/**
* Source Code first verified at https://etherscan.io on Monday, April 15, 2019
(UTC) */
pragma solidity 0.5.6;
/**
* Utility library of inline functions on addresses
*/
library Address {
/**
* Returns whether the target address is a contract
* @dev This function will return false if invoked during the constructor of a contract,
* as the code is not actually created until after the constructor finishes.
* @param account address of the account to check
* @return whether the target address is a contract
*/
function isContract(address account) internal view returns (bool) {
uint256 size;
// XXX Currently there is no better way to check if there is a contract in an address
// than to check the size of the code at that address.
// See https://ethereum.stackexchange.com/a/14016/36603
// for more details about how this works.
// TODO Check this again before the Serenity release, because all addresses will be
// contracts then.
// solhint-disable-next-line no-inline-assembly
assembly { size := extcodesize(account) }
return size > 0;
}
}
/**
* @title SafeMath
* @dev Unsigned math operations with safety checks that revert on error
*/
library SafeMath {
/**
* @dev Multiplies two unsigned integers, reverts on 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);
return c;
}
/**
* @dev Integer division of two unsigned integers truncating the quotient, reverts on division by zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// Solidity only automatically asserts when dividing by 0
require(b > 0);
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Subtracts two unsigned integers, reverts on overflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a);
uint256 c = a - b;
return c;
}
/**
* @dev Adds two unsigned integers, reverts on overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a);
return c;
}
/**
* @dev Divides two unsigned integers and returns the remainder (unsigned integer modulo),
* reverts when dividing by zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
require(b != 0);
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'
require((value == 0) || (token.allowance(address(this), spender) == 0));
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 equal true).
* @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.
require(address(token).isContract());
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = address(token).call(data);
require(success);
if (returndata.length > 0) { // Return data is optional
require(abi.decode(returndata, (bool)));
}
}
}
/**
* @title Ownable
* @dev The Ownable contract has an owner address, and provides basic authorization control
* functions, this simplifies the implementation of "user permissions".
*/
contract Ownable {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev The Ownable constructor sets the original `owner` of the contract to the sender
* account.
*/
constructor () internal {
_owner = msg.sender;
emit OwnershipTransferred(address(0), _owner);
}
/**
* @return the address of the owner.
*/
function owner() public view returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(isOwner());
_;
}
/**
* @return true if `msg.sender` is the owner of the contract.
*/
function isOwner() public view returns (bool) {
return msg.sender == _owner;
}
/**
* @dev Allows the current owner to relinquish control of the contract.
* It will not be possible to call the functions with the `onlyOwner`
* modifier anymore.
* @notice 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 Allows the current owner to transfer control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/
function transferOwnership(address newOwner) public onlyOwner {
_transferOwnership(newOwner);
}
/**
* @dev Transfers control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/
function _transferOwnership(address newOwner) internal {
require(newOwner != address(0));
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
/**
* @title ERC20 interface
* @dev see https://eips.ethereum.org/EIPS/eip-20
*/
interface IERC20 {
function transfer(address to, uint256 value) external returns (bool);
function approve(address spender, uint256 value) external returns (bool);
function transferFrom(address from, address to, uint256 value) external returns (bool);
function totalSupply() external view returns (uint256);
function balanceOf(address who) external view returns (uint256);
function allowance(address owner, address spender) external view returns (uint256);
function transferOwnership(address newOwner) external;
event Transfer(address indexed from, address indexed to, uint256 value);
event Approval(address indexed owner, address indexed spender, uint256 value);
}
/**
* @title Standard ERC20 token
*
* @dev Implementation of the basic standard token.
* https://eips.ethereum.org/EIPS/eip-20
* Originally based on code by FirstBlood:
* https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
*
* This implementation emits additional Approval events, allowing applications to reconstruct the allowance status for
* all accounts just by listening to said events. Note that this isn't required by the specification, and other
* compliant implementations may not do it.
*/
contract ERC20 is IERC20 {
using SafeMath for uint256;
mapping (address => uint256) private _balances;
mapping (address => mapping (address => uint256)) private _allowed;
uint256 private _totalSupply;
/**
* @dev Total number of tokens in existence
*/
function totalSupply() public view returns (uint256) {
return _totalSupply;
}
/**
* @dev Gets the balance of the specified address.
* @param owner The address to query the balance of.
* @return A uint256 representing the amount owned by the passed address.
*/
function balanceOf(address owner) public view returns (uint256) {
return _balances[owner];
}
/**
* @dev Function to check the amount of tokens that an owner allowed to a spender.
* @param owner address The address which owns the funds.
* @param spender address The address which will spend the funds.
* @return A uint256 specifying the amount of tokens still available for the spender.
*/
function allowance(address owner, address spender) public view returns (uint256) {
return _allowed[owner][spender];
}
/**
* @dev Transfer token to a specified address
* @param to The address to transfer to.
* @param value The amount to be transferred.
*/
function transfer(address to, uint256 value) public returns (bool) {
_transfer(msg.sender, to, value);
return true;
}
/**
* @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
* 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
* @param spender The address which will spend the funds.
* @param value The amount of tokens to be spent.
*/
function approve(address spender, uint256 value) public returns (bool) {
_approve(msg.sender, spender, value);
return true;
}
/**
* @dev Transfer tokens from one address to another.
* Note that while this function emits an Approval event, this is not required as per the specification,
* and other compliant implementations may not emit the event.
* @param from address The address which you want to send tokens from
* @param to address The address which you want to transfer to
* @param value uint256 the amount of tokens to be transferred
*/
function transferFrom(address from, address to, uint256 value) public returns (bool) {
_transfer(from, to, value);
_approve(from, msg.sender, _allowed[from][msg.sender].sub(value));
return true;
}
/**
* @dev Increase the amount of tokens that an owner allowed to a spender.
* approve should be called when _allowed[msg.sender][spender] == 0. To increment
* allowed value is better to use this function to avoid 2 calls (and wait until
* the first transaction is mined)
* From MonolithDAO Token.sol
* Emits an Approval event.
* @param spender The address which will spend the funds.
* @param addedValue The amount of tokens to increase the allowance by.
*/
function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
_approve(msg.sender, spender, _allowed[msg.sender][spender].add(addedValue));
return true;
}
/**
* @dev Decrease the amount of tokens that an owner allowed to a spender.
* approve should be called when _allowed[msg.sender][spender] == 0. To decrement
* allowed value is better to use this function to avoid 2 calls (and wait until
* the first transaction is mined)
* From MonolithDAO Token.sol
* Emits an Approval event.
* @param spender The address which will spend the funds.
* @param subtractedValue The amount of tokens to decrease the allowance by.
*/
function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
_approve(msg.sender, spender, _allowed[msg.sender][spender].sub(subtractedValue));
return true;
}
/**
* @dev Transfer token for a specified addresses
* @param from The address to transfer from.
* @param to The address to transfer to.
* @param value The amount to be transferred.
*/
function _transfer(address from, address to, uint256 value) internal {
require(to != address(0));
_balances[from] = _balances[from].sub(value);
_balances[to] = _balances[to].add(value);
emit Transfer(from, to, value);
}
/**
* @dev Internal function that mints an amount of the token and assigns it to
* an account. This encapsulates the modification of balances such that the
* proper events are emitted.
* @param account The account that will receive the created tokens.
* @param value The amount that will be created.
*/
function _mint(address account, uint256 value) internal {
require(account != address(0));
_totalSupply = _totalSupply.add(value);
_balances[account] = _balances[account].add(value);
emit Transfer(address(0), account, value);
}
/**
* @dev Internal function that burns an amount of the token of a given
* account.
* @param account The account whose tokens will be burnt.
* @param value The amount that will be burnt.
*/
function _burn(address account, uint256 value) internal {
require(account != address(0));
_totalSupply = _totalSupply.sub(value);
_balances[account] = _balances[account].sub(value);
emit Transfer(account, address(0), value);
}
/**
* @dev Approve an address to spend another addresses' tokens.
* @param owner The address that owns the tokens.
* @param spender The address that will spend the tokens.
* @param value The number of tokens that can be spent.
*/
function _approve(address owner, address spender, uint256 value) internal {
require(spender != address(0));
require(owner != address(0));
_allowed[owner][spender] = value;
emit Approval(owner, spender, value);
}
/**
* @dev Internal function that burns an amount of the token of a given
* account, deducting from the sender's allowance for said account. Uses the
* internal burn function.
* Emits an Approval event (reflecting the reduced allowance).
* @param account The account whose tokens will be burnt.
* @param value The amount that will be burnt.
*/
function _burnFrom(address account, uint256 value) internal {
_burn(account, value);
_approve(account, msg.sender, _allowed[account][msg.sender].sub(value));
}
}
/**
* @title Burnable Token
* @dev Token that can be irreversibly burned (destroyed).
*/
contract ERC20Burnable is ERC20 {
/**
* @dev Burns a specific amount of tokens.
* @param value The amount of token to be burned.
*/
function burn(uint256 value) public {
_burn(msg.sender, value);
}
/**
* @dev Burns a specific amount of tokens from the target address and decrements allowance
* @param from address The account whose tokens will be burned.
* @param value uint256 The amount of token to be burned.
*/
function burnFrom(address from, uint256 value) public {
_burnFrom(from, value);
}
}
/**
* @title Pausable
* @dev Base contract which allows children to implement an emergency stop mechanism.
*/
contract Pausable is Ownable {
event Paused(address account);
event Unpaused(address account);
bool private _paused;
constructor () internal {
_paused = false;
}
/**
* @return true if the contract is paused, false otherwise.
*/
function paused() public view returns (bool) {
return _paused;
}
/**
* @dev Modifier to make a function callable only when the contract is not paused.
*/
modifier whenNotPaused() {
require(!_paused);
_;
}
/**
* @dev Modifier to make a function callable only when the contract is paused.
*/
modifier whenPaused() {
require(_paused);
_;
}
/**
* @dev called by the owner to pause, triggers stopped state
*/
function pause() public onlyOwner whenNotPaused {
_paused = true;
emit Paused(msg.sender);
}
/**
* @dev called by the owner to unpause, returns to normal state
*/
function unpause() public onlyOwner whenPaused {
_paused = false;
emit Unpaused(msg.sender);
}
}
/**
* @title Pausable token
* @dev ERC20 modified with pausable transfers.
*/
contract ERC20Pausable is ERC20, Pausable {
function transfer(address to, uint256 value) public whenNotPaused returns (bool) {
return super.transfer(to, value);
}
function transferFrom(address from, address to, uint256 value) public whenNotPaused returns (bool) {
return super.transferFrom(from, to, value);
}
function approve(address spender, uint256 value) public whenNotPaused returns (bool) {
return super.approve(spender, value);
}
function increaseAllowance(address spender, uint addedValue) public whenNotPaused returns (bool success) {
return super.increaseAllowance(spender, addedValue);
}
function decreaseAllowance(address spender, uint subtractedValue) public whenNotPaused returns (bool success) {
return super.decreaseAllowance(spender, subtractedValue);
}
}
/**
* @title FreezableToken
*/
contract ERC20Freezable is ERC20, Ownable {
mapping(address => bool) public frozenAccounts;
event FrozenFunds(address target, bool frozen);
function freezeAccount(address target) public onlyOwner {
frozenAccounts[target] = true;
emit FrozenFunds(target, true);
}
function unFreezeAccount(address target) public onlyOwner {
frozenAccounts[target] = false;
emit FrozenFunds(target, false);
}
function frozen(address _target) view public returns(bool) {
return frozenAccounts[_target];
}
// @dev Limit token transfer if _sender is frozen.
modifier canTransfer(address _sender) {
require(!frozenAccounts[_sender]);
_;
}
function transfer(address _to, uint256 _value) public canTransfer(msg.sender) returns(bool success) {
// Call StandardToken.transfer()
return super.transfer(_to, _value);
}
function transferFrom(address _from, address _to, uint256 _value) public canTransfer(_from) returns(bool success) {
// Call StandardToken.transferForm()
return super.transferFrom(_from, _to, _value);
}
}
/**
* @title AirSaveTravelToken
*/
contract AirSaveTravelTokens is ERC20Freezable, ERC20Pausable, ERC20Burnable {
string private constant _name = "AirSaveTravel Tokens";
string private constant _symbol = "ASTC";
uint8 private constant _decimals = 18;
/**
* @dev AirSaveTravelToken constructor method
*/
constructor () public {
//sending 35 mln tokens to the main wallet
//the number of tokens is fixed and cannot be minted in future
_mint(msg.sender, 35000000 * 1 ether);
}
/**
* @return the name of the token.
*/
function name() public pure returns (string memory) {
return _name;
}
/**
* @return the symbol of the token.
*/
function symbol() public pure returns (string memory) {
return _symbol;
}
/**
* @return the number of decimals of the token.
*/
function decimals() public pure returns (uint8) {
return _decimals;
}
}
/**
* @title Helps contracts guard against reentrancy attacks.
* @author Remco Bloemen <[email protected]π.com>, Eenae <[email protected]>
* @dev If you mark a function `nonReentrant`, you should also
* mark it `external`.
*/
contract ReentrancyGuard {
/// @dev counter to allow mutex lock with only one SSTORE operation
uint256 private _guardCounter;
constructor () internal {
// The counter starts at one to prevent changing it from zero to a non-zero
// value, which is a more expensive operation.
_guardCounter = 1;
}
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* Calling a `nonReentrant` function from another `nonReentrant`
* function is not supported. It is possible to prevent this from happening
* by making the `nonReentrant` function external, and make it call a
* `private` function that does the actual work.
*/
modifier nonReentrant() {
_guardCounter += 1;
uint256 localCounter = _guardCounter;
_;
require(localCounter == _guardCounter);
}
}
/**
* @title Crowdsale
* @dev Crowdsale is a base contract for managing a token crowdsale,
* allowing investors to purchase tokens with ether. This contract implements
* such functionality in its most fundamental form and can be extended to provide additional
* functionality and/or custom behavior.
* The external interface represents the basic interface for purchasing tokens, and conform
* the base architecture for crowdsales. They are *not* intended to be modified / overridden.
* The internal interface conforms the extensible and modifiable surface of crowdsales. Override
* the methods to add functionality. Consider using 'super' where appropriate to concatenate
* behavior.
*/
contract Crowdsale is ReentrancyGuard {
using SafeMath for uint256;
using SafeERC20 for IERC20;
// The token being sold
IERC20 private _token;
// Address where funds are collected
address payable private _wallet;
// 1 ETH = 750 ASTC
uint256 private _rate = 750;
// Amount of wei raised
uint256 private _weiRaised;
/**
* Event for token purchase logging
* @param purchaser who paid for the tokens
* @param beneficiary who got the tokens
* @param value weis paid for purchase
* @param amount amount of tokens purchased
*/
event TokensPurchased(address indexed purchaser, address indexed beneficiary, uint256 value, uint256 amount);
constructor () public {
_wallet = msg.sender;
_token = IERC20(new AirSaveTravelTokens());
_token.safeTransfer(_wallet, 29750000000 * 1 finney); //29,75 mln tokens to owner
_token.transferOwnership(_wallet);
}
/**
* @dev fallback function ***DO NOT OVERRIDE***
* Note that other contracts will transfer fund with a base gas stipend
* of 2300, which is not enough to call buyTokens. Consider calling
* buyTokens directly when purchasing tokens from a contract.
*/
function () external payable {
buyTokens(msg.sender);
}
/**
* @return the token being sold.
*/
function token() public view returns (IERC20) {
return _token;
}
/**
* @return the address where funds are collected.
*/
function wallet() public view returns (address payable) {
return _wallet;
}
/**
* @return the number of token units a buyer gets per wei.
*/
function rate() public view returns (uint256) {
return _rate;
}
/**
* @return the amount of wei raised.
*/
function weiRaised() public view returns (uint256) {
return _weiRaised;
}
/**
* @dev low level token purchase ***DO NOT OVERRIDE***
* This function has a non-reentrancy guard, so it shouldn't be called by
* another `nonReentrant` function.
* @param beneficiary Recipient of the token purchase
*/
function buyTokens(address beneficiary) public nonReentrant payable {
uint256 weiAmount = msg.value;
_preValidatePurchase(beneficiary, weiAmount);
// calculate token amount to be created
uint256 tokens = _getTokenAmount(weiAmount);
require(_token.balanceOf(address(this)) >= tokens, "buyTokens:the contract has not enough token balance for purchasing");
// update state
_weiRaised = _weiRaised.add(weiAmount);
_processPurchase(beneficiary, tokens);
emit TokensPurchased(msg.sender, beneficiary, weiAmount, tokens);
_forwardFunds();
}
function changeWallet(address payable newWallet) external {
require(newWallet != address(0), "changeWallet: invalid wallet address");
require(msg.sender == _wallet, "changeWallet: only current wallet can change it");
_wallet = newWallet;
}
/**
* @dev Validation of an incoming purchase. Use require statements to revert state when conditions are not met.
* Use `super` in contracts that inherit from Crowdsale to extend their validations.
* Example from CappedCrowdsale.sol's _preValidatePurchase method:
* super._preValidatePurchase(beneficiary, weiAmount);
* require(weiRaised().add(weiAmount) <= cap);
* @param beneficiary Address performing the token purchase
* @param weiAmount Value in wei involved in the purchase
*/
function _preValidatePurchase(address beneficiary, uint256 weiAmount) internal view {
require(beneficiary != address(0));
require(weiAmount != 0);
}
/**
* @dev Source of tokens. Override this method to modify the way in which the crowdsale ultimately gets and sends
* its tokens.
* @param beneficiary Address performing the token purchase
* @param tokenAmount Number of tokens to be emitted
*/
function _deliverTokens(address beneficiary, uint256 tokenAmount) internal {
_token.safeTransfer(beneficiary, tokenAmount);
}
/**
* @dev Executed when a purchase has been validated and is ready to be executed. Doesn't necessarily emit/send
* tokens.
* @param beneficiary Address receiving the tokens
* @param tokenAmount Number of tokens to be purchased
*/
function _processPurchase(address beneficiary, uint256 tokenAmount) internal {
_deliverTokens(beneficiary, tokenAmount);
}
/**
* @dev Override to extend the way in which ether is converted to tokens.
* @param weiAmount Value in wei to be converted into tokens
* @return Number of tokens that can be purchased with the specified _weiAmount
*/
function _getTokenAmount(uint256 weiAmount) internal view returns (uint256) {
return weiAmount.mul(_rate);
}
/**
* @dev Determines how ETH is stored/forwarded on purchases.
*/
function _forwardFunds() internal {
_wallet.transfer(msg.value);
}
}
/**
* @title Roles
* @dev Library for managing addresses assigned to a Role.
*/
library Roles {
struct Role {
mapping (address => bool) bearer;
}
/**
* @dev give an account access to this role
*/
function add(Role storage role, address account) internal {
require(account != address(0));
require(!has(role, account));
role.bearer[account] = true;
}
/**
* @dev remove an account's access to this role
*/
function remove(Role storage role, address account) internal {
require(account != address(0));
require(has(role, account));
role.bearer[account] = false;
}
/**
* @dev check if an account has this role
* @return bool
*/
function has(Role storage role, address account) internal view returns (bool) {
require(account != address(0));
return role.bearer[account];
}
}
/**
* @title WhitelistAdminRole
* @dev WhitelistAdmins are responsible for assigning and removing Whitelisted accounts.
*/
contract WhitelistAdminRole {
using Roles for Roles.Role;
event WhitelistAdminAdded(address indexed account);
event WhitelistAdminRemoved(address indexed account);
Roles.Role private _whitelistAdmins;
constructor () internal {
_addWhitelistAdmin(msg.sender);
}
modifier onlyWhitelistAdmin() {
require(isWhitelistAdmin(msg.sender));
_;
}
function isWhitelistAdmin(address account) public view returns (bool) {
return _whitelistAdmins.has(account);
}
function addWhitelistAdmin(address account) public onlyWhitelistAdmin {
_addWhitelistAdmin(account);
}
function renounceWhitelistAdmin() public {
_removeWhitelistAdmin(msg.sender);
}
function _addWhitelistAdmin(address account) internal {
_whitelistAdmins.add(account);
emit WhitelistAdminAdded(account);
}
function _removeWhitelistAdmin(address account) internal {
_whitelistAdmins.remove(account);
emit WhitelistAdminRemoved(account);
}
}
/**
* @title WhitelistedRole
* @dev Whitelisted accounts have been approved by a WhitelistAdmin to perform certain actions (e.g. participate in a
* crowdsale). This role is special in that the only accounts that can add it are WhitelistAdmins (who can also remove
* it), and not Whitelisteds themselves.
*/
contract WhitelistedRole is WhitelistAdminRole {
using Roles for Roles.Role;
event WhitelistedAdded(address indexed account);
event WhitelistedRemoved(address indexed account);
Roles.Role private _whitelisteds;
modifier onlyWhitelisted() {
require(isWhitelisted(msg.sender));
_;
}
function isWhitelisted(address account) public view returns (bool) {
return _whitelisteds.has(account);
}
function addWhitelisted(address account) public onlyWhitelistAdmin {
_addWhitelisted(account);
}
function removeWhitelisted(address account) public onlyWhitelistAdmin {
_removeWhitelisted(account);
}
function renounceWhitelisted() public {
_removeWhitelisted(msg.sender);
}
function _addWhitelisted(address account) internal {
_whitelisteds.add(account);
emit WhitelistedAdded(account);
}
function _removeWhitelisted(address account) internal {
_whitelisteds.remove(account);
emit WhitelistedRemoved(account);
}
}
/**
* @title WhitelistCrowdsale
* @dev Crowdsale in which only whitelisted users can contribute.
*/
contract WhitelistCrowdsale is WhitelistedRole, Crowdsale {
/**
* @dev Extend parent behavior requiring beneficiary to be whitelisted. Note that no
* restriction is imposed on the account sending the transaction.
* @param _beneficiary Token beneficiary
* @param _weiAmount Amount of wei contributed
*/
function _preValidatePurchase(address _beneficiary, uint256 _weiAmount) internal view {
require(isWhitelisted(_beneficiary));
super._preValidatePurchase(_beneficiary, _weiAmount);
}
}