Contract Source Code:
File 1 of 1 : BCNTToken
pragma solidity ^0.4.13;
library ECRecovery {
/**
* @dev Recover signer address from a message by using their signature
* @param hash bytes32 message, the hash is the signed message. What is recovered is the signer address.
* @param sig bytes signature, the signature is generated using web3.eth.sign()
*/
function recover(bytes32 hash, bytes sig)
internal
pure
returns (address)
{
bytes32 r;
bytes32 s;
uint8 v;
// Check the signature length
if (sig.length != 65) {
return (address(0));
}
// Divide the signature in r, s and v variables
// ecrecover takes the signature parameters, and the only way to get them
// currently is to use assembly.
// solium-disable-next-line security/no-inline-assembly
assembly {
r := mload(add(sig, 32))
s := mload(add(sig, 64))
v := byte(0, mload(add(sig, 96)))
}
// Version of signature should be 27 or 28, but 0 and 1 are also possible versions
if (v < 27) {
v += 27;
}
// If the version is correct return the signer address
if (v != 27 && v != 28) {
return (address(0));
} else {
// solium-disable-next-line arg-overflow
return ecrecover(hash, v, r, s);
}
}
/**
* toEthSignedMessageHash
* @dev prefix a bytes32 value with "\x19Ethereum Signed Message:"
* and hash the result
*/
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)
);
}
}
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);
}
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];
}
}
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
);
}
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;
}
}
contract StandardToken is ERC20, BasicToken {
using SafeMath for uint256;
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,
uint256 _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,
uint256 _subtractedValue
)
public
returns (bool)
{
uint256 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;
}
}
contract DepositFromPrivateToken is StandardToken {
using SafeMath for uint256;
PrivateToken public privateToken;
modifier onlyPrivateToken() {
require(msg.sender == address(privateToken));
_;
}
/**
* @dev Deposit is the function should only be called from PrivateToken
* When the user wants to deposit their private Token to Origin Token. They should
* let the Private Token invoke this function.
* @param _depositor address. The person who wants to deposit.
*/
function deposit(address _depositor, uint256 _value) public onlyPrivateToken returns(bool){
require(_value != 0);
balances[_depositor] = balances[_depositor].add(_value);
emit Transfer(privateToken, _depositor, _value);
return true;
}
}
contract BCNTToken is DepositFromPrivateToken{
using SafeMath for uint256;
string public constant name = "Bincentive Token"; // solium-disable-line uppercase
string public constant symbol = "BCNT"; // solium-disable-line uppercase
uint8 public constant decimals = 18; // solium-disable-line uppercase
uint256 public constant INITIAL_SUPPLY = 1000000000 * (10 ** uint256(decimals));
mapping(bytes => bool) internal signatures;
event TransferPreSigned(address indexed from, address indexed to, address indexed delegate, uint256 amount, uint256 fee);
/**
* @notice Submit a presigned transfer
* @param _signature bytes The signature, issued by the owner.
* @param _to address The address which you want to transfer to.
* @param _value uint256 The amount of tokens to be transferred.
* @param _fee uint256 The amount of tokens paid to msg.sender, by the owner.
* @param _nonce uint256 Presigned transaction number.
* @param _validUntil uint256 Block number until which the presigned transaction is still valid.
*/
function transferPreSigned(
bytes _signature,
address _to,
uint256 _value,
uint256 _fee,
uint256 _nonce,
uint256 _validUntil
)
public
returns (bool)
{
require(_to != address(0));
require(signatures[_signature] == false);
require(block.number <= _validUntil);
bytes32 hashedTx = ECRecovery.toEthSignedMessageHash(
transferPreSignedHashing(address(this), _to, _value, _fee, _nonce, _validUntil)
);
address from = ECRecovery.recover(hashedTx, _signature);
balances[from] = balances[from].sub(_value).sub(_fee);
balances[_to] = balances[_to].add(_value);
balances[msg.sender] = balances[msg.sender].add(_fee);
signatures[_signature] = true;
emit Transfer(from, _to, _value);
emit Transfer(from, msg.sender, _fee);
emit TransferPreSigned(from, _to, msg.sender, _value, _fee);
return true;
}
/**
* @notice Hash (keccak256) of the payload used by transferPreSigned
* @param _token address The address of the token.
* @param _to address The address which you want to transfer to.
* @param _value uint256 The amount of tokens to be transferred.
* @param _fee uint256 The amount of tokens paid to msg.sender, by the owner.
* @param _nonce uint256 Presigned transaction number.
* @param _validUntil uint256 Block number until which the presigned transaction is still valid.
*/
function transferPreSignedHashing(
address _token,
address _to,
uint256 _value,
uint256 _fee,
uint256 _nonce,
uint256 _validUntil
)
public
pure
returns (bytes32)
{
/* "0d2d1bf5": transferPreSigned(address,address,uint256,uint256,uint256,uint256) */
return keccak256(
abi.encodePacked(
bytes4(0x0d2d1bf5),
_token,
_to,
_value,
_fee,
_nonce,
_validUntil
)
);
}
/**
* @dev Constructor that gives _owner all of existing tokens.
*/
constructor(address _admin) public {
totalSupply_ = INITIAL_SUPPLY;
privateToken = new PrivateToken(
_admin, "Bincentive Private Token", "BCNP", decimals, INITIAL_SUPPLY
);
}
}
contract PrivateToken is StandardToken {
using SafeMath for uint256;
string public name; // solium-disable-line uppercase
string public symbol; // solium-disable-line uppercase
uint8 public decimals; // solium-disable-line uppercase
address public admin;
bool public isPublic;
uint256 public unLockTime;
DepositFromPrivateToken originToken;
event StartPublicSale(uint256 unlockTime);
event Deposit(address indexed from, uint256 value);
/**
* @dev check if msg.sender is allowed to deposit Origin token.
*/
function isDepositAllowed() internal view{
// If the tokens isn't public yet all transfering are limited to origin tokens
require(isPublic);
require(msg.sender == admin || block.timestamp > unLockTime);
}
/**
* @dev Deposit msg.sender's origin token to real token
*/
function deposit(address _depositor) public returns (bool){
isDepositAllowed();
uint256 _value;
_value = balances[_depositor];
require(_value > 0);
balances[_depositor] = 0;
require(originToken.deposit(_depositor, _value));
emit Deposit(_depositor, _value);
// This event is for those apps calculate balance from events rather than balanceOf
emit Transfer(_depositor, address(0), _value);
}
/**
* @dev Start Public sale and allow admin to deposit the token.
* normal users could deposit their tokens after the tokens unlocked
*/
function startPublicSale(uint256 _unLockTime) public onlyAdmin {
require(!isPublic);
isPublic = true;
unLockTime = _unLockTime;
emit StartPublicSale(_unLockTime);
}
/**
* @dev unLock the origin token and start the public sale.
*/
function unLock() public onlyAdmin{
require(isPublic);
unLockTime = block.timestamp;
}
modifier onlyAdmin() {
require(msg.sender == admin);
_;
}
constructor(address _admin, string _name, string _symbol, uint8 _decimals, uint256 _totalSupply) public{
originToken = DepositFromPrivateToken(msg.sender);
admin = _admin;
name = _name;
symbol = _symbol;
decimals = _decimals;
totalSupply_ = _totalSupply;
balances[admin] = _totalSupply;
emit Transfer(address(0), admin, _totalSupply);
}
}