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 value) internal {
require(owner != address(0), "ERC20: approve from the zero address");
require(spender != address(0), "ERC20: approve to the zero address");
_allowances[owner][spender] = value;
emit Approval(owner, spender, value);
}
/**
* @dev Destoys `amount` tokens from `account`.`amount` is then deducted
* from the caller's allowance.
*
* See `_burn` and `_approve`.
*/
function _burnFrom(address account, uint256 amount) internal {
_burn(account, amount);
_approve(account, msg.sender, _allowances[account][msg.sender].sub(amount));
}
}
/**
* @dev Optional functions from the ERC20 standard.
*/
contract ERC20Detailed is IERC20 {
string private _name;
string private _symbol;
uint8 private _decimals;
/**
* @dev Sets the values for `name`, `symbol`, and `decimals`. All three of
* these values are immutable: they can only be set once during
* construction.
*/
constructor (string memory name, string memory symbol, uint8 decimals) public {
_name = name;
_symbol = symbol;
_decimals = decimals;
}
/**
* @dev Returns the name of the token.
*/
function name() public view returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view returns (string memory) {
return _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.
*
* > Note that 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 returns (uint8) {
return _decimals;
}
}
/**
* @title ERC20Permittable
* @dev This is ERC20 contract extended by the `permit` function (see EIP712).
*/
contract ERC20Permittable is ERC20, ERC20Detailed {
string public constant version = "1";
// EIP712 niceties
bytes32 public DOMAIN_SEPARATOR;
// bytes32 public constant PERMIT_TYPEHASH = keccak256("Permit(address holder,address spender,uint256 nonce,uint256 expiry,bool allowed)");
bytes32 public constant PERMIT_TYPEHASH = 0xea2aa0a1be11a07ed86d755c93467f4f82362b452371d1ba94d1715123511acb;
mapping(address => uint256) public nonces;
mapping(address => mapping(address => uint256)) public expirations;
constructor(
string memory _name,
string memory _symbol,
uint8 _decimals
) ERC20Detailed(_name, _symbol, _decimals) public {
DOMAIN_SEPARATOR = keccak256(abi.encode(
keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
keccak256(bytes(_name)),
keccak256(bytes(version)),
1, // Chain ID for Ethereum Mainnet
address(this)
));
}
/// @dev transferFrom in this contract works in a slightly different form than the generic
/// transferFrom function. This contract allows for "unlimited approval".
/// Should the user approve an address for the maximum uint256 value,
/// then that address will have unlimited approval until told otherwise.
/// @param _sender The address of the sender.
/// @param _recipient The address of the recipient.
/// @param _amount The value to transfer.
/// @return Success status.
function transferFrom(address _sender, address _recipient, uint256 _amount) public returns (bool) {
_transfer(_sender, _recipient, _amount);
if (_sender != msg.sender) {
uint256 allowedAmount = allowance(_sender, msg.sender);
if (allowedAmount != uint256(-1)) {
// If allowance is limited, adjust it.
// In this case `transferFrom` works like the generic
_approve(_sender, msg.sender, allowedAmount.sub(_amount));
} else {
// If allowance is unlimited by `permit`, `approve`, or `increaseAllowance`
// function, don't adjust it. But the expiration date must be empty or in the future
require(
expirations[_sender][msg.sender] == 0 || expirations[_sender][msg.sender] >= _now(),
"expiry is in the past"
);
}
} else {
// If `_sender` is `msg.sender`,
// the function works just like `transfer()`
}
return true;
}
/// @dev An alias for `transfer` function.
/// @param _to The address of the recipient.
/// @param _amount The value to transfer.
function push(address _to, uint256 _amount) public {
transferFrom(msg.sender, _to, _amount);
}
/// @dev Makes a request to transfer the specified amount
/// from the specified address to the caller's address.
/// @param _from The address of the holder.
/// @param _amount The value to transfer.
function pull(address _from, uint256 _amount) public {
transferFrom(_from, msg.sender, _amount);
}
/// @dev An alias for `transferFrom` function.
/// @param _from The address of the sender.
/// @param _to The address of the recipient.
/// @param _amount The value to transfer.
function move(address _from, address _to, uint256 _amount) public {
transferFrom(_from, _to, _amount);
}
/// @dev Allows to spend holder's unlimited amount by the specified spender.
/// The function can be called by anyone, but requires having allowance parameters
/// signed by the holder according to EIP712.
/// @param _holder The holder's address.
/// @param _spender The spender's address.
/// @param _nonce The nonce taken from `nonces(_holder)` public getter.
/// @param _expiry The allowance expiration date (unix timestamp in UTC).
/// Can be zero for no expiration. Forced to zero if `_allowed` is `false`.
/// @param _allowed True to enable unlimited allowance for the spender by the holder. False to disable.
/// @param _v A final byte of signature (ECDSA component).
/// @param _r The first 32 bytes of signature (ECDSA component).
/// @param _s The second 32 bytes of signature (ECDSA component).
function permit(
address _holder,
address _spender,
uint256 _nonce,
uint256 _expiry,
bool _allowed,
uint8 _v,
bytes32 _r,
bytes32 _s
) external {
require(_expiry == 0 || _now() <= _expiry, "invalid expiry");
bytes32 digest = keccak256(abi.encodePacked(
"\x19\x01",
DOMAIN_SEPARATOR,
keccak256(abi.encode(
PERMIT_TYPEHASH,
_holder,
_spender,
_nonce,
_expiry,
_allowed
))
));
require(_holder == ecrecover(digest, _v, _r, _s), "invalid signature or parameters");
require(_nonce == nonces[_holder]++, "invalid nonce");
uint256 amount = _allowed ? uint256(-1) : 0;
_approve(_holder, _spender, amount);
expirations[_holder][_spender] = _allowed ? _expiry : 0;
}
function _now() internal view returns(uint256) {
return now;
}
}
// This is a base staking token ERC677 contract for Ethereum Mainnet side
// which is derived by the child ERC677MultiBridgeToken contract.
contract ERC677BridgeToken is Ownable, ERC20Permittable {
using SafeERC20 for ERC20;
using Address for address;
/// @dev Distribution contract address.
address public distributionAddress;
/// @dev The PrivateOffering contract address.
address public privateOfferingDistributionAddress;
/// @dev The AdvisorsReward contract address.
address public advisorsRewardDistributionAddress;
/// @dev Mint event.
/// @param to To address.
/// @param amount Minted value.
event Mint(address indexed to, uint256 amount);
/// @dev Modified Transfer event with custom data.
/// @param from From address.
/// @param to To address.
/// @param value Transferred value.
/// @param data Custom data to call after transfer.
event Transfer(address indexed from, address indexed to, uint256 value, bytes data);
/// @dev Emits if custom call after transfer fails.
/// @param from From address.
/// @param to To address.
/// @param value Transferred value.
event ContractFallbackCallFailed(address from, address to, uint256 value);
/// @dev Checks that the recipient address is valid.
/// @param _recipient Recipient address.
modifier validRecipient(address _recipient) {
require(_recipient != address(0) && _recipient != address(this), "not a valid recipient");
_;
}
/// @dev Reverts if called by any account other than the bridge.
modifier onlyBridge() {
require(isBridge(msg.sender), "caller is not the bridge");
_;
}
/// @dev Creates a token and mints the whole supply for the Distribution contract.
/// @param _name Token name.
/// @param _symbol Token symbol.
/// @param _distributionAddress The address of the deployed Distribution contract.
/// @param _privateOfferingDistributionAddress The address of the PrivateOffering contract.
/// @param _advisorsRewardDistributionAddress The address of the AdvisorsReward contract.
constructor(
string memory _name,
string memory _symbol,
address _distributionAddress,
address _privateOfferingDistributionAddress,
address _advisorsRewardDistributionAddress
) ERC20Permittable(_name, _symbol, 18) public {
require(
_distributionAddress.isContract() &&
_privateOfferingDistributionAddress.isContract() &&
_advisorsRewardDistributionAddress.isContract(),
"not a contract address"
);
uint256 supply = IDistribution(_distributionAddress).supply();
require(supply > 0, "the supply must be more than 0");
_mint(_distributionAddress, supply);
distributionAddress = _distributionAddress;
privateOfferingDistributionAddress = _privateOfferingDistributionAddress;
advisorsRewardDistributionAddress = _advisorsRewardDistributionAddress;
emit Mint(_distributionAddress, supply);
}
/// @dev Checks if given address is included into bridge contracts list.
/// Implemented by a child contract.
/// @param _address Bridge contract address.
/// @return bool true, if given address is a known bridge contract.
function isBridge(address _address) public view returns (bool);
/// @dev Extends transfer method with callback.
/// @param _to The address of the recipient.
/// @param _value The value to transfer.
/// @param _data Custom data.
/// @return Success status.
function transferAndCall(
address _to,
uint256 _value,
bytes calldata _data
) external validRecipient(_to) returns (bool) {
_superTransfer(_to, _value);
emit Transfer(msg.sender, _to, _value, _data);
if (_to.isContract()) {
require(_contractFallback(msg.sender, _to, _value, _data), "contract call failed");
}
return true;
}
/// @dev Extends transfer method with event when the callback failed.
/// @param _to The address of the recipient.
/// @param _value The value to transfer.
/// @return Success status.
function transfer(address _to, uint256 _value) public returns (bool) {
_superTransfer(_to, _value);
_callAfterTransfer(msg.sender, _to, _value);
return true;
}
/// @dev This is a copy of `transfer` function which can only be called by distribution contracts.
/// Made to get rid of `onTokenTransfer` calling to save gas when distributing tokens.
/// @param _to The address of the recipient.
/// @param _value The value to transfer.
/// @return Success status.
function transferDistribution(address _to, uint256 _value) public returns (bool) {
require(
msg.sender == distributionAddress ||
msg.sender == privateOfferingDistributionAddress ||
msg.sender == advisorsRewardDistributionAddress,
"wrong sender"
);
_superTransfer(_to, _value);
return true;
}
/// @dev Extends transferFrom method with event when the callback failed.
/// @param _from The address of the sender.
/// @param _to The address of the recipient.
/// @param _value The value to transfer.
/// @return Success status.
function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
_superTransferFrom(_from, _to, _value);
_callAfterTransfer(_from, _to, _value);
return true;
}
/// @dev If someone sent eth/tokens to the contract mistakenly then the owner can send them back.
/// @param _token The token address to transfer.
/// @param _to The address of the recipient.
function claimTokens(address _token, address payable _to) public onlyOwner validRecipient(_to) {
if (_token == address(0)) {
uint256 value = address(this).balance;
if (!_to.send(value)) { // solium-disable-line security/no-send
// We use the `Sacrifice` trick to be sure the coins can be 100% sent to the receiver.
// Otherwise, if the receiver is a contract which has a revert in its fallback function,
// the sending will fail.
(new Sacrifice).value(value)(_to);
}
} else {
ERC20 token = ERC20(_token);
uint256 balance = token.balanceOf(address(this));
token.safeTransfer(_to, balance);
}
}
/// @dev Creates `amount` tokens and assigns them to `account`, increasing
/// the total supply. Emits a `Transfer` event with `from` set to the zero address.
/// Can only be called by a bridge contract which address is set with `addBridge`.
/// @param _account The address to mint tokens for. Cannot be zero address.
/// @param _amount The amount of tokens to mint.
function mint(address _account, uint256 _amount) external onlyBridge returns(bool) {
_mint(_account, _amount);
emit Mint(_account, _amount);
return true;
}
/// @dev The removed implementation of the ownership renouncing.
function renounceOwnership() public onlyOwner {
revert("not implemented");
}
/// @dev Calls transfer method and reverts if it fails.
/// @param _to The address of the recipient.
/// @param _value The value to transfer.
function _superTransfer(address _to, uint256 _value) internal {
bool success;
if (
msg.sender == distributionAddress ||
msg.sender == privateOfferingDistributionAddress ||
msg.sender == advisorsRewardDistributionAddress
) {
// Allow sending tokens to `address(0)` by
// Distribution, PrivateOffering, or AdvisorsReward contract
_balances[msg.sender] = _balances[msg.sender].sub(_value);
_balances[_to] = _balances[_to].add(_value);
emit Transfer(msg.sender, _to, _value);
success = true;
} else {
success = super.transfer(_to, _value);
}
require(success, "transfer failed");
}
/// @dev Calls transferFrom method and reverts if it fails.
/// @param _from The address of the sender.
/// @param _to The address of the recipient.
/// @param _value The value to transfer.
function _superTransferFrom(address _from, address _to, uint256 _value) internal {
bool success = super.transferFrom(_from, _to, _value);
require(success, "transfer failed");
}
/// @dev Emits an event when the callback failed.
/// @param _from The address of the sender.
/// @param _to The address of the recipient.
/// @param _value The transferred value.
function _callAfterTransfer(address _from, address _to, uint256 _value) internal {
if (_to.isContract() && !_contractFallback(_from, _to, _value, new bytes(0))) {
require(!isBridge(_to), "you can't transfer to bridge contract");
require(_to != distributionAddress, "you can't transfer to Distribution contract");
require(_to != privateOfferingDistributionAddress, "you can't transfer to PrivateOffering contract");
require(_to != advisorsRewardDistributionAddress, "you can't transfer to AdvisorsReward contract");
emit ContractFallbackCallFailed(_from, _to, _value);
}
}
/// @dev Makes a callback after the transfer of tokens.
/// @param _from The address of the sender.
/// @param _to The address of the recipient.
/// @param _value The transferred value.
/// @param _data Custom data.
/// @return Success status.
function _contractFallback(
address _from,
address _to,
uint256 _value,
bytes memory _data
) private returns (bool) {
string memory signature = "onTokenTransfer(address,uint256,bytes)";
// solium-disable-next-line security/no-low-level-calls
(bool success, ) = _to.call(abi.encodeWithSignature(signature, _from, _value, _data));
return success;
}
}
/**
* @title ERC677MultiBridgeToken
* @dev This contract extends ERC677BridgeToken to support several bridges simultaneously.
*/
contract ERC677MultiBridgeToken is IERC677MultiBridgeToken, ERC677BridgeToken {
address public constant F_ADDR = 0xFFfFfFffFFfffFFfFFfFFFFFffFFFffffFfFFFfF;
uint256 internal constant MAX_BRIDGES = 50;
mapping(address => address) public bridgePointers;
uint256 public bridgeCount;
event BridgeAdded(address indexed bridge);
event BridgeRemoved(address indexed bridge);
constructor(
string memory _name,
string memory _symbol,
address _distributionAddress,
address _privateOfferingDistributionAddress,
address _advisorsRewardDistributionAddress
) public ERC677BridgeToken(
_name,
_symbol,
_distributionAddress,
_privateOfferingDistributionAddress,
_advisorsRewardDistributionAddress
) {
bridgePointers[F_ADDR] = F_ADDR; // empty bridge contracts list
}
/// @dev Adds one more bridge contract into the list.
/// @param _bridge Bridge contract address.
function addBridge(address _bridge) external onlyOwner {
require(bridgeCount < MAX_BRIDGES, "can't add one more bridge due to a limit");
require(_bridge.isContract(), "not a contract address");
require(!isBridge(_bridge), "bridge already exists");
address firstBridge = bridgePointers[F_ADDR];
require(firstBridge != address(0), "first bridge is zero address");
bridgePointers[F_ADDR] = _bridge;
bridgePointers[_bridge] = firstBridge;
bridgeCount = bridgeCount.add(1);
emit BridgeAdded(_bridge);
}
/// @dev Removes one existing bridge contract from the list.
/// @param _bridge Bridge contract address.
function removeBridge(address _bridge) external onlyOwner {
require(isBridge(_bridge), "bridge isn't existed");
address nextBridge = bridgePointers[_bridge];
address index = F_ADDR;
address next = bridgePointers[index];
require(next != address(0), "zero address found");
while (next != _bridge) {
index = next;
next = bridgePointers[index];
require(next != F_ADDR && next != address(0), "invalid address found");
}
bridgePointers[index] = nextBridge;
delete bridgePointers[_bridge];
bridgeCount = bridgeCount.sub(1);
emit BridgeRemoved(_bridge);
}
/// @dev Returns all recorded bridge contract addresses.
/// @return address[] Bridge contract addresses.
function bridgeList() external view returns (address[] memory) {
address[] memory list = new address[](bridgeCount);
uint256 counter = 0;
address nextBridge = bridgePointers[F_ADDR];
require(nextBridge != address(0), "zero address found");
while (nextBridge != F_ADDR) {
list[counter] = nextBridge;
nextBridge = bridgePointers[nextBridge];
counter++;
require(nextBridge != address(0), "zero address found");
}
return list;
}
/// @dev Checks if given address is included into bridge contracts list.
/// @param _address Bridge contract address.
/// @return bool true, if given address is a known bridge contract.
function isBridge(address _address) public view returns (bool) {
return _address != F_ADDR && bridgePointers[_address] != address(0);
}
}