⛳ Golf & comments, move tokenAdminRegistry to static config (#1009)

## Motivation
Some minor golfing and adding comments

Main change is moving the token admin registry to the static config in
the onRamp

contracts/gas-snapshots/liquiditymanager.gas-snapshot

@@ -3,9 +3,9 @@ LiquidityManager_addLiquidity:test_addLiquiditySuccess() (gas: 279154)
 LiquidityManager_rebalanceLiquidity:test_InsufficientLiquidityReverts() (gas: 19585)
 LiquidityManager_rebalanceLiquidity:test_InvalidRemoteChainReverts() (gas: 190304)
 LiquidityManager_rebalanceLiquidity:test_rebalanceBetweenPoolsSuccess() (gas: 8809026)
-LiquidityManager_rebalanceLiquidity:test_rebalanceBetweenPoolsSuccess_AlreadyFinalized() (gas: 8757871)
-LiquidityManager_rebalanceLiquidity:test_rebalanceBetweenPools_MultiStageFinalization() (gas: 8753079)
-LiquidityManager_rebalanceLiquidity:test_rebalanceBetweenPools_NativeRewrap() (gas: 8679893)
+LiquidityManager_rebalanceLiquidity:test_rebalanceBetweenPoolsSuccess_AlreadyFinalized() (gas: 8731220)
+LiquidityManager_rebalanceLiquidity:test_rebalanceBetweenPools_MultiStageFinalization() (gas: 8726428)
+LiquidityManager_rebalanceLiquidity:test_rebalanceBetweenPools_NativeRewrap() (gas: 8653242)
 LiquidityManager_rebalanceLiquidity:test_rebalanceLiquiditySuccess() (gas: 379308)
 LiquidityManager_removeLiquidity:test_InsufficientLiquidityReverts() (gas: 184481)
 LiquidityManager_removeLiquidity:test_OnlyOwnerReverts() (gas: 10967)
@@ -16,7 +16,7 @@ LiquidityManager_setCrossChainRebalancer:test_ZeroChainSelectorReverts() (gas: 1
 LiquidityManager_setCrossChainRebalancer:test_setCrossChainRebalancerSuccess() (gas: 162208)
 LiquidityManager_setLocalLiquidityContainer:test_OnlyOwnerReverts() (gas: 11030)
 LiquidityManager_setLocalLiquidityContainer:test_ReverstWhen_CalledWithTheZeroAddress() (gas: 10621)
-LiquidityManager_setLocalLiquidityContainer:test_setLocalLiquidityContainerSuccess() (gas: 3464367)
+LiquidityManager_setLocalLiquidityContainer:test_setLocalLiquidityContainerSuccess() (gas: 3437694)
 LiquidityManager_setMinimumLiquidity:test_OnlyOwnerReverts() (gas: 10925)
 LiquidityManager_setMinimumLiquidity:test_setMinimumLiquiditySuccess() (gas: 36434)
 LiquidityManager_withdrawNative:test_OnlyOwnerReverts() (gas: 13115)

contracts/src/v0.8/ccip/libraries/Internal.sol

@@ -167,11 +167,17 @@ library Internal {
     return _validateEVMAddressFromUint256(abi.decode(encodedAddress, (uint256)));
   }
 
+  /// @dev We disallow the first 1024 addresses to never allow calling precompiles. It is extremely unlikely that
+  /// anyone would ever be able to generate an address in this range.
+  uint256 public constant PRECOMPILE_SPACE = 1024;
+
   /// @notice This method provides a safe way to convert a uint256 to an address.
   /// It will revert if the uint256 is not a valid EVM address, or a precompile address.
   /// @return The address if it is valid, the function will revert otherwise.
   function _validateEVMAddressFromUint256(uint256 encodedAddress) internal pure returns (address) {
-    if (encodedAddress > type(uint160).max || encodedAddress < 10) revert InvalidEVMAddress(abi.encode(encodedAddress));
+    if (encodedAddress > type(uint160).max || encodedAddress < PRECOMPILE_SPACE) {
+      revert InvalidEVMAddress(abi.encode(encodedAddress));
+    }
     return address(uint160(encodedAddress));
   }
 

contracts/src/v0.8/ccip/libraries/RateLimiter.sol

@@ -15,7 +15,7 @@ library RateLimiter {
   error TokenRateLimitReached(uint256 minWaitInSeconds, uint256 available, address tokenAddress);
   error AggregateValueMaxCapacityExceeded(uint256 capacity, uint256 requested);
   error AggregateValueRateLimitReached(uint256 minWaitInSeconds, uint256 available);
-  error InvalidRatelimitRate(Config rateLimiterConfig);
+  error InvalidRateLimitRate(Config rateLimiterConfig);
   error DisabledNonZeroRateLimit(Config config);
   error RateLimitMustBeDisabled();
 
@@ -120,7 +120,7 @@ library RateLimiter {
   function _validateTokenBucketConfig(Config memory config, bool mustBeDisabled) internal pure {
     if (config.isEnabled) {
       if (config.rate >= config.capacity || config.rate == 0) {
-        revert InvalidRatelimitRate(config);
+        revert InvalidRateLimitRate(config);
       }
       if (mustBeDisabled) {
         revert RateLimitMustBeDisabled();

contracts/src/v0.8/ccip/ocr/OCR2Base.sol

@@ -8,7 +8,7 @@ import {OCR2Abstract} from "./OCR2Abstract.sol";
 /// @dev For details on its operation, see the offchain reporting protocol design
 /// doc, which refers to this contract as simply the "contract".
 abstract contract OCR2Base is OwnerIsCreator, OCR2Abstract {
-  error InvalidConfig(string message);
+  error InvalidConfig(InvalidConfigErrorType errorType);
   error WrongMessageLength(uint256 expected, uint256 actual);
   error ConfigDigestMismatch(bytes32 expected, bytes32 actual);
   error ForkedChain(uint256 expected, uint256 actual);
@@ -19,6 +19,14 @@ abstract contract OCR2Base is OwnerIsCreator, OCR2Abstract {
   error NonUniqueSignatures();
   error OracleCannotBeZeroAddress();
 
+  enum InvalidConfigErrorType {
+    F_MUST_BE_POSITIVE,
+    TOO_MANY_SIGNERS,
+    F_TOO_HIGH,
+    REPEATED_ORACLE_ADDRESS,
+    NUM_SIGNERS_NOT_NUM_TRANSMITTERS
+  }
+
   // Packing these fields used on the hot path in a ConfigInfo variable reduces the
   // retrieval of all of them to a minimum number of SLOADs.
   struct ConfigInfo {
@@ -88,10 +96,10 @@ abstract contract OCR2Base is OwnerIsCreator, OCR2Abstract {
 
   // Reverts transaction if config args are invalid
   modifier checkConfigValid(uint256 numSigners, uint256 numTransmitters, uint256 f) {
-    if (numSigners > MAX_NUM_ORACLES) revert InvalidConfig("too many signers");
-    if (f == 0) revert InvalidConfig("f must be positive");
-    if (numSigners != numTransmitters) revert InvalidConfig("oracle addresses out of registration");
-    if (numSigners <= 3 * f) revert InvalidConfig("faulty-oracle f too high");
+    if (numSigners > MAX_NUM_ORACLES) revert InvalidConfig(InvalidConfigErrorType.TOO_MANY_SIGNERS);
+    if (f == 0) revert InvalidConfig(InvalidConfigErrorType.F_MUST_BE_POSITIVE);
+    if (numSigners != numTransmitters) revert InvalidConfig(InvalidConfigErrorType.NUM_SIGNERS_NOT_NUM_TRANSMITTERS);
+    if (numSigners <= 3 * f) revert InvalidConfig(InvalidConfigErrorType.F_TOO_HIGH);
     _;
   }
 
@@ -121,12 +129,14 @@ abstract contract OCR2Base is OwnerIsCreator, OCR2Abstract {
     for (uint256 i = 0; i < newSignersLength; ++i) {
       // add new signer/transmitter addresses
       address signer = signers[i];
-      if (s_oracles[signer].role != Role.Unset) revert InvalidConfig("repeated signer address");
+      if (s_oracles[signer].role != Role.Unset) revert InvalidConfig(InvalidConfigErrorType.REPEATED_ORACLE_ADDRESS);
       if (signer == address(0)) revert OracleCannotBeZeroAddress();
       s_oracles[signer] = Oracle(uint8(i), Role.Signer);
 
       address transmitter = transmitters[i];
-      if (s_oracles[transmitter].role != Role.Unset) revert InvalidConfig("repeated transmitter address");
+      if (s_oracles[transmitter].role != Role.Unset) {
+        revert InvalidConfig(InvalidConfigErrorType.REPEATED_ORACLE_ADDRESS);
+      }
       if (transmitter == address(0)) revert OracleCannotBeZeroAddress();
       s_oracles[transmitter] = Oracle(uint8(i), Role.Transmitter);
     }

contracts/src/v0.8/ccip/offRamp/EVM2EVMOffRamp.sol

@@ -626,7 +626,7 @@ contract EVM2EVMOffRamp is IAny2EVMOffRamp, AggregateRateLimiter, ITypeAndVersio
     // wrap and rethrow the error so we can catch it lower in the stack
     if (!success) revert TokenHandlingError(returnData);
 
-    // If the call was successful, the returnData should be the local token address.
+    // If the call was successful, the returnData should contain only the local token amount.
     if (returnData.length != Pool.CCIP_POOL_V1_RET_BYTES) {
       revert InvalidDataLength(Pool.CCIP_POOL_V1_RET_BYTES, returnData.length);
     }

contracts/src/v0.8/ccip/onRamp/EVM2EVMMultiOnRamp.sol

@@ -47,7 +47,6 @@ contract EVM2EVMMultiOnRamp is IEVM2AnyMultiOnRamp, ILinkAvailable, AggregateRat
   error MustBeCalledByRouter();
   error RouterMustSetOriginalSender();
   error InvalidConfig();
-  error InvalidAddress(bytes encodedAddress);
   error CursedByRMN(uint64 sourceChainSelector);
   error LinkBalanceNotSettled();
   error InvalidNopAddress(address nop);
@@ -81,14 +80,14 @@ contract EVM2EVMMultiOnRamp is IEVM2AnyMultiOnRamp, ILinkAvailable, AggregateRat
     uint64 chainSelector; // ─────╯ Source chainSelector
     uint96 maxNopFeesJuels; // ───╮ Max nop fee balance onramp can have
     address rmnProxy; // ─────────╯ Address of RMN proxy
+    address tokenAdminRegistry; // Token admin registry address
   }
 
   /// @dev Struct to contains the dynamic configuration
   // solhint-disable-next-line gas-struct-packing
   struct DynamicConfig {
     address router; // Router address
     address priceRegistry; // Price registry address
-    address tokenAdminRegistry; // Token admin registry address
   }
 
   /// @dev Struct to hold the fee token configuration for a token, same as the s_premiumMultiplierWeiPerEth but with
@@ -192,6 +191,8 @@ contract EVM2EVMMultiOnRamp is IEVM2AnyMultiOnRamp, ILinkAvailable, AggregateRat
   uint64 internal immutable i_chainSelector;
   /// @dev The address of the rmn proxy
   address internal immutable i_rmnProxy;
+  /// @dev The address of the token admin registry
+  address internal immutable i_tokenAdminRegistry;
   /// @dev the maximum number of nops that can be configured at the same time.
   /// Used to bound gas for loops over nops.
   uint256 private constant MAX_NUMBER_OF_NOPS = 64;
@@ -230,15 +231,18 @@ contract EVM2EVMMultiOnRamp is IEVM2AnyMultiOnRamp, ILinkAvailable, AggregateRat
     TokenTransferFeeConfigArgs[] memory tokenTransferFeeConfigArgs,
     NopAndWeight[] memory nopsAndWeights
   ) AggregateRateLimiter(rateLimiterConfig) {
-    if (staticConfig.linkToken == address(0) || staticConfig.chainSelector == 0 || staticConfig.rmnProxy == address(0))
-    {
+    if (
+      staticConfig.linkToken == address(0) || staticConfig.chainSelector == 0 || staticConfig.rmnProxy == address(0)
+        || staticConfig.tokenAdminRegistry == address(0)
+    ) {
       revert InvalidConfig();
     }
 
     i_linkToken = staticConfig.linkToken;
     i_chainSelector = staticConfig.chainSelector;
     i_maxNopFeesJuels = staticConfig.maxNopFeesJuels;
     i_rmnProxy = staticConfig.rmnProxy;
+    i_tokenAdminRegistry = staticConfig.tokenAdminRegistry;
 
     _setDynamicConfig(dynamicConfig);
     _applyDestChainConfigUpdates(destChainConfigArgs);
@@ -455,7 +459,8 @@ contract EVM2EVMMultiOnRamp is IEVM2AnyMultiOnRamp, ILinkAvailable, AggregateRat
       linkToken: i_linkToken,
       chainSelector: i_chainSelector,
       maxNopFeesJuels: i_maxNopFeesJuels,
-      rmnProxy: i_rmnProxy
+      rmnProxy: i_rmnProxy,
+      tokenAdminRegistry: i_tokenAdminRegistry
     });
   }
 
@@ -483,7 +488,8 @@ contract EVM2EVMMultiOnRamp is IEVM2AnyMultiOnRamp, ILinkAvailable, AggregateRat
         linkToken: i_linkToken,
         chainSelector: i_chainSelector,
         maxNopFeesJuels: i_maxNopFeesJuels,
-        rmnProxy: i_rmnProxy
+        rmnProxy: i_rmnProxy,
+        tokenAdminRegistry: i_tokenAdminRegistry
       }),
       dynamicConfig
     );
@@ -495,7 +501,7 @@ contract EVM2EVMMultiOnRamp is IEVM2AnyMultiOnRamp, ILinkAvailable, AggregateRat
 
   /// @inheritdoc IEVM2AnyOnRampClient
   function getPoolBySourceToken(uint64, /*destChainSelector*/ IERC20 sourceToken) public view returns (IPool) {
-    return IPool(ITokenAdminRegistry(s_dynamicConfig.tokenAdminRegistry).getPool(address(sourceToken)));
+    return IPool(ITokenAdminRegistry(i_tokenAdminRegistry).getPool(address(sourceToken)));
   }
 
   /// @inheritdoc IEVM2AnyOnRampClient

contracts/src/v0.8/ccip/onRamp/EVM2EVMOnRamp.sol

@@ -47,7 +47,6 @@ contract EVM2EVMOnRamp is IEVM2AnyOnRamp, ILinkAvailable, AggregateRateLimiter,
   error MustBeCalledByRouter();
   error RouterMustSetOriginalSender();
   error InvalidConfig();
-  error InvalidAddress(bytes encodedAddress);
   error CursedByRMN();
   error LinkBalanceNotSettled();
   error InvalidNopAddress(address nop);
@@ -78,6 +77,7 @@ contract EVM2EVMOnRamp is IEVM2AnyOnRamp, ILinkAvailable, AggregateRateLimiter,
     uint96 maxNopFeesJuels; // ───╯ Max nop fee balance onramp can have
     address prevOnRamp; //          Address of previous-version OnRamp
     address rmnProxy; //            Address of RMN proxy
+    address tokenAdminRegistry; //  Address of the token admin registry
   }
 
   /// @dev Struct to contains the dynamic configuration
@@ -92,10 +92,9 @@ contract EVM2EVMOnRamp is IEVM2AnyOnRamp, ILinkAvailable, AggregateRateLimiter,
     address priceRegistry; //                    │ Price registry address
     uint32 maxDataBytes; //                      │ Maximum payload data size in bytes
     uint32 maxPerMsgGasLimit; // ────────────────╯ Maximum gas limit for messages targeting EVMs
-    address tokenAdminRegistry; // ──────────────╮ Token admin registry address
     //                                           │
     // The following three properties are defaults, they can be overridden by setting the TokenTransferFeeConfig for a token
-    uint16 defaultTokenFeeUSDCents; //           │ Default token fee charged per token transfer
+    uint16 defaultTokenFeeUSDCents; // ──────────╮ Default token fee charged per token transfer
     uint32 defaultTokenDestGasOverhead; //       │ Default gas charged to execute the token transfer on the destination chain
     //                                           │ Default data availability bytes that are returned from the source pool and sent
     uint32 defaultTokenDestBytesOverhead; //     | to the destination pool. Must be >= Pool.CCIP_LOCK_OR_BURN_V1_RET_BYTES
@@ -174,6 +173,8 @@ contract EVM2EVMOnRamp is IEVM2AnyOnRamp, ILinkAvailable, AggregateRateLimiter,
   address internal immutable i_prevOnRamp;
   /// @dev The address of the RMN proxy
   address internal immutable i_rmnProxy;
+  /// @dev The address of the token admin registry
+  address internal immutable i_tokenAdminRegistry;
   /// @dev the maximum number of nops that can be configured at the same time.
   /// Used to bound gas for loops over nops.
   uint256 private constant MAX_NUMBER_OF_NOPS = 64;
@@ -214,6 +215,7 @@ contract EVM2EVMOnRamp is IEVM2AnyOnRamp, ILinkAvailable, AggregateRateLimiter,
     if (
       staticConfig.linkToken == address(0) || staticConfig.chainSelector == 0 || staticConfig.destChainSelector == 0
         || staticConfig.defaultTxGasLimit == 0 || staticConfig.rmnProxy == address(0)
+        || staticConfig.tokenAdminRegistry == address(0)
     ) revert InvalidConfig();
 
     i_metadataHash = keccak256(
@@ -228,6 +230,7 @@ contract EVM2EVMOnRamp is IEVM2AnyOnRamp, ILinkAvailable, AggregateRateLimiter,
     i_maxNopFeesJuels = staticConfig.maxNopFeesJuels;
     i_prevOnRamp = staticConfig.prevOnRamp;
     i_rmnProxy = staticConfig.rmnProxy;
+    i_tokenAdminRegistry = staticConfig.tokenAdminRegistry;
 
     _setDynamicConfig(dynamicConfig);
     _setFeeTokenConfig(feeTokenConfigs);
@@ -433,7 +436,8 @@ contract EVM2EVMOnRamp is IEVM2AnyOnRamp, ILinkAvailable, AggregateRateLimiter,
       defaultTxGasLimit: i_defaultTxGasLimit,
       maxNopFeesJuels: i_maxNopFeesJuels,
       prevOnRamp: i_prevOnRamp,
-      rmnProxy: i_rmnProxy
+      rmnProxy: i_rmnProxy,
+      tokenAdminRegistry: i_tokenAdminRegistry
     });
   }
 
@@ -467,7 +471,8 @@ contract EVM2EVMOnRamp is IEVM2AnyOnRamp, ILinkAvailable, AggregateRateLimiter,
         defaultTxGasLimit: i_defaultTxGasLimit,
         maxNopFeesJuels: i_maxNopFeesJuels,
         prevOnRamp: i_prevOnRamp,
-        rmnProxy: i_rmnProxy
+        rmnProxy: i_rmnProxy,
+        tokenAdminRegistry: i_tokenAdminRegistry
       }),
       dynamicConfig
     );
@@ -479,7 +484,7 @@ contract EVM2EVMOnRamp is IEVM2AnyOnRamp, ILinkAvailable, AggregateRateLimiter,
 
   /// @inheritdoc IEVM2AnyOnRampClient
   function getPoolBySourceToken(uint64, /*destChainSelector*/ IERC20 sourceToken) public view returns (IPool) {
-    return IPool(ITokenAdminRegistry(s_dynamicConfig.tokenAdminRegistry).getPool(address(sourceToken)));
+    return IPool(ITokenAdminRegistry(i_tokenAdminRegistry).getPool(address(sourceToken)));
   }
 
   /// @inheritdoc IEVM2AnyOnRampClient

contracts/src/v0.8/ccip/pools/BurnFromMintTokenPool.sol

@@ -14,6 +14,7 @@ import {SafeERC20} from "../../vendor/openzeppelin-solidity/v4.8.3/contracts/tok
 /// It either accepts any address as originalSender, or only accepts whitelisted originalSender.
 /// The only way to change whitelisting mode is to deploy a new pool.
 /// If that is expected, please make sure the token's burner/minter roles are adjustable.
+/// @dev This contract is a variant of BurnMintTokenPool that uses `burnFrom(from, amount)`.
 contract BurnFromMintTokenPool is BurnMintTokenPoolAbstract, ITypeAndVersion {
   using SafeERC20 for IBurnMintERC20;
 

contracts/src/v0.8/ccip/pools/BurnMintTokenPool.sol

@@ -12,6 +12,7 @@ import {TokenPool} from "./TokenPool.sol";
 /// It either accepts any address as originalSender, or only accepts whitelisted originalSender.
 /// The only way to change whitelisting mode is to deploy a new pool.
 /// If that is expected, please make sure the token's burner/minter roles are adjustable.
+/// @dev This contract is a variant of BurnMintTokenPool that uses `burn(amount)`.
 contract BurnMintTokenPool is BurnMintTokenPoolAbstract, ITypeAndVersion {
   string public constant override typeAndVersion = "BurnMintTokenPool 1.5.0-dev";
 

contracts/src/v0.8/ccip/pools/BurnWithFromMintTokenPool.sol

@@ -14,6 +14,7 @@ import {SafeERC20} from "../../vendor/openzeppelin-solidity/v4.8.3/contracts/tok
 /// It either accepts any address as originalSender, or only accepts whitelisted originalSender.
 /// The only way to change whitelisting mode is to deploy a new pool.
 /// If that is expected, please make sure the token's burner/minter roles are adjustable.
+/// @dev This contract is a variant of BurnMintTokenPool that uses `burn(from, amount)`.
 contract BurnWithFromMintTokenPool is BurnMintTokenPoolAbstract, ITypeAndVersion {
   using SafeERC20 for IBurnMintERC20;
 

contracts/src/v0.8/ccip/pools/LockReleaseTokenPool.sol

@@ -24,9 +24,6 @@ contract LockReleaseTokenPool is TokenPool, ILiquidityContainer, ITypeAndVersion
 
   string public constant override typeAndVersion = "LockReleaseTokenPool 1.5.0-dev";
 
-  /// @dev The unique lock release pool flag to signal through EIP 165.
-  bytes4 private constant LOCK_RELEASE_INTERFACE_ID = bytes4(keccak256("LockReleaseTokenPool"));
-
   /// @dev Whether or not the pool accepts liquidity.
   /// External liquidity is not required when there is one canonical token deployed to a chain,
   /// and CCIP is facilitating mint/burn on all the other chains, in which case the invariant
@@ -83,15 +80,9 @@ contract LockReleaseTokenPool is TokenPool, ILiquidityContainer, ITypeAndVersion
     return Pool.ReleaseOrMintOutV1({destinationAmount: releaseOrMintIn.amount});
   }
 
-  /// @notice returns the lock release interface flag used for EIP165 identification.
-  function getLockReleaseInterfaceId() public pure returns (bytes4) {
-    return LOCK_RELEASE_INTERFACE_ID;
-  }
-
   // @inheritdoc IERC165
   function supportsInterface(bytes4 interfaceId) public pure virtual override returns (bool) {
-    return interfaceId == LOCK_RELEASE_INTERFACE_ID || interfaceId == type(ILiquidityContainer).interfaceId
-      || super.supportsInterface(interfaceId);
+    return interfaceId == type(ILiquidityContainer).interfaceId || super.supportsInterface(interfaceId);
   }
 
   /// @notice Gets LiquidityManager, can be address(0) if none is configured.