Dispute distribution implementation (#3282)

* Dispute protocol. * Dispute distribution protocol. * Get network requests routed. * WIP: Basic dispute sender logic. * Basic validator determination logic. * WIP: Getting things to typecheck. * Slightly larger timeout. * More typechecking stuff. * Cleanup. * Finished most of the sending logic. * Handle active leaves updates - Cleanup dead disputes - Update sends for new sessions - Retry on errors * Pass sessions in already. * Startup dispute sending. * Provide incoming decoding facilities and use them in statement-distribution. * Relaxed runtime util requirements. We only need a `SubsystemSender` not a full `SubsystemContext`. * Better usability of incoming requests. Make it possible to consume stuff without clones. * Add basic receiver functionality. * Cleanup + fixes for sender. * One more sender fix. * Start receiver. * Make sure to send responses back. * WIP: Exposed authority discovery * Make tests pass. * Fully featured receiver. * Decrease cost of `NotAValidator`. * Make `RuntimeInfo` LRU cache size configurable. * Cache more sessions. * Fix collator protocol. * Disable metrics for now. * Make dispute-distribution a proper subsystem. * Fix naming. * Code style fixes. * Factored out 4x copied mock function. * WIP: Tests. * Whitespace cleanup. * Accessor functions. * More testing. * More Debug instances. * Fix busy loop. * Working tests. * More tests. * Cleanup. * Fix build. * Basic receiving test. * Non validator message gets dropped. * More receiving tests. * Test nested and subsequent imports. * Fix spaces. * Better formatted imports. * Import cleanup. * Metrics. * Message -> MuxedMessage * Message -> MuxedMessage * More review remarks. * Add missing metrics.rs. * Fix flaky test. * Dispute coordinator - deliver confirmations. * Send out `DisputeMessage` on issue local statement. * Unwire dispute distribution. * Review remarks. * Review remarks. * Better docs.
2026-07-24 20:35:41 +00:00 · 2021-07-09 04:29:53 +02:00
parent 20993b32b1
commit b5257b2407
52 changed files with 4040 additions and 407 deletions
@@ -0,0 +1,177 @@
+// Copyright 2021 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/>.
+
+use std::convert::TryInto;
+
+use parity_scale_codec::{Decode, Encode};
+
+use sp_application_crypto::AppKey;
+use sp_keystore::{CryptoStore, SyncCryptoStorePtr, Error as KeystoreError};
+
+use polkadot_primitives::v1::{CandidateHash, CandidateReceipt, DisputeStatement, InvalidDisputeStatementKind, SessionIndex, ValidDisputeStatementKind, ValidatorId, ValidatorIndex, ValidatorSignature};
+
+/// `DisputeMessage` and related types.
+mod message;
+pub use message::{DisputeMessage, UncheckedDisputeMessage, Error as DisputeMessageCheckError};
+
+/// A checked dispute statement from an associated validator.
+#[derive(Debug, Clone)]
+pub struct SignedDisputeStatement {
+	dispute_statement: DisputeStatement,
+	candidate_hash: CandidateHash,
+	validator_public: ValidatorId,
+	validator_signature: ValidatorSignature,
+	session_index: SessionIndex,
+}
+
+/// Tracked votes on candidates, for the purposes of dispute resolution.
+#[derive(Debug, Clone)]
+pub struct CandidateVotes {
+	/// The receipt of the candidate itself.
+	pub candidate_receipt: CandidateReceipt,
+	/// Votes of validity, sorted by validator index.
+	pub valid: Vec<(ValidDisputeStatementKind, ValidatorIndex, ValidatorSignature)>,
+	/// Votes of invalidity, sorted by validator index.
+	pub invalid: Vec<(InvalidDisputeStatementKind, ValidatorIndex, ValidatorSignature)>,
+}
+
+impl CandidateVotes {
+	/// Get the set of all validators who have votes in the set, ascending.
+	pub fn voted_indices(&self) -> Vec<ValidatorIndex> {
+		let mut v: Vec<_> = self.valid.iter().map(|x| x.1).chain(
+			self.invalid.iter().map(|x| x.1)
+		).collect();
+
+		v.sort();
+		v.dedup();
+
+		v
+	}
+}
+
+impl SignedDisputeStatement {
+	/// Create a new `SignedDisputeStatement`, which is only possible by checking the signature.
+	pub fn new_checked(
+		dispute_statement: DisputeStatement,
+		candidate_hash: CandidateHash,
+		session_index: SessionIndex,
+		validator_public: ValidatorId,
+		validator_signature: ValidatorSignature,
+	) -> Result<Self, ()> {
+		dispute_statement.check_signature(
+			&validator_public,
+			candidate_hash,
+			session_index,
+			&validator_signature,
+		).map(|_| SignedDisputeStatement {
+			dispute_statement,
+			candidate_hash,
+			validator_public,
+			validator_signature,
+			session_index,
+		})
+	}
+
+	/// Sign this statement with the given keystore and key. Pass `valid = true` to
+	/// indicate validity of the candidate, and `valid = false` to indicate invalidity.
+	pub async fn sign_explicit(
+		keystore: &SyncCryptoStorePtr,
+		valid: bool,
+		candidate_hash: CandidateHash,
+		session_index: SessionIndex,
+		validator_public: ValidatorId,
+	) -> Result<Option<Self>, KeystoreError> {
+		let dispute_statement = if valid {
+			DisputeStatement::Valid(ValidDisputeStatementKind::Explicit)
+		} else {
+			DisputeStatement::Invalid(InvalidDisputeStatementKind::Explicit)
+		};
+
+		let data = dispute_statement.payload_data(candidate_hash, session_index);
+		let signature = CryptoStore::sign_with(
+			&**keystore,
+			ValidatorId::ID,
+			&validator_public.clone().into(),
+			&data,
+		).await?;
+
+		let signature = match signature {
+			Some(sig) => sig.try_into().map_err(|_| KeystoreError::KeyNotSupported(ValidatorId::ID))?,
+			None => return Ok(None),
+		};
+
+		Ok(Some(Self {
+			dispute_statement,
+			candidate_hash,
+			validator_public,
+			validator_signature: signature,
+			session_index,
+		}))
+	}
+
+	/// Access the underlying dispute statement
+	pub fn statement(&self) -> &DisputeStatement {
+		&self.dispute_statement
+	}
+
+	/// Access the underlying candidate hash.
+	pub fn candidate_hash(&self) -> &CandidateHash {
+		&self.candidate_hash
+	}
+
+	/// Access the underlying validator public key.
+	pub fn validator_public(&self) -> &ValidatorId {
+		&self.validator_public
+	}
+
+	/// Access the underlying validator signature.
+	pub fn validator_signature(&self) -> &ValidatorSignature {
+		&self.validator_signature
+	}
+
+	/// Access the underlying session index.
+	pub fn session_index(&self) -> SessionIndex {
+		self.session_index
+	}
+}
+
+/// Any invalid vote (currently only explicit).
+#[derive(Clone, Encode, Decode, Debug)]
+pub struct InvalidDisputeVote {
+	/// The voting validator index.
+	pub validator_index: ValidatorIndex,
+
+	/// The validator signature, that can be verified when constructing a
+	/// `SignedDisputeStatement`.
+	pub signature: ValidatorSignature,
+
+	/// Kind of dispute statement.
+	pub kind: InvalidDisputeStatementKind,
+}
+
+/// Any valid vote (backing, approval, explicit).
+#[derive(Clone, Encode, Decode, Debug)]
+pub struct ValidDisputeVote {
+	/// The voting validator index.
+	pub validator_index: ValidatorIndex,
+
+	/// The validator signature, that can be verified when constructing a
+	/// `SignedDisputeStatement`.
+	pub signature: ValidatorSignature,
+
+	/// Kind of dispute statement.
+	pub kind: ValidDisputeStatementKind,
+}