beacon: move beacon-chain to geth-sharding repo (#250)

Former-commit-id: 689de6935d724226eb9125d597831d7b274d79c1 [formerly 4e0c0d671c4e6284cd33300231cc0f7aba99d314]
Former-commit-id: c3079b352bc938c12708b81cdc0130909456ea27

beacon-chain/types/block.go

@@ -0,0 +1,24 @@
+package types
+
+import "github.com/ethereum/go-ethereum/common"
+
+// Header contains the block header fields in beacon chain.
+type Header struct {
+	ParentHash              common.Hash     // ParentHash is the hash of the parent beacon block.
+	SkipCount               uint64          // SkipCount is the number of skips, this is used for the full PoS mechanism.
+	RandaoReveal            common.Hash     // RandaoReveal is used for Randao commitment reveal.
+	AttestationBitmask      []byte          // AttestationBitmask is the bit field of who from the attestation committee participated.
+	AttestationAggregateSig []uint          // AttestationAggregateSig is validator's aggregate sig.
+	ShardAggregateVotes     []AggregateVote // ShardAggregateVotes is shard aggregate votes.
+	MainChainRef            common.Hash     // MainChainRef is the reference to main chain block.
+	StateHash               []byte          // StateHash is the concatenation of crystallized and active state.
+	Sig                     []uint          // Sig is the signature of the proposer.
+}
+
+// AggregateVote contains the fields of aggregate vote in individual shard.
+type AggregateVote struct {
+	ShardID        uint16      // Shard ID of the voted shard.
+	ShardBlockHash common.Hash // ShardBlockHash is the shard block hash of the voted shard.
+	SignerBitmask  []byte      // SignerBitmask is the bit mask of every validator that signed.
+	AggregateSig   []uint      // AggregateSig is the aggregated signatures of individual shard.
+}