Fast sync (#8884)

* State sync

* Importing state fixes

* Bugfixes

* Sync with proof

* Status reporting

* Unsafe sync mode

* Sync test

* Cleanup

* Apply suggestions from code review

Co-authored-by: cheme <emericchevalier.pro@gmail.com>
Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>

* set_genesis_storage

* Extract keys from range proof

* Detect iter completion

* Download and import bodies with fast sync

* Replaced meta updates tuple with a struct

* Fixed reverting finalized state

* Reverted timeout

* Typo

* Doc

* Doc

* Fixed light client test

* Fixed error handling

* Tweaks

* More UpdateMeta changes

* Rename convert_transaction

* Apply suggestions from code review

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>

* Apply suggestions from code review

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>

* Code review suggestions

* Fixed count handling

Co-authored-by: cheme <emericchevalier.pro@gmail.com>
Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>
Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>

Author: 4 people

Cargo.lock

@@ -41,6 +41,7 @@ use sp_consensus::BlockOrigin;
 use parking_lot::RwLock;
 
 pub use sp_state_machine::Backend as StateBackend;
+pub use sp_consensus::ImportedState;
 use std::marker::PhantomData;
 
 /// Extracts the state backend type for the given backend.
@@ -161,6 +162,10 @@ pub trait BlockImportOperation<Block: BlockT> {
 		update: TransactionForSB<Self::State, Block>,
 	) -> sp_blockchain::Result<()>;
 
+	/// Set genesis state. If `commit` is `false` the state is saved in memory, but is not written
+	/// to the database.
+	fn set_genesis_state(&mut self, storage: Storage, commit: bool) -> sp_blockchain::Result<Block::Hash>;
+
 	/// Inject storage data into the database replacing any existing data.
 	fn reset_storage(&mut self, storage: Storage) -> sp_blockchain::Result<Block::Hash>;
 

client/api/src/backend.rs

@@ -347,6 +347,11 @@ impl<Block: BlockT> HeaderBackend<Block> for Blockchain<Block> {
 			genesis_hash: storage.genesis_hash,
 			finalized_hash: storage.finalized_hash,
 			finalized_number: storage.finalized_number,
+			finalized_state: if storage.finalized_hash != Default::default() {
+				Some((storage.finalized_hash.clone(), storage.finalized_number))
+			} else {
+				None
+			},
 			number_leaves: storage.leaves.count()
 		}
 	}
@@ -528,6 +533,32 @@ pub struct BlockImportOperation<Block: BlockT> {
 	set_head: Option<BlockId<Block>>,
 }
 
+impl<Block: BlockT> BlockImportOperation<Block> where
+	Block::Hash: Ord,
+{
+	fn apply_storage(&mut self, storage: Storage, commit: bool) -> sp_blockchain::Result<Block::Hash> {
+		check_genesis_storage(&storage)?;
+
+		let child_delta = storage.children_default.iter()
+			.map(|(_storage_key, child_content)|
+				(
+					&child_content.child_info,
+					child_content.data.iter().map(|(k, v)| (k.as_ref(), Some(v.as_ref())))
+				)
+			);
+
+		let (root, transaction) = self.old_state.full_storage_root(
+			storage.top.iter().map(|(k, v)| (k.as_ref(), Some(v.as_ref()))),
+			child_delta,
+		);
+
+		if commit {
+			self.new_state = Some(transaction);
+		}
+		Ok(root)
+	}
+}
+
 impl<Block: BlockT> backend::BlockImportOperation<Block> for BlockImportOperation<Block> where
 	Block::Hash: Ord,
 {
@@ -569,24 +600,12 @@ impl<Block: BlockT> backend::BlockImportOperation<Block> for BlockImportOperatio
 		Ok(())
 	}
 
-	fn reset_storage(&mut self, storage: Storage) -> sp_blockchain::Result<Block::Hash> {
-		check_genesis_storage(&storage)?;
-
-		let child_delta = storage.children_default.iter()
-			.map(|(_storage_key, child_content)|
-				 (
-					 &child_content.child_info,
-					 child_content.data.iter().map(|(k, v)| (k.as_ref(), Some(v.as_ref())))
-				 )
-			);
-
-		let (root, transaction) = self.old_state.full_storage_root(
-			storage.top.iter().map(|(k, v)| (k.as_ref(), Some(v.as_ref()))),
-			child_delta,
-		);
+	fn set_genesis_state(&mut self, storage: Storage, commit: bool) -> sp_blockchain::Result<Block::Hash> {
+		self.apply_storage(storage, commit)
+	}
 
-		self.new_state = Some(transaction);
-		Ok(root)
+	fn reset_storage(&mut self, storage: Storage) -> sp_blockchain::Result<Block::Hash> {
+		self.apply_storage(storage, true)
 	}
 
 	fn insert_aux<I>(&mut self, ops: I) -> sp_blockchain::Result<()>
@@ -806,12 +825,12 @@ impl<Block: BlockT> backend::RemoteBackend<Block> for Backend<Block> where Block
 /// Check that genesis storage is valid.
 pub fn check_genesis_storage(storage: &Storage) -> sp_blockchain::Result<()> {
 	if storage.top.iter().any(|(k, _)| well_known_keys::is_child_storage_key(k)) {
-		return Err(sp_blockchain::Error::GenesisInvalid.into());
+		return Err(sp_blockchain::Error::InvalidState.into());
 	}
 
 	if storage.children_default.keys()
 		.any(|child_key| !well_known_keys::is_child_storage_key(&child_key)) {
-			return Err(sp_blockchain::Error::GenesisInvalid.into());
+			return Err(sp_blockchain::Error::InvalidState.into());
 	}
 
 	Ok(())

client/api/src/in_mem.rs

@@ -41,6 +41,7 @@ pub use proof_provider::*;
 pub use sp_blockchain::HeaderBackend;
 
 pub use sp_state_machine::{StorageProof, ExecutionStrategy};
+pub use sp_storage::{StorageData, StorageKey, PrefixedStorageKey, ChildInfo};
 
 /// Usage Information Provider interface
 ///

client/api/src/lib.rs

@@ -70,4 +70,31 @@ pub trait ProofProvider<Block: BlockT> {
 		storage_key: Option<&PrefixedStorageKey>,
 		key: &StorageKey,
 	) -> sp_blockchain::Result<ChangesProof<Block::Header>>;
+
+	/// Given a `BlockId` iterate over all storage values starting at `start_key` exclusively,
+	/// building proofs until size limit is reached. Returns combined proof and the number of collected keys.
+	fn read_proof_collection(
+		&self,
+		id: &BlockId<Block>,
+		start_key: &[u8],
+		size_limit: usize,
+	) -> sp_blockchain::Result<(StorageProof, u32)>;
+
+	/// Given a `BlockId` iterate over all storage values starting at `start_key`.
+	/// Returns collected keys and values.
+	fn storage_collection(
+		&self,
+		id: &BlockId<Block>,
+		start_key: &[u8],
+		size_limit: usize,
+	) -> sp_blockchain::Result<Vec<(Vec<u8>, Vec<u8>)>>;
+
+	/// Verify read storage proof for a set of keys.
+	/// Returns collected key-value pairs and a flag indicating if iteration is complete.
+	fn verify_range_proof(
+		&self,
+		root: Block::Hash,
+		proof: StorageProof,
+		start_key: &[u8],
+	) -> sp_blockchain::Result<(Vec<(Vec<u8>, Vec<u8>)>, bool)>;
 }

client/api/src/proof_provider.rs

@@ -69,6 +69,7 @@ impl<Block: BlockT> HeaderBackend<Block> for TestApi {
 			finalized_number: Zero::zero(),
 			genesis_hash: Default::default(),
 			number_leaves: Default::default(),
+			finalized_state: None,
 		}
 	}
 

client/authority-discovery/src/worker/tests.rs

@@ -232,6 +232,30 @@ arg_enum! {
 	}
 }
 
+arg_enum! {
+	/// Syncing mode.
+	#[allow(missing_docs)]
+	#[derive(Debug, Clone, Copy)]
+	pub enum SyncMode {
+		// Full sync. Donwnload end verify all blocks.
+		Full,
+		// Download blocks without executing them. Download latest state with proofs.
+		Fast,
+		// Download blocks without executing them. Download latest state without proofs.
+		FastUnsafe,
+	}
+}
+
+impl Into<sc_network::config::SyncMode> for SyncMode {
+	fn into(self) -> sc_network::config::SyncMode {
+		match self {
+			SyncMode::Full => sc_network::config::SyncMode::Full,
+			SyncMode::Fast => sc_network::config::SyncMode::Fast { skip_proofs: false },
+			SyncMode::FastUnsafe => sc_network::config::SyncMode::Fast { skip_proofs: true },
+		}
+	}
+}
+
 /// Default value for the `--execution-syncing` parameter.
 pub const DEFAULT_EXECUTION_SYNCING: ExecutionStrategy = ExecutionStrategy::NativeElseWasm;
 /// Default value for the `--execution-import-block` parameter.

client/cli/src/arg_enums.rs

@@ -17,6 +17,7 @@
 // along with this program. If not, see <https://www.gnu.org/licenses/>.
 
 use crate::params::node_key_params::NodeKeyParams;
+use crate::arg_enums::SyncMode;
 use sc_network::{
 	config::{NetworkConfiguration, NodeKeyConfig, NonReservedPeerMode, SetConfig, TransportConfig},
 	multiaddr::Protocol,
@@ -125,6 +126,13 @@ pub struct NetworkParams {
 	/// Join the IPFS network and serve transactions over bitswap protocol.
 	#[structopt(long)]
 	pub ipfs_server: bool,
+
+	/// Blockchain syncing mode.
+	/// Full - Download and validate full blockchain history (Default).
+	/// Fast - Download blocks and the latest state only.
+	/// FastUnsafe - Same as Fast, but do skips downloading state proofs.
+	#[structopt(long, default_value = "Full")]
+	pub sync: SyncMode,
 }
 
 impl NetworkParams {
@@ -218,6 +226,7 @@ impl NetworkParams {
 			kademlia_disjoint_query_paths: self.kademlia_disjoint_query_paths,
 			yamux_window_size: None,
 			ipfs_server: self.ipfs_server,
+			sync_mode: self.sync.into(),
 		}
 	}
 }

client/cli/src/params/network_params.rs

@@ -42,7 +42,7 @@ use codec::{Encode, Decode, Codec};
 
 use sp_consensus::{
 	BlockImport, Environment, Proposer, CanAuthorWith, ForkChoiceStrategy, BlockImportParams,
-	BlockOrigin, Error as ConsensusError, SelectChain,
+	BlockOrigin, Error as ConsensusError, SelectChain, StateAction,
 };
 use sc_client_api::{backend::AuxStore, BlockOf, UsageProvider};
 use sp_blockchain::{Result as CResult, ProvideCache, HeaderBackend};
@@ -421,7 +421,9 @@ where
 			let mut import_block = BlockImportParams::new(BlockOrigin::Own, header);
 			import_block.post_digests.push(signature_digest_item);
 			import_block.body = Some(body);
-			import_block.storage_changes = Some(storage_changes);
+			import_block.state_action = StateAction::ApplyChanges(
+				sp_consensus::StorageChanges::Changes(storage_changes)
+			);
 			import_block.fork_choice = Some(ForkChoiceStrategy::LongestChain);
 
 			Ok(import_block)

client/consensus/aura/src/lib.rs

@@ -101,6 +101,7 @@ use sp_consensus::{
 	import_queue::{BasicQueue, CacheKeyId, DefaultImportQueue, Verifier},
 	BlockCheckParams, BlockImport, BlockImportParams, BlockOrigin, Environment,
 	Error as ConsensusError, ForkChoiceStrategy, Proposer, SelectChain, SlotData,
+	StateAction,
 };
 use sp_consensus_babe::inherents::BabeInherentData;
 use sp_consensus_slots::Slot;
@@ -790,7 +791,9 @@ where
 			let mut import_block = BlockImportParams::new(BlockOrigin::Own, header);
 			import_block.post_digests.push(digest_item);
 			import_block.body = Some(body);
-			import_block.storage_changes = Some(storage_changes);
+			import_block.state_action = StateAction::ApplyChanges(
+				sp_consensus::StorageChanges::Changes(storage_changes)
+			);
 			import_block.intermediates.insert(
 				Cow::from(INTERMEDIATE_KEY),
 				Box::new(BabeIntermediate::<B> { epoch_descriptor }) as Box<_>,
@@ -1295,7 +1298,12 @@ impl<Block, Client, Inner> BlockImport<Block> for BabeBlockImport<Block, Client,
 		// early exit if block already in chain, otherwise the check for
 		// epoch changes will error when trying to re-import an epoch change
 		match self.client.status(BlockId::Hash(hash)) {
-			Ok(sp_blockchain::BlockStatus::InChain) => return Ok(ImportResult::AlreadyInChain),
+			Ok(sp_blockchain::BlockStatus::InChain) => {
+				// When re-importing existing block strip away intermediates.
+				let _ = block.take_intermediate::<BabeIntermediate<Block>>(INTERMEDIATE_KEY)?;
+				block.fork_choice = Some(ForkChoiceStrategy::Custom(false));
+				return self.inner.import_block(block, new_cache).await.map_err(Into::into)
+			},
 			Ok(sp_blockchain::BlockStatus::Unknown) => {},
 			Err(e) => return Err(ConsensusError::ClientImport(e.to_string())),
 		}