status-im/eth2.0-specs
2
0
Fork 0
mirror of https://github.com/status-im/eth2.0-specs.git synced 2025-02-20 22:38:11 +00:00
Code Issues Projects Releases Wiki Activity

Merge pull request #2393 from Nashatyrev/cosmetics/blob-subnet-name

Browse Source 
[Sharding] Network: Calculate {subnet_id} for shard_blob_ subnets
This commit is contained in:
Diederik Loerakker 2021-05-14 14:49:09 +02:00 committed by GitHub
commit 5984fd74b3
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 30 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
specs/sharding/p2p-interface.md
View File

@ -9,13 +9,15 @@
<!-- DON'T EDIT THIS SECTION, INSTEAD RE-RUN doctoc TO UPDATE -->
- [Introduction](#introduction)
- [Constants](#constants)
- [Misc](#misc)
- [New containers](#new-containers)
- [ShardBlobBody](#shardblobbody)
- [ShardBlob](#shardblob)
- [SignedShardBlob](#signedshardblob)
- [Gossip domain](#gossip-domain)
- [Topics and messages](#topics-and-messages)
- [Shard blobs: `shard_blob_{shard}`](#shard-blobs-shard_blob_shard)
- [Shard blobs: `shard_blob_{subnet_id}`](#shard-blobs-shard_blob_subnet_id)
- [Shard header: `shard_header`](#shard-header-shard_header)
- [Shard proposer slashing: `shard_proposer_slashing`](#shard-proposer-slashing-shard_proposer_slashing)
@ -29,6 +31,14 @@ The specification of these changes continues in the same format as the [Phase0](
[Altair](../altair/p2p-interface.md) network specifications, and assumes them as pre-requisite.
The adjustments and additions for Shards are outlined in this document.
## Constants
### Misc
| Name | Value | Description |
| ---- | ----- | ----------- |
| `SHARD_BLOB_SUBNET_COUNT` | `64` | The number of `shard_blob_{subnet_id}` subnets used in the gossipsub protocol. |
## New containers
### ShardBlobBody
@ -77,23 +87,38 @@ Following the same scheme as the [Phase0 gossip topics](../phase0/p2p-interface.
| Name | Message Type |
|----------------------------------|---------------------------|
| `shard_blob_{shard}` | `SignedShardBlob` |
| `shard_blob_{subnet_id}` | `SignedShardBlob` |
| `shard_header` | `SignedShardHeader` |
| `shard_proposer_slashing` | `ShardProposerSlashing` |
The [DAS network specification](./das-p2p.md) defines additional topics.
#### Shard blobs: `shard_blob_{shard}`
#### Shard blobs: `shard_blob_{subnet_id}`
Shard block data, in the form of a `SignedShardBlob` is published to the `shard_blob_{shard}` subnets.
Shard block data, in the form of a `SignedShardBlob` is published to the `shard_blob_{subnet_id}` subnets.
```python
def compute_subnet_for_shard_blob(state: BeaconState, slot: Slot, shard: Shard) -> uint64:
"""
Compute the correct subnet for a shard blob publication.
Note, this mimics compute_subnet_for_attestation().
"""
committee_index = compute_committee_index_from_shard(state, slot, shard)
committees_per_slot = get_committee_count_per_slot(state, compute_epoch_at_slot(slot))
slots_since_epoch_start = Slot(slot % SLOTS_PER_EPOCH)
committees_since_epoch_start = committees_per_slot * slots_since_epoch_start
return uint64((committees_since_epoch_start + committee_index) % SHARD_BLOB_SUBNET_COUNT)
```
The following validations MUST pass before forwarding the `signed_blob` (with inner `message` as `blob`) on the horizontal subnet or creating samples for it.
- _[REJECT]_ `blob.shard` MUST match the topic `{shard}` parameter. (And thus within valid shard index range)
- _[IGNORE]_ The `blob` is not from a future slot (with a `MAXIMUM_GOSSIP_CLOCK_DISPARITY` allowance) --
i.e. validate that `blob.slot <= current_slot`
(a client MAY queue future blobs for processing at the appropriate slot).
- _[IGNORE]_ The `blob` is new enough to be still be processed --
i.e. validate that `compute_epoch_at_slot(blob.slot) >= get_previous_epoch(state)`
- _[REJECT]_ The shard blob is for the correct subnet --
i.e. `compute_subnet_for_shard_blob(state, blob.slot, blob.shard) == subnet_id`
- _[IGNORE]_ The blob is the first blob with valid signature received for the `(blob.proposer_index, blob.slot, blob.shard)` combination.
- _[REJECT]_ As already limited by the SSZ list-limit, it is important the blob is well-formatted and not too large.
- _[REJECT]_ The `blob.body.data` MUST NOT contain any point `p >= MODULUS`. Although it is a `uint256`, not the full 256 bit range is valid.