Smart Contract Repository
InitializableAdminUpgradeabilityProxy

InitializableAdminUpgradeabilityProxy

Deploy on Alchemy

Contract Information

This contract is a proxy and the implementation details are not yet known.
More Info

InitializableAdminUpgradeabilityProxy Source Code

// SPDX-License-Identifier: agpl-3.0 pragma solidity 0.6.10; /** * @dev Interface of the ERC20 standard as defined in the EIP. */ 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. * * IMPORTANT: 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); }// SPDX-License-Identifier: agpl-3.0 pragma solidity 0.6.10; import {IERC20} from "./IERC20.sol"; interface IERC20Detailed is IERC20 { function name() external view returns(string memory); function symbol() external view returns(string memory); function decimals() external view returns(uint8); } // SPDX-License-Identifier: agpl-3.0 pragma solidity 0.6.10; interface ITransferHook { function onTransfer(address from, address to, uint256 amount) external; }pragma solidity ^0.6.2; /** * @dev Collection of functions related to the address type */ library Address { /** * @dev Returns true if `account` is a contract. * * [IMPORTANT] * ==== * It is unsafe to assume that an address for which this function returns * false is an externally-owned account (EOA) and not a contract. * * Among others, `isContract` will return false for the following * types of addresses: * * - an externally-owned account * - a contract in construction * - an address where a contract will be created * - an address where a contract lived, but was destroyed * ==== */ function isContract(address account) internal view returns (bool) { // According to EIP-1052, 0x0 is the value returned for not-yet created accounts // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned // for accounts without code, i.e. `keccak256('')` bytes32 codehash; bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470; // solhint-disable-next-line no-inline-assembly assembly { codehash := extcodehash(account) } return (codehash != accountHash && codehash != 0x0); } /** * @dev Replacement for Solidity's `transfer`: sends `amount` wei to * `recipient`, forwarding all available gas and reverting on errors. * * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost * of certain opcodes, possibly making contracts go over the 2300 gas limit * imposed by `transfer`, making them unable to receive funds via * `transfer`. {sendValue} removes this limitation. * * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more]. * * IMPORTANT: because control is transferred to `recipient`, care must be * taken to not create reentrancy vulnerabilities. Consider using * {ReentrancyGuard} or the * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern]. */ function sendValue(address payable recipient, uint256 amount) internal { require(address(this).balance >= amount, "Address: insufficient balance"); // solhint-disable-next-line avoid-low-level-calls, avoid-call-value (bool success, ) = recipient.call{ value: amount }(""); require(success, "Address: unable to send value, recipient may have reverted"); } }pragma solidity ^0.6.0; import './UpgradeabilityProxy.sol'; /** * @title BaseAdminUpgradeabilityProxy * @dev This contract combines an upgradeability proxy with an authorization * mechanism for administrative tasks. * All external functions in this contract must be guarded by the * `ifAdmin` modifier. See ethereum/solidity#3864 for a Solidity * feature proposal that would enable this to be done automatically. */ contract BaseAdminUpgradeabilityProxy is BaseUpgradeabilityProxy { /** * @dev Emitted when the administration has been transferred. * @param previousAdmin Address of the previous admin. * @param newAdmin Address of the new admin. */ event AdminChanged(address previousAdmin, address newAdmin); /** * @dev Storage slot with the admin of the contract. * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is * validated in the constructor. */ bytes32 internal constant ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103; /** * @dev Modifier to check whether the `msg.sender` is the admin. * If it is, it will run the function. Otherwise, it will delegate the call * to the implementation. */ modifier ifAdmin() { if (msg.sender == _admin()) { _; } else { _fallback(); } } /** * @return The address of the proxy admin. */ function admin() external ifAdmin returns (address) { return _admin(); } /** * @return The address of the implementation. */ function implementation() external ifAdmin returns (address) { return _implementation(); } /** * @dev Changes the admin of the proxy. * Only the current admin can call this function. * @param newAdmin Address to transfer proxy administration to. */ function changeAdmin(address newAdmin) external ifAdmin { require(newAdmin != address(0), "Cannot change the admin of a proxy to the zero address"); emit AdminChanged(_admin(), newAdmin); _setAdmin(newAdmin); } /** * @dev Upgrade the backing implementation of the proxy. * Only the admin can call this function. * @param newImplementation Address of the new implementation. */ function upgradeTo(address newImplementation) external ifAdmin { _upgradeTo(newImplementation); } /** * @dev Upgrade the backing implementation of the proxy and call a function * on the new implementation. * This is useful to initialize the proxied contract. * @param newImplementation Address of the new implementation. * @param data Data to send as msg.data in the low level call. * It should include the signature and the parameters of the function to be called, as described in * https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector-and-argument-encoding. */ function upgradeToAndCall(address newImplementation, bytes calldata data) payable external ifAdmin { _upgradeTo(newImplementation); (bool success,) = newImplementation.delegatecall(data); require(success); } /** * @return adm The admin slot. */ function _admin() internal view returns (address adm) { bytes32 slot = ADMIN_SLOT; assembly { adm := sload(slot) } } /** * @dev Sets the address of the proxy admin. * @param newAdmin Address of the new proxy admin. */ function _setAdmin(address newAdmin) internal { bytes32 slot = ADMIN_SLOT; assembly { sstore(slot, newAdmin) } } /** * @dev Only fall back when the sender is not the admin. */ function _willFallback() internal override virtual { require(msg.sender != _admin(), "Cannot call fallback function from the proxy admin"); super._willFallback(); } }pragma solidity ^0.6.0; import './BaseUpgradeabilityProxy.sol'; /** * @title UpgradeabilityProxy * @dev Extends BaseUpgradeabilityProxy with a constructor for initializing * implementation and init data. */ contract UpgradeabilityProxy is BaseUpgradeabilityProxy { /** * @dev Contract constructor. * @param _logic Address of the initial implementation. * @param _data Data to send as msg.data to the implementation to initialize the proxied contract. * It should include the signature and the parameters of the function to be called, as described in * https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector-and-argument-encoding. * This parameter is optional, if no data is given the initialization call to proxied contract will be skipped. */ constructor(address _logic, bytes memory _data) public payable { assert(IMPLEMENTATION_SLOT == bytes32(uint256(keccak256('eip1967.proxy.implementation')) - 1)); _setImplementation(_logic); if(_data.length > 0) { (bool success,) = _logic.delegatecall(_data); require(success); } } }pragma solidity ^0.6.0; import './Proxy.sol'; import './Address.sol'; /** * @title BaseUpgradeabilityProxy * @dev This contract implements a proxy that allows to change the * implementation address to which it will delegate. * Such a change is called an implementation upgrade. */ contract BaseUpgradeabilityProxy is Proxy { /** * @dev Emitted when the implementation is upgraded. * @param implementation Address of the new implementation. */ event Upgraded(address indexed implementation); /** * @dev Storage slot with the address of the current implementation. * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is * validated in the constructor. */ bytes32 internal constant IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc; /** * @dev Returns the current implementation. * @return impl Address of the current implementation */ function _implementation() internal override view returns (address impl) { bytes32 slot = IMPLEMENTATION_SLOT; assembly { impl := sload(slot) } } /** * @dev Upgrades the proxy to a new implementation. * @param newImplementation Address of the new implementation. */ function _upgradeTo(address newImplementation) internal { _setImplementation(newImplementation); emit Upgraded(newImplementation); } /** * @dev Sets the implementation address of the proxy. * @param newImplementation Address of the new implementation. */ function _setImplementation(address newImplementation) internal { require(Address.isContract(newImplementation), "Cannot set a proxy implementation to a non-contract address"); bytes32 slot = IMPLEMENTATION_SLOT; assembly { sstore(slot, newImplementation) } } }pragma solidity ^0.6.0; /** * @title Proxy * @dev Implements delegation of calls to other contracts, with proper * forwarding of return values and bubbling of failures. * It defines a fallback function that delegates all calls to the address * returned by the abstract _implementation() internal function. */ abstract contract Proxy { /** * @dev Fallback function. * Implemented entirely in `_fallback`. */ fallback () payable external { _fallback(); } /** * @return The Address of the implementation. */ function _implementation() internal virtual view returns (address); /** * @dev Delegates execution to an implementation contract. * This is a low level function that doesn't return to its internal call site. * It will return to the external caller whatever the implementation returns. * @param implementation Address to delegate. */ function _delegate(address implementation) internal { assembly { // Copy msg.data. We take full control of memory in this inline assembly // block because it will not return to Solidity code. We overwrite the // Solidity scratch pad at memory position 0. calldatacopy(0, 0, calldatasize()) // Call the implementation. // out and outsize are 0 because we don't know the size yet. let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0) // Copy the returned data. returndatacopy(0, 0, returndatasize()) switch result // delegatecall returns 0 on error. case 0 { revert(0, returndatasize()) } default { return(0, returndatasize()) } } } /** * @dev Function that is run as the first thing in the fallback function. * Can be redefined in derived contracts to add functionality. * Redefinitions must call super._willFallback(). */ function _willFallback() internal virtual { } /** * @dev fallback implementation. * Extracted to enable manual triggering. */ function _fallback() internal { _willFallback(); _delegate(_implementation()); } }// SPDX-License-Identifier: MIT pragma solidity ^0.6.0; /* * @dev Provides information about the current execution context, including the * sender of the transaction and its data. While these are generally available * via msg.sender and msg.data, they should not be accessed in such a direct * manner, since when dealing with GSN meta-transactions the account sending and * paying for execution may not be the actual sender (as far as an application * is concerned). * * This contract is only required for intermediate, library-like contracts. */ abstract contract Context { function _msgSender() internal view virtual returns (address payable) { return msg.sender; } function _msgData() internal view virtual returns (bytes memory) { this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691 return msg.data; } }// SPDX-License-Identifier: MIT pragma solidity ^0.6.0; import "./Context.sol"; import "../interfaces/IERC20.sol"; import "./SafeMath.sol"; import "./Address.sol"; /** * @dev Implementation of the {IERC20} interface. * * 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 {ERC20PresetMinterPauser}. * * TIP: For a detailed writeup see our guide * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How * to implement supply mechanisms]. * * 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 Context, IERC20 { using SafeMath for uint256; using Address for address; mapping (address => uint256) private _balances; mapping (address => mapping (address => uint256)) private _allowances; uint256 private _totalSupply; string internal _name; string internal _symbol; uint8 private _decimals; /** * @dev Sets the values for {name} and {symbol}, initializes {decimals} with * a default value of 18. * * To select a different value for {decimals}, use {_setupDecimals}. * * All three of these values are immutable: they can only be set once during * construction. */ constructor (string memory name, string memory symbol) public { _name = name; _symbol = symbol; _decimals = 18; } /** * @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. This is the value {ERC20} uses, unless {_setupDecimals} is * called. * * NOTE: 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; } /** * @dev See {IERC20-totalSupply}. */ function totalSupply() public view override returns (uint256) { return _totalSupply; } /** * @dev See {IERC20-balanceOf}. */ function balanceOf(address account) public view override 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 virtual override returns (bool) { _transfer(_msgSender(), recipient, amount); return true; } /** * @dev See {IERC20-allowance}. */ function allowance(address owner, address spender) public view virtual override returns (uint256) { return _allowances[owner][spender]; } /** * @dev See {IERC20-approve}. * * Requirements: * * - `spender` cannot be the zero address. */ function approve(address spender, uint256 amount) public virtual override returns (bool) { _approve(_msgSender(), spender, amount); 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 `amount`. * - the caller must have allowance for ``sender``'s tokens of at least * `amount`. */ function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) { _transfer(sender, recipient, amount); _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance")); 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 virtual returns (bool) { _approve(_msgSender(), spender, _allowances[_msgSender()][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 virtual returns (bool) { _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero")); 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 virtual { require(sender != address(0), "ERC20: transfer from the zero address"); require(recipient != address(0), "ERC20: transfer to the zero address"); _beforeTokenTransfer(sender, recipient, amount); _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance"); _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 virtual { require(account != address(0), "ERC20: mint to the zero address"); _beforeTokenTransfer(address(0), account, amount); _totalSupply = _totalSupply.add(amount); _balances[account] = _balances[account].add(amount); emit Transfer(address(0), account, amount); } /** * @dev Destroys `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 amount) internal virtual { require(account != address(0), "ERC20: burn from the zero address"); _beforeTokenTransfer(account, address(0), amount); _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance"); _totalSupply = _totalSupply.sub(amount); emit Transfer(account, address(0), amount); } /** * @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 amount) internal virtual { require(owner != address(0), "ERC20: approve from the zero address"); require(spender != address(0), "ERC20: approve to the zero address"); _allowances[owner][spender] = amount; emit Approval(owner, spender, amount); } /** * @dev Sets {decimals} to a value other than the default one of 18. * * WARNING: This function should only be called from the constructor. Most * applications that interact with token contracts will not expect * {decimals} to ever change, and may work incorrectly if it does. */ function _setupDecimals(uint8 decimals_) internal { _decimals = decimals_; } /** * @dev Hook that is called before any transfer of tokens. This includes * minting and burning. * * Calling conditions: * * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens * will be to transferred to `to`. * - when `from` is zero, `amount` tokens will be minted for `to`. * - when `to` is zero, `amount` of ``from``'s tokens will be burned. * - `from` and `to` are never both zero. * * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks]. */ function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { } }pragma solidity ^0.6.0; /** * @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) { return sub(a, b, "SafeMath: subtraction overflow"); } /** * @dev Returns the subtraction of two unsigned integers, reverting with custom message on * overflow (when the result is negative). * * Counterpart to Solidity's `-` operator. * * Requirements: * - Subtraction cannot overflow. */ function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) { require(b <= a, errorMessage); 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-contracts/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) { return div(a, b, "SafeMath: division by zero"); } /** * @dev Returns the integer division of two unsigned integers. Reverts with custom message 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, string memory errorMessage) internal pure returns (uint256) { // Solidity only automatically asserts when dividing by 0 require(b > 0, errorMessage); 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) { return mod(a, b, "SafeMath: modulo by zero"); } /** * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo), * Reverts with custom message 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, string memory errorMessage) internal pure returns (uint256) { require(b != 0, errorMessage); return a % b; } }// SPDX-License-Identifier: agpl-3.0 pragma solidity ^0.6.10; import "./BaseAdminUpgradeabilityProxy.sol"; import "./InitializableUpgradeabilityProxy.sol"; /** * @title InitializableAdminUpgradeabilityProxy * @dev Extends from BaseAdminUpgradeabilityProxy with an initializer for * initializing the implementation, admin, and init data. */ contract InitializableAdminUpgradeabilityProxy is BaseAdminUpgradeabilityProxy, InitializableUpgradeabilityProxy { /** * Contract initializer. * @param _logic address of the initial implementation. * @param _admin Address of the proxy administrator. * @param _data Data to send as msg.data to the implementation to initialize the proxied contract. * It should include the signature and the parameters of the function to be called, as described in * https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector-and-argument-encoding. * This parameter is optional, if no data is given the initialization call to proxied contract will be skipped. */ function initialize(address _logic, address _admin, bytes memory _data) public payable { require(_implementation() == address(0)); InitializableUpgradeabilityProxy.initialize(_logic, _data); assert(ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1)); _setAdmin(_admin); } /** * @dev Only fall back when the sender is not the admin. */ function _willFallback() internal override(BaseAdminUpgradeabilityProxy, Proxy) { BaseAdminUpgradeabilityProxy._willFallback(); } } // SPDX-License-Identifier: agpl-3.0 pragma solidity ^0.6.10; import "./BaseUpgradeabilityProxy.sol"; /** * @title InitializableUpgradeabilityProxy * @dev Extends BaseUpgradeabilityProxy with an initializer for initializing * implementation and init data. */ contract InitializableUpgradeabilityProxy is BaseUpgradeabilityProxy { /** * @dev Contract initializer. * @param _logic Address of the initial implementation. * @param _data Data to send as msg.data to the implementation to initialize the proxied contract. * It should include the signature and the parameters of the function to be called, as described in * https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector-and-argument-encoding. * This parameter is optional, if no data is given the initialization call to proxied contract will be skipped. */ function initialize(address _logic, bytes memory _data) public payable { require(_implementation() == address(0)); assert(IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1)); _setImplementation(_logic); if (_data.length > 0) { (bool success, ) = _logic.delegatecall(_data); require(success); } } } // SPDX-License-Identifier: agpl-3.0 pragma solidity 0.6.10; import {ERC20} from "../open-zeppelin/ERC20.sol"; import {ITransferHook} from "../interfaces/ITransferHook.sol"; import {VersionedInitializable} from "../utils/VersionedInitializable.sol"; /** * @notice implementation of the AAVE token contract * @author Aave */ contract AaveToken is ERC20, VersionedInitializable { /// @dev snapshot of a value on a specific block, used for balances struct Snapshot { uint128 blockNumber; uint128 value; } string internal constant NAME = "Aave Token"; string internal constant SYMBOL = "AAVE"; uint8 internal constant DECIMALS = 18; /// @dev the amount being distributed for the LEND -> AAVE migration uint256 internal constant MIGRATION_AMOUNT = 13000000 ether; /// @dev the amount being distributed for the PSI and PEI uint256 internal constant DISTRIBUTION_AMOUNT = 3000000 ether; uint256 public constant REVISION = 1; /// @dev owner => next valid nonce to submit with permit() mapping (address => uint256) public _nonces; mapping (address => mapping (uint256 => Snapshot)) public _snapshots; mapping (address => uint256) public _countsSnapshots; /// @dev reference to the Aave governance contract to call (if initialized) on _beforeTokenTransfer /// !!! IMPORTANT The Aave governance is considered a trustable contract, being its responsibility /// to control all potential reentrancies by calling back the AaveToken ITransferHook public _aaveGovernance; bytes32 public DOMAIN_SEPARATOR; bytes public constant EIP712_REVISION = bytes("1"); bytes32 internal constant EIP712_DOMAIN = keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"); bytes32 public constant PERMIT_TYPEHASH = keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"); event SnapshotDone(address owner, uint128 oldValue, uint128 newValue); constructor() ERC20(NAME, SYMBOL) public {} /** * @dev initializes the contract upon assignment to the InitializableAdminUpgradeabilityProxy * @param migrator the address of the LEND -> AAVE migration contract * @param distributor the address of the AAVE distribution contract */ function initialize( address migrator, address distributor, ITransferHook aaveGovernance ) external initializer { uint256 chainId; //solium-disable-next-line assembly { chainId := chainid() } DOMAIN_SEPARATOR = keccak256(abi.encode( EIP712_DOMAIN, keccak256(bytes(NAME)), keccak256(EIP712_REVISION), chainId, address(this) )); _name = NAME; _symbol = SYMBOL; _setupDecimals(DECIMALS); _aaveGovernance = aaveGovernance; _mint(migrator, MIGRATION_AMOUNT); _mint(distributor, DISTRIBUTION_AMOUNT); } /** * @dev implements the permit function as for https://github.com/ethereum/EIPs/blob/8a34d644aacf0f9f8f00815307fd7dd5da07655f/EIPS/eip-2612.md * @param owner the owner of the funds * @param spender the spender * @param value the amount * @param deadline the deadline timestamp, type(uint256).max for no deadline * @param v signature param * @param s signature param * @param r signature param */ function permit( address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s ) external { require(owner != address(0), "INVALID_OWNER"); //solium-disable-next-line require(block.timestamp <= deadline, "INVALID_EXPIRATION"); uint256 currentValidNonce = _nonces[owner]; bytes32 digest = keccak256( abi.encodePacked( "\x19\x01", DOMAIN_SEPARATOR, keccak256( abi.encode(PERMIT_TYPEHASH, owner, spender, value, currentValidNonce, deadline)) ) ); require(owner == ecrecover(digest, v, r, s), "INVALID_SIGNATURE"); _nonces[owner] = currentValidNonce.add(1); _approve(owner, spender, value); } /** * @dev returns the revision of the implementation contract */ function getRevision() internal pure override returns (uint256) { return REVISION; } /** * @dev Writes a snapshot for an owner of tokens * @param owner The owner of the tokens * @param oldValue The value before the operation that is gonna be executed after the snapshot * @param newValue The value after the operation */ function _writeSnapshot(address owner, uint128 oldValue, uint128 newValue) internal { uint128 currentBlock = uint128(block.number); uint256 ownerCountOfSnapshots = _countsSnapshots[owner]; mapping (uint256 => Snapshot) storage snapshotsOwner = _snapshots[owner]; // Doing multiple operations in the same block if (ownerCountOfSnapshots != 0 && snapshotsOwner[ownerCountOfSnapshots.sub(1)].blockNumber == currentBlock) { snapshotsOwner[ownerCountOfSnapshots.sub(1)].value = newValue; } else { snapshotsOwner[ownerCountOfSnapshots] = Snapshot(currentBlock, newValue); _countsSnapshots[owner] = ownerCountOfSnapshots.add(1); } emit SnapshotDone(owner, oldValue, newValue); } /** * @dev Writes a snapshot before any operation involving transfer of value: _transfer, _mint and _burn * - On _transfer, it writes snapshots for both "from" and "to" * - On _mint, only for _to * - On _burn, only for _from * @param from the from address * @param to the to address * @param amount the amount to transfer */ function _beforeTokenTransfer(address from, address to, uint256 amount) internal override { if (from == to) { return; } if (from != address(0)) { uint256 fromBalance = balanceOf(from); _writeSnapshot(from, uint128(fromBalance), uint128(fromBalance.sub(amount))); } if (to != address(0)) { uint256 toBalance = balanceOf(to); _writeSnapshot(to, uint128(toBalance), uint128(toBalance.add(amount))); } // caching the aave governance address to avoid multiple state loads ITransferHook aaveGovernance = _aaveGovernance; if (aaveGovernance != ITransferHook(0)) { aaveGovernance.onTransfer(from, to, amount); } } }// SPDX-License-Identifier: agpl-3.0 pragma solidity 0.6.10; /** * @title VersionedInitializable * * @dev Helper contract to support initializer functions. To use it, replace * the constructor with a function that has the `initializer` modifier. * WARNING: Unlike constructors, initializer functions must be manually * invoked. This applies both to deploying an Initializable contract, as well * as extending an Initializable contract via inheritance. * WARNING: When used with inheritance, manual care must be taken to not invoke * a parent initializer twice, or ensure that all initializers are idempotent, * because this is not dealt with automatically as with constructors. * * @author Aave, inspired by the OpenZeppelin Initializable contract */ abstract contract VersionedInitializable { /** * @dev Indicates that the contract has been initialized. */ uint256 internal lastInitializedRevision = 0; /** * @dev Modifier to use in the initializer function of a contract. */ modifier initializer() { uint256 revision = getRevision(); require(revision > lastInitializedRevision, "Contract instance has already been initialized"); lastInitializedRevision = revision; _; } /// @dev returns the revision number of the contract. /// Needs to be defined in the inherited class as a constant. function getRevision() internal pure virtual returns(uint256); // Reserved storage space to allow for layout changes in the future. uint256[50] private ______gap; } // SPDX-License-Identifier: agpl-3.0 pragma solidity 0.6.10; import {IERC20} from "../interfaces/IERC20.sol"; import {SafeMath} from "../open-zeppelin/SafeMath.sol"; import {VersionedInitializable} from "../utils/VersionedInitializable.sol"; /** * @title LendToAaveMigrator * @notice This contract implements the migration from LEND to AAVE token * @author Aave */ contract LendToAaveMigrator is VersionedInitializable { using SafeMath for uint256; IERC20 public immutable AAVE; IERC20 public immutable LEND; uint256 public immutable LEND_AAVE_RATIO; uint256 public constant REVISION = 1; uint256 public _totalLendMigrated; /** * @dev emitted on migration * @param sender the caller of the migration * @param amount the amount being migrated */ event LendMigrated(address indexed sender, uint256 indexed amount); /** * @param aave the address of the AAVE token * @param lend the address of the LEND token * @param lendAaveRatio the exchange rate between LEND and AAVE */ constructor(IERC20 aave, IERC20 lend, uint256 lendAaveRatio) public { AAVE = aave; LEND = lend; LEND_AAVE_RATIO = lendAaveRatio; } /** * @dev initializes the implementation */ function initialize() public initializer { } /** * @dev returns true if the migration started */ function migrationStarted() external view returns(bool) { return lastInitializedRevision != 0; } /** * @dev executes the migration from LEND to AAVE. Users need to give allowance to this contract to transfer LEND before executing * this transaction. * @param amount the amount of LEND to be migrated */ function migrateFromLEND(uint256 amount) external { require(lastInitializedRevision != 0, "MIGRATION_NOT_STARTED"); _totalLendMigrated = _totalLendMigrated.add(amount); LEND.transferFrom(msg.sender, address(this), amount); AAVE.transfer(msg.sender, amount.div(LEND_AAVE_RATIO)); emit LendMigrated(msg.sender, amount); } /** * @dev returns the implementation revision * @return the implementation revision */ function getRevision() internal pure override returns (uint256) { return REVISION; } }// SPDX-License-Identifier: agpl-3.0 pragma solidity 0.6.10; import "../interfaces/IERC20.sol"; contract DoubleTransferHelper { IERC20 public immutable AAVE; constructor(IERC20 aave) public { AAVE = aave; } function doubleSend(address to, uint256 amount1, uint256 amount2) external { AAVE.transfer(to, amount1); AAVE.transfer(to, amount2); } }// SPDX-License-Identifier: agpl-3.0 pragma solidity 0.6.10; import "../open-zeppelin/ERC20.sol"; /** * @title ERC20Mintable * @dev ERC20 minting logic */ contract MintableErc20 is ERC20 { constructor(string memory name, string memory symbol, uint8 decimals) ERC20(name, symbol) public { _setupDecimals(decimals); } /** * @dev Function to mint tokens * @param value The amount of tokens to mint. * @return A boolean that indicates if the operation was successful. */ function mint(uint256 value) public returns (bool) { _mint(msg.sender, value); return true; } } // SPDX-License-Identifier: agpl-3.0 pragma solidity 0.6.10; import {ITransferHook} from "../interfaces/ITransferHook.sol"; contract MockTransferHook is ITransferHook { event MockHookEvent(); function onTransfer(address from, address to, uint256 amount) external override { emit MockHookEvent(); } }
< // SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.10;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
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.
     *
     * IMPORTANT: 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);
}// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.10;

import {IERC20} from "./IERC20.sol";

interface IERC20Detailed is IERC20 {
    function name() external view returns(string memory);
    function symbol() external view returns(string memory);
    function decimals() external view returns(uint8);
}
// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.10;

interface ITransferHook {
    function onTransfer(address from, address to, uint256 amount) external;
}pragma solidity ^0.6.2;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // According to EIP-1052, 0x0 is the value returned for not-yet created accounts
        // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
        // for accounts without code, i.e. `keccak256('')`
        bytes32 codehash;
        bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
        // solhint-disable-next-line no-inline-assembly
        assembly { codehash := extcodehash(account) }
        return (codehash != accountHash && codehash != 0x0);
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }
}pragma solidity ^0.6.0;

import './UpgradeabilityProxy.sol';

/**
 * @title BaseAdminUpgradeabilityProxy
 * @dev This contract combines an upgradeability proxy with an authorization
 * mechanism for administrative tasks.
 * All external functions in this contract must be guarded by the
 * `ifAdmin` modifier. See ethereum/solidity#3864 for a Solidity
 * feature proposal that would enable this to be done automatically.
 */
contract BaseAdminUpgradeabilityProxy is BaseUpgradeabilityProxy {
  /**
   * @dev Emitted when the administration has been transferred.
   * @param previousAdmin Address of the previous admin.
   * @param newAdmin Address of the new admin.
   */
  event AdminChanged(address previousAdmin, address newAdmin);

  /**
   * @dev Storage slot with the admin of the contract.
   * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
   * validated in the constructor.
   */

  bytes32 internal constant ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;

  /**
   * @dev Modifier to check whether the `msg.sender` is the admin.
   * If it is, it will run the function. Otherwise, it will delegate the call
   * to the implementation.
   */
  modifier ifAdmin() {
    if (msg.sender == _admin()) {
      _;
    } else {
      _fallback();
    }
  }

  /**
   * @return The address of the proxy admin.
   */
  function admin() external ifAdmin returns (address) {
    return _admin();
  }

  /**
   * @return The address of the implementation.
   */
  function implementation() external ifAdmin returns (address) {
    return _implementation();
  }

  /**
   * @dev Changes the admin of the proxy.
   * Only the current admin can call this function.
   * @param newAdmin Address to transfer proxy administration to.
   */
  function changeAdmin(address newAdmin) external ifAdmin {
    require(newAdmin != address(0), "Cannot change the admin of a proxy to the zero address");
    emit AdminChanged(_admin(), newAdmin);
    _setAdmin(newAdmin);
  }

  /**
   * @dev Upgrade the backing implementation of the proxy.
   * Only the admin can call this function.
   * @param newImplementation Address of the new implementation.
   */
  function upgradeTo(address newImplementation) external ifAdmin {
    _upgradeTo(newImplementation);
  }

  /**
   * @dev Upgrade the backing implementation of the proxy and call a function
   * on the new implementation.
   * This is useful to initialize the proxied contract.
   * @param newImplementation Address of the new implementation.
   * @param data Data to send as msg.data in the low level call.
   * It should include the signature and the parameters of the function to be called, as described in
   * https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector-and-argument-encoding.
   */
  function upgradeToAndCall(address newImplementation, bytes calldata data) payable external ifAdmin {
    _upgradeTo(newImplementation);
    (bool success,) = newImplementation.delegatecall(data);
    require(success);
  }

  /**
   * @return adm The admin slot.
   */
  function _admin() internal view returns (address adm) {
    bytes32 slot = ADMIN_SLOT;
    assembly {
      adm := sload(slot)
    }
  }

  /**
   * @dev Sets the address of the proxy admin.
   * @param newAdmin Address of the new proxy admin.
   */
  function _setAdmin(address newAdmin) internal {
    bytes32 slot = ADMIN_SLOT;

    assembly {
      sstore(slot, newAdmin)
    }
  }

  /**
   * @dev Only fall back when the sender is not the admin.
   */
  function _willFallback() internal override virtual {
    require(msg.sender != _admin(), "Cannot call fallback function from the proxy admin");
    super._willFallback();
  }
}pragma solidity ^0.6.0;

import './BaseUpgradeabilityProxy.sol';

/**
 * @title UpgradeabilityProxy
 * @dev Extends BaseUpgradeabilityProxy with a constructor for initializing
 * implementation and init data.
 */
contract UpgradeabilityProxy is BaseUpgradeabilityProxy {
  /**
   * @dev Contract constructor.
   * @param _logic Address of the initial implementation.
   * @param _data Data to send as msg.data to the implementation to initialize the proxied contract.
   * It should include the signature and the parameters of the function to be called, as described in
   * https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector-and-argument-encoding.
   * This parameter is optional, if no data is given the initialization call to proxied contract will be skipped.
   */
  constructor(address _logic, bytes memory _data) public payable {
    assert(IMPLEMENTATION_SLOT == bytes32(uint256(keccak256('eip1967.proxy.implementation')) - 1));
    _setImplementation(_logic);
    if(_data.length > 0) {
      (bool success,) = _logic.delegatecall(_data);
      require(success);
    }
  }  
}pragma solidity ^0.6.0;

import './Proxy.sol';
import './Address.sol';

/**
 * @title BaseUpgradeabilityProxy
 * @dev This contract implements a proxy that allows to change the
 * implementation address to which it will delegate.
 * Such a change is called an implementation upgrade.
 */
contract BaseUpgradeabilityProxy is Proxy {
  /**
   * @dev Emitted when the implementation is upgraded.
   * @param implementation Address of the new implementation.
   */
  event Upgraded(address indexed implementation);

  /**
   * @dev Storage slot with the address of the current implementation.
   * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
   * validated in the constructor.
   */
  bytes32 internal constant IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;

  /**
   * @dev Returns the current implementation.
   * @return impl Address of the current implementation
   */
  function _implementation() internal override view returns (address impl) {
    bytes32 slot = IMPLEMENTATION_SLOT;
    assembly {
      impl := sload(slot)
    }
  }

  /**
   * @dev Upgrades the proxy to a new implementation.
   * @param newImplementation Address of the new implementation.
   */
  function _upgradeTo(address newImplementation) internal {
    _setImplementation(newImplementation);
    emit Upgraded(newImplementation);
  }

  /**
   * @dev Sets the implementation address of the proxy.
   * @param newImplementation Address of the new implementation.
   */
  function _setImplementation(address newImplementation) internal {
    require(Address.isContract(newImplementation), "Cannot set a proxy implementation to a non-contract address");

    bytes32 slot = IMPLEMENTATION_SLOT;

    assembly {
      sstore(slot, newImplementation)
    }
  }
}pragma solidity ^0.6.0;

/**
 * @title Proxy
 * @dev Implements delegation of calls to other contracts, with proper
 * forwarding of return values and bubbling of failures.
 * It defines a fallback function that delegates all calls to the address
 * returned by the abstract _implementation() internal function.
 */
abstract contract Proxy {
  /**
   * @dev Fallback function.
   * Implemented entirely in `_fallback`.
   */
  fallback () payable external {
    _fallback();
  }

  /**
   * @return The Address of the implementation.
   */
  function _implementation() internal virtual view returns (address);

  /**
   * @dev Delegates execution to an implementation contract.
   * This is a low level function that doesn't return to its internal call site.
   * It will return to the external caller whatever the implementation returns.
   * @param implementation Address to delegate.
   */
  function _delegate(address implementation) internal {
    assembly {
      // Copy msg.data. We take full control of memory in this inline assembly
      // block because it will not return to Solidity code. We overwrite the
      // Solidity scratch pad at memory position 0.
      calldatacopy(0, 0, calldatasize())

      // Call the implementation.
      // out and outsize are 0 because we don't know the size yet.
      let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)

      // Copy the returned data.
      returndatacopy(0, 0, returndatasize())

      switch result
      // delegatecall returns 0 on error.
      case 0 { revert(0, returndatasize()) }
      default { return(0, returndatasize()) }
    }
  }

  /**
   * @dev Function that is run as the first thing in the fallback function.
   * Can be redefined in derived contracts to add functionality.
   * Redefinitions must call super._willFallback().
   */
  function _willFallback() internal virtual {
  }

  /**
   * @dev fallback implementation.
   * Extracted to enable manual triggering.
   */
  function _fallback() internal {
    _willFallback();
    _delegate(_implementation());
  }
}// SPDX-License-Identifier: MIT

pragma solidity ^0.6.0;

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}// SPDX-License-Identifier: MIT

pragma solidity ^0.6.0;

import "./Context.sol";
import "../interfaces/IERC20.sol";
import "./SafeMath.sol";
import "./Address.sol";

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * 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 {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * 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 Context, IERC20 {
    using SafeMath for uint256;
    using Address for address;

    mapping (address => uint256) private _balances;

    mapping (address => mapping (address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string internal _name;
    string internal _symbol;
    uint8 private _decimals;

    /**
     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
     * a default value of 18.
     *
     * To select a different value for {decimals}, use {_setupDecimals}.
     *
     * All three of these values are immutable: they can only be set once during
     * construction.
     */
    constructor (string memory name, string memory symbol) public {
        _name = name;
        _symbol = symbol;
        _decimals = 18;
    }

    /**
     * @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. This is the value {ERC20} uses, unless {_setupDecimals} is
     * called.
     *
     * NOTE: 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;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view override 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 virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        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 `amount`.
     * - the caller must have allowance for ``sender``'s tokens of at least
     * `amount`.
     */
    function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        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 virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][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 virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        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 virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(sender, recipient, amount);

        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _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 virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `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 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }

    /**
     * @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 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Sets {decimals} to a value other than the default one of 18.
     *
     * WARNING: This function should only be called from the constructor. Most
     * applications that interact with token contracts will not expect
     * {decimals} to ever change, and may work incorrectly if it does.
     */
    function _setupDecimals(uint8 decimals_) internal {
        _decimals = decimals_;
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be to transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
}pragma solidity ^0.6.0;

/**
 * @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) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        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-contracts/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) {
        return div(a, b, "SafeMath: division by zero");
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts with custom message 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, string memory errorMessage) internal pure returns (uint256) {
        // Solidity only automatically asserts when dividing by 0
        require(b > 0, errorMessage);
        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) {
        return mod(a, b, "SafeMath: modulo by zero");
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message 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, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}// SPDX-License-Identifier: agpl-3.0
pragma solidity ^0.6.10;

import "./BaseAdminUpgradeabilityProxy.sol";
import "./InitializableUpgradeabilityProxy.sol";

/**
 * @title InitializableAdminUpgradeabilityProxy
 * @dev Extends from BaseAdminUpgradeabilityProxy with an initializer for 
 * initializing the implementation, admin, and init data.
 */
contract InitializableAdminUpgradeabilityProxy is BaseAdminUpgradeabilityProxy, InitializableUpgradeabilityProxy {
    /**
   * Contract initializer.
   * @param _logic address of the initial implementation.
   * @param _admin Address of the proxy administrator.
   * @param _data Data to send as msg.data to the implementation to initialize the proxied contract.
   * It should include the signature and the parameters of the function to be called, as described in
   * https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector-and-argument-encoding.
   * This parameter is optional, if no data is given the initialization call to proxied contract will be skipped.
   */
    function initialize(address _logic, address _admin, bytes memory _data) public payable {
        require(_implementation() == address(0));
        InitializableUpgradeabilityProxy.initialize(_logic, _data);
        assert(ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
        _setAdmin(_admin);
    }

    /**
    * @dev Only fall back when the sender is not the admin.
    */
    function _willFallback() internal override(BaseAdminUpgradeabilityProxy, Proxy) {
        BaseAdminUpgradeabilityProxy._willFallback();
    }

}
// SPDX-License-Identifier: agpl-3.0
pragma solidity ^0.6.10;

import "./BaseUpgradeabilityProxy.sol";

/**
 * @title InitializableUpgradeabilityProxy
 * @dev Extends BaseUpgradeabilityProxy with an initializer for initializing
 * implementation and init data.
 */
contract InitializableUpgradeabilityProxy is BaseUpgradeabilityProxy {
    /**
   * @dev Contract initializer.
   * @param _logic Address of the initial implementation.
   * @param _data Data to send as msg.data to the implementation to initialize the proxied contract.
   * It should include the signature and the parameters of the function to be called, as described in
   * https://solidity.readthedocs.io/en/v0.4.24/abi-spec.html#function-selector-and-argument-encoding.
   * This parameter is optional, if no data is given the initialization call to proxied contract will be skipped.
   */
    function initialize(address _logic, bytes memory _data) public payable {
        require(_implementation() == address(0));
        assert(IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
        _setImplementation(_logic);
        if (_data.length > 0) {
            (bool success, ) = _logic.delegatecall(_data);
            require(success);
        }
    }
}
// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.10;

import {ERC20} from "../open-zeppelin/ERC20.sol";
import {ITransferHook} from "../interfaces/ITransferHook.sol";
import {VersionedInitializable} from "../utils/VersionedInitializable.sol";


/**
* @notice implementation of the AAVE token contract
* @author Aave
*/
contract AaveToken is ERC20, VersionedInitializable {

    /// @dev snapshot of a value on a specific block, used for balances
    struct Snapshot {
        uint128 blockNumber;
        uint128 value;
    }

    string internal constant NAME = "Aave Token";
    string internal constant SYMBOL = "AAVE";
    uint8 internal constant DECIMALS = 18;

    /// @dev the amount being distributed for the LEND -> AAVE migration
    uint256 internal constant MIGRATION_AMOUNT = 13000000 ether;

    /// @dev the amount being distributed for the PSI and PEI
    uint256 internal constant DISTRIBUTION_AMOUNT = 3000000 ether;

    uint256 public constant REVISION = 1;

    /// @dev owner => next valid nonce to submit with permit()
    mapping (address => uint256) public _nonces;

    mapping (address => mapping (uint256 => Snapshot)) public _snapshots;

    mapping (address => uint256) public _countsSnapshots;

    /// @dev reference to the Aave governance contract to call (if initialized) on _beforeTokenTransfer
    /// !!! IMPORTANT The Aave governance is considered a trustable contract, being its responsibility
    /// to control all potential reentrancies by calling back the AaveToken
    ITransferHook public _aaveGovernance;

    bytes32 public DOMAIN_SEPARATOR;
    bytes public constant EIP712_REVISION = bytes("1");
    bytes32 internal constant EIP712_DOMAIN = keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");
    bytes32 public constant PERMIT_TYPEHASH = keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");

    event SnapshotDone(address owner, uint128 oldValue, uint128 newValue);

    constructor() ERC20(NAME, SYMBOL) public {}

    /**
    * @dev initializes the contract upon assignment to the InitializableAdminUpgradeabilityProxy
    * @param migrator the address of the LEND -> AAVE migration contract
    * @param distributor the address of the AAVE distribution contract
    */
    function initialize(
        address migrator,
        address distributor,
        ITransferHook aaveGovernance
    ) external initializer {

        uint256 chainId;

        //solium-disable-next-line
        assembly {
            chainId := chainid()
        }

        DOMAIN_SEPARATOR = keccak256(abi.encode(
            EIP712_DOMAIN,
            keccak256(bytes(NAME)),
            keccak256(EIP712_REVISION),
            chainId,
            address(this)
        ));
        _name = NAME;
        _symbol = SYMBOL;
        _setupDecimals(DECIMALS);
        _aaveGovernance = aaveGovernance;
        _mint(migrator, MIGRATION_AMOUNT);
        _mint(distributor, DISTRIBUTION_AMOUNT);
    }

    /**
    * @dev implements the permit function as for https://github.com/ethereum/EIPs/blob/8a34d644aacf0f9f8f00815307fd7dd5da07655f/EIPS/eip-2612.md
    * @param owner the owner of the funds
    * @param spender the spender
    * @param value the amount
    * @param deadline the deadline timestamp, type(uint256).max for no deadline
    * @param v signature param
    * @param s signature param
    * @param r signature param
    */

    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external {
        require(owner != address(0), "INVALID_OWNER");
        //solium-disable-next-line
        require(block.timestamp <= deadline, "INVALID_EXPIRATION");
        uint256 currentValidNonce = _nonces[owner];
        bytes32 digest = keccak256(
                abi.encodePacked(
                    "\x19\x01",
                    DOMAIN_SEPARATOR,
                    keccak256(
                        abi.encode(PERMIT_TYPEHASH, owner, spender, value, currentValidNonce, deadline))
                    )
        );

        require(owner == ecrecover(digest, v, r, s), "INVALID_SIGNATURE");
        _nonces[owner] = currentValidNonce.add(1);
        _approve(owner, spender, value);
    }

    /**
    * @dev returns the revision of the implementation contract
    */
    function getRevision() internal pure override returns (uint256) {
        return REVISION;
    }

    /**
    * @dev Writes a snapshot for an owner of tokens
    * @param owner The owner of the tokens
    * @param oldValue The value before the operation that is gonna be executed after the snapshot
    * @param newValue The value after the operation
    */
    function _writeSnapshot(address owner, uint128 oldValue, uint128 newValue) internal {
        uint128 currentBlock = uint128(block.number);

        uint256 ownerCountOfSnapshots = _countsSnapshots[owner];
        mapping (uint256 => Snapshot) storage snapshotsOwner = _snapshots[owner];

        // Doing multiple operations in the same block
        if (ownerCountOfSnapshots != 0 && snapshotsOwner[ownerCountOfSnapshots.sub(1)].blockNumber == currentBlock) {
            snapshotsOwner[ownerCountOfSnapshots.sub(1)].value = newValue;
        } else {
            snapshotsOwner[ownerCountOfSnapshots] = Snapshot(currentBlock, newValue);
            _countsSnapshots[owner] = ownerCountOfSnapshots.add(1);
        }

        emit SnapshotDone(owner, oldValue, newValue);
    }

    /**
    * @dev Writes a snapshot before any operation involving transfer of value: _transfer, _mint and _burn
    * - On _transfer, it writes snapshots for both "from" and "to"
    * - On _mint, only for _to
    * - On _burn, only for _from
    * @param from the from address
    * @param to the to address
    * @param amount the amount to transfer
    */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal override {
        if (from == to) {
            return;
        }

        if (from != address(0)) {
            uint256 fromBalance = balanceOf(from);
            _writeSnapshot(from, uint128(fromBalance), uint128(fromBalance.sub(amount)));
        }
        if (to != address(0)) {
            uint256 toBalance = balanceOf(to);
            _writeSnapshot(to, uint128(toBalance), uint128(toBalance.add(amount)));
        }

        // caching the aave governance address to avoid multiple state loads
        ITransferHook aaveGovernance = _aaveGovernance;
        if (aaveGovernance != ITransferHook(0)) {
            aaveGovernance.onTransfer(from, to, amount);
        }
    }
}// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.10;

/**
 * @title VersionedInitializable
 *
 * @dev Helper contract to support initializer functions. To use it, replace
 * the constructor with a function that has the `initializer` modifier.
 * WARNING: Unlike constructors, initializer functions must be manually
 * invoked. This applies both to deploying an Initializable contract, as well
 * as extending an Initializable contract via inheritance.
 * WARNING: When used with inheritance, manual care must be taken to not invoke
 * a parent initializer twice, or ensure that all initializers are idempotent,
 * because this is not dealt with automatically as with constructors.
 *
 * @author Aave, inspired by the OpenZeppelin Initializable contract
 */
abstract contract VersionedInitializable {
    /**
   * @dev Indicates that the contract has been initialized.
   */
    uint256 internal lastInitializedRevision = 0;

   /**
   * @dev Modifier to use in the initializer function of a contract.
   */
    modifier initializer() {
        uint256 revision = getRevision();
        require(revision > lastInitializedRevision, "Contract instance has already been initialized");

        lastInitializedRevision = revision;

        _;

    }

    /// @dev returns the revision number of the contract.
    /// Needs to be defined in the inherited class as a constant.
    function getRevision() internal pure virtual returns(uint256);


    // Reserved storage space to allow for layout changes in the future.
    uint256[50] private ______gap;
}
// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.10;

import {IERC20} from "../interfaces/IERC20.sol";
import {SafeMath} from "../open-zeppelin/SafeMath.sol";
import {VersionedInitializable} from "../utils/VersionedInitializable.sol";


/**
* @title LendToAaveMigrator
* @notice This contract implements the migration from LEND to AAVE token
* @author Aave 
*/
contract LendToAaveMigrator is VersionedInitializable {
    using SafeMath for uint256;

    IERC20 public immutable AAVE;
    IERC20 public immutable LEND;
    uint256 public immutable LEND_AAVE_RATIO;
    uint256 public constant REVISION = 1;
    
    uint256 public _totalLendMigrated;

    /**
    * @dev emitted on migration
    * @param sender the caller of the migration
    * @param amount the amount being migrated
    */
    event LendMigrated(address indexed sender, uint256 indexed amount);

    /**
    * @param aave the address of the AAVE token
    * @param lend the address of the LEND token
    * @param lendAaveRatio the exchange rate between LEND and AAVE 
     */
    constructor(IERC20 aave, IERC20 lend, uint256 lendAaveRatio) public {
        AAVE = aave;
        LEND = lend;
        LEND_AAVE_RATIO = lendAaveRatio;
    }

    /**
    * @dev initializes the implementation
    */
    function initialize() public initializer {
    }

    /**
    * @dev returns true if the migration started
    */
    function migrationStarted() external view returns(bool) {
        return lastInitializedRevision != 0;
    }


    /**
    * @dev executes the migration from LEND to AAVE. Users need to give allowance to this contract to transfer LEND before executing
    * this transaction.
    * @param amount the amount of LEND to be migrated
    */
    function migrateFromLEND(uint256 amount) external {
        require(lastInitializedRevision != 0, "MIGRATION_NOT_STARTED");

        _totalLendMigrated = _totalLendMigrated.add(amount);
        LEND.transferFrom(msg.sender, address(this), amount);
        AAVE.transfer(msg.sender, amount.div(LEND_AAVE_RATIO));
        emit LendMigrated(msg.sender, amount);
    }

    /**
    * @dev returns the implementation revision
    * @return the implementation revision
    */
    function getRevision() internal pure override returns (uint256) {
        return REVISION;
    }

}// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.10;

import "../interfaces/IERC20.sol";

contract DoubleTransferHelper {

    IERC20 public immutable AAVE;

    constructor(IERC20 aave) public {
        AAVE = aave;
    }

    function doubleSend(address to, uint256 amount1, uint256 amount2) external {
        AAVE.transfer(to, amount1);
        AAVE.transfer(to, amount2);
    }
}// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.10;

import "../open-zeppelin/ERC20.sol";

/**
 * @title ERC20Mintable
 * @dev ERC20 minting logic
 */
contract MintableErc20 is ERC20 {
    constructor(string memory name, string memory symbol, uint8 decimals) ERC20(name, symbol) public {
        _setupDecimals(decimals);
    }
    /**
     * @dev Function to mint tokens
     * @param value The amount of tokens to mint.
     * @return A boolean that indicates if the operation was successful.
     */
    function mint(uint256 value) public returns (bool) {
        _mint(msg.sender, value);
        return true;
    }
}
// SPDX-License-Identifier: agpl-3.0
pragma solidity 0.6.10;

import {ITransferHook} from "../interfaces/ITransferHook.sol";

contract MockTransferHook is ITransferHook {
    event MockHookEvent();

    function onTransfer(address from, address to, uint256 amount) external override {
        emit MockHookEvent();
    }
} < 

InitializableAdminUpgradeabilityProxy ABI

[{"anonymous":false,"inputs":[{"indexed":false,"internalType":"address","name":"previousAdmin","type":"address"},{"indexed":false,"internalType":"address","name":"newAdmin","type":"address"}],"name":"AdminChanged","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"implementation","type":"address"}],"name":"Upgraded","type":"event"},{"stateMutability":"payable","type":"fallback"},{"inputs":[],"name":"admin","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"newAdmin","type":"address"}],"name":"changeAdmin","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"implementation","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"_logic","type":"address"},{"internalType":"address","name":"_admin","type":"address"},{"internalType":"bytes","name":"_data","type":"bytes"}],"name":"initialize","outputs":[],"stateMutability":"payable","type":"function"},{"inputs":[{"internalType":"address","name":"_logic","type":"address"},{"internalType":"bytes","name":"_data","type":"bytes"}],"name":"initialize","outputs":[],"stateMutability":"payable","type":"function"},{"inputs":[{"internalType":"address","name":"newImplementation","type":"address"}],"name":"upgradeTo","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"newImplementation","type":"address"},{"internalType":"bytes","name":"data","type":"bytes"}],"name":"upgradeToAndCall","outputs":[],"stateMutability":"payable","type":"function"}]
[{"anonymous":false,"inputs":[{"indexed":false,"internalType":"address","name":"previousAdmin","type":"address"},{"indexed":false,"internalType":"address","name":"newAdmin","type":"address"}],"name":"AdminChanged","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"implementation","type":"address"}],"name":"Upgraded","type":"event"},{"stateMutability":"payable","type":"fallback"},{"inputs":[],"name":"admin","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"newAdmin","type":"address"}],"name":"changeAdmin","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"implementation","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"_logic","type":"address"},{"internalType":"address","name":"_admin","type":"address"},{"internalType":"bytes","name":"_data","type":"bytes"}],"name":"initialize","outputs":[],"stateMutability":"payable","type":"function"},{"inputs":[{"internalType":"address","name":"_logic","type":"address"},{"internalType":"bytes","name":"_data","type":"bytes"}],"name":"initialize","outputs":[],"stateMutability":"payable","type":"function"},{"inputs":[{"internalType":"address","name":"newImplementation","type":"address"}],"name":"upgradeTo","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"newImplementation","type":"address"},{"internalType":"bytes","name":"data","type":"bytes"}],"name":"upgradeToAndCall","outputs":[],"stateMutability":"payable","type":"function"}]

InitializableAdminUpgradeabilityProxy Bytecode

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

Check out more smart contracts

Build blockchain magic with Alchemy

Alchemy combines the most powerful web3 developer products and tools with resources, community and legendary support.