256-bit custody atoms for better alignment with rest of the spec and greater efficiency

.gitignore

@@ -28,3 +28,13 @@ tests/core/pyspec/test-reports
 tests/core/pyspec/eth2spec/test_results.xml
 
 *.egg-info
+
+# flake8 config
+tox.ini
+
+# VS code files
+.vscode
+*.code-workspace
+
+# npm (for doctoc)
+package-lock.json

Makefile

@@ -71,7 +71,7 @@ pyspec:
 
 # installs the packages to run pyspec tests
 install_test:
-	python3 -m venv venv; . venv/bin/activate; pip3 install .[test] .[lint]
+	python3.8 -m venv venv; . venv/bin/activate; pip3 install .[lint]; pip3 install -e .[test]
 
 test: pyspec
 	. venv/bin/activate; cd $(PY_SPEC_DIR); \
@@ -101,7 +101,7 @@ codespell:
 
 lint: pyspec
 	. venv/bin/activate; cd $(PY_SPEC_DIR); \
-	flake8  --ignore=E252,W504,W503 --max-line-length=120 ./eth2spec \
+	flake8  --ignore=E252,W504,W503,E128,C901 --max-line-length=120 ./eth2spec \
 	&& cd ./eth2spec && mypy --follow-imports=silent --warn-unused-ignores --ignore-missing-imports --check-untyped-defs --disallow-incomplete-defs --disallow-untyped-defs -p phase0 \
 	&& mypy --follow-imports=silent --warn-unused-ignores --ignore-missing-imports --check-untyped-defs --disallow-incomplete-defs --disallow-untyped-defs -p phase1;
 

configs/mainnet/phase1.yaml

@@ -28,6 +28,10 @@ TARGET_SHARD_BLOCK_SIZE: 262144
 SHARD_BLOCK_OFFSETS: [1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233]
 # len(SHARD_BLOCK_OFFSETS)
 MAX_SHARD_BLOCKS_PER_ATTESTATION: 12
+# 2**12 (= 4,096)
+BYTES_PER_CUSTODY_CHUNK: 4096
+# ceillog2(MAX_SHARD_BLOCK_SIZE // BYTES_PER_CUSTODY_CHUNK)
+CUSTODY_RESPONSE_DEPTH: 8
 
 # Gwei values
 # 2**14 (= 16,384) Gwei
@@ -41,10 +45,15 @@ ONLINE_PERIOD: 8
 # 2**8 (= 256) | epochs
 LIGHT_CLIENT_COMMITTEE_PERIOD: 256
 
+# Max operations per block
+# 2**20 (= 1,048,576) 
+MAX_CUSTODY_CHUNK_CHALLENGE_RECORDS: 1048576
+
 # Domain types
 DOMAIN_SHARD_PROPOSAL: 0x80000000
 DOMAIN_SHARD_COMMITTEE: 0x81000000
 DOMAIN_LIGHT_CLIENT: 0x82000000
+# custody-game spec
 DOMAIN_CUSTODY_BIT_SLASHING: 0x83000000
 
 
@@ -53,19 +62,37 @@ DOMAIN_CUSTODY_BIT_SLASHING: 0x83000000
 # Time parameters
 # 2**1 (= 2) epochs, 12.8 minutes
 RANDAO_PENALTY_EPOCHS: 2
+# 2**15 (= 32,768) epochs, ~146 days
+EARLY_DERIVED_SECRET_PENALTY_MAX_FUTURE_EPOCHS: 32768
 # 2**14 (= 16,384) epochs ~73 days
-EARLY_DERIVED_SECRET_PENALTY_MAX_FUTURE_EPOCHS: 16384
-# 2**11 (= 2,048) epochs, ~9 days
-EPOCHS_PER_CUSTODY_PERIOD: 2048
+EPOCHS_PER_CUSTODY_PERIOD: 16384
 # 2**11 (= 2,048) epochs, ~9 days
 CUSTODY_PERIOD_TO_RANDAO_PADDING: 2048
-# 2**7 (= 128) epochs, ~14 hours
-MAX_REVEAL_LATENESS_DECREMENT: 128
+# 2**14 (= 16,384) epochs
+CUSTODY_RESPONSE_DEADLINE: 16384
+# 2**15 (= 32,768) epochs, ~146 days
+MAX_CHUNK_CHALLENGE_DELAY: 32768
+
+# Misc parameters
+# 2**256 - 189
+CUSTODY_PRIME: 115792089237316195423570985008687907853269984665640564039457584007913129639747
+# 3
+CUSTODY_SECRETS: 3
+# 2**5 (= 32) bytes
+BYTES_PER_CUSTODY_ATOM: 32
+# 1/1024 chance of custody bit 1
+CUSTODY_PROBABILITY_EXPONENT: 10
 
 # Max operations
 # 2**8 (= 256)
 MAX_CUSTODY_KEY_REVEALS: 256
+# 2**0 (= 1)
 MAX_EARLY_DERIVED_SECRET_REVEALS: 1
+# 2**2 (= 2)
+MAX_CUSTODY_CHUNK_CHALLENGES: 4
+# 2** 4 (= 16)
+MAX_CUSTODY_CHUNK_CHALLENGE_RESP: 16
+# 2**0 (= 1)
 MAX_CUSTODY_SLASHINGS: 1
 
 # Reward and penalty quotients

configs/minimal/phase1.yaml

@@ -30,6 +30,10 @@ TARGET_SHARD_BLOCK_SIZE: 262144
 SHARD_BLOCK_OFFSETS: [1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233]
 # len(SHARD_BLOCK_OFFSETS)
 MAX_SHARD_BLOCKS_PER_ATTESTATION: 12
+# 2**12 (= 4,096)
+BYTES_PER_CUSTODY_CHUNK: 4096
+# ceillog2(MAX_SHARD_BLOCK_SIZE // BYTES_PER_CUSTODY_CHUNK)
+CUSTODY_RESPONSE_DEPTH: 8
 
 # Gwei values
 # 2**14 (= 16,384) Gwei
@@ -43,10 +47,15 @@ ONLINE_PERIOD: 8
 # 2**8 (= 256) | epochs
 LIGHT_CLIENT_COMMITTEE_PERIOD: 256
 
+# Max operations per block
+# 2**20 (= 1,048,576) 
+MAX_CUSTODY_CHUNK_CHALLENGE_RECORDS: 1048576
+
 # Domain types
 DOMAIN_SHARD_PROPOSAL: 0x80000000
 DOMAIN_SHARD_COMMITTEE: 0x81000000
 DOMAIN_LIGHT_CLIENT: 0x82000000
+# custody-game spec
 DOMAIN_CUSTODY_BIT_SLASHING: 0x83000000
 
 
@@ -56,18 +65,38 @@ DOMAIN_CUSTODY_BIT_SLASHING: 0x83000000
 # 2**1 (= 2) epochs
 RANDAO_PENALTY_EPOCHS: 2
 # [customized] quicker for testing
-EARLY_DERIVED_SECRET_PENALTY_MAX_FUTURE_EPOCHS: 4096
-# 2**11 (= 2,048) epochs
-EPOCHS_PER_CUSTODY_PERIOD: 2048
-# 2**11 (= 2,048) epochs
-CUSTODY_PERIOD_TO_RANDAO_PADDING: 2048
-# 2**7 (= 128) epochs
-MAX_REVEAL_LATENESS_DECREMENT: 128
+EARLY_DERIVED_SECRET_PENALTY_MAX_FUTURE_EPOCHS: 128
+# [customized] quicker for testing
+EPOCHS_PER_CUSTODY_PERIOD: 64
+# [customized] quicker for testing
+CUSTODY_PERIOD_TO_RANDAO_PADDING: 8
+# [customized] quicker for testing
+CUSTODY_RESPONSE_DEADLINE: 128
+# [customize for faster testing]
+MAX_CHUNK_CHALLENGE_DELAY: 128
+
+
+# Misc parameters
+# 2**256 - 189
+CUSTODY_PRIME: 115792089237316195423570985008687907853269984665640564039457584007913129639747
+# 3
+CUSTODY_SECRETS: 3
+# 2**5 (= 32) bytes
+BYTES_PER_CUSTODY_ATOM: 32
+# 1/4 chance of custody bit 1 [customized for faster testing]
+CUSTODY_PROBABILITY_EXPONENT: 2
+
 
 # Max operations
 # 2**8 (= 256)
 MAX_CUSTODY_KEY_REVEALS: 256
+# 2**0 (= 1)
 MAX_EARLY_DERIVED_SECRET_REVEALS: 1
+# [customized]
+MAX_CUSTODY_CHUNK_CHALLENGES: 2
+# [customized]
+MAX_CUSTODY_CHUNK_CHALLENGE_RESP: 8
+# 2**0 (= 1)
 MAX_CUSTODY_SLASHINGS: 1
 
 # Reward and penalty quotients

setup.py

@@ -121,7 +121,7 @@ def get_spec(file_name: str) -> SpecObject:
 from eth2spec.utils.ssz.ssz_impl import hash_tree_root
 from eth2spec.utils.ssz.ssz_typing import (
     View, boolean, Container, List, Vector, uint64, uint8, bit,
-    ByteList, Bytes1, Bytes4, Bytes32, Bytes48, Bytes96, Bitlist, Bitvector,
+    ByteList, ByteVector, Bytes1, Bytes4, Bytes32, Bytes48, Bytes96, Bitlist, Bitvector,
 )
 from eth2spec.utils import bls
 

specs/phase0/beacon-chain.md

@@ -1748,6 +1748,22 @@ def process_attestation(state: BeaconState, attestation: Attestation) -> None:
 
 ##### Deposits
 
+```python
+def get_validator_from_deposit(state: BeaconState, deposit: Deposit) -> Validator:
+    amount = deposit.data.amount
+    effective_balance = min(amount - amount % EFFECTIVE_BALANCE_INCREMENT, MAX_EFFECTIVE_BALANCE)
+
+    return Validator(
+        pubkey=deposit.data.pubkey,
+        withdrawal_credentials=deposit.data.withdrawal_credentials,
+        activation_eligibility_epoch=FAR_FUTURE_EPOCH,
+        activation_epoch=FAR_FUTURE_EPOCH,
+        exit_epoch=FAR_FUTURE_EPOCH,
+        withdrawable_epoch=FAR_FUTURE_EPOCH,
+        effective_balance=effective_balance,
+    )
+```
+
 ```python
 def process_deposit(state: BeaconState, deposit: Deposit) -> None:
     # Verify the Merkle branch
@@ -1778,15 +1794,7 @@ def process_deposit(state: BeaconState, deposit: Deposit) -> None:
             return
 
         # Add validator and balance entries
-        state.validators.append(Validator(
-            pubkey=pubkey,
-            withdrawal_credentials=deposit.data.withdrawal_credentials,
-            activation_eligibility_epoch=FAR_FUTURE_EPOCH,
-            activation_epoch=FAR_FUTURE_EPOCH,
-            exit_epoch=FAR_FUTURE_EPOCH,
-            withdrawable_epoch=FAR_FUTURE_EPOCH,
-            effective_balance=min(amount - amount % EFFECTIVE_BALANCE_INCREMENT, MAX_EFFECTIVE_BALANCE),
-        ))
+        state.validators.append(get_validator_from_deposit(state, deposit))
         state.balances.append(amount)
     else:
         # Increase balance by deposit amount