EIP-7594: PeerDAS explicit csc integer size (#3897)

* EIP-7594: PeerDAS explicit csc integer size

* add spec test for csc int size

* import uint8

* make linter happy

* add spec

* Update p2p-interface.md

* Update specs/_features/eip7594/das-core.md

Co-authored-by: Justin Traglia <[email protected]>

* revert metadata name

* Update specs/_features/eip7594/das-core.md

Co-authored-by: Justin Traglia <[email protected]>

* update tests

* make linter happy

* Make `DATA_COLUMN_SIDECAR_SUBNET_COUNT` in uint8

* add `int` casting for bypassing remerkeable type conversion

---------

Co-authored-by: Justin Traglia <[email protected]>
Co-authored-by: Hsiao-Wei Wang <[email protected]>

Author: 3 people

scripts/build_run_docker_tests.sh

@@ -10,7 +10,7 @@
 
 
 # Set variables
-ALL_EXECUTABLE_SPECS=("phase0" "altair" "bellatrix" "capella" "deneb" "electra" "whisk")
+ALL_EXECUTABLE_SPECS=("phase0" "altair" "bellatrix" "capella" "deneb" "electra" "whisk" "eip7594")
 TEST_PRESET_TYPE=minimal
 FORK_TO_TEST=phase0
 WORKDIR="//consensus-specs//tests//core//pyspec"

specs/_features/eip7594/das-core.md

@@ -67,7 +67,7 @@ The following values are (non-configurable) constants used throughout the specif
 
 | Name | Value | Description |
 | - | - | - |
-| `DATA_COLUMN_SIDECAR_SUBNET_COUNT` | `128` | The number of data column sidecar subnets used in the gossipsub protocol |
+| `DATA_COLUMN_SIDECAR_SUBNET_COUNT` | `uint8(128)` | The number of data column sidecar subnets used in the gossipsub protocol |
 
 ### Custody setting
 
@@ -105,15 +105,15 @@ class MatrixEntry(Container):
 ### `get_custody_columns`
 
 ```python
-def get_custody_columns(node_id: NodeID, custody_subnet_count: uint64) -> Sequence[ColumnIndex]:
+def get_custody_columns(node_id: NodeID, custody_subnet_count: uint8) -> Sequence[ColumnIndex]:
     assert custody_subnet_count <= DATA_COLUMN_SIDECAR_SUBNET_COUNT
 
     subnet_ids: List[uint64] = []
     current_id = uint256(node_id)
     while len(subnet_ids) < custody_subnet_count:
         subnet_id = (
             bytes_to_uint64(hash(uint_to_bytes(uint256(current_id)))[0:8])
-            % DATA_COLUMN_SIDECAR_SUBNET_COUNT
+            % int(DATA_COLUMN_SIDECAR_SUBNET_COUNT)
         )
         if subnet_id not in subnet_ids:
             subnet_ids.append(subnet_id)
@@ -124,9 +124,9 @@ def get_custody_columns(node_id: NodeID, custody_subnet_count: uint64) -> Sequen
 
     assert len(subnet_ids) == len(set(subnet_ids))
 
-    columns_per_subnet = NUMBER_OF_COLUMNS // DATA_COLUMN_SIDECAR_SUBNET_COUNT
+    columns_per_subnet = NUMBER_OF_COLUMNS // int(DATA_COLUMN_SIDECAR_SUBNET_COUNT)
     return sorted([
-        ColumnIndex(DATA_COLUMN_SIDECAR_SUBNET_COUNT * i + subnet_id)
+        ColumnIndex(int(DATA_COLUMN_SIDECAR_SUBNET_COUNT) * i + subnet_id)
         for i in range(columns_per_subnet)
         for subnet_id in subnet_ids
     ])
@@ -222,7 +222,7 @@ def get_data_column_sidecars(signed_block: SignedBeaconBlock,
 
 Each node downloads and custodies a minimum of `CUSTODY_REQUIREMENT` subnets per slot. The particular subnets that the node is required to custody are selected pseudo-randomly (more on this below).
 
-A node *may* choose to custody and serve more than the minimum honesty requirement. Such a node explicitly advertises a number greater than `CUSTODY_REQUIREMENT` via the peer discovery mechanism -- for example, in their ENR (e.g. `custody_subnet_count: 4` if the node custodies `4` subnets each slot) -- up to a `DATA_COLUMN_SIDECAR_SUBNET_COUNT` (i.e. a super-full node).
+A node *may* choose to custody and serve more than the minimum honesty requirement. Such a node explicitly advertises a number greater than `CUSTODY_REQUIREMENT` through the peer discovery mechanism, specifically by setting a higher value in the `custody_subnet_count` field within its ENR. This value can be increased up to `DATA_COLUMN_SIDECAR_SUBNET_COUNT`, indicating a super-full node.
 
 A node stores the custodied columns for the duration of the pruning period and responds to peer requests for samples on those columns.
 

specs/_features/eip7594/p2p-interface.md

@@ -119,14 +119,14 @@ The `MetaData` stored locally by clients is updated with an additional field to
   seq_number: uint64
   attnets: Bitvector[ATTESTATION_SUBNET_COUNT]
   syncnets: Bitvector[SYNC_COMMITTEE_SUBNET_COUNT]
-  custody_subnet_count: uint64
+  custody_subnet_count: uint8 # csc
 )
 ```
 
 Where
 
 - `seq_number`, `attnets`, and `syncnets` have the same meaning defined in the Altair document.
-- `custody_subnet_count` represents the node's custody subnet count. Clients MAY reject ENRs with a value less than `CUSTODY_REQUIREMENT`.
+- `csc` represents the node's custody subnet count. Clients MAY reject ENRs with a value less than `CUSTODY_REQUIREMENT`.
 
 ### The gossip domain: gossipsub
 
@@ -322,6 +322,6 @@ Requests the MetaData of a peer, using the new `MetaData` definition given above
 
 A new field is added to the ENR under the key `csc` to facilitate custody data column discovery.
 
-| Key    | Value                                    |
-|--------|------------------------------------------|
-| `csc`  | Custody subnet count, big endian integer |
+| Key    | Value                               |
+|--------|-------------------------------------|
+| `csc`  | Custody subnet count, uint8 integer |

tests/core/pyspec/eth2spec/test/eip7594/networking/test_get_custody_columns.py

@@ -20,7 +20,7 @@ def _run_get_custody_columns(spec, rng, node_id=None, custody_subnet_count=None)
 
     assert len(result) == len(set(result))
     assert len(result) == (
-        custody_subnet_count * spec.config.NUMBER_OF_COLUMNS // spec.config.DATA_COLUMN_SIDECAR_SUBNET_COUNT
+        int(custody_subnet_count) * spec.config.NUMBER_OF_COLUMNS // int(spec.config.DATA_COLUMN_SIDECAR_SUBNET_COUNT)
     )
     assert all(i < spec.config.NUMBER_OF_COLUMNS for i in result)
     python_list_result = [int(i) for i in result]

tests/core/pyspec/eth2spec/test/eip7594/unittests/test_config_invariants.py

@@ -3,6 +3,7 @@
     spec_test,
     with_eip7594_and_later,
 )
+from eth2spec.utils.ssz.ssz_typing import uint8
 
 
 @with_eip7594_and_later
@@ -12,9 +13,10 @@ def test_invariants(spec):
     assert spec.FIELD_ELEMENTS_PER_BLOB % spec.FIELD_ELEMENTS_PER_CELL == 0
     assert spec.FIELD_ELEMENTS_PER_EXT_BLOB % spec.config.NUMBER_OF_COLUMNS == 0
     assert spec.config.SAMPLES_PER_SLOT <= spec.config.NUMBER_OF_COLUMNS
+    assert spec.config.NUMBER_OF_COLUMNS == uint8(spec.config.NUMBER_OF_COLUMNS)  # ENR field is uint8
     assert spec.config.CUSTODY_REQUIREMENT <= spec.config.DATA_COLUMN_SIDECAR_SUBNET_COUNT
     assert spec.config.DATA_COLUMN_SIDECAR_SUBNET_COUNT <= spec.config.NUMBER_OF_COLUMNS
-    assert spec.config.NUMBER_OF_COLUMNS % spec.config.DATA_COLUMN_SIDECAR_SUBNET_COUNT == 0
+    assert spec.config.NUMBER_OF_COLUMNS % int(spec.config.DATA_COLUMN_SIDECAR_SUBNET_COUNT) == 0
     assert spec.config.MAX_REQUEST_DATA_COLUMN_SIDECARS == (
         spec.config.MAX_REQUEST_BLOCKS_DENEB * spec.config.NUMBER_OF_COLUMNS
     )

tests/core/pyspec/eth2spec/test/eip7594/unittests/test_custody.py

@@ -9,9 +9,9 @@
 def run_get_custody_columns(spec, peer_count, custody_subnet_count):
     assignments = [spec.get_custody_columns(node_id, custody_subnet_count) for node_id in range(peer_count)]
 
-    columns_per_subnet = spec.config.NUMBER_OF_COLUMNS // spec.config.DATA_COLUMN_SIDECAR_SUBNET_COUNT
+    columns_per_subnet = spec.config.NUMBER_OF_COLUMNS // int(spec.config.DATA_COLUMN_SIDECAR_SUBNET_COUNT)
     for assignment in assignments:
-        assert len(assignment) == custody_subnet_count * columns_per_subnet
+        assert len(assignment) == int(custody_subnet_count) * columns_per_subnet
         assert len(assignment) == len(set(assignment))