Fix key collision for child trie (#4162)

* In progress, runtime io must switch to future proof root +
child_specific (unique id) + u32 type.

* Switch interface, sr-io seems ok, rpc could use similar interface to
sr-io, genesis json broken if there is child trie in existing encoding
genesis.

* test from previous implementation.

* fix proving test.

* Restore Keyspacedb from other branch, only apply to child trie.

* Removing unneeded child_info from child root (child info are stored
if things changed, otherwhise the root does not change).

* Switch rpc to use same format as ext: more future proof.

* use root from child info for trie backend essence.

* Breaking long lines.

* Update doc and clean pr a bit.

* fix error type

* Restore removed doc on merge and update sr-io doc.

* Switch child storage api to use directly unique id, if managed id
where to be put in place, the api will change at this time.

* Clean deprecated host interface from child.

* Removing assertion on child info (can fail depending on root
memoization).

* merging child info in the overlay when possible.

* child iteration by prefix using child_info.

* Using ChainInfo in frame support. ChainInfo gets redesign to avoid
buffers allocation on every calls.

* Add length of root to the data of child info.

* comments

* Encode compact.

* Remove child info with root.

* Fix try_update condition.

* Comment Ext child root caching.

* Replace tuples by struct with field

* remove StorageTuple alias.

* Fix doc tests, and remove StorageOverlay and ChildStorageOverlay
aliases.

substrate/client/network/src/chain.rs

@@ -23,7 +23,8 @@ use consensus::{BlockImport, BlockStatus, Error as ConsensusError};
 use sp_runtime::traits::{Block as BlockT, Header as HeaderT};
 use sp_runtime::generic::{BlockId};
 use sp_runtime::Justification;
-use primitives::{H256, Blake2Hasher, storage::StorageKey};
+use primitives::{H256, Blake2Hasher};
+use primitives::storage::{StorageKey, ChildInfo};
 
 /// Local client abstraction for the network.
 pub trait Client<Block: BlockT>: Send + Sync {
@@ -57,6 +58,7 @@ pub trait Client<Block: BlockT>: Send + Sync {
 		&self,
 		block: &Block::Hash,
 		storage_key: &[u8],
+		child_info: ChildInfo,
 		keys: &[Vec<u8>],
 	) -> Result<StorageProof, Error>;
 
@@ -135,10 +137,11 @@ impl<B, E, Block, RA> Client<Block> for SubstrateClient<B, E, Block, RA> where
 		&self,
 		block: &Block::Hash,
 		storage_key: &[u8],
+		child_info: ChildInfo,
 		keys: &[Vec<u8>],
 	) -> Result<StorageProof, Error> {
 		(self as &SubstrateClient<B, E, Block, RA>)
-			.read_child_proof(&BlockId::Hash(block.clone()), storage_key, keys)
+			.read_child_proof(&BlockId::Hash(block.clone()), storage_key, child_info, keys)
 	}
 
 	fn execution_proof(&self, block: &Block::Hash, method: &str, data: &[u8]) -> Result<(Vec<u8>, StorageProof), Error> {

substrate/client/network/src/protocol.rs

@@ -24,7 +24,7 @@ use libp2p::{Multiaddr, PeerId};
 use libp2p::core::{ConnectedPoint, nodes::Substream, muxing::StreamMuxerBox};
 use libp2p::swarm::{ProtocolsHandler, IntoProtocolsHandler};
 use libp2p::swarm::{NetworkBehaviour, NetworkBehaviourAction, PollParameters};
-use primitives::storage::StorageKey;
+use primitives::storage::{StorageKey, ChildInfo};
 use consensus::{
 	BlockOrigin,
 	block_validation::BlockAnnounceValidator,
@@ -238,12 +238,16 @@ impl<'a, B: BlockT> LightDispatchNetwork<B> for LightDispatchIn<'a> {
 		id: RequestId,
 		block: <B as BlockT>::Hash,
 		storage_key: Vec<u8>,
+		child_info: Vec<u8>,
+		child_type: u32,
 		keys: Vec<Vec<u8>>,
 	) {
 		let message: Message<B> = message::generic::Message::RemoteReadChildRequest(message::RemoteReadChildRequest {
 			id,
 			block,
 			storage_key,
+			child_info,
+			child_type,
 			keys,
 		});
 
@@ -1554,23 +1558,37 @@ impl<B: BlockT, S: NetworkSpecialization<B>, H: ExHashT> Protocol<B, S, H> {
 
 		trace!(target: "sync", "Remote read child request {} from {} ({} {} at {})",
 			request.id, who, request.storage_key.to_hex::<String>(), keys_str(), request.block);
-		let proof = match self.context_data.chain.read_child_proof(
-			&request.block,
-			&request.storage_key,
-			&request.keys,
-		) {
-			Ok(proof) => proof,
-			Err(error) => {
-				trace!(target: "sync", "Remote read child request {} from {} ({} {} at {}) failed with: {}",
-					request.id,
-					who,
-					request.storage_key.to_hex::<String>(),
-					keys_str(),
-					request.block,
-					error
-				);
-				StorageProof::empty()
+		let proof = if let Some(child_info) = ChildInfo::resolve_child_info(request.child_type, &request.child_info[..]) {
+			match self.context_data.chain.read_child_proof(
+				&request.block,
+				&request.storage_key,
+				child_info,
+				&request.keys,
+			) {
+				Ok(proof) => proof,
+				Err(error) => {
+					trace!(target: "sync", "Remote read child request {} from {} ({} {} at {}) failed with: {}",
+						request.id,
+						who,
+						request.storage_key.to_hex::<String>(),
+						keys_str(),
+						request.block,
+						error
+					);
+					StorageProof::empty()
+				}
 			}
+		} else {
+			trace!(target: "sync", "Remote read child request {} from {} ({} {} at {}) failed with: {}",
+				request.id,
+				who,
+				request.storage_key.to_hex::<String>(),
+				keys_str(),
+				request.block,
+				"invalid child info and type",
+			);
+
+			StorageProof::empty()
 		};
 		self.send_message(
 			&who,

substrate/client/network/src/protocol/light_dispatch.rs

@@ -69,6 +69,8 @@ pub trait LightDispatchNetwork<B: BlockT> {
 		id: RequestId,
 		block: <B as BlockT>::Hash,
 		storage_key: Vec<u8>,
+		child_info: Vec<u8>,
+		child_type: u32,
 		keys: Vec<Vec<u8>>,
 	);
 
@@ -622,6 +624,8 @@ impl<Block: BlockT> Request<Block> {
 					self.id,
 					data.block,
 					data.storage_key.clone(),
+					data.child_info.clone(),
+					data.child_type,
 					data.keys.clone(),
 				),
 			RequestData::RemoteCall(ref data, _) =>
@@ -677,6 +681,7 @@ pub mod tests {
 	use std::sync::Arc;
 	use std::time::Instant;
 	use futures::{Future, sync::oneshot};
+	use primitives::storage::ChildInfo;
 	use sp_runtime::traits::{Block as BlockT, NumberFor, Header as HeaderT};
 	use sp_blockchain::{Error as ClientError, Result as ClientResult};
 	use client_api::{FetchChecker, RemoteHeaderRequest,
@@ -808,7 +813,7 @@ pub mod tests {
 		fn send_header_request(&mut self, _: &PeerId, _: RequestId, _: <<B as BlockT>::Header as HeaderT>::Number) {}
 		fn send_read_request(&mut self, _: &PeerId, _: RequestId, _: <B as BlockT>::Hash, _: Vec<Vec<u8>>) {}
 		fn send_read_child_request(&mut self, _: &PeerId, _: RequestId, _: <B as BlockT>::Hash, _: Vec<u8>,
-			_: Vec<Vec<u8>>) {}
+			_: Vec<u8>, _: u32, _: Vec<Vec<u8>>) {}
 		fn send_call_request(&mut self, _: &PeerId, _: RequestId, _: <B as BlockT>::Hash, _: String, _: Vec<u8>) {}
 		fn send_changes_request(&mut self, _: &PeerId, _: RequestId, _: <B as BlockT>::Hash, _: <B as BlockT>::Hash,
 			_: <B as BlockT>::Hash, _: <B as BlockT>::Hash, _: Option<Vec<u8>>, _: Vec<u8>) {}
@@ -1027,10 +1032,14 @@ pub mod tests {
 		light_dispatch.on_connect(&mut network_interface, peer0.clone(), Roles::FULL, 1000);
 
 		let (tx, response) = oneshot::channel();
+		let child_info = ChildInfo::new_default(b"unique_id_1");
+		let (child_info, child_type) = child_info.info();
 		light_dispatch.add_request(&mut network_interface, RequestData::RemoteReadChild(RemoteReadChildRequest {
 			header: dummy_header(),
 			block: Default::default(),
 			storage_key: b":child_storage:sub".to_vec(),
+			child_info: child_info.to_vec(),
+			child_type,
 			keys: vec![b":key".to_vec()],
 			retry_count: None,
 		}, tx));

substrate/client/network/src/protocol/message.rs

@@ -368,6 +368,11 @@ pub mod generic {
 		pub block: H,
 		/// Child Storage key.
 		pub storage_key: Vec<u8>,
+		/// Child trie source information.
+		pub child_info: Vec<u8>,
+		/// Child type, its required to resolve `child_info`
+		/// content and choose child implementation.
+		pub child_type: u32,
 		/// Storage key.
 		pub keys: Vec<Vec<u8>>,
 	}