status-im
/
eth2.0-specs
mirror of https://github.com/status-im/eth2.0-specs.git
2
0
Fork 0
Code Issues Projects Releases Wiki Activity

add beaconblockheader and body

This commit is contained in:
Danny Ryan 2018-12-06 17:51:01 -06:00
parent 39f0030fa2
commit 7f542ca714
No known key found for this signature in database
GPG Key ID: 2765A792E42CE07A
1 changed files with 51 additions and 39 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

90
specs/core/0_beacon-chain.md
View File

@ -24,6 +24,8 @@
- [Deposits](#deposits) - [Deposits](#deposits)
- [`DepositParametersRecord`](#depositparametersrecord) - [`DepositParametersRecord`](#depositparametersrecord)
- [Beacon chain blocks](#beacon-chain-blocks) - [Beacon chain blocks](#beacon-chain-blocks)
- [`BeaconBlockHeader`](#beaconblock)
- [`BeaconBlockBody`](#beaconblock)
- [`BeaconBlock`](#beaconblock) - [`BeaconBlock`](#beaconblock)
- [`AttestationRecord`](#attestationrecord) - [`AttestationRecord`](#attestationrecord)
- [`AttestationData`](#attestationdata) - [`AttestationData`](#attestationdata)
@ -244,27 +246,37 @@ Unless otherwise indicated, code appearing in `this style` is to be interpreted
### Beacon chain blocks ### Beacon chain blocks
#### `BeaconBlockHeader`
```python
{
'slot': 'uint64',
# Skip list of ancestor beacon block hashes
# i'th item is the most recent ancestor whose slot is a multiple of 2**i for i = 0, ..., 31
'ancestor_hashes': ['hash32'],
'state_root': 'hash32',
'randao_reveal': 'hash32',
'deposit_receipt_root': 'hash32',
'candidate_pow_receipt_root': 'hash32',
'signature': ['uint384'],
}
```
#### `BeaconBlockBody`
```python
{
'attestations': [AttestationRecord],
'specials': [SpecialRecord],
}
```
#### `BeaconBlock` #### `BeaconBlock`
```python ```python
{ {
# Slot number 'header': BeaconBlockHeader,
'slot': 'uint64', 'body': BeaconBlockBody,
# Proposer RANDAO reveal
'randao_reveal': 'hash32',
# Candidate PoW receipt root
'candidate_pow_receipt_root': 'hash32',
# Skip list of ancestor beacon block hashes
# i'th item is the most recent ancestor whose slot is a multiple of 2**i for i = 0, ..., 31
'ancestor_hashes': ['hash32'],
# State root
'state_root': 'hash32',
# Attestations
'attestations': [AttestationRecord],
# Specials (e.g. exits, penalties)
'specials': [SpecialRecord],
# Proposer signature
'proposer_signature': ['uint384'],
} }
``` ```
@ -637,10 +649,10 @@ Processing the beacon chain is similar to processing the Ethereum 1.0 chain. Cli
For a beacon chain block, `block`, to be processed by a node, the following conditions must be met: For a beacon chain block, `block`, to be processed by a node, the following conditions must be met:
* The parent block with hash `block.ancestor_hashes[0]` has been processed and accepted. * The parent block with hash `block.header.ancestor_hashes[0]` has been processed and accepted.
* The node has processed its `state` up to slot, `block.slot - 1`. * The node has processed its `state` up to slot, `block.header.slot - 1`.
* The Ethereum 1.0 block pointed to by the `state.processed_pow_receipt_root` has been processed and accepted. * The Ethereum 1.0 block pointed to by the `state.processed_pow_receipt_root` has been processed and accepted.
* The node's local clock time is greater than or equal to `state.genesis_time + block.slot * SLOT_DURATION`. * The node's local clock time is greater than or equal to `state.genesis_time + block.header.slot * SLOT_DURATION`.
If these conditions are not met, the client should delay processing the beacon block until the conditions are all satisfied. If these conditions are not met, the client should delay processing the beacon block until the conditions are all satisfied.
@ -653,7 +665,7 @@ The beacon chain fork choice rule is a hybrid that combines justification and fi
* Let `store` be the set of attestations and blocks that the [validator](#dfn-validator) `v` has observed and verified (in particular, block ancestors must be recursively verified). Attestations not part of any chain are still included in `store`. * Let `store` be the set of attestations and blocks that the [validator](#dfn-validator) `v` has observed and verified (in particular, block ancestors must be recursively verified). Attestations not part of any chain are still included in `store`.
* Let `finalized_head` be the finalized block with the highest slot number. (A block `B` is finalized if there is a descendant of `B` in `store` the processing of which sets `B` as finalized.) * Let `finalized_head` be the finalized block with the highest slot number. (A block `B` is finalized if there is a descendant of `B` in `store` the processing of which sets `B` as finalized.)
* Let `justified_head` be the descendant of `finalized_head` with the highest slot number that has been justified for at least `EPOCH_LENGTH` slots. (A block `B` is justified if there is a descendant of `B` in `store` the processing of which sets `B` as justified.) If no such descendant exists set `justified_head` to `finalized_head`. * Let `justified_head` be the descendant of `finalized_head` with the highest slot number that has been justified for at least `EPOCH_LENGTH` slots. (A block `B` is justified if there is a descendant of `B` in `store` the processing of which sets `B` as justified.) If no such descendant exists set `justified_head` to `finalized_head`.
* Let `get_ancestor(store, block, slot)` be the ancestor of `block` with slot number `slot`. The `get_ancestor` function can be defined recursively as `def get_ancestor(store, block, slot): return block if block.slot == slot else get_ancestor(store, store.get_parent(block), slot)`. * Let `get_ancestor(store, block, slot)` be the ancestor of `block` with slot number `slot`. The `get_ancestor` function can be defined recursively as `def get_ancestor(store, block, slot): return block if block.header.slot == slot else get_ancestor(store, store.get_parent(block), slot)`.
* Let `get_latest_attestation(store, validator)` be the attestation with the highest slot number in `store` from `validator`. If several such attestations exist, use the one the [validator](#dfn-validator) `v` observed first. * Let `get_latest_attestation(store, validator)` be the attestation with the highest slot number in `store` from `validator`. If several such attestations exist, use the one the [validator](#dfn-validator) `v` observed first.
* Let `get_latest_attestation_target(store, validator)` be the target block in the attestation `get_latest_attestation(store, validator)`. * Let `get_latest_attestation_target(store, validator)` be the target block in the attestation `get_latest_attestation(store, validator)`.
* The head is `lmd_ghost(store, justified_head)` where the function `lmd_ghost` is defined below. Note that the implementation below is suboptimal; there are implementations that compute the head in time logarithmic in slot count. * The head is `lmd_ghost(store, justified_head)` where the function `lmd_ghost` is defined below. Note that the implementation below is suboptimal; there are implementations that compute the head in time logarithmic in slot count.
@ -667,7 +679,7 @@ def lmd_ghost(store, start):
for validator in active_validators] for validator in active_validators]
def get_vote_count(block): def get_vote_count(block):
return len([target for target in attestation_targets if return len([target for target in attestation_targets if
get_ancestor(store, target, block.slot) == block]) get_ancestor(store, target, block.header.slot) == block])
head = start head = start
while 1: while 1:
@ -874,9 +886,9 @@ def get_beacon_proposer_index(state: BeaconState,
```python ```python
def get_updated_ancestor_hashes(latest_block: BeaconBlock, def get_updated_ancestor_hashes(latest_block: BeaconBlock,
latest_hash: Hash32) -> List[Hash32]: latest_hash: Hash32) -> List[Hash32]:
new_ancestor_hashes = copy.deepcopy(latest_block.ancestor_hashes) new_ancestor_hashes = copy.deepcopy(latest_block.header.ancestor_hashes)
for i in range(32): for i in range(32):
if latest_block.slot % 2**i == 0: if latest_block.header.slot % 2**i == 0:
new_ancestor_hashes[i] = latest_hash new_ancestor_hashes[i] = latest_hash
return new_ancestor_hashes return new_ancestor_hashes
``` ```
@ -1212,8 +1224,8 @@ Below are the processing steps that happen at every slot.
If there is a block from the proposer for `state.slot`, we process that incoming block: If there is a block from the proposer for `state.slot`, we process that incoming block:
* Let `block` be that associated incoming block. * Let `block` be that associated incoming block.
* Verify that `block.slot == state.slot` * Verify that `block.header.slot == state.slot`
* Verify that `block.ancestor_hashes` equals `get_updated_ancestor_hashes(latest_block, latest_hash)`. * Verify that `block.header.ancestor_hashes` equals `get_updated_ancestor_hashes(latest_block, latest_hash)`.
If there is no block from the proposer at state.slot: If there is no block from the proposer at state.slot:
* Set `state.validator_registry[get_beacon_proposer_index(state, state.slot)].randao_skips += 1`. * Set `state.validator_registry[get_beacon_proposer_index(state, state.slot)].randao_skips += 1`.
@ -1221,15 +1233,15 @@ If there is no block from the proposer at state.slot:
### Proposer signature ### Proposer signature
* Let `block_hash_without_sig` be the hash of `block` where `proposer_signature` is set to `[0, 0]`. * Let `block_hash_without_sig` be the hash of `block` where `block.header.signature` is set to `[0, 0]`.
* Let `proposal_hash = hash(ProposalSignedData(state.slot, BEACON_CHAIN_SHARD_NUMBER, block_hash_without_sig))`. * Let `proposal_hash = hash(ProposalSignedData(state.slot, BEACON_CHAIN_SHARD_NUMBER, block_hash_without_sig))`.
* Verify that `BLSVerify(pubkey=state.validator_registry[get_beacon_proposer_index(state, state.slot)].pubkey, data=proposal_hash, sig=block.proposer_signature, domain=get_domain(state.fork_data, state.slot, DOMAIN_PROPOSAL))`. * Verify that `BLSVerify(pubkey=state.validator_registry[get_beacon_proposer_index(state, state.slot)].pubkey, data=proposal_hash, sig=block.header.signature, domain=get_domain(state.fork_data, state.slot, DOMAIN_PROPOSAL))`.
### Attestations ### Attestations
* Verify that `len(block.attestations) <= MAX_ATTESTATIONS_PER_BLOCK`. * Verify that `len(block.body.attestations) <= MAX_ATTESTATIONS_PER_BLOCK`.
For each `attestation` in `block.attestations`: For each `attestation` in `block.body.attestations`:
* Verify that `attestation.data.slot <= state.slot - MIN_ATTESTATION_INCLUSION_DELAY`. * Verify that `attestation.data.slot <= state.slot - MIN_ATTESTATION_INCLUSION_DELAY`.
* Verify that `attestation.data.slot >= max(state.slot - EPOCH_LENGTH, 0)`. * Verify that `attestation.data.slot >= max(state.slot - EPOCH_LENGTH, 0)`.
@ -1247,22 +1259,22 @@ For each `attestation` in `block.attestations`:
* Let `repeat_hash(x, n) = x if n == 0 else repeat_hash(hash(x), n-1)`. * Let `repeat_hash(x, n) = x if n == 0 else repeat_hash(hash(x), n-1)`.
* Let `proposer = state.validator_registry[get_beacon_proposer_index(state, state.slot)]`. * Let `proposer = state.validator_registry[get_beacon_proposer_index(state, state.slot)]`.
* Verify that `repeat_hash(block.randao_reveal, proposer.randao_skips + 1) == proposer.randao_commitment`. * Verify that `repeat_hash(block.header.randao_reveal, proposer.randao_skips + 1) == proposer.randao_commitment`.
* Set `state.randao_mix = xor(state.randao_mix, block.randao_reveal)`. * Set `state.randao_mix = xor(state.randao_mix, block.header.randao_reveal)`.
* Set `proposer.randao_commitment = block.randao_reveal`. * Set `proposer.randao_commitment = block.header.randao_reveal`.
* Set `proposer.randao_skips = 0`. * Set `proposer.randao_skips = 0`.
### PoW receipt root ### PoW receipt root
* If `block.candidate_pow_receipt_root` is `x.candidate_pow_receipt_root` for some `x` in `state.candidate_pow_receipt_roots`, set `x.votes += 1`. * If `block.header.candidate_pow_receipt_root` is `x.candidate_pow_receipt_root` for some `x` in `state.candidate_pow_receipt_roots`, set `x.votes += 1`.
* Otherwise, append to `state.candidate_pow_receipt_roots` a new `CandidatePoWReceiptRootRecord(candidate_pow_receipt_root=block.candidate_pow_receipt_root, votes=1)`. * Otherwise, append to `state.candidate_pow_receipt_roots` a new `CandidatePoWReceiptRootRecord(candidate_pow_receipt_root=block.header.candidate_pow_receipt_root, votes=1)`.
### Special objects ### Special objects
* Verify that the quantity of each type of object in `block.specials` is less than or equal to its maximum (see table at the top). * Verify that the quantity of each type of object in `block.body.specials` is less than or equal to its maximum (see table at the top).
* Verify that objects are sorted in order of `kind`. That is, `block.specials[i+1].kind >= block.specials[i].kind` for `0 <= i < len(block.specials-1)`. * Verify that objects are sorted in order of `kind`. That is, `block.body.specials[i+1].kind >= block.body.specials[i].kind` for `0 <= i < len(block.body.specials-1)`.
For each `special` in `block.specials`: For each `special` in `block.body.specials`:
* Verify that `special.kind` is a valid value. * Verify that `special.kind` is a valid value.
* Verify that `special.data` deserializes according to the format for the given `kind` (see format definitions in "Data structures" above). * Verify that `special.data` deserializes according to the format for the given `kind` (see format definitions in "Data structures" above).
@ -1592,7 +1604,7 @@ while len(state.persistent_committee_reassignments) > 0 and state.persistent_com
## State root processing ## State root processing
Verify `block.state_root == hash(state)` if there exists a `block` for the slot being processed. Verify `block.header.state_root == hash(state)` if there exists a `block` for the slot being processed.
# Appendix # Appendix
## Appendix A - Hash function ## Appendix A - Hash function