[EC-302] Adding maximum gasLimit validation

src/it/scala/io/iohk/ethereum/txExecTest/ForksTest.scala

@@ -17,7 +17,7 @@ class ForksTest extends FlatSpec with Matchers {
     override val eip150BlockNumber: BigInt = 5
     override val eip160BlockNumber: BigInt = 7
     override val eip155BlockNumber: BigInt = 0
-
+    override val eip106BlockNumber: BigInt = Long.MaxValue
     override val chainId: Byte = 0x3d
     override val monetaryPolicyConfig: MonetaryPolicyConfig = MonetaryPolicyConfig(5000000, 0.2, 5000000000000000000L)
 

src/main/resources/application.conf

@@ -206,6 +206,10 @@ mantis {
     # Doc: https://github.com/ethereum/EIPs/blob/master/EIPS/eip-2.md
     homestead-block-number = "1150000"
 
+    # EIP-106 fork block number
+    # Doc: https://github.com/ethereum/EIPs/issues/106
+    eip106-block-number = "9223372036854775807"
+
     # EIP-150 fork block number
     # Doc: https://github.com/ethereum/EIPs/issues/150
     eip150-block-number = "2500000"

src/main/scala/io/iohk/ethereum/utils/Config.scala

@@ -244,6 +244,7 @@ trait BlockchainConfig {
   val eip150BlockNumber: BigInt
   val eip155BlockNumber: BigInt
   val eip160BlockNumber: BigInt
+  val eip106BlockNumber: BigInt
   val difficultyBombPauseBlockNumber: BigInt
   val difficultyBombContinueBlockNumber: BigInt
 
@@ -285,6 +286,8 @@ object BlockchainConfig {
       }
 
       override val monetaryPolicyConfig = MonetaryPolicyConfig(blockchainConfig.getConfig("monetary-policy"))
+
+      override val eip106BlockNumber: BigInt = BigInt(blockchainConfig.getString("eip106-block-number"))
     }
   }
 }

src/main/scala/io/iohk/ethereum/validators/BlockHeaderValidator.scala

@@ -18,6 +18,7 @@ class BlockHeaderValidatorImpl(blockchainConfig: BlockchainConfig) extends Block
   val GasLimitBoundDivisor: Int = 1024
   val MinGasLimit: BigInt = 5000 //Although the paper states this value is 125000, on the different clients 5000 is used
   val difficulty = new DifficultyCalculator(blockchainConfig)
+  val MaxGasLimit = Long.MaxValue // max gasLimit is equal 2^63-1 according to EIP106
   import BlockHeaderError._
 
   /** This method allows validate a BlockHeader (stated on
@@ -101,15 +102,24 @@ class BlockHeaderValidatorImpl(blockchainConfig: BlockchainConfig) extends Block
     * Validates [[io.iohk.ethereum.domain.BlockHeader.gasLimit]] follows the restrictions based on its parent gasLimit
     * based on validations stated in section 4.4.4 of http://paper.gavwood.com/
     *
+    * EIP106(https://github.com/ethereum/EIPs/issues/106) adds additional validation of maximum value for gasLimit.
+    *
     * @param blockHeader BlockHeader to validate.
     * @param parentHeader BlockHeader of the parent of the block to validate.
     * @return BlockHeader if valid, an [[HeaderGasLimitError]] otherwise
     */
   private def validateGasLimit(blockHeader: BlockHeader, parentHeader: BlockHeader): Either[BlockHeaderError, BlockHeader] = {
-    val gasLimitDiff = (blockHeader.gasLimit - parentHeader.gasLimit).abs
-    val gasLimitDiffLimit = parentHeader.gasLimit / GasLimitBoundDivisor
-    if(gasLimitDiff < gasLimitDiffLimit && blockHeader.gasLimit >= MinGasLimit) Right(blockHeader)
-    else Left(HeaderGasLimitError)
+
+    if (blockHeader.gasLimit > MaxGasLimit && blockHeader.number >= blockchainConfig.eip106BlockNumber)
+      Left(HeaderGasLimitError)
+    else {
+      val gasLimitDiff = (blockHeader.gasLimit - parentHeader.gasLimit).abs
+      val gasLimitDiffLimit = parentHeader.gasLimit / GasLimitBoundDivisor
+      if (gasLimitDiff < gasLimitDiffLimit && blockHeader.gasLimit >= MinGasLimit)
+        Right(blockHeader)
+      else
+        Left(HeaderGasLimitError)
+    }
   }
 
   /**

src/test/scala/io/iohk/ethereum/jsonrpc/PersonalServiceSpec.scala

@@ -345,6 +345,7 @@ class PersonalServiceSpec extends FlatSpec with Matchers with MockFactory with S
       override val homesteadBlockNumber: BigInt = 0
       override val eip150BlockNumber: BigInt = 0
       override val eip160BlockNumber: BigInt = 0
+      override val eip106BlockNumber: BigInt = 0
       override val difficultyBombPauseBlockNumber: BigInt = 0
       override val difficultyBombContinueBlockNumber: BigInt = 0
       override val customGenesisFileOpt: Option[String] = None

src/test/scala/io/iohk/ethereum/mining/BlockGeneratorSpec.scala

@@ -105,6 +105,7 @@ class BlockGeneratorSpec extends FlatSpec with Matchers with PropertyChecks with
       override val difficultyBombPauseBlockNumber: BigInt = 3000000
       override val difficultyBombContinueBlockNumber: BigInt = 5000000
       override val eip155BlockNumber: BigInt = Long.MaxValue
+      override val eip106BlockNumber: BigInt = Long.MaxValue
       override val chainId: Byte = 0x3d.toByte
       override val customGenesisFileOpt: Option[String] = Some("test-genesis.json")
       override val monetaryPolicyConfig: MonetaryPolicyConfig = MonetaryPolicyConfig(5000000, 0.2, BigInt("5000000000000000000"))
@@ -254,6 +255,7 @@ class BlockGeneratorSpec extends FlatSpec with Matchers with PropertyChecks with
       override val difficultyBombPauseBlockNumber: BigInt = 3000000
       override val difficultyBombContinueBlockNumber: BigInt = 5000000
       override val eip155BlockNumber: BigInt = 0
+      override val eip106BlockNumber: BigInt = Long.MaxValue
       override val chainId: Byte = 0x3d.toByte
       override val customGenesisFileOpt: Option[String] = Some("test-genesis.json")
       override val monetaryPolicyConfig: MonetaryPolicyConfig = MonetaryPolicyConfig(5000000, 0.2, BigInt("5000000000000000000"))

src/test/scala/io/iohk/ethereum/network/handshaker/EtcHandshakerSpec.scala

@@ -154,6 +154,7 @@ class EtcHandshakerSpec extends FlatSpec with Matchers  {
       override val eip150BlockNumber: BigInt = 0
       override val eip160BlockNumber: BigInt = 0
       override val eip155BlockNumber: BigInt = 0
+      override val eip106BlockNumber: BigInt = 0
       override val difficultyBombPauseBlockNumber: BigInt = 0
       override val difficultyBombContinueBlockNumber: BigInt = 0
       override val customGenesisFileOpt: Option[String] = None

src/test/scala/io/iohk/ethereum/validators/BlockHeaderValidatorSpec.scala

@@ -28,6 +28,7 @@ class BlockHeaderValidatorSpec extends FlatSpec with Matchers with PropertyCheck
     override val eip155BlockNumber: BigInt = Long.MaxValue
     override val eip160BlockNumber: BigInt = Long.MaxValue
     override val eip150BlockNumber: BigInt = Long.MaxValue
+    override val eip106BlockNumber: BigInt = 20
     override val chainId: Byte = 0x3d.toByte
     override val daoForkBlockHash: ByteString = ByteString("unused")
     override val monetaryPolicyConfig: MonetaryPolicyConfig = null
@@ -99,6 +100,12 @@ class BlockHeaderValidatorSpec extends FlatSpec with Matchers with PropertyCheck
     }
   }
 
+  it should "return a failure if created with gas limit above threshold and block number >= eip106 block number" in {
+    val validParent = validBlockParent.copy(gasLimit = Long.MaxValue)
+    val invalidBlockHeader = validBlockHeader.copy(gasLimit = BigInt(Long.MaxValue) + 1)
+    blockHeaderValidator.validate(invalidBlockHeader, validParent) shouldBe Left(HeaderGasLimitError)
+  }
+
   it should "return a failure if created based on invalid number" in {
     forAll(bigIntGen) { number =>
       val blockHeader = validBlockHeader.copy(number = number)

src/universal/conf/blockchain.conf

@@ -7,6 +7,10 @@ mantis {
     # Doc: https://github.com/ethereum/EIPs/blob/master/EIPS/eip-2.md
     # homestead-block-number = "1150000"
 
+    # EIP-106 fork block number
+    # Doc: https://github.com/ethereum/EIPs/issues/106
+    # eip106-block-number = "9223372036854775807"
+
     # EIP-150 fork block number
     # Doc: https://github.com/ethereum/EIPs/issues/150
     # eip150-block-number = "2500000"