attestations

Documentation

Overview

Package attestations tracks the life-cycle of the latest attestations from each validator. It also contains libraries to create attestation message, verify attestation correctness and slashing conditions.

Index

• func IsDoubleVote(attestation1 *pb.AttestationData, attestation2 *pb.AttestationData) bool
• func IsSurroundVote(attestation1 *pb.AttestationData, attestation2 *pb.AttestationData) bool
• func Key(att *pb.AttestationData) [32]byte

Functions

func IsDoubleVote

func IsDoubleVote(attestation1 *pb.AttestationData, attestation2 *pb.AttestationData) bool

IsDoubleVote checks if both of the attestations have been used to vote for the same slot. Spec:

	def is_double_vote(attestation_data_1: AttestationData,
                  attestation_data_2: AttestationData) -> bool
   """
   Checks if the two ``AttestationData`` have the same target.
   """
   target_epoch_1 = slot_to_epoch(attestation_data_1.slot)
   target_epoch_2 = slot_to_epoch(attestation_data_2.slot)
   return target_epoch_1 == target_epoch_2

func IsSurroundVote

func IsSurroundVote(attestation1 *pb.AttestationData, attestation2 *pb.AttestationData) bool

IsSurroundVote checks if the data provided by the attestations fulfill the conditions for a surround vote. Spec:

	def is_surround_vote(attestation_data_1: AttestationData,
                    attestation_data_2: AttestationData) -> bool:
   """
   Checks if ``attestation_data_1`` surrounds ``attestation_data_2``.
   """
   source_epoch_1 = attestation_data_1.justified_epoch
   source_epoch_2 = attestation_data_2.justified_epoch
   target_epoch_1 = slot_to_epoch(attestation_data_1.slot)
   target_epoch_2 = slot_to_epoch(attestation_data_2.slot)

   return source_epoch_1 < source_epoch_2 and target_epoch_2 < target_epoch_1

func Key

func Key(att *pb.AttestationData) [32]byte

Key generates the blake2b hash of the following attestation fields: slotNumber + shardID + blockHash + obliqueParentHash This is used for attestation table look up in localDB.