feat(script): deprecate unnecessary opcodes

Author: glevco

.yamllint.yml

@@ -1,5 +1,8 @@
 extends: default
 
+ignore:
+  - .venv/
+
 rules:
   document-start: disable
   line-length:

hathor/conf/settings.py

@@ -485,6 +485,9 @@ def GENESIS_TX2_TIMESTAMP(self) -> int:
     # Used to enable fee-based tokens.
     ENABLE_FEE_BASED_TOKENS: FeatureSetting = FeatureSetting.DISABLED
 
+    # Used to enable opcodes V2.
+    ENABLE_OPCODES_V2: FeatureSetting = FeatureSetting.DISABLED
+
     # List of enabled blueprints.
     BLUEPRINTS: dict[bytes, str] = {}
 

hathor/conf/unittests.yml

@@ -25,6 +25,7 @@ FEATURE_ACTIVATION:
 
 ENABLE_NANO_CONTRACTS: enabled
 ENABLE_FEE_BASED_TOKENS: enabled
+ENABLE_OPCODES_V2: enabled
 
 NC_ON_CHAIN_BLUEPRINT_ALLOWED_ADDRESSES:
   # keypair wallet:

hathor/consensus/consensus.py

@@ -30,6 +30,7 @@
 from hathor.transaction import BaseTransaction, Block, Transaction
 from hathor.transaction.exceptions import RewardLocked
 from hathor.util import not_none
+from hathor.verification.verification_params import VerificationParams
 
 if TYPE_CHECKING:
     from hathor.conf.settings import HathorSettings
@@ -427,6 +428,9 @@ def _feature_activation_rules(self, tx: Transaction, old_best_block: Block, new_
                 case Feature.COUNT_CHECKDATASIG_OP:
                     if not self._checkdatasig_count_rule(tx):
                         return False
+                case Feature.OPCODES_V2:
+                    if not self._opcodes_v2_activation_rule(tx, is_active, new_best_block):
+                        return False
                 case (
                     Feature.INCREASE_MAX_MERKLE_PATH_LENGTH
                     | Feature.NOP_FEATURE_1
@@ -489,6 +493,35 @@ def _checkdatasig_count_rule(self, tx: Transaction) -> bool:
             return False
         return True
 
+    def _opcodes_v2_activation_rule(self, tx: Transaction, is_active: bool, new_best_block: Block) -> bool:
+        """
+        Check whether a tx became invalid because the reorg changed the opcodes V2 feature activation state.
+        """
+        from hathor.verification.nano_header_verifier import NanoHeaderVerifier
+        from hathor.verification.transaction_verifier import TransactionVerifier
+
+        if not is_active:
+            # When the feature is not active, this rule has no effect.
+            return True
+
+        params = VerificationParams.default_for_mempool(best_block=new_best_block)
+
+        # Any exception in the inputs verification will be considered
+        # a fail and the tx will be removed from the mempool.
+        try:
+            TransactionVerifier._verify_inputs(self._settings, tx, params, skip_script=False)
+        except Exception:
+            return False
+
+        # Any exception in the nc_signature verification will be considered
+        # a fail and the tx will be removed from the mempool.
+        try:
+            NanoHeaderVerifier._verify_nc_signature(self._settings, tx, params)
+        except Exception:
+            return False
+
+        return True
+
     def _feature_activation_flips(self, *, old_best_block: Block, new_best_block: Block) -> dict[Feature, bool]:
         """
         Get a diff of feature activation states that flipped from active to non-active,

hathor/feature_activation/feature.py

@@ -32,3 +32,4 @@ class Feature(StrEnum):
     COUNT_CHECKDATASIG_OP = 'COUNT_CHECKDATASIG_OP'
     NANO_CONTRACTS = 'NANO_CONTRACTS'
     FEE_TOKENS = 'FEE_TOKENS'
+    OPCODES_V2 = 'OPCODES_V2'

hathor/feature_activation/utils.py

@@ -19,6 +19,7 @@
 
 from hathor.feature_activation.feature import Feature
 from hathor.feature_activation.model.feature_state import FeatureState
+from hathor.transaction.scripts.opcode import OpcodesVersion
 
 if TYPE_CHECKING:
     from hathor.conf.settings import FeatureSetting, HathorSettings
@@ -33,6 +34,7 @@ class Features:
     count_checkdatasig_op: bool
     nano: bool
     fee_tokens: bool
+    opcodes_version: OpcodesVersion
 
     @staticmethod
     def from_vertex(*, settings: HathorSettings, feature_service: FeatureService, vertex: Vertex) -> Features:
@@ -43,17 +45,21 @@ def from_vertex(*, settings: HathorSettings, feature_service: FeatureService, ve
             Feature.COUNT_CHECKDATASIG_OP: FeatureSetting.FEATURE_ACTIVATION,
             Feature.NANO_CONTRACTS: settings.ENABLE_NANO_CONTRACTS,
             Feature.FEE_TOKENS: settings.ENABLE_FEE_BASED_TOKENS,
+            Feature.OPCODES_V2: settings.ENABLE_OPCODES_V2,
         }
 
-        features = {
+        feature_is_active: dict[Feature, bool] = {
             feature: _is_feature_active(setting, feature_states.get(feature, FeatureState.DEFINED))
             for feature, setting in feature_settings.items()
         }
 
+        opcodes_version = OpcodesVersion.V2 if feature_is_active[Feature.OPCODES_V2] else OpcodesVersion.V1
+
         return Features(
-            count_checkdatasig_op=features[Feature.COUNT_CHECKDATASIG_OP],
-            nano=features[Feature.NANO_CONTRACTS],
-            fee_tokens=features[Feature.FEE_TOKENS],
+            count_checkdatasig_op=feature_is_active[Feature.COUNT_CHECKDATASIG_OP],
+            nano=feature_is_active[Feature.NANO_CONTRACTS],
+            fee_tokens=feature_is_active[Feature.FEE_TOKENS],
+            opcodes_version=opcodes_version,
         )
 
 

hathor/nanocontracts/types.py

@@ -32,6 +32,7 @@
 from hathor.nanocontracts.exception import BlueprintSyntaxError, NCSerializationError
 from hathor.nanocontracts.faux_immutable import FauxImmutableMeta
 from hathor.serialization import SerializationError
+from hathor.transaction.scripts.opcode import OpcodesVersion
 from hathor.transaction.util import bytes_to_int, get_deposit_token_withdraw_amount, int_to_bytes
 from hathor.utils.typing import InnerTypeMixin
 
@@ -162,7 +163,7 @@ def checksig(self, script: bytes) -> bool:
         from hathor.transaction.exceptions import ScriptError
         from hathor.transaction.scripts import ScriptExtras
         from hathor.transaction.scripts.execute import raw_script_eval
-        extras = ScriptExtras(tx=self)  # type: ignore[arg-type]
+        extras = ScriptExtras(tx=self, version=OpcodesVersion.V2)  # type: ignore[arg-type]
         try:
             raw_script_eval(input_data=self.script_input, output_script=script, extras=extras)
         except ScriptError:

hathor/p2p/sync_v2/transaction_streaming_client.py

@@ -28,6 +28,7 @@
 from hathor.p2p.sync_v2.streamers import StreamEnd
 from hathor.transaction import BaseTransaction, Transaction
 from hathor.transaction.exceptions import HathorError, TxValidationError
+from hathor.transaction.scripts.opcode import OpcodesVersion
 from hathor.types import VertexId
 from hathor.verification.verification_params import VerificationParams
 
@@ -59,6 +60,7 @@ def __init__(self,
                 count_checkdatasig_op=False,
                 nano=False,
                 fee_tokens=False,
+                opcodes_version=OpcodesVersion.V1,
             )
         )
 

hathor/transaction/resources/create_tx.py

@@ -22,6 +22,7 @@
 from hathor.transaction import Transaction, TxInput, TxOutput
 from hathor.transaction.scripts import create_output_script
 from hathor.util import api_catch_exceptions, json_dumpb, json_loadb
+from hathor.verification.verification_params import VerificationParams
 
 
 def from_raw_output(raw_output: dict, tokens: list[bytes]) -> TxOutput:
@@ -116,11 +117,12 @@ def _verify_unsigned_skip_pow(self, tx: Transaction) -> None:
         verifiers.tx.verify_output_token_indexes(tx)
         verifiers.vertex.verify_sigops_output(tx, enable_checkdatasig_count=True)
         verifiers.tx.verify_sigops_input(tx, enable_checkdatasig_count=True)
+        best_block = self.manager.tx_storage.get_best_block()
+        params = VerificationParams.default_for_mempool(best_block=best_block)
         # need to run verify_inputs first to check if all inputs exist
-        verifiers.tx.verify_inputs(tx, skip_script=True)
+        verifiers.tx.verify_inputs(tx, params, skip_script=True)
         verifiers.vertex.verify_parents(tx)
 
-        best_block = self.manager.tx_storage.get_best_block()
         block_storage = self.manager.get_nc_block_storage(best_block)
         verifiers.tx.verify_sum(self.manager._settings, tx, tx.get_complete_token_info(block_storage))
 

hathor/transaction/scripts/execute.py

@@ -12,17 +12,23 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 
+from __future__ import annotations
+
 import struct
 from dataclasses import dataclass
-from typing import NamedTuple, Optional, Union
+from typing import TYPE_CHECKING, NamedTuple, Optional, Union
 
 from hathor.transaction import BaseTransaction, Transaction, TxInput
 from hathor.transaction.exceptions import DataIndexError, FinalStackInvalid, InvalidScriptError, OutOfData
 
+if TYPE_CHECKING:
+    from hathor.transaction.scripts.opcode import OpcodesVersion
+
 
 @dataclass(slots=True, frozen=True, kw_only=True)
 class ScriptExtras:
     tx: Transaction
+    version: OpcodesVersion
 
 
 @dataclass(slots=True, frozen=True, kw_only=True)
@@ -72,7 +78,7 @@ def execute_eval(data: bytes, log: list[str], extras: ScriptExtras) -> None:
             continue
 
         # this is an opcode manipulating the stack
-        execute_op_code(Opcode(opcode), context)
+        execute_op_code(Opcode(opcode), context, extras.version)
 
     evaluate_final_stack(stack, log)
 
@@ -94,7 +100,7 @@ def evaluate_final_stack(stack: Stack, log: list[str]) -> None:
         raise FinalStackInvalid('\n'.join(log))
 
 
-def script_eval(tx: Transaction, txin: TxInput, spent_tx: BaseTransaction) -> None:
+def script_eval(tx: Transaction, txin: TxInput, spent_tx: BaseTransaction, version: OpcodesVersion) -> None:
     """Evaluates the output script and input data according to
     a very limited subset of Bitcoin's scripting language.
 
@@ -112,7 +118,7 @@ def script_eval(tx: Transaction, txin: TxInput, spent_tx: BaseTransaction) -> No
     raw_script_eval(
         input_data=txin.data,
         output_script=spent_tx.outputs[txin.index].script,
-        extras=UtxoScriptExtras(tx=tx, txin=txin, spent_tx=spent_tx),
+        extras=UtxoScriptExtras(tx=tx, txin=txin, spent_tx=spent_tx, version=version),
     )