babe: secondary blocks with VRF (#5501)

* babe: secondary blocks with VRF

* Fix node runtime compile

* Fix test-utils runtime interface

* Fix babe tests

* typo: v == 2

* babe: support online configuration upgrades

* Fix rpc tests

* Fix runtime version tests

* Switch to use NextConfigDescriptor instead of changing runtime interface

* Fix tests

* epoch-changes: map function that allows converting with different epoch types

* Add migration script for the epoch config change

* Fix docs for PrimaryAndSecondaryVRFSlots

* Add docs of `SecondaryVRF` in babe crate

* babe-primitives: Secondary -> SecondaryPlain

* babe-client: Secondary -> SecondaryPlain

* Fix migration tests

* test-utils-runtime: Secondary -> SecondaryPlain

* Fix missing name change in test-utils-runtime

* Fix migration: Epoch should be EpochV0

* Update client/consensus/babe/src/lib.rs

Co-Authored-By: André Silva <123550+andresilva@users.noreply.github.com>

* Fix new epochChanges version

* Fix babe-primitives naming changes

* Fix merge issues in babe-client

Co-authored-by: André Silva <123550+andresilva@users.noreply.github.com>
Co-authored-by: André Silva <andre.beat@gmail.com>

substrate/primitives/consensus/babe/src/digests.rs

@@ -65,7 +65,7 @@ impl TryFrom<RawPrimaryPreDigest> for PrimaryPreDigest {
 
 /// BABE secondary slot assignment pre-digest.
 #[derive(Clone, RuntimeDebug, Encode, Decode)]
-pub struct SecondaryPreDigest {
+pub struct SecondaryPlainPreDigest {
 	/// Authority index
 	///
 	/// This is not strictly-speaking necessary, since the secondary slots
@@ -77,6 +77,37 @@ pub struct SecondaryPreDigest {
 	pub slot_number: SlotNumber,
 }
 
+/// BABE secondary deterministic slot assignment with VRF outputs.
+#[derive(Clone, RuntimeDebug, Encode, Decode)]
+pub struct RawSecondaryVRFPreDigest<VRFOutput=schnorrkel::RawVRFOutput, VRFProof=schnorrkel::RawVRFProof> {
+	/// Authority index
+	pub authority_index: super::AuthorityIndex,
+	/// Slot number
+	pub slot_number: SlotNumber,
+	/// VRF output
+	pub vrf_output: VRFOutput,
+	/// VRF proof
+	pub vrf_proof: VRFProof,
+}
+
+#[cfg(feature = "std")]
+/// BABE secondary slot assignment with VRF outputs pre-digest, for std environment.
+pub type SecondaryVRFPreDigest = RawSecondaryVRFPreDigest<schnorrkel::VRFOutput, schnorrkel::VRFProof>;
+
+#[cfg(feature = "std")]
+impl TryFrom<RawSecondaryVRFPreDigest> for SecondaryVRFPreDigest {
+	type Error = SignatureError;
+
+	fn try_from(raw: RawSecondaryVRFPreDigest) -> Result<SecondaryVRFPreDigest, SignatureError> {
+		Ok(SecondaryVRFPreDigest {
+			authority_index: raw.authority_index,
+			slot_number: raw.slot_number,
+			vrf_output: raw.vrf_output.try_into()?,
+			vrf_proof: raw.vrf_proof.try_into()?,
+		})
+	}
+}
+
 /// A BABE pre-runtime digest. This contains all data required to validate a
 /// block and for the BABE runtime module. Slots can be assigned to a primary
 /// (VRF based) and to a secondary (slot number based).
@@ -87,7 +118,10 @@ pub enum RawPreDigest<VRFOutput=schnorrkel::RawVRFOutput, VRFProof=schnorrkel::R
 	Primary(RawPrimaryPreDigest<VRFOutput, VRFProof>),
 	/// A secondary deterministic slot assignment.
 	#[codec(index = "2")]
-	Secondary(SecondaryPreDigest),
+	SecondaryPlain(SecondaryPlainPreDigest),
+	/// A secondary deterministic slot assignment with VRF outputs.
+	#[codec(index = "3")]
+	SecondaryVRF(RawSecondaryVRFPreDigest<VRFOutput, VRFProof>),
 }
 
 #[cfg(feature = "std")]
@@ -99,7 +133,8 @@ impl<VRFOutput, VRFProof> RawPreDigest<VRFOutput, VRFProof> {
 	pub fn authority_index(&self) -> AuthorityIndex {
 		match self {
 			RawPreDigest::Primary(primary) => primary.authority_index,
-			RawPreDigest::Secondary(secondary) => secondary.authority_index,
+			RawPreDigest::SecondaryPlain(secondary) => secondary.authority_index,
+			RawPreDigest::SecondaryVRF(secondary) => secondary.authority_index,
 		}
 	}
 
@@ -107,7 +142,8 @@ impl<VRFOutput, VRFProof> RawPreDigest<VRFOutput, VRFProof> {
 	pub fn slot_number(&self) -> SlotNumber {
 		match self {
 			RawPreDigest::Primary(primary) => primary.slot_number,
-			RawPreDigest::Secondary(secondary) => secondary.slot_number,
+			RawPreDigest::SecondaryPlain(secondary) => secondary.slot_number,
+			RawPreDigest::SecondaryVRF(secondary) => secondary.slot_number,
 		}
 	}
 
@@ -116,7 +152,7 @@ impl<VRFOutput, VRFProof> RawPreDigest<VRFOutput, VRFProof> {
 	pub fn added_weight(&self) -> crate::BabeBlockWeight {
 		match self {
 			RawPreDigest::Primary(_) => 1,
-			RawPreDigest::Secondary(_) => 0,
+			RawPreDigest::SecondaryPlain(_) | RawPreDigest::SecondaryVRF(_) => 0,
 		}
 	}
 }
@@ -128,7 +164,8 @@ impl TryFrom<RawPreDigest> for PreDigest {
 	fn try_from(raw: RawPreDigest) -> Result<PreDigest, SignatureError> {
 		Ok(match raw {
 			RawPreDigest::Primary(primary) => PreDigest::Primary(primary.try_into()?),
-			RawPreDigest::Secondary(secondary) => PreDigest::Secondary(secondary),
+			RawPreDigest::SecondaryPlain(secondary) => PreDigest::SecondaryPlain(secondary),
+			RawPreDigest::SecondaryVRF(secondary) => PreDigest::SecondaryVRF(secondary.try_into()?),
 		})
 	}
 }