chore: Separate config vars for prune penalties (#16694)

We were using the same config variable for the slash penalty for a
pruned epoch where the data was and was not made available. This commit
adds a new env var so we can set different values for each.

Please read [contributing guidelines](CONTRIBUTING.md) and remove this
line.

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template](?expand=1&template=audit.md).

Author: spalladino

yarn-project/aztec-node/src/aztec-node/server.ts

@@ -328,14 +328,14 @@ export class AztecNodeService implements AztecNode, AztecNodeAdmin, Traceable {
     }
 
     let epochPruneWatcher: EpochPruneWatcher | undefined;
-    if (config.slashPrunePenalty > 0n) {
+    if (config.slashPrunePenalty > 0n || config.slashDataWithholdingPenalty > 0n) {
       epochPruneWatcher = new EpochPruneWatcher(
         archiver,
         archiver,
         epochCache,
         p2pClient.getTxProvider(),
         blockBuilder,
-        config.slashPrunePenalty,
+        config,
       );
       await epochPruneWatcher.start();
       watchers.push(epochPruneWatcher);

yarn-project/aztec/src/cli/chain_l2_config.ts

@@ -77,6 +77,7 @@ export const testnetIgnitionL2ChainConfig: L2ChainConfig = {
   slashInactivityTargetPercentage: 0,
   slashInactivityPenalty: 0n,
   slashPrunePenalty: 0n,
+  slashDataWithholdingPenalty: 0n,
   slashProposeInvalidAttestationsPenalty: 0n,
   slashAttestDescendantOfInvalidPenalty: 0n,
   slashBroadcastedInvalidBlockPenalty: 0n,
@@ -153,6 +154,7 @@ export const alphaTestnetL2ChainConfig: L2ChainConfig = {
   slashInactivityTargetPercentage: 0.7,
   slashInactivityPenalty: DefaultL1ContractsConfig.slashAmountSmall,
   slashPrunePenalty: DefaultL1ContractsConfig.slashAmountSmall,
+  slashDataWithholdingPenalty: DefaultL1ContractsConfig.slashAmountSmall,
   slashProposeInvalidAttestationsPenalty: DefaultL1ContractsConfig.slashAmountLarge,
   slashAttestDescendantOfInvalidPenalty: DefaultL1ContractsConfig.slashAmountLarge,
   slashUnknownPenalty: DefaultL1ContractsConfig.slashAmountSmall,
@@ -322,6 +324,7 @@ export async function enrichEnvironmentWithChainConfig(networkName: NetworkNames
   enrichVar('SLASH_MIN_PENALTY_PERCENTAGE', config.slashMinPenaltyPercentage.toString());
   enrichVar('SLASH_MAX_PENALTY_PERCENTAGE', config.slashMaxPenaltyPercentage.toString());
   enrichVar('SLASH_PRUNE_PENALTY', config.slashPrunePenalty.toString());
+  enrichVar('SLASH_DATA_WITHHOLDING_PENALTY', config.slashDataWithholdingPenalty.toString());
   enrichVar('SLASH_INACTIVITY_TARGET_PERCENTAGE', config.slashInactivityTargetPercentage.toString());
   enrichVar('SLASH_INACTIVITY_PENALTY', config.slashInactivityPenalty.toString());
   enrichVar('SLASH_PROPOSE_INVALID_ATTESTATIONS_PENALTY', config.slashProposeInvalidAttestationsPenalty.toString());

yarn-project/end-to-end/src/e2e_p2p/data_withholding_slash.test.ts

@@ -103,6 +103,7 @@ describe('e2e_p2p_data_withholding_slash', () => {
     const slashingAmount = slashingUnit * 3n;
     expect(activationThreshold - slashingAmount).toBeLessThan(ejectionThreshold);
 
+    t.ctx.aztecNodeConfig.slashDataWithholdingPenalty = slashingAmount;
     t.ctx.aztecNodeConfig.slashPrunePenalty = slashingAmount;
     t.ctx.aztecNodeConfig.validatorReexecute = false;
     t.ctx.aztecNodeConfig.minTxsPerBlock = 1;

yarn-project/foundation/src/config/env_var.ts

@@ -204,6 +204,7 @@ export type EnvVar =
   | 'SLASH_VALIDATORS_ALWAYS'
   | 'SLASH_VALIDATORS_NEVER'
   | 'SLASH_PRUNE_PENALTY'
+  | 'SLASH_DATA_WITHHOLDING_PENALTY'
   | 'SLASH_INACTIVITY_PENALTY'
   | 'SLASH_INACTIVITY_TARGET_PERCENTAGE'
   | 'SLASH_INVALID_BLOCK_PENALTY'

yarn-project/slasher/src/config.ts

@@ -18,6 +18,7 @@ export const DefaultSlasherConfig: SlasherConfig = {
   slashValidatorsAlways: [], // Empty by default
   slashValidatorsNever: [], // Empty by default
   slashPrunePenalty: DefaultL1ContractsConfig.slashAmountSmall,
+  slashDataWithholdingPenalty: DefaultL1ContractsConfig.slashAmountSmall,
   slashInactivityTargetPercentage: 0.9,
   slashBroadcastedInvalidBlockPenalty: DefaultL1ContractsConfig.slashAmountSmall,
   slashInactivityPenalty: DefaultL1ContractsConfig.slashAmountSmall,
@@ -71,9 +72,14 @@ export const slasherConfigMappings: ConfigMappingsType<SlasherConfig> = {
   },
   slashPrunePenalty: {
     env: 'SLASH_PRUNE_PENALTY',
-    description: 'Penalty amount for slashing validators of a pruned epoch (set to 0 to disable).',
+    description: 'Penalty amount for slashing validators of a valid pruned epoch (set to 0 to disable).',
     ...bigintConfigHelper(DefaultSlasherConfig.slashPrunePenalty),
   },
+  slashDataWithholdingPenalty: {
+    env: 'SLASH_DATA_WITHHOLDING_PENALTY',
+    description: 'Penalty amount for slashing validators for data withholding (set to 0 to disable).',
+    ...bigintConfigHelper(DefaultSlasherConfig.slashDataWithholdingPenalty),
+  },
   slashBroadcastedInvalidBlockPenalty: {
     env: 'SLASH_INVALID_BLOCK_PENALTY',
     description: 'Penalty amount for slashing a validator for an invalid block.',

yarn-project/slasher/src/watchers/epoch_prune_watcher.test.ts

@@ -28,7 +28,8 @@ describe('EpochPruneWatcher', () => {
   let txProvider: MockProxy<Pick<ITxProvider, 'getAvailableTxs'>>;
   let blockBuilder: MockProxy<IFullNodeBlockBuilder>;
   let fork: MockProxy<MerkleTreeWriteOperations>;
-  const penalty = BigInt(1000000000000000000n);
+  const validEpochPrunedPenalty = BigInt(1000000000000000000n);
+  const dataWithholdingPenalty = BigInt(2000000000000000000n);
 
   beforeEach(async () => {
     l2BlockSource = new MockL2BlockSource() as unknown as L2BlockSourceEventEmitter;
@@ -40,7 +41,10 @@ describe('EpochPruneWatcher', () => {
     fork = mock<MerkleTreeWriteOperations>();
     blockBuilder.getFork.mockResolvedValue(fork);
 
-    watcher = new EpochPruneWatcher(l2BlockSource, l1ToL2MessageSource, epochCache, txProvider, blockBuilder, penalty);
+    watcher = new EpochPruneWatcher(l2BlockSource, l1ToL2MessageSource, epochCache, txProvider, blockBuilder, {
+      slashPrunePenalty: validEpochPrunedPenalty,
+      slashDataWithholdingPenalty: dataWithholdingPenalty,
+    });
     await watcher.start();
   });
 
@@ -79,13 +83,13 @@ describe('EpochPruneWatcher', () => {
     expect(emitSpy).toHaveBeenCalledWith(WANT_TO_SLASH_EVENT, [
       {
         validator: EthAddress.fromString(committee[0]),
-        amount: penalty,
+        amount: dataWithholdingPenalty,
         offenseType: OffenseType.DATA_WITHHOLDING,
         epochOrSlot: 1n,
       },
       {
         validator: EthAddress.fromString(committee[1]),
-        amount: penalty,
+        amount: dataWithholdingPenalty,
         offenseType: OffenseType.DATA_WITHHOLDING,
         epochOrSlot: 1n,
       },
@@ -129,13 +133,13 @@ describe('EpochPruneWatcher', () => {
     expect(emitSpy).toHaveBeenCalledWith(WANT_TO_SLASH_EVENT, [
       {
         validator: EthAddress.fromString(committee[0]),
-        amount: penalty,
+        amount: validEpochPrunedPenalty,
         offenseType: OffenseType.VALID_EPOCH_PRUNED,
         epochOrSlot: 1n,
       },
       {
         validator: EthAddress.fromString(committee[1]),
-        amount: penalty,
+        amount: validEpochPrunedPenalty,
         offenseType: OffenseType.VALID_EPOCH_PRUNED,
         epochOrSlot: 1n,
       },

yarn-project/slasher/src/watchers/epoch_prune_watcher.ts

@@ -22,6 +22,11 @@ import EventEmitter from 'node:events';
 
 import { WANT_TO_SLASH_EVENT, type WantToSlashArgs, type Watcher, type WatcherEmitter } from '../watcher.js';
 
+type EpochPruneWatcherPenalties = {
+  slashPrunePenalty: bigint;
+  slashDataWithholdingPenalty: bigint;
+};
+
 /**
  * This watcher is responsible for detecting chain prunes and creating slashing arguments for the committee.
  * It only wants to slash if:
@@ -40,10 +45,12 @@ export class EpochPruneWatcher extends (EventEmitter as new () => WatcherEmitter
     private epochCache: EpochCache,
     private txProvider: Pick<ITxProvider, 'getAvailableTxs'>,
     private blockBuilder: IFullNodeBlockBuilder,
-    private penalty: bigint,
+    private penalties: EpochPruneWatcherPenalties,
   ) {
     super();
-    this.log.info(`EpochPruneWatcher initialized with penalty ${penalty}`);
+    this.log.verbose(
+      `EpochPruneWatcher initialized with penalties: valid epoch pruned=${penalties.slashPrunePenalty} data withholding=${penalties.slashDataWithholdingPenalty}`,
+    );
   }
 
   public start() {
@@ -161,9 +168,13 @@ export class EpochPruneWatcher extends (EventEmitter as new () => WatcherEmitter
     offenseType: OffenseType,
     epochOrSlot: bigint,
   ): WantToSlashArgs[] {
+    const penalty =
+      offenseType === OffenseType.DATA_WITHHOLDING
+        ? this.penalties.slashDataWithholdingPenalty
+        : this.penalties.slashPrunePenalty;
     return validators.map(v => ({
       validator: v,
-      amount: this.penalty,
+      amount: penalty,
       offenseType,
       epochOrSlot,
     }));

yarn-project/stdlib/src/interfaces/aztec-node-admin.test.ts

@@ -141,6 +141,7 @@ class MockAztecNodeAdmin implements AztecNodeAdmin {
       slashValidatorsAlways: [],
       slashValidatorsNever: [],
       slashPrunePenalty: 1000n,
+      slashDataWithholdingPenalty: 1000n,
       slashInactivityTargetPercentage: 0.5,
       slashInactivityPenalty: 1000n,
       slashBroadcastedInvalidBlockPenalty: 1n,

yarn-project/stdlib/src/interfaces/slasher.ts

@@ -14,6 +14,7 @@ export interface SlasherConfig {
   slashValidatorsNever: EthAddress[]; // Array of validator addresses
   slashInactivityTargetPercentage: number; // 0-1, 0.9 means 90%. Must be greater than 0
   slashPrunePenalty: bigint;
+  slashDataWithholdingPenalty: bigint;
   slashInactivityPenalty: bigint;
   slashBroadcastedInvalidBlockPenalty: bigint;
   slashProposeInvalidAttestationsPenalty: bigint;
@@ -31,6 +32,7 @@ export const SlasherConfigSchema = z.object({
   slashValidatorsAlways: z.array(schemas.EthAddress),
   slashValidatorsNever: z.array(schemas.EthAddress),
   slashPrunePenalty: schemas.BigInt,
+  slashDataWithholdingPenalty: schemas.BigInt,
   slashInactivityTargetPercentage: z.number(),
   slashInactivityPenalty: schemas.BigInt,
   slashProposeInvalidAttestationsPenalty: schemas.BigInt,

yarn-project/stdlib/src/slashing/helpers.ts

@@ -48,15 +48,17 @@ export function getPenaltyForOffense(
     | 'slashAttestDescendantOfInvalidPenalty'
     | 'slashBroadcastedInvalidBlockPenalty'
     | 'slashPrunePenalty'
+    | 'slashDataWithholdingPenalty'
     | 'slashUnknownPenalty'
     | 'slashInactivityPenalty'
     | 'slashProposeInvalidAttestationsPenalty'
   >,
 ) {
   switch (offense) {
     case OffenseType.VALID_EPOCH_PRUNED:
-    case OffenseType.DATA_WITHHOLDING:
       return config.slashPrunePenalty;
+    case OffenseType.DATA_WITHHOLDING:
+      return config.slashDataWithholdingPenalty;
     case OffenseType.INACTIVITY:
       return config.slashInactivityPenalty;
     case OffenseType.PROPOSED_INSUFFICIENT_ATTESTATIONS:
@@ -69,8 +71,8 @@ export function getPenaltyForOffense(
     case OffenseType.UNKNOWN:
       return config.slashUnknownPenalty;
     default: {
-      const _: never = offense;
-      throw new Error(`Unknown offense type: ${offense}`);
+      const _exhaustiveCheck: never = offense;
+      throw new Error(`Unknown offense type: ${_exhaustiveCheck}`);
     }
   }
 }
@@ -89,8 +91,8 @@ export function getTimeUnitForOffense(offense: OffenseType): 'epoch' | 'slot' {
     case OffenseType.VALID_EPOCH_PRUNED:
       return 'epoch';
     default: {
-      const _: never = offense;
-      throw new Error(`Unknown offense type: ${offense}`);
+      const _exhaustiveCheck: never = offense;
+      throw new Error(`Unknown offense type: ${_exhaustiveCheck}`);
     }
   }
 }