Spec update to v0.1 (#88)

* update based on https://github.com/ethereum/eth2.0-specs/pull/483 * more spec updates
2025-01-22 04:24:05 +00:00 · 2019-02-07 10:43:21 +00:00 · 2019-02-07 10:43:21 +00:00 · 2d71b998c7
commit 2d71b998c7
parent 788b093284
6 changed files with 33 additions and 72 deletions
--- a/beacon_chain/beacon_node.nim
+++ b/beacon_chain/beacon_node.nim
@ -206,17 +206,13 @@ proc proposeBlock(node: BeaconNode,
      let ok = updateState(state, node.headBlockRoot, none[BeaconBlock](), {})
      doAssert ok

-  let
-    randaoCommitment = node.beaconState.validator_registry[validator.idx].randao_commitment
-    randaoReveal =  await validator.randaoReveal(randaoCommitment)
-
  var blockBody = BeaconBlockBody(
    attestations: node.attestationPool.getAttestationsForBlock(node.beaconState, slot))

  var newBlock = BeaconBlock(
    slot: slot,
    parent_root: node.headBlockRoot,
-    randao_reveal: randaoReveal,
+    randao_reveal: ValidatorSig(), # TODO probably wrong
    eth1_data: node.mainchainMonitor.getBeaconBlockRef(),
    signature: ValidatorSig(), # we need the rest of the block first!
    body: blockBody)
--- a/beacon_chain/spec/beaconstate.nim
+++ b/beacon_chain/spec/beaconstate.nim
@ -26,12 +26,10 @@ func sum_effective_balances*(
 func validate_proof_of_possession(state: BeaconState,
                                  pubkey: ValidatorPubKey,
                                  proof_of_possession: ValidatorSig,
-                                  withdrawal_credentials: Eth2Digest,
-                                  randao_commitment: Eth2Digest): bool =
+                                  withdrawal_credentials: Eth2Digest): bool =
  let proof_of_possession_data = DepositInput(
    pubkey: pubkey,
    withdrawal_credentials: withdrawal_credentials,
-    randao_commitment: randao_commitment
  )

  bls_verify(
@ -57,8 +55,7 @@ func process_deposit(state: var BeaconState,
    # TODO return error; currently, just fails if ever called
    # but hadn't been set up to run at all
    doAssert validate_proof_of_possession(
-      state, pubkey, proof_of_possession, withdrawal_credentials,
-      randao_commitment)
+      state, pubkey, proof_of_possession, withdrawal_credentials)

  let validator_pubkeys = state.validator_registry.mapIt(it.pubkey)

@ -67,13 +64,10 @@ func process_deposit(state: var BeaconState,
    let validator = Validator(
      pubkey: pubkey,
      withdrawal_credentials: withdrawal_credentials,
-      randao_commitment: randao_commitment,
-      randao_layers: 0,
      activation_epoch: FAR_FUTURE_EPOCH,
      exit_epoch: FAR_FUTURE_EPOCH,
      withdrawal_epoch: FAR_FUTURE_EPOCH,
      penalized_epoch: FAR_FUTURE_EPOCH,
-      exit_count: 0,
      status_flags: 0,
    )

@ -121,10 +115,6 @@ func exit_validator*(state: var BeaconState,

  validator.exit_epoch = get_entry_exit_effect_epoch(get_current_epoch(state))

-  # The following updates only occur if not previous exited
-  state.validator_registry_exit_count += 1
-  validator.exit_count = state.validator_registry_exit_count
-
 func process_penalties_and_exits(state: var BeaconState) =
  let
    current_epoch = get_current_epoch(state)
@ -188,7 +178,6 @@ func get_initial_beacon_state*(
    ),

    validator_registry_update_epoch: GENESIS_EPOCH,
-    validator_registry_exit_count: 0,
    validator_registry_delta_chain_tip: ZERO_HASH,

    # Randomness and committees
--- a/beacon_chain/spec/datatypes.nim
+++ b/beacon_chain/spec/datatypes.nim
@ -259,14 +259,16 @@ type
    proof_of_possession*: ValidatorSig ##\
    ## BLS proof of possession (a BLS signature)

+  # https://github.com/ethereum/eth2.0-specs/blob/v0.1/specs/core/0_beacon-chain.md#exit
  Exit* = object
-    # Minimum slot for processing exit
-    slot*: uint64
+    # Minimum epoch for processing exit
+    epoch*: uint64
    # Index of the exiting validator
    validator_index*: ValidatorIndex
    # Validator signature
    signature*: ValidatorSig

+  # https://github.com/ethereum/eth2.0-specs/blob/v0.1/specs/core/0_beacon-chain.md#beaconblock
  BeaconBlock* = object
    ## For each slot, a proposer is chosen from the validator pool to propose
    ## a new block. Once the block as been proposed, it is transmitted to
@ -281,7 +283,7 @@ type
    state_root*: Eth2Digest ##\
    ##\ The state root, _after_ this block has been processed

-    randao_reveal*: Eth2Digest ##\
+    randao_reveal*: ValidatorSig ##\
    ## Proposer RANDAO reveal

    eth1_data*: Eth1Data
@ -291,6 +293,7 @@ type

    body*: BeaconBlockBody

+  # https://github.com/ethereum/eth2.0-specs/blob/v0.1/specs/core/0_beacon-chain.md#beaconblockbody
  BeaconBlockBody* = object
    proposer_slashings*: seq[ProposerSlashing]
    attester_slashings*: seq[AttesterSlashing]
@ -298,12 +301,14 @@ type
    deposits*: seq[Deposit]
    exits*: seq[Exit]

+  # https://github.com/ethereum/eth2.0-specs/blob/v0.1/specs/core/0_beacon-chain.md#proposalsigneddata
  ProposalSignedData* = object
    slot*: uint64
    shard*: uint64 ##\
    ## Shard number (or `BEACON_CHAIN_SHARD_NUMBER` for beacon chain)
    block_root*: Eth2Digest

+  # https://github.com/ethereum/eth2.0-specs/blob/v0.1/specs/core/0_beacon-chain.md#beaconstate
  BeaconState* = object
    slot*: uint64
    genesis_time*: uint64
@ -316,7 +321,6 @@ type
    ## Validator balances in Gwei!

    validator_registry_update_epoch*: uint64
-    validator_registry_exit_count*: uint64

    # TODO remove, not in spec anymore
    validator_registry_delta_chain_tip*: Eth2Digest ##\
@ -356,19 +360,6 @@ type
    pubkey*: ValidatorPubKey
    withdrawal_credentials*: Eth2Digest

-    # TODO remove randao_commitment, randao_layers
-    randao_commitment*: Eth2Digest ##\
-    ## RANDAO commitment created by repeatedly taking the hash of a secret value
-    ## so as to create "onion layers" around it. For every block that a
-    ## validator proposes, one level of the onion is peeled. See:
-    ## * https://ethresear.ch/t/rng-exploitability-analysis-assuming-pure-randao-based-main-chain/1825
-    ## * repeat_hash
-    ## * processRandaoReveal
-
-    randao_layers*: uint64 ##\
-    ## Number of proposals the proposer missed, and thus the number of times to
-    ## apply hash function to randao reveal
-
    activation_epoch*: EpochNumber ##\
    ## Slot when validator activated

@ -381,9 +372,6 @@ type
    penalized_epoch*: EpochNumber ##\
    ## Slot when validator penalized

-    exit_count*: uint64 ##\
-    ## Exit counter when validator exited (or 0)
-
    status_flags*: uint64

  Crosslink* = object
--- a/beacon_chain/spec/helpers.nim
+++ b/beacon_chain/spec/helpers.nim
@ -140,9 +140,10 @@ func get_fork_version*(fork: Fork, epoch: EpochNumber): uint64 =
    fork.current_version

 func get_domain*(
-    fork: Fork, slot: uint64, domain_type: SignatureDomain): uint64 =
+    fork: Fork, epoch: EpochNumber, domain_type: SignatureDomain): uint64 =
  # TODO Slot overflow? Or is slot 32 bits for all intents and purposes?
-  (get_fork_version(fork, slot) shl 32) + domain_type.uint32
+  # Get the domain number that represents the fork meta and signature domain.
+  (get_fork_version(fork, epoch) shl 32) + domain_type.uint32

 func is_power_of_2*(v: uint64): bool = (v and (v-1)) == 0

--- a/beacon_chain/state_transition.nim
+++ b/beacon_chain/state_transition.nim
@ -85,21 +85,23 @@ proc processRandao(

  if skipValidation notin flags:
    # Check that proposer commit and reveal match
-    let expected = repeat_hash(blck.randao_reveal, proposer.randao_layers)
-    if expected != proposer.randao_commitment:
-      notice "Randao reveal mismatch", reveal = blck.randao_reveal,
-                                       layers = proposer.randao_layers,
-                                       commitment = proposer.randao_commitment,
-                                       expected
-      return false
+    # TODO re-enable if appropriate
+    #let expected = repeat_hash(blck.randao_reveal, proposer.randao_layers)
+    #if expected != proposer.randao_commitment:
+    #  notice "Randao reveal mismatch", reveal = blck.randao_reveal,
+    #                                   layers = proposer.randao_layers,
+    #                                   commitment = proposer.randao_commitment,
+    #                                   expected
+    #  return false
+    discard

  # Update state and proposer now that we're alright
-  let mix = state.slot mod LATEST_RANDAO_MIXES_LENGTH
-  for i, b in state.latest_randao_mixes[mix].data:
-    state.latest_randao_mixes[mix].data[i] = b xor blck.randao_reveal.data[i]
+  let
+    mix = get_current_epoch(state) mod LATEST_RANDAO_MIXES_LENGTH
+    rr = hash_tree_root_final(blck.randao_reveal).data

-  proposer.randao_commitment = blck.randao_reveal
-  proposer.randao_layers = 0
+  for i, b in state.latest_randao_mixes[mix].data:
+    state.latest_randao_mixes[mix].data[i] = b xor rr[i]

  return true

@ -303,7 +305,7 @@ proc processExits(
    if skipValidation notin flags:
      if not bls_verify(
          validator.pubkey, ZERO_HASH.data, exit.signature,
-          get_domain(state.fork, exit.slot, DOMAIN_EXIT)):
+          get_domain(state.fork, exit.epoch, DOMAIN_EXIT)):
        notice "Exit: invalid signature"
        return false

@ -311,8 +313,8 @@ proc processExits(
      notice "Exit: exit/entry too close"
      return false

-    if not (state.slot >= exit.slot):
-      notice "Exit: bad slot"
+    if not (get_current_epoch(state) >= exit.epoch):
+      notice "Exit: bad epoch"
      return false

    initiate_validator_exit(state, exit.validator_index)
@ -336,16 +338,10 @@ func processSlot(state: var BeaconState, previous_block_root: Eth2Digest) =
  ## chain at that time. In case the proposer is missing, it may happen that
  ## the no block is produced during the slot.
  ##
-  ## https://github.com/ethereum/eth2.0-specs/blob/master/specs/core/0_beacon-chain.md#per-slot-processing
-
+  ## https://github.com/ethereum/eth2.0-specs/blob/v0.1/specs/core/0_beacon-chain.md#per-slot-processing
  state.slot += 1
-  state.validator_registry[
-    get_beacon_proposer_index(state, state.slot)].randao_layers += 1
-  state.latest_randao_mixes[state.slot mod LATEST_RANDAO_MIXES_LENGTH] =
-    state.latest_randao_mixes[(state.slot - 1) mod LATEST_RANDAO_MIXES_LENGTH]
  state.latest_block_roots[(state.slot - 1) mod LATEST_BLOCK_ROOTS_LENGTH] =
    previous_block_root
-
  if state.slot mod LATEST_BLOCK_ROOTS_LENGTH == 0:
    state.batched_block_roots.add(merkle_root(state.latest_block_roots))

--- a/tests/testutil.nim
+++ b/tests/testutil.nim
@ -28,15 +28,6 @@ func hackPrivKey(v: Validator): ValidatorPrivKey =
    min(sizeof(v.withdrawal_credentials.data), sizeof(i)))
  makeValidatorPrivKey(i)

-func hackReveal(v: Validator): Eth2Digest =
-  result = v.withdrawal_credentials
-  for i in 0..randaoRounds:
-    let tmp = repeat_hash(result, 1)
-    if tmp == v.randao_commitment:
-      return
-    result = tmp
-  raise newException(Exception, "can't find randao hack value")
-
 func makeDeposit(i: int, flags: UpdateFlags): Deposit =
  ## Ugly hack for now: we stick the private key in withdrawal_credentials
  ## which means we can repro private key and randao reveal from this data,
@ -114,7 +105,7 @@ proc addBlock*(
      slot: state.slot + 1,
      parent_root: previous_block_root,
      state_root: Eth2Digest(), # we need the new state first
-      randao_reveal: hackReveal(proposer),
+      randao_reveal: ValidatorSig(), # TODO
      eth1_data: Eth1Data(), # TODO
      signature: ValidatorSig(), # we need the rest of the block first!
      body: body