32 lines
895 B
Go
32 lines
895 B
Go
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package consensus
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import (
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"encoding/binary"
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"github.com/Secured-Finance/dione/types"
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"github.com/filecoin-project/go-state-types/crypto"
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"github.com/minio/blake2b-simd"
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"golang.org/x/xerrors"
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)
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func DrawRandomness(rbase []byte, pers crypto.DomainSeparationTag, round types.TaskEpoch, entropy []byte) ([]byte, error) {
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h := blake2b.New256()
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if err := binary.Write(h, binary.BigEndian, int64(pers)); err != nil {
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return nil, xerrors.Errorf("deriving randomness: %w", err)
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}
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VRFDigest := blake2b.Sum256(rbase)
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_, err := h.Write(VRFDigest[:])
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if err != nil {
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return nil, xerrors.Errorf("hashing VRFDigest: %w", err)
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}
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if err := binary.Write(h, binary.BigEndian, round); err != nil {
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return nil, xerrors.Errorf("deriving randomness: %w", err)
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}
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_, err = h.Write(entropy)
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if err != nil {
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return nil, xerrors.Errorf("hashing entropy: %w", err)
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}
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return h.Sum(nil), nil
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}
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