Split state_transition (#301)
This commit is contained in:
Mamy Ratsimbazafy
Dustin Brody
parent
0d37ed7a2a
commit
214860cb88
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# beacon_chain
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# Copyright (c) 2018-2019 Status Research & Development GmbH
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# Licensed and distributed under either of
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# * MIT license (license terms in the root directory or at http://opensource.org/licenses/MIT).
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# * Apache v2 license (license terms in the root directory or at http://www.apache.org/licenses/LICENSE-2.0).
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# at your option. This file may not be copied, modified, or distributed except according to those terms.
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# State transition - block processing, as described in
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# https://github.com/ethereum/eth2.0-specs/blob/master/specs/core/0_beacon-chain.md#beacon-chain-state-transition-function
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#
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# The purpose of this code right is primarily educational, to help piece
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# together the mechanics of the beacon state and to discover potential problem
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# areas.
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#
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# The entry point is `process_block` which is at the bottom of this file.
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#
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# General notes about the code (TODO):
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# * It's inefficient - we quadratically copy, allocate and iterate when there
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# are faster options
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# * Weird styling - the sections taken from the spec use python styling while
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# the others use NEP-1 - helps grepping identifiers in spec
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# * We mix procedural and functional styles for no good reason, except that the
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# spec does so also.
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# * There are likely lots of bugs.
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# * For indices, we get a mix of uint64, ValidatorIndex and int - this is currently
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# swept under the rug with casts
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# * The spec uses uint64 for data types, but functions in the spec often assume
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# signed bigint semantics - under- and overflows ensue
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# * Sane error handling is missing in most cases (yay, we'll get the chance to
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# debate exceptions again!)
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# When updating the code, add TODO sections to mark where there are clear
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# improvements to be made - other than that, keep things similar to spec for
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# now.
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import # TODO - cleanup imports
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algorithm, collections/sets, chronicles, math, options, sequtils, sets, tables,
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../extras, ../ssz, ../beacon_node_types,
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beaconstate, bitfield, crypto, datatypes, digest, helpers, validator
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# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#block-header
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proc processBlockHeader(
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state: var BeaconState, blck: BeaconBlock, flags: UpdateFlags,
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stateCache: var StateCache): bool =
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# Verify that the slots match
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if not (blck.slot == state.slot):
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notice "Block header: slot mismatch",
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block_slot = humaneSlotNum(blck.slot),
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state_slot = humaneSlotNum(state.slot)
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return false
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# Verify that the parent matches
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if skipValidation notin flags and not (blck.parent_root ==
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signing_root(state.latest_block_header)):
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notice "Block header: previous block root mismatch",
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latest_block_header = state.latest_block_header,
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blck = shortLog(blck),
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latest_block_header_root = shortLog(signing_root(state.latest_block_header))
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return false
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# Save current block as the new latest block
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state.latest_block_header = BeaconBlockHeader(
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slot: blck.slot,
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parent_root: blck.parent_root,
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body_root: hash_tree_root(blck.body),
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)
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# Verify proposer is not slashed
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let proposer =
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state.validator_registry[get_beacon_proposer_index(state, stateCache)]
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if proposer.slashed:
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notice "Block header: proposer slashed"
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return false
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# Verify proposer signature
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if skipValidation notin flags and not bls_verify(
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proposer.pubkey,
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signing_root(blck).data,
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blck.signature,
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get_domain(state, DOMAIN_BEACON_PROPOSER)):
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notice "Block header: invalid block header",
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proposer_pubkey = proposer.pubkey,
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block_root = shortLog(signing_root(blck)),
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block_signature = blck.signature
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return false
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true
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# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#randao
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proc processRandao(
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state: var BeaconState, body: BeaconBlockBody, flags: UpdateFlags,
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stateCache: var StateCache): bool =
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let
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proposer_index = get_beacon_proposer_index(state, stateCache)
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proposer = addr state.validator_registry[proposer_index]
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# Verify that the provided randao value is valid
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if skipValidation notin flags:
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if not bls_verify(
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proposer.pubkey,
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hash_tree_root(get_current_epoch(state).uint64).data,
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body.randao_reveal,
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get_domain(state, DOMAIN_RANDAO)):
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notice "Randao mismatch", proposer_pubkey = proposer.pubkey,
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message = get_current_epoch(state),
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signature = body.randao_reveal,
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slot = state.slot
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return false
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# Mix it in
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let
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mix = get_current_epoch(state) mod LATEST_RANDAO_MIXES_LENGTH
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rr = eth2hash(body.randao_reveal.getBytes()).data
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for i, b in state.latest_randao_mixes[mix].data:
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state.latest_randao_mixes[mix].data[i] = b xor rr[i]
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true
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# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#eth1-data
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func processEth1Data(state: var BeaconState, body: BeaconBlockBody) =
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state.eth1_data_votes.add body.eth1_data
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if state.eth1_data_votes.count(body.eth1_data) * 2 >
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SLOTS_PER_ETH1_VOTING_PERIOD:
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state.latest_eth1_data = body.eth1_data
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# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#is_slashable_validator
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func is_slashable_validator(validator: Validator, epoch: Epoch): bool =
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# Check if ``validator`` is slashable.
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(not validator.slashed) and
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(validator.activation_epoch <= epoch) and
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(epoch < validator.withdrawable_epoch)
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# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#proposer-slashings
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proc processProposerSlashings(
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state: var BeaconState, blck: BeaconBlock, flags: UpdateFlags,
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stateCache: var StateCache): bool =
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if len(blck.body.proposer_slashings) > MAX_PROPOSER_SLASHINGS:
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notice "PropSlash: too many!",
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proposer_slashings = len(blck.body.proposer_slashings)
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return false
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for proposer_slashing in blck.body.proposer_slashings:
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let proposer = state.validator_registry[proposer_slashing.proposer_index.int]
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# Verify that the epoch is the same
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if not (slot_to_epoch(proposer_slashing.header_1.slot) ==
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slot_to_epoch(proposer_slashing.header_2.slot)):
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notice "PropSlash: epoch mismatch"
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return false
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# But the headers are different
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if not (proposer_slashing.header_1 != proposer_slashing.header_2):
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notice "PropSlash: headers not different"
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return false
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# Check proposer is slashable
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if not is_slashable_validator(proposer, get_current_epoch(state)):
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notice "PropSlash: slashed proposer"
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return false
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# Signatures are valid
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if skipValidation notin flags:
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for i, header in @[proposer_slashing.header_1, proposer_slashing.header_2]:
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if not bls_verify(
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proposer.pubkey,
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signing_root(header).data,
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header.signature,
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get_domain(
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state, DOMAIN_BEACON_PROPOSER, slot_to_epoch(header.slot))):
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notice "PropSlash: invalid signature",
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signature_index = i
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return false
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slashValidator(
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state, proposer_slashing.proposer_index.ValidatorIndex, stateCache)
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true
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# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#is_slashable_attestation_data
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func is_slashable_attestation_data(
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data_1: AttestationData, data_2: AttestationData): bool =
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## Check if ``data_1`` and ``data_2`` are slashable according to Casper FFG
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## rules.
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# Double vote
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(data_1 != data_2 and data_1.target_epoch == data_2.target_epoch) or
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# Surround vote
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(data_1.source_epoch < data_2.source_epoch and
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data_2.target_epoch < data_1.target_epoch)
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# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#attester-slashings
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proc processAttesterSlashings(state: var BeaconState, blck: BeaconBlock,
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stateCache: var StateCache): bool =
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# Process ``AttesterSlashing`` operation.
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if len(blck.body.attester_slashings) > MAX_ATTESTER_SLASHINGS:
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notice "CaspSlash: too many!"
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return false
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result = true
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for attester_slashing in blck.body.attester_slashings:
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let
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attestation_1 = attester_slashing.attestation_1
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attestation_2 = attester_slashing.attestation_2
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if not is_slashable_attestation_data(
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attestation_1.data, attestation_2.data):
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notice "CaspSlash: surround or double vote check failed"
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return false
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if not validate_indexed_attestation(state, attestation_1):
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notice "CaspSlash: invalid votes 1"
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return false
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if not validate_indexed_attestation(state, attestation_2):
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notice "CaspSlash: invalid votes 2"
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return false
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var slashed_any = false
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## TODO there's a lot of sorting/set construction here and
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## verify_indexed_attestation, but go by spec unless there
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## is compelling perf evidence otherwise.
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let attesting_indices_1 =
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attestation_1.custody_bit_0_indices & attestation_1.custody_bit_1_indices
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let attesting_indices_2 =
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attestation_2.custody_bit_0_indices & attestation_2.custody_bit_1_indices
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for index in sorted(toSeq(intersection(toSet(attesting_indices_1),
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toSet(attesting_indices_2)).items), system.cmp):
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if is_slashable_validator(state.validator_registry[index.int],
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get_current_epoch(state)):
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slash_validator(state, index.ValidatorIndex, stateCache)
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slashed_any = true
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result = result and slashed_any
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# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#attestations
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proc processAttestations(
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state: var BeaconState, blck: BeaconBlock, flags: UpdateFlags,
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stateCache: var StateCache): bool =
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## Each block includes a number of attestations that the proposer chose. Each
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## attestation represents an update to a specific shard and is signed by a
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## committee of validators.
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## Here we make sanity checks for each attestation and it to the state - most
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## updates will happen at the epoch boundary where state updates happen in
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## bulk.
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if blck.body.attestations.len > MAX_ATTESTATIONS:
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notice "Attestation: too many!", attestations = blck.body.attestations.len
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return false
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if not blck.body.attestations.allIt(checkAttestation(state, it, flags, stateCache)):
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return false
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# All checks passed - update state
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# Apply the attestations
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var committee_count_cache = initTable[Epoch, uint64]()
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for attestation in blck.body.attestations:
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# Caching
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let
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epoch = attestation.data.target_epoch
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committee_count = if epoch in committee_count_cache:
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committee_count_cache[epoch]
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else:
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get_epoch_committee_count(state, epoch)
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committee_count_cache[epoch] = committee_count
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# Spec content
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let attestation_slot =
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get_attestation_data_slot(state, attestation.data, committee_count)
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let pending_attestation = PendingAttestation(
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data: attestation.data,
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aggregation_bitfield: attestation.aggregation_bitfield,
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inclusion_delay: state.slot - attestation_slot,
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proposer_index: get_beacon_proposer_index(state, stateCache),
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)
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if attestation.data.target_epoch == get_current_epoch(state):
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state.current_epoch_attestations.add(pending_attestation)
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else:
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state.previous_epoch_attestations.add(pending_attestation)
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true
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# https://github.com/ethereum/eth2.0-specs/blob/v0.5.1/specs/core/0_beacon-chain.md#deposits
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proc processDeposits(state: var BeaconState, blck: BeaconBlock): bool =
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if not (len(blck.body.deposits) <= MAX_DEPOSITS):
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notice "processDeposits: too many deposits"
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return false
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for deposit in blck.body.deposits:
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if not process_deposit(state, deposit):
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notice "processDeposits: deposit invalid"
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return false
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true
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# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#voluntary-exits
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proc processVoluntaryExits(
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state: var BeaconState, blck: BeaconBlock, flags: UpdateFlags): bool =
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# Process ``VoluntaryExit`` transaction.
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if len(blck.body.voluntary_exits) > MAX_VOLUNTARY_EXITS:
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notice "Exit: too many!"
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return false
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for exit in blck.body.voluntary_exits:
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let validator = state.validator_registry[exit.validator_index.int]
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# Verify the validator is active
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if not is_active_validator(validator, get_current_epoch(state)):
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notice "Exit: validator not active"
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return false
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# Verify the validator has not yet exited
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if not (validator.exit_epoch == FAR_FUTURE_EPOCH):
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notice "Exit: validator has exited"
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return false
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## Exits must specify an epoch when they become valid; they are not valid
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## before then
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if not (get_current_epoch(state) >= exit.epoch):
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notice "Exit: exit epoch not passed"
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return false
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# Verify the validator has been active long enough
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# TODO detect underflow
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if not (get_current_epoch(state) - validator.activation_epoch >=
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PERSISTENT_COMMITTEE_PERIOD):
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notice "Exit: not in validator set long enough"
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return false
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# Verify signature
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if skipValidation notin flags:
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if not bls_verify(
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validator.pubkey, signing_root(exit).data, exit.signature,
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get_domain(state, DOMAIN_VOLUNTARY_EXIT, exit.epoch)):
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notice "Exit: invalid signature"
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return false
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# Initiate exit
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initiate_validator_exit(state, exit.validator_index.ValidatorIndex)
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true
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# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#transfers
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proc processTransfers(state: var BeaconState, blck: BeaconBlock,
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flags: UpdateFlags, stateCache: var StateCache): bool =
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if not (len(blck.body.transfers) <= MAX_TRANSFERS):
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notice "Transfer: too many transfers"
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return false
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for transfer in blck.body.transfers:
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let sender_balance = state.balances[transfer.sender.int]
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## Verify the amount and fee are not individually too big (for anti-overflow
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## purposes)
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if not (sender_balance >= max(transfer.amount, transfer.fee)):
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notice "Transfer: sender balance too low for transfer amount or fee"
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return false
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# A transfer is valid in only one slot
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if not (state.slot == transfer.slot):
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notice "Transfer: slot mismatch"
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return false
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## Sender must be not yet eligible for activation, withdrawn, or transfer
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## balance over MAX_EFFECTIVE_BALANCE
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if not (
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state.validator_registry[transfer.sender.int].activation_epoch ==
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FAR_FUTURE_EPOCH or
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get_current_epoch(state) >=
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state.validator_registry[
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transfer.sender.int].withdrawable_epoch or
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transfer.amount + transfer.fee + MAX_EFFECTIVE_BALANCE <=
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state.balances[transfer.sender.int]):
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notice "Transfer: only withdrawn or not-activated accounts with sufficient balance can transfer"
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return false
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# Verify that the pubkey is valid
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let wc = state.validator_registry[transfer.sender.int].
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withdrawal_credentials
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if not (wc.data[0] == BLS_WITHDRAWAL_PREFIX and
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wc.data[1..^1] == eth2hash(transfer.pubkey.getBytes).data[1..^1]):
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notice "Transfer: incorrect withdrawal credentials"
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return false
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# Verify that the signature is valid
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if skipValidation notin flags:
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if not bls_verify(
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transfer.pubkey, signing_root(transfer).data, transfer.signature,
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get_domain(state, DOMAIN_TRANSFER)):
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notice "Transfer: incorrect signature"
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return false
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# Process the transfer
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decrease_balance(
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state, transfer.sender.ValidatorIndex, transfer.amount + transfer.fee)
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increase_balance(
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state, transfer.recipient.ValidatorIndex, transfer.amount)
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increase_balance(
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state, get_beacon_proposer_index(state, stateCache), transfer.fee)
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# Verify balances are not dust
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if not (
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0'u64 < state.balances[transfer.sender.int] and
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state.balances[transfer.sender.int] < MIN_DEPOSIT_AMOUNT):
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notice "Transfer: sender balance too low for transfer amount or fee"
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return false
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if not (
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0'u64 < state.balances[transfer.recipient.int] and
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state.balances[transfer.recipient.int] < MIN_DEPOSIT_AMOUNT):
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notice "Transfer: sender balance too low for transfer amount or fee"
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return false
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true
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proc processBlock*(
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state: var BeaconState, blck: BeaconBlock, flags: UpdateFlags,
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stateCache: var StateCache): bool =
|
||||
## When there's a new block, we need to verify that the block is sane and
|
||||
## update the state accordingly
|
||||
|
||||
# TODO when there's a failure, we should reset the state!
|
||||
# TODO probably better to do all verification first, then apply state changes
|
||||
|
||||
if not processBlockHeader(state, blck, flags, stateCache):
|
||||
notice "Block header not valid", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
if not processRandao(state, blck.body, flags, stateCache):
|
||||
debug "[Block processing] Randao failure", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
processEth1Data(state, blck.body)
|
||||
|
||||
if not processProposerSlashings(state, blck, flags, stateCache):
|
||||
debug "[Block processing] Proposer slashing failure", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
if not processAttesterSlashings(state, blck, stateCache):
|
||||
debug "[Block processing] Attester slashing failure", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
if not processAttestations(state, blck, flags, stateCache):
|
||||
debug "[Block processing] Attestation processing failure", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
if not processDeposits(state, blck):
|
||||
debug "[Block processing] Deposit processing failure", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
if not processVoluntaryExits(state, blck, flags):
|
||||
debug "[Block processing] Exit processing failure", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
if not processTransfers(state, blck, flags, stateCache):
|
||||
debug "[Block processing] Transfer processing failure", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
true
|
||||
|
|
@ -0,0 +1,462 @@
|
|||
# beacon_chain
|
||||
# Copyright (c) 2018-2019 Status Research & Development GmbH
|
||||
# Licensed and distributed under either of
|
||||
# * MIT license (license terms in the root directory or at http://opensource.org/licenses/MIT).
|
||||
# * Apache v2 license (license terms in the root directory or at http://www.apache.org/licenses/LICENSE-2.0).
|
||||
# at your option. This file may not be copied, modified, or distributed except according to those terms.
|
||||
|
||||
# State transition - epoch processing, as described in
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/master/specs/core/0_beacon-chain.md#beacon-chain-state-transition-function
|
||||
#
|
||||
# The purpose of this code right is primarily educational, to help piece
|
||||
# together the mechanics of the beacon state and to discover potential problem
|
||||
# areas.
|
||||
#
|
||||
# The entry point is `process_epoch` which is at the bottom of this file.
|
||||
#
|
||||
# General notes about the code (TODO):
|
||||
# * It's inefficient - we quadratically copy, allocate and iterate when there
|
||||
# are faster options
|
||||
# * Weird styling - the sections taken from the spec use python styling while
|
||||
# the others use NEP-1 - helps grepping identifiers in spec
|
||||
# * We mix procedural and functional styles for no good reason, except that the
|
||||
# spec does so also.
|
||||
# * There are likely lots of bugs.
|
||||
# * For indices, we get a mix of uint64, ValidatorIndex and int - this is currently
|
||||
# swept under the rug with casts
|
||||
# * The spec uses uint64 for data types, but functions in the spec often assume
|
||||
# signed bigint semantics - under- and overflows ensue
|
||||
# * Sane error handling is missing in most cases (yay, we'll get the chance to
|
||||
# debate exceptions again!)
|
||||
# When updating the code, add TODO sections to mark where there are clear
|
||||
# improvements to be made - other than that, keep things similar to spec for
|
||||
# now.
|
||||
|
||||
import # TODO - cleanup imports
|
||||
algorithm, collections/sets, chronicles, math, options, sequtils, sets, tables,
|
||||
../extras, ../ssz, ../beacon_node_types,
|
||||
beaconstate, bitfield, crypto, datatypes, digest, helpers, validator
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#helper-functions-1
|
||||
func get_total_active_balance(state: BeaconState): Gwei =
|
||||
return get_total_balance(
|
||||
state,
|
||||
get_active_validator_indices(state, get_current_epoch(state)))
|
||||
|
||||
func get_matching_source_attestations(state: BeaconState, epoch: Epoch):
|
||||
seq[PendingAttestation] =
|
||||
doAssert epoch in @[get_current_epoch(state), get_previous_epoch(state)]
|
||||
if epoch == get_current_epoch(state):
|
||||
state.current_epoch_attestations
|
||||
else:
|
||||
state.previous_epoch_attestations
|
||||
|
||||
func get_matching_target_attestations(state: BeaconState, epoch: Epoch):
|
||||
seq[PendingAttestation] =
|
||||
filterIt(
|
||||
get_matching_source_attestations(state, epoch),
|
||||
it.data.target_root == get_block_root(state, epoch)
|
||||
)
|
||||
|
||||
func get_matching_head_attestations(state: BeaconState, epoch: Epoch):
|
||||
seq[PendingAttestation] =
|
||||
filterIt(
|
||||
get_matching_source_attestations(state, epoch),
|
||||
it.data.beacon_block_root ==
|
||||
get_block_root_at_slot(state, get_attestation_data_slot(state, it.data))
|
||||
)
|
||||
|
||||
func get_unslashed_attesting_indices(
|
||||
state: BeaconState, attestations: seq[PendingAttestation],
|
||||
stateCache: var StateCache): HashSet[ValidatorIndex] =
|
||||
result = initSet[ValidatorIndex]()
|
||||
for a in attestations:
|
||||
result = result.union(get_attesting_indices(
|
||||
state, a.data, a.aggregation_bitfield, stateCache))
|
||||
|
||||
for index in result:
|
||||
if state.validator_registry[index].slashed:
|
||||
result.excl index
|
||||
|
||||
func get_attesting_balance(
|
||||
state: BeaconState, attestations: seq[PendingAttestation],
|
||||
stateCache: var StateCache): Gwei =
|
||||
get_total_balance(state, get_unslashed_attesting_indices(
|
||||
state, attestations, stateCache))
|
||||
|
||||
# Not exactly in spec, but for get_winning_crosslink_and_attesting_indices
|
||||
func lowerThan(candidate, current: Eth2Digest): bool =
|
||||
# return true iff candidate is "lower" than current, per spec rule:
|
||||
# "ties broken in favor of lexicographically higher hash
|
||||
for i, v in current.data:
|
||||
if v > candidate.data[i]: return true
|
||||
false
|
||||
|
||||
func get_winning_crosslink_and_attesting_indices(
|
||||
state: BeaconState, epoch: Epoch, shard: Shard,
|
||||
stateCache: var StateCache): tuple[a: Crosslink, b: HashSet[ValidatorIndex]] =
|
||||
let
|
||||
attestations =
|
||||
filterIt(
|
||||
get_matching_source_attestations(state, epoch),
|
||||
it.data.crosslink.shard == shard)
|
||||
# TODO don't keep h_t_r'ing state.current_crosslinks[shard]
|
||||
crosslinks =
|
||||
filterIt(
|
||||
mapIt(attestations, it.data.crosslink),
|
||||
hash_tree_root(state.current_crosslinks[shard]) in
|
||||
# TODO pointless memory allocation, etc.
|
||||
@[it.parent_root, hash_tree_root(it)])
|
||||
|
||||
# default=Crosslink()
|
||||
if len(crosslinks) == 0:
|
||||
return (Crosslink(), initSet[ValidatorIndex]())
|
||||
|
||||
## Winning crosslink has the crosslink data root with the most balance voting
|
||||
## for it (ties broken lexicographically)
|
||||
var
|
||||
winning_crosslink: Crosslink
|
||||
winning_crosslink_balance = 0.Gwei
|
||||
|
||||
for candidate_crosslink in crosslinks:
|
||||
## TODO check if should cache this again
|
||||
## let root_balance = get_attesting_balance_cached(
|
||||
## state, attestations_for.getOrDefault(r), cache)
|
||||
let crosslink_balance =
|
||||
get_attesting_balance(
|
||||
state,
|
||||
filterIt(attestations, it.data.crosslink == candidate_crosslink),
|
||||
stateCache)
|
||||
if (crosslink_balance > winning_crosslink_balance or
|
||||
(winning_crosslink_balance == crosslink_balance and
|
||||
lowerThan(winning_crosslink.data_root,
|
||||
candidate_crosslink.data_root))):
|
||||
winning_crosslink = candidate_crosslink
|
||||
winning_crosslink_balance = crosslink_balance
|
||||
|
||||
let winning_attestations =
|
||||
filterIt(attestations, it.data.crosslink == winning_crosslink)
|
||||
(winning_crosslink,
|
||||
get_unslashed_attesting_indices(state, winning_attestations, stateCache))
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#justification-and-finalization
|
||||
func process_justification_and_finalization(
|
||||
state: var BeaconState, stateCache: var StateCache) =
|
||||
if get_current_epoch(state) <= GENESIS_EPOCH + 1:
|
||||
return
|
||||
|
||||
let
|
||||
previous_epoch = get_previous_epoch(state)
|
||||
current_epoch = get_current_epoch(state)
|
||||
old_previous_justified_epoch = state.previous_justified_epoch
|
||||
old_current_justified_epoch = state.current_justified_epoch
|
||||
|
||||
# Process justifications
|
||||
state.previous_justified_epoch = state.current_justified_epoch
|
||||
state.previous_justified_root = state.current_justified_root
|
||||
state.justification_bitfield = (state.justification_bitfield shl 1)
|
||||
let previous_epoch_matching_target_balance =
|
||||
get_attesting_balance(state,
|
||||
get_matching_target_attestations(state, previous_epoch), stateCache)
|
||||
if previous_epoch_matching_target_balance * 3 >=
|
||||
get_total_active_balance(state) * 2:
|
||||
state.current_justified_epoch = previous_epoch
|
||||
state.current_justified_root =
|
||||
get_block_root(state, state.current_justified_epoch)
|
||||
state.justification_bitfield = state.justification_bitfield or (1 shl 1)
|
||||
let current_epoch_matching_target_balance =
|
||||
get_attesting_balance(state,
|
||||
get_matching_target_attestations(state, current_epoch),
|
||||
stateCache)
|
||||
if current_epoch_matching_target_balance * 3 >=
|
||||
get_total_active_balance(state) * 2:
|
||||
state.current_justified_epoch = current_epoch
|
||||
state.current_justified_root =
|
||||
get_block_root(state, state.current_justified_epoch)
|
||||
state.justification_bitfield = state.justification_bitfield or (1 shl 0)
|
||||
|
||||
# Process finalizations
|
||||
let bitfield = state.justification_bitfield
|
||||
|
||||
## The 2nd/3rd/4th most recent epochs are justified, the 2nd using the 4th
|
||||
## as source
|
||||
if (bitfield shr 1) mod 8 == 0b111 and old_previous_justified_epoch + 3 ==
|
||||
current_epoch:
|
||||
state.finalized_epoch = old_previous_justified_epoch
|
||||
state.finalized_root = get_block_root(state, state.finalized_epoch)
|
||||
|
||||
## The 2nd/3rd most recent epochs are justified, the 2nd using the 3rd as
|
||||
## source
|
||||
if (bitfield shr 1) mod 4 == 0b11 and old_previous_justified_epoch + 2 ==
|
||||
current_epoch:
|
||||
state.finalized_epoch = old_previous_justified_epoch
|
||||
state.finalized_root = get_block_root(state, state.finalized_epoch)
|
||||
|
||||
## The 1st/2nd/3rd most recent epochs are justified, the 1st using the 3rd as
|
||||
## source
|
||||
if (bitfield shr 0) mod 8 == 0b111 and old_current_justified_epoch + 2 ==
|
||||
current_epoch:
|
||||
state.finalized_epoch = old_current_justified_epoch
|
||||
state.finalized_root = get_block_root(state, state.finalized_epoch)
|
||||
|
||||
## The 1st/2nd most recent epochs are justified, the 1st using the 2nd as
|
||||
## source
|
||||
if (bitfield shr 0) mod 4 == 0b11 and old_current_justified_epoch + 1 ==
|
||||
current_epoch:
|
||||
state.finalized_epoch = old_current_justified_epoch
|
||||
state.finalized_root = get_block_root(state, state.finalized_epoch)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#crosslinks
|
||||
func process_crosslinks(state: var BeaconState, stateCache: var StateCache) =
|
||||
## TODO is there a semantic reason for this, or is this just a way to force
|
||||
## copying? If so, why not just `list(foo)` or similar? This is strange. In
|
||||
## this case, for type reasons, don't do weird
|
||||
## [c for c in state.current_crosslinks] from spec.
|
||||
state.previous_crosslinks = state.current_crosslinks
|
||||
|
||||
for epoch_int in get_previous_epoch(state).uint64 ..
|
||||
get_current_epoch(state).uint64:
|
||||
# This issue comes up regularly -- iterating means an int type,
|
||||
# which then needs re-conversion back to specialized type.
|
||||
let epoch = epoch_int.Epoch
|
||||
for offset in 0'u64 ..< get_epoch_committee_count(state, epoch):
|
||||
let
|
||||
shard = (get_epoch_start_shard(state, epoch) + offset) mod SHARD_COUNT
|
||||
crosslink_committee =
|
||||
get_crosslink_committee(state, epoch, shard, stateCache)
|
||||
# In general, it'll loop over the same shards twice, and
|
||||
# get_winning_root_and_participants is defined to return
|
||||
# the same results from the previous epoch as current.
|
||||
# TODO cache like before, in 0.5 version of this function
|
||||
(winning_crosslink, attesting_indices) =
|
||||
get_winning_crosslink_and_attesting_indices(
|
||||
state, epoch, shard, stateCache)
|
||||
if 3'u64 * get_total_balance(state, attesting_indices) >=
|
||||
2'u64 * get_total_balance(state, crosslink_committee):
|
||||
state.current_crosslinks[shard] = winning_crosslink
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#rewards-and-penalties-1
|
||||
func get_base_reward(state: BeaconState, index: ValidatorIndex): Gwei =
|
||||
let
|
||||
total_balance = get_total_active_balance(state)
|
||||
effective_balance = state.validator_registry[index].effective_balance
|
||||
effective_balance * BASE_REWARD_FACTOR div
|
||||
integer_squareroot(total_balance) div BASE_REWARDS_PER_EPOCH
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#rewards-and-penalties
|
||||
func get_attestation_deltas(state: BeaconState, stateCache: var StateCache):
|
||||
tuple[a: seq[Gwei], b: seq[Gwei]] =
|
||||
let
|
||||
previous_epoch = get_previous_epoch(state)
|
||||
total_balance = get_total_active_balance(state)
|
||||
var
|
||||
rewards = repeat(0'u64, len(state.validator_registry))
|
||||
penalties = repeat(0'u64, len(state.validator_registry))
|
||||
eligible_validator_indices : seq[ValidatorIndex] = @[]
|
||||
|
||||
for index, v in state.validator_registry:
|
||||
if is_active_validator(v, previous_epoch) or
|
||||
(v.slashed and previous_epoch + 1 < v.withdrawable_epoch):
|
||||
eligible_validator_indices.add index.ValidatorIndex
|
||||
|
||||
# Micro-incentives for matching FFG source, FFG target, and head
|
||||
let
|
||||
matching_source_attestations =
|
||||
get_matching_source_attestations(state, previous_epoch)
|
||||
matching_target_attestations =
|
||||
get_matching_target_attestations(state, previous_epoch)
|
||||
matching_head_attestations =
|
||||
get_matching_head_attestations(state, previous_epoch)
|
||||
for attestations in
|
||||
@[matching_source_attestations, matching_target_attestations,
|
||||
matching_head_attestations]:
|
||||
let
|
||||
unslashed_attesting_indices =
|
||||
get_unslashed_attesting_indices(state, attestations, stateCache)
|
||||
attesting_balance = get_attesting_balance(state, attestations, stateCache)
|
||||
for index in eligible_validator_indices:
|
||||
if index in unslashed_attesting_indices:
|
||||
rewards[index] +=
|
||||
get_base_reward(state, index) * attesting_balance div total_balance
|
||||
else:
|
||||
penalties[index] += get_base_reward(state, index)
|
||||
|
||||
if matching_source_attestations.len == 0:
|
||||
return (rewards, penalties)
|
||||
|
||||
# Proposer and inclusion delay micro-rewards
|
||||
for index in get_unslashed_attesting_indices(
|
||||
state, matching_source_attestations, stateCache):
|
||||
doAssert matching_source_attestations.len > 0
|
||||
var attestation = matching_source_attestations[0]
|
||||
for a in matching_source_attestations:
|
||||
if index notin get_attesting_indices(
|
||||
state, a.data, a.aggregation_bitfield, stateCache):
|
||||
continue
|
||||
if a.inclusion_delay < attestation.inclusion_delay:
|
||||
attestation = a
|
||||
rewards[attestation.proposer_index] += get_base_reward(state, index) div
|
||||
PROPOSER_REWARD_QUOTIENT
|
||||
rewards[index] +=
|
||||
get_base_reward(state, index) * MIN_ATTESTATION_INCLUSION_DELAY div
|
||||
attestation.inclusion_delay
|
||||
|
||||
# Inactivity penalty
|
||||
let finality_delay = previous_epoch - state.finalized_epoch
|
||||
if finality_delay > MIN_EPOCHS_TO_INACTIVITY_PENALTY:
|
||||
let matching_target_attesting_indices =
|
||||
get_unslashed_attesting_indices(
|
||||
state, matching_target_attestations, stateCache)
|
||||
for index in eligible_validator_indices:
|
||||
penalties[index] +=
|
||||
BASE_REWARDS_PER_EPOCH.uint64 * get_base_reward(state, index)
|
||||
if index notin matching_target_attesting_indices:
|
||||
penalties[index] +=
|
||||
state.validator_registry[index].effective_balance *
|
||||
finality_delay div INACTIVITY_PENALTY_QUOTIENT
|
||||
|
||||
(rewards, penalties)
|
||||
|
||||
# TODO re-cache this one, as under 0.5 version, if profiling suggests it
|
||||
func get_crosslink_deltas(state: BeaconState, cache: var StateCache):
|
||||
tuple[a: seq[Gwei], b: seq[Gwei]] =
|
||||
|
||||
var
|
||||
rewards = repeat(0'u64, len(state.validator_registry))
|
||||
penalties = repeat(0'u64, len(state.validator_registry))
|
||||
let epoch = get_previous_epoch(state)
|
||||
for offset in 0'u64 ..< get_epoch_committee_count(state, epoch):
|
||||
let
|
||||
shard = (get_epoch_start_shard(state, epoch) + offset) mod SHARD_COUNT
|
||||
crosslink_committee =
|
||||
get_crosslink_committee(state, epoch, shard, cache)
|
||||
(winning_crosslink, attesting_indices) =
|
||||
get_winning_crosslink_and_attesting_indices(
|
||||
state, epoch, shard, cache)
|
||||
attesting_balance = get_total_balance(state, attesting_indices)
|
||||
committee_balance = get_total_balance(state, crosslink_committee)
|
||||
for index in crosslink_committee:
|
||||
let base_reward = get_base_reward(state, index)
|
||||
if index in attesting_indices:
|
||||
rewards[index] +=
|
||||
get_base_reward(state, index) * attesting_balance div
|
||||
committee_balance
|
||||
else:
|
||||
penalties[index] += get_base_reward(state, index)
|
||||
|
||||
(rewards, penalties)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#rewards-and-penalties-1
|
||||
func process_rewards_and_penalties(
|
||||
state: var BeaconState, cache: var StateCache) =
|
||||
if get_current_epoch(state) == GENESIS_EPOCH:
|
||||
return
|
||||
|
||||
let
|
||||
(rewards1, penalties1) = get_attestation_deltas(state, cache)
|
||||
(rewards2, penalties2) = get_crosslink_deltas(state, cache)
|
||||
for i in 0 ..< len(state.validator_registry):
|
||||
increase_balance(state, i.ValidatorIndex, rewards1[i] + rewards2[i])
|
||||
decrease_balance(state, i.ValidatorIndex, penalties1[i] + penalties2[i])
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#slashings
|
||||
func process_slashings(state: var BeaconState) =
|
||||
let
|
||||
current_epoch = get_current_epoch(state)
|
||||
total_balance = get_total_active_balance(state)
|
||||
|
||||
# Compute `total_penalties`
|
||||
total_at_start = state.latest_slashed_balances[
|
||||
(current_epoch + 1) mod LATEST_SLASHED_EXIT_LENGTH]
|
||||
total_at_end =
|
||||
state.latest_slashed_balances[current_epoch mod
|
||||
LATEST_SLASHED_EXIT_LENGTH]
|
||||
total_penalties = total_at_end - total_at_start
|
||||
|
||||
for index, validator in state.validator_registry:
|
||||
if validator.slashed and current_epoch == validator.withdrawable_epoch -
|
||||
LATEST_SLASHED_EXIT_LENGTH div 2:
|
||||
let
|
||||
penalty = max(
|
||||
validator.effective_balance *
|
||||
min(total_penalties * 3, total_balance) div total_balance,
|
||||
validator.effective_balance div MIN_SLASHING_PENALTY_QUOTIENT)
|
||||
decrease_balance(state, index.ValidatorIndex, penalty)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#final-updates
|
||||
func process_final_updates(state: var BeaconState) =
|
||||
let
|
||||
current_epoch = get_current_epoch(state)
|
||||
next_epoch = current_epoch + 1
|
||||
|
||||
# Reset eth1 data votes
|
||||
if (state.slot + 1) mod SLOTS_PER_ETH1_VOTING_PERIOD == 0:
|
||||
state.eth1_data_votes = @[]
|
||||
|
||||
# Update effective balances with hysteresis
|
||||
for index, validator in state.validator_registry:
|
||||
let balance = state.balances[index]
|
||||
const HALF_INCREMENT = EFFECTIVE_BALANCE_INCREMENT div 2
|
||||
if balance < validator.effective_balance or
|
||||
validator.effective_balance + 3'u64 * HALF_INCREMENT < balance:
|
||||
state.validator_registry[index].effective_balance =
|
||||
min(
|
||||
balance - balance mod EFFECTIVE_BALANCE_INCREMENT,
|
||||
MAX_EFFECTIVE_BALANCE)
|
||||
|
||||
# Update start shard
|
||||
state.latest_start_shard =
|
||||
(state.latest_start_shard + get_shard_delta(state, current_epoch)) mod
|
||||
SHARD_COUNT
|
||||
|
||||
# Set total slashed balances
|
||||
state.latest_slashed_balances[next_epoch mod LATEST_SLASHED_EXIT_LENGTH] = (
|
||||
state.latest_slashed_balances[current_epoch mod LATEST_SLASHED_EXIT_LENGTH]
|
||||
)
|
||||
|
||||
# Set randao mix
|
||||
state.latest_randao_mixes[next_epoch mod LATEST_RANDAO_MIXES_LENGTH] =
|
||||
get_randao_mix(state, current_epoch)
|
||||
|
||||
# Set historical root accumulator
|
||||
if next_epoch mod (SLOTS_PER_HISTORICAL_ROOT div SLOTS_PER_EPOCH).uint64 == 0:
|
||||
let historical_batch = HistoricalBatch(
|
||||
block_roots: state.latest_block_roots,
|
||||
state_roots: state.latest_state_roots,
|
||||
)
|
||||
state.historical_roots.add (hash_tree_root(historical_batch))
|
||||
|
||||
# Rotate current/previous epoch attestations
|
||||
state.previous_epoch_attestations = state.current_epoch_attestations
|
||||
state.current_epoch_attestations = @[]
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#per-epoch-processing
|
||||
func processEpoch*(state: var BeaconState) =
|
||||
if not (state.slot > GENESIS_SLOT and
|
||||
(state.slot + 1) mod SLOTS_PER_EPOCH == 0):
|
||||
return
|
||||
|
||||
var per_epoch_cache = get_empty_per_epoch_cache()
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#justification-and-finalization
|
||||
process_justification_and_finalization(state, per_epoch_cache)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#crosslinks
|
||||
process_crosslinks(state, per_epoch_cache)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#rewards-and-penalties-1
|
||||
process_rewards_and_penalties(state, per_epoch_cache)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#registry-updates
|
||||
# Don't rely on caching here.
|
||||
process_registry_updates(state)
|
||||
|
||||
## Caching here for get_crosslink_committee(...) can break otherwise, since
|
||||
## get_active_validator_indices(...) usually changes.
|
||||
clear(per_epoch_cache.crosslink_committee_cache)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#slashings
|
||||
process_slashings(state)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#final-updates
|
||||
process_final_updates(state)
|
||||
|
|
@ -33,384 +33,8 @@
|
|||
import
|
||||
algorithm, collections/sets, chronicles, math, options, sequtils, sets, tables,
|
||||
./extras, ./ssz, ./beacon_node_types,
|
||||
./spec/[beaconstate, bitfield, crypto, datatypes, digest, helpers, validator]
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#block-header
|
||||
proc processBlockHeader(
|
||||
state: var BeaconState, blck: BeaconBlock, flags: UpdateFlags,
|
||||
stateCache: var StateCache): bool =
|
||||
# Verify that the slots match
|
||||
if not (blck.slot == state.slot):
|
||||
notice "Block header: slot mismatch",
|
||||
block_slot = humaneSlotNum(blck.slot),
|
||||
state_slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
# Verify that the parent matches
|
||||
if skipValidation notin flags and not (blck.parent_root ==
|
||||
signing_root(state.latest_block_header)):
|
||||
notice "Block header: previous block root mismatch",
|
||||
latest_block_header = state.latest_block_header,
|
||||
blck = shortLog(blck),
|
||||
latest_block_header_root = shortLog(signing_root(state.latest_block_header))
|
||||
return false
|
||||
|
||||
# Save current block as the new latest block
|
||||
state.latest_block_header = BeaconBlockHeader(
|
||||
slot: blck.slot,
|
||||
parent_root: blck.parent_root,
|
||||
body_root: hash_tree_root(blck.body),
|
||||
)
|
||||
|
||||
# Verify proposer is not slashed
|
||||
let proposer =
|
||||
state.validator_registry[get_beacon_proposer_index(state, stateCache)]
|
||||
if proposer.slashed:
|
||||
notice "Block header: proposer slashed"
|
||||
return false
|
||||
|
||||
# Verify proposer signature
|
||||
if skipValidation notin flags and not bls_verify(
|
||||
proposer.pubkey,
|
||||
signing_root(blck).data,
|
||||
blck.signature,
|
||||
get_domain(state, DOMAIN_BEACON_PROPOSER)):
|
||||
notice "Block header: invalid block header",
|
||||
proposer_pubkey = proposer.pubkey,
|
||||
block_root = shortLog(signing_root(blck)),
|
||||
block_signature = blck.signature
|
||||
return false
|
||||
|
||||
true
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#randao
|
||||
proc processRandao(
|
||||
state: var BeaconState, body: BeaconBlockBody, flags: UpdateFlags,
|
||||
stateCache: var StateCache): bool =
|
||||
let
|
||||
proposer_index = get_beacon_proposer_index(state, stateCache)
|
||||
proposer = addr state.validator_registry[proposer_index]
|
||||
|
||||
# Verify that the provided randao value is valid
|
||||
if skipValidation notin flags:
|
||||
if not bls_verify(
|
||||
proposer.pubkey,
|
||||
hash_tree_root(get_current_epoch(state).uint64).data,
|
||||
body.randao_reveal,
|
||||
get_domain(state, DOMAIN_RANDAO)):
|
||||
|
||||
notice "Randao mismatch", proposer_pubkey = proposer.pubkey,
|
||||
message = get_current_epoch(state),
|
||||
signature = body.randao_reveal,
|
||||
slot = state.slot
|
||||
return false
|
||||
|
||||
# Mix it in
|
||||
let
|
||||
mix = get_current_epoch(state) mod LATEST_RANDAO_MIXES_LENGTH
|
||||
rr = eth2hash(body.randao_reveal.getBytes()).data
|
||||
|
||||
for i, b in state.latest_randao_mixes[mix].data:
|
||||
state.latest_randao_mixes[mix].data[i] = b xor rr[i]
|
||||
|
||||
true
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#eth1-data
|
||||
func processEth1Data(state: var BeaconState, body: BeaconBlockBody) =
|
||||
state.eth1_data_votes.add body.eth1_data
|
||||
if state.eth1_data_votes.count(body.eth1_data) * 2 >
|
||||
SLOTS_PER_ETH1_VOTING_PERIOD:
|
||||
state.latest_eth1_data = body.eth1_data
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#is_slashable_validator
|
||||
func is_slashable_validator(validator: Validator, epoch: Epoch): bool =
|
||||
# Check if ``validator`` is slashable.
|
||||
(not validator.slashed) and
|
||||
(validator.activation_epoch <= epoch) and
|
||||
(epoch < validator.withdrawable_epoch)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#proposer-slashings
|
||||
proc processProposerSlashings(
|
||||
state: var BeaconState, blck: BeaconBlock, flags: UpdateFlags,
|
||||
stateCache: var StateCache): bool =
|
||||
if len(blck.body.proposer_slashings) > MAX_PROPOSER_SLASHINGS:
|
||||
notice "PropSlash: too many!",
|
||||
proposer_slashings = len(blck.body.proposer_slashings)
|
||||
return false
|
||||
|
||||
for proposer_slashing in blck.body.proposer_slashings:
|
||||
let proposer = state.validator_registry[proposer_slashing.proposer_index.int]
|
||||
|
||||
# Verify that the epoch is the same
|
||||
if not (slot_to_epoch(proposer_slashing.header_1.slot) ==
|
||||
slot_to_epoch(proposer_slashing.header_2.slot)):
|
||||
notice "PropSlash: epoch mismatch"
|
||||
return false
|
||||
|
||||
# But the headers are different
|
||||
if not (proposer_slashing.header_1 != proposer_slashing.header_2):
|
||||
notice "PropSlash: headers not different"
|
||||
return false
|
||||
|
||||
# Check proposer is slashable
|
||||
if not is_slashable_validator(proposer, get_current_epoch(state)):
|
||||
notice "PropSlash: slashed proposer"
|
||||
return false
|
||||
|
||||
# Signatures are valid
|
||||
if skipValidation notin flags:
|
||||
for i, header in @[proposer_slashing.header_1, proposer_slashing.header_2]:
|
||||
if not bls_verify(
|
||||
proposer.pubkey,
|
||||
signing_root(header).data,
|
||||
header.signature,
|
||||
get_domain(
|
||||
state, DOMAIN_BEACON_PROPOSER, slot_to_epoch(header.slot))):
|
||||
notice "PropSlash: invalid signature",
|
||||
signature_index = i
|
||||
return false
|
||||
|
||||
slashValidator(
|
||||
state, proposer_slashing.proposer_index.ValidatorIndex, stateCache)
|
||||
|
||||
true
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#is_slashable_attestation_data
|
||||
func is_slashable_attestation_data(
|
||||
data_1: AttestationData, data_2: AttestationData): bool =
|
||||
## Check if ``data_1`` and ``data_2`` are slashable according to Casper FFG
|
||||
## rules.
|
||||
|
||||
# Double vote
|
||||
(data_1 != data_2 and data_1.target_epoch == data_2.target_epoch) or
|
||||
# Surround vote
|
||||
(data_1.source_epoch < data_2.source_epoch and
|
||||
data_2.target_epoch < data_1.target_epoch)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#attester-slashings
|
||||
proc processAttesterSlashings(state: var BeaconState, blck: BeaconBlock,
|
||||
stateCache: var StateCache): bool =
|
||||
# Process ``AttesterSlashing`` operation.
|
||||
if len(blck.body.attester_slashings) > MAX_ATTESTER_SLASHINGS:
|
||||
notice "CaspSlash: too many!"
|
||||
return false
|
||||
|
||||
result = true
|
||||
for attester_slashing in blck.body.attester_slashings:
|
||||
let
|
||||
attestation_1 = attester_slashing.attestation_1
|
||||
attestation_2 = attester_slashing.attestation_2
|
||||
|
||||
if not is_slashable_attestation_data(
|
||||
attestation_1.data, attestation_2.data):
|
||||
notice "CaspSlash: surround or double vote check failed"
|
||||
return false
|
||||
|
||||
if not validate_indexed_attestation(state, attestation_1):
|
||||
notice "CaspSlash: invalid votes 1"
|
||||
return false
|
||||
|
||||
if not validate_indexed_attestation(state, attestation_2):
|
||||
notice "CaspSlash: invalid votes 2"
|
||||
return false
|
||||
|
||||
var slashed_any = false
|
||||
|
||||
## TODO there's a lot of sorting/set construction here and
|
||||
## verify_indexed_attestation, but go by spec unless there
|
||||
## is compelling perf evidence otherwise.
|
||||
let attesting_indices_1 =
|
||||
attestation_1.custody_bit_0_indices & attestation_1.custody_bit_1_indices
|
||||
let attesting_indices_2 =
|
||||
attestation_2.custody_bit_0_indices & attestation_2.custody_bit_1_indices
|
||||
for index in sorted(toSeq(intersection(toSet(attesting_indices_1),
|
||||
toSet(attesting_indices_2)).items), system.cmp):
|
||||
if is_slashable_validator(state.validator_registry[index.int],
|
||||
get_current_epoch(state)):
|
||||
slash_validator(state, index.ValidatorIndex, stateCache)
|
||||
slashed_any = true
|
||||
result = result and slashed_any
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#attestations
|
||||
proc processAttestations(
|
||||
state: var BeaconState, blck: BeaconBlock, flags: UpdateFlags,
|
||||
stateCache: var StateCache): bool =
|
||||
## Each block includes a number of attestations that the proposer chose. Each
|
||||
## attestation represents an update to a specific shard and is signed by a
|
||||
## committee of validators.
|
||||
## Here we make sanity checks for each attestation and it to the state - most
|
||||
## updates will happen at the epoch boundary where state updates happen in
|
||||
## bulk.
|
||||
if blck.body.attestations.len > MAX_ATTESTATIONS:
|
||||
notice "Attestation: too many!", attestations = blck.body.attestations.len
|
||||
return false
|
||||
|
||||
if not blck.body.attestations.allIt(checkAttestation(state, it, flags, stateCache)):
|
||||
return false
|
||||
|
||||
# All checks passed - update state
|
||||
# Apply the attestations
|
||||
var committee_count_cache = initTable[Epoch, uint64]()
|
||||
|
||||
for attestation in blck.body.attestations:
|
||||
# Caching
|
||||
let
|
||||
epoch = attestation.data.target_epoch
|
||||
committee_count = if epoch in committee_count_cache:
|
||||
committee_count_cache[epoch]
|
||||
else:
|
||||
get_epoch_committee_count(state, epoch)
|
||||
committee_count_cache[epoch] = committee_count
|
||||
|
||||
# Spec content
|
||||
let attestation_slot =
|
||||
get_attestation_data_slot(state, attestation.data, committee_count)
|
||||
let pending_attestation = PendingAttestation(
|
||||
data: attestation.data,
|
||||
aggregation_bitfield: attestation.aggregation_bitfield,
|
||||
inclusion_delay: state.slot - attestation_slot,
|
||||
proposer_index: get_beacon_proposer_index(state, stateCache),
|
||||
)
|
||||
|
||||
if attestation.data.target_epoch == get_current_epoch(state):
|
||||
state.current_epoch_attestations.add(pending_attestation)
|
||||
else:
|
||||
state.previous_epoch_attestations.add(pending_attestation)
|
||||
|
||||
true
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.5.1/specs/core/0_beacon-chain.md#deposits
|
||||
proc processDeposits(state: var BeaconState, blck: BeaconBlock): bool =
|
||||
if not (len(blck.body.deposits) <= MAX_DEPOSITS):
|
||||
notice "processDeposits: too many deposits"
|
||||
return false
|
||||
|
||||
for deposit in blck.body.deposits:
|
||||
if not process_deposit(state, deposit):
|
||||
notice "processDeposits: deposit invalid"
|
||||
return false
|
||||
|
||||
true
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#voluntary-exits
|
||||
proc processVoluntaryExits(
|
||||
state: var BeaconState, blck: BeaconBlock, flags: UpdateFlags): bool =
|
||||
# Process ``VoluntaryExit`` transaction.
|
||||
if len(blck.body.voluntary_exits) > MAX_VOLUNTARY_EXITS:
|
||||
notice "Exit: too many!"
|
||||
return false
|
||||
|
||||
for exit in blck.body.voluntary_exits:
|
||||
let validator = state.validator_registry[exit.validator_index.int]
|
||||
|
||||
# Verify the validator is active
|
||||
if not is_active_validator(validator, get_current_epoch(state)):
|
||||
notice "Exit: validator not active"
|
||||
return false
|
||||
|
||||
# Verify the validator has not yet exited
|
||||
if not (validator.exit_epoch == FAR_FUTURE_EPOCH):
|
||||
notice "Exit: validator has exited"
|
||||
return false
|
||||
|
||||
## Exits must specify an epoch when they become valid; they are not valid
|
||||
## before then
|
||||
if not (get_current_epoch(state) >= exit.epoch):
|
||||
notice "Exit: exit epoch not passed"
|
||||
return false
|
||||
|
||||
# Verify the validator has been active long enough
|
||||
# TODO detect underflow
|
||||
if not (get_current_epoch(state) - validator.activation_epoch >=
|
||||
PERSISTENT_COMMITTEE_PERIOD):
|
||||
notice "Exit: not in validator set long enough"
|
||||
return false
|
||||
|
||||
# Verify signature
|
||||
if skipValidation notin flags:
|
||||
if not bls_verify(
|
||||
validator.pubkey, signing_root(exit).data, exit.signature,
|
||||
get_domain(state, DOMAIN_VOLUNTARY_EXIT, exit.epoch)):
|
||||
notice "Exit: invalid signature"
|
||||
return false
|
||||
|
||||
# Initiate exit
|
||||
initiate_validator_exit(state, exit.validator_index.ValidatorIndex)
|
||||
|
||||
true
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#transfers
|
||||
proc processTransfers(state: var BeaconState, blck: BeaconBlock,
|
||||
flags: UpdateFlags, stateCache: var StateCache): bool =
|
||||
if not (len(blck.body.transfers) <= MAX_TRANSFERS):
|
||||
notice "Transfer: too many transfers"
|
||||
return false
|
||||
|
||||
for transfer in blck.body.transfers:
|
||||
let sender_balance = state.balances[transfer.sender.int]
|
||||
|
||||
## Verify the amount and fee are not individually too big (for anti-overflow
|
||||
## purposes)
|
||||
if not (sender_balance >= max(transfer.amount, transfer.fee)):
|
||||
notice "Transfer: sender balance too low for transfer amount or fee"
|
||||
return false
|
||||
|
||||
# A transfer is valid in only one slot
|
||||
if not (state.slot == transfer.slot):
|
||||
notice "Transfer: slot mismatch"
|
||||
return false
|
||||
|
||||
## Sender must be not yet eligible for activation, withdrawn, or transfer
|
||||
## balance over MAX_EFFECTIVE_BALANCE
|
||||
if not (
|
||||
state.validator_registry[transfer.sender.int].activation_epoch ==
|
||||
FAR_FUTURE_EPOCH or
|
||||
get_current_epoch(state) >=
|
||||
state.validator_registry[
|
||||
transfer.sender.int].withdrawable_epoch or
|
||||
transfer.amount + transfer.fee + MAX_EFFECTIVE_BALANCE <=
|
||||
state.balances[transfer.sender.int]):
|
||||
notice "Transfer: only withdrawn or not-activated accounts with sufficient balance can transfer"
|
||||
return false
|
||||
|
||||
# Verify that the pubkey is valid
|
||||
let wc = state.validator_registry[transfer.sender.int].
|
||||
withdrawal_credentials
|
||||
if not (wc.data[0] == BLS_WITHDRAWAL_PREFIX and
|
||||
wc.data[1..^1] == eth2hash(transfer.pubkey.getBytes).data[1..^1]):
|
||||
notice "Transfer: incorrect withdrawal credentials"
|
||||
return false
|
||||
|
||||
# Verify that the signature is valid
|
||||
if skipValidation notin flags:
|
||||
if not bls_verify(
|
||||
transfer.pubkey, signing_root(transfer).data, transfer.signature,
|
||||
get_domain(state, DOMAIN_TRANSFER)):
|
||||
notice "Transfer: incorrect signature"
|
||||
return false
|
||||
|
||||
# Process the transfer
|
||||
decrease_balance(
|
||||
state, transfer.sender.ValidatorIndex, transfer.amount + transfer.fee)
|
||||
increase_balance(
|
||||
state, transfer.recipient.ValidatorIndex, transfer.amount)
|
||||
increase_balance(
|
||||
state, get_beacon_proposer_index(state, stateCache), transfer.fee)
|
||||
|
||||
# Verify balances are not dust
|
||||
if not (
|
||||
0'u64 < state.balances[transfer.sender.int] and
|
||||
state.balances[transfer.sender.int] < MIN_DEPOSIT_AMOUNT):
|
||||
notice "Transfer: sender balance too low for transfer amount or fee"
|
||||
return false
|
||||
|
||||
if not (
|
||||
0'u64 < state.balances[transfer.recipient.int] and
|
||||
state.balances[transfer.recipient.int] < MIN_DEPOSIT_AMOUNT):
|
||||
notice "Transfer: sender balance too low for transfer amount or fee"
|
||||
return false
|
||||
|
||||
true
|
||||
./spec/[beaconstate, bitfield, crypto, datatypes, digest, helpers, validator],
|
||||
./spec/[state_transition_block, state_transition_epoch]
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#per-slot-processing
|
||||
func advance_slot(state: var BeaconState) =
|
||||
|
|
@ -436,475 +60,6 @@ func process_slot(state: var BeaconState) =
|
|||
state.latest_block_roots[state.slot mod SLOTS_PER_HISTORICAL_ROOT] =
|
||||
signing_root(state.latest_block_header)
|
||||
|
||||
proc processBlock(
|
||||
state: var BeaconState, blck: BeaconBlock, flags: UpdateFlags,
|
||||
stateCache: var StateCache): bool =
|
||||
## When there's a new block, we need to verify that the block is sane and
|
||||
## update the state accordingly
|
||||
|
||||
# TODO when there's a failure, we should reset the state!
|
||||
# TODO probably better to do all verification first, then apply state changes
|
||||
|
||||
if not processBlockHeader(state, blck, flags, stateCache):
|
||||
notice "Block header not valid", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
if not processRandao(state, blck.body, flags, stateCache):
|
||||
debug "[Block processing] Randao failure", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
processEth1Data(state, blck.body)
|
||||
|
||||
if not processProposerSlashings(state, blck, flags, stateCache):
|
||||
debug "[Block processing] Proposer slashing failure", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
if not processAttesterSlashings(state, blck, stateCache):
|
||||
debug "[Block processing] Attester slashing failure", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
if not processAttestations(state, blck, flags, stateCache):
|
||||
debug "[Block processing] Attestation processing failure", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
if not processDeposits(state, blck):
|
||||
debug "[Block processing] Deposit processing failure", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
if not processVoluntaryExits(state, blck, flags):
|
||||
debug "[Block processing] Exit processing failure", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
if not processTransfers(state, blck, flags, stateCache):
|
||||
debug "[Block processing] Transfer processing failure", slot = humaneSlotNum(state.slot)
|
||||
return false
|
||||
|
||||
true
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#helper-functions-1
|
||||
func get_total_active_balance(state: BeaconState): Gwei =
|
||||
return get_total_balance(
|
||||
state,
|
||||
get_active_validator_indices(state, get_current_epoch(state)))
|
||||
|
||||
func get_matching_source_attestations(state: BeaconState, epoch: Epoch):
|
||||
seq[PendingAttestation] =
|
||||
doAssert epoch in @[get_current_epoch(state), get_previous_epoch(state)]
|
||||
if epoch == get_current_epoch(state):
|
||||
state.current_epoch_attestations
|
||||
else:
|
||||
state.previous_epoch_attestations
|
||||
|
||||
func get_matching_target_attestations(state: BeaconState, epoch: Epoch):
|
||||
seq[PendingAttestation] =
|
||||
filterIt(
|
||||
get_matching_source_attestations(state, epoch),
|
||||
it.data.target_root == get_block_root(state, epoch)
|
||||
)
|
||||
|
||||
func get_matching_head_attestations(state: BeaconState, epoch: Epoch):
|
||||
seq[PendingAttestation] =
|
||||
filterIt(
|
||||
get_matching_source_attestations(state, epoch),
|
||||
it.data.beacon_block_root ==
|
||||
get_block_root_at_slot(state, get_attestation_data_slot(state, it.data))
|
||||
)
|
||||
|
||||
func get_unslashed_attesting_indices(
|
||||
state: BeaconState, attestations: seq[PendingAttestation],
|
||||
stateCache: var StateCache): HashSet[ValidatorIndex] =
|
||||
result = initSet[ValidatorIndex]()
|
||||
for a in attestations:
|
||||
result = result.union(get_attesting_indices(
|
||||
state, a.data, a.aggregation_bitfield, stateCache))
|
||||
|
||||
for index in result:
|
||||
if state.validator_registry[index].slashed:
|
||||
result.excl index
|
||||
|
||||
func get_attesting_balance(
|
||||
state: BeaconState, attestations: seq[PendingAttestation],
|
||||
stateCache: var StateCache): Gwei =
|
||||
get_total_balance(state, get_unslashed_attesting_indices(
|
||||
state, attestations, stateCache))
|
||||
|
||||
# Not exactly in spec, but for get_winning_crosslink_and_attesting_indices
|
||||
func lowerThan(candidate, current: Eth2Digest): bool =
|
||||
# return true iff candidate is "lower" than current, per spec rule:
|
||||
# "ties broken in favor of lexicographically higher hash
|
||||
for i, v in current.data:
|
||||
if v > candidate.data[i]: return true
|
||||
false
|
||||
|
||||
func get_winning_crosslink_and_attesting_indices(
|
||||
state: BeaconState, epoch: Epoch, shard: Shard,
|
||||
stateCache: var StateCache): tuple[a: Crosslink, b: HashSet[ValidatorIndex]] =
|
||||
let
|
||||
attestations =
|
||||
filterIt(
|
||||
get_matching_source_attestations(state, epoch),
|
||||
it.data.crosslink.shard == shard)
|
||||
# TODO don't keep h_t_r'ing state.current_crosslinks[shard]
|
||||
crosslinks =
|
||||
filterIt(
|
||||
mapIt(attestations, it.data.crosslink),
|
||||
hash_tree_root(state.current_crosslinks[shard]) in
|
||||
# TODO pointless memory allocation, etc.
|
||||
@[it.parent_root, hash_tree_root(it)])
|
||||
|
||||
# default=Crosslink()
|
||||
if len(crosslinks) == 0:
|
||||
return (Crosslink(), initSet[ValidatorIndex]())
|
||||
|
||||
## Winning crosslink has the crosslink data root with the most balance voting
|
||||
## for it (ties broken lexicographically)
|
||||
var
|
||||
winning_crosslink: Crosslink
|
||||
winning_crosslink_balance = 0.Gwei
|
||||
|
||||
for candidate_crosslink in crosslinks:
|
||||
## TODO check if should cache this again
|
||||
## let root_balance = get_attesting_balance_cached(
|
||||
## state, attestations_for.getOrDefault(r), cache)
|
||||
let crosslink_balance =
|
||||
get_attesting_balance(
|
||||
state,
|
||||
filterIt(attestations, it.data.crosslink == candidate_crosslink),
|
||||
stateCache)
|
||||
if (crosslink_balance > winning_crosslink_balance or
|
||||
(winning_crosslink_balance == crosslink_balance and
|
||||
lowerThan(winning_crosslink.data_root,
|
||||
candidate_crosslink.data_root))):
|
||||
winning_crosslink = candidate_crosslink
|
||||
winning_crosslink_balance = crosslink_balance
|
||||
|
||||
let winning_attestations =
|
||||
filterIt(attestations, it.data.crosslink == winning_crosslink)
|
||||
(winning_crosslink,
|
||||
get_unslashed_attesting_indices(state, winning_attestations, stateCache))
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#justification-and-finalization
|
||||
func process_justification_and_finalization(
|
||||
state: var BeaconState, stateCache: var StateCache) =
|
||||
if get_current_epoch(state) <= GENESIS_EPOCH + 1:
|
||||
return
|
||||
|
||||
let
|
||||
previous_epoch = get_previous_epoch(state)
|
||||
current_epoch = get_current_epoch(state)
|
||||
old_previous_justified_epoch = state.previous_justified_epoch
|
||||
old_current_justified_epoch = state.current_justified_epoch
|
||||
|
||||
# Process justifications
|
||||
state.previous_justified_epoch = state.current_justified_epoch
|
||||
state.previous_justified_root = state.current_justified_root
|
||||
state.justification_bitfield = (state.justification_bitfield shl 1)
|
||||
let previous_epoch_matching_target_balance =
|
||||
get_attesting_balance(state,
|
||||
get_matching_target_attestations(state, previous_epoch), stateCache)
|
||||
if previous_epoch_matching_target_balance * 3 >=
|
||||
get_total_active_balance(state) * 2:
|
||||
state.current_justified_epoch = previous_epoch
|
||||
state.current_justified_root =
|
||||
get_block_root(state, state.current_justified_epoch)
|
||||
state.justification_bitfield = state.justification_bitfield or (1 shl 1)
|
||||
let current_epoch_matching_target_balance =
|
||||
get_attesting_balance(state,
|
||||
get_matching_target_attestations(state, current_epoch),
|
||||
stateCache)
|
||||
if current_epoch_matching_target_balance * 3 >=
|
||||
get_total_active_balance(state) * 2:
|
||||
state.current_justified_epoch = current_epoch
|
||||
state.current_justified_root =
|
||||
get_block_root(state, state.current_justified_epoch)
|
||||
state.justification_bitfield = state.justification_bitfield or (1 shl 0)
|
||||
|
||||
# Process finalizations
|
||||
let bitfield = state.justification_bitfield
|
||||
|
||||
## The 2nd/3rd/4th most recent epochs are justified, the 2nd using the 4th
|
||||
## as source
|
||||
if (bitfield shr 1) mod 8 == 0b111 and old_previous_justified_epoch + 3 ==
|
||||
current_epoch:
|
||||
state.finalized_epoch = old_previous_justified_epoch
|
||||
state.finalized_root = get_block_root(state, state.finalized_epoch)
|
||||
|
||||
## The 2nd/3rd most recent epochs are justified, the 2nd using the 3rd as
|
||||
## source
|
||||
if (bitfield shr 1) mod 4 == 0b11 and old_previous_justified_epoch + 2 ==
|
||||
current_epoch:
|
||||
state.finalized_epoch = old_previous_justified_epoch
|
||||
state.finalized_root = get_block_root(state, state.finalized_epoch)
|
||||
|
||||
## The 1st/2nd/3rd most recent epochs are justified, the 1st using the 3rd as
|
||||
## source
|
||||
if (bitfield shr 0) mod 8 == 0b111 and old_current_justified_epoch + 2 ==
|
||||
current_epoch:
|
||||
state.finalized_epoch = old_current_justified_epoch
|
||||
state.finalized_root = get_block_root(state, state.finalized_epoch)
|
||||
|
||||
## The 1st/2nd most recent epochs are justified, the 1st using the 2nd as
|
||||
## source
|
||||
if (bitfield shr 0) mod 4 == 0b11 and old_current_justified_epoch + 1 ==
|
||||
current_epoch:
|
||||
state.finalized_epoch = old_current_justified_epoch
|
||||
state.finalized_root = get_block_root(state, state.finalized_epoch)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#crosslinks
|
||||
func process_crosslinks(state: var BeaconState, stateCache: var StateCache) =
|
||||
## TODO is there a semantic reason for this, or is this just a way to force
|
||||
## copying? If so, why not just `list(foo)` or similar? This is strange. In
|
||||
## this case, for type reasons, don't do weird
|
||||
## [c for c in state.current_crosslinks] from spec.
|
||||
state.previous_crosslinks = state.current_crosslinks
|
||||
|
||||
for epoch_int in get_previous_epoch(state).uint64 ..
|
||||
get_current_epoch(state).uint64:
|
||||
# This issue comes up regularly -- iterating means an int type,
|
||||
# which then needs re-conversion back to specialized type.
|
||||
let epoch = epoch_int.Epoch
|
||||
for offset in 0'u64 ..< get_epoch_committee_count(state, epoch):
|
||||
let
|
||||
shard = (get_epoch_start_shard(state, epoch) + offset) mod SHARD_COUNT
|
||||
crosslink_committee =
|
||||
get_crosslink_committee(state, epoch, shard, stateCache)
|
||||
# In general, it'll loop over the same shards twice, and
|
||||
# get_winning_root_and_participants is defined to return
|
||||
# the same results from the previous epoch as current.
|
||||
# TODO cache like before, in 0.5 version of this function
|
||||
(winning_crosslink, attesting_indices) =
|
||||
get_winning_crosslink_and_attesting_indices(
|
||||
state, epoch, shard, stateCache)
|
||||
if 3'u64 * get_total_balance(state, attesting_indices) >=
|
||||
2'u64 * get_total_balance(state, crosslink_committee):
|
||||
state.current_crosslinks[shard] = winning_crosslink
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#rewards-and-penalties-1
|
||||
func get_base_reward(state: BeaconState, index: ValidatorIndex): Gwei =
|
||||
let
|
||||
total_balance = get_total_active_balance(state)
|
||||
effective_balance = state.validator_registry[index].effective_balance
|
||||
effective_balance * BASE_REWARD_FACTOR div
|
||||
integer_squareroot(total_balance) div BASE_REWARDS_PER_EPOCH
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#rewards-and-penalties
|
||||
func get_attestation_deltas(state: BeaconState, stateCache: var StateCache):
|
||||
tuple[a: seq[Gwei], b: seq[Gwei]] =
|
||||
let
|
||||
previous_epoch = get_previous_epoch(state)
|
||||
total_balance = get_total_active_balance(state)
|
||||
var
|
||||
rewards = repeat(0'u64, len(state.validator_registry))
|
||||
penalties = repeat(0'u64, len(state.validator_registry))
|
||||
eligible_validator_indices : seq[ValidatorIndex] = @[]
|
||||
|
||||
for index, v in state.validator_registry:
|
||||
if is_active_validator(v, previous_epoch) or
|
||||
(v.slashed and previous_epoch + 1 < v.withdrawable_epoch):
|
||||
eligible_validator_indices.add index.ValidatorIndex
|
||||
|
||||
# Micro-incentives for matching FFG source, FFG target, and head
|
||||
let
|
||||
matching_source_attestations =
|
||||
get_matching_source_attestations(state, previous_epoch)
|
||||
matching_target_attestations =
|
||||
get_matching_target_attestations(state, previous_epoch)
|
||||
matching_head_attestations =
|
||||
get_matching_head_attestations(state, previous_epoch)
|
||||
for attestations in
|
||||
@[matching_source_attestations, matching_target_attestations,
|
||||
matching_head_attestations]:
|
||||
let
|
||||
unslashed_attesting_indices =
|
||||
get_unslashed_attesting_indices(state, attestations, stateCache)
|
||||
attesting_balance = get_attesting_balance(state, attestations, stateCache)
|
||||
for index in eligible_validator_indices:
|
||||
if index in unslashed_attesting_indices:
|
||||
rewards[index] +=
|
||||
get_base_reward(state, index) * attesting_balance div total_balance
|
||||
else:
|
||||
penalties[index] += get_base_reward(state, index)
|
||||
|
||||
if matching_source_attestations.len == 0:
|
||||
return (rewards, penalties)
|
||||
|
||||
# Proposer and inclusion delay micro-rewards
|
||||
for index in get_unslashed_attesting_indices(
|
||||
state, matching_source_attestations, stateCache):
|
||||
doAssert matching_source_attestations.len > 0
|
||||
var attestation = matching_source_attestations[0]
|
||||
for a in matching_source_attestations:
|
||||
if index notin get_attesting_indices(
|
||||
state, a.data, a.aggregation_bitfield, stateCache):
|
||||
continue
|
||||
if a.inclusion_delay < attestation.inclusion_delay:
|
||||
attestation = a
|
||||
rewards[attestation.proposer_index] += get_base_reward(state, index) div
|
||||
PROPOSER_REWARD_QUOTIENT
|
||||
rewards[index] +=
|
||||
get_base_reward(state, index) * MIN_ATTESTATION_INCLUSION_DELAY div
|
||||
attestation.inclusion_delay
|
||||
|
||||
# Inactivity penalty
|
||||
let finality_delay = previous_epoch - state.finalized_epoch
|
||||
if finality_delay > MIN_EPOCHS_TO_INACTIVITY_PENALTY:
|
||||
let matching_target_attesting_indices =
|
||||
get_unslashed_attesting_indices(
|
||||
state, matching_target_attestations, stateCache)
|
||||
for index in eligible_validator_indices:
|
||||
penalties[index] +=
|
||||
BASE_REWARDS_PER_EPOCH.uint64 * get_base_reward(state, index)
|
||||
if index notin matching_target_attesting_indices:
|
||||
penalties[index] +=
|
||||
state.validator_registry[index].effective_balance *
|
||||
finality_delay div INACTIVITY_PENALTY_QUOTIENT
|
||||
|
||||
(rewards, penalties)
|
||||
|
||||
# TODO re-cache this one, as under 0.5 version, if profiling suggests it
|
||||
func get_crosslink_deltas(state: BeaconState, cache: var StateCache):
|
||||
tuple[a: seq[Gwei], b: seq[Gwei]] =
|
||||
|
||||
var
|
||||
rewards = repeat(0'u64, len(state.validator_registry))
|
||||
penalties = repeat(0'u64, len(state.validator_registry))
|
||||
let epoch = get_previous_epoch(state)
|
||||
for offset in 0'u64 ..< get_epoch_committee_count(state, epoch):
|
||||
let
|
||||
shard = (get_epoch_start_shard(state, epoch) + offset) mod SHARD_COUNT
|
||||
crosslink_committee =
|
||||
get_crosslink_committee(state, epoch, shard, cache)
|
||||
(winning_crosslink, attesting_indices) =
|
||||
get_winning_crosslink_and_attesting_indices(
|
||||
state, epoch, shard, cache)
|
||||
attesting_balance = get_total_balance(state, attesting_indices)
|
||||
committee_balance = get_total_balance(state, crosslink_committee)
|
||||
for index in crosslink_committee:
|
||||
let base_reward = get_base_reward(state, index)
|
||||
if index in attesting_indices:
|
||||
rewards[index] +=
|
||||
get_base_reward(state, index) * attesting_balance div
|
||||
committee_balance
|
||||
else:
|
||||
penalties[index] += get_base_reward(state, index)
|
||||
|
||||
(rewards, penalties)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#rewards-and-penalties-1
|
||||
func process_rewards_and_penalties(
|
||||
state: var BeaconState, cache: var StateCache) =
|
||||
if get_current_epoch(state) == GENESIS_EPOCH:
|
||||
return
|
||||
|
||||
let
|
||||
(rewards1, penalties1) = get_attestation_deltas(state, cache)
|
||||
(rewards2, penalties2) = get_crosslink_deltas(state, cache)
|
||||
for i in 0 ..< len(state.validator_registry):
|
||||
increase_balance(state, i.ValidatorIndex, rewards1[i] + rewards2[i])
|
||||
decrease_balance(state, i.ValidatorIndex, penalties1[i] + penalties2[i])
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#slashings
|
||||
func process_slashings(state: var BeaconState) =
|
||||
let
|
||||
current_epoch = get_current_epoch(state)
|
||||
total_balance = get_total_active_balance(state)
|
||||
|
||||
# Compute `total_penalties`
|
||||
total_at_start = state.latest_slashed_balances[
|
||||
(current_epoch + 1) mod LATEST_SLASHED_EXIT_LENGTH]
|
||||
total_at_end =
|
||||
state.latest_slashed_balances[current_epoch mod
|
||||
LATEST_SLASHED_EXIT_LENGTH]
|
||||
total_penalties = total_at_end - total_at_start
|
||||
|
||||
for index, validator in state.validator_registry:
|
||||
if validator.slashed and current_epoch == validator.withdrawable_epoch -
|
||||
LATEST_SLASHED_EXIT_LENGTH div 2:
|
||||
let
|
||||
penalty = max(
|
||||
validator.effective_balance *
|
||||
min(total_penalties * 3, total_balance) div total_balance,
|
||||
validator.effective_balance div MIN_SLASHING_PENALTY_QUOTIENT)
|
||||
decrease_balance(state, index.ValidatorIndex, penalty)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#final-updates
|
||||
func process_final_updates(state: var BeaconState) =
|
||||
let
|
||||
current_epoch = get_current_epoch(state)
|
||||
next_epoch = current_epoch + 1
|
||||
|
||||
# Reset eth1 data votes
|
||||
if (state.slot + 1) mod SLOTS_PER_ETH1_VOTING_PERIOD == 0:
|
||||
state.eth1_data_votes = @[]
|
||||
|
||||
# Update effective balances with hysteresis
|
||||
for index, validator in state.validator_registry:
|
||||
let balance = state.balances[index]
|
||||
const HALF_INCREMENT = EFFECTIVE_BALANCE_INCREMENT div 2
|
||||
if balance < validator.effective_balance or
|
||||
validator.effective_balance + 3'u64 * HALF_INCREMENT < balance:
|
||||
state.validator_registry[index].effective_balance =
|
||||
min(
|
||||
balance - balance mod EFFECTIVE_BALANCE_INCREMENT,
|
||||
MAX_EFFECTIVE_BALANCE)
|
||||
|
||||
# Update start shard
|
||||
state.latest_start_shard =
|
||||
(state.latest_start_shard + get_shard_delta(state, current_epoch)) mod
|
||||
SHARD_COUNT
|
||||
|
||||
# Set total slashed balances
|
||||
state.latest_slashed_balances[next_epoch mod LATEST_SLASHED_EXIT_LENGTH] = (
|
||||
state.latest_slashed_balances[current_epoch mod LATEST_SLASHED_EXIT_LENGTH]
|
||||
)
|
||||
|
||||
# Set randao mix
|
||||
state.latest_randao_mixes[next_epoch mod LATEST_RANDAO_MIXES_LENGTH] =
|
||||
get_randao_mix(state, current_epoch)
|
||||
|
||||
# Set historical root accumulator
|
||||
if next_epoch mod (SLOTS_PER_HISTORICAL_ROOT div SLOTS_PER_EPOCH).uint64 == 0:
|
||||
let historical_batch = HistoricalBatch(
|
||||
block_roots: state.latest_block_roots,
|
||||
state_roots: state.latest_state_roots,
|
||||
)
|
||||
state.historical_roots.add (hash_tree_root(historical_batch))
|
||||
|
||||
# Rotate current/previous epoch attestations
|
||||
state.previous_epoch_attestations = state.current_epoch_attestations
|
||||
state.current_epoch_attestations = @[]
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#per-epoch-processing
|
||||
func processEpoch(state: var BeaconState) =
|
||||
if not (state.slot > GENESIS_SLOT and
|
||||
(state.slot + 1) mod SLOTS_PER_EPOCH == 0):
|
||||
return
|
||||
|
||||
var per_epoch_cache = get_empty_per_epoch_cache()
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#justification-and-finalization
|
||||
process_justification_and_finalization(state, per_epoch_cache)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#crosslinks
|
||||
process_crosslinks(state, per_epoch_cache)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#rewards-and-penalties-1
|
||||
process_rewards_and_penalties(state, per_epoch_cache)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#registry-updates
|
||||
# Don't rely on caching here.
|
||||
process_registry_updates(state)
|
||||
|
||||
## Caching here for get_crosslink_committee(...) can break otherwise, since
|
||||
## get_active_validator_indices(...) usually changes.
|
||||
clear(per_epoch_cache.crosslink_committee_cache)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#slashings
|
||||
process_slashings(state)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.7.1/specs/core/0_beacon-chain.md#final-updates
|
||||
process_final_updates(state)
|
||||
|
||||
# https://github.com/ethereum/eth2.0-specs/blob/v0.6.3/specs/core/0_beacon-chain.md#state-root-verification
|
||||
proc verifyStateRoot(state: BeaconState, blck: BeaconBlock): bool =
|
||||
let state_root = hash_tree_root(state)
|
||||
|
|
|
|||
Loading…
Reference in New Issue