fix(proposer): verify attestations without mutating state (#12704)

Co-authored-by: Raul Jordan <[email protected]>
Co-authored-by: james-prysm <[email protected]>
Co-authored-by: prylabs-bulldozer[bot] <58059840+prylabs-bulldozer[bot]@users.noreply.github.com>

beacon-chain/rpc/prysm/v1alpha1/validator/proposer_attestations.go

@@ -6,7 +6,6 @@ import (
 
 	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/go-bitfield"
-	"github.com/prysmaticlabs/prysm/v4/beacon-chain/core/altair"
 	"github.com/prysmaticlabs/prysm/v4/beacon-chain/core/blocks"
 	"github.com/prysmaticlabs/prysm/v4/beacon-chain/core/helpers"
 	"github.com/prysmaticlabs/prysm/v4/beacon-chain/state"
@@ -15,7 +14,6 @@ import (
 	ethpb "github.com/prysmaticlabs/prysm/v4/proto/prysm/v1alpha1"
 	"github.com/prysmaticlabs/prysm/v4/proto/prysm/v1alpha1/attestation/aggregation"
 	attaggregation "github.com/prysmaticlabs/prysm/v4/proto/prysm/v1alpha1/attestation/aggregation/attestations"
-	"github.com/prysmaticlabs/prysm/v4/runtime/version"
 	"go.opencensus.io/trace"
 )
 
@@ -83,26 +81,9 @@ func (vs *Server) packAttestations(ctx context.Context, latestState state.Beacon
 func (a proposerAtts) filter(ctx context.Context, st state.BeaconState) (proposerAtts, proposerAtts) {
 	validAtts := make([]*ethpb.Attestation, 0, len(a))
 	invalidAtts := make([]*ethpb.Attestation, 0, len(a))
-	var attestationProcessor func(context.Context, state.BeaconState, *ethpb.Attestation) (state.BeaconState, error)
-
-	if st.Version() == version.Phase0 {
-		attestationProcessor = blocks.ProcessAttestationNoVerifySignature
-	} else if st.Version() >= version.Altair {
-		// Use a wrapper here, as go needs strong typing for the function signature.
-		attestationProcessor = func(ctx context.Context, st state.BeaconState, attestation *ethpb.Attestation) (state.BeaconState, error) {
-			totalBalance, err := helpers.TotalActiveBalance(st)
-			if err != nil {
-				return nil, err
-			}
-			return altair.ProcessAttestationNoVerifySignature(ctx, st, attestation, totalBalance)
-		}
-	} else {
-		// Exit early if there is an unknown state type.
-		return validAtts, invalidAtts
-	}
 
 	for _, att := range a {
-		if _, err := attestationProcessor(ctx, st, att); err == nil {
+		if err := blocks.VerifyAttestationNoVerifySignature(ctx, st, att); err == nil {
 			validAtts = append(validAtts, att)
 			continue
 		}