feat: configurable validatorAfkBlocks (#665)

Co-authored-by: Henry <[email protected]>
OffchainLabs · Jun 6, 2024 · 6b42a38 · 6b42a38
1 parent 4926ab5
commit 6b42a38
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Showing 16 changed files with 558 additions and 73 deletions.
diff --git a/contracts/src/rollup/IRollupAdmin.sol b/contracts/src/rollup/IRollupAdmin.sol
@@ -26,6 +26,9 @@ interface IRollupAdmin {
     /// @dev A new minimum assertion period was set
     event MinimumAssertionPeriodSet(uint256 newPeriod);
 
+    /// @dev A new validator afk blocks was set
+    event ValidatorAfkBlocksSet(uint256 newPeriod);
+
     /// @dev New confirm period blocks was set
     event ConfirmPeriodBlocksSet(uint64 newConfirmPeriod);
 
@@ -115,6 +118,17 @@ interface IRollupAdmin {
      */
     function setMinimumAssertionPeriod(uint256 newPeriod) external;
 
+    /**
+     * @notice Set validator afk blocks for the rollup
+     * @param  newAfkBlocks new number of blocks before a validator is considered afk (0 to disable)
+     * @dev    ValidatorAfkBlocks is the number of blocks since the last confirmed 
+     *         assertion (or its first child) before the validator whitelist is removed.
+     *         It's important that this time is greater than the max amount of time it can take to
+     *         to confirm an assertion via the normal method. Therefore we need it to be greater
+     *         than max(2* confirmPeriod, 2 * challengePeriod) with some additional margin.
+     */
+    function setValidatorAfkBlocks(uint64 newAfkBlocks) external;
+
     /**
      * @notice Set number of blocks until a assertion is considered confirmed
      * @param newConfirmPeriod new number of blocks until a assertion is confirmed

diff --git a/contracts/src/rollup/IRollupCore.sol b/contracts/src/rollup/IRollupCore.sol
@@ -47,6 +47,8 @@ interface IRollupCore is IAssertionChain {
 
     function confirmPeriodBlocks() external view returns (uint64);
 
+    function validatorAfkBlocks() external view returns (uint64);
+
     function chainId() external view returns (uint256);
 
     function baseStake() external view returns (uint256);

diff --git a/contracts/src/rollup/RollupAdminLogic.sol b/contracts/src/rollup/RollupAdminLogic.sol
@@ -51,6 +51,10 @@ contract RollupAdminLogic is RollupCore, IRollupAdmin, DoubleLogicUUPSUpgradeabl
         wasmModuleRoot = config.wasmModuleRoot;
         // A little over 15 minutes
         minimumAssertionPeriod = 75;
+        // ValidatorAfkBlocks is defaulted to 28 days assuming a 12 seconds block time. 
+        // Since it can take 14 days under normal circumstances to confirm an assertion, this means 
+        // the validators will have been inactive for a further 14 days before the whitelist is removed.
+        validatorAfkBlocks = 201600;
         challengeGracePeriodBlocks = config.challengeGracePeriodBlocks;
 
         // loser stake is now sent directly to loserStakeEscrow, it must not
@@ -214,6 +218,20 @@ contract RollupAdminLogic is RollupCore, IRollupAdmin, DoubleLogicUUPSUpgradeabl
         // previously: emit OwnerFunctionCalled(8);
     }
 
+    /**
+     * @notice Set validator afk blocks for the rollup
+     * @param  newAfkBlocks new number of blocks before a validator is considered afk (0 to disable)
+     * @dev    ValidatorAfkBlocks is the number of blocks since the last confirmed 
+     *         assertion (or its first child) before the validator whitelist is removed.
+     *         It's important that this time is greater than the max amount of time it can take to
+     *         to confirm an assertion via the normal method. Therefore we need it to be greater
+     *         than max(2* confirmPeriod, 2 * challengePeriod) with some additional margin.
+     */
+    function setValidatorAfkBlocks(uint64 newAfkBlocks) external override {
+        validatorAfkBlocks = newAfkBlocks;
+        emit ValidatorAfkBlocksSet(newAfkBlocks);
+    }
+
     /**
      * @notice Set number of blocks until a assertion is considered confirmed
      * @param newConfirmPeriod new number of blocks

diff --git a/contracts/src/rollup/RollupCore.sol b/contracts/src/rollup/RollupCore.sol
@@ -31,6 +31,8 @@ abstract contract RollupCore is IRollupCore, PausableUpgradeable {
     // These 4 config should be stored into the prev and not used directly
     // An assertion can be confirmed after confirmPeriodBlocks when it is unchallenged
     uint64 public confirmPeriodBlocks;
+    // The validator whitelist can be dropped permissionlessly once the last confirmed assertion or its first child is at least validatorAfkBlocks old
+    uint64 public validatorAfkBlocks;
 
     // ------------------------------
     // STAKING

diff --git a/contracts/src/rollup/RollupUserLogic.sol b/contracts/src/rollup/RollupUserLogic.sol
@@ -35,29 +35,17 @@ contract RollupUserLogic is RollupCore, UUPSNotUpgradeable, IRollupUser {
         return deployTimeChainId != block.chainid;
     }
 
-    /**
-     * @notice Number of blocks since the last confirmed assertion before the validator whitelist is removed
-     *         This is 28 days assuming a 12 seconds block time. Since it can take 14 days under normal
-     *         circumstances to confirm an assertion, this means that validators will have been inactive for
-     *         a further 14 days before the validator whitelist is removed.
-     *
-     *         It's important that this time is greater than the max amount of time it can take to
-     *         to confirm an assertion via the normal method. Therefore we need it to be greater
-     *         than max(2* confirmPeriod, 2 * challengePeriod). With some additional margin
-     *         It's expected that initially confirm and challenge periods are set to 1 week, so 4 weeks
-     *         should give a two weeks of margin before the validators are considered afk.
-     */
-    uint256 public constant VALIDATOR_AFK_BLOCKS = 201600;
-
     function _validatorIsAfk() internal view returns (bool) {
         AssertionNode memory latestConfirmedAssertion = getAssertionStorage(latestConfirmed());
+        uint256 _validatorAfkBlocks = validatorAfkBlocks; // cache and cast to uint256 to prevent overflow
+        if (_validatorAfkBlocks == 0) return false;
         if (latestConfirmedAssertion.createdAtBlock == 0) return false;
         // We consider the validator is gone if the last known assertion is older than VALIDATOR_AFK_BLOCKS
         // Which is either the latest confirmed assertion or the first child of the latest confirmed assertion
         if (latestConfirmedAssertion.firstChildBlock > 0) {
-            return latestConfirmedAssertion.firstChildBlock + VALIDATOR_AFK_BLOCKS < block.number;
+            return latestConfirmedAssertion.firstChildBlock + _validatorAfkBlocks < block.number;
         }
-        return latestConfirmedAssertion.createdAtBlock + VALIDATOR_AFK_BLOCKS < block.number;
+        return latestConfirmedAssertion.createdAtBlock + _validatorAfkBlocks < block.number;
     }
 
     function removeWhitelistAfterFork() external {

diff --git a/contracts/test/Rollup.t.sol b/contracts/test/Rollup.t.sol
@@ -894,7 +894,28 @@ contract RollupTest is Test {
 
     function testSuccessRemoveWhitelistAfterValidatorAfk() public {
         (bytes32 assertionHash,,) = testSuccessConfirmUnchallengedAssertions();
-        vm.roll(userRollup.getAssertion(assertionHash).createdAtBlock + userRollup.VALIDATOR_AFK_BLOCKS() + 1);
+        vm.roll(userRollup.getAssertion(assertionHash).createdAtBlock + userRollup.validatorAfkBlocks() + 1);
+        userRollup.removeWhitelistAfterValidatorAfk();
+    }
+
+    function testSuccessSetValidatorAfk(uint32 x) public {
+        vm.assume(x > 0);
+        (bytes32 assertionHash,,) = testSuccessConfirmUnchallengedAssertions();
+        vm.prank(upgradeExecutorAddr);
+        adminRollup.setValidatorAfkBlocks(x);
+        vm.roll(userRollup.getAssertion(assertionHash).createdAtBlock + x);
+        vm.expectRevert("VALIDATOR_NOT_AFK");
+        userRollup.removeWhitelistAfterValidatorAfk();
+        vm.roll(block.number + 1);
+        userRollup.removeWhitelistAfterValidatorAfk();
+    }
+
+    function testSuccessValidatorAfkDisable() public {
+        (bytes32 assertionHash,,) = testSuccessConfirmUnchallengedAssertions();
+        vm.prank(upgradeExecutorAddr);
+        adminRollup.setValidatorAfkBlocks(0); // set 0 to disable
+        vm.roll(userRollup.getAssertion(assertionHash).createdAtBlock + 1);
+        vm.expectRevert("VALIDATOR_NOT_AFK");
         userRollup.removeWhitelistAfterValidatorAfk();
     }
 

diff --git a/contracts/test/signatures/RollupAdminLogic b/contracts/test/signatures/RollupAdminLogic
@@ -50,6 +50,7 @@
   "setOwner(address)": "13af4035",
   "setSequencerInbox(address)": "4f61f850",
   "setValidator(address[],bool[])": "a3ffb772",
+  "setValidatorAfkBlocks(uint64)": "f112cea3",
   "setValidatorWhitelistDisabled(bool)": "a2b4f1d8",
   "setWasmModuleRoot(bytes32)": "89384960",
   "stakeToken()": "51ed6a30",
@@ -61,6 +62,7 @@
   "upgradeToAndCall(address,bytes)": "4f1ef286",
   "validateAssertionHash(bytes32,((bytes32[2],uint64[2]),uint8,bytes32),bytes32,bytes32)": "e51019a6",
   "validateConfig(bytes32,(bytes32,uint256,address,uint64,uint64))": "04972af9",
+  "validatorAfkBlocks()": "e6b3082c",
   "validatorWalletCreator()": "bc45e0ae",
   "validatorWhitelistDisabled()": "12ab3d3b",
   "wasmModuleRoot()": "8ee1a126",

diff --git a/contracts/test/signatures/RollupCore b/contracts/test/signatures/RollupCore
@@ -35,6 +35,7 @@
   "totalWithdrawableFunds()": "71ef232c",
   "validateAssertionHash(bytes32,((bytes32[2],uint64[2]),uint8,bytes32),bytes32,bytes32)": "e51019a6",
   "validateConfig(bytes32,(bytes32,uint256,address,uint64,uint64))": "04972af9",
+  "validatorAfkBlocks()": "e6b3082c",
   "validatorWalletCreator()": "bc45e0ae",
   "validatorWhitelistDisabled()": "12ab3d3b",
   "wasmModuleRoot()": "8ee1a126",

diff --git a/contracts/test/signatures/RollupUserLogic b/contracts/test/signatures/RollupUserLogic
@@ -1,5 +1,4 @@
 {
-  "VALIDATOR_AFK_BLOCKS()": "4ceccfe5",
   "_stakerMap(address)": "e8bd4922",
   "addToDeposit(address,address,uint256)": "685f5ecc",
   "amountStaked(address)": "ef40a670",
@@ -53,6 +52,7 @@
   "totalWithdrawableFunds()": "71ef232c",
   "validateAssertionHash(bytes32,((bytes32[2],uint64[2]),uint8,bytes32),bytes32,bytes32)": "e51019a6",
   "validateConfig(bytes32,(bytes32,uint256,address,uint64,uint64))": "04972af9",
+  "validatorAfkBlocks()": "e6b3082c",
   "validatorWalletCreator()": "bc45e0ae",
   "validatorWhitelistDisabled()": "12ab3d3b",
   "wasmModuleRoot()": "8ee1a126",

diff --git a/contracts/test/storage/RollupAdminLogic b/contracts/test/storage/RollupAdminLogic
@@ -7,6 +7,7 @@
 | __gap                          | uint256[49]                                   | 52   | 0      | 1568  | src/rollup/RollupAdminLogic.sol:RollupAdminLogic |
 | chainId                        | uint256                                       | 101  | 0      | 32    | src/rollup/RollupAdminLogic.sol:RollupAdminLogic |
 | confirmPeriodBlocks            | uint64                                        | 102  | 0      | 8     | src/rollup/RollupAdminLogic.sol:RollupAdminLogic |
+| validatorAfkBlocks             | uint64                                        | 102  | 8      | 8     | src/rollup/RollupAdminLogic.sol:RollupAdminLogic |
 | baseStake                      | uint256                                       | 103  | 0      | 32    | src/rollup/RollupAdminLogic.sol:RollupAdminLogic |
 | wasmModuleRoot                 | bytes32                                       | 104  | 0      | 32    | src/rollup/RollupAdminLogic.sol:RollupAdminLogic |
 | challengeManager               | contract IEdgeChallengeManager                | 105  | 0      | 20    | src/rollup/RollupAdminLogic.sol:RollupAdminLogic |

diff --git a/contracts/test/storage/RollupCore b/contracts/test/storage/RollupCore
@@ -7,6 +7,7 @@
 | __gap                          | uint256[49]                                   | 52   | 0      | 1568  | src/rollup/RollupCore.sol:RollupCore |
 | chainId                        | uint256                                       | 101  | 0      | 32    | src/rollup/RollupCore.sol:RollupCore |
 | confirmPeriodBlocks            | uint64                                        | 102  | 0      | 8     | src/rollup/RollupCore.sol:RollupCore |
+| validatorAfkBlocks             | uint64                                        | 102  | 8      | 8     | src/rollup/RollupCore.sol:RollupCore |
 | baseStake                      | uint256                                       | 103  | 0      | 32    | src/rollup/RollupCore.sol:RollupCore |
 | wasmModuleRoot                 | bytes32                                       | 104  | 0      | 32    | src/rollup/RollupCore.sol:RollupCore |
 | challengeManager               | contract IEdgeChallengeManager                | 105  | 0      | 20    | src/rollup/RollupCore.sol:RollupCore |

diff --git a/contracts/test/storage/RollupUserLogic b/contracts/test/storage/RollupUserLogic
@@ -7,6 +7,7 @@
 | __gap                          | uint256[49]                                   | 52   | 0      | 1568  | src/rollup/RollupUserLogic.sol:RollupUserLogic |
 | chainId                        | uint256                                       | 101  | 0      | 32    | src/rollup/RollupUserLogic.sol:RollupUserLogic |
 | confirmPeriodBlocks            | uint64                                        | 102  | 0      | 8     | src/rollup/RollupUserLogic.sol:RollupUserLogic |
+| validatorAfkBlocks             | uint64                                        | 102  | 8      | 8     | src/rollup/RollupUserLogic.sol:RollupUserLogic |
 | baseStake                      | uint256                                       | 103  | 0      | 32    | src/rollup/RollupUserLogic.sol:RollupUserLogic |
 | wasmModuleRoot                 | bytes32                                       | 104  | 0      | 32    | src/rollup/RollupUserLogic.sol:RollupUserLogic |
 | challengeManager               | contract IEdgeChallengeManager                | 105  | 0      | 20    | src/rollup/RollupUserLogic.sol:RollupUserLogic |