From 73d928751d7d2344f57c4ff3c5496fd2c2198d10 Mon Sep 17 00:00:00 2001 From: Jeromy Date: Fri, 5 Jun 2020 15:12:13 -0700 Subject: [PATCH] disallow sourcing randomness from future epochs --- chain/store/store.go | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/chain/store/store.go b/chain/store/store.go index 72c77ee36..998129d41 100644 --- a/chain/store/store.go +++ b/chain/store/store.go @@ -904,7 +904,7 @@ func DrawRandomness(rbase []byte, pers crypto.DomainSeparationTag, round abi.Cha return h.Sum(nil), nil } -func (cs *ChainStore) GetRandomness(ctx context.Context, blks []cid.Cid, pers crypto.DomainSeparationTag, round abi.ChainEpoch, entropy []byte) (out []byte, err error) { +func (cs *ChainStore) GetRandomness(ctx context.Context, blks []cid.Cid, pers crypto.DomainSeparationTag, round abi.ChainEpoch, entropy []byte) ([]byte, error) { _, span := trace.StartSpan(ctx, "store.GetRandomness") defer span.End() span.AddAttributes(trace.Int64Attribute("round", int64(round))) @@ -915,7 +915,7 @@ func (cs *ChainStore) GetRandomness(ctx context.Context, blks []cid.Cid, pers cr } if round > ts.Height() { - return DrawRandomness(ts.MinTicket().VRFProof, pers, round, entropy) + return nil, xerrors.Errorf("cannot draw randomness from the future") } searchHeight := round