Contract Name:
AccessControlledAggregator
Contract Source Code:
File 1 of 1 : AccessControlledAggregator
pragma solidity 0.6.6;
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*/
library SafeMath {
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a, "SafeMath: subtraction overflow");
uint256 c = a - b;
return c;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// Solidity only automatically asserts when dividing by 0
require(b > 0, "SafeMath: division by zero");
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
require(b != 0, "SafeMath: modulo by zero");
return a % b;
}
}
library SignedSafeMath {
int256 constant private _INT256_MIN = -2**255;
/**
* @dev Multiplies two signed integers, reverts on overflow.
*/
function mul(int256 a, int256 b) internal pure returns (int256) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
if (a == 0) {
return 0;
}
require(!(a == -1 && b == _INT256_MIN), "SignedSafeMath: multiplication overflow");
int256 c = a * b;
require(c / a == b, "SignedSafeMath: multiplication overflow");
return c;
}
/**
* @dev Integer division of two signed integers truncating the quotient, reverts on division by zero.
*/
function div(int256 a, int256 b) internal pure returns (int256) {
require(b != 0, "SignedSafeMath: division by zero");
require(!(b == -1 && a == _INT256_MIN), "SignedSafeMath: division overflow");
int256 c = a / b;
return c;
}
/**
* @dev Subtracts two signed integers, reverts on overflow.
*/
function sub(int256 a, int256 b) internal pure returns (int256) {
int256 c = a - b;
require((b >= 0 && c <= a) || (b < 0 && c > a), "SignedSafeMath: subtraction overflow");
return c;
}
/**
* @dev Adds two signed integers, reverts on overflow.
*/
function add(int256 a, int256 b) internal pure returns (int256) {
int256 c = a + b;
require((b >= 0 && c >= a) || (b < 0 && c < a), "SignedSafeMath: addition overflow");
return c;
}
/**
* @notice Computes average of two signed integers, ensuring that the computation
* doesn't overflow.
* @dev If the result is not an integer, it is rounded towards zero. For example,
* avg(-3, -4) = -3
*/
function avg(int256 _a, int256 _b)
internal
pure
returns (int256)
{
if ((_a < 0 && _b > 0) || (_a > 0 && _b < 0)) {
return add(_a, _b) / 2;
}
int256 remainder = (_a % 2 + _b % 2) / 2;
return add(add(_a / 2, _b / 2), remainder);
}
}
library Median {
using SignedSafeMath for int256;
int256 constant INT_MAX = 2**255-1;
/**
* @notice Returns the sorted middle, or the average of the two middle indexed items if the
* array has an even number of elements.
* @dev The list passed as an argument isn't modified.
* @dev This algorithm has expected runtime O(n), but for adversarially chosen inputs
* the runtime is O(n^2).
* @param list The list of elements to compare
*/
function calculate(int256[] memory list)
internal
pure
returns (int256)
{
return calculateInplace(copy(list));
}
/**
* @notice See documentation for function calculate.
* @dev The list passed as an argument may be permuted.
*/
function calculateInplace(int256[] memory list)
internal
pure
returns (int256)
{
require(0 < list.length, "list must not be empty");
uint256 len = list.length;
uint256 middleIndex = len / 2;
if (len % 2 == 0) {
int256 median1;
int256 median2;
(median1, median2) = quickselectTwo(list, 0, len - 1, middleIndex - 1, middleIndex);
return SignedSafeMath.avg(median1, median2);
} else {
return quickselect(list, 0, len - 1, middleIndex);
}
}
/**
* @notice Maximum length of list that shortSelectTwo can handle
*/
uint256 constant SHORTSELECTTWO_MAX_LENGTH = 7;
/**
* @notice Select the k1-th and k2-th element from list of length at most 7
* @dev Uses an optimal sorting network
*/
function shortSelectTwo(
int256[] memory list,
uint256 lo,
uint256 hi,
uint256 k1,
uint256 k2
)
private
pure
returns (int256 k1th, int256 k2th)
{
// Uses an optimal sorting network (https://en.wikipedia.org/wiki/Sorting_network)
// for lists of length 7. Network layout is taken from
// http://jgamble.ripco.net/cgi-bin/nw.cgi?inputs=7&algorithm=hibbard&output=svg
uint256 len = hi + 1 - lo;
int256 x0 = list[lo + 0];
int256 x1 = 1 < len ? list[lo + 1] : INT_MAX;
int256 x2 = 2 < len ? list[lo + 2] : INT_MAX;
int256 x3 = 3 < len ? list[lo + 3] : INT_MAX;
int256 x4 = 4 < len ? list[lo + 4] : INT_MAX;
int256 x5 = 5 < len ? list[lo + 5] : INT_MAX;
int256 x6 = 6 < len ? list[lo + 6] : INT_MAX;
if (x0 > x1) {(x0, x1) = (x1, x0);}
if (x2 > x3) {(x2, x3) = (x3, x2);}
if (x4 > x5) {(x4, x5) = (x5, x4);}
if (x0 > x2) {(x0, x2) = (x2, x0);}
if (x1 > x3) {(x1, x3) = (x3, x1);}
if (x4 > x6) {(x4, x6) = (x6, x4);}
if (x1 > x2) {(x1, x2) = (x2, x1);}
if (x5 > x6) {(x5, x6) = (x6, x5);}
if (x0 > x4) {(x0, x4) = (x4, x0);}
if (x1 > x5) {(x1, x5) = (x5, x1);}
if (x2 > x6) {(x2, x6) = (x6, x2);}
if (x1 > x4) {(x1, x4) = (x4, x1);}
if (x3 > x6) {(x3, x6) = (x6, x3);}
if (x2 > x4) {(x2, x4) = (x4, x2);}
if (x3 > x5) {(x3, x5) = (x5, x3);}
if (x3 > x4) {(x3, x4) = (x4, x3);}
uint256 index1 = k1 - lo;
if (index1 == 0) {k1th = x0;}
else if (index1 == 1) {k1th = x1;}
else if (index1 == 2) {k1th = x2;}
else if (index1 == 3) {k1th = x3;}
else if (index1 == 4) {k1th = x4;}
else if (index1 == 5) {k1th = x5;}
else if (index1 == 6) {k1th = x6;}
else {revert("k1 out of bounds");}
uint256 index2 = k2 - lo;
if (k1 == k2) {return (k1th, k1th);}
else if (index2 == 0) {return (k1th, x0);}
else if (index2 == 1) {return (k1th, x1);}
else if (index2 == 2) {return (k1th, x2);}
else if (index2 == 3) {return (k1th, x3);}
else if (index2 == 4) {return (k1th, x4);}
else if (index2 == 5) {return (k1th, x5);}
else if (index2 == 6) {return (k1th, x6);}
else {revert("k2 out of bounds");}
}
/**
* @notice Selects the k-th ranked element from list, looking only at indices between lo and hi
* (inclusive). Modifies list in-place.
*/
function quickselect(int256[] memory list, uint256 lo, uint256 hi, uint256 k)
private
pure
returns (int256 kth)
{
require(lo <= k);
require(k <= hi);
while (lo < hi) {
if (hi - lo < SHORTSELECTTWO_MAX_LENGTH) {
int256 ignore;
(kth, ignore) = shortSelectTwo(list, lo, hi, k, k);
return kth;
}
uint256 pivotIndex = partition(list, lo, hi);
if (k <= pivotIndex) {
// since pivotIndex < (original hi passed to partition),
// termination is guaranteed in this case
hi = pivotIndex;
} else {
// since (original lo passed to partition) <= pivotIndex,
// termination is guaranteed in this case
lo = pivotIndex + 1;
}
}
return list[lo];
}
/**
* @notice Selects the k1-th and k2-th ranked elements from list, looking only at indices between
* lo and hi (inclusive). Modifies list in-place.
*/
function quickselectTwo(
int256[] memory list,
uint256 lo,
uint256 hi,
uint256 k1,
uint256 k2
)
internal // for testing
pure
returns (int256 k1th, int256 k2th)
{
require(k1 < k2);
require(lo <= k1 && k1 <= hi);
require(lo <= k2 && k2 <= hi);
while (true) {
if (hi - lo < SHORTSELECTTWO_MAX_LENGTH) {
return shortSelectTwo(list, lo, hi, k1, k2);
}
uint256 pivotIdx = partition(list, lo, hi);
if (k2 <= pivotIdx) {
hi = pivotIdx;
} else if (pivotIdx < k1) {
lo = pivotIdx + 1;
} else {
assert(k1 <= pivotIdx && pivotIdx < k2);
k1th = quickselect(list, lo, pivotIdx, k1);
k2th = quickselect(list, pivotIdx + 1, hi, k2);
return (k1th, k2th);
}
}
}
/**
* @notice Partitions list in-place using Hoare's partitioning scheme.
* Only elements of list between indices lo and hi (inclusive) will be modified.
* Returns an index i, such that:
* - lo <= i < hi
* - forall j in [lo, i]. list[j] <= list[i]
* - forall j in [i, hi]. list[i] <= list[j]
*/
function partition(int256[] memory list, uint256 lo, uint256 hi)
private
pure
returns (uint256)
{
// We don't care about overflow of the addition, because it would require a list
// larger than any feasible computer's memory.
int256 pivot = list[(lo + hi) / 2];
lo -= 1; // this can underflow. that's intentional.
hi += 1;
while (true) {
do {
lo += 1;
} while (list[lo] < pivot);
do {
hi -= 1;
} while (list[hi] > pivot);
if (lo < hi) {
(list[lo], list[hi]) = (list[hi], list[lo]);
} else {
// Let orig_lo and orig_hi be the original values of lo and hi passed to partition.
// Then, hi < orig_hi, because hi decreases *strictly* monotonically
// in each loop iteration and
// - either list[orig_hi] > pivot, in which case the first loop iteration
// will achieve hi < orig_hi;
// - or list[orig_hi] <= pivot, in which case at least two loop iterations are
// needed:
// - lo will have to stop at least once in the interval
// [orig_lo, (orig_lo + orig_hi)/2]
// - (orig_lo + orig_hi)/2 < orig_hi
return hi;
}
}
}
/**
* @notice Makes an in-memory copy of the array passed in
* @param list Reference to the array to be copied
*/
function copy(int256[] memory list)
private
pure
returns(int256[] memory)
{
int256[] memory list2 = new int256[](list.length);
for (uint256 i = 0; i < list.length; i++) {
list2[i] = list[i];
}
return list2;
}
}
/**
* @title The Owned contract
* @notice A contract with helpers for basic contract ownership.
*/
contract Owned {
address public owner;
address private pendingOwner;
event OwnershipTransferRequested(
address indexed from,
address indexed to
);
event OwnershipTransferred(
address indexed from,
address indexed to
);
constructor() public {
owner = msg.sender;
}
/**
* @dev Allows an owner to begin transferring ownership to a new address,
* pending.
*/
function transferOwnership(address _to)
external
onlyOwner()
{
pendingOwner = _to;
emit OwnershipTransferRequested(owner, _to);
}
/**
* @dev Allows an ownership transfer to be completed by the recipient.
*/
function acceptOwnership()
external
{
require(msg.sender == pendingOwner, "Must be proposed owner");
address oldOwner = owner;
owner = msg.sender;
pendingOwner = address(0);
emit OwnershipTransferred(oldOwner, msg.sender);
}
/**
* @dev Reverts if called by anyone other than the contract owner.
*/
modifier onlyOwner() {
require(msg.sender == owner, "Only callable by owner");
_;
}
}
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*
* This library is a version of Open Zeppelin's SafeMath, modified to support
* unsigned 128 bit integers.
*/
library SafeMath128 {
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
* - Addition cannot overflow.
*/
function add(uint128 a, uint128 b) internal pure returns (uint128) {
uint128 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot overflow.
*/
function sub(uint128 a, uint128 b) internal pure returns (uint128) {
require(b <= a, "SafeMath: subtraction overflow");
uint128 c = a - b;
return c;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
* - Multiplication cannot overflow.
*/
function mul(uint128 a, uint128 b) internal pure returns (uint128) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
if (a == 0) {
return 0;
}
uint128 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function div(uint128 a, uint128 b) internal pure returns (uint128) {
// Solidity only automatically asserts when dividing by 0
require(b > 0, "SafeMath: division by zero");
uint128 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function mod(uint128 a, uint128 b) internal pure returns (uint128) {
require(b != 0, "SafeMath: modulo by zero");
return a % b;
}
}
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*
* This library is a version of Open Zeppelin's SafeMath, modified to support
* unsigned 32 bit integers.
*/
library SafeMath32 {
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
* - Addition cannot overflow.
*/
function add(uint32 a, uint32 b) internal pure returns (uint32) {
uint32 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot overflow.
*/
function sub(uint32 a, uint32 b) internal pure returns (uint32) {
require(b <= a, "SafeMath: subtraction overflow");
uint32 c = a - b;
return c;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
* - Multiplication cannot overflow.
*/
function mul(uint32 a, uint32 b) internal pure returns (uint32) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
if (a == 0) {
return 0;
}
uint32 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function div(uint32 a, uint32 b) internal pure returns (uint32) {
// Solidity only automatically asserts when dividing by 0
require(b > 0, "SafeMath: division by zero");
uint32 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function mod(uint32 a, uint32 b) internal pure returns (uint32) {
require(b != 0, "SafeMath: modulo by zero");
return a % b;
}
}
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*
* This library is a version of Open Zeppelin's SafeMath, modified to support
* unsigned 64 bit integers.
*/
library SafeMath64 {
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
* - Addition cannot overflow.
*/
function add(uint64 a, uint64 b) internal pure returns (uint64) {
uint64 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot overflow.
*/
function sub(uint64 a, uint64 b) internal pure returns (uint64) {
require(b <= a, "SafeMath: subtraction overflow");
uint64 c = a - b;
return c;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
* - Multiplication cannot overflow.
*/
function mul(uint64 a, uint64 b) internal pure returns (uint64) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
if (a == 0) {
return 0;
}
uint64 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function div(uint64 a, uint64 b) internal pure returns (uint64) {
// Solidity only automatically asserts when dividing by 0
require(b > 0, "SafeMath: division by zero");
uint64 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function mod(uint64 a, uint64 b) internal pure returns (uint64) {
require(b != 0, "SafeMath: modulo by zero");
return a % b;
}
}
interface AggregatorInterface {
function latestAnswer() external view returns (int256);
function latestTimestamp() external view returns (uint256);
function latestRound() external view returns (uint256);
function getAnswer(uint256 roundId) external view returns (int256);
function getTimestamp(uint256 roundId) external view returns (uint256);
event AnswerUpdated(int256 indexed current, uint256 indexed roundId, uint256 updatedAt);
event NewRound(uint256 indexed roundId, address indexed startedBy, uint256 startedAt);
}
interface AggregatorV3Interface {
function decimals() external view returns (uint8);
function description() external view returns (string memory);
function version() external view returns (uint256);
// getRoundData and latestRoundData should both raise "No data present"
// if they do not have data to report, instead of returning unset values
// which could be misinterpreted as actual reported values.
function getRoundData(uint80 _roundId)
external
view
returns (
uint80 roundId,
int256 answer,
uint256 startedAt,
uint256 updatedAt,
uint80 answeredInRound
);
function latestRoundData()
external
view
returns (
uint80 roundId,
int256 answer,
uint256 startedAt,
uint256 updatedAt,
uint80 answeredInRound
);
}
interface AggregatorV2V3Interface is AggregatorInterface, AggregatorV3Interface
{
}
interface AggregatorValidatorInterface {
function validate(
uint256 previousRoundId,
int256 previousAnswer,
uint256 currentRoundId,
int256 currentAnswer
) external returns (bool);
}
interface LinkTokenInterface {
function allowance(address owner, address spender) external view returns (uint256 remaining);
function approve(address spender, uint256 value) external returns (bool success);
function balanceOf(address owner) external view returns (uint256 balance);
function decimals() external view returns (uint8 decimalPlaces);
function decreaseApproval(address spender, uint256 addedValue) external returns (bool success);
function increaseApproval(address spender, uint256 subtractedValue) external;
function name() external view returns (string memory tokenName);
function symbol() external view returns (string memory tokenSymbol);
function totalSupply() external view returns (uint256 totalTokensIssued);
function transfer(address to, uint256 value) external returns (bool success);
function transferAndCall(address to, uint256 value, bytes calldata data) external returns (bool success);
function transferFrom(address from, address to, uint256 value) external returns (bool success);
}
/**
* @title The Prepaid Aggregator contract
* @notice Handles aggregating data pushed in from off-chain, and unlocks
* payment for oracles as they report. Oracles' submissions are gathered in
* rounds, with each round aggregating the submissions for each oracle into a
* single answer. The latest aggregated answer is exposed as well as historical
* answers and their updated at timestamp.
*/
contract FluxAggregator is AggregatorV2V3Interface, Owned {
using SafeMath for uint256;
using SafeMath128 for uint128;
using SafeMath64 for uint64;
using SafeMath32 for uint32;
struct Round {
int256 answer;
uint64 startedAt;
uint64 updatedAt;
uint32 answeredInRound;
}
struct RoundDetails {
int256[] submissions;
uint32 maxSubmissions;
uint32 minSubmissions;
uint32 timeout;
uint128 paymentAmount;
}
struct OracleStatus {
uint128 withdrawable;
uint32 startingRound;
uint32 endingRound;
uint32 lastReportedRound;
uint32 lastStartedRound;
int256 latestSubmission;
uint16 index;
address admin;
address pendingAdmin;
}
struct Requester {
bool authorized;
uint32 delay;
uint32 lastStartedRound;
}
struct Funds {
uint128 available;
uint128 allocated;
}
LinkTokenInterface public linkToken;
AggregatorValidatorInterface public validator;
// Round related params
uint128 public paymentAmount;
uint32 public maxSubmissionCount;
uint32 public minSubmissionCount;
uint32 public restartDelay;
uint32 public timeout;
uint8 public override decimals;
string public override description;
int256 immutable public minSubmissionValue;
int256 immutable public maxSubmissionValue;
uint256 constant public override version = 3;
/**
* @notice To ensure owner isn't withdrawing required funds as oracles are
* submitting updates, we enforce that the contract maintains a minimum
* reserve of RESERVE_ROUNDS * oracleCount() LINK earmarked for payment to
* oracles. (Of course, this doesn't prevent the contract from running out of
* funds without the owner's intervention.)
*/
uint256 constant private RESERVE_ROUNDS = 2;
uint256 constant private MAX_ORACLE_COUNT = 77;
uint32 constant private ROUND_MAX = 2**32-1;
uint256 private constant VALIDATOR_GAS_LIMIT = 100000;
// An error specific to the Aggregator V3 Interface, to prevent possible
// confusion around accidentally reading unset values as reported values.
string constant private V3_NO_DATA_ERROR = "No data present";
uint32 private reportingRoundId;
uint32 internal latestRoundId;
mapping(address => OracleStatus) private oracles;
mapping(uint32 => Round) internal rounds;
mapping(uint32 => RoundDetails) internal details;
mapping(address => Requester) internal requesters;
address[] private oracleAddresses;
Funds private recordedFunds;
event AvailableFundsUpdated(
uint256 indexed amount
);
event RoundDetailsUpdated(
uint128 indexed paymentAmount,
uint32 indexed minSubmissionCount,
uint32 indexed maxSubmissionCount,
uint32 restartDelay,
uint32 timeout // measured in seconds
);
event OraclePermissionsUpdated(
address indexed oracle,
bool indexed whitelisted
);
event OracleAdminUpdated(
address indexed oracle,
address indexed newAdmin
);
event OracleAdminUpdateRequested(
address indexed oracle,
address admin,
address newAdmin
);
event SubmissionReceived(
int256 indexed submission,
uint32 indexed round,
address indexed oracle
);
event RequesterPermissionsSet(
address indexed requester,
bool authorized,
uint32 delay
);
event ValidatorUpdated(
address indexed previous,
address indexed current
);
/**
* @notice set up the aggregator with initial configuration
* @param _link The address of the LINK token
* @param _paymentAmount The amount paid of LINK paid to each oracle per submission, in wei (units of 10⁻¹⁸ LINK)
* @param _timeout is the number of seconds after the previous round that are
* allowed to lapse before allowing an oracle to skip an unfinished round
* @param _validator is an optional contract address for validating
* external validation of answers
* @param _minSubmissionValue is an immutable check for a lower bound of what
* submission values are accepted from an oracle
* @param _maxSubmissionValue is an immutable check for an upper bound of what
* submission values are accepted from an oracle
* @param _decimals represents the number of decimals to offset the answer by
* @param _description a short description of what is being reported
*/
constructor(
address _link,
uint128 _paymentAmount,
uint32 _timeout,
address _validator,
int256 _minSubmissionValue,
int256 _maxSubmissionValue,
uint8 _decimals,
string memory _description
) public {
linkToken = LinkTokenInterface(_link);
updateFutureRounds(_paymentAmount, 0, 0, 0, _timeout);
setValidator(_validator);
minSubmissionValue = _minSubmissionValue;
maxSubmissionValue = _maxSubmissionValue;
decimals = _decimals;
description = _description;
rounds[0].updatedAt = uint64(block.timestamp.sub(uint256(_timeout)));
}
/**
* @notice called by oracles when they have witnessed a need to update
* @param _roundId is the ID of the round this submission pertains to
* @param _submission is the updated data that the oracle is submitting
*/
function submit(uint256 _roundId, int256 _submission)
external
{
bytes memory error = validateOracleRound(msg.sender, uint32(_roundId));
require(_submission >= minSubmissionValue, "value below minSubmissionValue");
require(_submission <= maxSubmissionValue, "value above maxSubmissionValue");
require(error.length == 0, string(error));
oracleInitializeNewRound(uint32(_roundId));
recordSubmission(_submission, uint32(_roundId));
(bool updated, int256 newAnswer) = updateRoundAnswer(uint32(_roundId));
payOracle(uint32(_roundId));
deleteRoundDetails(uint32(_roundId));
if (updated) {
validateAnswer(uint32(_roundId), newAnswer);
}
}
/**
* @notice called by the owner to remove and add new oracles as well as
* update the round related parameters that pertain to total oracle count
* @param _removed is the list of addresses for the new Oracles being removed
* @param _added is the list of addresses for the new Oracles being added
* @param _addedAdmins is the admin addresses for the new respective _added
* list. Only this address is allowed to access the respective oracle's funds
* @param _minSubmissions is the new minimum submission count for each round
* @param _maxSubmissions is the new maximum submission count for each round
* @param _restartDelay is the number of rounds an Oracle has to wait before
* they can initiate a round
*/
function changeOracles(
address[] calldata _removed,
address[] calldata _added,
address[] calldata _addedAdmins,
uint32 _minSubmissions,
uint32 _maxSubmissions,
uint32 _restartDelay
)
external
onlyOwner()
{
for (uint256 i = 0; i < _removed.length; i++) {
removeOracle(_removed[i]);
}
require(_added.length == _addedAdmins.length, "need same oracle and admin count");
require(uint256(oracleCount()).add(_added.length) <= MAX_ORACLE_COUNT, "max oracles allowed");
for (uint256 i = 0; i < _added.length; i++) {
addOracle(_added[i], _addedAdmins[i]);
}
updateFutureRounds(paymentAmount, _minSubmissions, _maxSubmissions, _restartDelay, timeout);
}
/**
* @notice update the round and payment related parameters for subsequent
* rounds
* @param _paymentAmount is the payment amount for subsequent rounds
* @param _minSubmissions is the new minimum submission count for each round
* @param _maxSubmissions is the new maximum submission count for each round
* @param _restartDelay is the number of rounds an Oracle has to wait before
* they can initiate a round
*/
function updateFutureRounds(
uint128 _paymentAmount,
uint32 _minSubmissions,
uint32 _maxSubmissions,
uint32 _restartDelay,
uint32 _timeout
)
public
onlyOwner()
{
uint32 oracleNum = oracleCount(); // Save on storage reads
require(_maxSubmissions >= _minSubmissions, "max must equal/exceed min");
require(oracleNum >= _maxSubmissions, "max cannot exceed total");
require(oracleNum == 0 || oracleNum > _restartDelay, "delay cannot exceed total");
require(recordedFunds.available >= requiredReserve(_paymentAmount), "insufficient funds for payment");
if (oracleCount() > 0) {
require(_minSubmissions > 0, "min must be greater than 0");
}
paymentAmount = _paymentAmount;
minSubmissionCount = _minSubmissions;
maxSubmissionCount = _maxSubmissions;
restartDelay = _restartDelay;
timeout = _timeout;
emit RoundDetailsUpdated(
paymentAmount,
_minSubmissions,
_maxSubmissions,
_restartDelay,
_timeout
);
}
/**
* @notice the amount of payment yet to be withdrawn by oracles
*/
function allocatedFunds()
external
view
returns (uint128)
{
return recordedFunds.allocated;
}
/**
* @notice the amount of future funding available to oracles
*/
function availableFunds()
external
view
returns (uint128)
{
return recordedFunds.available;
}
/**
* @notice recalculate the amount of LINK available for payouts
*/
function updateAvailableFunds()
public
{
Funds memory funds = recordedFunds;
uint256 nowAvailable = linkToken.balanceOf(address(this)).sub(funds.allocated);
if (funds.available != nowAvailable) {
recordedFunds.available = uint128(nowAvailable);
emit AvailableFundsUpdated(nowAvailable);
}
}
/**
* @notice returns the number of oracles
*/
function oracleCount() public view returns (uint8) {
return uint8(oracleAddresses.length);
}
/**
* @notice returns an array of addresses containing the oracles on contract
*/
function getOracles() external view returns (address[] memory) {
return oracleAddresses;
}
/**
* @notice get the most recently reported answer
*
* @dev #[deprecated] Use latestRoundData instead. This does not error if no
* answer has been reached, it will simply return 0. Either wait to point to
* an already answered Aggregator or use the recommended latestRoundData
* instead which includes better verification information.
*/
function latestAnswer()
public
view
virtual
override
returns (int256)
{
return rounds[latestRoundId].answer;
}
/**
* @notice get the most recent updated at timestamp
*
* @dev #[deprecated] Use latestRoundData instead. This does not error if no
* answer has been reached, it will simply return 0. Either wait to point to
* an already answered Aggregator or use the recommended latestRoundData
* instead which includes better verification information.
*/
function latestTimestamp()
public
view
virtual
override
returns (uint256)
{
return rounds[latestRoundId].updatedAt;
}
/**
* @notice get the ID of the last updated round
*
* @dev #[deprecated] Use latestRoundData instead. This does not error if no
* answer has been reached, it will simply return 0. Either wait to point to
* an already answered Aggregator or use the recommended latestRoundData
* instead which includes better verification information.
*/
function latestRound()
public
view
virtual
override
returns (uint256)
{
return latestRoundId;
}
/**
* @notice get past rounds answers
* @param _roundId the round number to retrieve the answer for
*
* @dev #[deprecated] Use getRoundData instead. This does not error if no
* answer has been reached, it will simply return 0. Either wait to point to
* an already answered Aggregator or use the recommended getRoundData
* instead which includes better verification information.
*/
function getAnswer(uint256 _roundId)
public
view
virtual
override
returns (int256)
{
if (validRoundId(_roundId)) {
return rounds[uint32(_roundId)].answer;
}
return 0;
}
/**
* @notice get timestamp when an answer was last updated
* @param _roundId the round number to retrieve the updated timestamp for
*
* @dev #[deprecated] Use getRoundData instead. This does not error if no
* answer has been reached, it will simply return 0. Either wait to point to
* an already answered Aggregator or use the recommended getRoundData
* instead which includes better verification information.
*/
function getTimestamp(uint256 _roundId)
public
view
virtual
override
returns (uint256)
{
if (validRoundId(_roundId)) {
return rounds[uint32(_roundId)].updatedAt;
}
return 0;
}
/**
* @notice get data about a round. Consumers are encouraged to check
* that they're receiving fresh data by inspecting the updatedAt and
* answeredInRound return values.
* @param _roundId the round ID to retrieve the round data for
* @return roundId is the round ID for which data was retrieved
* @return answer is the answer for the given round
* @return startedAt is the timestamp when the round was started. This is 0
* if the round hasn't been started yet.
* @return updatedAt is the timestamp when the round last was updated (i.e.
* answer was last computed)
* @return answeredInRound is the round ID of the round in which the answer
* was computed. answeredInRound may be smaller than roundId when the round
* timed out. answeredInRound is equal to roundId when the round didn't time out
* and was completed regularly.
* @dev Note that for in-progress rounds (i.e. rounds that haven't yet received
* maxSubmissions) answer and updatedAt may change between queries.
*/
function getRoundData(uint80 _roundId)
public
view
virtual
override
returns (
uint80 roundId,
int256 answer,
uint256 startedAt,
uint256 updatedAt,
uint80 answeredInRound
)
{
Round memory r = rounds[uint32(_roundId)];
require(r.answeredInRound > 0 && validRoundId(_roundId), V3_NO_DATA_ERROR);
return (
_roundId,
r.answer,
r.startedAt,
r.updatedAt,
r.answeredInRound
);
}
/**
* @notice get data about the latest round. Consumers are encouraged to check
* that they're receiving fresh data by inspecting the updatedAt and
* answeredInRound return values. Consumers are encouraged to
* use this more fully featured method over the "legacy" latestRound/
* latestAnswer/latestTimestamp functions. Consumers are encouraged to check
* that they're receiving fresh data by inspecting the updatedAt and
* answeredInRound return values.
* @return roundId is the round ID for which data was retrieved
* @return answer is the answer for the given round
* @return startedAt is the timestamp when the round was started. This is 0
* if the round hasn't been started yet.
* @return updatedAt is the timestamp when the round last was updated (i.e.
* answer was last computed)
* @return answeredInRound is the round ID of the round in which the answer
* was computed. answeredInRound may be smaller than roundId when the round
* timed out. answeredInRound is equal to roundId when the round didn't time
* out and was completed regularly.
* @dev Note that for in-progress rounds (i.e. rounds that haven't yet
* received maxSubmissions) answer and updatedAt may change between queries.
*/
function latestRoundData()
public
view
virtual
override
returns (
uint80 roundId,
int256 answer,
uint256 startedAt,
uint256 updatedAt,
uint80 answeredInRound
)
{
return getRoundData(latestRoundId);
}
/**
* @notice query the available amount of LINK for an oracle to withdraw
*/
function withdrawablePayment(address _oracle)
external
view
returns (uint256)
{
return oracles[_oracle].withdrawable;
}
/**
* @notice transfers the oracle's LINK to another address. Can only be called
* by the oracle's admin.
* @param _oracle is the oracle whose LINK is transferred
* @param _recipient is the address to send the LINK to
* @param _amount is the amount of LINK to send
*/
function withdrawPayment(address _oracle, address _recipient, uint256 _amount)
external
{
require(oracles[_oracle].admin == msg.sender, "only callable by admin");
// Safe to downcast _amount because the total amount of LINK is less than 2^128.
uint128 amount = uint128(_amount);
uint128 available = oracles[_oracle].withdrawable;
require(available >= amount, "insufficient withdrawable funds");
oracles[_oracle].withdrawable = available.sub(amount);
recordedFunds.allocated = recordedFunds.allocated.sub(amount);
assert(linkToken.transfer(_recipient, uint256(amount)));
}
/**
* @notice transfers the owner's LINK to another address
* @param _recipient is the address to send the LINK to
* @param _amount is the amount of LINK to send
*/
function withdrawFunds(address _recipient, uint256 _amount)
external
onlyOwner()
{
uint256 available = uint256(recordedFunds.available);
require(available.sub(requiredReserve(paymentAmount)) >= _amount, "insufficient reserve funds");
require(linkToken.transfer(_recipient, _amount), "token transfer failed");
updateAvailableFunds();
}
/**
* @notice get the admin address of an oracle
* @param _oracle is the address of the oracle whose admin is being queried
*/
function getAdmin(address _oracle)
external
view
returns (address)
{
return oracles[_oracle].admin;
}
/**
* @notice transfer the admin address for an oracle
* @param _oracle is the address of the oracle whose admin is being transferred
* @param _newAdmin is the new admin address
*/
function transferAdmin(address _oracle, address _newAdmin)
external
{
require(oracles[_oracle].admin == msg.sender, "only callable by admin");
oracles[_oracle].pendingAdmin = _newAdmin;
emit OracleAdminUpdateRequested(_oracle, msg.sender, _newAdmin);
}
/**
* @notice accept the admin address transfer for an oracle
* @param _oracle is the address of the oracle whose admin is being transferred
*/
function acceptAdmin(address _oracle)
external
{
require(oracles[_oracle].pendingAdmin == msg.sender, "only callable by pending admin");
oracles[_oracle].pendingAdmin = address(0);
oracles[_oracle].admin = msg.sender;
emit OracleAdminUpdated(_oracle, msg.sender);
}
/**
* @notice allows non-oracles to request a new round
*/
function requestNewRound()
external
returns (uint80)
{
require(requesters[msg.sender].authorized, "not authorized requester");
uint32 current = reportingRoundId;
require(rounds[current].updatedAt > 0 || timedOut(current), "prev round must be supersedable");
uint32 newRoundId = current.add(1);
requesterInitializeNewRound(newRoundId);
return newRoundId;
}
/**
* @notice allows the owner to specify new non-oracles to start new rounds
* @param _requester is the address to set permissions for
* @param _authorized is a boolean specifying whether they can start new rounds or not
* @param _delay is the number of rounds the requester must wait before starting another round
*/
function setRequesterPermissions(address _requester, bool _authorized, uint32 _delay)
external
onlyOwner()
{
if (requesters[_requester].authorized == _authorized) return;
if (_authorized) {
requesters[_requester].authorized = _authorized;
requesters[_requester].delay = _delay;
} else {
delete requesters[_requester];
}
emit RequesterPermissionsSet(_requester, _authorized, _delay);
}
/**
* @notice called through LINK's transferAndCall to update available funds
* in the same transaction as the funds were transferred to the aggregator
* @param _data is mostly ignored. It is checked for length, to be sure
* nothing strange is passed in.
*/
function onTokenTransfer(address, uint256, bytes calldata _data)
external
{
require(_data.length == 0, "transfer doesn't accept calldata");
updateAvailableFunds();
}
/**
* @notice a method to provide all current info oracles need. Intended only
* only to be callable by oracles. Not for use by contracts to read state.
* @param _oracle the address to look up information for.
*/
function oracleRoundState(address _oracle, uint32 _queriedRoundId)
external
view
returns (
bool _eligibleToSubmit,
uint32 _roundId,
int256 _latestSubmission,
uint64 _startedAt,
uint64 _timeout,
uint128 _availableFunds,
uint8 _oracleCount,
uint128 _paymentAmount
)
{
require(msg.sender == tx.origin, "off-chain reading only");
if (_queriedRoundId > 0) {
Round storage round = rounds[_queriedRoundId];
RoundDetails storage details = details[_queriedRoundId];
return (
eligibleForSpecificRound(_oracle, _queriedRoundId),
_queriedRoundId,
oracles[_oracle].latestSubmission,
round.startedAt,
details.timeout,
recordedFunds.available,
oracleCount(),
(round.startedAt > 0 ? details.paymentAmount : paymentAmount)
);
} else {
return oracleRoundStateSuggestRound(_oracle);
}
}
/**
* @notice method to update the address which does external data validation.
* @param _newValidator designates the address of the new validation contract.
*/
function setValidator(address _newValidator)
public
onlyOwner()
{
address previous = address(validator);
if (previous != _newValidator) {
validator = AggregatorValidatorInterface(_newValidator);
emit ValidatorUpdated(previous, _newValidator);
}
}
/**
* Private
*/
function initializeNewRound(uint32 _roundId)
private
{
updateTimedOutRoundInfo(_roundId.sub(1));
reportingRoundId = _roundId;
RoundDetails memory nextDetails = RoundDetails(
new int256[](0),
maxSubmissionCount,
minSubmissionCount,
timeout,
paymentAmount
);
details[_roundId] = nextDetails;
rounds[_roundId].startedAt = uint64(block.timestamp);
emit NewRound(_roundId, msg.sender, rounds[_roundId].startedAt);
}
function oracleInitializeNewRound(uint32 _roundId)
private
{
if (!newRound(_roundId)) return;
uint256 lastStarted = oracles[msg.sender].lastStartedRound; // cache storage reads
if (_roundId <= lastStarted + restartDelay && lastStarted != 0) return;
initializeNewRound(_roundId);
oracles[msg.sender].lastStartedRound = _roundId;
}
function requesterInitializeNewRound(uint32 _roundId)
private
{
if (!newRound(_roundId)) return;
uint256 lastStarted = requesters[msg.sender].lastStartedRound; // cache storage reads
require(_roundId > lastStarted + requesters[msg.sender].delay || lastStarted == 0, "must delay requests");
initializeNewRound(_roundId);
requesters[msg.sender].lastStartedRound = _roundId;
}
function updateTimedOutRoundInfo(uint32 _roundId)
private
{
if (!timedOut(_roundId)) return;
uint32 prevId = _roundId.sub(1);
rounds[_roundId].answer = rounds[prevId].answer;
rounds[_roundId].answeredInRound = rounds[prevId].answeredInRound;
rounds[_roundId].updatedAt = uint64(block.timestamp);
delete details[_roundId];
}
function eligibleForSpecificRound(address _oracle, uint32 _queriedRoundId)
private
view
returns (bool _eligible)
{
if (rounds[_queriedRoundId].startedAt > 0) {
return acceptingSubmissions(_queriedRoundId) && validateOracleRound(_oracle, _queriedRoundId).length == 0;
} else {
return delayed(_oracle, _queriedRoundId) && validateOracleRound(_oracle, _queriedRoundId).length == 0;
}
}
function oracleRoundStateSuggestRound(address _oracle)
private
view
returns (
bool _eligibleToSubmit,
uint32 _roundId,
int256 _latestSubmission,
uint64 _startedAt,
uint64 _timeout,
uint128 _availableFunds,
uint8 _oracleCount,
uint128 _paymentAmount
)
{
Round storage round = rounds[0];
OracleStatus storage oracle = oracles[_oracle];
bool shouldSupersede = oracle.lastReportedRound == reportingRoundId || !acceptingSubmissions(reportingRoundId);
// Instead of nudging oracles to submit to the next round, the inclusion of
// the shouldSupersede bool in the if condition pushes them towards
// submitting in a currently open round.
if (supersedable(reportingRoundId) && shouldSupersede) {
_roundId = reportingRoundId.add(1);
round = rounds[_roundId];
_paymentAmount = paymentAmount;
_eligibleToSubmit = delayed(_oracle, _roundId);
} else {
_roundId = reportingRoundId;
round = rounds[_roundId];
_paymentAmount = details[_roundId].paymentAmount;
_eligibleToSubmit = acceptingSubmissions(_roundId);
}
if (validateOracleRound(_oracle, _roundId).length != 0) {
_eligibleToSubmit = false;
}
return (
_eligibleToSubmit,
_roundId,
oracle.latestSubmission,
round.startedAt,
details[_roundId].timeout,
recordedFunds.available,
oracleCount(),
_paymentAmount
);
}
function updateRoundAnswer(uint32 _roundId)
internal
returns (bool, int256)
{
if (details[_roundId].submissions.length < details[_roundId].minSubmissions) {
return (false, 0);
}
int256 newAnswer = Median.calculateInplace(details[_roundId].submissions);
rounds[_roundId].answer = newAnswer;
rounds[_roundId].updatedAt = uint64(block.timestamp);
rounds[_roundId].answeredInRound = _roundId;
latestRoundId = _roundId;
emit AnswerUpdated(newAnswer, _roundId, now);
return (true, newAnswer);
}
function validateAnswer(
uint32 _roundId,
int256 _newAnswer
)
private
{
AggregatorValidatorInterface av = validator; // cache storage reads
if (address(av) == address(0)) return;
uint32 prevRound = _roundId.sub(1);
uint32 prevAnswerRoundId = rounds[prevRound].answeredInRound;
int256 prevRoundAnswer = rounds[prevRound].answer;
// We do not want the validator to ever prevent reporting, so we limit its
// gas usage and catch any errors that may arise.
try av.validate{gas: VALIDATOR_GAS_LIMIT}(
prevAnswerRoundId,
prevRoundAnswer,
_roundId,
_newAnswer
) {} catch {}
}
function payOracle(uint32 _roundId)
private
{
uint128 payment = details[_roundId].paymentAmount;
Funds memory funds = recordedFunds;
funds.available = funds.available.sub(payment);
funds.allocated = funds.allocated.add(payment);
recordedFunds = funds;
oracles[msg.sender].withdrawable = oracles[msg.sender].withdrawable.add(payment);
emit AvailableFundsUpdated(funds.available);
}
function recordSubmission(int256 _submission, uint32 _roundId)
private
{
require(acceptingSubmissions(_roundId), "round not accepting submissions");
details[_roundId].submissions.push(_submission);
oracles[msg.sender].lastReportedRound = _roundId;
oracles[msg.sender].latestSubmission = _submission;
emit SubmissionReceived(_submission, _roundId, msg.sender);
}
function deleteRoundDetails(uint32 _roundId)
private
{
if (details[_roundId].submissions.length < details[_roundId].maxSubmissions) return;
delete details[_roundId];
}
function timedOut(uint32 _roundId)
private
view
returns (bool)
{
uint64 startedAt = rounds[_roundId].startedAt;
uint32 roundTimeout = details[_roundId].timeout;
return startedAt > 0 && roundTimeout > 0 && startedAt.add(roundTimeout) < block.timestamp;
}
function getStartingRound(address _oracle)
private
view
returns (uint32)
{
uint32 currentRound = reportingRoundId;
if (currentRound != 0 && currentRound == oracles[_oracle].endingRound) {
return currentRound;
}
return currentRound.add(1);
}
function previousAndCurrentUnanswered(uint32 _roundId, uint32 _rrId)
private
view
returns (bool)
{
return _roundId.add(1) == _rrId && rounds[_rrId].updatedAt == 0;
}
function requiredReserve(uint256 payment)
private
view
returns (uint256)
{
return payment.mul(oracleCount()).mul(RESERVE_ROUNDS);
}
function addOracle(
address _oracle,
address _admin
)
private
{
require(!oracleEnabled(_oracle), "oracle already enabled");
require(_admin != address(0), "cannot set admin to 0");
require(oracles[_oracle].admin == address(0) || oracles[_oracle].admin == _admin, "owner cannot overwrite admin");
oracles[_oracle].startingRound = getStartingRound(_oracle);
oracles[_oracle].endingRound = ROUND_MAX;
oracles[_oracle].index = uint16(oracleAddresses.length);
oracleAddresses.push(_oracle);
oracles[_oracle].admin = _admin;
emit OraclePermissionsUpdated(_oracle, true);
emit OracleAdminUpdated(_oracle, _admin);
}
function removeOracle(
address _oracle
)
private
{
require(oracleEnabled(_oracle), "oracle not enabled");
oracles[_oracle].endingRound = reportingRoundId.add(1);
address tail = oracleAddresses[uint256(oracleCount()).sub(1)];
uint16 index = oracles[_oracle].index;
oracles[tail].index = index;
delete oracles[_oracle].index;
oracleAddresses[index] = tail;
oracleAddresses.pop();
emit OraclePermissionsUpdated(_oracle, false);
}
function validateOracleRound(address _oracle, uint32 _roundId)
private
view
returns (bytes memory)
{
// cache storage reads
uint32 startingRound = oracles[_oracle].startingRound;
uint32 rrId = reportingRoundId;
if (startingRound == 0) return "not enabled oracle";
if (startingRound > _roundId) return "not yet enabled oracle";
if (oracles[_oracle].endingRound < _roundId) return "no longer allowed oracle";
if (oracles[_oracle].lastReportedRound >= _roundId) return "cannot report on previous rounds";
if (_roundId != rrId && _roundId != rrId.add(1) && !previousAndCurrentUnanswered(_roundId, rrId)) return "invalid round to report";
if (_roundId != 1 && !supersedable(_roundId.sub(1))) return "previous round not supersedable";
}
function supersedable(uint32 _roundId)
private
view
returns (bool)
{
return rounds[_roundId].updatedAt > 0 || timedOut(_roundId);
}
function oracleEnabled(address _oracle)
private
view
returns (bool)
{
return oracles[_oracle].endingRound == ROUND_MAX;
}
function acceptingSubmissions(uint32 _roundId)
private
view
returns (bool)
{
return details[_roundId].maxSubmissions != 0;
}
function delayed(address _oracle, uint32 _roundId)
private
view
returns (bool)
{
uint256 lastStarted = oracles[_oracle].lastStartedRound;
return _roundId > lastStarted + restartDelay || lastStarted == 0;
}
function newRound(uint32 _roundId)
private
view
returns (bool)
{
return _roundId == reportingRoundId.add(1);
}
function validRoundId(uint256 _roundId)
private
view
returns (bool)
{
return _roundId <= ROUND_MAX;
}
}
interface AccessControllerInterface {
function hasAccess(address user, bytes calldata data) external view returns (bool);
}
/**
* @title SimpleWriteAccessController
* @notice Gives access to accounts explicitly added to an access list by the
* controller's owner.
* @dev does not make any special permissions for externally, see
* SimpleReadAccessController for that.
*/
contract SimpleWriteAccessController is AccessControllerInterface, Owned {
bool public checkEnabled;
mapping(address => bool) internal accessList;
event AddedAccess(address user);
event RemovedAccess(address user);
event CheckAccessEnabled();
event CheckAccessDisabled();
constructor()
public
{
checkEnabled = true;
}
/**
* @notice Returns the access of an address
* @param _user The address to query
*/
function hasAccess(
address _user,
bytes memory
)
public
view
virtual
override
returns (bool)
{
return accessList[_user] || !checkEnabled;
}
/**
* @notice Adds an address to the access list
* @param _user The address to add
*/
function addAccess(address _user)
external
onlyOwner()
{
if (!accessList[_user]) {
accessList[_user] = true;
emit AddedAccess(_user);
}
}
/**
* @notice Removes an address from the access list
* @param _user The address to remove
*/
function removeAccess(address _user)
external
onlyOwner()
{
if (accessList[_user]) {
accessList[_user] = false;
emit RemovedAccess(_user);
}
}
/**
* @notice makes the access check enforced
*/
function enableAccessCheck()
external
onlyOwner()
{
if (!checkEnabled) {
checkEnabled = true;
emit CheckAccessEnabled();
}
}
/**
* @notice makes the access check unenforced
*/
function disableAccessCheck()
external
onlyOwner()
{
if (checkEnabled) {
checkEnabled = false;
emit CheckAccessDisabled();
}
}
/**
* @dev reverts if the caller does not have access
*/
modifier checkAccess() {
require(hasAccess(msg.sender, msg.data), "No access");
_;
}
}
/**
* @title SimpleReadAccessController
* @notice Gives access to:
* - any externally owned account (note that offchain actors can always read
* any contract storage regardless of onchain access control measures, so this
* does not weaken the access control while improving usability)
* - accounts explicitly added to an access list
* @dev SimpleReadAccessController is not suitable for access controlling writes
* since it grants any externally owned account access! See
* SimpleWriteAccessController for that.
*/
contract SimpleReadAccessController is SimpleWriteAccessController {
/**
* @notice Returns the access of an address
* @param _user The address to query
*/
function hasAccess(
address _user,
bytes memory _calldata
)
public
view
virtual
override
returns (bool)
{
return super.hasAccess(_user, _calldata) || _user == tx.origin;
}
}
/**
* @title AccessControlled FluxAggregator contract
* @notice This contract requires addresses to be added to a controller
* in order to read the answers stored in the FluxAggregator contract
*/
contract AccessControlledAggregator is FluxAggregator, SimpleReadAccessController {
/**
* @notice set up the aggregator with initial configuration
* @param _link The address of the LINK token
* @param _paymentAmount The amount paid of LINK paid to each oracle per submission, in wei (units of 10⁻¹⁸ LINK)
* @param _timeout is the number of seconds after the previous round that are
* allowed to lapse before allowing an oracle to skip an unfinished round
* @param _validator is an optional contract address for validating
* external validation of answers
* @param _minSubmissionValue is an immutable check for a lower bound of what
* submission values are accepted from an oracle
* @param _maxSubmissionValue is an immutable check for an upper bound of what
* submission values are accepted from an oracle
* @param _decimals represents the number of decimals to offset the answer by
* @param _description a short description of what is being reported
*/
constructor(
address _link,
uint128 _paymentAmount,
uint32 _timeout,
address _validator,
int256 _minSubmissionValue,
int256 _maxSubmissionValue,
uint8 _decimals,
string memory _description
) public FluxAggregator(
_link,
_paymentAmount,
_timeout,
_validator,
_minSubmissionValue,
_maxSubmissionValue,
_decimals,
_description
){}
/**
* @notice get data about a round. Consumers are encouraged to check
* that they're receiving fresh data by inspecting the updatedAt and
* answeredInRound return values.
* @param _roundId the round ID to retrieve the round data for
* @return roundId is the round ID for which data was retrieved
* @return answer is the answer for the given round
* @return startedAt is the timestamp when the round was started. This is 0
* if the round hasn't been started yet.
* @return updatedAt is the timestamp when the round last was updated (i.e.
* answer was last computed)
* @return answeredInRound is the round ID of the round in which the answer
* was computed. answeredInRound may be smaller than roundId when the round
* timed out. answerInRound is equal to roundId when the round didn't time out
* and was completed regularly.
* @dev overridden funcion to add the checkAccess() modifier
* @dev Note that for in-progress rounds (i.e. rounds that haven't yet
* received maxSubmissions) answer and updatedAt may change between queries.
*/
function getRoundData(uint80 _roundId)
public
view
override
checkAccess()
returns (
uint80 roundId,
int256 answer,
uint256 startedAt,
uint256 updatedAt,
uint80 answeredInRound
)
{
return super.getRoundData(_roundId);
}
/**
* @notice get data about the latest round. Consumers are encouraged to check
* that they're receiving fresh data by inspecting the updatedAt and
* answeredInRound return values. Consumers are encouraged to
* use this more fully featured method over the "legacy" latestAnswer
* functions. Consumers are encouraged to check that they're receiving fresh
* data by inspecting the updatedAt and answeredInRound return values.
* @return roundId is the round ID for which data was retrieved
* @return answer is the answer for the given round
* @return startedAt is the timestamp when the round was started. This is 0
* if the round hasn't been started yet.
* @return updatedAt is the timestamp when the round last was updated (i.e.
* answer was last computed)
* @return answeredInRound is the round ID of the round in which the answer
* was computed. answeredInRound may be smaller than roundId when the round
* timed out. answerInRound is equal to roundId when the round didn't time out
* and was completed regularly.
* @dev overridden funcion to add the checkAccess() modifier
* @dev Note that for in-progress rounds (i.e. rounds that haven't yet
* received maxSubmissions) answer and updatedAt may change between queries.
*/
function latestRoundData()
public
view
override
checkAccess()
returns (
uint80 roundId,
int256 answer,
uint256 startedAt,
uint256 updatedAt,
uint80 answeredInRound
)
{
return super.latestRoundData();
}
/**
* @notice get the most recently reported answer
* @dev overridden funcion to add the checkAccess() modifier
*
* @dev #[deprecated] Use latestRoundData instead. This does not error if no
* answer has been reached, it will simply return 0. Either wait to point to
* an already answered Aggregator or use the recommended latestRoundData
* instead which includes better verification information.
*/
function latestAnswer()
public
view
override
checkAccess()
returns (int256)
{
return super.latestAnswer();
}
/**
* @notice get the most recently reported round ID
* @dev overridden funcion to add the checkAccess() modifier
*
* @dev #[deprecated] Use latestRoundData instead. This does not error if no
* answer has been reached, it will simply return 0. Either wait to point to
* an already answered Aggregator or use the recommended latestRoundData
* instead which includes better verification information.
*/
function latestRound()
public
view
override
checkAccess()
returns (uint256)
{
return super.latestRound();
}
/**
* @notice get the most recent updated at timestamp
* @dev overridden funcion to add the checkAccess() modifier
*
* @dev #[deprecated] Use latestRoundData instead. This does not error if no
* answer has been reached, it will simply return 0. Either wait to point to
* an already answered Aggregator or use the recommended latestRoundData
* instead which includes better verification information.
*/
function latestTimestamp()
public
view
override
checkAccess()
returns (uint256)
{
return super.latestTimestamp();
}
/**
* @notice get past rounds answers
* @dev overridden funcion to add the checkAccess() modifier
* @param _roundId the round number to retrieve the answer for
*
* @dev #[deprecated] Use getRoundData instead. This does not error if no
* answer has been reached, it will simply return 0. Either wait to point to
* an already answered Aggregator or use the recommended getRoundData
* instead which includes better verification information.
*/
function getAnswer(uint256 _roundId)
public
view
override
checkAccess()
returns (int256)
{
return super.getAnswer(_roundId);
}
/**
* @notice get timestamp when an answer was last updated
* @dev overridden funcion to add the checkAccess() modifier
* @param _roundId the round number to retrieve the updated timestamp for
*
* @dev #[deprecated] Use getRoundData instead. This does not error if no
* answer has been reached, it will simply return 0. Either wait to point to
* an already answered Aggregator or use the recommended getRoundData
* instead which includes better verification information.
*/
function getTimestamp(uint256 _roundId)
public
view
override
checkAccess()
returns (uint256)
{
return super.getTimestamp(_roundId);
}
}