Completed Kyber Swap Proxy Contract.

This commit is contained in:
Sowmayjain 2019-03-23 03:55:46 +05:30
parent 8a099ff357
commit 19379111d7
3 changed files with 247 additions and 4 deletions

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@ -0,0 +1,238 @@
pragma solidity ^0.5.0;
library SafeMath {
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b, "Assertion Failed");
return c;
}
}
interface IERC20 {
function balanceOf(address who) external view returns (uint256);
function allowance(address _owner, address _spender) external view returns (uint256);
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);
}
interface KyberInterface {
function trade(
address src,
uint srcAmount,
address dest,
address destAddress,
uint maxDestAmount,
uint minConversionRate,
address walletId
) external payable returns (uint);
function getExpectedRate(
address src,
address dest,
uint srcQty
) external view returns (uint, uint);
}
contract Helper {
using SafeMath for uint;
using SafeMath for uint256;
address public eth; // 0xeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
address public kyber; // Kyber Proxy
address public admin; // InstaDApp Kyber Registered Admin
uint public maxCap = 2**255;
/**
* @dev fetching token from the trader if ERC20
* @param trader is the trader
* @param src is the token which is being sold
* @param srcAmt is the amount of token being sold
*/
function getToken(address trader, address src, uint srcAmt) internal returns (uint ethQty) {
if (src == eth) {
require(msg.value == srcAmt, "not-enough-src");
ethQty = srcAmt;
} else {
IERC20 tokenCall = IERC20(src);
tokenCall.transferFrom(trader, address(this), srcAmt);
}
}
/**
* @dev setting allowance to kyber for the "user proxy" if required
* @param token is the token address
*/
function setApproval(address token) internal returns (uint) {
IERC20 tokenCall = IERC20(token);
tokenCall.approve(kyber, maxCap);
}
/**
* @dev configuring token approval with user proxy
* @param token is the token
* @param spender is the user proxy
*/
function manageApproval(address token, address spender, uint srcAmt) internal view returns (uint) {
IERC20 tokenCall = IERC20(token);
uint tokenAllowance = tokenCall.allowance(address(this), kyber);
if (srcAmt > tokenAllowance) {
setApproval(token);
}
}
/**
* @dev getting rates from Kyber
* @param src is the token being sold
* @param dest is the token being bought
* @param srcAmt is the amount of token being sold
* @return expectedRate - the current rate
* @return slippageRate - rate with 3% slippage
*/
function getExpectedRate(
address src,
address dest,
uint srcAmt
) internal view returns (
uint expectedRate,
uint slippageRate
)
{
KyberInterface swapCall = KyberInterface(kyber);
(expectedRate, slippageRate) = swapCall.getExpectedRate(src, dest, srcAmt);
slippageRate = (slippageRate / 97) * 99; // changing slippage rate upto 99%
}
}
contract Swap is Helper {
/**
* @param what 0 for BUY & 1 for SELL
*/
event LogTrade(
uint what,
address src,
uint srcAmt,
address dest,
uint destAmt,
address beneficiary,
uint minConversionRate,
address affiliate
);
/**
* @dev buying token where destAmt is fixed
* @param src - token to sell
* @param dest - token to buy
* @param srcAmt - token amount to sell
* @param maxDestAmt is the max amount of token to be bought
*/
function buy(
address src,
address dest,
uint srcAmt,
uint maxDestAmt
) public payable returns (uint destAmt)
{
uint ethQty = getToken(msg.sender, src, srcAmt);
(, uint slippageRate) = getExpectedRate(src, dest, srcAmt);
KyberInterface swapCall = KyberInterface(kyber);
destAmt = swapCall.trade.value(ethQty)(
src,
srcAmt,
dest,
msg.sender,
maxDestAmt,
slippageRate,
admin
);
emit LogTrade(
0,
src,
srcAmt,
dest,
destAmt,
msg.sender,
slippageRate,
admin
);
}
/**
* @dev selling token where srcAmt is fixed
* @param src - token to sell
* @param srcAmt - token amount to sell
* @param dest - token to buy
*/
function sell(
address src,
address dest,
uint srcAmt
) public payable returns (uint destAmt)
{
uint ethQty = getToken(msg.sender, src, srcAmt);
(, uint slippageRate) = getExpectedRate(src, dest, srcAmt);
KyberInterface swapCall = KyberInterface(kyber);
destAmt = swapCall.trade.value(ethQty)(
src,
srcAmt,
dest,
msg.sender,
maxCap,
slippageRate,
admin
);
emit LogTrade(
1,
src,
srcAmt,
dest,
destAmt,
msg.sender,
slippageRate,
admin
);
// maxDestAmt usecase implementated on user proxy
if (src == eth && address(this).balance > 0) {
msg.sender.transfer(address(this).balance);
} else if (src != eth) {
IERC20 srcTkn = IERC20(src);
uint srcBal = srcTkn.balanceOf(address(this));
if (srcBal > 0) {
srcTkn.transfer(msg.sender, srcBal);
}
}
}
}
contract InstaTrade is Swap {
/**
* @dev setting up variables on deployment
*/
constructor(address _eth, address _kyber, address _admin) public {
eth = _eth; // 0xeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
kyber = _kyber; // 0x818E6FECD516Ecc3849DAf6845e3EC868087B755
admin = _admin;
}
}

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@ -1,7 +1,7 @@
pragma solidity 0.5.0;
import "./safemath.sol";
import "./Safemath.sol";
interface IERC20 {
function balanceOf(address who) external view returns (uint256);

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@ -294,7 +294,7 @@ contract UserNote {
*/
contract UserWallet is UserManager, UserNote {
event LogExecute(address target, uint srcNum, uint sessionNum);
event LogExecute(address sender, address target, uint srcNum, uint sessionNum);
/**
* @dev sets the "address registry", owner's last activity, owner's active period and initial owner
@ -326,10 +326,14 @@ contract UserWallet is UserManager, UserNote {
note
returns (bytes memory response)
{
require(_target != address(0), "user-proxy-target-address-required");
require(isExecutable(_target), "not-executable");
lastActivity = block.timestamp;
emit LogExecute(_target, srcNum, sessionNum);
emit LogExecute(
msg.sender,
_target,
srcNum,
sessionNum
);
// call contract in current context
assembly {
@ -355,6 +359,7 @@ contract UserWallet is UserManager, UserNote {
* and if manager then Throws if target is default proxy address
*/
function isExecutable(address proxyTarget) internal returns (bool) {
require(proxyTarget != address(0), "user-proxy-target-address-required");
(bool isLogic, bool isDefault) = isLogicAuthorised(proxyTarget);
require(isLogic, "logic-proxy-address-not-allowed");
if (isAuth(msg.sender)) {