chore: set empty hash to hash of nothing

core/header/service.go

@@ -33,26 +33,20 @@ func (i *Info) Bytes() ([]byte, error) {
 	binary.LittleEndian.PutUint64(heightBytes, uint64(i.Height))
 	buf = append(buf, heightBytes...)
 
-	// TODO; permit empty hash OK for genesis block?
-	if len(i.Hash) == 0 {
-		i.Hash = make([]byte, hashSize)
-	}
 	// Encode Hash
 	if len(i.Hash) != hashSize {
 		return nil, errors.New("invalid hash size")
 	}
+
 	buf = append(buf, i.Hash...)
 
 	// Encode Time
 	timeBytes := make([]byte, 8)
 	binary.LittleEndian.PutUint64(timeBytes, uint64(i.Time.Unix()))
 	buf = append(buf, timeBytes...)
 
-	if len(i.AppHash) == 0 {
-		i.AppHash = make([]byte, hashSize)
-	}
 	// Encode AppHash
-	if len(i.Hash) != hashSize {
+	if len(i.AppHash) != hashSize {
 		return nil, errors.New("invalid hash size")
 	}
 	buf = append(buf, i.AppHash...)

server/v2/cometbft/abci.go

@@ -2,6 +2,7 @@ package cometbft
 
 import (
 	"context"
+	"crypto/sha256"
 	"errors"
 	"fmt"
 	"sync/atomic"
@@ -103,7 +104,7 @@ func (c *Consensus[T]) CheckTx(ctx context.Context, req *abciproto.CheckTxReques
 		return nil, err
 	}
 
-	cometResp := &abci.CheckTxResponse{
+	cometResp := &abciproto.CheckTxResponse{
 		Code:      resp.Code,
 		GasWanted: uint64ToInt64(resp.GasWanted),
 		GasUsed:   uint64ToInt64(resp.GasUsed),
@@ -137,7 +138,7 @@ func (c *Consensus[T]) Info(ctx context.Context, _ *abciproto.InfoRequest) (*abc
 		return nil, err
 	}
 
-	return &abci.InfoResponse{
+	return &abciproto.InfoResponse{
 		Data:    c.cfg.Name,
 		Version: c.cfg.Version,
 		// AppVersion:       cp.GetVersion().App,
@@ -226,11 +227,19 @@ func (c *Consensus[T]) InitChain(ctx context.Context, req *abciproto.InitChainRe
 		})
 	}
 
+	ci, err := c.store.LastCommitID()
+	if err != nil {
+		return nil, err
+	}
+
+	// populate hash with empty byte slice instead of nil
+	bz := sha256.Sum256([]byte{})
+
 	br := &coreappmgr.BlockRequest[T]{
 		Height:            uint64(req.InitialHeight - 1),
 		Time:              req.Time,
-		Hash:              nil,
-		AppHash:           nil,
+		Hash:              bz[:],
+		AppHash:           ci.Hash,
 		ChainId:           req.ChainId,
 		ConsensusMessages: consMessages,
 		IsGenesis:         true,
@@ -271,7 +280,7 @@ func (c *Consensus[T]) InitChain(ctx context.Context, req *abciproto.InitChainRe
 		return nil, fmt.Errorf("unable to write the changeset: %w", err)
 	}
 
-	return &abci.InitChainResponse{
+	return &abciproto.InitChainResponse{
 		ConsensusParams: req.ConsensusParams,
 		Validators:      validatorUpdates,
 		AppHash:         stateRoot,
@@ -317,7 +326,7 @@ func (c *Consensus[T]) PrepareProposal(
 		encodedTxs[i] = tx.Bytes()
 	}
 
-	return &abci.PrepareProposalResponse{
+	return &abciproto.PrepareProposalResponse{
 		Txs: encodedTxs,
 	}, nil
 }
@@ -350,13 +359,13 @@ func (c *Consensus[T]) ProcessProposal(
 	err := c.processProposalHandler(ciCtx, c.app, decodedTxs, req)
 	if err != nil {
 		c.logger.Error("failed to process proposal", "height", req.Height, "time", req.Time, "hash", fmt.Sprintf("%X", req.Hash), "err", err)
-		return &abci.ProcessProposalResponse{
-			Status: abci.PROCESS_PROPOSAL_STATUS_REJECT,
+		return &abciproto.ProcessProposalResponse{
+			Status: abciproto.PROCESS_PROPOSAL_STATUS_REJECT,
 		}, nil
 	}
 
-	return &abci.ProcessProposalResponse{
-		Status: abci.PROCESS_PROPOSAL_STATUS_ACCEPT,
+	return &abciproto.ProcessProposalResponse{
+		Status: abciproto.PROCESS_PROPOSAL_STATUS_ACCEPT,
 	}, nil
 }
 
@@ -529,7 +538,7 @@ func (c *Consensus[T]) VerifyVoteExtension(
 	resp, err := c.verifyVoteExt(ctx, latestStore, req)
 	if err != nil {
 		c.logger.Error("failed to verify vote extension", "height", req.Height, "err", err)
-		return &abci.VerifyVoteExtensionResponse{Status: abci.VERIFY_VOTE_EXTENSION_STATUS_REJECT}, nil
+		return &abciproto.VerifyVoteExtensionResponse{Status: abciproto.VERIFY_VOTE_EXTENSION_STATUS_REJECT}, nil
 	}
 
 	return resp, err
@@ -565,7 +574,7 @@ func (c *Consensus[T]) ExtendVote(ctx context.Context, req *abciproto.ExtendVote
 	resp, err := c.extendVote(ctx, latestStore, req)
 	if err != nil {
 		c.logger.Error("failed to verify vote extension", "height", req.Height, "err", err)
-		return &abci.ExtendVoteResponse{}, nil
+		return &abciproto.ExtendVoteResponse{}, nil
 	}
 
 	return resp, err

server/v2/stf/core_header_service.go

@@ -4,6 +4,7 @@ import (
 	"context"
 
 	"cosmossdk.io/core/header"
+	"cosmossdk.io/core/store"
 )
 
 var _ header.Service = (*HeaderService)(nil)
@@ -13,3 +14,42 @@ type HeaderService struct{}
 func (h HeaderService) HeaderInfo(ctx context.Context) header.Info {
 	return ctx.(*executionContext).headerInfo
 }
+
+const headerInfoPrefix = 0x37
+
+// setHeaderInfo sets the header info in the state to be used by queries in the future.
+func (s STF[T]) setHeaderInfo(state store.WriterMap, headerInfo header.Info) error {
+	// TODO storing header info is too low level here, stf should be stateless.
+	// We should have a keeper that does this.
+	runtimeStore, err := state.GetWriter(Identity)
+	if err != nil {
+		return err
+	}
+	bz, err := headerInfo.Bytes()
+	if err != nil {
+		return err
+	}
+	err = runtimeStore.Set([]byte{headerInfoPrefix}, bz)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// getHeaderInfo gets the header info from the state. It should only be used for queries
+func (s STF[T]) getHeaderInfo(state store.WriterMap) (i header.Info, err error) {
+	runtimeStore, err := state.GetWriter(Identity)
+	if err != nil {
+		return header.Info{}, err
+	}
+	v, err := runtimeStore.Get([]byte{headerInfoPrefix})
+	if err != nil {
+		return header.Info{}, err
+	}
+	if v == nil {
+		return header.Info{}, nil
+	}
+
+	err = i.FromBytes(v)
+	return i, err
+}

server/v2/stf/stf.go

@@ -421,45 +421,6 @@ func (s STF[T]) validatorUpdates(
 	return ctx.events, valSetUpdates, nil
 }
 
-const headerInfoPrefix = 0x37
-
-// setHeaderInfo sets the header info in the state to be used by queries in the future.
-func (s STF[T]) setHeaderInfo(state store.WriterMap, headerInfo header.Info) error {
-	// TODO storing header info is too low level here, stf should be stateless.
-	// We should have a keeper that does this.
-	runtimeStore, err := state.GetWriter(Identity)
-	if err != nil {
-		return err
-	}
-	bz, err := headerInfo.Bytes()
-	if err != nil {
-		return err
-	}
-	err = runtimeStore.Set([]byte{headerInfoPrefix}, bz)
-	if err != nil {
-		return err
-	}
-	return nil
-}
-
-// getHeaderInfo gets the header info from the state. It should only be used for queries
-func (s STF[T]) getHeaderInfo(state store.WriterMap) (i header.Info, err error) {
-	runtimeStore, err := state.GetWriter(Identity)
-	if err != nil {
-		return header.Info{}, err
-	}
-	v, err := runtimeStore.Get([]byte{headerInfoPrefix})
-	if err != nil {
-		return header.Info{}, err
-	}
-	if v == nil {
-		return header.Info{}, nil
-	}
-
-	err = i.FromBytes(v)
-	return i, err
-}
-
 // Simulate simulates the execution of a tx on the provided state.
 func (s STF[T]) Simulate(
 	ctx context.Context,

store/v2/root/store.go

@@ -2,6 +2,7 @@ package root
 
 import (
 	"bytes"
+	"crypto/sha256"
 	"errors"
 	"fmt"
 	"sync"
@@ -148,8 +149,10 @@ func (s *Store) LastCommitID() (proof.CommitID, error) {
 	if err != nil {
 		return proof.CommitID{}, err
 	}
+	// if the latest version is 0, we return a CommitID with version 0 and a hash of an empty byte slice
+	bz := sha256.Sum256([]byte{})
 
-	return proof.CommitID{Version: latestVersion}, nil
+	return proof.CommitID{Version: latestVersion, Hash: bz[:]}, nil
 }
 
 // GetLatestVersion returns the latest version based on the latest internal