make gas fee staleness threshold configurable per chain

contracts/src/v0.8/ccip/FeeQuoter.sol

@@ -76,7 +76,8 @@ contract FeeQuoter is AuthorizedCallers, IFeeQuoter, ITypeAndVersion, IReceiver,
   struct StaticConfig {
     uint96 maxFeeJuelsPerMsg; // ─╮ Maximum fee that can be charged for a message
     address linkToken; // ────────╯ LINK token address
-    uint32 stalenessThreshold; // The amount of time a gas price can be stale before it is considered invalid.
+    // The amount of time a token price can be stale before it is considered invalid (gas price staleness is configured per dest chain)
+    uint32 stalenessThreshold;
   }
 
   /// @dev The struct representing the received CCIP feed report from keystone IReceiver.onReport()
@@ -103,6 +104,7 @@ contract FeeQuoter is AuthorizedCallers, IFeeQuoter, ITypeAndVersion, IReceiver,
     uint32 defaultTxGasLimit; //─────────────────╮ Default gas limit for a tx
     uint64 gasMultiplierWeiPerEth; //            │ Multiplier for gas costs, 1e18 based so 11e17 = 10% extra cost.
     uint32 networkFeeUSDCents; //                │ Flat network fee to charge for messages, multiples of 0.01 USD
+    uint32 gasPriceStalenessThreshold; //        │ The amount of time a gas price can be stale before it is considered invalid (0 means disabled)
     bool enforceOutOfOrder; //                   │ Whether to enforce the allowOutOfOrderExecution extraArg value to be true.
     bytes4 chainFamilySelector; // ──────────────╯ Selector that identifies the destination chain's family. Used to determine the correct validations to perform for the dest chain.
   }
@@ -202,7 +204,7 @@ contract FeeQuoter is AuthorizedCallers, IFeeQuoter, ITypeAndVersion, IReceiver,
 
   /// @dev Subset of tokens which prices tracked by this registry which are fee tokens.
   EnumerableSet.AddressSet private s_feeTokens;
-  /// @dev The amount of time a gas price can be stale before it is considered invalid.
+  /// @dev The amount of time a token price can be stale before it is considered invalid.
   uint32 private immutable i_stalenessThreshold;
 
   constructor(
@@ -306,13 +308,7 @@ contract FeeQuoter is AuthorizedCallers, IFeeQuoter, ITypeAndVersion, IReceiver,
     address token,
     uint64 destChainSelector
   ) public view returns (uint224 tokenPrice, uint224 gasPriceValue) {
-    Internal.TimestampedPackedUint224 memory gasPrice = s_usdPerUnitGasByDestChainSelector[destChainSelector];
-    // We do allow a gas price of 0, but no stale or unset gas prices
-    if (gasPrice.timestamp == 0) revert ChainNotSupported(destChainSelector);
-    uint256 timePassed = block.timestamp - gasPrice.timestamp;
-    if (timePassed > i_stalenessThreshold) revert StaleGasPrice(destChainSelector, i_stalenessThreshold, timePassed);
-
-    return (_getValidatedTokenPrice(token), gasPrice.value);
+    return _getTokenAndGasPrices(token, destChainSelector, s_destChainConfigs[destChainSelector]);
   }
 
   /// @notice Convert a given token amount to target token amount.
@@ -374,6 +370,31 @@ contract FeeQuoter is AuthorizedCallers, IFeeQuoter, ITypeAndVersion, IReceiver,
     return Internal.TimestampedPackedUint224({value: rebasedValue, timestamp: uint32(block.timestamp)});
   }
 
+  /// @notice Gets the fee token price and the gas price, both denominated in dollars.
+  /// @param token The source token to get the price for.
+  /// @param destChainSelector The destination chain to get the gas price for.
+  /// @param destChainConfig The config struct for the dest chain selector.
+  /// @return tokenPrice The price of the feeToken in 1e18 dollars per base unit.
+  /// @return gasPriceValue The price of gas in 1e18 dollars per base unit.
+  function _getTokenAndGasPrices(
+    address token,
+    uint64 destChainSelector,
+    DestChainConfig memory destChainConfig
+  ) private view returns (uint224 tokenPrice, uint224 gasPriceValue) {
+    if (!destChainConfig.isEnabled) revert ChainNotSupported(destChainSelector);
+    Internal.TimestampedPackedUint224 memory gasPrice = s_usdPerUnitGasByDestChainSelector[destChainSelector];
+    // If the staleness threshold is 0, we consider the gas price to be always valid
+    if (destChainConfig.gasPriceStalenessThreshold != 0) {
+      // We do allow a gas price of 0, but no stale or unset gas prices
+      uint256 timePassed = block.timestamp - gasPrice.timestamp;
+      if (timePassed > destChainConfig.gasPriceStalenessThreshold) {
+        revert StaleGasPrice(destChainSelector, destChainConfig.gasPriceStalenessThreshold, timePassed);
+      }
+    }
+
+    return (_getValidatedTokenPrice(token), gasPrice.value);
+  }
+
   // ================================================================
   // │                         Fee tokens                           │
   // ================================================================
@@ -507,7 +528,8 @@ contract FeeQuoter is AuthorizedCallers, IFeeQuoter, ITypeAndVersion, IReceiver,
     _validateMessage(destChainConfig, message.data.length, numberOfTokens, message.receiver);
 
     // The below call asserts that feeToken is a supported token
-    (uint224 feeTokenPrice, uint224 packedGasPrice) = getTokenAndGasPrices(message.feeToken, destChainSelector);
+    (uint224 feeTokenPrice, uint224 packedGasPrice) =
+      _getTokenAndGasPrices(message.feeToken, destChainSelector, destChainConfig);
 
     // Calculate premiumFee in USD with 18 decimals precision first.
     // If message-only and no token transfers, a flat network fee is charged.

contracts/src/v0.8/ccip/test/feeQuoter/FeeQuoter.t.sol

@@ -1,8 +1,6 @@
 // SPDX-License-Identifier: BUSL-1.1
 pragma solidity 0.8.24;
 
-import {IFeeQuoter} from "../../interfaces/IFeeQuoter.sol";
-
 import {KeystoneFeedsPermissionHandler} from "../../../keystone/KeystoneFeedsPermissionHandler.sol";
 import {AuthorizedCallers} from "../../../shared/access/AuthorizedCallers.sol";
 import {MockV3Aggregator} from "../../../tests/MockV3Aggregator.sol";
@@ -598,16 +596,15 @@ contract FeeQuoter_getTokenAndGasPrices is FeeQuoterSetup {
 
   function test_ZeroGasPrice_Success() public {
     uint64 zeroGasDestChainSelector = 345678;
-    Internal.GasPriceUpdate[] memory gasPriceUpdates = new Internal.GasPriceUpdate[](1);
-    gasPriceUpdates[0] = Internal.GasPriceUpdate({destChainSelector: zeroGasDestChainSelector, usdPerUnitGas: 0});
+    FeeQuoter.DestChainConfigArgs[] memory destChainConfigArgs = _generateFeeQuoterDestChainConfigArgs();
+    destChainConfigArgs[0].destChainSelector = zeroGasDestChainSelector;
+    destChainConfigArgs[0].destChainConfig.gasPriceStalenessThreshold = 0;
 
-    Internal.PriceUpdates memory priceUpdates =
-      Internal.PriceUpdates({tokenPriceUpdates: new Internal.TokenPriceUpdate[](0), gasPriceUpdates: gasPriceUpdates});
-    s_feeQuoter.updatePrices(priceUpdates);
+    s_feeQuoter.applyDestChainConfigUpdates(destChainConfigArgs);
 
     (, uint224 gasPrice) = s_feeQuoter.getTokenAndGasPrices(s_sourceFeeToken, zeroGasDestChainSelector);
 
-    assertEq(gasPrice, priceUpdates.gasPriceUpdates[0].usdPerUnitGas);
+    assertEq(gasPrice, 0);
   }
 
   function test_UnsupportedChain_Revert() public {

contracts/src/v0.8/ccip/test/feeQuoter/FeeQuoterSetup.t.sol

@@ -254,6 +254,7 @@ contract FeeQuoterSetup is TokenSetup {
         defaultTxGasLimit: GAS_LIMIT,
         gasMultiplierWeiPerEth: 5e17,
         networkFeeUSDCents: 1_00,
+        gasPriceStalenessThreshold: uint32(TWELVE_HOURS),
         enforceOutOfOrder: false,
         chainFamilySelector: Internal.CHAIN_FAMILY_SELECTOR_EVM
       })