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// Copyright (C) Parity Technologies (UK) Ltd.
// This file is part of Polkadot.
// Polkadot is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Polkadot is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Polkadot. If not, see <http://www.gnu.org/licenses/>.
//! Message types for the overseer and subsystems.
//!
//! These messages are intended to define the protocol by which different subsystems communicate
//! with each other and signals that they receive from an overseer to coordinate their work.
//! This is intended for use with the `polkadot-overseer` crate.
//!
//! Subsystems' APIs are defined separately from their implementation, leading to easier mocking.
use futures::channel::oneshot;
use sc_network::{Multiaddr, ReputationChange};
use thiserror::Error;
pub use sc_network::IfDisconnected;
use polkadot_node_network_protocol::{
self as net_protocol, peer_set::PeerSet, request_response::Requests, PeerId,
};
use polkadot_node_primitives::{
approval::{BlockApprovalMeta, IndirectAssignmentCert, IndirectSignedApprovalVote},
AvailableData, BabeEpoch, BlockWeight, CandidateVotes, CollationGenerationConfig,
CollationSecondedSignal, DisputeMessage, DisputeStatus, ErasureChunk, PoV,
SignedDisputeStatement, SignedFullStatement, SignedFullStatementWithPVD, SubmitCollationParams,
ValidationResult,
};
use polkadot_primitives::{
slashing, vstaging as vstaging_primitives, AuthorityDiscoveryId, BackedCandidate, BlockNumber,
CandidateEvent, CandidateHash, CandidateIndex, CandidateReceipt, CollatorId,
CommittedCandidateReceipt, CoreState, DisputeState, ExecutorParams, GroupIndex,
GroupRotationInfo, Hash, Header as BlockHeader, Id as ParaId, InboundDownwardMessage,
InboundHrmpMessage, MultiDisputeStatementSet, OccupiedCoreAssumption, PersistedValidationData,
PvfCheckStatement, PvfExecTimeoutKind, SessionIndex, SessionInfo, SignedAvailabilityBitfield,
SignedAvailabilityBitfields, ValidationCode, ValidationCodeHash, ValidatorId, ValidatorIndex,
ValidatorSignature,
};
use polkadot_statement_table::v2::Misbehavior;
use std::{
collections::{BTreeMap, HashMap, HashSet},
sync::Arc,
};
/// Network events as transmitted to other subsystems, wrapped in their message types.
pub mod network_bridge_event;
pub use network_bridge_event::NetworkBridgeEvent;
/// A request to the candidate backing subsystem to check whether
/// there exists vacant membership in some fragment tree.
#[derive(Debug, Copy, Clone)]
pub struct CanSecondRequest {
/// Para id of the candidate.
pub candidate_para_id: ParaId,
/// The relay-parent of the candidate.
pub candidate_relay_parent: Hash,
/// Hash of the candidate.
pub candidate_hash: CandidateHash,
/// Parent head data hash.
pub parent_head_data_hash: Hash,
}
/// Messages received by the Candidate Backing subsystem.
#[derive(Debug)]
pub enum CandidateBackingMessage {
/// Requests a set of backable candidates attested by the subsystem.
///
/// Each pair is (candidate_hash, candidate_relay_parent).
GetBackedCandidates(Vec<(CandidateHash, Hash)>, oneshot::Sender<Vec<BackedCandidate>>),
/// Request the subsystem to check whether it's allowed to second given candidate.
/// The rule is to only fetch collations that are either built on top of the root
/// of some fragment tree or have a parent node which represents backed candidate.
///
/// Always responses with `false` if async backing is disabled for candidate's relay
/// parent.
CanSecond(CanSecondRequest, oneshot::Sender<bool>),
/// Note that the Candidate Backing subsystem should second the given candidate in the context
/// of the given relay-parent (ref. by hash). This candidate must be validated.
Second(Hash, CandidateReceipt, PersistedValidationData, PoV),
/// Note a validator's statement about a particular candidate in the context of the given
/// relay-parent. Disagreements about validity must be escalated to a broader check by the
/// Disputes Subsystem, though that escalation is deferred until the approval voting stage to
/// guarantee availability. Agreements are simply tallied until a quorum is reached.
Statement(Hash, SignedFullStatementWithPVD),
}
/// Blanket error for validation failing for internal reasons.
#[derive(Debug, Error)]
#[error("Validation failed with {0:?}")]
pub struct ValidationFailed(pub String);
/// The outcome of the candidate-validation's PVF pre-check request.
#[derive(Debug, PartialEq)]
pub enum PreCheckOutcome {
/// The PVF has been compiled successfully within the given constraints.
Valid,
/// The PVF could not be compiled. This variant is used when the candidate-validation subsystem
/// can be sure that the PVF is invalid. To give a couple of examples: a PVF that cannot be
/// decompressed or that does not represent a structurally valid WebAssembly file.
Invalid,
/// This variant is used when the PVF cannot be compiled but for other reasons that are not
/// included into [`PreCheckOutcome::Invalid`]. This variant can indicate that the PVF in
/// question is invalid, however it is not necessary that PVF that received this judgement
/// is invalid.
///
/// For example, if during compilation the preparation worker was killed we cannot be sure why
/// it happened: because the PVF was malicious made the worker to use too much memory or its
/// because the host machine is under severe memory pressure and it decided to kill the worker.
Failed,
}
/// Messages received by the Validation subsystem.
///
/// ## Validation Requests
///
/// Validation requests made to the subsystem should return an error only on internal error.
/// Otherwise, they should return either `Ok(ValidationResult::Valid(_))`
/// or `Ok(ValidationResult::Invalid)`.
#[derive(Debug)]
pub enum CandidateValidationMessage {
/// Validate a candidate with provided parameters using relay-chain state.
///
/// This will implicitly attempt to gather the `PersistedValidationData` and `ValidationCode`
/// from the runtime API of the chain, based on the `relay_parent`
/// of the `CandidateReceipt`.
///
/// This will also perform checking of validation outputs against the acceptance criteria.
///
/// If there is no state available which can provide this data or the core for
/// the para is not free at the relay-parent, an error is returned.
ValidateFromChainState(
CandidateReceipt,
Arc<PoV>,
ExecutorParams,
/// Execution timeout
PvfExecTimeoutKind,
oneshot::Sender<Result<ValidationResult, ValidationFailed>>,
),
/// Validate a candidate with provided, exhaustive parameters for validation.
///
/// Explicitly provide the `PersistedValidationData` and `ValidationCode` so this can do full
/// validation without needing to access the state of the relay-chain.
///
/// This request doesn't involve acceptance criteria checking, therefore only useful for the
/// cases where the validity of the candidate is established. This is the case for the typical
/// use-case: secondary checkers would use this request relying on the full prior checks
/// performed by the relay-chain.
ValidateFromExhaustive(
PersistedValidationData,
ValidationCode,
CandidateReceipt,
Arc<PoV>,
ExecutorParams,
/// Execution timeout
PvfExecTimeoutKind,
oneshot::Sender<Result<ValidationResult, ValidationFailed>>,
),
/// Try to compile the given validation code and send back
/// the outcome.
///
/// The validation code is specified by the hash and will be queried from the runtime API at
/// the given relay-parent.
PreCheck(
// Relay-parent
Hash,
ValidationCodeHash,
oneshot::Sender<PreCheckOutcome>,
),
}
/// Messages received by the Collator Protocol subsystem.
#[derive(Debug, derive_more::From)]
pub enum CollatorProtocolMessage {
/// Signal to the collator protocol that it should connect to validators with the expectation
/// of collating on the given para. This is only expected to be called once, early on, if at
/// all, and only by the Collation Generation subsystem. As such, it will overwrite the value
/// of the previous signal.
///
/// This should be sent before any `DistributeCollation` message.
CollateOn(ParaId),
/// Provide a collation to distribute to validators with an optional result sender.
/// The second argument is the parent head-data hash.
///
/// The result sender should be informed when at least one parachain validator seconded the
/// collation. It is also completely okay to just drop the sender.
DistributeCollation(
CandidateReceipt,
Hash,
PoV,
Option<oneshot::Sender<CollationSecondedSignal>>,
),
/// Report a collator as having provided an invalid collation. This should lead to disconnect
/// and blacklist of the collator.
ReportCollator(CollatorId),
/// Get a network bridge update.
#[from]
NetworkBridgeUpdate(NetworkBridgeEvent<net_protocol::CollatorProtocolMessage>),
/// We recommended a particular candidate to be seconded, but it was invalid; penalize the
/// collator.
///
/// The hash is the relay parent.
Invalid(Hash, CandidateReceipt),
/// The candidate we recommended to be seconded was validated successfully.
///
/// The hash is the relay parent.
Seconded(Hash, SignedFullStatement),
/// The candidate received enough validity votes from the backing group.
Backed {
/// Candidate's para id.
para_id: ParaId,
/// Hash of the para head generated by candidate.
para_head: Hash,
},
}
impl Default for CollatorProtocolMessage {
fn default() -> Self {
Self::CollateOn(Default::default())
}
}
/// Messages received by the dispute coordinator subsystem.
///
/// NOTE: Any response oneshots might get cancelled if the `DisputeCoordinator` was not yet
/// properly initialized for some reason.
#[derive(Debug)]
pub enum DisputeCoordinatorMessage {
/// Import statements by validators about a candidate.
///
/// The subsystem will silently discard ancient statements or sets of only dispute-specific
/// statements for candidates that are previously unknown to the subsystem. The former is
/// simply because ancient data is not relevant and the latter is as a DoS prevention
/// mechanism. Both backing and approval statements already undergo anti-DoS procedures in
/// their respective subsystems, but statements cast specifically for disputes are not
/// necessarily relevant to any candidate the system is already aware of and thus present a DoS
/// vector. Our expectation is that nodes will notify each other of disputes over the network
/// by providing (at least) 2 conflicting statements, of which one is either a backing or
/// validation statement.
///
/// This does not do any checking of the message signature.
ImportStatements {
/// The candidate receipt itself.
candidate_receipt: CandidateReceipt,
/// The session the candidate appears in.
session: SessionIndex,
/// Statements, with signatures checked, by validators participating in disputes.
///
/// The validator index passed alongside each statement should correspond to the index
/// of the validator in the set.
statements: Vec<(SignedDisputeStatement, ValidatorIndex)>,
/// Inform the requester once we finished importing (if a sender was provided).
///
/// This is:
/// - we discarded the votes because
/// - they were ancient or otherwise invalid (result: `InvalidImport`)
/// - or we were not able to recover availability for an unknown candidate (result:
/// `InvalidImport`)
/// - or were known already (in that case the result will still be `ValidImport`)
/// - or we recorded them because (`ValidImport`)
/// - we cast our own vote already on that dispute
/// - or we have approval votes on that candidate
/// - or other explicit votes on that candidate already recorded
/// - or recovered availability for the candidate
/// - or the imported statements are backing/approval votes, which are always accepted.
pending_confirmation: Option<oneshot::Sender<ImportStatementsResult>>,
},
/// Fetch a list of all recent disputes the coordinator is aware of.
/// These are disputes which have occurred any time in recent sessions,
/// and which may have already concluded.
RecentDisputes(oneshot::Sender<Vec<(SessionIndex, CandidateHash, DisputeStatus)>>),
/// Fetch a list of all active disputes that the coordinator is aware of.
/// These disputes are either not yet concluded or recently concluded.
ActiveDisputes(oneshot::Sender<Vec<(SessionIndex, CandidateHash, DisputeStatus)>>),
/// Get candidate votes for a candidate.
QueryCandidateVotes(
Vec<(SessionIndex, CandidateHash)>,
oneshot::Sender<Vec<(SessionIndex, CandidateHash, CandidateVotes)>>,
),
/// Sign and issue local dispute votes. A value of `true` indicates validity, and `false`
/// invalidity.
IssueLocalStatement(SessionIndex, CandidateHash, CandidateReceipt, bool),
/// Determine the highest undisputed block within the given chain, based on where candidates
/// were included. If even the base block should not be finalized due to a dispute,
/// then `None` should be returned on the channel.
///
/// The block descriptions begin counting upwards from the block after the given `base_number`.
/// The `base_number` is typically the number of the last finalized block but may be slightly
/// higher. This block is inevitably going to be finalized so it is not accounted for by this
/// function.
DetermineUndisputedChain {
/// The lowest possible block to vote on.
base: (BlockNumber, Hash),
/// Descriptions of all the blocks counting upwards from the block after the base number
block_descriptions: Vec<BlockDescription>,
/// The block to vote on, might be base in case there is no better.
tx: oneshot::Sender<(BlockNumber, Hash)>,
},
}
/// The result of `DisputeCoordinatorMessage::ImportStatements`.
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub enum ImportStatementsResult {
/// Import was invalid (candidate was not available) and the sending peer should get banned.
InvalidImport,
/// Import was valid and can be confirmed to peer.
ValidImport,
}
/// Messages going to the dispute distribution subsystem.
#[derive(Debug)]
pub enum DisputeDistributionMessage {
/// Tell dispute distribution to distribute an explicit dispute statement to
/// validators.
SendDispute(DisputeMessage),
}
/// Messages received from other subsystems.
#[derive(Debug)]
pub enum NetworkBridgeRxMessage {
/// Inform the distribution subsystems about the new
/// gossip network topology formed.
///
/// The only reason to have this here, is the availability of the
/// authority discovery service, otherwise, the `GossipSupport`
/// subsystem would make more sense.
NewGossipTopology {
/// The session info this gossip topology is concerned with.
session: SessionIndex,
/// Our validator index in the session, if any.
local_index: Option<ValidatorIndex>,
/// The canonical shuffling of validators for the session.
canonical_shuffling: Vec<(AuthorityDiscoveryId, ValidatorIndex)>,
/// The reverse mapping of `canonical_shuffling`: from validator index
/// to the index in `canonical_shuffling`
shuffled_indices: Vec<usize>,
},
/// Inform the distribution subsystems about `AuthorityDiscoveryId` key rotations.
UpdatedAuthorityIds {
/// The `PeerId` of the peer that updated its `AuthorityDiscoveryId`s.
peer_id: PeerId,
/// The updated authority discovery keys of the peer.
authority_ids: HashSet<AuthorityDiscoveryId>,
},
}
/// Type of peer reporting
#[derive(Debug)]
pub enum ReportPeerMessage {
/// Single peer report about malicious actions which should be sent right away
Single(PeerId, ReputationChange),
/// Delayed report for other actions.
Batch(HashMap<PeerId, i32>),
}
/// Messages received from other subsystems by the network bridge subsystem.
#[derive(Debug)]
pub enum NetworkBridgeTxMessage {
/// Report a peer for their actions.
ReportPeer(ReportPeerMessage),
/// Disconnect a peer from the given peer-set without affecting their reputation.
DisconnectPeer(PeerId, PeerSet),
/// Send a message to one or more peers on the validation peer-set.
SendValidationMessage(Vec<PeerId>, net_protocol::VersionedValidationProtocol),
/// Send a message to one or more peers on the collation peer-set.
SendCollationMessage(Vec<PeerId>, net_protocol::VersionedCollationProtocol),
/// Send a batch of validation messages.
///
/// NOTE: Messages will be processed in order (at least statement distribution relies on this).
SendValidationMessages(Vec<(Vec<PeerId>, net_protocol::VersionedValidationProtocol)>),
/// Send a batch of collation messages.
///
/// NOTE: Messages will be processed in order.
SendCollationMessages(Vec<(Vec<PeerId>, net_protocol::VersionedCollationProtocol)>),
/// Send requests via substrate request/response.
/// Second parameter, tells what to do if we are not yet connected to the peer.
SendRequests(Vec<Requests>, IfDisconnected),
/// Connect to peers who represent the given `validator_ids`.
///
/// Also ask the network to stay connected to these peers at least
/// until a new request is issued.
///
/// Because it overrides the previous request, it must be ensured
/// that `validator_ids` include all peers the subsystems
/// are interested in (per `PeerSet`).
///
/// A caller can learn about validator connections by listening to the
/// `PeerConnected` events from the network bridge.
ConnectToValidators {
/// Ids of the validators to connect to.
validator_ids: Vec<AuthorityDiscoveryId>,
/// The underlying protocol to use for this request.
peer_set: PeerSet,
/// Sends back the number of `AuthorityDiscoveryId`s which
/// authority discovery has failed to resolve.
failed: oneshot::Sender<usize>,
},
/// Alternative to `ConnectToValidators` in case you already know the `Multiaddrs` you want to
/// be connected to.
ConnectToResolvedValidators {
/// Each entry corresponds to the addresses of an already resolved validator.
validator_addrs: Vec<HashSet<Multiaddr>>,
/// The peer set we want the connection on.
peer_set: PeerSet,
},
}
/// Availability Distribution Message.
#[derive(Debug)]
pub enum AvailabilityDistributionMessage {
/// Instruct availability distribution to fetch a remote PoV.
///
/// NOTE: The result of this fetch is not yet locally validated and could be bogus.
FetchPoV {
/// The relay parent giving the necessary context.
relay_parent: Hash,
/// Validator to fetch the PoV from.
from_validator: ValidatorIndex,
/// The id of the parachain that produced this PoV.
/// This field is only used to provide more context when logging errors
/// from the `AvailabilityDistribution` subsystem.
para_id: ParaId,
/// Candidate hash to fetch the PoV for.
candidate_hash: CandidateHash,
/// Expected hash of the PoV, a PoV not matching this hash will be rejected.
pov_hash: Hash,
/// Sender for getting back the result of this fetch.
///
/// The sender will be canceled if the fetching failed for some reason.
tx: oneshot::Sender<PoV>,
},
}
/// Availability Recovery Message.
#[derive(Debug, derive_more::From)]
pub enum AvailabilityRecoveryMessage {
/// Recover available data from validators on the network.
RecoverAvailableData(
CandidateReceipt,
SessionIndex,
Option<GroupIndex>, // Optional backing group to request from first.
oneshot::Sender<Result<AvailableData, crate::errors::RecoveryError>>,
),
}
/// Bitfield distribution message.
#[derive(Debug, derive_more::From)]
pub enum BitfieldDistributionMessage {
/// Distribute a bitfield via gossip to other validators.
DistributeBitfield(Hash, SignedAvailabilityBitfield),
/// Event from the network bridge.
#[from]
NetworkBridgeUpdate(NetworkBridgeEvent<net_protocol::BitfieldDistributionMessage>),
}
/// Availability store subsystem message.
#[derive(Debug)]
pub enum AvailabilityStoreMessage {
/// Query a `AvailableData` from the AV store.
QueryAvailableData(CandidateHash, oneshot::Sender<Option<AvailableData>>),
/// Query whether a `AvailableData` exists within the AV Store.
///
/// This is useful in cases when existence
/// matters, but we don't want to necessarily pass around multiple
/// megabytes of data to get a single bit of information.
QueryDataAvailability(CandidateHash, oneshot::Sender<bool>),
/// Query an `ErasureChunk` from the AV store by the candidate hash and validator index.
QueryChunk(CandidateHash, ValidatorIndex, oneshot::Sender<Option<ErasureChunk>>),
/// Get the size of an `ErasureChunk` from the AV store by the candidate hash.
QueryChunkSize(CandidateHash, oneshot::Sender<Option<usize>>),
/// Query all chunks that we have for the given candidate hash.
QueryAllChunks(CandidateHash, oneshot::Sender<Vec<ErasureChunk>>),
/// Query whether an `ErasureChunk` exists within the AV Store.
///
/// This is useful in cases like bitfield signing, when existence
/// matters, but we don't want to necessarily pass around large
/// quantities of data to get a single bit of information.
QueryChunkAvailability(CandidateHash, ValidatorIndex, oneshot::Sender<bool>),
/// Store an `ErasureChunk` in the AV store.
///
/// Return `Ok(())` if the store operation succeeded, `Err(())` if it failed.
StoreChunk {
/// A hash of the candidate this chunk belongs to.
candidate_hash: CandidateHash,
/// The chunk itself.
chunk: ErasureChunk,
/// Sending side of the channel to send result to.
tx: oneshot::Sender<Result<(), ()>>,
},
/// Computes and checks the erasure root of `AvailableData` before storing all of its chunks in
/// the AV store.
///
/// Return `Ok(())` if the store operation succeeded, `Err(StoreAvailableData)` if it failed.
StoreAvailableData {
/// A hash of the candidate this `available_data` belongs to.
candidate_hash: CandidateHash,
/// The number of validators in the session.
n_validators: u32,
/// The `AvailableData` itself.
available_data: AvailableData,
/// Erasure root we expect to get after chunking.
expected_erasure_root: Hash,
/// Sending side of the channel to send result to.
tx: oneshot::Sender<Result<(), StoreAvailableDataError>>,
},
}
/// The error result type of a [`AvailabilityStoreMessage::StoreAvailableData`] request.
#[derive(Error, Debug, Clone, PartialEq, Eq)]
#[allow(missing_docs)]
pub enum StoreAvailableDataError {
#[error("The computed erasure root did not match expected one")]
InvalidErasureRoot,
}
/// A response channel for the result of a chain API request.
pub type ChainApiResponseChannel<T> = oneshot::Sender<Result<T, crate::errors::ChainApiError>>;
/// Chain API request subsystem message.
#[derive(Debug)]
pub enum ChainApiMessage {
/// Request the block number by hash.
/// Returns `None` if a block with the given hash is not present in the db.
BlockNumber(Hash, ChainApiResponseChannel<Option<BlockNumber>>),
/// Request the block header by hash.
/// Returns `None` if a block with the given hash is not present in the db.
BlockHeader(Hash, ChainApiResponseChannel<Option<BlockHeader>>),
/// Get the cumulative weight of the given block, by hash.
/// If the block or weight is unknown, this returns `None`.
///
/// Note: this is the weight within the low-level fork-choice rule,
/// not the high-level one implemented in the chain-selection subsystem.
///
/// Weight is used for comparing blocks in a fork-choice rule.
BlockWeight(Hash, ChainApiResponseChannel<Option<BlockWeight>>),
/// Request the finalized block hash by number.
/// Returns `None` if a block with the given number is not present in the db.
/// Note: the caller must ensure the block is finalized.
FinalizedBlockHash(BlockNumber, ChainApiResponseChannel<Option<Hash>>),
/// Request the last finalized block number.
/// This request always succeeds.
FinalizedBlockNumber(ChainApiResponseChannel<BlockNumber>),
/// Request the `k` ancestor block hashes of a block with the given hash.
/// The response channel may return a `Vec` of size up to `k`
/// filled with ancestors hashes with the following order:
/// `parent`, `grandparent`, ... up to the hash of genesis block
/// with number 0, including it.
Ancestors {
/// The hash of the block in question.
hash: Hash,
/// The number of ancestors to request.
k: usize,
/// The response channel.
response_channel: ChainApiResponseChannel<Vec<Hash>>,
},
}
/// Chain selection subsystem messages
#[derive(Debug)]
pub enum ChainSelectionMessage {
/// Signal to the chain selection subsystem that a specific block has been approved.
Approved(Hash),
/// Request the leaves in descending order by score.
Leaves(oneshot::Sender<Vec<Hash>>),
/// Request the best leaf containing the given block in its ancestry. Return `None` if
/// there is no such leaf.
BestLeafContaining(Hash, oneshot::Sender<Option<Hash>>),
/// The passed blocks must be marked as reverted, and their children must be marked
/// as non-viable.
RevertBlocks(Vec<(BlockNumber, Hash)>),
}
/// A sender for the result of a runtime API request.
pub type RuntimeApiSender<T> = oneshot::Sender<Result<T, crate::errors::RuntimeApiError>>;
/// A request to the Runtime API subsystem.
#[derive(Debug)]
pub enum RuntimeApiRequest {
/// Get the version of the runtime API, if any.
Version(RuntimeApiSender<u32>),
/// Get the next, current and some previous authority discovery set deduplicated.
Authorities(RuntimeApiSender<Vec<AuthorityDiscoveryId>>),
/// Get the current validator set.
Validators(RuntimeApiSender<Vec<ValidatorId>>),
/// Get the validator groups and group rotation info.
ValidatorGroups(RuntimeApiSender<(Vec<Vec<ValidatorIndex>>, GroupRotationInfo)>),
/// Get information on all availability cores.
AvailabilityCores(RuntimeApiSender<Vec<CoreState>>),
/// Get the persisted validation data for a particular para, taking the given
/// `OccupiedCoreAssumption`, which will inform on how the validation data should be computed
/// if the para currently occupies a core.
PersistedValidationData(
ParaId,
OccupiedCoreAssumption,
RuntimeApiSender<Option<PersistedValidationData>>,
),
/// Get the persisted validation data for a particular para along with the current validation
/// code hash, matching the data hash against an expected one.
AssumedValidationData(
ParaId,
Hash,
RuntimeApiSender<Option<(PersistedValidationData, ValidationCodeHash)>>,
),
/// Sends back `true` if the validation outputs pass all acceptance criteria checks.
CheckValidationOutputs(
ParaId,
polkadot_primitives::CandidateCommitments,
RuntimeApiSender<bool>,
),
/// Get the session index that a child of the block will have.
SessionIndexForChild(RuntimeApiSender<SessionIndex>),
/// Get the validation code for a para, taking the given `OccupiedCoreAssumption`, which
/// will inform on how the validation data should be computed if the para currently
/// occupies a core.
ValidationCode(ParaId, OccupiedCoreAssumption, RuntimeApiSender<Option<ValidationCode>>),
/// Get validation code by its hash, either past, current or future code can be returned, as
/// long as state is still available.
ValidationCodeByHash(ValidationCodeHash, RuntimeApiSender<Option<ValidationCode>>),
/// Get a the candidate pending availability for a particular parachain by parachain / core
/// index
CandidatePendingAvailability(ParaId, RuntimeApiSender<Option<CommittedCandidateReceipt>>),
/// Get all events concerning candidates (backing, inclusion, time-out) in the parent of
/// the block in whose state this request is executed.
CandidateEvents(RuntimeApiSender<Vec<CandidateEvent>>),
/// Get the execution environment parameter set by session index
SessionExecutorParams(SessionIndex, RuntimeApiSender<Option<ExecutorParams>>),
/// Get the session info for the given session, if stored.
SessionInfo(SessionIndex, RuntimeApiSender<Option<SessionInfo>>),
/// Get all the pending inbound messages in the downward message queue for a para.
DmqContents(ParaId, RuntimeApiSender<Vec<InboundDownwardMessage<BlockNumber>>>),
/// Get the contents of all channels addressed to the given recipient. Channels that have no
/// messages in them are also included.
InboundHrmpChannelsContents(
ParaId,
RuntimeApiSender<BTreeMap<ParaId, Vec<InboundHrmpMessage<BlockNumber>>>>,
),
/// Get information about the BABE epoch the block was included in.
CurrentBabeEpoch(RuntimeApiSender<BabeEpoch>),
/// Get all disputes in relation to a relay parent.
FetchOnChainVotes(RuntimeApiSender<Option<polkadot_primitives::ScrapedOnChainVotes>>),
/// Submits a PVF pre-checking statement into the transaction pool.
SubmitPvfCheckStatement(PvfCheckStatement, ValidatorSignature, RuntimeApiSender<()>),
/// Returns code hashes of PVFs that require pre-checking by validators in the active set.
PvfsRequirePrecheck(RuntimeApiSender<Vec<ValidationCodeHash>>),
/// Get the validation code used by the specified para, taking the given
/// `OccupiedCoreAssumption`, which will inform on how the validation data should be computed
/// if the para currently occupies a core.
ValidationCodeHash(
ParaId,
OccupiedCoreAssumption,
RuntimeApiSender<Option<ValidationCodeHash>>,
),
/// Returns all on-chain disputes at given block number. Available in `v3`.
Disputes(RuntimeApiSender<Vec<(SessionIndex, CandidateHash, DisputeState<BlockNumber>)>>),
/// Returns a list of validators that lost a past session dispute and need to be slashed.
/// `V5`
UnappliedSlashes(
RuntimeApiSender<Vec<(SessionIndex, CandidateHash, slashing::PendingSlashes)>>,
),
/// Returns a merkle proof of a validator session key.
/// `V5`
KeyOwnershipProof(ValidatorId, RuntimeApiSender<Option<slashing::OpaqueKeyOwnershipProof>>),
/// Submits an unsigned extrinsic to slash validator who lost a past session dispute.
/// `V5`
SubmitReportDisputeLost(
slashing::DisputeProof,
slashing::OpaqueKeyOwnershipProof,
RuntimeApiSender<Option<()>>,
),
/// Get the minimum required backing votes.
MinimumBackingVotes(SessionIndex, RuntimeApiSender<u32>),
/// Get the backing state of the given para.
/// This is a staging API that will not be available on production runtimes.
StagingParaBackingState(ParaId, RuntimeApiSender<Option<vstaging_primitives::BackingState>>),
/// Get candidate's acceptance limitations for asynchronous backing for a relay parent.
///
/// If it's not supported by the Runtime, the async backing is said to be disabled.
StagingAsyncBackingParams(RuntimeApiSender<vstaging_primitives::AsyncBackingParams>),
}
impl RuntimeApiRequest {
/// Runtime version requirements for each message
/// `Disputes`
pub const DISPUTES_RUNTIME_REQUIREMENT: u32 = 3;
/// `ExecutorParams`
pub const EXECUTOR_PARAMS_RUNTIME_REQUIREMENT: u32 = 4;
/// `UnappliedSlashes`
pub const UNAPPLIED_SLASHES_RUNTIME_REQUIREMENT: u32 = 5;
/// `KeyOwnershipProof`
pub const KEY_OWNERSHIP_PROOF_RUNTIME_REQUIREMENT: u32 = 5;
/// `SubmitReportDisputeLost`
pub const SUBMIT_REPORT_DISPUTE_LOST_RUNTIME_REQUIREMENT: u32 = 5;
/// `MinimumBackingVotes`
pub const MINIMUM_BACKING_VOTES_RUNTIME_REQUIREMENT: u32 = 6;
/// Minimum version for backing state, required for async backing.
///
/// 99 for now, should be adjusted to VSTAGING/actual runtime version once released.
pub const STAGING_BACKING_STATE: u32 = 99;
}
/// A message to the Runtime API subsystem.
#[derive(Debug)]
pub enum RuntimeApiMessage {
/// Make a request of the runtime API against the post-state of the given relay-parent.
Request(Hash, RuntimeApiRequest),
}
/// Statement distribution message.
#[derive(Debug, derive_more::From)]
pub enum StatementDistributionMessage {
/// We have originated a signed statement in the context of
/// given relay-parent hash and it should be distributed to other validators.
Share(Hash, SignedFullStatementWithPVD),
/// The candidate received enough validity votes from the backing group.
///
/// If the candidate is backed as a result of a local statement, this message MUST
/// be preceded by a `Share` message for that statement. This ensures that Statement
/// Distribution is always aware of full candidates prior to receiving the `Backed`
/// notification, even when the group size is 1 and the candidate is seconded locally.
Backed(CandidateHash),
/// Event from the network bridge.
#[from]
NetworkBridgeUpdate(NetworkBridgeEvent<net_protocol::StatementDistributionMessage>),
}
/// This data becomes intrinsics or extrinsics which should be included in a future relay chain
/// block.
// It needs to be cloneable because multiple potential block authors can request copies.
#[derive(Debug, Clone)]
pub enum ProvisionableData {
/// This bitfield indicates the availability of various candidate blocks.
Bitfield(Hash, SignedAvailabilityBitfield),
/// The Candidate Backing subsystem believes that this candidate is valid, pending
/// availability.
BackedCandidate(CandidateReceipt),
/// Misbehavior reports are self-contained proofs of validator misbehavior.
MisbehaviorReport(Hash, ValidatorIndex, Misbehavior),
/// Disputes trigger a broad dispute resolution process.
Dispute(Hash, ValidatorSignature),
}
/// Inherent data returned by the provisioner
#[derive(Debug, Clone)]
pub struct ProvisionerInherentData {
/// Signed bitfields.
pub bitfields: SignedAvailabilityBitfields,
/// Backed candidates.
pub backed_candidates: Vec<BackedCandidate>,
/// Dispute statement sets.
pub disputes: MultiDisputeStatementSet,
}
/// Message to the Provisioner.
///
/// In all cases, the Hash is that of the relay parent.
#[derive(Debug)]
pub enum ProvisionerMessage {
/// This message allows external subsystems to request the set of bitfields and backed
/// candidates associated with a particular potential block hash.
///
/// This is expected to be used by a proposer, to inject that information into the
/// `InherentData` where it can be assembled into the `ParaInherent`.
RequestInherentData(Hash, oneshot::Sender<ProvisionerInherentData>),
/// This data should become part of a relay chain block
ProvisionableData(Hash, ProvisionableData),
}
/// Message to the Collation Generation subsystem.
#[derive(Debug)]
pub enum CollationGenerationMessage {
/// Initialize the collation generation subsystem
Initialize(CollationGenerationConfig),
/// Submit a collation to the subsystem. This will package it into a signed
/// [`CommittedCandidateReceipt`] and distribute along the network to validators.
///
/// If sent before `Initialize`, this will be ignored.
SubmitCollation(SubmitCollationParams),
}
/// The result type of [`ApprovalVotingMessage::CheckAndImportAssignment`] request.
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum AssignmentCheckResult {
/// The vote was accepted and should be propagated onwards.
Accepted,
/// The vote was valid but duplicate and should not be propagated onwards.
AcceptedDuplicate,
/// The vote was valid but too far in the future to accept right now.
TooFarInFuture,
/// The vote was bad and should be ignored, reporting the peer who propagated it.
Bad(AssignmentCheckError),
}
/// The error result type of [`ApprovalVotingMessage::CheckAndImportAssignment`] request.
#[derive(Error, Debug, Clone, PartialEq, Eq)]
#[allow(missing_docs)]
pub enum AssignmentCheckError {
#[error("Unknown block: {0:?}")]
UnknownBlock(Hash),
#[error("Unknown session index: {0}")]
UnknownSessionIndex(SessionIndex),
#[error("Invalid candidate index: {0}")]
InvalidCandidateIndex(CandidateIndex),
#[error("Invalid candidate {0}: {1:?}")]
InvalidCandidate(CandidateIndex, CandidateHash),
#[error("Invalid cert: {0:?}, reason: {1}")]
InvalidCert(ValidatorIndex, String),
#[error("Internal state mismatch: {0:?}, {1:?}")]
Internal(Hash, CandidateHash),
}
/// The result type of [`ApprovalVotingMessage::CheckAndImportApproval`] request.
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum ApprovalCheckResult {
/// The vote was accepted and should be propagated onwards.
Accepted,
/// The vote was bad and should be ignored, reporting the peer who propagated it.
Bad(ApprovalCheckError),
}
/// The error result type of [`ApprovalVotingMessage::CheckAndImportApproval`] request.
#[derive(Error, Debug, Clone, PartialEq, Eq)]
#[allow(missing_docs)]
pub enum ApprovalCheckError {
#[error("Unknown block: {0:?}")]
UnknownBlock(Hash),
#[error("Unknown session index: {0}")]
UnknownSessionIndex(SessionIndex),
#[error("Invalid candidate index: {0}")]
InvalidCandidateIndex(CandidateIndex),
#[error("Invalid validator index: {0:?}")]
InvalidValidatorIndex(ValidatorIndex),
#[error("Invalid candidate {0}: {1:?}")]
InvalidCandidate(CandidateIndex, CandidateHash),
#[error("Invalid signature: {0:?}")]
InvalidSignature(ValidatorIndex),
#[error("No assignment for {0:?}")]
NoAssignment(ValidatorIndex),
#[error("Internal state mismatch: {0:?}, {1:?}")]
Internal(Hash, CandidateHash),
}
/// Describes a relay-chain block by the para-chain candidates
/// it includes.
#[derive(Clone, Debug)]
pub struct BlockDescription {
/// The relay-chain block hash.
pub block_hash: Hash,
/// The session index of this block.
pub session: SessionIndex,
/// The set of para-chain candidates.
pub candidates: Vec<CandidateHash>,
}
/// Response type to `ApprovalVotingMessage::ApprovedAncestor`.
#[derive(Clone, Debug)]
pub struct HighestApprovedAncestorBlock {
/// The block hash of the highest viable ancestor.
pub hash: Hash,
/// The block number of the highest viable ancestor.
pub number: BlockNumber,
/// Block descriptions in the direct path between the
/// initially provided hash and the highest viable ancestor.
/// Primarily for use with `DetermineUndisputedChain`.
/// Must be sorted from lowest to highest block number.
pub descriptions: Vec<BlockDescription>,
}
/// Message to the Approval Voting subsystem.
#[derive(Debug)]
pub enum ApprovalVotingMessage {
/// Check if the assignment is valid and can be accepted by our view of the protocol.
/// Should not be sent unless the block hash is known.
CheckAndImportAssignment(
IndirectAssignmentCert,
CandidateIndex,
oneshot::Sender<AssignmentCheckResult>,
),
/// Check if the approval vote is valid and can be accepted by our view of the
/// protocol.
///
/// Should not be sent unless the block hash within the indirect vote is known.
CheckAndImportApproval(IndirectSignedApprovalVote, oneshot::Sender<ApprovalCheckResult>),
/// Returns the highest possible ancestor hash of the provided block hash which is
/// acceptable to vote on finality for.
/// The `BlockNumber` provided is the number of the block's ancestor which is the
/// earliest possible vote.
///
/// It can also return the same block hash, if that is acceptable to vote upon.
/// Return `None` if the input hash is unrecognized.
ApprovedAncestor(Hash, BlockNumber, oneshot::Sender<Option<HighestApprovedAncestorBlock>>),
/// Retrieve all available approval signatures for a candidate from approval-voting.
///
/// This message involves a linear search for candidates on each relay chain fork and also
/// requires calling into `approval-distribution`: Calls should be infrequent and bounded.
GetApprovalSignaturesForCandidate(
CandidateHash,
oneshot::Sender<HashMap<ValidatorIndex, ValidatorSignature>>,
),
}
/// Message to the Approval Distribution subsystem.
#[derive(Debug, derive_more::From)]
pub enum ApprovalDistributionMessage {
/// Notify the `ApprovalDistribution` subsystem about new blocks
/// and the candidates contained within them.
NewBlocks(Vec<BlockApprovalMeta>),
/// Distribute an assignment cert from the local validator. The cert is assumed
/// to be valid, relevant, and for the given relay-parent and validator index.
DistributeAssignment(IndirectAssignmentCert, CandidateIndex),
/// Distribute an approval vote for the local validator. The approval vote is assumed to be
/// valid, relevant, and the corresponding approval already issued.
/// If not, the subsystem is free to drop the message.
DistributeApproval(IndirectSignedApprovalVote),
/// An update from the network bridge.
#[from]
NetworkBridgeUpdate(NetworkBridgeEvent<net_protocol::ApprovalDistributionMessage>),
/// Get all approval signatures for all chains a candidate appeared in.
GetApprovalSignatures(
HashSet<(Hash, CandidateIndex)>,
oneshot::Sender<HashMap<ValidatorIndex, ValidatorSignature>>,
),
/// Approval checking lag update measured in blocks.
ApprovalCheckingLagUpdate(BlockNumber),
}
/// Message to the Gossip Support subsystem.
#[derive(Debug, derive_more::From)]
pub enum GossipSupportMessage {
/// Dummy constructor, so we can receive networking events.
#[from]
NetworkBridgeUpdate(NetworkBridgeEvent<net_protocol::GossipSupportNetworkMessage>),
}
/// Request introduction of a candidate into the prospective parachains subsystem.
#[derive(Debug, PartialEq, Eq, Clone)]
pub struct IntroduceCandidateRequest {
/// The para-id of the candidate.
pub candidate_para: ParaId,
/// The candidate receipt itself.
pub candidate_receipt: CommittedCandidateReceipt,
/// The persisted validation data of the candidate.
pub persisted_validation_data: PersistedValidationData,
}
/// A hypothetical candidate to be evaluated for frontier membership
/// in the prospective parachains subsystem.
///
/// Hypothetical candidates are either complete or incomplete.
/// Complete candidates have already had their (potentially heavy)
/// candidate receipt fetched, while incomplete candidates are simply
/// claims about properties that a fetched candidate would have.
///
/// Complete candidates can be evaluated more strictly than incomplete candidates.
#[derive(Debug, PartialEq, Eq, Clone)]
pub enum HypotheticalCandidate {
/// A complete candidate.
Complete {
/// The hash of the candidate.
candidate_hash: CandidateHash,
/// The receipt of the candidate.
receipt: Arc<CommittedCandidateReceipt>,
/// The persisted validation data of the candidate.
persisted_validation_data: PersistedValidationData,
},
/// An incomplete candidate.
Incomplete {
/// The claimed hash of the candidate.
candidate_hash: CandidateHash,
/// The claimed para-ID of the candidate.
candidate_para: ParaId,
/// The claimed head-data hash of the candidate.
parent_head_data_hash: Hash,
/// The claimed relay parent of the candidate.
candidate_relay_parent: Hash,
},
}
impl HypotheticalCandidate {
/// Get the `CandidateHash` of the hypothetical candidate.
pub fn candidate_hash(&self) -> CandidateHash {
match *self {
HypotheticalCandidate::Complete { candidate_hash, .. } => candidate_hash,
HypotheticalCandidate::Incomplete { candidate_hash, .. } => candidate_hash,
}
}
/// Get the `ParaId` of the hypothetical candidate.
pub fn candidate_para(&self) -> ParaId {
match *self {
HypotheticalCandidate::Complete { ref receipt, .. } => receipt.descriptor().para_id,
HypotheticalCandidate::Incomplete { candidate_para, .. } => candidate_para,
}
}
/// Get parent head data hash of the hypothetical candidate.
pub fn parent_head_data_hash(&self) -> Hash {
match *self {
HypotheticalCandidate::Complete { ref persisted_validation_data, .. } =>
persisted_validation_data.parent_head.hash(),
HypotheticalCandidate::Incomplete { parent_head_data_hash, .. } =>
parent_head_data_hash,
}
}
/// Get candidate's relay parent.
pub fn relay_parent(&self) -> Hash {
match *self {
HypotheticalCandidate::Complete { ref receipt, .. } =>
receipt.descriptor().relay_parent,
HypotheticalCandidate::Incomplete { candidate_relay_parent, .. } =>
candidate_relay_parent,
}
}
}
/// Request specifying which candidates are either already included
/// or might be included in the hypothetical frontier of fragment trees
/// under a given active leaf.
#[derive(Debug, PartialEq, Eq, Clone)]
pub struct HypotheticalFrontierRequest {
/// Candidates, in arbitrary order, which should be checked for
/// possible membership in fragment trees.
pub candidates: Vec<HypotheticalCandidate>,
/// Either a specific fragment tree to check, otherwise all.
pub fragment_tree_relay_parent: Option<Hash>,
/// Only return membership if all candidates in the path from the
/// root are backed.
pub backed_in_path_only: bool,
}
/// A request for the persisted validation data stored in the prospective
/// parachains subsystem.
#[derive(Debug)]
pub struct ProspectiveValidationDataRequest {
/// The para-id of the candidate.
pub para_id: ParaId,
/// The relay-parent of the candidate.
pub candidate_relay_parent: Hash,
/// The parent head-data hash.
pub parent_head_data_hash: Hash,
}
/// Indicates the relay-parents whose fragment tree a candidate
/// is present in and the depths of that tree the candidate is present in.
pub type FragmentTreeMembership = Vec<(Hash, Vec<usize>)>;
/// Messages sent to the Prospective Parachains subsystem.
#[derive(Debug)]
pub enum ProspectiveParachainsMessage {
/// Inform the Prospective Parachains Subsystem of a new candidate.
///
/// The response sender accepts the candidate membership, which is the existing
/// membership of the candidate if it was already known.
IntroduceCandidate(IntroduceCandidateRequest, oneshot::Sender<FragmentTreeMembership>),
/// Inform the Prospective Parachains Subsystem that a previously introduced candidate
/// has been seconded. This requires that the candidate was successfully introduced in
/// the past.
CandidateSeconded(ParaId, CandidateHash),
/// Inform the Prospective Parachains Subsystem that a previously introduced candidate
/// has been backed. This requires that the candidate was successfully introduced in
/// the past.
CandidateBacked(ParaId, CandidateHash),
/// Get a backable candidate hash along with its relay parent for the given parachain,
/// under the given relay-parent hash, which is a descendant of the given candidate hashes.
/// Returns `None` on the channel if no such candidate exists.
GetBackableCandidate(
Hash,
ParaId,
Vec<CandidateHash>,
oneshot::Sender<Option<(CandidateHash, Hash)>>,
),
/// Get the hypothetical frontier membership of candidates with the given properties
/// under the specified active leaves' fragment trees.
///
/// For any candidate which is already known, this returns the depths the candidate
/// occupies.
GetHypotheticalFrontier(
HypotheticalFrontierRequest,
oneshot::Sender<Vec<(HypotheticalCandidate, FragmentTreeMembership)>>,
),
/// Get the membership of the candidate in all fragment trees.
GetTreeMembership(ParaId, CandidateHash, oneshot::Sender<FragmentTreeMembership>),
/// Get the minimum accepted relay-parent number for each para in the fragment tree
/// for the given relay-chain block hash.
///
/// That is, if the block hash is known and is an active leaf, this returns the
/// minimum relay-parent block number in the same branch of the relay chain which
/// is accepted in the fragment tree for each para-id.
///
/// If the block hash is not an active leaf, this will return an empty vector.
///
/// Para-IDs which are omitted from this list can be assumed to have no
/// valid candidate relay-parents under the given relay-chain block hash.
///
/// Para-IDs are returned in no particular order.
GetMinimumRelayParents(Hash, oneshot::Sender<Vec<(ParaId, BlockNumber)>>),
/// Get the validation data of some prospective candidate. The candidate doesn't need
/// to be part of any fragment tree, but this only succeeds if the parent head-data and
/// relay-parent are part of some fragment tree.
GetProspectiveValidationData(
ProspectiveValidationDataRequest,
oneshot::Sender<Option<PersistedValidationData>>,
),
}