Contract Source Code:
File 1 of 1 : WellToken
pragma solidity ^0.4.24;
/**
* @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;
assert(c / a == b);
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) {
assert(b <= a);
return a - b;
}
/**
* @dev Adds two numbers, throws on overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256 c) {
c = a + b;
assert(c >= a);
return c;
}
}
/**
* @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 public owner;
event OwnershipRenounced(address indexed previousOwner);
event OwnershipTransferred(
address indexed previousOwner,
address indexed newOwner
);
/**
* @dev The Ownable constructor sets the original `owner` of the contract to the sender
* account.
*/
constructor() public {
owner = msg.sender;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(msg.sender == owner);
_;
}
/**
* @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 ERC20Basic
* @dev Simpler version of ERC20 interface
* @dev see https://github.com/ethereum/EIPs/issues/179
*/
contract ERC20Basic {
function totalSupply() public view returns (uint256);
function balanceOf(address who) public view returns (uint256);
function transfer(address to, uint256 value) public returns (bool);
event Transfer(address indexed from, address indexed to, uint256 value);
}
/**
* @title ERC20 interface
* @dev see https://github.com/ethereum/EIPs/issues/20
*/
contract ERC20 is ERC20Basic {
function allowance(address owner, address spender)
public view returns (uint256);
function transferFrom(address from, address to, uint256 value)
public returns (bool);
function approve(address spender, uint256 value) public returns (bool);
event Approval(
address indexed owner,
address indexed spender,
uint256 value
);
}
/**
* @title Basic token
* @dev Basic version of StandardToken, with no allowances.
*/
contract BasicToken is ERC20Basic {
using SafeMath for uint256;
mapping(address => uint256) balances;
uint256 totalSupply_;
/**
* @dev Total number of tokens in existence
*/
function totalSupply() public view returns (uint256) {
return totalSupply_;
}
/**
* @dev Transfer token for 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) {
require(_to != address(0));
require(_value <= balances[msg.sender]);
balances[msg.sender] = balances[msg.sender].sub(_value);
balances[_to] = balances[_to].add(_value);
emit Transfer(msg.sender, _to, _value);
return true;
}
/**
* @dev Gets the balance of the specified address.
* @param _owner The address to query the the balance of.
* @return An uint256 representing the amount owned by the passed address.
*/
function balanceOf(address _owner) public view returns (uint256) {
return balances[_owner];
}
}
/**
* @title Standard ERC20 token
*
* @dev Implementation of the basic standard token.
* @dev https://github.com/ethereum/EIPs/issues/20
* @dev Based on code by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
*/
contract StandardToken is ERC20, BasicToken {
mapping (address => mapping (address => uint256)) internal allowed;
/**
* @dev Transfer tokens from one address to another
* @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)
{
require(_to != address(0));
require(_value <= balances[_from]);
require(_value <= allowed[_from][msg.sender]);
balances[_from] = balances[_from].sub(_value);
balances[_to] = balances[_to].add(_value);
allowed[_from][msg.sender] = allowed[_from][msg.sender].sub(_value);
emit Transfer(_from, _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) {
allowed[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
return true;
}
/**
* @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 Increase the amount of tokens that an owner allowed to a spender.
*
* approve should be called when allowed[_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
* @param _spender The address which will spend the funds.
* @param _addedValue The amount of tokens to increase the allowance by.
*/
function increaseApproval(
address _spender,
uint _addedValue
)
public
returns (bool)
{
allowed[msg.sender][_spender] = (
allowed[msg.sender][_spender].add(_addedValue));
emit Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
return true;
}
/**
* @dev Decrease the amount of tokens that an owner allowed to a spender.
*
* approve should be called when allowed[_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
* @param _spender The address which will spend the funds.
* @param _subtractedValue The amount of tokens to decrease the allowance by.
*/
function decreaseApproval(
address _spender,
uint _subtractedValue
)
public
returns (bool)
{
uint oldValue = allowed[msg.sender][_spender];
if (_subtractedValue > oldValue) {
allowed[msg.sender][_spender] = 0;
} else {
allowed[msg.sender][_spender] = oldValue.sub(_subtractedValue);
}
emit Approval(msg.sender, _spender, allowed[msg.sender][_spender]);
return true;
}
}
/**
* @title Burnable Token
* @dev Token that can be irreversibly burned (destroyed).
*/
contract BurnableToken is BasicToken {
event Burn(address indexed burner, uint256 value);
/**
* @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);
}
function _burn(address _who, uint256 _value) internal {
require(_value <= balances[_who]);
// no need to require value <= totalSupply, since that would imply the
// sender's balance is greater than the totalSupply, which *should* be an assertion failure
balances[_who] = balances[_who].sub(_value);
totalSupply_ = totalSupply_.sub(_value);
emit Burn(_who, _value);
emit Transfer(_who, address(0), _value);
}
}
contract WellToken is StandardToken, BurnableToken, Ownable {
using SafeMath for uint256;
event Mint(address indexed to, uint256 amount);
event Release();
event AddressLocked(address indexed _address, uint256 _time);
event AddressLockedByKYC(address indexed _address);
event KYCVerified(address indexed _address);
event TokensRevertedByKYC(address indexed _address, uint256 _amount);
event SetTechAccount(address indexed _address);
string public constant name = "WELL Token";
string public constant symbol = "WELL";
string public constant standard = "ERC20";
uint256 public constant decimals = 18;
uint256 public constant TOKENS_MAXIMUM_SUPPLY = 1500000000 * (10 ** decimals);
bool public released = false;
address public tokensWallet;
address public mintingOracle;
address public techAccount;
mapping(address => uint) public lockedAddresses;
mapping(address => bool) public verifiedKYCAddresses;
modifier isReleased() {
require(released || msg.sender == tokensWallet || msg.sender == owner || msg.sender == techAccount);
require(lockedAddresses[msg.sender] <= now);
require(verifiedKYCAddresses[msg.sender]);
_;
}
modifier hasAddressLockupPermission() {
require(msg.sender == owner || msg.sender == techAccount);
_;
}
modifier hasMintPermission() {
require(msg.sender == mintingOracle);
_;
}
constructor() public {
owner = 0x6c2386fFf587539484c9d65628df7301A4a7Fc10;
mintingOracle = owner;
tokensWallet = owner;
verifiedKYCAddresses[owner] = true;
techAccount = 0x41D621De050A551F5f0eBb83D1332C75339B61E4;
verifiedKYCAddresses[techAccount] = true;
emit SetTechAccount(techAccount);
balances[tokensWallet] = totalSupply_;
emit Transfer(0x0, tokensWallet, totalSupply_);
}
function lockAddress(address _address, uint256 _time) public hasAddressLockupPermission returns (bool) {
require(_address != owner && _address != tokensWallet && _address != techAccount);
require(balances[_address] == 0 && lockedAddresses[_address] == 0 && _time > now);
lockedAddresses[_address] = _time;
emit AddressLocked(_address, _time);
return true;
}
function lockAddressByKYC(address _address) public hasAddressLockupPermission returns (bool) {
require(released);
require(balances[_address] == 0 && verifiedKYCAddresses[_address]);
verifiedKYCAddresses[_address] = false;
emit AddressLockedByKYC(_address);
return true;
}
function verifyKYC(address _address) public hasAddressLockupPermission returns (bool) {
verifiedKYCAddresses[_address] = true;
emit KYCVerified(_address);
return true;
}
function revertTokensByKYC(address _address) public hasAddressLockupPermission returns (bool) {
require(!verifiedKYCAddresses[_address] && balances[_address] > 0);
uint256 amount = balances[_address];
balances[tokensWallet] = balances[tokensWallet].add(amount);
balances[_address] = 0;
emit Transfer(_address, tokensWallet, amount);
emit TokensRevertedByKYC(_address, amount);
return true;
}
function release() public onlyOwner returns (bool) {
require(!released);
released = true;
emit Release();
return true;
}
function getOwner() public view returns (address) {
return owner;
}
function transfer(address _to, uint256 _value) public isReleased returns (bool) {
if (released) {
verifiedKYCAddresses[_to] = true;
}
return super.transfer(_to, _value);
}
function transferFrom(address _from, address _to, uint256 _value) public isReleased returns (bool) {
if (released) {
verifiedKYCAddresses[_to] = true;
}
return super.transferFrom(_from, _to, _value);
}
function approve(address _spender, uint256 _value) public isReleased returns (bool) {
return super.approve(_spender, _value);
}
function increaseApproval(address _spender, uint _addedValue) public isReleased returns (bool success) {
return super.increaseApproval(_spender, _addedValue);
}
function decreaseApproval(address _spender, uint _subtractedValue) public isReleased returns (bool success) {
return super.decreaseApproval(_spender, _subtractedValue);
}
function transferOwnership(address newOwner) public onlyOwner {
require(newOwner != owner);
require(lockedAddresses[newOwner] < now);
address oldOwner = owner;
super.transferOwnership(newOwner);
if (oldOwner != tokensWallet) {
allowed[tokensWallet][oldOwner] = 0;
emit Approval(tokensWallet, oldOwner, 0);
}
if (owner != tokensWallet) {
allowed[tokensWallet][owner] = balances[tokensWallet];
emit Approval(tokensWallet, owner, balances[tokensWallet]);
}
verifiedKYCAddresses[newOwner] = true;
emit KYCVerified(newOwner);
}
function changeTechAccountAddress(address _address) public onlyOwner {
require(_address != address(0) && _address != techAccount);
require(lockedAddresses[_address] < now);
techAccount = _address;
emit SetTechAccount(techAccount);
verifiedKYCAddresses[_address] = true;
emit KYCVerified(_address);
}
function mint(
address _to,
uint256 _amount
)
public
hasMintPermission
returns (bool)
{
totalSupply_ = totalSupply_.add(_amount);
require(totalSupply_ > 0);
require(totalSupply_ <= TOKENS_MAXIMUM_SUPPLY);
balances[_to] = balances[_to].add(_amount);
emit Mint(_to, _amount);
emit Transfer(address(0), _to, _amount);
return true;
}
function setMintingOracle(address _address) public hasMintPermission {
require(_address != address(0) && _address != mintingOracle);
mintingOracle = _address;
}
}