Contract Name:
AssetOfferLoan
Contract Source Code:
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (access/AccessControl.sol)
pragma solidity ^0.8.0;
import "./IAccessControl.sol";
import "../utils/Context.sol";
import "../utils/Strings.sol";
import "../utils/introspection/ERC165.sol";
/**
* @dev Contract module that allows children to implement role-based access
* control mechanisms. This is a lightweight version that doesn't allow enumerating role
* members except through off-chain means by accessing the contract event logs. Some
* applications may benefit from on-chain enumerability, for those cases see
* {AccessControlEnumerable}.
*
* Roles are referred to by their `bytes32` identifier. These should be exposed
* in the external API and be unique. The best way to achieve this is by
* using `public constant` hash digests:
*
* ```solidity
* bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
* ```
*
* Roles can be used to represent a set of permissions. To restrict access to a
* function call, use {hasRole}:
*
* ```solidity
* function foo() public {
* require(hasRole(MY_ROLE, msg.sender));
* ...
* }
* ```
*
* Roles can be granted and revoked dynamically via the {grantRole} and
* {revokeRole} functions. Each role has an associated admin role, and only
* accounts that have a role's admin role can call {grantRole} and {revokeRole}.
*
* By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
* that only accounts with this role will be able to grant or revoke other
* roles. More complex role relationships can be created by using
* {_setRoleAdmin}.
*
* WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
* grant and revoke this role. Extra precautions should be taken to secure
* accounts that have been granted it. We recommend using {AccessControlDefaultAdminRules}
* to enforce additional security measures for this role.
*/
abstract contract AccessControl is Context, IAccessControl, ERC165 {
struct RoleData {
mapping(address => bool) members;
bytes32 adminRole;
}
mapping(bytes32 => RoleData) private _roles;
bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
/**
* @dev Modifier that checks that an account has a specific role. Reverts
* with a standardized message including the required role.
*
* The format of the revert reason is given by the following regular expression:
*
* /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
*
* _Available since v4.1._
*/
modifier onlyRole(bytes32 role) {
_checkRole(role);
_;
}
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId);
}
/**
* @dev Returns `true` if `account` has been granted `role`.
*/
function hasRole(bytes32 role, address account) public view virtual override returns (bool) {
return _roles[role].members[account];
}
/**
* @dev Revert with a standard message if `_msgSender()` is missing `role`.
* Overriding this function changes the behavior of the {onlyRole} modifier.
*
* Format of the revert message is described in {_checkRole}.
*
* _Available since v4.6._
*/
function _checkRole(bytes32 role) internal view virtual {
_checkRole(role, _msgSender());
}
/**
* @dev Revert with a standard message if `account` is missing `role`.
*
* The format of the revert reason is given by the following regular expression:
*
* /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
*/
function _checkRole(bytes32 role, address account) internal view virtual {
if (!hasRole(role, account)) {
revert(
string(
abi.encodePacked(
"AccessControl: account ",
Strings.toHexString(account),
" is missing role ",
Strings.toHexString(uint256(role), 32)
)
)
);
}
}
/**
* @dev Returns the admin role that controls `role`. See {grantRole} and
* {revokeRole}.
*
* To change a role's admin, use {_setRoleAdmin}.
*/
function getRoleAdmin(bytes32 role) public view virtual override returns (bytes32) {
return _roles[role].adminRole;
}
/**
* @dev Grants `role` to `account`.
*
* If `account` had not been already granted `role`, emits a {RoleGranted}
* event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*
* May emit a {RoleGranted} event.
*/
function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
_grantRole(role, account);
}
/**
* @dev Revokes `role` from `account`.
*
* If `account` had been granted `role`, emits a {RoleRevoked} event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*
* May emit a {RoleRevoked} event.
*/
function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
_revokeRole(role, account);
}
/**
* @dev Revokes `role` from the calling account.
*
* Roles are often managed via {grantRole} and {revokeRole}: this function's
* purpose is to provide a mechanism for accounts to lose their privileges
* if they are compromised (such as when a trusted device is misplaced).
*
* If the calling account had been revoked `role`, emits a {RoleRevoked}
* event.
*
* Requirements:
*
* - the caller must be `account`.
*
* May emit a {RoleRevoked} event.
*/
function renounceRole(bytes32 role, address account) public virtual override {
require(account == _msgSender(), "AccessControl: can only renounce roles for self");
_revokeRole(role, account);
}
/**
* @dev Grants `role` to `account`.
*
* If `account` had not been already granted `role`, emits a {RoleGranted}
* event. Note that unlike {grantRole}, this function doesn't perform any
* checks on the calling account.
*
* May emit a {RoleGranted} event.
*
* [WARNING]
* ====
* This function should only be called from the constructor when setting
* up the initial roles for the system.
*
* Using this function in any other way is effectively circumventing the admin
* system imposed by {AccessControl}.
* ====
*
* NOTE: This function is deprecated in favor of {_grantRole}.
*/
function _setupRole(bytes32 role, address account) internal virtual {
_grantRole(role, account);
}
/**
* @dev Sets `adminRole` as ``role``'s admin role.
*
* Emits a {RoleAdminChanged} event.
*/
function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
bytes32 previousAdminRole = getRoleAdmin(role);
_roles[role].adminRole = adminRole;
emit RoleAdminChanged(role, previousAdminRole, adminRole);
}
/**
* @dev Grants `role` to `account`.
*
* Internal function without access restriction.
*
* May emit a {RoleGranted} event.
*/
function _grantRole(bytes32 role, address account) internal virtual {
if (!hasRole(role, account)) {
_roles[role].members[account] = true;
emit RoleGranted(role, account, _msgSender());
}
}
/**
* @dev Revokes `role` from `account`.
*
* Internal function without access restriction.
*
* May emit a {RoleRevoked} event.
*/
function _revokeRole(bytes32 role, address account) internal virtual {
if (hasRole(role, account)) {
_roles[role].members[account] = false;
emit RoleRevoked(role, account, _msgSender());
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)
pragma solidity ^0.8.0;
/**
* @dev External interface of AccessControl declared to support ERC165 detection.
*/
interface IAccessControl {
/**
* @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
*
* `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
* {RoleAdminChanged} not being emitted signaling this.
*
* _Available since v3.1._
*/
event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
/**
* @dev Emitted when `account` is granted `role`.
*
* `sender` is the account that originated the contract call, an admin role
* bearer except when using {AccessControl-_setupRole}.
*/
event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
/**
* @dev Emitted when `account` is revoked `role`.
*
* `sender` is the account that originated the contract call:
* - if using `revokeRole`, it is the admin role bearer
* - if using `renounceRole`, it is the role bearer (i.e. `account`)
*/
event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
/**
* @dev Returns `true` if `account` has been granted `role`.
*/
function hasRole(bytes32 role, address account) external view returns (bool);
/**
* @dev Returns the admin role that controls `role`. See {grantRole} and
* {revokeRole}.
*
* To change a role's admin, use {AccessControl-_setRoleAdmin}.
*/
function getRoleAdmin(bytes32 role) external view returns (bytes32);
/**
* @dev Grants `role` to `account`.
*
* If `account` had not been already granted `role`, emits a {RoleGranted}
* event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*/
function grantRole(bytes32 role, address account) external;
/**
* @dev Revokes `role` from `account`.
*
* If `account` had been granted `role`, emits a {RoleRevoked} event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*/
function revokeRole(bytes32 role, address account) external;
/**
* @dev Revokes `role` from the calling account.
*
* Roles are often managed via {grantRole} and {revokeRole}: this function's
* purpose is to provide a mechanism for accounts to lose their privileges
* if they are compromised (such as when a trusted device is misplaced).
*
* If the calling account had been granted `role`, emits a {RoleRevoked}
* event.
*
* Requirements:
*
* - the caller must be `account`.
*/
function renounceRole(bytes32 role, address account) external;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (interfaces/IERC1271.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC1271 standard signature validation method for
* contracts as defined in https://eips.ethereum.org/EIPS/eip-1271[ERC-1271].
*
* _Available since v4.1._
*/
interface IERC1271 {
/**
* @dev Should return whether the signature provided is valid for the provided data
* @param hash Hash of the data to be signed
* @param signature Signature byte array associated with _data
*/
function isValidSignature(bytes32 hash, bytes memory signature) external view returns (bytes4 magicValue);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (proxy/Clones.sol)
pragma solidity ^0.8.0;
/**
* @dev https://eips.ethereum.org/EIPS/eip-1167[EIP 1167] is a standard for
* deploying minimal proxy contracts, also known as "clones".
*
* > To simply and cheaply clone contract functionality in an immutable way, this standard specifies
* > a minimal bytecode implementation that delegates all calls to a known, fixed address.
*
* The library includes functions to deploy a proxy using either `create` (traditional deployment) or `create2`
* (salted deterministic deployment). It also includes functions to predict the addresses of clones deployed using the
* deterministic method.
*
* _Available since v3.4._
*/
library Clones {
/**
* @dev Deploys and returns the address of a clone that mimics the behaviour of `implementation`.
*
* This function uses the create opcode, which should never revert.
*/
function clone(address implementation) internal returns (address instance) {
/// @solidity memory-safe-assembly
assembly {
// Cleans the upper 96 bits of the `implementation` word, then packs the first 3 bytes
// of the `implementation` address with the bytecode before the address.
mstore(0x00, or(shr(0xe8, shl(0x60, implementation)), 0x3d602d80600a3d3981f3363d3d373d3d3d363d73000000))
// Packs the remaining 17 bytes of `implementation` with the bytecode after the address.
mstore(0x20, or(shl(0x78, implementation), 0x5af43d82803e903d91602b57fd5bf3))
instance := create(0, 0x09, 0x37)
}
require(instance != address(0), "ERC1167: create failed");
}
/**
* @dev Deploys and returns the address of a clone that mimics the behaviour of `implementation`.
*
* This function uses the create2 opcode and a `salt` to deterministically deploy
* the clone. Using the same `implementation` and `salt` multiple time will revert, since
* the clones cannot be deployed twice at the same address.
*/
function cloneDeterministic(address implementation, bytes32 salt) internal returns (address instance) {
/// @solidity memory-safe-assembly
assembly {
// Cleans the upper 96 bits of the `implementation` word, then packs the first 3 bytes
// of the `implementation` address with the bytecode before the address.
mstore(0x00, or(shr(0xe8, shl(0x60, implementation)), 0x3d602d80600a3d3981f3363d3d373d3d3d363d73000000))
// Packs the remaining 17 bytes of `implementation` with the bytecode after the address.
mstore(0x20, or(shl(0x78, implementation), 0x5af43d82803e903d91602b57fd5bf3))
instance := create2(0, 0x09, 0x37, salt)
}
require(instance != address(0), "ERC1167: create2 failed");
}
/**
* @dev Computes the address of a clone deployed using {Clones-cloneDeterministic}.
*/
function predictDeterministicAddress(
address implementation,
bytes32 salt,
address deployer
) internal pure returns (address predicted) {
/// @solidity memory-safe-assembly
assembly {
let ptr := mload(0x40)
mstore(add(ptr, 0x38), deployer)
mstore(add(ptr, 0x24), 0x5af43d82803e903d91602b57fd5bf3ff)
mstore(add(ptr, 0x14), implementation)
mstore(ptr, 0x3d602d80600a3d3981f3363d3d373d3d3d363d73)
mstore(add(ptr, 0x58), salt)
mstore(add(ptr, 0x78), keccak256(add(ptr, 0x0c), 0x37))
predicted := keccak256(add(ptr, 0x43), 0x55)
}
}
/**
* @dev Computes the address of a clone deployed using {Clones-cloneDeterministic}.
*/
function predictDeterministicAddress(
address implementation,
bytes32 salt
) internal view returns (address predicted) {
return predictDeterministicAddress(implementation, salt, address(this));
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (proxy/utils/Initializable.sol)
pragma solidity ^0.8.2;
import "../../utils/Address.sol";
/**
* @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
* behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
* external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
* function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
*
* The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
* reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
* case an upgrade adds a module that needs to be initialized.
*
* For example:
*
* [.hljs-theme-light.nopadding]
* ```solidity
* contract MyToken is ERC20Upgradeable {
* function initialize() initializer public {
* __ERC20_init("MyToken", "MTK");
* }
* }
*
* contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
* function initializeV2() reinitializer(2) public {
* __ERC20Permit_init("MyToken");
* }
* }
* ```
*
* TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
* possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
*
* CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
* that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
*
* [CAUTION]
* ====
* Avoid leaving a contract uninitialized.
*
* An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
* contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
* the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
*
* [.hljs-theme-light.nopadding]
* ```
* /// @custom:oz-upgrades-unsafe-allow constructor
* constructor() {
* _disableInitializers();
* }
* ```
* ====
*/
abstract contract Initializable {
/**
* @dev Indicates that the contract has been initialized.
* @custom:oz-retyped-from bool
*/
uint8 private _initialized;
/**
* @dev Indicates that the contract is in the process of being initialized.
*/
bool private _initializing;
/**
* @dev Triggered when the contract has been initialized or reinitialized.
*/
event Initialized(uint8 version);
/**
* @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
* `onlyInitializing` functions can be used to initialize parent contracts.
*
* Similar to `reinitializer(1)`, except that functions marked with `initializer` can be nested in the context of a
* constructor.
*
* Emits an {Initialized} event.
*/
modifier initializer() {
bool isTopLevelCall = !_initializing;
require(
(isTopLevelCall && _initialized < 1) || (!Address.isContract(address(this)) && _initialized == 1),
"Initializable: contract is already initialized"
);
_initialized = 1;
if (isTopLevelCall) {
_initializing = true;
}
_;
if (isTopLevelCall) {
_initializing = false;
emit Initialized(1);
}
}
/**
* @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
* contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
* used to initialize parent contracts.
*
* A reinitializer may be used after the original initialization step. This is essential to configure modules that
* are added through upgrades and that require initialization.
*
* When `version` is 1, this modifier is similar to `initializer`, except that functions marked with `reinitializer`
* cannot be nested. If one is invoked in the context of another, execution will revert.
*
* Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
* a contract, executing them in the right order is up to the developer or operator.
*
* WARNING: setting the version to 255 will prevent any future reinitialization.
*
* Emits an {Initialized} event.
*/
modifier reinitializer(uint8 version) {
require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
_initialized = version;
_initializing = true;
_;
_initializing = false;
emit Initialized(version);
}
/**
* @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
* {initializer} and {reinitializer} modifiers, directly or indirectly.
*/
modifier onlyInitializing() {
require(_initializing, "Initializable: contract is not initializing");
_;
}
/**
* @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
* Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
* to any version. It is recommended to use this to lock implementation contracts that are designed to be called
* through proxies.
*
* Emits an {Initialized} event the first time it is successfully executed.
*/
function _disableInitializers() internal virtual {
require(!_initializing, "Initializable: contract is initializing");
if (_initialized != type(uint8).max) {
_initialized = type(uint8).max;
emit Initialized(type(uint8).max);
}
}
/**
* @dev Returns the highest version that has been initialized. See {reinitializer}.
*/
function _getInitializedVersion() internal view returns (uint8) {
return _initialized;
}
/**
* @dev Returns `true` if the contract is currently initializing. See {onlyInitializing}.
*/
function _isInitializing() internal view returns (bool) {
return _initializing;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (security/Pausable.sol)
pragma solidity ^0.8.0;
import "../utils/Context.sol";
/**
* @dev Contract module which allows children to implement an emergency stop
* mechanism that can be triggered by an authorized account.
*
* This module is used through inheritance. It will make available the
* modifiers `whenNotPaused` and `whenPaused`, which can be applied to
* the functions of your contract. Note that they will not be pausable by
* simply including this module, only once the modifiers are put in place.
*/
abstract contract Pausable is Context {
/**
* @dev Emitted when the pause is triggered by `account`.
*/
event Paused(address account);
/**
* @dev Emitted when the pause is lifted by `account`.
*/
event Unpaused(address account);
bool private _paused;
/**
* @dev Initializes the contract in unpaused state.
*/
constructor() {
_paused = false;
}
/**
* @dev Modifier to make a function callable only when the contract is not paused.
*
* Requirements:
*
* - The contract must not be paused.
*/
modifier whenNotPaused() {
_requireNotPaused();
_;
}
/**
* @dev Modifier to make a function callable only when the contract is paused.
*
* Requirements:
*
* - The contract must be paused.
*/
modifier whenPaused() {
_requirePaused();
_;
}
/**
* @dev Returns true if the contract is paused, and false otherwise.
*/
function paused() public view virtual returns (bool) {
return _paused;
}
/**
* @dev Throws if the contract is paused.
*/
function _requireNotPaused() internal view virtual {
require(!paused(), "Pausable: paused");
}
/**
* @dev Throws if the contract is not paused.
*/
function _requirePaused() internal view virtual {
require(paused(), "Pausable: not paused");
}
/**
* @dev Triggers stopped state.
*
* Requirements:
*
* - The contract must not be paused.
*/
function _pause() internal virtual whenNotPaused {
_paused = true;
emit Paused(_msgSender());
}
/**
* @dev Returns to normal state.
*
* Requirements:
*
* - The contract must be paused.
*/
function _unpause() internal virtual whenPaused {
_paused = false;
emit Unpaused(_msgSender());
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (security/ReentrancyGuard.sol)
pragma solidity ^0.8.0;
/**
* @dev Contract module that helps prevent reentrant calls to a function.
*
* Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
* available, which can be applied to functions to make sure there are no nested
* (reentrant) calls to them.
*
* Note that because there is a single `nonReentrant` guard, functions marked as
* `nonReentrant` may not call one another. This can be worked around by making
* those functions `private`, and then adding `external` `nonReentrant` entry
* points to them.
*
* TIP: If you would like to learn more about reentrancy and alternative ways
* to protect against it, check out our blog post
* https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
*/
abstract contract ReentrancyGuard {
// Booleans are more expensive than uint256 or any type that takes up a full
// word because each write operation emits an extra SLOAD to first read the
// slot's contents, replace the bits taken up by the boolean, and then write
// back. This is the compiler's defense against contract upgrades and
// pointer aliasing, and it cannot be disabled.
// The values being non-zero value makes deployment a bit more expensive,
// but in exchange the refund on every call to nonReentrant will be lower in
// amount. Since refunds are capped to a percentage of the total
// transaction's gas, it is best to keep them low in cases like this one, to
// increase the likelihood of the full refund coming into effect.
uint256 private constant _NOT_ENTERED = 1;
uint256 private constant _ENTERED = 2;
uint256 private _status;
constructor() {
_status = _NOT_ENTERED;
}
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* Calling a `nonReentrant` function from another `nonReentrant`
* function is not supported. It is possible to prevent this from happening
* by making the `nonReentrant` function external, and making it call a
* `private` function that does the actual work.
*/
modifier nonReentrant() {
_nonReentrantBefore();
_;
_nonReentrantAfter();
}
function _nonReentrantBefore() private {
// On the first call to nonReentrant, _status will be _NOT_ENTERED
require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
// Any calls to nonReentrant after this point will fail
_status = _ENTERED;
}
function _nonReentrantAfter() private {
// By storing the original value once again, a refund is triggered (see
// https://eips.ethereum.org/EIPS/eip-2200)
_status = _NOT_ENTERED;
}
/**
* @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
* `nonReentrant` function in the call stack.
*/
function _reentrancyGuardEntered() internal view returns (bool) {
return _status == _ENTERED;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC1155/IERC1155Receiver.sol)
pragma solidity ^0.8.0;
import "../../utils/introspection/IERC165.sol";
/**
* @dev _Available since v3.1._
*/
interface IERC1155Receiver is IERC165 {
/**
* @dev Handles the receipt of a single ERC1155 token type. This function is
* called at the end of a `safeTransferFrom` after the balance has been updated.
*
* NOTE: To accept the transfer, this must return
* `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))`
* (i.e. 0xf23a6e61, or its own function selector).
*
* @param operator The address which initiated the transfer (i.e. msg.sender)
* @param from The address which previously owned the token
* @param id The ID of the token being transferred
* @param value The amount of tokens being transferred
* @param data Additional data with no specified format
* @return `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))` if transfer is allowed
*/
function onERC1155Received(
address operator,
address from,
uint256 id,
uint256 value,
bytes calldata data
) external returns (bytes4);
/**
* @dev Handles the receipt of a multiple ERC1155 token types. This function
* is called at the end of a `safeBatchTransferFrom` after the balances have
* been updated.
*
* NOTE: To accept the transfer(s), this must return
* `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))`
* (i.e. 0xbc197c81, or its own function selector).
*
* @param operator The address which initiated the batch transfer (i.e. msg.sender)
* @param from The address which previously owned the token
* @param ids An array containing ids of each token being transferred (order and length must match values array)
* @param values An array containing amounts of each token being transferred (order and length must match ids array)
* @param data Additional data with no specified format
* @return `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))` if transfer is allowed
*/
function onERC1155BatchReceived(
address operator,
address from,
uint256[] calldata ids,
uint256[] calldata values,
bytes calldata data
) external returns (bytes4);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/extensions/IERC20Permit.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
* https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
*
* Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
* presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
* need to send a transaction, and thus is not required to hold Ether at all.
*/
interface IERC20Permit {
/**
* @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
* given ``owner``'s signed approval.
*
* IMPORTANT: The same issues {IERC20-approve} has related to transaction
* ordering also apply here.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `deadline` must be a timestamp in the future.
* - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
* over the EIP712-formatted function arguments.
* - the signature must use ``owner``'s current nonce (see {nonces}).
*
* For more information on the signature format, see the
* https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
* section].
*/
function permit(
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) external;
/**
* @dev Returns the current nonce for `owner`. This value must be
* included whenever a signature is generated for {permit}.
*
* Every successful call to {permit} increases ``owner``'s nonce by one. This
* prevents a signature from being used multiple times.
*/
function nonces(address owner) external view returns (uint256);
/**
* @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
*/
// solhint-disable-next-line func-name-mixedcase
function DOMAIN_SEPARATOR() external view returns (bytes32);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @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);
/**
* @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 `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, 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 `from` to `to` 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 from, address to, uint256 amount) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.3) (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
import "../extensions/IERC20Permit.sol";
import "../../../utils/Address.sol";
/**
* @title SafeERC20
* @dev Wrappers around ERC20 operations that throw on failure (when the token
* contract returns false). Tokens that return no value (and instead revert or
* throw on failure) are also supported, non-reverting calls are assumed to be
* successful.
* To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeERC20 {
using Address for address;
/**
* @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeTransfer(IERC20 token, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
/**
* @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
* calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
*/
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
/**
* @dev Deprecated. This function has issues similar to the ones found in
* {IERC20-approve}, and its usage is discouraged.
*
* Whenever possible, use {safeIncreaseAllowance} and
* {safeDecreaseAllowance} instead.
*/
function safeApprove(IERC20 token, address spender, uint256 value) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
require(
(value == 0) || (token.allowance(address(this), spender) == 0),
"SafeERC20: approve from non-zero to non-zero allowance"
);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
/**
* @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 oldAllowance = token.allowance(address(this), spender);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance + value));
}
/**
* @dev Decrease the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
unchecked {
uint256 oldAllowance = token.allowance(address(this), spender);
require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, oldAllowance - value));
}
}
/**
* @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
* to be set to zero before setting it to a non-zero value, such as USDT.
*/
function forceApprove(IERC20 token, address spender, uint256 value) internal {
bytes memory approvalCall = abi.encodeWithSelector(token.approve.selector, spender, value);
if (!_callOptionalReturnBool(token, approvalCall)) {
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, 0));
_callOptionalReturn(token, approvalCall);
}
}
/**
* @dev Use a ERC-2612 signature to set the `owner` approval toward `spender` on `token`.
* Revert on invalid signature.
*/
function safePermit(
IERC20Permit token,
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) internal {
uint256 nonceBefore = token.nonces(owner);
token.permit(owner, spender, value, deadline, v, r, s);
uint256 nonceAfter = token.nonces(owner);
require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function _callOptionalReturn(IERC20 token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. We use {Address-functionCall} to perform this call, which verifies that
// the target address contains contract code and also asserts for success in the low-level call.
bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
require(returndata.length == 0 || abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*
* This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead.
*/
function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. We cannot use {Address-functionCall} here since this should return false
// and not revert is the subcall reverts.
(bool success, bytes memory returndata) = address(token).call(data);
return
success && (returndata.length == 0 || abi.decode(returndata, (bool))) && Address.isContract(address(token));
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC721/ERC721.sol)
pragma solidity ^0.8.0;
import "./IERC721.sol";
import "./IERC721Receiver.sol";
import "./extensions/IERC721Metadata.sol";
import "../../utils/Address.sol";
import "../../utils/Context.sol";
import "../../utils/Strings.sol";
import "../../utils/introspection/ERC165.sol";
/**
* @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
* the Metadata extension, but not including the Enumerable extension, which is available separately as
* {ERC721Enumerable}.
*/
contract ERC721 is Context, ERC165, IERC721, IERC721Metadata {
using Address for address;
using Strings for uint256;
// Token name
string private _name;
// Token symbol
string private _symbol;
// Mapping from token ID to owner address
mapping(uint256 => address) private _owners;
// Mapping owner address to token count
mapping(address => uint256) private _balances;
// Mapping from token ID to approved address
mapping(uint256 => address) private _tokenApprovals;
// Mapping from owner to operator approvals
mapping(address => mapping(address => bool)) private _operatorApprovals;
/**
* @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
*/
constructor(string memory name_, string memory symbol_) {
_name = name_;
_symbol = symbol_;
}
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
return
interfaceId == type(IERC721).interfaceId ||
interfaceId == type(IERC721Metadata).interfaceId ||
super.supportsInterface(interfaceId);
}
/**
* @dev See {IERC721-balanceOf}.
*/
function balanceOf(address owner) public view virtual override returns (uint256) {
require(owner != address(0), "ERC721: address zero is not a valid owner");
return _balances[owner];
}
/**
* @dev See {IERC721-ownerOf}.
*/
function ownerOf(uint256 tokenId) public view virtual override returns (address) {
address owner = _ownerOf(tokenId);
require(owner != address(0), "ERC721: invalid token ID");
return owner;
}
/**
* @dev See {IERC721Metadata-name}.
*/
function name() public view virtual override returns (string memory) {
return _name;
}
/**
* @dev See {IERC721Metadata-symbol}.
*/
function symbol() public view virtual override returns (string memory) {
return _symbol;
}
/**
* @dev See {IERC721Metadata-tokenURI}.
*/
function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
_requireMinted(tokenId);
string memory baseURI = _baseURI();
return bytes(baseURI).length > 0 ? string(abi.encodePacked(baseURI, tokenId.toString())) : "";
}
/**
* @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
* token will be the concatenation of the `baseURI` and the `tokenId`. Empty
* by default, can be overridden in child contracts.
*/
function _baseURI() internal view virtual returns (string memory) {
return "";
}
/**
* @dev See {IERC721-approve}.
*/
function approve(address to, uint256 tokenId) public virtual override {
address owner = ERC721.ownerOf(tokenId);
require(to != owner, "ERC721: approval to current owner");
require(
_msgSender() == owner || isApprovedForAll(owner, _msgSender()),
"ERC721: approve caller is not token owner or approved for all"
);
_approve(to, tokenId);
}
/**
* @dev See {IERC721-getApproved}.
*/
function getApproved(uint256 tokenId) public view virtual override returns (address) {
_requireMinted(tokenId);
return _tokenApprovals[tokenId];
}
/**
* @dev See {IERC721-setApprovalForAll}.
*/
function setApprovalForAll(address operator, bool approved) public virtual override {
_setApprovalForAll(_msgSender(), operator, approved);
}
/**
* @dev See {IERC721-isApprovedForAll}.
*/
function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
return _operatorApprovals[owner][operator];
}
/**
* @dev See {IERC721-transferFrom}.
*/
function transferFrom(address from, address to, uint256 tokenId) public virtual override {
//solhint-disable-next-line max-line-length
require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner or approved");
_transfer(from, to, tokenId);
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/
function safeTransferFrom(address from, address to, uint256 tokenId) public virtual override {
safeTransferFrom(from, to, tokenId, "");
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/
function safeTransferFrom(address from, address to, uint256 tokenId, bytes memory data) public virtual override {
require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner or approved");
_safeTransfer(from, to, tokenId, data);
}
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
* are aware of the ERC721 protocol to prevent tokens from being forever locked.
*
* `data` is additional data, it has no specified format and it is sent in call to `to`.
*
* This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
* implement alternative mechanisms to perform token transfer, such as signature-based.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function _safeTransfer(address from, address to, uint256 tokenId, bytes memory data) internal virtual {
_transfer(from, to, tokenId);
require(_checkOnERC721Received(from, to, tokenId, data), "ERC721: transfer to non ERC721Receiver implementer");
}
/**
* @dev Returns the owner of the `tokenId`. Does NOT revert if token doesn't exist
*/
function _ownerOf(uint256 tokenId) internal view virtual returns (address) {
return _owners[tokenId];
}
/**
* @dev Returns whether `tokenId` exists.
*
* Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
*
* Tokens start existing when they are minted (`_mint`),
* and stop existing when they are burned (`_burn`).
*/
function _exists(uint256 tokenId) internal view virtual returns (bool) {
return _ownerOf(tokenId) != address(0);
}
/**
* @dev Returns whether `spender` is allowed to manage `tokenId`.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function _isApprovedOrOwner(address spender, uint256 tokenId) internal view virtual returns (bool) {
address owner = ERC721.ownerOf(tokenId);
return (spender == owner || isApprovedForAll(owner, spender) || getApproved(tokenId) == spender);
}
/**
* @dev Safely mints `tokenId` and transfers it to `to`.
*
* Requirements:
*
* - `tokenId` must not exist.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function _safeMint(address to, uint256 tokenId) internal virtual {
_safeMint(to, tokenId, "");
}
/**
* @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
* forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
*/
function _safeMint(address to, uint256 tokenId, bytes memory data) internal virtual {
_mint(to, tokenId);
require(
_checkOnERC721Received(address(0), to, tokenId, data),
"ERC721: transfer to non ERC721Receiver implementer"
);
}
/**
* @dev Mints `tokenId` and transfers it to `to`.
*
* WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
*
* Requirements:
*
* - `tokenId` must not exist.
* - `to` cannot be the zero address.
*
* Emits a {Transfer} event.
*/
function _mint(address to, uint256 tokenId) internal virtual {
require(to != address(0), "ERC721: mint to the zero address");
require(!_exists(tokenId), "ERC721: token already minted");
_beforeTokenTransfer(address(0), to, tokenId, 1);
// Check that tokenId was not minted by `_beforeTokenTransfer` hook
require(!_exists(tokenId), "ERC721: token already minted");
unchecked {
// Will not overflow unless all 2**256 token ids are minted to the same owner.
// Given that tokens are minted one by one, it is impossible in practice that
// this ever happens. Might change if we allow batch minting.
// The ERC fails to describe this case.
_balances[to] += 1;
}
_owners[tokenId] = to;
emit Transfer(address(0), to, tokenId);
_afterTokenTransfer(address(0), to, tokenId, 1);
}
/**
* @dev Destroys `tokenId`.
* The approval is cleared when the token is burned.
* This is an internal function that does not check if the sender is authorized to operate on the token.
*
* Requirements:
*
* - `tokenId` must exist.
*
* Emits a {Transfer} event.
*/
function _burn(uint256 tokenId) internal virtual {
address owner = ERC721.ownerOf(tokenId);
_beforeTokenTransfer(owner, address(0), tokenId, 1);
// Update ownership in case tokenId was transferred by `_beforeTokenTransfer` hook
owner = ERC721.ownerOf(tokenId);
// Clear approvals
delete _tokenApprovals[tokenId];
unchecked {
// Cannot overflow, as that would require more tokens to be burned/transferred
// out than the owner initially received through minting and transferring in.
_balances[owner] -= 1;
}
delete _owners[tokenId];
emit Transfer(owner, address(0), tokenId);
_afterTokenTransfer(owner, address(0), tokenId, 1);
}
/**
* @dev Transfers `tokenId` from `from` to `to`.
* As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
*
* Emits a {Transfer} event.
*/
function _transfer(address from, address to, uint256 tokenId) internal virtual {
require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer from incorrect owner");
require(to != address(0), "ERC721: transfer to the zero address");
_beforeTokenTransfer(from, to, tokenId, 1);
// Check that tokenId was not transferred by `_beforeTokenTransfer` hook
require(ERC721.ownerOf(tokenId) == from, "ERC721: transfer from incorrect owner");
// Clear approvals from the previous owner
delete _tokenApprovals[tokenId];
unchecked {
// `_balances[from]` cannot overflow for the same reason as described in `_burn`:
// `from`'s balance is the number of token held, which is at least one before the current
// transfer.
// `_balances[to]` could overflow in the conditions described in `_mint`. That would require
// all 2**256 token ids to be minted, which in practice is impossible.
_balances[from] -= 1;
_balances[to] += 1;
}
_owners[tokenId] = to;
emit Transfer(from, to, tokenId);
_afterTokenTransfer(from, to, tokenId, 1);
}
/**
* @dev Approve `to` to operate on `tokenId`
*
* Emits an {Approval} event.
*/
function _approve(address to, uint256 tokenId) internal virtual {
_tokenApprovals[tokenId] = to;
emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
}
/**
* @dev Approve `operator` to operate on all of `owner` tokens
*
* Emits an {ApprovalForAll} event.
*/
function _setApprovalForAll(address owner, address operator, bool approved) internal virtual {
require(owner != operator, "ERC721: approve to caller");
_operatorApprovals[owner][operator] = approved;
emit ApprovalForAll(owner, operator, approved);
}
/**
* @dev Reverts if the `tokenId` has not been minted yet.
*/
function _requireMinted(uint256 tokenId) internal view virtual {
require(_exists(tokenId), "ERC721: invalid token ID");
}
/**
* @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
* The call is not executed if the target address is not a contract.
*
* @param from address representing the previous owner of the given token ID
* @param to target address that will receive the tokens
* @param tokenId uint256 ID of the token to be transferred
* @param data bytes optional data to send along with the call
* @return bool whether the call correctly returned the expected magic value
*/
function _checkOnERC721Received(
address from,
address to,
uint256 tokenId,
bytes memory data
) private returns (bool) {
if (to.isContract()) {
try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, data) returns (bytes4 retval) {
return retval == IERC721Receiver.onERC721Received.selector;
} catch (bytes memory reason) {
if (reason.length == 0) {
revert("ERC721: transfer to non ERC721Receiver implementer");
} else {
/// @solidity memory-safe-assembly
assembly {
revert(add(32, reason), mload(reason))
}
}
}
} else {
return true;
}
}
/**
* @dev Hook that is called before any token transfer. This includes minting and burning. If {ERC721Consecutive} is
* used, the hook may be called as part of a consecutive (batch) mint, as indicated by `batchSize` greater than 1.
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, ``from``'s tokens will be transferred to `to`.
* - When `from` is zero, the tokens will be minted for `to`.
* - When `to` is zero, ``from``'s tokens will be burned.
* - `from` and `to` are never both zero.
* - `batchSize` is non-zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _beforeTokenTransfer(address from, address to, uint256 firstTokenId, uint256 batchSize) internal virtual {}
/**
* @dev Hook that is called after any token transfer. This includes minting and burning. If {ERC721Consecutive} is
* used, the hook may be called as part of a consecutive (batch) mint, as indicated by `batchSize` greater than 1.
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, ``from``'s tokens were transferred to `to`.
* - When `from` is zero, the tokens were minted for `to`.
* - When `to` is zero, ``from``'s tokens were burned.
* - `from` and `to` are never both zero.
* - `batchSize` is non-zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _afterTokenTransfer(address from, address to, uint256 firstTokenId, uint256 batchSize) internal virtual {}
/**
* @dev Unsafe write access to the balances, used by extensions that "mint" tokens using an {ownerOf} override.
*
* WARNING: Anyone calling this MUST ensure that the balances remain consistent with the ownership. The invariant
* being that for any address `a` the value returned by `balanceOf(a)` must be equal to the number of tokens such
* that `ownerOf(tokenId)` is `a`.
*/
// solhint-disable-next-line func-name-mixedcase
function __unsafe_increaseBalance(address account, uint256 amount) internal {
_balances[account] += amount;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC721/extensions/IERC721Metadata.sol)
pragma solidity ^0.8.0;
import "../IERC721.sol";
/**
* @title ERC-721 Non-Fungible Token Standard, optional metadata extension
* @dev See https://eips.ethereum.org/EIPS/eip-721
*/
interface IERC721Metadata is IERC721 {
/**
* @dev Returns the token collection name.
*/
function name() external view returns (string memory);
/**
* @dev Returns the token collection symbol.
*/
function symbol() external view returns (string memory);
/**
* @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
*/
function tokenURI(uint256 tokenId) external view returns (string memory);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC721/IERC721.sol)
pragma solidity ^0.8.0;
import "../../utils/introspection/IERC165.sol";
/**
* @dev Required interface of an ERC721 compliant contract.
*/
interface IERC721 is IERC165 {
/**
* @dev Emitted when `tokenId` token is transferred from `from` to `to`.
*/
event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
*/
event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
*/
event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
/**
* @dev Returns the number of tokens in ``owner``'s account.
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @dev Returns the owner of the `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function ownerOf(uint256 tokenId) external view returns (address owner);
/**
* @dev Safely transfers `tokenId` token from `from` to `to`.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(address from, address to, uint256 tokenId, bytes calldata data) external;
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
* are aware of the ERC721 protocol to prevent tokens from being forever locked.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must have been allowed to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(address from, address to, uint256 tokenId) external;
/**
* @dev Transfers `tokenId` token from `from` to `to`.
*
* WARNING: Note that the caller is responsible to confirm that the recipient is capable of receiving ERC721
* or else they may be permanently lost. Usage of {safeTransferFrom} prevents loss, though the caller must
* understand this adds an external call which potentially creates a reentrancy vulnerability.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
*
* Emits a {Transfer} event.
*/
function transferFrom(address from, address to, uint256 tokenId) external;
/**
* @dev Gives permission to `to` to transfer `tokenId` token to another account.
* The approval is cleared when the token is transferred.
*
* Only a single account can be approved at a time, so approving the zero address clears previous approvals.
*
* Requirements:
*
* - The caller must own the token or be an approved operator.
* - `tokenId` must exist.
*
* Emits an {Approval} event.
*/
function approve(address to, uint256 tokenId) external;
/**
* @dev Approve or remove `operator` as an operator for the caller.
* Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
*
* Requirements:
*
* - The `operator` cannot be the caller.
*
* Emits an {ApprovalForAll} event.
*/
function setApprovalForAll(address operator, bool approved) external;
/**
* @dev Returns the account approved for `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function getApproved(uint256 tokenId) external view returns (address operator);
/**
* @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
*
* See {setApprovalForAll}
*/
function isApprovedForAll(address owner, address operator) external view returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721Receiver.sol)
pragma solidity ^0.8.0;
/**
* @title ERC721 token receiver interface
* @dev Interface for any contract that wants to support safeTransfers
* from ERC721 asset contracts.
*/
interface IERC721Receiver {
/**
* @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
* by `operator` from `from`, this function is called.
*
* It must return its Solidity selector to confirm the token transfer.
* If any other value is returned or the interface is not implemented by the recipient, the transfer will be reverted.
*
* The selector can be obtained in Solidity with `IERC721Receiver.onERC721Received.selector`.
*/
function onERC721Received(
address operator,
address from,
uint256 tokenId,
bytes calldata data
) external returns (bytes4);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC721/utils/ERC721Holder.sol)
pragma solidity ^0.8.0;
import "../IERC721Receiver.sol";
/**
* @dev Implementation of the {IERC721Receiver} interface.
*
* Accepts all token transfers.
* Make sure the contract is able to use its token with {IERC721-safeTransferFrom}, {IERC721-approve} or {IERC721-setApprovalForAll}.
*/
contract ERC721Holder is IERC721Receiver {
/**
* @dev See {IERC721Receiver-onERC721Received}.
*
* Always returns `IERC721Receiver.onERC721Received.selector`.
*/
function onERC721Received(address, address, uint256, bytes memory) public virtual override returns (bytes4) {
return this.onERC721Received.selector;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)
pragma solidity ^0.8.1;
/**
* @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
*
* Furthermore, `isContract` will also return true if the target contract within
* the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
* which only has an effect at the end of a transaction.
* ====
*
* [IMPORTANT]
* ====
* You shouldn't rely on `isContract` to protect against flash loan attacks!
*
* Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
* like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
* constructor.
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize/address.code.length, which returns 0
// for contracts in construction, since the code is only stored at the end
// of the constructor execution.
return account.code.length > 0;
}
/**
* @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://consensys.net/diligence/blog/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/v0.8.0/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");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value,
string memory errorMessage
) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
(bool success, bytes memory returndata) = target.call{value: value}(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(
address target,
bytes memory data,
string memory errorMessage
) internal view returns (bytes memory) {
(bool success, bytes memory returndata) = target.staticcall(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
(bool success, bytes memory returndata) = target.delegatecall(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
* the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
*
* _Available since v4.8._
*/
function verifyCallResultFromTarget(
address target,
bool success,
bytes memory returndata,
string memory errorMessage
) internal view returns (bytes memory) {
if (success) {
if (returndata.length == 0) {
// only check isContract if the call was successful and the return data is empty
// otherwise we already know that it was a contract
require(isContract(target), "Address: call to non-contract");
}
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
/**
* @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason or using the provided one.
*
* _Available since v4.3._
*/
function verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) internal pure returns (bytes memory) {
if (success) {
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
function _revert(bytes memory returndata, string memory errorMessage) private pure {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
/// @solidity memory-safe-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
* @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 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) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/cryptography/ECDSA.sol)
pragma solidity ^0.8.0;
import "../Strings.sol";
/**
* @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
*
* These functions can be used to verify that a message was signed by the holder
* of the private keys of a given address.
*/
library ECDSA {
enum RecoverError {
NoError,
InvalidSignature,
InvalidSignatureLength,
InvalidSignatureS,
InvalidSignatureV // Deprecated in v4.8
}
function _throwError(RecoverError error) private pure {
if (error == RecoverError.NoError) {
return; // no error: do nothing
} else if (error == RecoverError.InvalidSignature) {
revert("ECDSA: invalid signature");
} else if (error == RecoverError.InvalidSignatureLength) {
revert("ECDSA: invalid signature length");
} else if (error == RecoverError.InvalidSignatureS) {
revert("ECDSA: invalid signature 's' value");
}
}
/**
* @dev Returns the address that signed a hashed message (`hash`) with
* `signature` or error string. This address can then be used for verification purposes.
*
* The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
* this function rejects them by requiring the `s` value to be in the lower
* half order, and the `v` value to be either 27 or 28.
*
* IMPORTANT: `hash` _must_ be the result of a hash operation for the
* verification to be secure: it is possible to craft signatures that
* recover to arbitrary addresses for non-hashed data. A safe way to ensure
* this is by receiving a hash of the original message (which may otherwise
* be too long), and then calling {toEthSignedMessageHash} on it.
*
* Documentation for signature generation:
* - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
* - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
*
* _Available since v4.3._
*/
function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
if (signature.length == 65) {
bytes32 r;
bytes32 s;
uint8 v;
// ecrecover takes the signature parameters, and the only way to get them
// currently is to use assembly.
/// @solidity memory-safe-assembly
assembly {
r := mload(add(signature, 0x20))
s := mload(add(signature, 0x40))
v := byte(0, mload(add(signature, 0x60)))
}
return tryRecover(hash, v, r, s);
} else {
return (address(0), RecoverError.InvalidSignatureLength);
}
}
/**
* @dev Returns the address that signed a hashed message (`hash`) with
* `signature`. This address can then be used for verification purposes.
*
* The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
* this function rejects them by requiring the `s` value to be in the lower
* half order, and the `v` value to be either 27 or 28.
*
* IMPORTANT: `hash` _must_ be the result of a hash operation for the
* verification to be secure: it is possible to craft signatures that
* recover to arbitrary addresses for non-hashed data. A safe way to ensure
* this is by receiving a hash of the original message (which may otherwise
* be too long), and then calling {toEthSignedMessageHash} on it.
*/
function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, signature);
_throwError(error);
return recovered;
}
/**
* @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
*
* See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
*
* _Available since v4.3._
*/
function tryRecover(bytes32 hash, bytes32 r, bytes32 vs) internal pure returns (address, RecoverError) {
bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
uint8 v = uint8((uint256(vs) >> 255) + 27);
return tryRecover(hash, v, r, s);
}
/**
* @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
*
* _Available since v4.2._
*/
function recover(bytes32 hash, bytes32 r, bytes32 vs) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, r, vs);
_throwError(error);
return recovered;
}
/**
* @dev Overload of {ECDSA-tryRecover} that receives the `v`,
* `r` and `s` signature fields separately.
*
* _Available since v4.3._
*/
function tryRecover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal pure returns (address, RecoverError) {
// EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
// unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
// the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
// signatures from current libraries generate a unique signature with an s-value in the lower half order.
//
// If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
// with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
// vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
// these malleable signatures as well.
if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
return (address(0), RecoverError.InvalidSignatureS);
}
// If the signature is valid (and not malleable), return the signer address
address signer = ecrecover(hash, v, r, s);
if (signer == address(0)) {
return (address(0), RecoverError.InvalidSignature);
}
return (signer, RecoverError.NoError);
}
/**
* @dev Overload of {ECDSA-recover} that receives the `v`,
* `r` and `s` signature fields separately.
*/
function recover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, v, r, s);
_throwError(error);
return recovered;
}
/**
* @dev Returns an Ethereum Signed Message, created from a `hash`. This
* produces hash corresponding to the one signed with the
* https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
* JSON-RPC method as part of EIP-191.
*
* See {recover}.
*/
function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32 message) {
// 32 is the length in bytes of hash,
// enforced by the type signature above
/// @solidity memory-safe-assembly
assembly {
mstore(0x00, "\x19Ethereum Signed Message:\n32")
mstore(0x1c, hash)
message := keccak256(0x00, 0x3c)
}
}
/**
* @dev Returns an Ethereum Signed Message, created from `s`. This
* produces hash corresponding to the one signed with the
* https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
* JSON-RPC method as part of EIP-191.
*
* See {recover}.
*/
function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n", Strings.toString(s.length), s));
}
/**
* @dev Returns an Ethereum Signed Typed Data, created from a
* `domainSeparator` and a `structHash`. This produces hash corresponding
* to the one signed with the
* https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
* JSON-RPC method as part of EIP-712.
*
* See {recover}.
*/
function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32 data) {
/// @solidity memory-safe-assembly
assembly {
let ptr := mload(0x40)
mstore(ptr, "\x19\x01")
mstore(add(ptr, 0x02), domainSeparator)
mstore(add(ptr, 0x22), structHash)
data := keccak256(ptr, 0x42)
}
}
/**
* @dev Returns an Ethereum Signed Data with intended validator, created from a
* `validator` and `data` according to the version 0 of EIP-191.
*
* See {recover}.
*/
function toDataWithIntendedValidatorHash(address validator, bytes memory data) internal pure returns (bytes32) {
return keccak256(abi.encodePacked("\x19\x00", validator, data));
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/cryptography/SignatureChecker.sol)
pragma solidity ^0.8.0;
import "./ECDSA.sol";
import "../../interfaces/IERC1271.sol";
/**
* @dev Signature verification helper that can be used instead of `ECDSA.recover` to seamlessly support both ECDSA
* signatures from externally owned accounts (EOAs) as well as ERC1271 signatures from smart contract wallets like
* Argent and Gnosis Safe.
*
* _Available since v4.1._
*/
library SignatureChecker {
/**
* @dev Checks if a signature is valid for a given signer and data hash. If the signer is a smart contract, the
* signature is validated against that smart contract using ERC1271, otherwise it's validated using `ECDSA.recover`.
*
* NOTE: Unlike ECDSA signatures, contract signatures are revocable, and the outcome of this function can thus
* change through time. It could return true at block N and false at block N+1 (or the opposite).
*/
function isValidSignatureNow(address signer, bytes32 hash, bytes memory signature) internal view returns (bool) {
(address recovered, ECDSA.RecoverError error) = ECDSA.tryRecover(hash, signature);
return
(error == ECDSA.RecoverError.NoError && recovered == signer) ||
isValidERC1271SignatureNow(signer, hash, signature);
}
/**
* @dev Checks if a signature is valid for a given signer and data hash. The signature is validated
* against the signer smart contract using ERC1271.
*
* NOTE: Unlike ECDSA signatures, contract signatures are revocable, and the outcome of this function can thus
* change through time. It could return true at block N and false at block N+1 (or the opposite).
*/
function isValidERC1271SignatureNow(
address signer,
bytes32 hash,
bytes memory signature
) internal view returns (bool) {
(bool success, bytes memory result) = signer.staticcall(
abi.encodeWithSelector(IERC1271.isValidSignature.selector, hash, signature)
);
return (success &&
result.length >= 32 &&
abi.decode(result, (bytes32)) == bytes32(IERC1271.isValidSignature.selector));
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
pragma solidity ^0.8.0;
import "./IERC165.sol";
/**
* @dev Implementation of the {IERC165} interface.
*
* Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
* for the additional interface id that will be supported. For example:
*
* ```solidity
* function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
* return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
* }
* ```
*
* Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
*/
abstract contract ERC165 is IERC165 {
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
return interfaceId == type(IERC165).interfaceId;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC165 standard, as defined in the
* https://eips.ethereum.org/EIPS/eip-165[EIP].
*
* Implementers can declare support of contract interfaces, which can then be
* queried by others ({ERC165Checker}).
*
* For an implementation, see {ERC165}.
*/
interface IERC165 {
/**
* @dev Returns true if this contract implements the interface defined by
* `interfaceId`. See the corresponding
* https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
* to learn more about how these ids are created.
*
* This function call must use less than 30 000 gas.
*/
function supportsInterface(bytes4 interfaceId) external view returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/math/Math.sol)
pragma solidity ^0.8.0;
/**
* @dev Standard math utilities missing in the Solidity language.
*/
library Math {
enum Rounding {
Down, // Toward negative infinity
Up, // Toward infinity
Zero // Toward zero
}
/**
* @dev Returns the largest of two numbers.
*/
function max(uint256 a, uint256 b) internal pure returns (uint256) {
return a > b ? a : b;
}
/**
* @dev Returns the smallest of two numbers.
*/
function min(uint256 a, uint256 b) internal pure returns (uint256) {
return a < b ? a : b;
}
/**
* @dev Returns the average of two numbers. The result is rounded towards
* zero.
*/
function average(uint256 a, uint256 b) internal pure returns (uint256) {
// (a + b) / 2 can overflow.
return (a & b) + (a ^ b) / 2;
}
/**
* @dev Returns the ceiling of the division of two numbers.
*
* This differs from standard division with `/` in that it rounds up instead
* of rounding down.
*/
function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
// (a + b - 1) / b can overflow on addition, so we distribute.
return a == 0 ? 0 : (a - 1) / b + 1;
}
/**
* @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
* @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
* with further edits by Uniswap Labs also under MIT license.
*/
function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 result) {
unchecked {
// 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
// use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
// variables such that product = prod1 * 2^256 + prod0.
uint256 prod0; // Least significant 256 bits of the product
uint256 prod1; // Most significant 256 bits of the product
assembly {
let mm := mulmod(x, y, not(0))
prod0 := mul(x, y)
prod1 := sub(sub(mm, prod0), lt(mm, prod0))
}
// Handle non-overflow cases, 256 by 256 division.
if (prod1 == 0) {
// Solidity will revert if denominator == 0, unlike the div opcode on its own.
// The surrounding unchecked block does not change this fact.
// See https://docs.soliditylang.org/en/latest/control-structures.html#checked-or-unchecked-arithmetic.
return prod0 / denominator;
}
// Make sure the result is less than 2^256. Also prevents denominator == 0.
require(denominator > prod1, "Math: mulDiv overflow");
///////////////////////////////////////////////
// 512 by 256 division.
///////////////////////////////////////////////
// Make division exact by subtracting the remainder from [prod1 prod0].
uint256 remainder;
assembly {
// Compute remainder using mulmod.
remainder := mulmod(x, y, denominator)
// Subtract 256 bit number from 512 bit number.
prod1 := sub(prod1, gt(remainder, prod0))
prod0 := sub(prod0, remainder)
}
// Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
// See https://cs.stackexchange.com/q/138556/92363.
// Does not overflow because the denominator cannot be zero at this stage in the function.
uint256 twos = denominator & (~denominator + 1);
assembly {
// Divide denominator by twos.
denominator := div(denominator, twos)
// Divide [prod1 prod0] by twos.
prod0 := div(prod0, twos)
// Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
twos := add(div(sub(0, twos), twos), 1)
}
// Shift in bits from prod1 into prod0.
prod0 |= prod1 * twos;
// Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
// that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
// four bits. That is, denominator * inv = 1 mod 2^4.
uint256 inverse = (3 * denominator) ^ 2;
// Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
// in modular arithmetic, doubling the correct bits in each step.
inverse *= 2 - denominator * inverse; // inverse mod 2^8
inverse *= 2 - denominator * inverse; // inverse mod 2^16
inverse *= 2 - denominator * inverse; // inverse mod 2^32
inverse *= 2 - denominator * inverse; // inverse mod 2^64
inverse *= 2 - denominator * inverse; // inverse mod 2^128
inverse *= 2 - denominator * inverse; // inverse mod 2^256
// Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
// This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
// less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
// is no longer required.
result = prod0 * inverse;
return result;
}
}
/**
* @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
*/
function mulDiv(uint256 x, uint256 y, uint256 denominator, Rounding rounding) internal pure returns (uint256) {
uint256 result = mulDiv(x, y, denominator);
if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
result += 1;
}
return result;
}
/**
* @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
*
* Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
*/
function sqrt(uint256 a) internal pure returns (uint256) {
if (a == 0) {
return 0;
}
// For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
//
// We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
// `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
//
// This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
// → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
// → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
//
// Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
uint256 result = 1 << (log2(a) >> 1);
// At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
// since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
// every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
// into the expected uint128 result.
unchecked {
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
return min(result, a / result);
}
}
/**
* @notice Calculates sqrt(a), following the selected rounding direction.
*/
function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
unchecked {
uint256 result = sqrt(a);
return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
}
}
/**
* @dev Return the log in base 2, rounded down, of a positive value.
* Returns 0 if given 0.
*/
function log2(uint256 value) internal pure returns (uint256) {
uint256 result = 0;
unchecked {
if (value >> 128 > 0) {
value >>= 128;
result += 128;
}
if (value >> 64 > 0) {
value >>= 64;
result += 64;
}
if (value >> 32 > 0) {
value >>= 32;
result += 32;
}
if (value >> 16 > 0) {
value >>= 16;
result += 16;
}
if (value >> 8 > 0) {
value >>= 8;
result += 8;
}
if (value >> 4 > 0) {
value >>= 4;
result += 4;
}
if (value >> 2 > 0) {
value >>= 2;
result += 2;
}
if (value >> 1 > 0) {
result += 1;
}
}
return result;
}
/**
* @dev Return the log in base 2, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/
function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
unchecked {
uint256 result = log2(value);
return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
}
}
/**
* @dev Return the log in base 10, rounded down, of a positive value.
* Returns 0 if given 0.
*/
function log10(uint256 value) internal pure returns (uint256) {
uint256 result = 0;
unchecked {
if (value >= 10 ** 64) {
value /= 10 ** 64;
result += 64;
}
if (value >= 10 ** 32) {
value /= 10 ** 32;
result += 32;
}
if (value >= 10 ** 16) {
value /= 10 ** 16;
result += 16;
}
if (value >= 10 ** 8) {
value /= 10 ** 8;
result += 8;
}
if (value >= 10 ** 4) {
value /= 10 ** 4;
result += 4;
}
if (value >= 10 ** 2) {
value /= 10 ** 2;
result += 2;
}
if (value >= 10 ** 1) {
result += 1;
}
}
return result;
}
/**
* @dev Return the log in base 10, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/
function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
unchecked {
uint256 result = log10(value);
return result + (rounding == Rounding.Up && 10 ** result < value ? 1 : 0);
}
}
/**
* @dev Return the log in base 256, rounded down, of a positive value.
* Returns 0 if given 0.
*
* Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
*/
function log256(uint256 value) internal pure returns (uint256) {
uint256 result = 0;
unchecked {
if (value >> 128 > 0) {
value >>= 128;
result += 16;
}
if (value >> 64 > 0) {
value >>= 64;
result += 8;
}
if (value >> 32 > 0) {
value >>= 32;
result += 4;
}
if (value >> 16 > 0) {
value >>= 16;
result += 2;
}
if (value >> 8 > 0) {
result += 1;
}
}
return result;
}
/**
* @dev Return the log in base 256, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/
function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
unchecked {
uint256 result = log256(value);
return result + (rounding == Rounding.Up && 1 << (result << 3) < value ? 1 : 0);
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/math/SignedMath.sol)
pragma solidity ^0.8.0;
/**
* @dev Standard signed math utilities missing in the Solidity language.
*/
library SignedMath {
/**
* @dev Returns the largest of two signed numbers.
*/
function max(int256 a, int256 b) internal pure returns (int256) {
return a > b ? a : b;
}
/**
* @dev Returns the smallest of two signed numbers.
*/
function min(int256 a, int256 b) internal pure returns (int256) {
return a < b ? a : b;
}
/**
* @dev Returns the average of two signed numbers without overflow.
* The result is rounded towards zero.
*/
function average(int256 a, int256 b) internal pure returns (int256) {
// Formula from the book "Hacker's Delight"
int256 x = (a & b) + ((a ^ b) >> 1);
return x + (int256(uint256(x) >> 255) & (a ^ b));
}
/**
* @dev Returns the absolute unsigned value of a signed value.
*/
function abs(int256 n) internal pure returns (uint256) {
unchecked {
// must be unchecked in order to support `n = type(int256).min`
return uint256(n >= 0 ? n : -n);
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Strings.sol)
pragma solidity ^0.8.0;
import "./math/Math.sol";
import "./math/SignedMath.sol";
/**
* @dev String operations.
*/
library Strings {
bytes16 private constant _SYMBOLS = "0123456789abcdef";
uint8 private constant _ADDRESS_LENGTH = 20;
/**
* @dev Converts a `uint256` to its ASCII `string` decimal representation.
*/
function toString(uint256 value) internal pure returns (string memory) {
unchecked {
uint256 length = Math.log10(value) + 1;
string memory buffer = new string(length);
uint256 ptr;
/// @solidity memory-safe-assembly
assembly {
ptr := add(buffer, add(32, length))
}
while (true) {
ptr--;
/// @solidity memory-safe-assembly
assembly {
mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
}
value /= 10;
if (value == 0) break;
}
return buffer;
}
}
/**
* @dev Converts a `int256` to its ASCII `string` decimal representation.
*/
function toString(int256 value) internal pure returns (string memory) {
return string(abi.encodePacked(value < 0 ? "-" : "", toString(SignedMath.abs(value))));
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
*/
function toHexString(uint256 value) internal pure returns (string memory) {
unchecked {
return toHexString(value, Math.log256(value) + 1);
}
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
*/
function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
bytes memory buffer = new bytes(2 * length + 2);
buffer[0] = "0";
buffer[1] = "x";
for (uint256 i = 2 * length + 1; i > 1; --i) {
buffer[i] = _SYMBOLS[value & 0xf];
value >>= 4;
}
require(value == 0, "Strings: hex length insufficient");
return string(buffer);
}
/**
* @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
*/
function toHexString(address addr) internal pure returns (string memory) {
return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
}
/**
* @dev Returns true if the two strings are equal.
*/
function equal(string memory a, string memory b) internal pure returns (bool) {
return keccak256(bytes(a)) == keccak256(bytes(b));
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {Ownable} from "../utils/Ownable.sol";
import {INftWrapper} from "../interfaces/INftWrapper.sol";
import {IEscrow} from "../interfaces/IEscrow.sol";
import {NftReceiver} from "../utils/NftReceiver.sol";
import {INftfiHub} from "../interfaces/INftfiHub.sol";
import {ContractKeys} from "../utils/ContractKeys.sol";
import {LoanCoordinator} from "../loans/LoanCoordinator.sol";
import {IPermittedNFTs} from "../interfaces/IPermittedNFTs.sol";
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import {Address} from "@openzeppelin/contracts/utils/Address.sol";
import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
/**
* @title Escrow
* @author NFTfi
* @notice Protocol wide escrow contract for NFT collateral
* used when a user doen't have a personal escrow deployed
**/
contract Escrow is IEscrow, Ownable, NftReceiver {
using SafeERC20 for IERC20;
// collateral contract => collateral id => locker contract(loan) => amount (preparing for 1155)
mapping(address => mapping(uint256 => mapping(address => uint256))) internal _tokensLockedByLoan;
/**
* @dev keeps track of tokens being held as loan collateral, so we dont allow these
* to be transferred with the aridrop draining functions
* nft contract address => nft id => amount (in case of 1155)
*/
mapping(address => mapping(uint256 => uint256)) internal _escrowTokens;
// addresses of contracts thathas plugin rights
mapping(address => bool) private plugins;
// solhint-disable-next-line immutable-vars-naming
INftfiHub public immutable hub;
event Locked(
address indexed nftCollateralContract,
uint256 indexed nftCollateralId,
address indexed borrower,
address loanContract
);
event Unlocked(
address indexed nftCollateralContract,
uint256 indexed nftCollateralId,
address indexed recipient,
address loanContract
);
event LoanHandedOver(
address indexed nftCollateralContract,
uint256 indexed nftCollateralId,
address oldLoanContract,
address newloanContract
);
error OnlyLoanContract();
error CollateralNotLockedByLoan();
error NoSuchTokenOwned();
error NoSuchERC1155sOwned();
error NoSuchERC721Owned();
error NoSuchERC20Owned();
error TokenIsCollateral();
error CollateralDelegated();
error NotAPlugin();
/**
* @notice Sets the admin of the contract.
*
* @param _admin - Initial admin of this contract.
*/
constructor(address _admin, address _hub) Ownable(_admin) {
hub = INftfiHub(_hub);
}
/**
* @notice Checks if the caller is is a loan contract
*/
modifier onlyLoan() {
// checking that locker is a registered loan type
// WARNING if we ever register an external account (or malicious contract) as a loan type that
// account can steal user nfts that has been approved for this contract by locking and unlocking
if (
LoanCoordinator(hub.getContract(ContractKeys.LOAN_COORDINATOR)).getTypeOfLoanContract(msg.sender) ==
bytes32(0)
) revert OnlyLoanContract();
_;
}
/**
* @notice Checks if the caller is the locker of the given collateral nft in the parameter
*
* @param _nftCollateralContract - Address of the NFT collateral contract.
* @param _nftCollateralId - ID of the NFT collateral.
*/
modifier onlyLockingLoan(address _nftCollateralContract, uint256 _nftCollateralId) {
if (_tokensLockedByLoan[_nftCollateralContract][_nftCollateralId][msg.sender] == 0)
revert CollateralNotLockedByLoan();
_;
}
/**
* @notice Locks collateral NFT for a loan.
*
* @param _nftCollateralWrapper - Address of the NFT wrapper contract.
* @param _nftCollateralContract - Address of the NFT collateral contract.
* @param _nftCollateralId - ID of the NFT collateral.
* @param _borrower - Address of the borrower.
*/
function lockCollateral(
address _nftCollateralWrapper,
address _nftCollateralContract,
uint256 _nftCollateralId,
address _borrower
) external virtual override onlyLoan {
_lockCollateral(_nftCollateralContract, _nftCollateralId);
_transferNFT(_nftCollateralWrapper, _nftCollateralContract, _nftCollateralId, _borrower, address(this));
emit Locked(_nftCollateralContract, _nftCollateralId, _borrower, msg.sender);
}
/**
* @notice Internal function to lock collateral.
*
* @param _nftCollateralContract - Address of the NFT collateral contract.
* @param _nftCollateralId - ID of the NFT collateral.
*/
function _lockCollateral(address _nftCollateralContract, uint256 _nftCollateralId) internal {
_tokensLockedByLoan[_nftCollateralContract][_nftCollateralId][msg.sender] += 1;
_escrowTokens[_nftCollateralContract][_nftCollateralId] += 1;
}
/**
* @notice Unlocks collateral NFT for a loan.
*
* @param _nftCollateralWrapper - Address of the NFT wrapper contract.
* @param _nftCollateralContract - Address of the NFT collateral contract.
* @param _nftCollateralId - ID of the NFT collateral.
* @param _recipient - Address of the recipient.
*/
function unlockCollateral(
address _nftCollateralWrapper,
address _nftCollateralContract,
uint256 _nftCollateralId,
address _recipient
) external virtual override onlyLockingLoan(_nftCollateralContract, _nftCollateralId) {
_unlockCollateral(_nftCollateralContract, _nftCollateralId);
_transferNFT(_nftCollateralWrapper, _nftCollateralContract, _nftCollateralId, address(this), _recipient);
emit Unlocked(_nftCollateralContract, _nftCollateralId, _recipient, msg.sender);
}
/**
* @notice Internal function to unlock collateral.
*
* @param _nftCollateralContract - Address of the NFT collateral contract.
* @param _nftCollateralId - ID of the NFT collateral.
*/
function _unlockCollateral(address _nftCollateralContract, uint256 _nftCollateralId) internal {
_tokensLockedByLoan[_nftCollateralContract][_nftCollateralId][msg.sender] -= 1;
_escrowTokens[_nftCollateralContract][_nftCollateralId] -= 1;
}
function handOverLoan(
address _newLoanContract,
address _nftCollateralContract,
uint256 _nftCollateralId
) external virtual override onlyLockingLoan(_nftCollateralContract, _nftCollateralId) {
_tokensLockedByLoan[_nftCollateralContract][_nftCollateralId][msg.sender] -= 1;
_tokensLockedByLoan[_nftCollateralContract][_nftCollateralId][_newLoanContract] += 1;
emit LoanHandedOver(_nftCollateralContract, _nftCollateralId, msg.sender, _newLoanContract);
}
/**
* @notice Checks if a collateral NFT is in escrow with a specific loan.
*
@param _nftCollateralContract - Address of the NFT collateral contract.
* @param _nftCollateralId - ID of the NFT collateral.
* @param _loan - Address of the loan contract.
* @return bool - True if the NFT is in escrow with the loan, false otherwise.
*/
function isInEscrowWithLoan(
address _nftCollateralContract,
uint256 _nftCollateralId,
address _loan
) external view override returns (bool) {
return _tokensLockedByLoan[_nftCollateralContract][_nftCollateralId][_loan] > 0;
}
/**
* @dev Transfers several types of NFTs using a wrapper that knows how to handle each case.
*
* @param _sender - Current owner of the NF
* @param _recipient - Recipient of the transfer
*/
function _transferNFT(
address _nftCollateralWrapper,
address _nftCollateralContract,
uint256 _nftCollateralId,
address _sender,
address _recipient
) internal {
Address.functionDelegateCall(
_nftCollateralWrapper,
abi.encodeWithSelector(
INftWrapper(_nftCollateralWrapper).transferNFT.selector,
_sender,
_recipient,
_nftCollateralContract,
_nftCollateralId
),
"NFT not successfully transferred"
);
}
/**
* @dev Checks if the contract owns a specific NFT.
*
* @param _nftCollateralWrapper - Address of the NFT wrapper contract.
* @param _nftCollateralContract - Address of the NFT collateral contract.
* @param _nftCollateralId - ID of the NFT collateral.
* @return bool - True if the contract owns the NFT, false otherwise.
*/
function _isOwned(
address _nftCollateralWrapper,
address _nftCollateralContract,
uint256 _nftCollateralId
) internal returns (bool) {
bytes memory result = Address.functionDelegateCall(
_nftCollateralWrapper,
abi.encodeWithSelector(
INftWrapper(_nftCollateralWrapper).isOwner.selector,
address(this),
_nftCollateralContract,
_nftCollateralId
),
"Ownership check failed"
);
return abi.decode(result, (bool));
}
/**
* @notice used by the owner account to be able to drain sturck ERC20 tokens for revenue share
* for the locked collateral NFT-s
* @param _tokenAddress - address of the token contract for the token to be sent out
* @param _receiver - receiver of the token
*/
function drainERC20Airdrop(address _tokenAddress, uint256 amount, address _receiver) external onlyOwner {
// ensuring that this cannot be used to transfer any permitted, escrowed nft
// that has the following transfer function (interpreting amount as id):
// function transfer(address _to, uint256 _tokenId), like CryptoKitties for example
if (_escrowTokens[_tokenAddress][amount] > 0) {
revert TokenIsCollateral();
}
IERC20 tokenContract = IERC20(_tokenAddress);
uint256 balance = tokenContract.balanceOf(address(this));
if (balance == 0) {
revert NoSuchERC20Owned();
}
tokenContract.safeTransfer(_receiver, amount);
}
/**
* @notice used by the owner account to be able to drain any tokens used as collateral that is not locked in a loan
* @param _tokenAddress - address of the token contract for the token to be sent out
* @param _tokenId - id token to be sent out
* @param _receiver - receiver of the token
*/
function withdrawNFT(address _tokenAddress, uint256 _tokenId, address _receiver) external onlyOwner {
if (_escrowTokens[_tokenAddress][_tokenId] > 0) {
revert TokenIsCollateral();
}
address tokenWrapper = IPermittedNFTs(hub.getContract(ContractKeys.PERMITTED_NFTS)).getNFTWrapper(
_tokenAddress
);
if (!_isOwned(tokenWrapper, _tokenAddress, _tokenId)) {
revert NoSuchTokenOwned();
}
_transferNFT(tokenWrapper, _tokenAddress, _tokenId, address(this), _receiver);
}
/**
* @notice used by the owner account to be able to drain stuck or airdropped NFTs
* a check prevents draining collateral
* @param _nftType - nft type key which is sourced from nftfi hub
* @param _tokenAddress - address of the token contract for the token to be sent out
* @param _tokenId - id token to be sent out
* @param _receiver - receiver of the token
*/
function drainNFT(
string memory _nftType,
address _tokenAddress,
uint256 _tokenId,
address _receiver
) external onlyOwner {
if (_escrowTokens[_tokenAddress][_tokenId] > 0) {
revert TokenIsCollateral();
}
bytes32 nftTypeKey = _getIdFromStringKey(_nftType);
address transferWrapper = IPermittedNFTs(hub.getContract(ContractKeys.PERMITTED_NFTS)).getNftTypeWrapper(
nftTypeKey
);
_transferNFT(transferWrapper, _tokenAddress, _tokenId, address(this), _receiver);
}
/**
* @notice Admin function for adding a plugin that can make an arbitrary function call
* WARNING! serious security implications! plugins can move the collateral
* @param _plugin address of the plugin
*/
function addPlugin(address _plugin) external virtual onlyOwner {
plugins[_plugin] = true;
}
/**
* @notice Admin function for removing a plugin that can make an arbitrary function call
* @param _plugin address of the plugin
*/
function removePlugin(address _plugin) external virtual onlyOwner {
plugins[_plugin] = false;
}
function pluginCall(address _target, bytes memory _data) external returns (bool, bytes memory) {
if (!plugins[msg.sender]) revert NotAPlugin();
// solhint-disable-next-line avoid-low-level-calls
return _target.call(_data);
}
/**
* @notice Returns the bytes32 representation of a string (copied from ContractKeys so we dont need it as a lib)
* @param _key the string key
* @return id bytes32 representation
*/
function _getIdFromStringKey(string memory _key) internal pure returns (bytes32 id) {
// solhint-disable-next-line custom-errors
require(bytes(_key).length <= 32, "invalid key");
// solhint-disable-next-line no-inline-assembly
assembly {
id := mload(add(_key, 32))
}
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {Escrow} from "./Escrow.sol";
import {IPersonalEscrow} from "../interfaces/IPersonalEscrow.sol";
import {IEscrow} from "../interfaces/IEscrow.sol";
import {INftWrapper} from "../interfaces/INftWrapper.sol";
import {Initializable} from "@openzeppelin/contracts/proxy/utils/Initializable.sol";
import {Address} from "@openzeppelin/contracts/utils/Address.sol";
/**
* @title PersonalEscrow
* @author NFTfi
* @notice User-specific escrow contract
**/
contract PersonalEscrow is IPersonalEscrow, Escrow, Initializable {
event Initialized(address owner);
/**
* @dev Initializes the Escrow contract with a null owner.
* @param _hub Address of the NftfiHub contract
*/
constructor(address _hub) Escrow(address(0), _hub) {}
/**
* @notice Initializes the contract setting the owner.
* @param _owner Address of the new owner of the excrow
*/
function initialize(address _owner) external initializer {
_setOwner(_owner);
emit Initialized(_owner);
}
/**
* @notice Locks the NFT collateral in the escrow.
* @param _nftCollateralWrapper Address of the NFT collateral wrapper
* @param _nftCollateralContract Address of the NFT collateral contract
* @param _nftCollateralId ID of the NFT collateral
* @param _borrower Address of the borrower
*/
function lockCollateral(
address _nftCollateralWrapper,
address _nftCollateralContract,
uint256 _nftCollateralId,
address _borrower
) external override(IEscrow, Escrow) onlyLoan {
// we need to check that the escrow owns more collateral tokens that the ones already locked
// - in case of balance 0 check is FALSE: we have to attempt to transfer the token
// - in case of non fungibles if balance is 1 and escrowed is 0, check is TRUE we have the unlocked token: OK
// - in case of non fungibles if balance is 1 and escrowed is 1,
// we have the token already locked, check is FALSE - transfer will be attempted and fail
// (because it's unique ans is already here)
// - in case of fungibles (1155) if balance is n + k (k>1 positive integer) and escrowed is n,
// check is TRUE, we have unlocked token(s): OK
// - in case of fungibles (1155) if balance is n and escrowed is n (equal),
// we only have locked token(s), check is FALSE: we have to attempt to transfer the token
if (
_balanceOf(_nftCollateralWrapper, _nftCollateralContract, _nftCollateralId) >
_escrowTokens[_nftCollateralContract][_nftCollateralId]
) {
// we only lock, collateral is already in contract, no need to transfer
_lockCollateral(_nftCollateralContract, _nftCollateralId);
} else {
// we lock and transfer
_lockCollateral(_nftCollateralContract, _nftCollateralId);
_transferNFT(_nftCollateralWrapper, _nftCollateralContract, _nftCollateralId, _borrower, address(this));
}
}
/**
* @dev Checks balance of a specific NFT owned by the contract.
*
* @param _nftCollateralWrapper - Address of the NFT wrapper contract.
* @param _nftCollateralContract - Address of the NFT collateral contract.
* @param _nftCollateralId - ID of the NFT collateral.
* @return bool - True if the contract owns the NFT, false otherwise.
*/
function _balanceOf(
address _nftCollateralWrapper,
address _nftCollateralContract,
uint256 _nftCollateralId
) internal returns (uint256) {
bytes memory result = Address.functionDelegateCall(
_nftCollateralWrapper,
abi.encodeWithSelector(
INftWrapper(_nftCollateralWrapper).balanceOf.selector,
address(this),
_nftCollateralContract,
_nftCollateralId
),
"Balance check failed"
);
return abi.decode(result, (uint256));
}
/**
* @notice Unlocks the NFT collateral from the escrow and transfers it to the recipient.
* @param _nftCollateralWrapper Address of the NFT collateral wrapper
* @param _nftCollateralContract Address of the NFT collateral contract
* @param _nftCollateralId ID of the NFT collateral
* @param _recipient Address of the recipient
*/
function unlockCollateral(
address _nftCollateralWrapper,
address _nftCollateralContract,
uint256 _nftCollateralId,
address _recipient
) external override(IEscrow, Escrow) onlyLockingLoan(_nftCollateralContract, _nftCollateralId) {
_unlockCollateral(_nftCollateralContract, _nftCollateralId);
_transferNFT(_nftCollateralWrapper, _nftCollateralContract, _nftCollateralId, address(this), _recipient);
}
/**
* @notice unlocks and approves for an escrow contract that is taking over, only locking loan can initiate
* @param _nftCollateralWrapper Address of the NFT collateral wrapper
* @param _nftCollateralContract Address of the NFT collateral contract
* @param _nftCollateralId ID of the NFT collateral
* @param _recipientEscrow Address of the recipient escrow contract
*/
function handOverCollateralToEscrow(
address _nftCollateralWrapper,
address _nftCollateralContract,
uint256 _nftCollateralId,
address _recipientEscrow
) external override onlyLockingLoan(_nftCollateralContract, _nftCollateralId) {
_unlockCollateral(_nftCollateralContract, _nftCollateralId);
_approveNFT(_nftCollateralWrapper, _recipientEscrow, _nftCollateralContract, _nftCollateralId);
}
/**
* @notice Unlocks the NFT collateral from the escrow without transferring it.
* @param _nftCollateralContract Address of the NFT collateral contract
* @param _nftCollateralId ID of the NFT collateral
*/
function unlockAndKeepCollateral(
address _nftCollateralContract,
uint256 _nftCollateralId
) external onlyLockingLoan(_nftCollateralContract, _nftCollateralId) {
_unlockCollateral(_nftCollateralContract, _nftCollateralId);
}
/**
* @dev Approves an NFT to be used by another address trough the NFT adaptor.
*
* @param _to - The address to approve to transfer or manage the NFT.
* @param _nftCollateralContract - The contract address of the NFT.
* @param _nftCollateralId - The token ID of the NFT.
*
* @return bool - Returns true if the approval was successful.
*/
function _approveNFT(
address _nftCollateralWrapper,
address _to,
address _nftCollateralContract,
uint256 _nftCollateralId
) internal returns (bool) {
bytes memory result = Address.functionDelegateCall(
_nftCollateralWrapper,
abi.encodeWithSelector(
INftWrapper(_nftCollateralWrapper).approveNFT.selector,
_to,
_nftCollateralContract,
_nftCollateralId
),
"NFT not successfully approved"
);
return abi.decode(result, (bool));
}
function addPlugin(address) external pure override(Escrow) {
revert AddingOrRemovingPluginsNotAllowed();
}
function removePlugin(address) external pure override(Escrow) {
revert AddingOrRemovingPluginsNotAllowed();
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {Clones} from "@openzeppelin/contracts/proxy/Clones.sol";
import {Pausable} from "@openzeppelin/contracts/security/Pausable.sol";
import {Ownable} from "../utils/Ownable.sol";
import {PersonalEscrow} from "./PersonalEscrow.sol";
import {IPersonalEscrowFactory} from "../interfaces/IPersonalEscrowFactory.sol";
/**
* @title PersonalEscrowFactory
* @author NFTfi
* @notice Used to deploy new personal escrow contracts for specific users
*/
contract PersonalEscrowFactory is IPersonalEscrowFactory, Ownable, Pausable {
// solhint-disable-next-line immutable-vars-naming
address public immutable personalEscrowImplementation;
string public baseURI;
// Incremental token id
uint256 public tokenCount = 0;
mapping(address owner => address escrow) private _personalEscrowOfOwner;
mapping(address => bool) private _isPersonalEscrow;
event PersonalEscrowCreated(address indexed instance, address indexed owner, address creator);
error PersonalEscrowAlreadyExistsForUser();
/**
* @param _personalEscrowImplementation - deployed master copy of the personal escrow contract
*/
constructor(address _personalEscrowImplementation, address _admin) Ownable(_admin) {
personalEscrowImplementation = _personalEscrowImplementation;
_pause();
}
/**
* @dev Triggers stopped state.
*
* Requirements:
*
* - Only the owner can call this method.
* - The contract must not be paused.
*/
function pause() external onlyOwner {
_pause();
}
/**
* @dev Returns to normal state.
*
* Requirements:
*
* - Only the owner can call this method.
* - The contract must be paused.
*/
function unpause() external onlyOwner {
_unpause();
}
/**
* @dev clones a new personal escrow contract
*/
function createPersonalEscrow() external whenNotPaused returns (address) {
if (_personalEscrowOfOwner[msg.sender] != address(0)) revert PersonalEscrowAlreadyExistsForUser();
address instance = Clones.clone(personalEscrowImplementation);
_personalEscrowOfOwner[msg.sender] = instance;
_isPersonalEscrow[instance] = true;
PersonalEscrow(instance).initialize(msg.sender);
emit PersonalEscrowCreated(instance, msg.sender, msg.sender);
return instance;
}
/**
* @dev retunrs escrow address of the owner
* @return address of the personal escrow
*/
function personalEscrowOfOwner(address _owner) external view returns (address) {
return _personalEscrowOfOwner[_owner];
}
/**
* @dev checks if the address is a personal escrow
* @return bool true if the address is a personal escrow
*/
function isPersonalEscrow(address _escrow) external view returns (bool) {
return _isPersonalEscrow[_escrow];
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
interface IDelegateCashPlugin {
struct DelegationSettings {
address to;
bytes32 rights;
bool isERC721;
}
function delegateERC721(
uint32 loanId,
string memory offerType,
address to,
address collateralContract,
uint256 tokenId,
bytes32 rights
) external;
function isCollateralDelegated(uint32 _loanId) external view returns (bool);
function getDelegationSettings(uint32 _loanId) external view returns (DelegationSettings memory);
function undelegateERC721(uint32 _loanId) external;
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
interface IERC20TransferManager {
function transfer(address _token, address _sender, address _recipient, uint256 _amount) external;
function safeLoanPaybackTransfer(address _token, address _sender, address _recipient, uint256 _amount) external;
function safeAdminFeeTransfer(address _token, address _sender, address _recipient, uint256 _amount) external;
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
interface IEscrow {
function lockCollateral(
address _nftCollateralWrapper,
address _nftCollateralContract,
uint256 _nftCollateralId,
address _borrower
) external;
function unlockCollateral(
address _nftCollateralWrapper,
address _nftCollateralContract,
uint256 _nftCollateralId,
address _recipient
) external;
function handOverLoan(address _newLoanContract, address _nftCollateralContract, uint256 _nftCollateralId) external;
function isInEscrowWithLoan(
address _nftCollateralContract,
uint256 _nftCollateralId,
address _loan
) external view returns (bool);
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
/**
* @title ILoanCoordinator
* @author NFTfi
* @dev LoanCoordinator interface.
*/
interface ILoanCoordinator {
enum StatusType {
NOT_EXISTS,
NEW,
REPAID,
LIQUIDATED
}
/**
* @notice This struct contains data related to a loan
*
* @param smartNftId - The id of both the promissory note and obligation receipt.
* @param status - The status in which the loan currently is.
* @param loanContract - Address of the contract that created the loan.
*/
struct Loan {
address loanContract;
uint64 smartNftId;
StatusType status;
}
function registerLoan() external returns (uint32);
function resetSmartNfts(uint32 _loanId) external;
function mintObligationReceipt(uint32 _loanId, address _borrower) external;
function mintPromissoryNote(uint32 _loanId, address _lender) external;
function resolveLoan(uint32 _loanId, bool liquidated) external;
function promissoryNoteToken() external view returns (address);
function obligationReceiptToken() external view returns (address);
function getLoanData(uint32 _loanId) external view returns (Loan memory);
function isValidLoanId(uint32 _loanId, address _loanContract) external view returns (bool);
function getDefaultLoanContractForOfferType(bytes32 _offerType) external view returns (address);
function getTypeOfLoanContract(address _loanContract) external view returns (bytes32);
function checkNonce(address _user, uint256 _nonce) external view;
function checkAndInvalidateNonce(address _user, uint256 _nonce) external;
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
/**
* @title INftfiHub
* @author NFTfi
* @dev NftfiHub interface
*/
interface INftfiHub {
function setContract(string calldata _contractKey, address _contractAddress) external;
function getContract(bytes32 _contractKey) external view returns (address);
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
/**
* @title INftWrapper
* @author NFTfi
* @dev Interface for NFT Wrappers.
*/
interface INftWrapper {
function transferNFT(address from, address to, address nftContract, uint256 tokenId) external returns (bool);
function approveNFT(address to, address nftContract, uint256 tokenId) external returns (bool);
function isOwner(address owner, address nftContract, uint256 tokenId) external view returns (bool);
function balanceOf(address owner, address nftContract, uint256 tokenId) external view returns (uint256);
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
interface IPermittedERC20s {
function getERC20Permit(address _erc20) external view returns (bool);
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
interface IPermittedNFTs {
function setNFTPermit(address _nftContract, string memory _nftType) external;
function getNFTPermit(address _nftContract) external view returns (bytes32);
function getNFTWrapper(address _nftContract) external view returns (address);
function getNftTypeWrapper(bytes32 _nftType) external view returns (address);
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {IEscrow} from "./IEscrow.sol";
interface IPersonalEscrow is IEscrow {
error AddingOrRemovingPluginsNotAllowed();
function handOverCollateralToEscrow(
address _nftCollateralWrapper,
address _nftCollateralContract,
uint256 _nftCollateralId,
address _recipientEscrow
) external;
function unlockAndKeepCollateral(address _nftCollateralContract, uint256 _nftCollateralId) external;
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
interface IPersonalEscrowFactory {
function pause() external;
function unpause() external;
function createPersonalEscrow() external returns (address);
function personalEscrowOfOwner(address _owner) external view returns (address);
function isPersonalEscrow(address _escrow) external view returns (bool);
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {Ownable} from "../utils/Ownable.sol";
import {Pausable} from "@openzeppelin/contracts/security/Pausable.sol";
import {ReentrancyGuard} from "@openzeppelin/contracts/security/ReentrancyGuard.sol";
/**
* @title BaseLoan
* @author NFTfi
* @dev Implements base functionalities common to all Loan types.
* Mostly related to governance and security.
*/
abstract contract BaseLoan is Ownable, Pausable, ReentrancyGuard {
/* *********** */
/* CONSTRUCTOR */
/* *********** */
/**
* @notice Sets the admin of the contract.
*
* @param _admin - Initial admin of this contract.
*/
constructor(address _admin) Ownable(_admin) {
// solhint-disable-previous-line no-empty-blocks
}
/* ********* */
/* FUNCTIONS */
/* ********* */
/**
* @dev Triggers stopped state.
*
* Requirements:
*
* - Only the owner can call this method.
* - The contract must not be paused.
*/
function pause() external onlyOwner {
_pause();
}
/**
* @dev Returns to normal state.
*
* Requirements:
*
* - Only the owner can call this method.
* - The contract must be paused.
*/
function unpause() external onlyOwner {
_unpause();
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {SmartNft} from "../smartNft/SmartNft.sol";
import {ILoanCoordinator} from "../interfaces/ILoanCoordinator.sol";
import {INftfiHub} from "../interfaces/INftfiHub.sol";
import {Ownable} from "../utils/Ownable.sol";
import {ContractKeyUtils} from "../utils/ContractKeyUtils.sol";
/**
* @title LoanCoordinator
* @author NFTfi
* @notice This contract is in charge of coordinating the creation, distribution and desctruction of the SmartNfts
* related to a loan, the Promossory Note and Obligaiton Receipt.
*/
contract LoanCoordinator is ILoanCoordinator, Ownable {
/* ******* */
/* STORAGE */
/* ******* */
// solhint-disable-next-line immutable-vars-naming
INftfiHub public immutable hub;
/**
* @dev For each loan type, records the address of the contract that implements the type
*/
mapping(bytes32 loanType => address offerAddress) private _defaultLoanContractForOfferType;
/**
* @dev reverse mapping of offerTypes - for each contract address, records the associated loan type
*/
mapping(address offerAddress => bytes32 loanType) private _typeOfLoanContract;
mapping(address => bool) private _isLoanContractDisabled;
/**
* @notice A continuously increasing counter that simultaneously allows every loan to have a unique ID and provides
* a running count of how many loans have been started by this contract.
*/
uint32 public totalNumLoans = 0;
uint32 public smartNftIdCounter = 0;
// The address that deployed this contract
// solhint-disable-next-line immutable-vars-naming
address private immutable _deployer;
bool private _initialized = false;
mapping(uint32 => Loan) private loans;
address public override promissoryNoteToken;
address public override obligationReceiptToken;
/**
* @notice A mapping that takes both a user's address and a loan nonce that was first used when signing an off-chain
* order and checks whether that nonce has previously either been used for a loan, or has been pre-emptively
* cancelled. The nonce referred to here is not the same as an Ethereum account's nonce. We are referring instead to
* nonces that are used by both the lender and the borrower when they are first signing off-chain NFTfi orders.
*
* These nonces can be any uint256 value that the user has not previously used to sign an off-chain order. Each
* nonce can be used at most once per user within NFTfi, regardless of whether they are the lender or the borrower
* in that situation. This serves two purposes. First, it prevents replay attacks where an attacker would submit a
* user's off-chain order more than once. Second, it allows a user to cancel an off-chain order by calling
* NFTfi.cancelLoanCommitment(), which marks the nonce as used and prevents any future loan from
* using the user's off-chain order that contains that nonce.
*/
mapping(bytes32 offerType => mapping(address user => mapping(uint256 nonce => bool nonceHasBeenUsed)))
internal _nonceHasBeenUsedForUserByOfferType;
/* ****** */
/* EVENTS */
/* ****** */
event UpdateStatus(uint32 indexed loanId, address indexed loanContract, StatusType newStatus);
/**
* @notice This event is fired whenever the admins register a loan type.
*
* @param offerType - offer type represented by keccak256('offer type').
* @param loanContract - Address of the loan type contract.
*/
event TypeUpdated(bytes32 indexed offerType, address indexed loanContract);
/* ************* */
/* CUSTOM ERRORS */
/* ************* */
error NotInitialized();
error OnlyDeployer();
error AlreadyInitialized();
error ObligationReceiptZeroAddress();
error PromissoryNoteZeroAddress();
error ObligationReceiptAlreadyExists();
error PromissoryNoteAlreadyExists();
error NotRegisteredLoanContract();
error DisabledLoanContract();
error PromissoryNoteDoesntExist();
error LoanStatusMustBeNEW();
error CallerNotLoanCreatorContract();
error OfferTypeIsEmpty();
error LoanContractAlreadyRegistered();
error FunctionInformationArityMismatch();
error InvalidNonce();
/**
* @dev Function using this modifier can only be executed after this contract is initialized
*
*/
modifier onlyInitialized() {
if (!_initialized) revert NotInitialized();
_;
}
/* *********** */
/* CONSTRUCTOR */
/* *********** */
/**
* @notice Sets the admin of the contract.
* Initializes `contractTypes` with a batch of loan types. Sets `NftfiHub`.
*
* @param _nftfiHub - Address of the NftfiHub contract
* @param _admin - Initial admin of this contract.
* @param _offerTypes - offer types represented by keccak256('offer type').
* @param _loanContracts - The addresses of each wrapper contract that implements the loan type's behaviour.
*/
constructor(
address _nftfiHub,
address _admin,
string[] memory _offerTypes,
address[] memory _loanContracts
) Ownable(_admin) {
hub = INftfiHub(_nftfiHub);
_deployer = msg.sender;
_registerOfferTypes(_offerTypes, _loanContracts);
}
/**
* @dev Sets `promissoryNoteToken` and `obligationReceiptToken`.
* It can be executed once by the deployer.
*
* @param _promissoryNoteToken - Promissory Note Token address
* @param _obligationReceiptToken - Obligaiton Recipt Token address
*/
function initialize(address _promissoryNoteToken, address _obligationReceiptToken) external {
if (msg.sender != _deployer) revert OnlyDeployer();
if (_initialized) revert AlreadyInitialized();
if (_promissoryNoteToken == address(0)) revert PromissoryNoteZeroAddress();
if (_obligationReceiptToken == address(0)) revert ObligationReceiptZeroAddress();
_initialized = true;
promissoryNoteToken = _promissoryNoteToken;
obligationReceiptToken = _obligationReceiptToken;
}
/**
* @dev This is called by the OfferType beginning the new loan.
* It initialize the new loan data, and returns the new loan id.
*/
function registerLoan() external override onlyInitialized returns (uint32) {
address loanContract = msg.sender;
if (_typeOfLoanContract[loanContract] == bytes32(0)) revert NotRegisteredLoanContract();
if (_isLoanContractDisabled[loanContract]) revert DisabledLoanContract();
// (loanIds start at 1)
totalNumLoans += 1;
Loan memory newLoan = Loan({status: StatusType.NEW, loanContract: loanContract, smartNftId: 0});
loans[totalNumLoans] = newLoan;
emit UpdateStatus(totalNumLoans, loanContract, StatusType.NEW);
return totalNumLoans;
}
/**
* @notice Mints a Promissory Note SmartNFT for the lender. Must be called by corresponding loan type
*
* @param _loanId - The ID of the loan.
* @param _lender - The address of the lender.
*/
function mintPromissoryNote(uint32 _loanId, address _lender) external onlyInitialized {
address loanContract = msg.sender;
if (_typeOfLoanContract[loanContract] == bytes32(0)) revert NotRegisteredLoanContract();
// create smartNFTid to match the id of the promissory note if promissory note doens't exist
uint64 smartNftId = loans[_loanId].smartNftId;
if (smartNftId == 0) {
smartNftIdCounter += 1;
smartNftId = uint64(uint256(keccak256(abi.encodePacked(address(this), smartNftIdCounter))));
}
if (loans[_loanId].status != StatusType.NEW) revert LoanStatusMustBeNEW();
if (SmartNft(promissoryNoteToken).exists(smartNftId)) revert PromissoryNoteAlreadyExists();
loans[_loanId].smartNftId = smartNftId;
// Issue an ERC721 promissory note to the lender that gives them the
// right to either the principal-plus-interest or the collateral.
SmartNft(promissoryNoteToken).mint(_lender, smartNftId, abi.encode(_loanId));
}
/**
* @notice Mints an Obligation Receipt SmartNFT for the borrower. Must be called by corresponding loan type
*
* @param _loanId - The ID of the loan.
* @param _borrower - The address of the borrower.
*/
function mintObligationReceipt(uint32 _loanId, address _borrower) external override onlyInitialized {
address loanContract = msg.sender;
if (_typeOfLoanContract[loanContract] == bytes32(0)) revert NotRegisteredLoanContract();
// create smartNFTid to match the id of the promissory note if promissory note doens't exist
uint64 smartNftId = loans[_loanId].smartNftId;
if (smartNftId == 0) {
smartNftIdCounter += 1;
smartNftId = uint64(uint256(keccak256(abi.encodePacked(address(this), smartNftIdCounter))));
}
if (loans[_loanId].status != StatusType.NEW) revert LoanStatusMustBeNEW();
if (SmartNft(obligationReceiptToken).exists(smartNftId)) revert ObligationReceiptAlreadyExists();
loans[_loanId].smartNftId = smartNftId;
// Issue an ERC721 obligation receipt to the borrower that gives them the
// right to pay back the loan and get the collateral back.
SmartNft(obligationReceiptToken).mint(_borrower, smartNftId, abi.encode(_loanId));
}
/**
* @notice Resets the SmartNFTs associated with a loan.
*
* @param _loanId - The ID of the loan.
*/
function resetSmartNfts(uint32 _loanId) external override onlyInitialized {
address loanContract = msg.sender;
if (_typeOfLoanContract[loanContract] == bytes32(0)) revert NotRegisteredLoanContract();
uint64 oldSmartNftId = loans[_loanId].smartNftId;
if (loans[_loanId].status != StatusType.NEW) revert LoanStatusMustBeNEW();
if (SmartNft(promissoryNoteToken).exists(oldSmartNftId)) {
SmartNft(promissoryNoteToken).burn(oldSmartNftId);
}
if (SmartNft(obligationReceiptToken).exists(oldSmartNftId)) {
SmartNft(obligationReceiptToken).burn(oldSmartNftId);
}
}
/**
* @dev This is called by the OfferType who created the loan, when a loan is resolved whether by paying back or
* liquidating the loan.
* It sets the loan as `RESOLVED` and burns both PromossoryNote and ObligationReceipt SmartNft's.
*
* @param _loanId - Id of the loan
*/
function resolveLoan(uint32 _loanId, bool _repaid) external override onlyInitialized {
Loan storage loan = loans[_loanId];
if (loan.status != StatusType.NEW) revert LoanStatusMustBeNEW();
if (loan.loanContract != msg.sender) revert CallerNotLoanCreatorContract();
if (_repaid) {
loan.status = StatusType.REPAID;
} else {
loan.status = StatusType.LIQUIDATED;
}
if (SmartNft(promissoryNoteToken).exists(loan.smartNftId)) {
SmartNft(promissoryNoteToken).burn(loan.smartNftId);
}
if (SmartNft(obligationReceiptToken).exists(loan.smartNftId)) {
SmartNft(obligationReceiptToken).burn(loan.smartNftId);
}
emit UpdateStatus(_loanId, msg.sender, loan.status);
}
/**
* @dev Returns loan's data for a given id.
*
* @param _loanId - Id of the loan
*/
function getLoanData(uint32 _loanId) external view override returns (Loan memory) {
return loans[_loanId];
}
/**
* @dev Returns loan's data and offerType for a given loan id.
*
* @param _loanId - Id of the loan
*/
function getLoanDataAndOfferType(uint32 _loanId) external view returns (Loan memory, bytes32) {
Loan memory loan = loans[_loanId];
return (loan, _typeOfLoanContract[loan.loanContract]);
}
/**
* @dev checks if the given id is valid for the given loan contract address
* @param _loanId - Id of the loan
* @param _loanContract - address og the loan contract
*/
function isValidLoanId(uint32 _loanId, address _loanContract) external view override returns (bool validity) {
validity = loans[_loanId].loanContract == _loanContract;
}
/**
* @notice Set or update the contract address that implements the given Loan Type.
* Set address(0) for a loan type for un-register such type.
*
* @param _offerType - Loan type represented by 'loan type'.
* @param _loanContract - The address of the wrapper contract that implements the loan type's behaviour.
*/
function registerOfferType(string memory _offerType, address _loanContract) external onlyOwner {
_registerOfferType(_offerType, _loanContract);
}
/**
* @notice Deletes the contract address associated with a given Loan Type.
*
* @param _offerType - Loan type represented by 'loan type'.
* @param _loanContract - The address of the wrapper contract to be deleted.
*/
function deleteOfferType(string memory _offerType, address _loanContract) external onlyOwner {
bytes32 offerTypeKey = ContractKeyUtils.getIdFromStringKey(_offerType);
delete _typeOfLoanContract[_loanContract];
if (_defaultLoanContractForOfferType[offerTypeKey] == _loanContract) {
delete _defaultLoanContractForOfferType[offerTypeKey];
}
}
/**
* @notice Disables a loan contract. Makes it impossible for a loan contract to register a new loan,
* altough renegotiations of their existing loans and repayment/liquidations are still possible
*
* @param _loanContract - The address of the loan contract to be disabled.
*/
function disableLoanContract(address _loanContract) external onlyOwner {
_isLoanContractDisabled[_loanContract] = true;
}
/**
* @notice Enables a loan contract.
*
* @param _loanContract - The address of the loan contract to be enabled.
*/
function enableLoanContract(address _loanContract) external onlyOwner {
_isLoanContractDisabled[_loanContract] = false;
}
/**
* @notice Batch set or update the contract addresses that implement the given batch Loan Type.
* Set address(0) for a loan type for un-register such type.
*
* @param _offerTypes - Loan types represented by 'loan type'.
* @param _loanContracts - The addresses of each wrapper contract that implements the loan type's behaviour.
*/
function registerOfferTypes(string[] memory _offerTypes, address[] memory _loanContracts) external onlyOwner {
_registerOfferTypes(_offerTypes, _loanContracts);
}
/**
* @notice This function can be called by anyone to get the latest
* contract address that implements the given loan type.
*
* @param _offerType - The loan type, e.g. bytes32("ASSET_OFFER_LOAN")
*/
function getDefaultLoanContractForOfferType(bytes32 _offerType) public view override returns (address) {
return _defaultLoanContractForOfferType[_offerType];
}
/**
* @notice This function can be called by anyone to get the loan type of the given contract address.
*
* @param _loanContract - The loan contract
*/
function getTypeOfLoanContract(address _loanContract) public view override returns (bytes32) {
return _typeOfLoanContract[_loanContract];
}
/**
* @notice Checks if a loan contract is disabled.
*
* @param _loanContract - The loan contract address.
* @return bool - True if disabled, false otherwise.
*/
function isLoanContractDisabled(address _loanContract) external view returns (bool) {
return _isLoanContractDisabled[_loanContract];
}
/**
* @notice Set or update the contract address that implements the given Loan Type.
* Set address(0) for a loan type for un-register such type.
*
* @param _offerType - Loan type represented by 'loan type').
* @param _loanContract - The address of the wrapper contract that implements the loan type's behaviour.
*/
function _registerOfferType(string memory _offerType, address _loanContract) internal {
if (bytes(_offerType).length == 0) revert OfferTypeIsEmpty();
bytes32 offerTypeKey = ContractKeyUtils.getIdFromStringKey(_offerType);
// delete loan contract address of old typeKey registered to this loan contract address
if (_typeOfLoanContract[_loanContract] != bytes32(0)) revert LoanContractAlreadyRegistered();
_defaultLoanContractForOfferType[offerTypeKey] = _loanContract;
_typeOfLoanContract[_loanContract] = offerTypeKey;
emit TypeUpdated(offerTypeKey, _loanContract);
}
/**
* @notice Batch set or update the contract addresses that implement the given batch Loan Type.
* Set address(0) for a loan type for un-register such type.
*
* @param _offerTypes - Loan types represented by keccak256('loan type').
* @param _loanContracts - The addresses of each wrapper contract that implements the loan type's behaviour.
*/
function _registerOfferTypes(string[] memory _offerTypes, address[] memory _loanContracts) internal {
if (_offerTypes.length != _loanContracts.length) revert FunctionInformationArityMismatch();
for (uint256 i; i < _offerTypes.length; ++i) {
_registerOfferType(_offerTypes[i], _loanContracts[i]);
}
}
/**
* @notice This function can be called by either a lender or a borrower to cancel all off-chain orders that they
* have signed that contain this nonce. If the off-chain orders were created correctly, there should only be one
* off-chain order that contains this nonce at all.
*
* The nonce referred to here is not the same as an Ethereum account's nonce. We are referring
* instead to nonces that are used by both the lender and the borrower when they are first signing off-chain NFTfi
* orders. These nonces can be any uint256 value that the user has not previously used to sign an off-chain order.
* Each nonce can be used at most once per user within NFTfi, regardless of whether they are the lender or the
* borrower in that situation. This serves two purposes. First, it prevents replay attacks where an attacker would
* submit a user's off-chain order more than once. Second, it allows a user to cancel an off-chain order by calling
* NFTfi.cancelLoanCommitment(), which marks the nonce as used and prevents any future loan from
* using the user's off-chain order that contains that nonce.
*
* @param _nonce - User nonce
*/
function cancelLoanCommitment(bytes32 _offerType, uint256 _nonce) external {
if (_nonceHasBeenUsedForUserByOfferType[_offerType][msg.sender][_nonce]) {
revert InvalidNonce();
}
_nonceHasBeenUsedForUserByOfferType[_offerType][msg.sender][_nonce] = true;
}
/**
* @notice This function can be used to view whether a particular nonce for a particular user has already been used,
* either from a successful loan or a cancelled off-chain order.
*
* @param _user - The address of the user. This function works for both lenders and borrowers alike.
* @param _nonce - The nonce referred to here is not the same as an Ethereum account's nonce. We are referring
* instead to nonces that are used by both the lender and the borrower when they are first signing off-chain
* NFTfi orders. These nonces can be any uint256 value that the user has not previously used to sign an off-chain
* order. Each nonce can be used at most once per user within NFTfi, regardless of whether they are the lender or
* the borrower in that situation. This serves two purposes:
* - First, it prevents replay attacks where an attacker would submit a user's off-chain order more than once.
* - Second, it allows a user to cancel an off-chain order by calling NFTfi.cancelLoanCommitment()
* , which marks the nonce as used and prevents any future loan from using the user's off-chain order that contains
* that nonce.
*
* @return A bool representing whether or not this nonce has been used for this user.
*/
function getWhetherNonceHasBeenUsedForUser(
bytes32 _offerType,
address _user,
uint256 _nonce
) external view returns (bool) {
return _nonceHasBeenUsedForUserByOfferType[_offerType][_user][_nonce];
}
/**
* @notice Checks if a nonce is valid.
*
* @param _user - The address of the user.
* @param _nonce - The nonce to be checked.
*/
function checkNonce(address _user, uint256 _nonce) public view override {
bytes32 offerType = _typeOfLoanContract[msg.sender];
if (_nonceHasBeenUsedForUserByOfferType[offerType][_user][_nonce]) {
revert InvalidNonce();
}
}
/**
* @notice Checks and invalidates a nonce for a user.
*
* @param _user - The address of the user.
* @param _nonce - The nonce to be checked and invalidated.
*/
function checkAndInvalidateNonce(address _user, uint256 _nonce) external override {
bytes32 offerType = _typeOfLoanContract[msg.sender];
if (_nonceHasBeenUsedForUserByOfferType[offerType][_user][_nonce]) {
revert InvalidNonce();
}
_nonceHasBeenUsedForUserByOfferType[offerType][_user][_nonce] = true;
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {
ILoanCoordinator,
LoanBaseMinimal,
NFTfiSigningUtils,
LoanChecksAndCalculations,
LoanData
} from "./LoanBaseMinimal.sol";
import {ContractKeyUtils} from "../../utils/ContractKeyUtils.sol";
/**
* @title AssetOfferLoan
* @author NFTfi
* @notice Main contract for NFTfi Loans Type. This contract manages the ability to create NFT-backed
* peer-to-peer loans of type Fixed (agreed to be a fixed-repayment loan) where the borrower pays the
* maximumRepaymentAmount regardless of whether they repay early or not.
*
* There are two ways to commence an NFT-backed loan:
*
* a. The borrower accepts a lender's offer by calling `acceptOffer`.
* 1. the borrower calls nftContract.approveAll(NFTfi), approving the NFTfi contract to move their NFT's on their
* behalf.
* 2. the lender calls erc20Contract.approve(NFTfi), allowing NFTfi to move the lender's ERC20 tokens on their
* behalf.
* 3. the lender signs an off-chain message, proposing its offer terms.
* 4. the borrower calls `acceptOffer` to accept these terms and enter into the loan. The NFT is stored in
* the contract, the borrower receives the loan principal in the specified ERC20 currency, the lender can mint an
* NFTfi promissory note (in ERC721 form) that represents the rights to either the principal-plus-interest, or the
* underlying NFT collateral if the borrower does not pay back in time, and the borrower can mint an obligation receipt
* (in ERC721 form) that gives them the right to pay back the loan and get the collateral back.
*
* The lender can freely transfer and trade this ERC721 promissory note as they wish, with the knowledge that
* transferring the ERC721 promissory note tranfers the rights to principal-plus-interest and/or collateral, and that
* they will no longer have a claim on the loan. The ERC721 promissory note itself represents that claim.
*
* The borrower can freely transfer and trade this ERC721 obligation receipt as they wish, with the knowledge that
* transferring the ERC721 obligation receipt tranfers the rights right to pay back the loan and get the collateral
* back.
*
*
* A loan may end in one of two ways:
* - First, a borrower may call NFTfi.payBackLoan() and pay back the loan plus interest at any time, in which case they
* receive their NFT back in the same transaction.
* - Second, if the loan's duration has passed and the loan has not been paid back yet, a lender can call
* NFTfi.liquidateOverdueLoan(), in which case they receive the underlying NFT collateral and forfeit the rights to the
* principal-plus-interest, which the borrower now keeps.
*/
contract AssetOfferLoan is LoanBaseMinimal {
/* ************* */
/* CUSTOM ERRORS */
/* ************* */
error InvalidLenderSignature();
error NegativeInterestRate();
error OriginationFeeIsTooHigh();
/* *********** */
/* CONSTRUCTOR */
/* *********** */
/**
* @dev Sets `hub` and permitted erc20-s
*
* @param _admin - Initial admin of this contract.
* @param _nftfiHub - NFTfiHub address
* @param _permittedErc20s - list of permitted ERC20 token contract addresses
*/
constructor(
address _admin,
address _nftfiHub,
address[] memory _permittedErc20s
) LoanBaseMinimal(_admin, _nftfiHub, ContractKeyUtils.getIdFromStringKey("LOAN_COORDINATOR"), _permittedErc20s) {
// solhint-disable-previous-line no-empty-blocks
}
/* ********* */
/* FUNCTIONS */
/* ********* */
/**
* @notice This function is called by the borrower when accepting a lender's offer to begin a loan.
*
* @param _offer - The offer made by the lender.
* @param _signature - The components of the lender's signature.
* @return The ID of the created loan.
*/
function acceptOffer(
Offer memory _offer,
Signature memory _signature
) external virtual whenNotPaused nonReentrant returns (uint32) {
address nftWrapper = _getWrapper(_offer.nftCollateralContract);
_loanSanityChecks(_offer, nftWrapper);
_loanSanityChecksOffer(_offer);
return _acceptOffer(_setupLoanTerms(_offer, _signature.signer, nftWrapper), _offer, _signature);
}
/* ******************* */
/* READ-ONLY FUNCTIONS */
/* ******************* */
/**
* @notice This function can be used to view the current quantity of the ERC20 currency used in the specified loan
* required by the borrower to repay their loan, measured in the smallest unit of the ERC20 currency. Note that
* since interest accrues every second, once a borrower calls repayLoan(), the amount will have increased slightly.
*
* @param _loanId A unique identifier for this particular loan, sourced from the Loan Coordinator.
*
* @return The amount of the specified ERC20 currency required to pay back this loan, measured in the smallest unit
* of the specified ERC20 currency.
*/
function getPayoffAmount(uint32 _loanId) external view override returns (uint256) {
LoanTerms memory loan = loanIdToLoan[_loanId];
uint256 loanDurationSoFarInSeconds = block.timestamp - uint256(loan.loanStartTime);
uint256 interestDue = _computeInterestDue(
loan.loanPrincipalAmount,
loan.maximumRepaymentAmount,
loanDurationSoFarInSeconds,
uint256(loan.loanDuration),
loan.isProRata
);
return (loan.loanPrincipalAmount) + interestDue;
}
/* ****************** */
/* INTERNAL FUNCTIONS */
/* ****************** */
/**
* @notice This function is called by the borrower when accepting a lender's offer to begin a loan.
*
* @param _loanTerms - The main Loan Terms struct. This data is saved upon loan creation on loanIdToLoan.
* @param _offer - The offer made by the lender.
* @param _signature - The components of the lender's signature.
* @return The ID of the created loan.
*/
function _acceptOffer(
LoanTerms memory _loanTerms,
Offer memory _offer,
Signature memory _signature
) internal virtual returns (uint32) {
// Check loan nonces. These are different from Ethereum account nonces.
// Here, these are uint256 numbers that should uniquely identify
// each signature for each user (i.e. each user should only create one
// off-chain signature for each nonce, with a nonce being any arbitrary
// uint256 value that they have not used yet for an off-chain NFTfi
// signature).
ILoanCoordinator(hub.getContract(LOAN_COORDINATOR)).checkAndInvalidateNonce(
_signature.signer,
_signature.nonce
);
bytes32 offerType = _getOwnOfferType();
if (!NFTfiSigningUtils.isValidLenderSignature(_offer, _signature, offerType)) {
revert InvalidLenderSignature();
}
uint32 loanId = _createLoan(_loanTerms, msg.sender);
// Emit an event with all relevant details from this transaction.
emit LoanStarted(loanId, msg.sender, _signature.signer, _loanTerms);
return loanId;
}
/**
* @dev Creates a `LoanTerms` struct using data sent as the lender's `_offer` on `acceptOffer`.
* This is needed in order to avoid stack too deep issues.
*
* @param _offer - The offer made by the lender.
* @param _lender - The address of the lender.
* @param _nftWrapper - The address of the NFT wrapper contract.
* @return The `LoanTerms` struct.
*/
function _setupLoanTerms(
Offer memory _offer,
address _lender,
address _nftWrapper
) internal view returns (LoanTerms memory) {
return
LoanTerms({
loanERC20Denomination: _offer.loanERC20Denomination,
loanPrincipalAmount: _offer.loanPrincipalAmount,
maximumRepaymentAmount: _offer.maximumRepaymentAmount,
nftCollateralContract: _offer.nftCollateralContract,
nftCollateralWrapper: _nftWrapper,
nftCollateralId: _offer.nftCollateralId,
loanStartTime: uint64(block.timestamp),
loanDuration: _offer.loanDuration,
loanInterestRateForDurationInBasisPoints: uint16(0),
loanAdminFeeInBasisPoints: adminFeeInBasisPoints,
borrower: msg.sender,
lender: _lender,
escrow: getEscrowAddress(msg.sender),
isProRata: _offer.isProRata,
originationFee: _offer.originationFee
});
}
/**
* @dev Calculates the interest rate for the loan based on principal amount and maximum repayment amount.
*
* @param _loanPrincipalAmount - The principal amount of the loan.
* @param _maximumRepaymentAmount - The maximum repayment amount of the loan.
* @return The interest rate for the duration of the loan in basis points.
*/
function _calculateInterestRateForDurationInBasisPoints(
uint256 _loanPrincipalAmount,
uint256 _maximumRepaymentAmount,
bool _isProRata
) internal pure returns (uint256) {
if (!_isProRata) {
return 0;
} else {
uint256 interest = _maximumRepaymentAmount - _loanPrincipalAmount;
return (interest * HUNDRED_PERCENT) / _loanPrincipalAmount;
}
}
/**
* @dev Calculates the payoff amount and admin fee for the loan.
*
* @param _loan - Struct containing all the loan's parameters.
* @return adminFee - The admin fee.
* @return payoffAmount - The payoff amount.
*/
function _payoffAndFee(
LoanTerms memory _loan
) internal view override returns (uint256 adminFee, uint256 payoffAmount) {
// Calculate amounts to send to lender and admins
uint256 interestDue = _computeInterestDue(
_loan.loanPrincipalAmount,
_loan.maximumRepaymentAmount,
block.timestamp - uint256(_loan.loanStartTime),
uint256(_loan.loanDuration),
_loan.isProRata
);
adminFee = LoanChecksAndCalculations.computeAdminFee(interestDue, uint256(_loan.loanAdminFeeInBasisPoints));
payoffAmount = ((_loan.loanPrincipalAmount) + interestDue) - adminFee;
}
/**
* @notice A convenience function that calculates the amount of interest currently due for a given loan. The
* interest is capped at _maximumRepaymentAmount minus _loanPrincipalAmount.
*
* @param _loanPrincipalAmount - The total quantity of principal first loaned to the borrower, measured in the
* smallest units of the ERC20 currency used for the loan.
* @param _maximumRepaymentAmount - The maximum amount of money that the borrower would be required to retrieve
* their collateral. If interestIsProRated is set to false, then the borrower will always have to pay this amount to
* retrieve their collateral.
* @param _loanDurationSoFarInSeconds - The elapsed time (in seconds) that has occurred so far since the loan began
* until repayment.
* @param _loanTotalDurationAgreedTo - The original duration that the borrower and lender agreed to, by which they
* measured the interest that would be due.
*
* @return The quantity of interest due, measured in the smallest units of the ERC20 currency used to pay this loan.
*/
function _computeInterestDue(
uint256 _loanPrincipalAmount,
uint256 _maximumRepaymentAmount,
uint256 _loanDurationSoFarInSeconds,
uint256 _loanTotalDurationAgreedTo,
bool _isProRata
) internal pure returns (uint256) {
// is it fixed?
if (!_isProRata) {
return _maximumRepaymentAmount - _loanPrincipalAmount;
} else {
uint256 interestDueAfterEntireDurationInBasisPoints = (_loanPrincipalAmount *
_calculateInterestRateForDurationInBasisPoints(
_loanPrincipalAmount,
_maximumRepaymentAmount,
_isProRata
));
uint256 interestDueAfterElapsedDuration = (interestDueAfterEntireDurationInBasisPoints *
_loanDurationSoFarInSeconds) /
_loanTotalDurationAgreedTo /
uint256(HUNDRED_PERCENT);
if (_loanPrincipalAmount + interestDueAfterElapsedDuration > _maximumRepaymentAmount) {
return (_maximumRepaymentAmount - _loanPrincipalAmount);
} else {
return interestDueAfterElapsedDuration;
}
}
}
/**
* @dev Performs validation checks on loan parameters when accepting an offer.
*
* @param _offer - The offer made by the lender.
*/
function _loanSanityChecksOffer(LoanData.Offer memory _offer) internal pure {
if (_offer.maximumRepaymentAmount < _offer.loanPrincipalAmount) {
revert NegativeInterestRate();
}
if (_offer.originationFee >= _offer.loanPrincipalAmount) {
revert OriginationFeeIsTooHigh();
}
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {LoanData} from "./LoanData.sol";
interface ILoanBase {
function maximumLoanDuration() external view returns (uint256);
function adminFeeInBasisPoints() external view returns (uint16);
// solhint-disable-next-line func-name-mixedcase
function LOAN_COORDINATOR() external view returns (bytes32);
function getLoanTerms(uint32) external view returns (LoanData.LoanTerms memory);
function loanRepaidOrLiquidated(uint32) external view returns (bool);
function getWhetherRenegotiationNonceHasBeenUsedForUser(address _user, uint256 _nonce) external view returns (bool);
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {ILoanBase} from "./ILoanBase.sol";
import {LoanData} from "./LoanData.sol";
import {LoanChecksAndCalculations} from "./LoanChecksAndCalculations.sol";
import {BaseLoan} from "../BaseLoan.sol";
import {NFTfiSigningUtils} from "../../utils/NFTfiSigningUtils.sol";
import {INftfiHub} from "../../interfaces/INftfiHub.sol";
import {ContractKeys} from "../../utils/ContractKeys.sol";
import {ContractKeyUtils} from "../../utils/ContractKeyUtils.sol";
import {ILoanCoordinator} from "../../interfaces/ILoanCoordinator.sol";
import {IPermittedERC20s} from "../../interfaces/IPermittedERC20s.sol";
import {IPermittedNFTs} from "../../interfaces/IPermittedNFTs.sol";
import {IEscrow} from "../../interfaces/IEscrow.sol";
import {IERC20TransferManager} from "../../interfaces/IERC20TransferManager.sol";
import {IPersonalEscrow} from "../../interfaces/IPersonalEscrow.sol";
import {PersonalEscrowFactory} from "../../escrow/PersonalEscrowFactory.sol";
import {INftWrapper} from "../../interfaces/INftWrapper.sol";
import {IDelegateCashPlugin} from "../../interfaces/IDelegateCashPlugin.sol";
import {Address} from "@openzeppelin/contracts/utils/Address.sol";
import {IERC721} from "@openzeppelin/contracts/token/ERC721/IERC721.sol";
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
/**
* @title LoanBaseMinimal
* @author NFTfi
* @notice Main contract for NFTfi Loan Type. This contract manages the ability to create NFT-backed
* peer-to-peer loans.
*
* There are two ways to commence an NFT-backed loan:
*
* a. The borrower accepts a lender's offer by calling `acceptOffer`.
* 1. the borrower calls nftContract.approveAll(NFTfi), approving the NFTfi contract to move their NFT's on their
* be1alf.
* 2. the lender calls erc20Contract.approve(NFTfi), allowing NFTfi to move the lender's ERC20 tokens on their
* behalf.
* 3. the lender signs an off-chain message, proposing its offer terms.
* 4. the borrower calls `acceptOffer` to accept these terms and enter into the loan. The NFT is stored in
* the contract, the borrower receives the loan principal in the specified ERC20 currency, the lender can mint an
* NFTfi promissory note (in ERC721 form) that represents the rights to either the principal-plus-interest, or the
* underlying NFT collateral if the borrower does not pay back in time, and the borrower can mint obligation receipt
* (in ERC721 form) that gives them the right to pay back the loan and get the collateral back.
*
* The lender can freely transfer and trade this ERC721 promissory note as they wish, with the knowledge that
* transferring the ERC721 promissory note tranfers the rights to principal-plus-interest and/or collateral, and that
* they will no longer have a claim on the loan. The ERC721 promissory note itself represents that claim.
*
* The borrower can freely transfer and trade this ERC721 obligation receipt as they wish, with the knowledge that
* transferring the ERC721 obligation receipt tranfers the rights right to pay back the loan and get the collateral
* back.
*
* A loan may end in one of two ways:
* - First, a borrower may call NFTfi.payBackLoan() and pay back the loan plus interest at any time, in which case they
* receive their NFT back in the same transaction.
* - Second, if the loan's duration has passed and the loan has not been paid back yet, a lender can call
* NFTfi.liquidateOverdueLoan(), in which case they receive the underlying NFT collateral and forfeit the rights to the
* principal-plus-interest, which the borrower now keeps.
*
*
* If the loan was created as a ProRated type loan (pro-rata interest loan), then the user only pays the principal plus
* pro-rata interest if repaid early.
* However, if the loan was was created as a Fixed type loan (agreed to be a fixed-repayment loan), then the borrower
* pays the maximumRepaymentAmount regardless of whether they repay early or not.
*
*/
abstract contract LoanBaseMinimal is ILoanBase, IPermittedERC20s, BaseLoan, LoanData {
using SafeERC20 for IERC20;
/* ******* */
/* STORAGE */
/* ******* */
uint16 public constant HUNDRED_PERCENT = 10000;
// solhint-disable-next-line immutable-vars-naming
bytes32 public immutable override LOAN_COORDINATOR;
/**
* @notice The maximum duration of any loan started for this loan type, measured in seconds. This is both a
* sanity-check for borrowers and an upper limit on how long admins will have to support v1 of this contract if they
* eventually deprecate it, as well as a check to ensure that the loan duration never exceeds the space alotted for
* it in the loan struct.
*/
uint256 public override maximumLoanDuration = 365 days * 4;
/**
* @notice The percentage of interest earned by lenders on this platform that is taken by the contract admin's as a
* fee, measured in basis points (hundredths of a percent). The max allowed value is 10000.
*/
uint16 public override adminFeeInBasisPoints = 500;
/**
* @notice A mapping from a loan's identifier to the loan's details, represted by the loan struct.
*/
mapping(uint32 => LoanTerms) internal loanIdToLoan;
/**
* @notice A mapping tracking whether a loan has either been repaid or liquidated. This prevents an attacker trying
* to repay or liquidate the same loan twice.
*/
mapping(uint32 => bool) public override loanRepaidOrLiquidated;
/**
* @notice A mapping that takes both a user's address and a loan nonce that was first used when signing an off-chain
* order and checks whether that nonce has previously either been used for a loan, or has been pre-emptively
* cancelled. The nonce referred to here is not the same as an Ethereum account's nonce. We are referring instead to
* nonces that are used by both the lender and the borrower when they are first signing off-chain NFTfi orders.
*
* These nonces can be any uint256 value that the user has not previously used to sign an off-chain order. Each
* nonce can be used at most once per user within NFTfi, regardless of whether they are the lender or the borrower
* in that situation. This serves two purposes. First, it prevents replay attacks where an attacker would submit a
* user's off-chain order more than once. Second, it allows a user to cancel an off-chain order by calling
* NFTfi.cancelLoanCommitment(), which marks the nonce as used and prevents any future loan from
* using the user's off-chain order that contains that nonce.
*/
mapping(address => mapping(uint256 => bool)) internal _renegotiationNonceHasBeenUsedForUser;
/**
* @notice A mapping from an ERC20 currency address to whether that currency
* is permitted to be used by this contract.
*/
mapping(address => bool) private erc20Permits;
// solhint-disable-next-line immutable-vars-naming
INftfiHub public immutable hub;
/* ****** */
/* EVENTS */
/* ****** */
/**
* @notice This event is fired whenever the admins change the percent of interest rates earned that they charge as a
* fee. Note that newAdminFee can never exceed 10,000, since the fee is measured in basis points.
*
* @param newAdminFee - The new admin fee measured in basis points. This is a percent of the interest paid upon a
* loan's completion that go to the contract admins.
*/
event AdminFeeUpdated(uint16 newAdminFee);
/**
* @notice This event is fired whenever the admins change the maximum duration of any loan started for this loan
* type.
*
* @param newMaximumLoanDuration - The new maximum duration.
*/
event MaximumLoanDurationUpdated(uint256 newMaximumLoanDuration);
event LoanCreated(
address indexed nftCollateralContract,
uint256 indexed nftCollateralId,
address indexed recipient,
uint256 loanId
);
/**
* @notice This event is fired whenever a borrower begins a loan by calling NFTfi.beginLoan(), which can only occur
* after both the lender and borrower have approved their ERC721 and ERC20 contracts to use NFTfi, and when they
* both have signed off-chain messages that agree on the terms of the loan.
*
* @param loanId - A unique identifier for this particular loan, sourced from the Loan Coordinator.
* @param borrower - The address of the borrower.
* @param lender - The address of the lender. The lender can change their address by transferring the NFTfi ERC721
* token that they received when the loan began.
*/
event LoanStarted(uint32 indexed loanId, address indexed borrower, address indexed lender, LoanTerms loanTerms);
/**
* @notice This event is fired whenever a borrower successfully repays their loan, paying
* principal-plus-interest-minus-fee to the lender in loanERC20Denomination, paying fee to owner in
* loanERC20Denomination, and receiving their NFT collateral back.
*
* @param loanId - A unique identifier for this particular loan, sourced from the Loan Coordinator.
* @param borrower - The address of the borrower.
* @param lender - The address of the lender. The lender can change their address by transferring the NFTfi ERC721
* token that they received when the loan began.
* @param loanPrincipalAmount - The original sum of money transferred from lender to borrower at the beginning of
* the loan, measured in loanERC20Denomination's smallest units.
* @param nftCollateralId - The ID within the NFTCollateralContract for the NFT being used as collateral for this
* loan. The NFT is stored within this contract during the duration of the loan.
* @param amountPaidToLender The amount of ERC20 that the borrower paid to the lender, measured in the smalled
* units of loanERC20Denomination.
* @param adminFee The amount of interest paid to the contract admins, measured in the smalled units of
* loanERC20Denomination and determined by adminFeeInBasisPoints. This amount never exceeds the amount of interest
* earned.
* @param nftCollateralContract - The ERC721 contract of the NFT collateral
* @param loanERC20Denomination - The ERC20 contract of the currency being used as principal/interest for this
* loan.
*/
event LoanRepaid(
uint32 indexed loanId,
address indexed borrower,
address indexed lender,
uint256 loanPrincipalAmount,
uint256 nftCollateralId,
uint256 amountPaidToLender,
uint256 adminFee,
address nftCollateralContract,
address loanERC20Denomination
);
/**
* @notice This event is fired whenever a lender liquidates an outstanding loan that is owned to them that has
* exceeded its duration. The lender receives the underlying NFT collateral, and the borrower no longer needs to
* repay the loan principal-plus-interest.
*
* @param loanId - A unique identifier for this particular loan, sourced from the Loan Coordinator.
* @param borrower - The address of the borrower.
* @param lender - The address of the lender. The lender can change their address by transferring the NFTfi ERC721
* token that they received when the loan began.
* @param loanPrincipalAmount - The original sum of money transferred from lender to borrower at the beginning of
* the loan, measured in loanERC20Denomination's smallest units.
* @param nftCollateralId - The ID within the NFTCollateralContract for the NFT being used as collateral for this
* loan. The NFT is stored within this contract during the duration of the loan.
* @param loanMaturityDate - The unix time (measured in seconds) that the loan became due and was eligible for
* liquidation.
* @param loanLiquidationDate - The unix time (measured in seconds) that liquidation occurred.
* @param nftCollateralContract - The ERC721 contract of the NFT collateral
*/
event LoanLiquidated(
uint32 indexed loanId,
address indexed borrower,
address indexed lender,
uint256 loanPrincipalAmount,
uint256 nftCollateralId,
uint256 loanMaturityDate,
uint256 loanLiquidationDate,
address nftCollateralContract
);
/**
* @notice This event is fired when some of the terms of a loan are being renegotiated.
*
* @param loanId - The unique identifier for the loan to be renegotiated
* @param newLoanDuration - The new amount of time (measured in seconds) that can elapse before the lender can
* liquidate the loan and seize the underlying collateral NFT.
* @param newMaximumRepaymentAmount - The new maximum amount of money that the borrower would be required to
* retrieve their collateral, measured in the smallest units of the ERC20 currency used for the loan. The
* borrower will always have to pay this amount to retrieve their collateral, regardless of whether they repay
* early.
* @param renegotiationFee Agreed upon fee in loan denomination that borrower pays for the lender for the
* renegotiation, has to be paid with an ERC20 transfer loanERC20Denomination token, uses transfer from,
* frontend will have to prompt an erc20 approve for this from the borrower to the lender
* @param renegotiationAdminFee renegotiationFee admin portion based on determined by adminFeeInBasisPoints
* @param isProRata - indicates if a renegotiated loan is pro-rata or fixed
*/
event LoanRenegotiated(
uint32 indexed loanId,
address indexed borrower,
address indexed lender,
uint32 newLoanDuration,
uint256 newMaximumRepaymentAmount,
uint256 renegotiationFee,
uint256 renegotiationAdminFee,
bool isProRata
);
/**
* @notice This event is fired whenever the admin sets a ERC20 permit.
*
* @param erc20Contract - Address of the ERC20 contract.
* @param isPermitted - Signals ERC20 permit.
*/
event ERC20Permit(address indexed erc20Contract, bool isPermitted);
/* ************* */
/* CUSTOM ERRORS */
/* ************* */
error LoanDurationOverflow();
error BasisPointsTooHigh();
error NoTokensOwned();
error FunctionInformationArityMismatch();
error TokenIsCollateral();
error SenderNotBorrower();
error SenderNotLender();
error NoTokensInEscrow();
error LoanAlreadyRepaidOrLiquidated();
error LoanNotOverdueYet();
error OnlyLenderCanLiquidate();
error InvalidNonce();
error RenegotiationSignatureInvalid();
error ERC20ZeroAddress();
error CurrencyDenominationNotPermitted();
error NFTCollateralContractNotPermitted();
error LoanDurationExceedsMaximum();
error LoanDurationCannotBeZero();
error ZeroPrincipal();
error DelegationExists();
/* *********** */
/* CONSTRUCTOR */
/* *********** */
/**
* @dev Sets `hub`
*
* @param _admin - Initial admin of this contract.
* @param _nftfiHub - NFTfiHub address
* @param _loanCoordinatorKey -
* @param _permittedErc20s -
*/
constructor(
address _admin,
address _nftfiHub,
bytes32 _loanCoordinatorKey,
address[] memory _permittedErc20s
) BaseLoan(_admin) {
hub = INftfiHub(_nftfiHub);
LOAN_COORDINATOR = _loanCoordinatorKey;
for (uint256 i; i < _permittedErc20s.length; ++i) {
_setERC20Permit(_permittedErc20s[i], true);
}
}
/* *************** */
/* ADMIN FUNCTIONS */
/* *************** */
/**
* @notice This function can be called by admins to change the maximumLoanDuration. Note that they can never change
* maximumLoanDuration to be greater than UINT32_MAX, since that's the maximum space alotted for the duration in the
* loan struct.
*
* @param _newMaximumLoanDuration - The new maximum loan duration, measured in seconds.
*/
function updateMaximumLoanDuration(uint256 _newMaximumLoanDuration) external onlyOwner {
if (_newMaximumLoanDuration > uint256(type(uint32).max)) {
revert LoanDurationOverflow();
}
maximumLoanDuration = _newMaximumLoanDuration;
emit MaximumLoanDurationUpdated(_newMaximumLoanDuration);
}
/**
* @notice This function can be called by admins to change the percent of interest rates earned that they charge as
* a fee. Note that newAdminFee can never exceed 10,000, since the fee is measured in basis points.
*
* @param _newAdminFeeInBasisPoints - The new admin fee measured in basis points. This is a percent of the interest
* paid upon a loan's completion that go to the contract admins.
*/
function updateAdminFee(uint16 _newAdminFeeInBasisPoints) external onlyOwner {
if (_newAdminFeeInBasisPoints > HUNDRED_PERCENT) {
revert BasisPointsTooHigh();
}
adminFeeInBasisPoints = _newAdminFeeInBasisPoints;
emit AdminFeeUpdated(_newAdminFeeInBasisPoints);
}
/**
* @notice used by the owner account to be able to drain stuck NFTs
* @param _tokenAddress - address of the token contract for the token to be sent out
* @param _tokenId - id token to be sent out
* @param _receiver - receiver of the token
*/
function drainNFT(
string memory _nftType,
address _tokenAddress,
uint256 _tokenId,
address _receiver
) external onlyOwner {
bytes32 nftTypeKey = ContractKeyUtils.getIdFromStringKey(_nftType);
address transferWrapper = IPermittedNFTs(hub.getContract(ContractKeys.PERMITTED_NFTS)).getNftTypeWrapper(
nftTypeKey
);
_transferNFT(transferWrapper, _tokenAddress, _tokenId, address(this), _receiver);
}
/**
* @notice This function can be called by admins to change the permitted status of an ERC20 currency. This includes
* both adding an ERC20 currency to the permitted list and removing it.
*
* @param _erc20 - The address of the ERC20 currency whose permit list status changed.
* @param _permit - The new status of whether the currency is permitted or not.
*/
function setERC20Permit(address _erc20, bool _permit) external onlyOwner {
_setERC20Permit(_erc20, _permit);
}
/**
* @notice This function can be called by admins to change the permitted status of a batch of ERC20 currency. This
* includes both adding an ERC20 currency to the permitted list and removing it.
*
* @param _erc20s - The addresses of the ERC20 currencies whose permit list status changed.
* @param _permits - The new statuses of whether the currency is permitted or not.
*/
function setERC20Permits(address[] memory _erc20s, bool[] memory _permits) external onlyOwner {
if (_erc20s.length != _permits.length) {
revert FunctionInformationArityMismatch();
}
for (uint256 i = 0; i < _erc20s.length; ++i) {
_setERC20Permit(_erc20s[i], _permits[i]);
}
}
/**
* @notice Mints the obligation receipt for the borrower
*
* @param _loanId - The unique identifier for the loan.
*/
function mintObligationReceipt(uint32 _loanId) external nonReentrant {
LoanTerms memory loan = loanIdToLoan[_loanId];
address borrower = loan.borrower;
if (msg.sender != borrower) {
revert SenderNotBorrower();
}
_checkDelegationAndUndelegate(_loanId);
// check if colateral is in personal escrow, if yes, we need to move it to global,
// because obligation receipt can change borrower and personal escrow is tied to one borrower
if (
PersonalEscrowFactory(hub.getContract(ContractKeys.PERSONAL_ESCROW_FACTORY)).isPersonalEscrow(loan.escrow)
) {
_moveCollateralToGlobalEscrow(_loanId, loan);
}
ILoanCoordinator loanCoordinator = ILoanCoordinator(hub.getContract(LOAN_COORDINATOR));
loanCoordinator.mintObligationReceipt(_loanId, borrower);
delete loanIdToLoan[_loanId].borrower;
}
/**
* @notice Internal function to move collateral of the loan from personal tok global escrow,
* will only work if loan collateral is in personal escrow
*
* @param _loanId - The unique identifier for the loan.
* @param _loan loan terms
*/
function _moveCollateralToGlobalEscrow(uint32 _loanId, LoanTerms memory _loan) internal {
address globalEscrow = hub.getContract(ContractKeys.ESCROW);
IPersonalEscrow(_loan.escrow).handOverCollateralToEscrow(
_loan.nftCollateralWrapper,
_loan.nftCollateralContract,
_loan.nftCollateralId,
globalEscrow
);
IEscrow(globalEscrow).lockCollateral(
_loan.nftCollateralWrapper,
_loan.nftCollateralContract,
_loan.nftCollateralId,
_loan.escrow
);
loanIdToLoan[_loanId].escrow = globalEscrow;
}
/**
* @notice Mints the promissory note for the lender
*
* @param _loanId - The unique identifier for the loan.
*/
function mintPromissoryNote(uint32 _loanId) external nonReentrant {
address lender = loanIdToLoan[_loanId].lender;
if (msg.sender != lender) {
revert SenderNotLender();
}
ILoanCoordinator loanCoordinator = ILoanCoordinator(hub.getContract(LOAN_COORDINATOR));
loanCoordinator.mintPromissoryNote(_loanId, lender);
delete loanIdToLoan[_loanId].lender;
}
/**
* @dev makes possible to change loan duration and max repayment amount, loan duration even can be extended if
* loan was expired but not liquidated.
*
* @param _loanId - The unique identifier for the loan to be renegotiated
* @param _newLoanDuration - The new amount of time (measured in seconds) that can elapse before the lender can
* liquidate the loan and seize the underlying collateral NFT.
* @param _newMaximumRepaymentAmount - The new maximum amount of money that the borrower would be required to
* retrieve their collateral, measured in the smallest units of the ERC20 currency used for the loan. The
* borrower will always have to pay this amount to retrieve their collateral, regardless of whether they repay
* early.
* @param _renegotiationFee Agreed upon fee in ether that borrower pays for the lender for the renegitiation
* @param _lenderNonce - The nonce referred to here is not the same as an Ethereum account's nonce. We are
* referring instead to nonces that are used by both the lender and the borrower when they are first signing
* off-chain NFTfi orders. These nonces can be any uint256 value that the user has not previously used to sign an
* off-chain order. Each nonce can be used at most once per user within NFTfi, regardless of whether they are the
* lender or the borrower in that situation. This serves two purposes:
* - First, it prevents replay attacks where an attacker would submit a user's off-chain order more than once.
* - Second, it allows a user to cancel an off-chain order by calling NFTfi.cancelLoanCommitment()
* , which marks the nonce as used and prevents any future loan from using the user's off-chain order that contains
* that nonce.
* @param _expiry - The date when the renegotiation offer expires
* @param _isProRata - indicates if a renegotiated loan is pro-rata or fixed
* @param _lenderSignature - The ECDSA signature of the lender, obtained off-chain ahead of time, signing the
* following combination of parameters:
* - _loanId
* - _newLoanDuration
* - _isProRata
* - _newMaximumRepaymentAmount
* - _renegotiationFee
* - _lender
* - _nonce
* - _expiry
* - address of this contract
* - chainId
*/
function renegotiateLoan(
uint32 _loanId,
uint32 _newLoanDuration,
uint256 _newMaximumRepaymentAmount,
uint256 _renegotiationFee,
uint256 _lenderNonce,
uint256 _expiry,
bool _isProRata,
bytes memory _lenderSignature
) external whenNotPaused nonReentrant {
_renegotiateLoan(
_loanId,
_newLoanDuration,
_newMaximumRepaymentAmount,
_renegotiationFee,
_lenderNonce,
_expiry,
_isProRata,
_lenderSignature
);
}
/**
* @notice This function is called by a anyone to repay a loan. It can be called at any time after the loan has
* begun and before loan expiry.. The caller will pay a pro-rata portion of their interest if the loan is paid off
* early and the loan is pro-rated type, but the complete repayment amount if it is fixed type.
* The the borrower (current owner of the obligation note) will get the collaterl NFT back.
*
* This function is purposefully not pausable in order to prevent an attack where the contract admin's pause the
* contract and hold hostage the NFT's that are still within it.
*
* @param _loanId A unique identifier for this particular loan, sourced from the Loan Coordinator.
*/
function payBackLoan(uint32 _loanId) external nonReentrant {
LoanChecksAndCalculations.payBackChecks(_loanId, hub);
(
address borrower,
address lender,
LoanTerms memory loan,
ILoanCoordinator loanCoordinator
) = _getPartiesAndData(_loanId);
_payBackLoan(_loanId, borrower, lender, loan);
bool repaid = true;
_resolveLoanState(_loanId, loanCoordinator, repaid);
_resolveLoanCollateralPayback(borrower, loan);
_checkDelegationAndUndelegate(_loanId);
}
/**
* @notice This function is called by a anyone to repay a loan. It can be called at any time after the loan has
* begun and before loan expiry.. The caller will pay a pro-rata portion of their interest if the loan is paid off
* early and the loan is pro-rated type, but the complete repayment amount if it is fixed type.
* The the borrower (current owner of the obligation note) will get the collaterl NFT back.
*
* This function is purposefully not pausable in order to prevent an attack where the contract admin's pause the
* contract and hold hostage the NFT's that are still within it.
*
* @param _loanId A unique identifier for this particular loan, sourced from the Loan Coordinator.
*/
function payBackLoanSafe(uint32 _loanId) external nonReentrant {
LoanChecksAndCalculations.payBackChecks(_loanId, hub);
(
address borrower,
address lender,
LoanTerms memory loan,
ILoanCoordinator loanCoordinator
) = _getPartiesAndData(_loanId);
_payBackLoanSafe(_loanId, borrower, lender, loan);
bool repaid = true;
_resolveLoanState(_loanId, loanCoordinator, repaid);
_resolveLoanCollateralPayback(borrower, loan);
_checkDelegationAndUndelegate(_loanId);
}
/**
* @notice This function is called by a lender once a loan has finished its duration and the borrower still has not
* repaid. The lender can call this function to seize the underlying NFT collateral, although the lender gives up
* all rights to the principal-plus-collateral by doing so.
*
* This function is purposefully not pausable in order to prevent an attack where the contract admin's pause
* the contract and hold hostage the NFT's that are still within it.
*
* @param _loanId A unique identifier for this particular loan, sourced from the Loan Coordinator.
*/
function liquidateOverdueLoan(uint32 _loanId) external nonReentrant {
LoanChecksAndCalculations.checkLoanIdValidity(_loanId, hub);
// Sanity check that payBackLoan() and liquidateOverdueLoan() have never been called on this loanId.
// Depending on how the rest of the code turns out, this check may be unnecessary.
if (loanRepaidOrLiquidated[_loanId]) {
revert LoanAlreadyRepaidOrLiquidated();
}
(
address borrower,
address lender,
LoanTerms memory loan,
ILoanCoordinator loanCoordinator
) = _getPartiesAndData(_loanId);
// Ensure that the loan is indeed overdue, since we can only liquidate overdue loans.
uint256 loanMaturityDate = uint256(loan.loanStartTime) + uint256(loan.loanDuration);
if (block.timestamp <= loanMaturityDate) {
revert LoanNotOverdueYet();
}
if (msg.sender != lender) {
revert OnlyLenderCanLiquidate();
}
bool repaid = false;
_resolveLoanState(_loanId, loanCoordinator, repaid);
_resolveLoanCollateralLiquidate(lender, loan);
_checkDelegationAndUndelegate(_loanId);
// Emit an event with all relevant details from this transaction.
emit LoanLiquidated(
_loanId,
borrower,
lender,
loan.loanPrincipalAmount,
loan.nftCollateralId,
loanMaturityDate,
block.timestamp,
loan.nftCollateralContract
);
}
/**
* @notice This function can be called by either a lender or a borrower to cancel all off-chain orders that they
* have signed that contain this nonce. If the off-chain orders were created correctly, there should only be one
* off-chain order that contains this nonce at all.
*
* The nonce referred to here is not the same as an Ethereum account's nonce. We are referring
* instead to nonces that are used by both the lender and the borrower when they are first signing off-chain NFTfi
* orders. These nonces can be any uint256 value that the user has not previously used to sign an off-chain order.
* Each nonce can be used at most once per user within NFTfi, regardless of whether they are the lender or the
* borrower in that situation. This serves two purposes. First, it prevents replay attacks where an attacker would
* submit a user's off-chain order more than once. Second, it allows a user to cancel an off-chain order by calling
* NFTfi.cancelLoanCommitment(), which marks the nonce as used and prevents any future loan from
* using the user's off-chain order that contains that nonce.
*
* @param _nonce - User nonce
*/
function cancelRefinancingCommitment(uint256 _nonce) external {
if (_renegotiationNonceHasBeenUsedForUser[msg.sender][_nonce]) {
revert InvalidNonce();
}
_renegotiationNonceHasBeenUsedForUser[msg.sender][_nonce] = true;
}
/* ******************* */
/* READ-ONLY FUNCTIONS */
/* ******************* */
function getLoanTerms(uint32 _loanId) public view override returns (LoanTerms memory) {
LoanTerms memory loan = loanIdToLoan[_loanId];
return loan;
}
/**
* @notice This function can be used to view the current quantity of the ERC20 currency used in the specified loan
* required by the borrower to repay their loan, measured in the smallest unit of the ERC20 currency.
*
* @param _loanId A unique identifier for this particular loan, sourced from the Loan Coordinator.
*
* @return The amount of the specified ERC20 currency required to pay back this loan, measured in the smallest unit
* of the specified ERC20 currency.
*/
function getPayoffAmount(uint32 _loanId) external view virtual returns (uint256);
/**
* @notice This function can be used to view whether a particular nonce for a particular user has already been used,
* either from a successful loan or a cancelled off-chain order.
*
* @param _user - The address of the user. This function works for both lenders and borrowers alike.
* @param _nonce - The nonce referred to here is not the same as an Ethereum account's nonce. We are referring
* instead to nonces that are used by both the lender and the borrower when they are first signing off-chain
* NFTfi orders. These nonces can be any uint256 value that the user has not previously used to sign an off-chain
* order. Each nonce can be used at most once per user within NFTfi, regardless of whether they are the lender or
* the borrower in that situation. This serves two purposes:
* - First, it prevents replay attacks where an attacker would submit a user's off-chain order more than once.
* - Second, it allows a user to cancel an off-chain order by calling NFTfi.cancelLoanCommitment()
* , which marks the nonce as used and prevents any future loan from using the user's off-chain order that contains
* that nonce.
*
* @return A bool representing whether or not this nonce has been used for this user.
*/
function getWhetherRenegotiationNonceHasBeenUsedForUser(
address _user,
uint256 _nonce
) external view override returns (bool) {
return _renegotiationNonceHasBeenUsedForUser[_user][_nonce];
}
/**
* @notice This function can be called by anyone to get the permit associated with the erc20 contract.
*
* @param _erc20 - The address of the erc20 contract.
*
* @return Returns whether the erc20 is permitted
*/
function getERC20Permit(address _erc20) public view override returns (bool) {
return erc20Permits[_erc20];
}
/* ****************** */
/* INTERNAL FUNCTIONS */
/* ****************** */
/**
* @dev makes possible to change loan duration and max repayment amount, loan duration even can be extended if
* loan was expired but not liquidated. IMPORTANT: Frontend will have to propt the caller to do an ERC20 approve for
* the fee amount from themselves (borrower/obligation reciept holder) to the lender (promissory note holder)
*
* @param _loanId - The unique identifier for the loan to be renegotiated
* @param _newLoanDuration - The new amount of time (measured in seconds) that can elapse before the lender can
* liquidate the loan and seize the underlying collateral NFT.
* @param _newMaximumRepaymentAmount - The new maximum amount of money that the borrower would be required to
* retrieve their collateral, measured in the smallest units of the ERC20 currency used for the loan. The
* borrower will always have to pay this amount to retrieve their collateral, regardless of whether they repay
* early.
* @param _renegotiationFee Agreed upon fee in loan denomination that borrower pays for the lender and
* the admin for the renegotiation, has to be paid with an ERC20 transfer loanERC20Denomination token,
* uses transfer from, frontend will have to prompt an erc20 approve for this from the borrower to the lender,
* admin fee is calculated by the loan's loanAdminFeeInBasisPoints value
* @param _lenderNonce - The nonce referred to here is not the same as an Ethereum account's nonce. We are
* referring instead to nonces that are used by both the lender and the borrower when they are first signing
* off-chain NFTfi orders. These nonces can be any uint256 value that the user has not previously used to sign an
* off-chain order. Each nonce can be used at most once per user within NFTfi, regardless of whether they are the
* lender or the borrower in that situation. This serves two purposes:
* - First, it prevents replay attacks where an attacker would submit a user's off-chain order more than once.
* - Second, it allows a user to cancel an off-chain order by calling NFTfi.cancelLoanCommitment()
, which marks the nonce as used and prevents any future loan from using the user's off-chain order that contains
* that nonce.
* @param _expiry - The date when the renegotiation offer expires
* @param _lenderSignature - The ECDSA signature of the lender, obtained off-chain ahead of time, signing the
* following combination of parameters:
* - _loanId
* - _newLoanDuration
* - _isProRata
* - _newMaximumRepaymentAmount
* - _renegotiationFee
* - _lender
* - _nonce
* - _expiry
* - address of this contract
* - chainId
*/
function _renegotiateLoan(
uint32 _loanId,
uint32 _newLoanDuration,
uint256 _newMaximumRepaymentAmount,
uint256 _renegotiationFee,
uint256 _lenderNonce,
uint256 _expiry,
bool _isProRata,
bytes memory _lenderSignature
) internal {
LoanTerms storage loan = loanIdToLoan[_loanId];
(address borrower, address lender) = LoanChecksAndCalculations.renegotiationChecks(
loan,
_loanId,
_newLoanDuration,
_newMaximumRepaymentAmount,
_lenderNonce,
hub
);
//invalidation after check inside previous call
_renegotiationNonceHasBeenUsedForUser[lender][_lenderNonce] = true;
if (
!NFTfiSigningUtils.isValidLenderRenegotiationSignature(
_loanId,
_newLoanDuration,
_isProRata,
_newMaximumRepaymentAmount,
_renegotiationFee,
Signature({signer: lender, nonce: _lenderNonce, expiry: _expiry, signature: _lenderSignature})
)
) {
revert RenegotiationSignatureInvalid();
}
uint256 renegotiationAdminFee;
/**
* @notice Transfers fee to the lender immediately
* @dev implements Checks-Effects-Interactions pattern by modifying state only after
* the transfer happened successfully, we also add the nonReentrant modifier to
* the pbulic versions
*/
if (_renegotiationFee > 0) {
renegotiationAdminFee = LoanChecksAndCalculations.computeAdminFee(
_renegotiationFee,
loan.loanAdminFeeInBasisPoints
);
// Transfer principal-plus-interest-minus-fees from the caller (always has to be borrower) to lender
IERC20TransferManager erc20TransferManager = IERC20TransferManager(
hub.getContract(ContractKeys.ERC20_TRANSFER_MANAGER)
);
erc20TransferManager.transfer(
loan.loanERC20Denomination,
borrower,
lender,
_renegotiationFee - renegotiationAdminFee
);
// Transfer fees from the caller (always has to be borrower) to admins
erc20TransferManager.transfer(loan.loanERC20Denomination, borrower, owner(), renegotiationAdminFee);
}
loan.loanDuration = _newLoanDuration;
loan.maximumRepaymentAmount = _newMaximumRepaymentAmount;
loan.isProRata = _isProRata;
// we have to reinstate borrower record here, because obligation receipt gets deleted in reMint
if (loan.borrower == address(0) || loan.lender == address(0)) {
ILoanCoordinator(hub.getContract(LOAN_COORDINATOR)).resetSmartNfts(_loanId);
if (loan.borrower == address(0)) {
loan.borrower = borrower;
}
if (loan.lender == address(0)) {
loan.lender = lender;
}
}
emit LoanRenegotiated(
_loanId,
borrower,
lender,
_newLoanDuration,
_newMaximumRepaymentAmount,
_renegotiationFee,
renegotiationAdminFee,
_isProRata
);
}
function getEscrowAddress(address _borrower) public view returns (address) {
address personalEscrow = PersonalEscrowFactory(hub.getContract(ContractKeys.PERSONAL_ESCROW_FACTORY))
.personalEscrowOfOwner(_borrower);
if (personalEscrow != address(0)) {
return personalEscrow;
} else {
return hub.getContract(ContractKeys.ESCROW);
}
}
/**
* @dev Transfer collateral NFT from borrower to this contract and principal from lender to the borrower and
* registers the new loan through the loan coordinator.
*
* @param _loanTerms - Struct containing the loan's settings
*/
function _createLoan(LoanTerms memory _loanTerms, address _borrower) internal returns (uint32) {
IEscrow(_loanTerms.escrow).lockCollateral(
_loanTerms.nftCollateralWrapper,
_loanTerms.nftCollateralContract,
_loanTerms.nftCollateralId,
_borrower
);
uint32 loanId = _createLoanNoNftTransfer(_loanTerms, _borrower);
return loanId;
}
/**
* @dev Transfer principal from lender to the borrower and
* registers the new loan through the loan coordinator.
*
* @param _loanTerms - Struct containing the loan's settings
*/
function _createLoanNoNftTransfer(LoanTerms memory _loanTerms, address _borrower) internal returns (uint32 loanId) {
// Issue an ERC721 promissory note to the lender that gives them the
// right to either the principal-plus-interest or the collateral,
// and an obligation note to the borrower that gives them the
// right to pay back the loan and get the collateral back.
ILoanCoordinator loanCoordinator = ILoanCoordinator(hub.getContract(LOAN_COORDINATOR));
loanId = loanCoordinator.registerLoan();
// Add the loan to storage before moving collateral/principal to follow
// the Checks-Effects-Interactions pattern.
loanIdToLoan[loanId] = _loanTerms;
// Transfer principal from lender to borrower leaving origination fee.
IERC20TransferManager(hub.getContract(ContractKeys.ERC20_TRANSFER_MANAGER)).transfer(
_loanTerms.loanERC20Denomination,
_loanTerms.lender,
_borrower,
_loanTerms.loanPrincipalAmount - _loanTerms.originationFee
);
emit LoanCreated(_loanTerms.nftCollateralContract, _loanTerms.nftCollateralId, _borrower, loanId);
return loanId;
}
/**
* @notice This function is called by a anyone to repay a loan. It can be called at any time after the loan has
* begun and before loan expiry.. The caller will pay a pro-rata portion of their interest if the loan is paid off
* early and the loan is pro-rated type, but the complete repayment amount if it is fixed type.
* The the borrower (current owner of the obligation note) will get the collaterl NFT back.
*
* This function is purposefully not pausable in order to prevent an attack where the contract admin's pause the
* contract and hold hostage the NFT's that are still within it.
*
* @param _loanId A unique identifier for this particular loan, sourced from the Loan Coordinator.
*/
function _payBackLoan(uint32 _loanId, address _borrower, address _lender, LoanTerms memory _loan) internal {
// Fetch loan details from storage, but store them in memory for the sake of saving gas.
(uint256 adminFee, uint256 payoffAmount) = _payoffAndFee(_loan);
IERC20TransferManager erc20TransferManager = IERC20TransferManager(
hub.getContract(ContractKeys.ERC20_TRANSFER_MANAGER)
);
// Transfer principal-plus-interest-minus-fees from the caller to lender
erc20TransferManager.transfer(_loan.loanERC20Denomination, msg.sender, _lender, payoffAmount);
// Transfer fees from the caller to admins
erc20TransferManager.transfer(_loan.loanERC20Denomination, msg.sender, owner(), adminFee);
// Emit an event with all relevant details from this transaction.
emit LoanRepaid(
_loanId,
_borrower,
_lender,
_loan.loanPrincipalAmount,
_loan.nftCollateralId,
payoffAmount,
adminFee,
_loan.nftCollateralContract,
_loan.loanERC20Denomination
);
}
/**
* @notice This function is called by a anyone to repay a loan. It can be called at any time after the loan has
* begun and before loan expiry.. The caller will pay a pro-rata portion of their interest if the loan is paid off
* early and the loan is pro-rated type, but the complete repayment amount if it is fixed type.
* The the borrower (current owner of the obligation note) will get the collaterl NFT back.
*
* This function is purposefully not pausable in order to prevent an attack where the contract admin's pause the
* contract and hold hostage the NFT's that are still within it.
*
* @param _loanId A unique identifier for this particular loan, sourced from the Loan Coordinator.
*/
function _payBackLoanSafe(uint32 _loanId, address _borrower, address _lender, LoanTerms memory _loan) internal {
// Fetch loan details from storage, but store them in memory for the sake of saving gas.
(uint256 adminFee, uint256 payoffAmount) = _payoffAndFee(_loan);
IERC20TransferManager erc20TransferManager = IERC20TransferManager(
hub.getContract(ContractKeys.ERC20_TRANSFER_MANAGER)
);
// Transfer principal-plus-interest-minus-fees from the caller to lender
erc20TransferManager.safeLoanPaybackTransfer(_loan.loanERC20Denomination, msg.sender, _lender, payoffAmount);
// Transfer fees from the caller to admins
erc20TransferManager.safeAdminFeeTransfer(_loan.loanERC20Denomination, msg.sender, owner(), adminFee);
// Emit an event with all relevant details from this transaction.
emit LoanRepaid(
_loanId,
_borrower,
_lender,
_loan.loanPrincipalAmount,
_loan.nftCollateralId,
payoffAmount,
adminFee,
_loan.nftCollateralContract,
_loan.loanERC20Denomination
);
}
/**
* @dev Transfers several types of NFTs using a wrapper that knows how to handle each case.
*
* @param _sender - Current owner of the NFT
* @param _recipient - Recipient of the transfer
*/
function _transferNFT(
address _nftCollateralWrapper,
address _nftCollateralContract,
uint256 _nftCollateralId,
address _sender,
address _recipient
) internal {
Address.functionDelegateCall(
_nftCollateralWrapper,
abi.encodeWithSelector(
INftWrapper(_nftCollateralWrapper).transferNFT.selector,
_sender,
_recipient,
_nftCollateralContract,
_nftCollateralId
),
"NFT not successfully transferred"
);
}
function _isOwner(
address _nftCollateralWrapper,
address _nftCollateralContract,
uint256 _nftCollateralId,
address _owner
) internal returns (bool) {
bytes memory result = Address.functionDelegateCall(
_nftCollateralWrapper,
abi.encodeWithSelector(
INftWrapper(_nftCollateralWrapper).isOwner.selector,
_owner,
_nftCollateralContract,
_nftCollateralId
),
"Ownership check failed"
);
return abi.decode(result, (bool));
}
/**
* @notice A convenience function with shared functionality between `payBackLoan` and `liquidateOverdueLoan`.
*
* @param _borrower - The receiver of the collateral nft. The borrower when `payBackLoan` or the lender when
* `liquidateOverdueLoan`.
* @param _loanTerms - The main Loan Terms struct. This data is saved upon loan creation on loanIdToLoan.
*/
function _resolveLoanCollateralPayback(address _borrower, LoanTerms memory _loanTerms) internal {
address collateralContract = _loanTerms.nftCollateralContract;
uint256 collateralId = _loanTerms.nftCollateralId;
address escrow = _loanTerms.escrow;
if (PersonalEscrowFactory(hub.getContract(ContractKeys.PERSONAL_ESCROW_FACTORY)).isPersonalEscrow(escrow)) {
// borrower has a personal escrow, and the collateral is in it
IPersonalEscrow(escrow).unlockAndKeepCollateral(collateralContract, collateralId);
} else {
IEscrow(escrow).unlockCollateral(
_loanTerms.nftCollateralWrapper,
collateralContract,
collateralId,
_borrower
);
}
// invariant check here if collateral landed where it should have
}
/**
* @notice A convenience function with shared functionality between `payBackLoan` and `liquidateOverdueLoan`.
*
* @param _loanTerms - The main Loan Terms struct. This data is saved upon loan creation on loanIdToLoan.
*/
function _resolveLoanCollateralLiquidate(address _lender, LoanTerms memory _loanTerms) internal {
// Transfer collateral from this contract to the lender, since the lender is seizing collateral for an overdue
// loan
address collateralContract = _loanTerms.nftCollateralContract;
uint256 collateralId = _loanTerms.nftCollateralId;
IEscrow(_loanTerms.escrow).unlockCollateral(
_loanTerms.nftCollateralWrapper,
collateralContract,
collateralId,
_lender
);
}
function _checkDelegationAndUndelegate(uint32 _loanId) internal {
IDelegateCashPlugin delegateCashPlugin = IDelegateCashPlugin(hub.getContract(ContractKeys.DELEGATE_PLUGIN));
if (delegateCashPlugin.isCollateralDelegated(_loanId)) {
delegateCashPlugin.undelegateERC721(_loanId);
}
}
/**
* @notice Resolving the loan without transferring the nft to provide a base for the bundle
* break up of the bundled loans
*
* @param _loanId A unique identifier for this particular loan, sourced from the Loan Coordinator.
* @param _loanCoordinator - The loan coordinator used when creating the loan.
*/
function _resolveLoanState(uint32 _loanId, ILoanCoordinator _loanCoordinator, bool _repaid) internal {
// Mark loan as liquidated before doing any external transfers to follow the Checks-Effects-Interactions design
// pattern
loanRepaidOrLiquidated[_loanId] = true;
// Destroy the lender's promissory note for this loan and borrower obligation receipt
_loanCoordinator.resolveLoan(_loanId, _repaid);
}
/**
* @notice This function can be called by admins to change the permitted status of an ERC20 currency. This includes
* both adding an ERC20 currency to the permitted list and removing it.
*
* @param _erc20 - The address of the ERC20 currency whose permit list status changed.
* @param _permit - The new status of whether the currency is permitted or not.
*/
function _setERC20Permit(address _erc20, bool _permit) internal {
if (_erc20 == address(0)) {
revert ERC20ZeroAddress();
}
erc20Permits[_erc20] = _permit;
emit ERC20Permit(_erc20, _permit);
}
/**
* @dev Performs some validation checks over loan parameters
*
*/
function _loanSanityChecks(LoanData.Offer memory _offer, address _nftWrapper) internal view {
if (!getERC20Permit(_offer.loanERC20Denomination)) {
revert CurrencyDenominationNotPermitted();
}
if (_nftWrapper == address(0)) {
revert NFTCollateralContractNotPermitted();
}
if (uint256(_offer.loanDuration) > maximumLoanDuration) {
revert LoanDurationExceedsMaximum();
}
if (uint256(_offer.loanDuration) == 0) {
revert LoanDurationCannotBeZero();
}
if (_offer.loanPrincipalAmount == 0) {
revert ZeroPrincipal();
}
}
/**
* @dev reads some variable values of a loan for payback functions, created to reduce code repetition
*/
function _getPartiesAndData(
uint32 _loanId
)
internal
view
returns (address borrower, address lender, LoanTerms memory loan, ILoanCoordinator loanCoordinator)
{
loanCoordinator = ILoanCoordinator(hub.getContract(LOAN_COORDINATOR));
ILoanCoordinator.Loan memory loanCoordinatorData = loanCoordinator.getLoanData(_loanId);
uint256 smartNftId = loanCoordinatorData.smartNftId;
// Fetch loan details from storage, but store them in memory for the sake of saving gas.
loan = loanIdToLoan[_loanId];
if (loan.borrower != address(0)) {
borrower = loan.borrower;
} else {
// Fetch current owner of loan obligation note.
borrower = IERC721(loanCoordinator.obligationReceiptToken()).ownerOf(smartNftId);
}
if (loan.lender != address(0)) {
lender = loan.lender;
} else {
// Fetch current owner of loan promissory note.
lender = IERC721(loanCoordinator.promissoryNoteToken()).ownerOf(smartNftId);
}
}
/**
* @dev Calculates the payoff amount and admin fee
*/
function _payoffAndFee(LoanTerms memory _loanTerms) internal view virtual returns (uint256, uint256);
/**
* @dev Checks that the collateral is a supported contracts and returns what wrapper to use for the loan's NFT
* collateral contract.
*
* @param _nftCollateralContract - The address of the the NFT collateral contract.
*
* @return Address of the NftWrapper to use for the loan's NFT collateral.
*/
function _getWrapper(address _nftCollateralContract) internal view returns (address) {
return IPermittedNFTs(hub.getContract(ContractKeys.PERMITTED_NFTS)).getNFTWrapper(_nftCollateralContract);
}
function _getOwnOfferType() internal view returns (bytes32) {
return ILoanCoordinator(hub.getContract(LOAN_COORDINATOR)).getTypeOfLoanContract(address(this));
}
function getERC20TransferManagerAddress() public view returns (address) {
return hub.getContract(ContractKeys.ERC20_TRANSFER_MANAGER);
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {ILoanBase} from "./ILoanBase.sol";
import {LoanData} from "./LoanData.sol";
import {ILoanCoordinator} from "../../interfaces/ILoanCoordinator.sol";
import {INftfiHub} from "../../interfaces/INftfiHub.sol";
import {IERC721} from "@openzeppelin/contracts/token/ERC721/IERC721.sol";
/**
* @title LoanChecksAndCalculations
* @author NFTfi
* @notice Helper library for LoanBase
*/
library LoanChecksAndCalculations {
uint16 private constant HUNDRED_PERCENT = 10000;
/**
* @dev Function that performs some validation checks before trying to repay a loan
*
* @param _loanId - The id of the loan being repaid
*/
function payBackChecks(uint32 _loanId, INftfiHub _hub) external view {
checkLoanIdValidity(_loanId, _hub);
// Sanity check that payBackLoan() and liquidateOverdueLoan() have never been called on this loanId.
// Depending on how the rest of the code turns out, this check may be unnecessary.
// solhint-disable-next-line custom-errors
require(!ILoanBase(address(this)).loanRepaidOrLiquidated(_loanId), "Loan already repaid/liquidated");
// Fetch loan details from storage, but store them in memory for the sake of saving gas.
LoanData.LoanTerms memory lt = ILoanBase(address(this)).getLoanTerms(_loanId);
// When a loan exceeds the loan term, it is expired. At this stage the Lender can call Liquidate Loan to resolve
// the loan.
// solhint-disable-next-line custom-errors
require(block.timestamp <= (uint256(lt.loanStartTime) + uint256(lt.loanDuration)), "Loan is expired");
}
function checkLoanIdValidity(uint32 _loanId, INftfiHub _hub) public view {
// solhint-disable-next-line custom-errors
require(
ILoanCoordinator(_hub.getContract(ILoanBase(address(this)).LOAN_COORDINATOR())).isValidLoanId(
_loanId,
address(this)
),
"invalid loanId"
);
}
/**
* @dev Performs some validation checks before trying to renegotiate a loan.
* Needed to avoid stack too deep.
*
* @param _loan - The main Loan Terms struct.
* @param _loanId - The unique identifier for the loan to be renegotiated
* @param _newLoanDuration - The new amount of time (measured in seconds) that can elapse before the lender can
* liquidate the loan and seize the underlying collateral NFT.
* @param _newMaximumRepaymentAmount - The new maximum amount of money that the borrower would be required to
* retrieve their collateral, measured in the smallest units of the ERC20 currency used for the loan. The
* borrower will always have to pay this amount to retrieve their collateral, regardless of whether they repay
* early.
* @param _lenderNonce - The nonce referred to here is not the same as an Ethereum account's nonce. We are
* referring instead to nonces that are used by both the lender and the borrower when they are first signing
* off-chain NFTfi orders. These nonces can be any uint256 value that the user has not previously used to sign an
* off-chain order. Each nonce can be used at most once per user within NFTfi, regardless of whether they are the
* lender or the borrower in that situation. This serves two purposes:
* - First, it prevents replay attacks where an attacker would submit a user's off-chain order more than once.
* - Second, it allows a user to cancel an off-chain order by calling NFTfi.cancelLoanCommitment()
, which marks the nonce as used and prevents any future loan from using the user's off-chain order that contains
* that nonce.
* @return Borrower and Lender addresses
*/
function renegotiationChecks(
LoanData.LoanTerms memory _loan,
uint32 _loanId,
uint32 _newLoanDuration,
uint256 _newMaximumRepaymentAmount,
uint256 _lenderNonce,
INftfiHub _hub
) external view returns (address, address) {
checkLoanIdValidity(_loanId, _hub);
ILoanCoordinator loanCoordinator = ILoanCoordinator(
_hub.getContract(ILoanBase(address(this)).LOAN_COORDINATOR())
);
uint256 smartNftId = loanCoordinator.getLoanData(_loanId).smartNftId;
address borrower;
if (_loan.borrower != address(0)) {
borrower = _loan.borrower;
} else {
borrower = IERC721(loanCoordinator.obligationReceiptToken()).ownerOf(smartNftId);
}
// solhint-disable-next-line custom-errors
require(msg.sender == borrower, "Only borrower can initiate");
// solhint-disable-next-line custom-errors
require(block.timestamp <= (uint256(_loan.loanStartTime) + _newLoanDuration), "New duration already expired");
// solhint-disable-next-line custom-errors
require(
uint256(_newLoanDuration) <= ILoanBase(address(this)).maximumLoanDuration(),
"New duration exceeds maximum loan duration"
);
// solhint-disable-next-line custom-errors
require(!ILoanBase(address(this)).loanRepaidOrLiquidated(_loanId), "Loan already repaid/liquidated");
// solhint-disable-next-line custom-errors
require(
_newMaximumRepaymentAmount >= _loan.loanPrincipalAmount,
"Negative interest rate loans are not allowed."
);
// Fetch current owner of loan promissory note.
address lender;
if (_loan.lender != address(0)) {
lender = _loan.lender;
} else {
lender = IERC721(loanCoordinator.promissoryNoteToken()).ownerOf(smartNftId);
}
// solhint-disable-next-line custom-errors
require(
!ILoanBase(address(this)).getWhetherRenegotiationNonceHasBeenUsedForUser(lender, _lenderNonce),
"Lender nonce invalid"
);
return (borrower, lender);
}
/**
* @notice A convenience function computing the adminFee taken from a specified quantity of interest.
*
* @param _interestDue - The amount of interest due, measured in the smallest quantity of the ERC20 currency being
* used to pay the interest.
* @param _adminFeeInBasisPoints - The percent (measured in basis points) of the interest earned that will be taken
* as a fee by the contract admins when the loan is repaid. The fee is stored in the loan struct to prevent an
* attack where the contract admins could adjust the fee right before a loan is repaid, and take all of the interest
* earned.
*
* @return The quantity of ERC20 currency (measured in smalled units of that ERC20 currency) that is due as an admin
* fee.
*/
function computeAdminFee(uint256 _interestDue, uint256 _adminFeeInBasisPoints) external pure returns (uint256) {
return (_interestDue * _adminFeeInBasisPoints) / HUNDRED_PERCENT;
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
/**
* @title LoanData
* @author NFTfi
* @notice An interface containg the main Loan struct shared by Direct Loans types.
*/
interface LoanData {
/* ********** */
/* DATA TYPES */
/* ********** */
/**
* @notice The main Loan Terms struct. This data is saved upon loan creation.
*
* @param loanERC20Denomination - The address of the ERC20 contract of the currency being used as principal/interest
* for this loan.
* @param loanPrincipalAmount - The original sum of money transferred from lender to borrower at the beginning of
* the loan, measured in loanERC20Denomination's smallest units.
* @param maximumRepaymentAmount - The maximum amount of money that the borrower would be required to retrieve their
* collateral, measured in the smallest units of the ERC20 currency used for the loan.
* @param nftCollateralContract - The address of the the NFT collateral contract.
* @param nftCollateralWrapper - The NFTfi wrapper of the NFT collateral contract.
* @param nftCollateralId - The ID within the NFTCollateralContract for the NFT being used as collateral for this
* loan. The NFT is stored within this contract during the duration of the loan.
* @param loanStartTime - The block.timestamp when the loan first began (measured in seconds).
* @param loanDuration - The amount of time (measured in seconds) that can elapse before the lender can liquidate
* the loan and seize the underlying collateral NFT.
* @param loanAdminFee - The percent (measured in basis points) of the interest earned that will be
* taken as a fee by the contract admins when the loan is repaid. The fee is stored in the loan struct to prevent an
* attack where the contract admins could adjust the fee right before a loan is repaid, and take all of the interest
* earned.
* @param originationFee - The amount of tokens which will stay in lender's wallet as origination fee
* @param borrower
* @param lender
* @param escrow - address of the escrow contract the collateral is stored in
* @param isProRata - indicates if a loan is pro-rata or not
*/
struct LoanTerms {
uint256 loanPrincipalAmount;
uint256 maximumRepaymentAmount;
uint256 nftCollateralId;
address loanERC20Denomination;
uint32 loanDuration;
uint16 loanInterestRateForDurationInBasisPoints;
uint16 loanAdminFeeInBasisPoints;
uint256 originationFee;
address nftCollateralWrapper;
uint64 loanStartTime;
address nftCollateralContract;
address borrower;
address lender;
address escrow;
bool isProRata;
}
/**
* @notice The offer made by the lender. Used as parameter on both acceptOffer (initiated by the borrower)
*
* @param loanERC20Denomination - The address of the ERC20 contract of the currency being used as principal/interest
* for this loan.
* @param loanPrincipalAmount - The original sum of money transferred from lender to borrower at the beginning of
* the loan, measured in loanERC20Denomination's smallest units.
* @param maximumRepaymentAmount - The maximum amount of money that the borrower would be required to retrieve their
* collateral, measured in the smallest units of the ERC20 currency used for the loan. The borrower will always
* have to pay this amount to retrieve their collateral, regardless of whether they repay early.
* @param nftCollateralContract - The address of the ERC721 contract of the NFT collateral.
* @param nftCollateralId - The ID within the NFTCollateralContract for the NFT being used as collateral for this
* loan. The NFT is stored within this contract during the duration of the loan.
* @param loanDuration - The amount of time (measured in seconds) that can elapse before the lender can liquidate
* the loan and seize the underlying collateral NFT.
* @param isProRata - indicates if a loan is pro-rata or not
* @param originationFee - amount which will stay in lender's wallet
*/
struct Offer {
uint256 loanPrincipalAmount;
uint256 maximumRepaymentAmount;
uint256 nftCollateralId;
address nftCollateralContract;
uint32 loanDuration;
address loanERC20Denomination;
bool isProRata;
uint256 originationFee;
}
/**
* @notice Signature related params. Used as parameter on both acceptOffer (containing borrower signature)
*
* @param signer - The address of the signer. The borrower for `acceptOffer`
* @param nonce - The nonce referred here is not the same as an Ethereum account's nonce.
* We are referring instead to a nonce that is used by the lender or the borrower when they are first signing
* off-chain NFTfi orders. These nonce can be any uint256 value that the user has not previously used to sign an
* off-chain order. Each nonce can be used at most once per user within NFTfi, regardless of whether they are the
* lender or the borrower in that situation. This serves two purposes:
* - First, it prevents replay attacks where an attacker would submit a user's off-chain order more than once.
* - Second, it allows a user to cancel an off-chain order by calling NFTfi.cancelLoanCommitment()
* , which marks the nonce as used and prevents any future loan from using the user's off-chain order that contains
* that nonce.
* @param expiry - Date when the signature expires
* @param signature - The ECDSA signature of the borrower or the lender, obtained off-chain ahead of time, signing
* the following combination of parameters:
* - Lender:
* - Offer.loanERC20Denomination
* - Offer.loanPrincipalAmount
* - Offer.maximumRepaymentAmount
* - Offer.nftCollateralContract
* - Offer.nftCollateralId
* - Offer.loanDuration
* - Offer.isProRata
* - Signature.signer,
* - Signature.nonce,
* - Signature.expiry,
* - address of the loan type contract
* - chainId
*/
struct Signature {
uint256 nonce;
uint256 expiry;
address signer;
bytes signature;
}
/**
* inclusive min and max Id ranges for collection offers on collections,
* like ArtBlocks, where multiple collections are defined on one contract differentiated by id-ranges
*/
struct CollectionIdRange {
uint256 minId;
uint256 maxId;
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {ERC721} from "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import {AccessControl} from "@openzeppelin/contracts/access/AccessControl.sol";
import {Address} from "@openzeppelin/contracts/utils/Address.sol";
import {Strings} from "@openzeppelin/contracts/utils/Strings.sol";
import {INftfiHub} from "../interfaces/INftfiHub.sol";
/**
* @title SmartNft
* @author NFTfi
* @dev An ERC721 token which represents a very basic implementation of the NFTfi V2 SmartNFT.
*/
contract SmartNft is ERC721, AccessControl {
using Address for address;
using Strings for uint256;
/**
* @dev This struct contains data needed to find the loan linked to a SmartNft.
*/
struct Loan {
address loanCoordinator;
uint256 loanId;
}
/* ******* */
/* STORAGE */
/* ******* */
bytes32 public constant LOAN_COORDINATOR_ROLE = keccak256("LOAN_COORDINATOR_ROLE");
bytes32 public constant BASE_URI_ROLE = keccak256("BASE_URI_ROLE");
// solhint-disable-next-line immutable-vars-naming
INftfiHub public immutable hub;
// smartNftId => Loan
mapping(uint256 => Loan) public loans;
string public baseURI;
/**
* @dev Grants the contract the default admin role to `_admin`.
* Grants LOAN_COORDINATOR_ROLE to `_loanCoordinator`.
*
* @param _admin - Account to set as the admin of roles
* @param _nftfiHub - Address of the NftfiHub contract
* @param _loanCoordinator - Initial loan coordinator
* @param _name - Name for the SmarNFT
* @param _symbol - Symbol for the SmarNFT
* @param _customBaseURI - Base URI for the SmarNFT
*/
constructor(
address _admin,
address _nftfiHub,
address _loanCoordinator,
string memory _name,
string memory _symbol,
string memory _customBaseURI
) ERC721(_name, _symbol) {
_setupRole(DEFAULT_ADMIN_ROLE, _admin);
_setupRole(BASE_URI_ROLE, _admin);
_setupRole(LOAN_COORDINATOR_ROLE, _loanCoordinator);
_setBaseURI(_customBaseURI);
hub = INftfiHub(_nftfiHub);
}
/**
* @dev Grants LOAN_COORDINATOR_ROLE to `_account`.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*/
function setLoanCoordinator(address _account) external {
grantRole(LOAN_COORDINATOR_ROLE, _account);
}
/**
* @dev Mints a new token with `_tokenId` and assigne to `_to`.
*
* Requirements:
*
* - the caller must have `LOAN_COORDINATOR_ROLE` role.
*
* @param _to The address reciving the SmartNft
* @param _tokenId The id of the new SmartNft
* @param _data Up to the first 32 bytes contains an integer which represents the loanId linked to the SmartNft
*/
function mint(address _to, uint256 _tokenId, bytes calldata _data) external onlyRole(LOAN_COORDINATOR_ROLE) {
// solhint-disable-next-line custom-errors
require(_data.length > 0, "data must contain loanId");
uint256 loanId = abi.decode(_data, (uint256));
loans[_tokenId] = Loan({loanCoordinator: msg.sender, loanId: loanId});
_safeMint(_to, _tokenId, _data);
}
/**
* @dev Burns `_tokenId` token.
*
* Requirements:
*
* - the caller must have `LOAN_COORDINATOR_ROLE` role.
*/
function burn(uint256 _tokenId) external onlyRole(LOAN_COORDINATOR_ROLE) {
_burn(_tokenId);
}
/**
* @dev Sets baseURI.
* @param _customBaseURI - Base URI for the SmarNFT
*/
function setBaseURI(string memory _customBaseURI) external onlyRole(BASE_URI_ROLE) {
_setBaseURI(_customBaseURI);
}
function exists(uint256 _tokenId) external view returns (bool) {
return _exists(_tokenId);
}
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 _interfaceId) public view virtual override(ERC721, AccessControl) returns (bool) {
return super.supportsInterface(_interfaceId);
}
/**
* @dev Sets baseURI.
*/
function _setBaseURI(string memory _customBaseURI) internal virtual {
baseURI = bytes(_customBaseURI).length > 0
? string(abi.encodePacked(_customBaseURI, _getChainID().toString(), "/"))
: "";
}
/** @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
* token will be the concatenation of the `baseURI` and the `tokenId`.
*/
function _baseURI() internal view virtual override returns (string memory) {
return baseURI;
}
/**
* @dev This function gets the current chain ID.
*/
function _getChainID() internal view returns (uint256) {
uint256 id;
// solhint-disable-next-line no-inline-assembly
assembly {
id := chainid()
}
return id;
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
/**
* @title ContractKeys
* @author NFTfi
* @dev Common library for contract keys
*/
library ContractKeys {
bytes32 public constant PERMITTED_ERC20S = bytes32("PERMITTED_ERC20S");
bytes32 public constant PERMITTED_NFTS = bytes32("PERMITTED_NFTS");
bytes32 public constant NFT_TYPE_REGISTRY = bytes32("NFT_TYPE_REGISTRY");
bytes32 public constant LOAN_COORDINATOR = bytes32("LOAN_COORDINATOR");
bytes32 public constant PERMITTED_SNFT_RECEIVER = bytes32("PERMITTED_SNFT_RECEIVER");
bytes32 public constant ESCROW = bytes32("ESCROW");
bytes32 public constant ERC20_TRANSFER_MANAGER = bytes32("ERC20_TRANSFER_MANAGER");
bytes32 public constant PERSONAL_ESCROW_FACTORY = bytes32("PERSONAL_ESCROW_FACTORY");
bytes32 public constant DELEGATE_PLUGIN = bytes32("DELEGATE_PLUGIN");
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
/**
* @title ContractKeyUtils
* @author NFTfi
* @dev Common library for contract key utils
*/
library ContractKeyUtils {
/**
* @notice Returns the bytes32 representation of a string
* @param _key the string key
* @return id bytes32 representation
*/
function getIdFromStringKey(string memory _key) public pure returns (bytes32 id) {
// solhint-disable-next-line custom-errors
require(bytes(_key).length <= 32, "invalid key");
// solhint-disable-next-line no-inline-assembly
assembly {
id := mload(add(_key, 32))
}
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {LoanData} from "../loans/loanTypes/LoanData.sol";
import {SignatureChecker, ECDSA} from "@openzeppelin/contracts/utils/cryptography/SignatureChecker.sol";
/**
* @title NFTfiSigningUtils
* @author NFTfi
* @notice Helper contract for NFTfi. This contract manages verifying signatures from off-chain NFTfi orders.
* Based on the version of this same contract used on NFTfi V1
*/
library NFTfiSigningUtils {
/* ********* */
/* FUNCTIONS */
/* ********* */
/**
* @dev This function gets the current chain ID.
*/
function getChainID() internal view returns (uint256) {
uint256 id;
// solhint-disable-next-line no-inline-assembly
assembly {
id := chainid()
}
return id;
}
/**
* @notice This function is when the borrower accepts a lender's offer, to validate the lender's signature that the
* lender provided off-chain to verify that it did indeed made such offer.
*
* @param _offer - The offer struct containing:
* - loanERC20Denomination: The address of the ERC20 contract of the currency being used as principal/interest
* for this loan.
* - loanPrincipalAmount: The original sum of money transferred from lender to borrower at the beginning of
* the loan, measured in loanERC20Denomination's smallest units.
* - maximumRepaymentAmount: The maximum amount of money that the borrower would be required to retrieve their
* collateral, measured in the smallest units of the ERC20 currency used for the loan. The borrower will always have
* to pay this amount to retrieve their collateral, regardless of whether they repay early.
* - nftCollateralContract: The address of the ERC721 contract of the NFT collateral.
* - nftCollateralId: The ID within the NFTCollateralContract for the NFT being used as collateral for this
* loan. The NFT is stored within this contract during the duration of the loan.
* - loanDuration: The amount of time (measured in seconds) that can elapse before the lender can liquidate the
* loan and seize the underlying collateral NFT.
* - loanInterestRateForDurationInBasisPoints: This is the interest rate (measured in basis points, e.g.
* hundreths of a percent) for the loan, that must be repaid pro-rata by the borrower at the conclusion of the loan
* or risk seizure of their nft collateral. Note if the type of the loan is fixed then this value is not used and
* is irrelevant so it should be set to 0.
* - isProRata: indicates if a loan is pro-rated or fixed
* @param _signature - The signature structure containing:
* - signer: The address of the signer. The borrower for `acceptOffer`
* - nonce: The nonce referred here is not the same as an Ethereum account's nonce.
* We are referring instead to a nonce that is used by the lender or the borrower when they are first signing
* off-chain NFTfi orders. These nonce can be any uint256 value that the user has not previously used to sign an
* off-chain order. Each nonce can be used at most once per user within NFTfi, regardless of whether they are the
* lender or the borrower in that situation. This serves two purposes:
* - First, it prevents replay attacks where an attacker would submit a user's off-chain order more than once.
* - Second, it allows a user to cancel an off-chain order by calling
* NFTfi.cancelLoanCommitment(), which marks the nonce as used and prevents any future loan from
* using the user's off-chain order that contains that nonce.
* - expiry: Date when the signature expires
* - signature: The ECDSA signature of the lender, obtained off-chain ahead of time, signing the following
* @param _offerType type of the offer registered in the coordinator
* combination of parameters:
* - offer.loanERC20Denomination
* - offer.loanPrincipalAmount
* - offer.maximumRepaymentAmount
* - offer.nftCollateralContract
* - offer.nftCollateralId
* - offer.loanDuration
* - offer.isProRata
* - signature.signer,
* - signature.nonce,
* - signature.expiry,
* - _offerType
* - chainId
*/
function isValidLenderSignature(
LoanData.Offer memory _offer,
LoanData.Signature memory _signature,
bytes32 _offerType
) public view returns (bool) {
// solhint-disable-next-line custom-errors
require(block.timestamp <= _signature.expiry, "Lender Signature has expired");
if (_signature.signer == address(0)) {
return false;
} else {
bytes32 message = keccak256(
abi.encodePacked(getEncodedOffer(_offer), getEncodedSignature(_signature), _offerType, getChainID())
);
return
SignatureChecker.isValidSignatureNow(
_signature.signer,
ECDSA.toEthSignedMessageHash(message),
_signature.signature
);
}
}
/**
* @notice This function is called in renegotiateLoan() to validate the lender's signature that the lender provided
* off-chain to verify that they did indeed want to agree to this loan renegotiation according to these terms.
*
* @param _loanId - The unique identifier for the loan to be renegotiated
* @param _newLoanDuration - The new amount of time (measured in seconds) that can elapse before the lender can
* liquidate the loan and seize the underlying collateral NFT.
* @param _isProRata - indicates if loan is pro-rata or fixed
* @param _newMaximumRepaymentAmount - The new maximum amount of money that the borrower would be required to
* retrieve their collateral, measured in the smallest units of the ERC20 currency used for the loan. The
* borrower will always have to pay this amount to retrieve their collateral, regardless of whether they repay
* early.
* @param _renegotiationFee Agreed upon fee in ether that borrower pays for the lender for the renegitiation
* @param _signature - The signature structure containing:
* - signer: The address of the signer. The borrower for `acceptOffer`
* - nonce: The nonce referred here is not the same as an Ethereum account's nonce.
* We are referring instead to a nonce that is used by the lender or the borrower when they are first signing
* off-chain NFTfi orders. These nonce can be any uint256 value that the user has not previously used to sign an
* off-chain order. Each nonce can be used at most once per user within NFTfi, regardless of whether they are the
* lender or the borrower in that situation. This serves two purposes:
* - First, it prevents replay attacks where an attacker would submit a user's off-chain order more than once.
* - Second, it allows a user to cancel an off-chain order by calling NFTfi.cancelLoanCommitment()
* , which marks the nonce as used and prevents any future loan from using the user's off-chain order that contains
* that nonce.
* - expiry - The date when the renegotiation offer expires
* - lenderSignature - The ECDSA signature of the lender, obtained off-chain ahead of time, signing the
* following combination of parameters:
* - _loanId
* - _newLoanDuration
* - _isProRata
* - _newMaximumRepaymentAmount
* - _lender
* - _lenderNonce
* - _expiry
* - address of this contract
* - chainId
*/
function isValidLenderRenegotiationSignature(
uint256 _loanId,
uint32 _newLoanDuration,
bool _isProRata,
uint256 _newMaximumRepaymentAmount,
uint256 _renegotiationFee,
LoanData.Signature memory _signature
) external view returns (bool) {
return
isValidLenderRenegotiationSignature(
_loanId,
_newLoanDuration,
_isProRata,
_newMaximumRepaymentAmount,
_renegotiationFee,
_signature,
address(this)
);
}
/**
* @dev This function overload the previous function to allow the caller to specify the address of the contract
*
*/
function isValidLenderRenegotiationSignature(
uint256 _loanId,
uint32 _newLoanDuration,
bool _isProRata,
uint256 _newMaximumRepaymentAmount,
uint256 _renegotiationFee,
LoanData.Signature memory _signature,
address _loanContract
) public view returns (bool) {
// solhint-disable-next-line custom-errors
require(block.timestamp <= _signature.expiry, "Renegotiation Signature expired");
// solhint-disable-next-line custom-errors
require(_loanContract != address(0), "Loan is zero address");
if (_signature.signer == address(0)) {
return false;
} else {
bytes32 message = keccak256(
abi.encodePacked(
_loanId,
_newLoanDuration,
_isProRata,
_newMaximumRepaymentAmount,
_renegotiationFee,
getEncodedSignature(_signature),
_loanContract,
getChainID()
)
);
return
SignatureChecker.isValidSignatureNow(
_signature.signer,
ECDSA.toEthSignedMessageHash(message),
_signature.signature
);
}
}
/**
* @dev We need this to avoid stack too deep errors.
*/
function getEncodedOffer(LoanData.Offer memory _offer) internal pure returns (bytes memory) {
return
abi.encodePacked(
_offer.loanERC20Denomination,
_offer.loanPrincipalAmount,
_offer.maximumRepaymentAmount,
_offer.nftCollateralContract,
_offer.nftCollateralId,
_offer.loanDuration,
_offer.isProRata,
_offer.originationFee
);
}
/**
* @dev We need this to avoid stack too deep errors.
*/
function getEncodedSignature(LoanData.Signature memory _signature) internal pure returns (bytes memory) {
return abi.encodePacked(_signature.signer, _signature.nonce, _signature.expiry);
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {IERC1155Receiver, IERC165} from "@openzeppelin/contracts/token/ERC1155/IERC1155Receiver.sol";
import {ERC721Holder, IERC721Receiver} from "@openzeppelin/contracts/token/ERC721/utils/ERC721Holder.sol";
/**
* @title NftReceiver
* @author NFTfi
* @dev Base contract with capabilities for receiving ERC1155 and ERC721 tokens
*/
abstract contract NftReceiver is IERC1155Receiver, ERC721Holder {
/**
* @dev Handles the receipt of a single ERC1155 token type. This function is called at the end of a
* `safeTransferFrom` after the balance has been updated.
* @return `bytes4(keccak256("onERC1155Received(address,address,uint256,uint256,bytes)"))` if allowed
*/
function onERC1155Received(
address,
address,
uint256,
uint256,
bytes calldata
) external virtual override returns (bytes4) {
return this.onERC1155Received.selector;
}
/**
* @dev Handles the receipt of a multiple ERC1155 token types. This function is called at the end of a
* `safeBatchTransferFrom` after the balances have been updated.
* @return `bytes4(keccak256("onERC1155BatchReceived(address,address,uint256[],uint256[],bytes)"))` if allowed
*/
function onERC1155BatchReceived(
address,
address,
uint256[] calldata,
uint256[] calldata,
bytes calldata
) external virtual override returns (bytes4) {
// solhint-disable-next-line custom-errors
revert("ERC1155 batch not supported");
}
/**
* @dev Checks whether this contract implements the interface defined by `interfaceId`.
* @param _interfaceId Id of the interface
* @return true if this contract implements the interface
*/
function supportsInterface(bytes4 _interfaceId) public view virtual override returns (bool) {
return
_interfaceId == type(IERC1155Receiver).interfaceId ||
_interfaceId == type(IERC721Receiver).interfaceId ||
_interfaceId == type(IERC165).interfaceId;
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.19;
import {Context} from "@openzeppelin/contracts/utils/Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*
* Modified version from openzeppelin/contracts/access/Ownable.sol that allows to
* initialize the owner using a parameter in the constructor
*/
abstract contract Ownable is Context {
address private _owner;
address private _ownerCandidate;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
// solhint-disable-next-line custom-errors
require(owner() == _msgSender(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor(address _initialOwner) {
_setOwner(_initialOwner);
}
/**
* @dev Requests transferring ownership of the contract to a new account (`_newOwnerCandidate`).
* Can only be called by the current owner.
*/
function requestTransferOwnership(address _newOwnerCandidate) public virtual onlyOwner {
// solhint-disable-next-line custom-errors
require(_newOwnerCandidate != address(0), "Ownable: new owner is the zero address");
_ownerCandidate = _newOwnerCandidate;
}
function acceptTransferOwnership() public virtual {
// solhint-disable-next-line custom-errors
require(_ownerCandidate == _msgSender(), "Ownable: not owner candidate");
_setOwner(_ownerCandidate);
delete _ownerCandidate;
}
function cancelTransferOwnership() public virtual onlyOwner {
delete _ownerCandidate;
}
function rejectTransferOwnership() public virtual {
// solhint-disable-next-line custom-errors
require(_ownerCandidate == _msgSender(), "Ownable: not owner candidate");
delete _ownerCandidate;
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Sets the owner.
*/
function _setOwner(address _newOwner) internal {
address oldOwner = _owner;
_owner = _newOwner;
emit OwnershipTransferred(oldOwner, _newOwner);
}
}