sp-core: Rename VrfOutput to VrfPreOutput (#2534)

This will make more sense after
#2524 since the
schnorrkel type for VRF outputs is also renamed in the latest version.
Can be reviewed independently though.

Can be merged after #1577
so that there is less pain for @davxy.

---------

Co-authored-by: Bastian Köcher <git@kchr.de>

polkadot/node/core/approval-voting/src/approval_db/v2/migration_helpers.rs

@@ -18,7 +18,8 @@
 use super::*;
 use crate::backend::Backend;
 use polkadot_node_primitives::approval::v1::{
-	AssignmentCert, AssignmentCertKind, VrfOutput, VrfProof, VrfSignature, RELAY_VRF_MODULO_CONTEXT,
+	AssignmentCert, AssignmentCertKind, VrfPreOutput, VrfProof, VrfSignature,
+	RELAY_VRF_MODULO_CONTEXT,
 };
 use polkadot_node_subsystem_util::database::Database;
 use sp_application_crypto::sp_core::H256;
@@ -30,9 +31,12 @@ fn dummy_assignment_cert(kind: AssignmentCertKind) -> AssignmentCert {
 	let mut prng = rand_core::OsRng;
 	let keypair = schnorrkel::Keypair::generate_with(&mut prng);
 	let (inout, proof, _) = keypair.vrf_sign(ctx.bytes(msg));
-	let out = inout.to_output();
+	let preout = inout.to_output();
 
-	AssignmentCert { kind, vrf: VrfSignature { output: VrfOutput(out), proof: VrfProof(proof) } }
+	AssignmentCert {
+		kind,
+		vrf: VrfSignature { pre_output: VrfPreOutput(preout), proof: VrfProof(proof) },
+	}
 }
 
 fn make_block_entry_v1(

polkadot/node/core/approval-voting/src/criteria.rs

@@ -21,7 +21,9 @@ use parity_scale_codec::{Decode, Encode};
 use polkadot_node_primitives::approval::{
 	self as approval_types,
 	v1::{AssignmentCert, AssignmentCertKind, DelayTranche, RelayVRFStory},
-	v2::{AssignmentCertKindV2, AssignmentCertV2, CoreBitfield, VrfOutput, VrfProof, VrfSignature},
+	v2::{
+		AssignmentCertKindV2, AssignmentCertV2, CoreBitfield, VrfPreOutput, VrfProof, VrfSignature,
+	},
 };
 use polkadot_primitives::{
 	AssignmentId, AssignmentPair, CandidateHash, CoreIndex, GroupIndex, IndexedVec, SessionInfo,
@@ -459,7 +461,7 @@ fn compute_relay_vrf_modulo_assignments_v1(
 			let cert = AssignmentCert {
 				kind: AssignmentCertKind::RelayVRFModulo { sample: rvm_sample },
 				vrf: VrfSignature {
-					output: VrfOutput(vrf_in_out.to_output()),
+					pre_output: VrfPreOutput(vrf_in_out.to_output()),
 					proof: VrfProof(vrf_proof),
 				},
 			};
@@ -539,7 +541,7 @@ fn compute_relay_vrf_modulo_assignments_v2(
 				core_bitfield: assignment_bitfield.clone(),
 			},
 			vrf: VrfSignature {
-				output: VrfOutput(vrf_in_out.to_output()),
+				pre_output: VrfPreOutput(vrf_in_out.to_output()),
 				proof: VrfProof(vrf_proof),
 			},
 		};
@@ -574,7 +576,7 @@ fn compute_relay_vrf_delay_assignments(
 		let cert = AssignmentCertV2 {
 			kind: AssignmentCertKindV2::RelayVRFDelay { core_index: core },
 			vrf: VrfSignature {
-				output: VrfOutput(vrf_in_out.to_output()),
+				pre_output: VrfPreOutput(vrf_in_out.to_output()),
 				proof: VrfProof(vrf_proof),
 			},
 		};
@@ -689,7 +691,7 @@ pub(crate) fn check_assignment_cert(
 		}
 	}
 
-	let vrf_output = &assignment.vrf.output;
+	let vrf_pre_output = &assignment.vrf.pre_output;
 	let vrf_proof = &assignment.vrf.proof;
 	let first_claimed_core_index =
 		claimed_core_indices.first_one().expect("Checked above; qed") as u32;
@@ -704,7 +706,7 @@ pub(crate) fn check_assignment_cert(
 			let (vrf_in_out, _) = public
 				.vrf_verify_extra(
 					relay_vrf_modulo_transcript_v2(relay_vrf_story),
-					&vrf_output.0,
+					&vrf_pre_output.0,
 					&vrf_proof.0,
 					assigned_cores_transcript(core_bitfield),
 				)
@@ -753,7 +755,7 @@ pub(crate) fn check_assignment_cert(
 			let (vrf_in_out, _) = public
 				.vrf_verify_extra(
 					relay_vrf_modulo_transcript_v1(relay_vrf_story, *sample),
-					&vrf_output.0,
+					&vrf_pre_output.0,
 					&vrf_proof.0,
 					assigned_core_transcript(CoreIndex(first_claimed_core_index)),
 				)
@@ -791,7 +793,7 @@ pub(crate) fn check_assignment_cert(
 			let (vrf_in_out, _) = public
 				.vrf_verify(
 					relay_vrf_delay_transcript(relay_vrf_story, *core_index),
-					&vrf_output.0,
+					&vrf_pre_output.0,
 					&vrf_proof.0,
 				)
 				.map_err(|_| InvalidAssignment(Reason::VRFDelayOutputMismatch))?;

polkadot/node/core/approval-voting/src/tests.rs

@@ -20,7 +20,7 @@ use crate::backend::V1ReadBackend;
 use polkadot_node_primitives::{
 	approval::{
 		v1::{
-			AssignmentCert, AssignmentCertKind, DelayTranche, VrfOutput, VrfProof, VrfSignature,
+			AssignmentCert, AssignmentCertKind, DelayTranche, VrfPreOutput, VrfProof, VrfSignature,
 			RELAY_VRF_MODULO_CONTEXT,
 		},
 		v2::{AssignmentCertKindV2, AssignmentCertV2},
@@ -415,9 +415,12 @@ fn garbage_assignment_cert(kind: AssignmentCertKind) -> AssignmentCert {
 	let mut prng = rand_core::OsRng;
 	let keypair = schnorrkel::Keypair::generate_with(&mut prng);
 	let (inout, proof, _) = keypair.vrf_sign(ctx.bytes(msg));
-	let out = inout.to_output();
+	let preout = inout.to_output();
 
-	AssignmentCert { kind, vrf: VrfSignature { output: VrfOutput(out), proof: VrfProof(proof) } }
+	AssignmentCert {
+		kind,
+		vrf: VrfSignature { pre_output: VrfPreOutput(preout), proof: VrfProof(proof) },
+	}
 }
 
 fn garbage_assignment_cert_v2(kind: AssignmentCertKindV2) -> AssignmentCertV2 {
@@ -426,9 +429,12 @@ fn garbage_assignment_cert_v2(kind: AssignmentCertKindV2) -> AssignmentCertV2 {
 	let mut prng = rand_core::OsRng;
 	let keypair = schnorrkel::Keypair::generate_with(&mut prng);
 	let (inout, proof, _) = keypair.vrf_sign(ctx.bytes(msg));
-	let out = inout.to_output();
+	let preout = inout.to_output();
 
-	AssignmentCertV2 { kind, vrf: VrfSignature { output: VrfOutput(out), proof: VrfProof(proof) } }
+	AssignmentCertV2 {
+		kind,
+		vrf: VrfSignature { pre_output: VrfPreOutput(preout), proof: VrfProof(proof) },
+	}
 }
 
 fn sign_approval(

polkadot/node/network/approval-distribution/src/tests.rs

@@ -25,7 +25,7 @@ use polkadot_node_network_protocol::{
 };
 use polkadot_node_primitives::approval::{
 	v1::{
-		AssignmentCert, AssignmentCertKind, IndirectAssignmentCert, VrfOutput, VrfProof,
+		AssignmentCert, AssignmentCertKind, IndirectAssignmentCert, VrfPreOutput, VrfProof,
 		VrfSignature,
 	},
 	v2::{
@@ -298,14 +298,14 @@ fn fake_assignment_cert(block_hash: Hash, validator: ValidatorIndex) -> Indirect
 	let mut prng = rand_core::OsRng;
 	let keypair = schnorrkel::Keypair::generate_with(&mut prng);
 	let (inout, proof, _) = keypair.vrf_sign(ctx.bytes(msg));
-	let out = inout.to_output();
+	let preout = inout.to_output();
 
 	IndirectAssignmentCert {
 		block_hash,
 		validator,
 		cert: AssignmentCert {
 			kind: AssignmentCertKind::RelayVRFModulo { sample: 1 },
-			vrf: VrfSignature { output: VrfOutput(out), proof: VrfProof(proof) },
+			vrf: VrfSignature { pre_output: VrfPreOutput(preout), proof: VrfProof(proof) },
 		},
 	}
 }
@@ -320,14 +320,14 @@ fn fake_assignment_cert_v2(
 	let mut prng = rand_core::OsRng;
 	let keypair = schnorrkel::Keypair::generate_with(&mut prng);
 	let (inout, proof, _) = keypair.vrf_sign(ctx.bytes(msg));
-	let out = inout.to_output();
+	let preout = inout.to_output();
 
 	IndirectAssignmentCertV2 {
 		block_hash,
 		validator,
 		cert: AssignmentCertV2 {
 			kind: AssignmentCertKindV2::RelayVRFModuloCompact { core_bitfield },
-			vrf: VrfSignature { output: VrfOutput(out), proof: VrfProof(proof) },
+			vrf: VrfSignature { pre_output: VrfPreOutput(preout), proof: VrfProof(proof) },
 		},
 	}
 }

polkadot/node/primitives/src/approval.rs

@@ -20,7 +20,7 @@
 pub mod v1 {
 	use sp_consensus_babe as babe_primitives;
 	pub use sp_consensus_babe::{
-		Randomness, Slot, VrfOutput, VrfProof, VrfSignature, VrfTranscript,
+		Randomness, Slot, VrfPreOutput, VrfProof, VrfSignature, VrfTranscript,
 	};
 
 	use parity_scale_codec::{Decode, Encode};
@@ -145,14 +145,14 @@ pub mod v1 {
 		AuthorityOutOfBounds(usize),
 	}
 
-	/// An unsafe VRF output. Provide BABE Epoch info to create a `RelayVRFStory`.
-	pub struct UnsafeVRFOutput {
-		vrf_output: VrfOutput,
+	/// An unsafe VRF pre-output. Provide BABE Epoch info to create a `RelayVRFStory`.
+	pub struct UnsafeVRFPreOutput {
+		vrf_pre_output: VrfPreOutput,
 		slot: Slot,
 		authority_index: u32,
 	}
 
-	impl UnsafeVRFOutput {
+	impl UnsafeVRFPreOutput {
 		/// Get the slot.
 		pub fn slot(&self) -> Slot {
 			self.slot
@@ -177,7 +177,7 @@ pub mod v1 {
 				sp_consensus_babe::make_vrf_transcript(randomness, self.slot, epoch_index);
 
 			let inout = self
-				.vrf_output
+				.vrf_pre_output
 				.0
 				.attach_input_hash(&pubkey, transcript.0)
 				.map_err(ApprovalError::SchnorrkelSignature)?;
@@ -190,16 +190,16 @@ pub mod v1 {
 	/// This fails if either there is no BABE `PreRuntime` digest or
 	/// the digest has type `SecondaryPlain`, which Substrate nodes do
 	/// not produce or accept anymore.
-	pub fn babe_unsafe_vrf_info(header: &Header) -> Option<UnsafeVRFOutput> {
+	pub fn babe_unsafe_vrf_info(header: &Header) -> Option<UnsafeVRFPreOutput> {
 		use babe_primitives::digests::CompatibleDigestItem;
 
 		for digest in &header.digest.logs {
 			if let Some(pre) = digest.as_babe_pre_digest() {
 				let slot = pre.slot();
 				let authority_index = pre.authority_index();
 
-				return pre.vrf_signature().map(|sig| UnsafeVRFOutput {
-					vrf_output: sig.output.clone(),
+				return pre.vrf_signature().map(|sig| UnsafeVRFPreOutput {
+					vrf_pre_output: sig.pre_output.clone(),
 					slot,
 					authority_index,
 				})
@@ -214,7 +214,7 @@ pub mod v1 {
 pub mod v2 {
 	use parity_scale_codec::{Decode, Encode};
 	pub use sp_consensus_babe::{
-		Randomness, Slot, VrfOutput, VrfProof, VrfSignature, VrfTranscript,
+		Randomness, Slot, VrfPreOutput, VrfProof, VrfSignature, VrfTranscript,
 	};
 	use std::ops::BitOr;
 

substrate/client/consensus/babe/src/authorship.rs

@@ -249,7 +249,7 @@ fn claim_primary_slot(
 				.make_bytes::<AUTHORING_SCORE_LENGTH>(
 					AUTHORING_SCORE_VRF_CONTEXT,
 					&data.as_ref(),
-					&vrf_signature.output,
+					&vrf_signature.pre_output,
 				)
 				.map(|bytes| u128::from_le_bytes(bytes) < threshold)
 				.unwrap_or_default();

substrate/client/consensus/babe/src/tests.rs

@@ -580,7 +580,7 @@ fn claim_vrf_check() {
 	};
 	let data = make_vrf_sign_data(&epoch.randomness.clone(), 0.into(), epoch.epoch_index);
 	let sign = keystore.sr25519_vrf_sign(AuthorityId::ID, &public, &data).unwrap().unwrap();
-	assert_eq!(pre_digest.vrf_signature.output, sign.output);
+	assert_eq!(pre_digest.vrf_signature.pre_output, sign.pre_output);
 
 	// We expect a SecondaryVRF claim for slot 1
 	let pre_digest = match claim_slot(1.into(), &epoch, &keystore).unwrap().0 {
@@ -589,7 +589,7 @@ fn claim_vrf_check() {
 	};
 	let data = make_vrf_sign_data(&epoch.randomness.clone(), 1.into(), epoch.epoch_index);
 	let sign = keystore.sr25519_vrf_sign(AuthorityId::ID, &public, &data).unwrap().unwrap();
-	assert_eq!(pre_digest.vrf_signature.output, sign.output);
+	assert_eq!(pre_digest.vrf_signature.pre_output, sign.pre_output);
 
 	// Check that correct epoch index has been used if epochs are skipped (primary VRF)
 	let slot = Slot::from(103);
@@ -601,7 +601,7 @@ fn claim_vrf_check() {
 	let data = make_vrf_sign_data(&epoch.randomness.clone(), slot, fixed_epoch.epoch_index);
 	let sign = keystore.sr25519_vrf_sign(AuthorityId::ID, &public, &data).unwrap().unwrap();
 	assert_eq!(fixed_epoch.epoch_index, 11);
-	assert_eq!(claim.vrf_signature.output, sign.output);
+	assert_eq!(claim.vrf_signature.pre_output, sign.pre_output);
 
 	// Check that correct epoch index has been used if epochs are skipped (secondary VRF)
 	let slot = Slot::from(100);
@@ -613,7 +613,7 @@ fn claim_vrf_check() {
 	let data = make_vrf_sign_data(&epoch.randomness.clone(), slot, fixed_epoch.epoch_index);
 	let sign = keystore.sr25519_vrf_sign(AuthorityId::ID, &public, &data).unwrap().unwrap();
 	assert_eq!(fixed_epoch.epoch_index, 11);
-	assert_eq!(pre_digest.vrf_signature.output, sign.output);
+	assert_eq!(pre_digest.vrf_signature.pre_output, sign.pre_output);
 }
 
 // Propose and import a new BABE block on top of the given parent.

substrate/client/consensus/babe/src/verification.rs

@@ -185,7 +185,7 @@ fn check_primary_header<B: BlockT + Sized>(
 		.make_bytes::<AUTHORING_SCORE_LENGTH>(
 			AUTHORING_SCORE_VRF_CONTEXT,
 			&data.as_ref(),
-			&pre_digest.vrf_signature.output,
+			&pre_digest.vrf_signature.pre_output,
 		)
 		.map(u128::from_le_bytes)
 		.map_err(|_| babe_err(Error::VrfVerificationFailed))?;

substrate/client/keystore/src/local.rs

@@ -120,18 +120,18 @@ impl LocalKeystore {
 		Ok(sig)
 	}
 
-	fn vrf_output<T: CorePair + VrfSecret>(
+	fn vrf_pre_output<T: CorePair + VrfSecret>(
 		&self,
 		key_type: KeyTypeId,
 		public: &T::Public,
 		input: &T::VrfInput,
-	) -> std::result::Result<Option<T::VrfOutput>, TraitError> {
-		let preout = self
+	) -> std::result::Result<Option<T::VrfPreOutput>, TraitError> {
+		let pre_output = self
 			.0
 			.read()
 			.key_pair_by_type::<T>(public, key_type)?
-			.map(|pair| pair.vrf_output(input));
-		Ok(preout)
+			.map(|pair| pair.vrf_pre_output(input));
+		Ok(pre_output)
 	}
 }
 
@@ -188,13 +188,13 @@ impl Keystore for LocalKeystore {
 		self.vrf_sign::<sr25519::Pair>(key_type, public, data)
 	}
 
-	fn sr25519_vrf_output(
+	fn sr25519_vrf_pre_output(
 		&self,
 		key_type: KeyTypeId,
 		public: &sr25519::Public,
 		input: &sr25519::vrf::VrfInput,
-	) -> std::result::Result<Option<sr25519::vrf::VrfOutput>, TraitError> {
-		self.vrf_output::<sr25519::Pair>(key_type, public, input)
+	) -> std::result::Result<Option<sr25519::vrf::VrfPreOutput>, TraitError> {
+		self.vrf_pre_output::<sr25519::Pair>(key_type, public, input)
 	}
 
 	fn ed25519_public_keys(&self, key_type: KeyTypeId) -> Vec<ed25519::Public> {
@@ -293,13 +293,13 @@ impl Keystore for LocalKeystore {
 			self.vrf_sign::<bandersnatch::Pair>(key_type, public, data)
 		}
 
-		fn bandersnatch_vrf_output(
+		fn bandersnatch_vrf_pre_output(
 			&self,
 			key_type: KeyTypeId,
 			public: &bandersnatch::Public,
 			input: &bandersnatch::vrf::VrfInput,
-		) -> std::result::Result<Option<bandersnatch::vrf::VrfOutput>, TraitError> {
-			self.vrf_output::<bandersnatch::Pair>(key_type, public, input)
+		) -> std::result::Result<Option<bandersnatch::vrf::VrfPreOutput>, TraitError> {
+			self.vrf_pre_output::<bandersnatch::Pair>(key_type, public, input)
 		}
 
 		fn bandersnatch_ring_vrf_sign(

substrate/frame/babe/src/lib.rs

@@ -384,7 +384,11 @@ pub mod pallet {
 							});
 
 							public
-								.make_bytes(RANDOMNESS_VRF_CONTEXT, &transcript, &signature.output)
+								.make_bytes(
+									RANDOMNESS_VRF_CONTEXT,
+									&transcript,
+									&signature.pre_output,
+								)
 								.ok()
 						});