Modify BeaconState and BeaconBlockBody to reflect changes in the specs. Also add new variable LATEST_RANDAO_MIXES_LENGTH to foundation

Signed-off-by: Kirk Baird <kirk@sigmaprime.io>

beacon_chain/genesis/src/beacon_block.rs

@@ -16,6 +16,9 @@ pub fn genesis_beacon_block(state_root: Hash256, spec: &ChainSpec) -> BeaconBloc
             proposer_slashings: vec![],
             casper_slashings: vec![],
             attestations: vec![],
+            custody_reseeds: vec![],
+            custody_challenges: vec![],
+            custody_responses: vec![],
             deposits: vec![],
             exits: vec![],
         },

beacon_chain/genesis/src/beacon_state.rs

@@ -47,11 +47,13 @@ pub fn genesis_beacon_state(spec: &ChainSpec) -> Result<BeaconState, Error> {
         /*
          * Randomness and committees
          */
-        randao_mix: spec.zero_hash,
+        latest_randao_mixes: vec![spec.zero_hash; spec.latest_randao_mixes_length as usize],
-        next_seed: spec.zero_hash,
+        latest_vdf_outputs: vec![spec.zero_hash; (spec.latest_randao_mixes_length / spec.epoch_length) as usize],
         shard_committees_at_slots: vec![],
-        persistent_committees: vec![],
+        /*
-        persistent_committee_reassignments: vec![],
+         * Custody challenges
+         */
+        custody_challenges: vec![],
         /*
          * Finality
          */
@@ -66,6 +68,7 @@ pub fn genesis_beacon_state(spec: &ChainSpec) -> Result<BeaconState, Error> {
         latest_block_roots: vec![spec.zero_hash; spec.epoch_length as usize],
         latest_penalized_exit_balances: vec![],
         latest_attestations: vec![],
+        batched_block_roots: vec![],
         /*
          * PoW receipt root
          */

beacon_chain/spec/src/foundation.rs

@@ -24,6 +24,7 @@ impl ChainSpec {
             beacon_chain_shard_number: u64::max_value(),
             bls_withdrawal_prefix_byte: 0x00,
             max_casper_votes: 1_024,
+            latest_randao_mixes_length: 8_192,
             /*
              *  Deposit contract
              */

beacon_chain/spec/src/lib.rs

@@ -18,6 +18,7 @@ pub struct ChainSpec {
     pub beacon_chain_shard_number: u64,
     pub bls_withdrawal_prefix_byte: u8,
     pub max_casper_votes: u64,
+    pub latest_randao_mixes_length: u64,
     /*
      *  Deposit contract
      */

beacon_chain/types/src/beacon_block_body.rs

@@ -3,11 +3,20 @@ use super::{Attestation, CasperSlashing, Deposit, Exit, ProposerSlashing};
 use crate::test_utils::TestRandom;
 use rand::RngCore;
 
+// The following types are just dummy classes as they will not be defined until 
+// Phase 1 (Sharding phase)
+type CustodyReseed = usize;
+type CustodyChallenge = usize;
+type CustodyResponse = usize;
+
 #[derive(Debug, PartialEq, Clone, Default)]
 pub struct BeaconBlockBody {
     pub proposer_slashings: Vec<ProposerSlashing>,
     pub casper_slashings: Vec<CasperSlashing>,
     pub attestations: Vec<Attestation>,
+    pub custody_reseeds: Vec<CustodyReseed>,
+    pub custody_challenges: Vec<CustodyChallenge>,
+    pub custody_responses: Vec<CustodyResponse>,
     pub deposits: Vec<Deposit>,
     pub exits: Vec<Exit>,
 }
@@ -17,6 +26,9 @@ impl Encodable for BeaconBlockBody {
         s.append_vec(&self.proposer_slashings);
         s.append_vec(&self.casper_slashings);
         s.append_vec(&self.attestations);
+        s.append_vec(&self.custody_reseeds);
+        s.append_vec(&self.custody_challenges);
+        s.append_vec(&self.custody_responses);
         s.append_vec(&self.deposits);
         s.append_vec(&self.exits);
     }
@@ -27,6 +39,9 @@ impl Decodable for BeaconBlockBody {
         let (proposer_slashings, i) = <_>::ssz_decode(bytes, i)?;
         let (casper_slashings, i) = <_>::ssz_decode(bytes, i)?;
         let (attestations, i) = <_>::ssz_decode(bytes, i)?;
+        let (custody_reseeds, i) = <_>::ssz_decode(bytes, i)?;
+        let (custody_challenges, i) = <_>::ssz_decode(bytes, i)?;
+        let (custody_responses, i) = <_>::ssz_decode(bytes, i)?;
         let (deposits, i) = <_>::ssz_decode(bytes, i)?;
         let (exits, i) = <_>::ssz_decode(bytes, i)?;
 
@@ -35,6 +50,9 @@ impl Decodable for BeaconBlockBody {
                 proposer_slashings,
                 casper_slashings,
                 attestations,
+                custody_reseeds,
+                custody_challenges,
+                custody_responses,
                 deposits,
                 exits,
             },
@@ -49,6 +67,9 @@ impl<T: RngCore> TestRandom<T> for BeaconBlockBody {
             proposer_slashings: <_>::random_for_test(rng),
             casper_slashings: <_>::random_for_test(rng),
             attestations: <_>::random_for_test(rng),
+            custody_reseeds: <_>::random_for_test(rng),
+            custody_challenges: <_>::random_for_test(rng),
+            custody_responses: <_>::random_for_test(rng),
             deposits: <_>::random_for_test(rng),
             exits: <_>::random_for_test(rng),
         }

beacon_chain/types/src/beacon_state.rs

@@ -3,7 +3,6 @@ use super::crosslink_record::CrosslinkRecord;
 use super::fork_data::ForkData;
 use super::pending_attestation_record::PendingAttestationRecord;
 use super::shard_committee::ShardCommittee;
-use super::shard_reassignment_record::ShardReassignmentRecord;
 use super::validator_record::ValidatorRecord;
 use super::Hash256;
 use crate::test_utils::TestRandom;
@@ -11,6 +10,9 @@ use hashing::canonical_hash;
 use rand::RngCore;
 use ssz::{ssz_encode, Decodable, DecodeError, Encodable, SszStream};
 
+// Custody will not be added to the specs until Phase 1 (Sharding Phase) so dummay class used.
+type CustodyChallenge = usize;
+
 #[derive(Debug, PartialEq, Clone, Default)]
 pub struct BeaconState {
     // Misc
@@ -26,11 +28,12 @@ pub struct BeaconState {
     pub validator_registry_delta_chain_tip: Hash256,
 
     // Randomness and committees
-    pub randao_mix: Hash256,
+    pub latest_randao_mixes: Vec<Hash256>,
-    pub next_seed: Hash256,
+    pub latest_vdf_outputs: Vec<Hash256>,
     pub shard_committees_at_slots: Vec<Vec<ShardCommittee>>,
-    pub persistent_committees: Vec<Vec<u32>>,
+
-    pub persistent_committee_reassignments: Vec<ShardReassignmentRecord>,
+    // Custody challenges
+    pub custody_challenges: Vec<CustodyChallenge>,
 
     // Finality
     pub previous_justified_slot: u64,
@@ -43,8 +46,9 @@ pub struct BeaconState {
     pub latest_block_roots: Vec<Hash256>,
     pub latest_penalized_exit_balances: Vec<u64>,
     pub latest_attestations: Vec<PendingAttestationRecord>,
+    pub batched_block_roots: Vec<Hash256>,
 
-    // PoW receipt root
+    // PoW receipt root (a.k.a. deposit root)
     pub processed_pow_receipt_root: Hash256,
     pub candidate_pow_receipt_roots: Vec<CandidatePoWReceiptRootRecord>,
 }
@@ -67,11 +71,10 @@ impl Encodable for BeaconState {
         s.append(&self.validator_registry_latest_change_slot);
         s.append(&self.validator_registry_exit_count);
         s.append(&self.validator_registry_delta_chain_tip);
-        s.append(&self.randao_mix);
+        s.append(&self.latest_randao_mixes);
-        s.append(&self.next_seed);
+        s.append(&self.latest_vdf_outputs);
         s.append(&self.shard_committees_at_slots);
-        s.append(&self.persistent_committees);
+        s.append(&self.custody_challenges);
-        s.append(&self.persistent_committee_reassignments);
         s.append(&self.previous_justified_slot);
         s.append(&self.justified_slot);
         s.append(&self.justification_bitfield);
@@ -80,6 +83,7 @@ impl Encodable for BeaconState {
         s.append(&self.latest_block_roots);
         s.append(&self.latest_penalized_exit_balances);
         s.append(&self.latest_attestations);
+        s.append(&self.batched_block_roots);
         s.append(&self.processed_pow_receipt_root);
         s.append(&self.candidate_pow_receipt_roots);
     }
@@ -95,11 +99,10 @@ impl Decodable for BeaconState {
         let (validator_registry_latest_change_slot, i) = <_>::ssz_decode(bytes, i)?;
         let (validator_registry_exit_count, i) = <_>::ssz_decode(bytes, i)?;
         let (validator_registry_delta_chain_tip, i) = <_>::ssz_decode(bytes, i)?;
-        let (randao_mix, i) = <_>::ssz_decode(bytes, i)?;
+        let (latest_randao_mixes, i) = <_>::ssz_decode(bytes, i)?;
-        let (next_seed, i) = <_>::ssz_decode(bytes, i)?;
+        let (latest_vdf_outputs, i) = <_>::ssz_decode(bytes, i)?;
         let (shard_committees_at_slots, i) = <_>::ssz_decode(bytes, i)?;
-        let (persistent_committees, i) = <_>::ssz_decode(bytes, i)?;
+        let (custody_challenges, i) = <_>::ssz_decode(bytes, i)?;
-        let (persistent_committee_reassignments, i) = <_>::ssz_decode(bytes, i)?;
         let (previous_justified_slot, i) = <_>::ssz_decode(bytes, i)?;
         let (justified_slot, i) = <_>::ssz_decode(bytes, i)?;
         let (justification_bitfield, i) = <_>::ssz_decode(bytes, i)?;
@@ -108,6 +111,7 @@ impl Decodable for BeaconState {
         let (latest_block_roots, i) = <_>::ssz_decode(bytes, i)?;
         let (latest_penalized_exit_balances, i) = <_>::ssz_decode(bytes, i)?;
         let (latest_attestations, i) = <_>::ssz_decode(bytes, i)?;
+        let (batched_block_roots, i) = <_>::ssz_decode(bytes, i)?;
         let (processed_pow_receipt_root, i) = <_>::ssz_decode(bytes, i)?;
         let (candidate_pow_receipt_roots, i) = <_>::ssz_decode(bytes, i)?;
 
@@ -121,11 +125,10 @@ impl Decodable for BeaconState {
                 validator_registry_latest_change_slot,
                 validator_registry_exit_count,
                 validator_registry_delta_chain_tip,
-                randao_mix,
+                latest_randao_mixes,
-                next_seed,
+                latest_vdf_outputs,
                 shard_committees_at_slots,
-                persistent_committees,
+                custody_challenges,
-                persistent_committee_reassignments,
                 previous_justified_slot,
                 justified_slot,
                 justification_bitfield,
@@ -134,6 +137,7 @@ impl Decodable for BeaconState {
                 latest_block_roots,
                 latest_penalized_exit_balances,
                 latest_attestations,
+                batched_block_roots,
                 processed_pow_receipt_root,
                 candidate_pow_receipt_roots,
             },
@@ -153,11 +157,10 @@ impl<T: RngCore> TestRandom<T> for BeaconState {
             validator_registry_latest_change_slot: <_>::random_for_test(rng),
             validator_registry_exit_count: <_>::random_for_test(rng),
             validator_registry_delta_chain_tip: <_>::random_for_test(rng),
-            randao_mix: <_>::random_for_test(rng),
+            latest_randao_mixes: <_>::random_for_test(rng),
-            next_seed: <_>::random_for_test(rng),
+            latest_vdf_outputs: <_>::random_for_test(rng),
             shard_committees_at_slots: <_>::random_for_test(rng),
-            persistent_committees: <_>::random_for_test(rng),
+            custody_challenges: <_>::random_for_test(rng),
-            persistent_committee_reassignments: <_>::random_for_test(rng),
             previous_justified_slot: <_>::random_for_test(rng),
             justified_slot: <_>::random_for_test(rng),
             justification_bitfield: <_>::random_for_test(rng),
@@ -166,6 +169,7 @@ impl<T: RngCore> TestRandom<T> for BeaconState {
             latest_block_roots: <_>::random_for_test(rng),
             latest_penalized_exit_balances: <_>::random_for_test(rng),
             latest_attestations: <_>::random_for_test(rng),
+            batched_block_roots: <_>::random_for_test(rng),
             processed_pow_receipt_root: <_>::random_for_test(rng),
             candidate_pow_receipt_roots: <_>::random_for_test(rng),
         }