prysm-pulse/shared/testutil/helpers.go
2021-05-26 11:33:46 -07:00

80 lines
2.7 KiB
Go

package testutil
import (
"context"
"encoding/binary"
"testing"
"github.com/pkg/errors"
types "github.com/prysmaticlabs/eth2-types"
ethpb "github.com/prysmaticlabs/ethereumapis/eth/v1alpha1"
"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
"github.com/prysmaticlabs/prysm/beacon-chain/core/state"
iface "github.com/prysmaticlabs/prysm/beacon-chain/state/interface"
"github.com/prysmaticlabs/prysm/shared/bls"
"github.com/prysmaticlabs/prysm/shared/interfaces"
"github.com/prysmaticlabs/prysm/shared/params"
"github.com/prysmaticlabs/prysm/shared/rand"
)
// RandaoReveal returns a signature of the requested epoch using the beacon proposer private key.
func RandaoReveal(beaconState iface.ReadOnlyBeaconState, epoch types.Epoch, privKeys []bls.SecretKey) ([]byte, error) {
// We fetch the proposer's index as that is whom the RANDAO will be verified against.
proposerIdx, err := helpers.BeaconProposerIndex(beaconState)
if err != nil {
return []byte{}, errors.Wrap(err, "could not get beacon proposer index")
}
buf := make([]byte, 32)
binary.LittleEndian.PutUint64(buf, uint64(epoch))
// We make the previous validator's index sign the message instead of the proposer.
sszEpoch := types.SSZUint64(epoch)
return helpers.ComputeDomainAndSign(beaconState, epoch, &sszEpoch, params.BeaconConfig().DomainRandao, privKeys[proposerIdx])
}
// BlockSignature calculates the post-state root of the block and returns the signature.
func BlockSignature(
bState iface.BeaconState,
block *ethpb.BeaconBlock,
privKeys []bls.SecretKey,
) (bls.Signature, error) {
var err error
s, err := state.CalculateStateRoot(context.Background(), bState, interfaces.WrappedPhase0SignedBeaconBlock(&ethpb.SignedBeaconBlock{Block: block}))
if err != nil {
return nil, err
}
block.StateRoot = s[:]
domain, err := helpers.Domain(bState.Fork(), helpers.CurrentEpoch(bState), params.BeaconConfig().DomainBeaconProposer, bState.GenesisValidatorRoot())
if err != nil {
return nil, err
}
blockRoot, err := helpers.ComputeSigningRoot(block, domain)
if err != nil {
return nil, err
}
// Temporarily increasing the beacon state slot here since BeaconProposerIndex is a
// function deterministic on beacon state slot.
currentSlot := bState.Slot()
if err := bState.SetSlot(block.Slot); err != nil {
return nil, err
}
proposerIdx, err := helpers.BeaconProposerIndex(bState)
if err != nil {
return nil, err
}
if err := bState.SetSlot(currentSlot); err != nil {
return nil, err
}
return privKeys[proposerIdx].Sign(blockRoot[:]), nil
}
// Random32Bytes generates a random 32 byte slice.
func Random32Bytes(t *testing.T) []byte {
b := make([]byte, 32)
_, err := rand.NewDeterministicGenerator().Read(b)
if err != nil {
t.Fatal(err)
}
return b
}