Merge pull request #1425 from filecoin-project/fix/randomness-for-ec

use proper lookback, and proper serialization for randomness generation

build/params_shared.go

@@ -64,7 +64,7 @@ const MaxSealLookback = SealRandomnessLookbackLimit + 2000
 // Mining
 
 // Epochs
-const EcRandomnessLookback = 300
+const EcRandomnessLookback = 1
 
 // /////
 // Devnet settings

chain/gen/gen.go

@@ -276,8 +276,12 @@ func CarWalkFunc(nd format.Node) (out []*format.Link, err error) {
 func (cg *ChainGen) nextBlockProof(ctx context.Context, pts *types.TipSet, m address.Address, round int64) (*types.EPostProof, *types.Ticket, error) {
 	mc := &mca{w: cg.w, sm: cg.sm}
 
-	// TODO: REVIEW: Am I doing this correctly?
+	buf := new(bytes.Buffer)
-	ticketRand, err := mc.ChainGetRandomness(ctx, pts.Key(), crypto.DomainSeparationTag_TicketProduction, pts.Height(), m.Bytes())
+	if err := m.MarshalCBOR(buf); err != nil {
+		return nil, nil, xerrors.Errorf("failed to cbor marshal address: %w", err)
+	}
+
+	ticketRand, err := mc.ChainGetRandomness(ctx, pts.Key(), crypto.DomainSeparationTag_TicketProduction, abi.ChainEpoch(round-build.EcRandomnessLookback), buf.Bytes())
 	if err != nil {
 		return nil, nil, err
 	}
@@ -549,7 +553,11 @@ type ProofInput struct {
 }
 
 func IsRoundWinner(ctx context.Context, ts *types.TipSet, round int64, miner address.Address, epp ElectionPoStProver, a MiningCheckAPI) (*ProofInput, error) {
-	epostRand, err := a.ChainGetRandomness(ctx, ts.Key(), crypto.DomainSeparationTag_ElectionPoStChallengeSeed, abi.ChainEpoch(round-build.EcRandomnessLookback), miner.Bytes())
+	buf := new(bytes.Buffer)
+	if err := miner.MarshalCBOR(buf); err != nil {
+		return nil, xerrors.Errorf("failed to cbor marshal address: %w")
+	}
+	epostRand, err := a.ChainGetRandomness(ctx, ts.Key(), crypto.DomainSeparationTag_ElectionPoStChallengeSeed, abi.ChainEpoch(round-build.EcRandomnessLookback), buf.Bytes())
 	if err != nil {
 		return nil, xerrors.Errorf("chain get randomness: %w", err)
 	}

chain/sync.go

@@ -1,6 +1,7 @@
 package chain
 
 import (
+	"bytes"
 	"context"
 	"errors"
 	"fmt"
@@ -617,7 +618,11 @@ func (syncer *Syncer) ValidateBlock(ctx context.Context, b *types.FullBlock) err
 	})
 
 	tktsCheck := async.Err(func() error {
-		vrfBase, err := syncer.sm.ChainStore().GetRandomness(ctx, baseTs.Cids(), crypto.DomainSeparationTag_TicketProduction, int64(baseTs.Height()), h.Miner.Bytes())
+		buf := new(bytes.Buffer)
+		if err := h.Miner.MarshalCBOR(buf); err != nil {
+			return xerrors.Errorf("failed to marshal miner address to cbor: %w", err)
+		}
+		vrfBase, err := syncer.sm.ChainStore().GetRandomness(ctx, baseTs.Cids(), crypto.DomainSeparationTag_TicketProduction, int64(baseTs.Height()), buf.Bytes())
 		if err != nil {
 			return xerrors.Errorf("failed to get randomness for verifying election proof: %w", err)
 		}
@@ -656,7 +661,11 @@ func (syncer *Syncer) ValidateBlock(ctx context.Context, b *types.FullBlock) err
 }
 
 func (syncer *Syncer) VerifyElectionPoStProof(ctx context.Context, h *types.BlockHeader, baseTs *types.TipSet, waddr address.Address) error {
-	rand, err := syncer.sm.ChainStore().GetRandomness(ctx, baseTs.Cids(), crypto.DomainSeparationTag_ElectionPoStChallengeSeed, int64(h.Height-build.EcRandomnessLookback), h.Miner.Bytes())
+	buf := new(bytes.Buffer)
+	if err := h.Miner.MarshalCBOR(buf); err != nil {
+		return xerrors.Errorf("failed to marshal miner to cbor: %w", err)
+	}
+	rand, err := syncer.sm.ChainStore().GetRandomness(ctx, baseTs.Cids(), crypto.DomainSeparationTag_ElectionPoStChallengeSeed, int64(h.Height-build.EcRandomnessLookback), buf.Bytes())
 	if err != nil {
 		return xerrors.Errorf("failed to get randomness for verifying election proof: %w", err)
 	}

miner/miner.go

@@ -1,12 +1,13 @@
 package miner
 
 import (
+	"bytes"
 	"context"
 	"fmt"
 	"sync"
 	"time"
 
-	"github.com/filecoin-project/go-address"
+	address "github.com/filecoin-project/go-address"
 	"github.com/filecoin-project/specs-actors/actors/abi"
 	"github.com/filecoin-project/specs-actors/actors/crypto"
 	lru "github.com/hashicorp/golang-lru"
@@ -348,7 +349,12 @@ func (m *Miner) computeTicket(ctx context.Context, addr address.Address, base *M
 		return nil, err
 	}
 
-	input, err := m.api.ChainGetRandomness(ctx, base.ts.Key(), crypto.DomainSeparationTag_TicketProduction, base.ts.Height(), addr.Bytes())
+	buf := new(bytes.Buffer)
+	if err := addr.MarshalCBOR(buf); err != nil {
+		return nil, xerrors.Errorf("failed to marshal address to cbor: %w", err)
+	}
+
+	input, err := m.api.ChainGetRandomness(ctx, base.ts.Key(), crypto.DomainSeparationTag_TicketProduction, base.ts.Height(), buf.Bytes())
 	if err != nil {
 		return nil, err
 	}