implement terminal-total-difficulty-override; keep kintsugi TTDs consistent (#3118)

* implement terminal-total-difficulty-override; keep TTD consistent for m2 scripts/docs

* use Option[uint64] instead of uint64

beacon_chain/conf.nim

@@ -355,6 +355,13 @@ type
         defaultValueDesc: "50"
         name: "sync-horizon" }: uint64
 
+      # https://github.com/ethereum/consensus-specs/blob/v1.1.5/specs/merge/client-settings.md#override-terminal-total-difficulty
+      terminalTotalDifficultyOverride* {.
+        hidden
+        desc: "Override pre-configured TERMINAL_TOTAL_DIFFICULTY parameter"
+        name: "terminal-total-difficulty-override"
+      }: Option[uint64]
+
     of createTestnet:
       testnetDepositsFile* {.
         desc: "A LaunchPad deposits file for the genesis state validators"

beacon_chain/eth1/eth1_monitor.nim

@@ -184,21 +184,21 @@ when hasGenesisDetection:
   func isGenesisCandidate(m: Eth1Monitor, blk: Eth1Block): bool =
     m.hasEnoughValidators(blk) and m.isAfterMinGenesisTime(blk)
 
-  proc findGenesisBlockInRange(m: Eth1Monitor, startBlock, endBlock: Eth1Block):
+  func findGenesisBlockInRange(m: Eth1Monitor, startBlock, endBlock: Eth1Block):
                                Future[Eth1Block] {.async, gcsafe.}
 
-  proc signalGenesis(m: Eth1Monitor, genesisState: BeaconStateRef) =
+  func signalGenesis(m: Eth1Monitor, genesisState: BeaconStateRef) =
     m.genesisState = genesisState
 
     if not m.genesisStateFut.isNil:
       m.genesisStateFut.complete()
       m.genesisStateFut = nil
 
-  proc allGenesisDepositsUpTo(m: Eth1Monitor, totalDeposits: uint64): seq[DepositData] =
+  func allGenesisDepositsUpTo(m: Eth1Monitor, totalDeposits: uint64): seq[DepositData] =
     for i in 0'u64 ..< totalDeposits:
       result.add m.db.genesisDeposits.get(i)
 
-  proc createGenesisState(m: Eth1Monitor, eth1Block: Eth1Block): BeaconStateRef =
+  func createGenesisState(m: Eth1Monitor, eth1Block: Eth1Block): BeaconStateRef =
     notice "Generating genesis state",
       blockNum = eth1Block.number,
       blockHash = eth1Block.voteData.block_hash,
@@ -217,7 +217,7 @@ when hasGenesisDetection:
     if eth1Block.activeValidatorsCount != 0:
       doAssert result.validators.lenu64 == eth1Block.activeValidatorsCount
 
-  proc produceDerivedData(m: Eth1Monitor, deposit: DepositData) =
+  func produceDerivedData(m: Eth1Monitor, deposit: DepositData) =
     let htr = hash_tree_root(deposit)
 
     if verify_deposit_signature(m.cfg, deposit):
@@ -229,7 +229,7 @@ when hasGenesisDetection:
           withdrawal_credentials: deposit.withdrawal_credentials)
         m.genesisValidatorKeyToIndex[pubkey] = idx
 
-  proc processGenesisDeposit*(m: Eth1Monitor, newDeposit: DepositData) =
+  func processGenesisDeposit*(m: Eth1Monitor, newDeposit: DepositData) =
     m.db.genesisDeposits.add newDeposit
     m.produceDerivedData(newDeposit)
 
@@ -420,7 +420,7 @@ template readJsonField(j: JsonNode, fieldName: string, ValueType: type): untyped
 template init[N: static int](T: type DynamicBytes[N, N]): T =
   T newSeq[byte](N)
 
-proc depositEventsToBlocks(depositsList: JsonNode): seq[Eth1Block] {.
+func depositEventsToBlocks(depositsList: JsonNode): seq[Eth1Block] {.
     raises: [Defect, CatchableError].} =
   if depositsList.kind != JArray:
     raise newException(CatchableError,
@@ -491,7 +491,7 @@ when hasDepositRootChecks:
     awaitWithTimeout(fut, timeout):
       raise newException(DataProviderTimeout, "Timeout")
 
-  proc fetchDepositContractData(p: Web3DataProviderRef, blk: Eth1Block):
+  func fetchDepositContractData(p: Web3DataProviderRef, blk: Eth1Block):
                                 Future[DepositContractDataStatus] {.async.} =
     let
       depositRoot = p.ns.get_deposit_root.call(blockNumber = blk.number)
@@ -584,7 +584,7 @@ proc pruneOldBlocks(chain: var Eth1Chain, depositIndex: uint64) =
            newTailBlock = lastBlock.voteData.block_hash,
            depositsCount = lastBlock.voteData.deposit_count
 
-proc advanceMerkleizer(chain: Eth1Chain,
+func advanceMerkleizer(chain: Eth1Chain,
                        merkleizer: var DepositsMerkleizer,
                        depositIndex: uint64): bool =
   if chain.blocks.len == 0:
@@ -610,7 +610,7 @@ proc advanceMerkleizer(chain: Eth1Chain,
 
   return merkleizer.getChunkCount == depositIndex
 
-proc getDepositsRange(chain: Eth1Chain, first, last: uint64): seq[DepositData] =
+func getDepositsRange(chain: Eth1Chain, first, last: uint64): seq[DepositData] =
   # TODO It's possible to make this faster by performing binary search that
   #      will locate the blocks holding the `first` and `last` indices.
   # TODO There is an assumption here that the requested range will be present
@@ -629,7 +629,7 @@ proc getDepositsRange(chain: Eth1Chain, first, last: uint64): seq[DepositData] =
       if globalIdx >= first and globalIdx < last:
         result.add blk.deposits[i]
 
-proc lowerBound(chain: Eth1Chain, depositCount: uint64): Eth1Block =
+func lowerBound(chain: Eth1Chain, depositCount: uint64): Eth1Block =
   # TODO: This can be replaced with a proper binary search in the
   #       future, but the `algorithm` module currently requires an
   #       `openArray`, which the `deques` module can't provide yet.
@@ -817,7 +817,7 @@ proc safeCancel(fut: var Future[void]) =
     fut.cancel()
   fut = nil
 
-proc clear(chain: var Eth1Chain) =
+func clear(chain: var Eth1Chain) =
   chain.blocks.clear()
   chain.blocksByHash.clear()
   chain.hasConsensusViolation = false
@@ -844,7 +844,7 @@ proc stop*(m: Eth1Monitor) {.async.} =
 const
   votedBlocksSafetyMargin = 50
 
-proc earliestBlockOfInterest(m: Eth1Monitor): Eth1BlockNumber =
+func earliestBlockOfInterest(m: Eth1Monitor): Eth1BlockNumber =
   m.latestEth1BlockNumber - (2 * m.cfg.ETH1_FOLLOW_DISTANCE) - votedBlocksSafetyMargin
 
 

beacon_chain/nimbus_beacon_node.nim

@@ -1505,7 +1505,12 @@ proc doRunBeaconNode(config: var BeaconNodeConf, rng: ref BrHmacDrbgContext) {.r
   # letting the default Ctrl+C handler exit is safe, since we only read from
   # the db.
 
-  let metadata = config.loadEth2Network()
+  var metadata = config.loadEth2Network()
+
+  # https://github.com/ethereum/consensus-specs/blob/v1.1.5/specs/merge/client-settings.md#override-terminal-total-difficulty
+  if config.terminalTotalDifficultyOverride.isSome:
+    metadata.cfg.TERMINAL_TOTAL_DIFFICULTY =
+      config.terminalTotalDifficultyOverride.get.u256
 
   # Updating the config based on the metadata certainly is not beautiful but it
   # works

docs/neth-m2-nimbus.md

@@ -20,7 +20,7 @@ cd Nethermind.Runner
 run Nethermind
 ```
 rm -rf bin/Release/net5.0/nethermind_db
-dotnet run -c Release -- --config themerge_kintsugi_m2 --Merge.TerminalTotalDifficulty 100
+dotnet run -c Release -- --config themerge_kintsugi_m2 --Merge.TerminalTotalDifficulty 0
 ```
 
 # Verify that Nimbus runs through test vectors