[PAN-2829] - add hooks for validation (#1671)

EIP-1602 specifies a new validation step.  Add hooks for those to occur.
Move contract size checking into the validation hooks.

Signed-off-by: Adrian Sutton <adrian.sutton@consensys.net>

errorprone-checks/build.gradle

@@ -42,6 +42,4 @@ dependencies {
   epJavac 'com.google.errorprone:error_prone_check_api'
 }
 
-test {
-  testLogging { showStandardStreams = true }
-}
+test { testLogging { showStandardStreams = true } }

ethereum/core/src/main/java/tech/pegasys/pantheon/ethereum/mainnet/ContractValidationRule.java

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2019 ConsenSys AG.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
+ * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License.
+ */
+package tech.pegasys.pantheon.ethereum.mainnet;
+
+import tech.pegasys.pantheon.ethereum.vm.MessageFrame;
+
+@FunctionalInterface
+public interface ContractValidationRule {
+
+  boolean validate(MessageFrame frame);
+}

ethereum/core/src/main/java/tech/pegasys/pantheon/ethereum/mainnet/MainnetContractCreationProcessor.java

@@ -22,6 +22,7 @@ import tech.pegasys.pantheon.ethereum.vm.MessageFrame;
 import tech.pegasys.pantheon.util.bytes.BytesValue;
 
 import java.util.Collection;
+import java.util.List;
 
 import com.google.common.collect.ImmutableSet;
 import org.apache.logging.log4j.LogManager;
@@ -38,7 +39,7 @@ public class MainnetContractCreationProcessor extends AbstractMessageProcessor {
 
   private final long initialContractNonce;
 
-  private final int codeSizeLimit;
+  private final List<ContractValidationRule> contractValidationRules;
 
   private final int accountVersion;
 
@@ -46,14 +47,14 @@ public class MainnetContractCreationProcessor extends AbstractMessageProcessor {
       final GasCalculator gasCalculator,
       final EVM evm,
       final boolean requireCodeDepositToSucceed,
-      final int codeSizeLimit,
+      final List<ContractValidationRule> contractValidationRules,
       final long initialContractNonce,
       final Collection<Address> forceCommitAddresses,
       final int accountVersion) {
     super(evm, forceCommitAddresses);
     this.gasCalculator = gasCalculator;
     this.requireCodeDepositToSucceed = requireCodeDepositToSucceed;
-    this.codeSizeLimit = codeSizeLimit;
+    this.contractValidationRules = contractValidationRules;
     this.initialContractNonce = initialContractNonce;
     this.accountVersion = accountVersion;
   }
@@ -62,14 +63,14 @@ public class MainnetContractCreationProcessor extends AbstractMessageProcessor {
       final GasCalculator gasCalculator,
       final EVM evm,
       final boolean requireCodeDepositToSucceed,
-      final int codeSizeLimit,
+      final List<ContractValidationRule> contractValidationRules,
       final long initialContractNonce,
       final Collection<Address> forceCommitAddresses) {
     this(
         gasCalculator,
         evm,
         requireCodeDepositToSucceed,
-        codeSizeLimit,
+        contractValidationRules,
         initialContractNonce,
         forceCommitAddresses,
         Account.DEFAULT_VERSION);
@@ -79,13 +80,13 @@ public class MainnetContractCreationProcessor extends AbstractMessageProcessor {
       final GasCalculator gasCalculator,
       final EVM evm,
       final boolean requireCodeDepositToSucceed,
-      final int codeSizeLimit,
+      final List<ContractValidationRule> contractValidationRules,
       final long initialContractNonce) {
     this(
         gasCalculator,
         evm,
         requireCodeDepositToSucceed,
-        codeSizeLimit,
+        contractValidationRules,
         initialContractNonce,
         ImmutableSet.of(),
         Account.DEFAULT_VERSION);
@@ -140,13 +141,7 @@ public class MainnetContractCreationProcessor extends AbstractMessageProcessor {
         frame.setState(MessageFrame.State.COMPLETED_SUCCESS);
       }
     } else {
-      if (contractCode.size() > codeSizeLimit) {
-        LOG.trace(
-            "Contract creation error: code size {} exceeds code size limit {}",
-            contractCode.size(),
-            codeSizeLimit);
-        frame.setState(MessageFrame.State.EXCEPTIONAL_HALT);
-      } else {
+      if (contractValidationRules.stream().allMatch(rule -> rule.validate(frame))) {
         frame.decrementRemainingGas(depositFee);
 
         // Finalize contract creation, setting the contract code.
@@ -160,6 +155,8 @@ public class MainnetContractCreationProcessor extends AbstractMessageProcessor {
             contractCode.size(),
             frame.getRemainingGas());
         frame.setState(MessageFrame.State.COMPLETED_SUCCESS);
+      } else {
+        frame.setState(MessageFrame.State.EXCEPTIONAL_HALT);
       }
     }
   }

ethereum/core/src/main/java/tech/pegasys/pantheon/ethereum/mainnet/MainnetProtocolSpecs.java

@@ -25,11 +25,13 @@ import tech.pegasys.pantheon.ethereum.core.TransactionReceipt;
 import tech.pegasys.pantheon.ethereum.core.Wei;
 import tech.pegasys.pantheon.ethereum.core.WorldState;
 import tech.pegasys.pantheon.ethereum.core.WorldUpdater;
+import tech.pegasys.pantheon.ethereum.mainnet.contractvalidation.MaxCodeSizeRule;
 import tech.pegasys.pantheon.ethereum.privacy.PrivateTransactionProcessor;
 
 import java.io.IOException;
 import java.math.BigInteger;
 import java.nio.charset.StandardCharsets;
+import java.util.Collections;
 import java.util.List;
 import java.util.Optional;
 import java.util.OptionalInt;
@@ -76,7 +78,11 @@ public abstract class MainnetProtocolSpecs {
         .contractCreationProcessorBuilder(
             (gasCalculator, evm) ->
                 new MainnetContractCreationProcessor(
-                    gasCalculator, evm, false, contractSizeLimit, 0))
+                    gasCalculator,
+                    evm,
+                    false,
+                    Collections.singletonList(MaxCodeSizeRule.of(contractSizeLimit)),
+                    0))
         .transactionValidatorBuilder(
             gasCalculator ->
                 new MainnetTransactionValidator(gasCalculator, false, Optional.empty()))
@@ -128,7 +134,11 @@ public abstract class MainnetProtocolSpecs {
         .contractCreationProcessorBuilder(
             (gasCalculator, evm) ->
                 new MainnetContractCreationProcessor(
-                    gasCalculator, evm, true, contractSizeLimit, 0))
+                    gasCalculator,
+                    evm,
+                    true,
+                    Collections.singletonList(MaxCodeSizeRule.of(contractSizeLimit)),
+                    0))
         .transactionValidatorBuilder(
             gasCalculator -> new MainnetTransactionValidator(gasCalculator, true, Optional.empty()))
         .difficultyCalculator(MainnetDifficultyCalculators.HOMESTEAD)
@@ -189,7 +199,7 @@ public abstract class MainnetProtocolSpecs {
                     gasCalculator,
                     evm,
                     true,
-                    contractSizeLimit,
+                    Collections.singletonList(MaxCodeSizeRule.of(contractSizeLimit)),
                     1,
                     SPURIOUS_DRAGON_FORCE_DELETE_WHEN_EMPTY_ADDRESSES))
         .transactionValidatorBuilder(
@@ -278,7 +288,7 @@ public abstract class MainnetProtocolSpecs {
                     gasCalculator,
                     evm,
                     true,
-                    contractSizeLimit,
+                    Collections.singletonList(MaxCodeSizeRule.of(contractSizeLimit)),
                     1,
                     SPURIOUS_DRAGON_FORCE_DELETE_WHEN_EMPTY_ADDRESSES,
                     1))

ethereum/core/src/main/java/tech/pegasys/pantheon/ethereum/mainnet/contractvalidation/MaxCodeSizeRule.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright 2019 ConsenSys AG.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
+ * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License.
+ */
+package tech.pegasys.pantheon.ethereum.mainnet.contractvalidation;
+
+import tech.pegasys.pantheon.ethereum.mainnet.ContractValidationRule;
+import tech.pegasys.pantheon.ethereum.vm.MessageFrame;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+public class MaxCodeSizeRule implements ContractValidationRule {
+
+  private static final Logger LOG = LogManager.getLogger();
+
+  private final int maxCodeSize;
+
+  private MaxCodeSizeRule(final int maxCodeSize) {
+    this.maxCodeSize = maxCodeSize;
+  }
+
+  @Override
+  public boolean validate(final MessageFrame frame) {
+    final int contractCodeSize = frame.getOutputData().size();
+    if (contractCodeSize <= maxCodeSize) {
+      return true;
+    } else {
+      LOG.trace(
+          "Contract creation error: code size {} exceeds code size limit {}",
+          contractCodeSize,
+          maxCodeSize);
+      return false;
+    }
+  }
+
+  public static ContractValidationRule of(final int maxCodeSize) {
+    return new MaxCodeSizeRule(maxCodeSize);
+  }
+}