Grandpa warp sync request-response protocol (#7711)

* Made a start

* So the proof between authority set is phragmen one, this is crazy big,
or is there some signing of the result : that is the storage key, damn?

* ok getting from header digest seems doable.

* for testing

* get set id from storage directly (should use runtime to handler change).

* move test to init

* correct auth key

* fix iteration

* Correct proof content

* actually update block number.

* actually check last justif against its header

* justification relation to new authorities through header hash check is
needed here. This assumes the hash from header is calculated.

* Few changes

* Connected up cheme's branch

* Clean up

* Move things around a bit so that adding the grandpa warp sync request response protocol happens in the node code

* Nits

* Changes to comments

* Cheme changes

* Remove todos and test compile.

* Rename _authority_ related proof function to _warp_sync_ .

* Update client/grandpa-warp-sync/src/lib.rs

quick fix

* Put the warp sync request response protocol behind a feature flag because we dont' need it on a light client.

* Update client/grandpa-warp-sync/src/lib.rs

Quick fix

* Update Cargo.lock

* Adding test, comment on limitation related to 'delay', this could
be implemented but with a cost.

* Set between a delay override last fragment.

* Check for pending authority set change at start.

* adjust index

* custom cache is not a good idea.

* Use a simple cache instead.

* restore broken indentation

* Address crate rename

* Merge conflict badly resolved, sorry

Co-authored-by: cheme <[email protected]>
Co-authored-by: Pierre Krieger <[email protected]>

Cargo.toml

@@ -37,6 +37,7 @@ members = [
 	"client/executor/wasmi",
 	"client/executor/wasmtime",
 	"client/finality-grandpa",
+	"client/finality-grandpa-warp-sync",
 	"client/informant",
 	"client/keystore",
 	"client/light",

bin/node/cli/Cargo.toml

@@ -74,6 +74,7 @@ sc-service = { version = "0.8.0", default-features = false, path = "../../../cli
 sc-tracing = { version = "2.0.0", path = "../../../client/tracing" }
 sc-telemetry = { version = "2.0.0", path = "../../../client/telemetry" }
 sc-authority-discovery = { version = "0.8.0",  path = "../../../client/authority-discovery" }
+sc-finality-grandpa-warp-sync = { version = "0.8.0", path = "../../../client/finality-grandpa-warp-sync", optional = true }
 
 # frame dependencies
 pallet-indices = { version = "2.0.0", path = "../../../frame/indices" }
@@ -151,6 +152,7 @@ cli = [
 	"frame-benchmarking-cli",
 	"substrate-frame-cli",
 	"sc-service/db",
+	"sc-finality-grandpa-warp-sync",
 	"structopt",
 	"substrate-build-script-utils",
 ]

bin/node/cli/src/service.rs

@@ -194,6 +194,11 @@ pub fn new_full_base(
 
 	config.network.extra_sets.push(grandpa::grandpa_peers_set_config());
 
+	#[cfg(feature = "cli")]
+	config.network.request_response_protocols.push(sc_finality_grandpa_warp_sync::request_response_config_for_chain(
+		&config, task_manager.spawn_handle(), backend.clone(),
+	));
+
 	let (network, network_status_sinks, system_rpc_tx, network_starter) =
 		sc_service::build_network(sc_service::BuildNetworkParams {
 			config: &config,

client/finality-grandpa-warp-sync/Cargo.toml

@@ -0,0 +1,28 @@
+[package]
+description = "A request-response protocol for handling grandpa warp sync requests"
+name = "sc-finality-grandpa-warp-sync"
+version = "0.8.0"
+license = "GPL-3.0-or-later WITH Classpath-exception-2.0"
+authors = ["Parity Technologies <[email protected]>"]
+edition = "2018"
+publish = false
+homepage = "https://substrate.dev"
+repository = "https://github.com/paritytech/substrate/"
+
+[package.metadata.docs.rs]
+targets = ["x86_64-unknown-linux-gnu"]
+
+[dependencies]
+sc-network = { version = "0.8.0", path = "../network" }
+sc-finality-grandpa = { version = "0.8.0", path = "../finality-grandpa" }
+sp-runtime = { version = "2.0.0", path = "../../primitives/runtime" }
+sp-blockchain = { version = "2.0.0", path = "../../primitives/blockchain" }
+sc-client-api = { version = "2.0.0", path = "../api" }
+sc-service = { version = "0.8.0", path = "../service" }
+futures = "0.3.8"
+log = "0.4.11"
+derive_more = "0.99.11"
+codec = { package = "parity-scale-codec", version = "1.3.5" }
+prost = "0.6.1"
+num-traits = "0.2.14"
+parking_lot = "0.11.1"