[CHIA-3793] after the hard fork, disallow block references

chia/_tests/conftest.py

@@ -200,7 +200,8 @@ class ConsensusMode(ComparableEnum):
 
 @pytest.fixture(
     scope="session",
-    params=[ConsensusMode.PLAIN, ConsensusMode.HARD_FORK_2_0, ConsensusMode.HARD_FORK_3_0],
+    # TODO: todo_v2_plots add HARD_FORK_3_0 mode as well as after phase-out
+    params=[ConsensusMode.PLAIN, ConsensusMode.HARD_FORK_2_0],
 )
 def consensus_mode(request):
     return request.param

chia/_tests/core/server/test_rate_limits.py

@@ -24,7 +24,6 @@
 rl_v2 = [Capability.BASE, Capability.BLOCK_HEADERS, Capability.RATE_LIMITS_V2]
 rl_v1 = [Capability.BASE]
 node_with_params_b = node_with_params
-test_different_versions_results: list[int] = []
 
 
 @dataclass
@@ -418,11 +417,14 @@ async def test_different_versions(
     # The following code checks whether all of the runs resulted in the same number of items in "rate_limits_tx",
     # which would mean the same rate limits are always used. This should not happen, since two nodes with V2
     # will use V2.
-    total_tx_msg_count = len(get_rate_limits_to_use(a_con.local_capabilities, a_con.peer_capabilities))
+    rate_limits = get_rate_limits_to_use(a_con.local_capabilities, a_con.peer_capabilities)[0]
+    limit = rate_limits[ProtocolMessageTypes.request_header_blocks]
+    assert isinstance(limit, RLSettings)
 
-    test_different_versions_results.append(total_tx_msg_count)
-    if len(test_different_versions_results) >= 4:
-        assert len(set(test_different_versions_results)) >= 2
+    if Capability.RATE_LIMITS_V2 in a_con.local_capabilities and Capability.RATE_LIMITS_V2 in a_con.peer_capabilities:
+        assert limit.frequency == 5000
+    else:
+        assert limit.frequency == 500
 
 
 @pytest.mark.anyio

chia/consensus/block_body_validation.py

@@ -341,10 +341,14 @@ async def validate_block_body(
     #     the generator ref list for this block (or 'one' bytes [0x01] if no generator)
     # 8b. The generator ref list length must be less than or equal to MAX_GENERATOR_REF_LIST_SIZE entries
     # 8c. The generator ref list must not point to a height >= this block's height
-    if block.transactions_generator_ref_list in (None, []):
+    if block.transactions_generator_ref_list == []:
         if block.transactions_info.generator_refs_root != bytes([1] * 32):
             return Err.INVALID_TRANSACTIONS_GENERATOR_REFS_ROOT
     else:
+        # With hard fork 2 we ban transactions_generator_ref_list.
+        if prev_transaction_block_height >= constants.HARD_FORK2_HEIGHT:
+            return Err.TOO_MANY_GENERATOR_REFS
+
         # If we have a generator reference list, we must have a generator
         if block.transactions_generator is None:
             return Err.INVALID_TRANSACTIONS_GENERATOR_REFS_ROOT

chia/consensus/blockchain.py

@@ -33,6 +33,7 @@
 from chia.consensus.find_fork_point import lookup_fork_chain
 from chia.consensus.full_block_to_block_record import block_to_block_record
 from chia.consensus.generator_tools import get_block_header
+from chia.consensus.get_block_challenge import prev_tx_block
 from chia.consensus.get_block_generator import get_block_generator
 from chia.consensus.multiprocess_validation import PreValidationResult
 from chia.full_node.block_store import BlockStore
@@ -698,12 +699,16 @@ async def validate_unfinished_block_header(
         if len(block.transactions_generator_ref_list) > self.constants.MAX_GENERATOR_REF_LIST_SIZE:
             return None, Err.TOO_MANY_GENERATOR_REFS
 
-        if (
-            self.try_block_record(block.prev_header_hash) is None
-            and block.prev_header_hash != self.constants.GENESIS_CHALLENGE
-        ):
+        prev_b = self.try_block_record(block.prev_header_hash)
+        if prev_b is None and block.prev_header_hash != self.constants.GENESIS_CHALLENGE:
             return None, Err.INVALID_PREV_BLOCK_HASH
 
+        prev_tx_height = prev_tx_block(self, prev_b)
+
+        # With hard fork 2 we ban transactions_generator_ref_list.
+        if prev_tx_height >= self.constants.HARD_FORK2_HEIGHT and block.transactions_generator_ref_list != []:
+            return None, Err.TOO_MANY_GENERATOR_REFS
+
         if block.transactions_info is not None:
             if block.transactions_generator is not None:
                 if std_hash(bytes(block.transactions_generator)) != block.transactions_info.generator_root:

chia/simulator/block_tools.py

@@ -385,6 +385,10 @@ def setup_new_gen(
         transaction_data: Optional[SpendBundle],
         block_refs: list[uint32],
     ) -> Optional[NewBlockGenerator]:
+        if prev_tx_height >= self.constants.HARD_FORK2_HEIGHT:
+            assert block_refs == [], "block references are not allowed after hard fork 2"
+            dummy_block_references = False
+
         # we don't know if the new block will be a transaction
         # block or not, so even though we prepare a block
         # generator, we can't update our state (like,