Remove missing proof leniency (#210)

Author: 2-towns

configuration/configuration.js

@@ -6,24 +6,23 @@ const DEFAULT_CONFIGURATION = {
   collateral: {
     repairRewardPercentage: 10,
     maxNumberOfSlashes: 2,
-    slashCriterion: 2,
     slashPercentage: 20,
   },
   proofs: {
     // period has to be less than downtime * blocktime
     period: 120, // seconds
     timeout: 30, // seconds
     downtime: 64, // number of blocks
-    downtimeProduct: 67 // number of blocks
+    downtimeProduct: 67, // number of blocks
   },
   reservations: {
-    maxReservations: 3
-  }
+    maxReservations: 3,
+  },
 }
 
 function loadConfiguration(name) {
   const path = `${BASE_PATH}/${name}/configuration.js`
-  if(fs.existsSync(path)) {
+  if (fs.existsSync(path)) {
     return require(path)
   } else {
     return DEFAULT_CONFIGURATION

configuration/networks/hardhat/configuration.js

@@ -2,7 +2,6 @@ module.exports = {
   collateral: {
     repairRewardPercentage: 10,
     maxNumberOfSlashes: 2,
-    slashCriterion: 2,
     slashPercentage: 20,
   },
   proofs: {
@@ -11,9 +10,9 @@ module.exports = {
     period: 90, // seconds
     timeout: 30, // seconds
     downtime: 96, // number of blocks
-    downtimeProduct: 97 // number of blocks
+    downtimeProduct: 97, // number of blocks
   },
   reservations: {
-    maxReservations: 3
-  }
+    maxReservations: 3,
+  },
 }

contracts/Configuration.sol

@@ -13,7 +13,6 @@ struct CollateralConfig {
   /// @dev percentage of collateral that is used as repair reward
   uint8 repairRewardPercentage;
   uint8 maxNumberOfSlashes; // frees slot when the number of slashing reaches this value
-  uint16 slashCriterion; // amount of proofs missed that lead to slashing
   uint8 slashPercentage; // percentage of the collateral that is slashed
 }
 

contracts/FuzzMarketplace.sol

@@ -9,7 +9,7 @@ contract FuzzMarketplace is Marketplace {
   constructor()
     Marketplace(
       MarketplaceConfig(
-        CollateralConfig(10, 5, 3, 10),
+        CollateralConfig(10, 5, 10),
         ProofConfig(10, 5, 64, "", 67),
         SlotReservationsConfig(20)
       ),

contracts/Marketplace.sol

@@ -336,18 +336,13 @@ contract Marketplace is SlotReservations, Proofs, StateRetrieval, Endian {
 
     // TODO: Reward for validator that calls this function
 
-    if (missingProofs(slotId) % _config.collateral.slashCriterion == 0) {
-      uint256 slashedAmount = (request.ask.collateralPerSlot() *
-        _config.collateral.slashPercentage) / 100;
-      slot.currentCollateral -= slashedAmount;
-      if (
-        missingProofs(slotId) / _config.collateral.slashCriterion >=
-        _config.collateral.maxNumberOfSlashes
-      ) {
-        // When the number of slashings is at or above the allowed amount,
-        // free the slot.
-        _forciblyFreeSlot(slotId);
-      }
+    uint256 slashedAmount = (request.ask.collateralPerSlot() *
+      _config.collateral.slashPercentage) / 100;
+    slot.currentCollateral -= slashedAmount;
+    if (missingProofs(slotId) >= _config.collateral.maxNumberOfSlashes) {
+      // When the number of slashings is at or above the allowed amount,
+      // free the slot.
+      _forciblyFreeSlot(slotId);
     }
   }
 

test/Marketplace.test.js

@@ -1362,17 +1362,17 @@ describe("Marketplace", function () {
     })
 
     describe("slashing when missing proofs", function () {
-      it("reduces collateral when too many proofs are missing", async function () {
+      it("reduces collateral when a proof is missing", async function () {
         const id = slotId(slot)
-        const { slashCriterion, slashPercentage } = config.collateral
+        const { slashPercentage } = config.collateral
         await marketplace.reserveSlot(slot.request, slot.index)
         await marketplace.fillSlot(slot.request, slot.index, proof)
-        for (let i = 0; i < slashCriterion; i++) {
-          await waitUntilProofIsRequired(id)
-          let missedPeriod = periodOf(await currentTime())
-          await advanceTimeForNextBlock(period + 1)
-          await marketplace.markProofAsMissing(id, missedPeriod)
-        }
+
+        await waitUntilProofIsRequired(id)
+        let missedPeriod = periodOf(await currentTime())
+        await advanceTimeForNextBlock(period + 1)
+        await marketplace.markProofAsMissing(id, missedPeriod)
+
         const collateral = collateralPerSlot(request)
         const expectedBalance = Math.round(
           (collateral * (100 - slashPercentage)) / 100

test/examples.js

@@ -6,7 +6,6 @@ const exampleConfiguration = () => ({
   collateral: {
     repairRewardPercentage: 10,
     maxNumberOfSlashes: 5,
-    slashCriterion: 3,
     slashPercentage: 10,
   },
   proofs: {