add local xdpos function

add readme

changes to support xdpos2 protocol from block 0

cicd/Dockerfile

@@ -5,11 +5,14 @@ RUN apk add make build-base linux-headers
 COPY . /builder
 RUN cd /builder && make && mv /builder/build/bin/XDC /builder/build/bin/XDC-mainnet
 
+RUN mv /builder/common/constants/constants.go.testnet /builder/common/constants.go
+RUN cd /builder && make && mv /builder/build/bin/XDC /builder/build/bin/XDC-testnet
+
 RUN mv /builder/common/constants/constants.go.devnet /builder/common/constants.go
 RUN cd /builder && make && mv /builder/build/bin/XDC /builder/build/bin/XDC-devnet
 
-RUN mv /builder/common/constants/constants.go.testnet /builder/common/constants.go
-RUN cd /builder && make && mv /builder/build/bin/XDC /builder/build/bin/XDC-testnet
+RUN mv /builder/common/constants/constants.go.local /builder/common/constants.go
+RUN cd /builder && make && mv /builder/build/bin/XDC /builder/build/bin/XDC-local
 
 # The runtime image
 FROM alpine:3
@@ -18,11 +21,13 @@ WORKDIR /work
 
 RUN apk add --no-cache bash curl
 
+COPY --from=builder /builder/build/bin/XDC-local /usr/bin
 COPY --from=builder /builder/build/bin/XDC-devnet /usr/bin
 COPY --from=builder /builder/build/bin/XDC-testnet /usr/bin
 COPY --from=builder /builder/build/bin/XDC-mainnet /usr/bin
 
 # # Copy over files
+ADD cicd/local /work/local
 ADD cicd/devnet /work/devnet
 ADD cicd/testnet /work/testnet
 ADD cicd/mainnet /work/mainnet

cicd/entry.sh

@@ -1,7 +1,7 @@
 #!/bin/bash
 if test -z "$NETWORK"
 then
-    echo "NETWORK env Must be set, mainnet/testnet/devnet"
+    echo "NETWORK env Must be set, mainnet/testnet/devnet/local"
     exit 1
 fi
 

cicd/local/README.md

@@ -0,0 +1,10 @@
+To set up local xdpos you need pass env NETWORK=local and inject 2 files when starting the container
+1. genesis.json - deploy to path "/work/genesis.json" in the container. 
+   - Creating genesis.json using puppeth
+     1. "make puppeth" from base repo directory 
+     2. run the binary (genesis wizard) "./build/bin/puppeth"
+     3. the output genesis.json will be in your ~/.puppeth directory
+
+2. bootnodes.list - deploy to path "/work/bootnodes.list" in the container.
+    - check example bootnode format in cicd/devnet or cicd/testnet 
+    - REQUIRES newline at the end of the file, or the last line won't read

cicd/local/start.sh

@@ -0,0 +1,83 @@
+#!/bin/bash
+if [ ! -d /work/xdcchain/XDC/chaindata ]
+then
+  if test -z "$PRIVATE_KEY"
+  then
+        echo "PRIVATE_KEY environment variable has not been set."
+        exit 1
+  fi
+  echo $PRIVATE_KEY >> /tmp/key
+  wallet=$(XDC account import --password .pwd --datadir /work/xdcchain /tmp/key | awk -F '[{}]' '{print $2}')
+  XDC --datadir /work/xdcchain init /work/genesis.json
+else
+  wallet=$(XDC account list --datadir /work/xdcchain | head -n 1 | awk -F '[{}]' '{print $2}')
+fi
+
+input="/work/bootnodes.list"
+bootnodes=""
+while IFS= read -r line
+do
+    if [ -z "${bootnodes}" ]
+    then
+        bootnodes=$line
+    else
+        bootnodes="${bootnodes},$line"
+    fi
+done < "$input"
+
+log_level=3
+if test -z "$LOG_LEVEL"
+then
+  echo "Log level not set, default to verbosity of $log_level"
+else
+  echo "Log level found, set to $LOG_LEVEL"
+  log_level=$LOG_LEVEL
+fi
+
+port=30303
+if test -z "$PORT"
+then
+  echo "PORT not set, default to $port"
+else
+  echo "PORT found, set to $PORT"
+  port=$PORT
+fi
+
+rpc_port=8545
+if test -z "$RPC_PORT"
+then
+  echo "RPC_PORT not set, default to $rpc_port"
+else
+  echo "RPC_PORT found, set to $RPC_PORT"
+  rpc_port=$RPC_PORT
+fi
+
+ws_port=8555
+if test -z "$WS_PORT"
+then
+  echo "WS_PORT not set, default to  $ws_port"
+else
+  echo "WS_PORT found, set to $WS_PORT"
+  ws_port=$WS_PORT
+fi
+
+netstats="${NODE_NAME}-${wallet}:xinfin_xdpos_hybrid_network_stats@devnetstats.apothem.network:2000"
+
+
+echo "Running a node with wallet: ${wallet}"
+echo "Starting nodes with $bootnodes ..."
+
+# Note: --gcmode=archive means node will store all historical data. This will lead to high memory usage. But sync mode require archive to sync
+# https://github.com/XinFinOrg/XDPoSChain/issues/268
+
+XDC --ethstats ${netstats} --gcmode archive \
+--bootnodes ${bootnodes} --syncmode full \
+--datadir /work/xdcchain --networkid 551 \
+-port $port --rpc --rpccorsdomain "*" --rpcaddr 0.0.0.0 \
+--rpcport $rpc_port \
+--rpcapi db,eth,debug,net,shh,txpool,personal,web3,XDPoS \
+--rpcvhosts "*" --unlock "${wallet}" --password /work/.pwd --mine \
+--gasprice "1" --targetgaslimit "420000000" --verbosity ${log_level} \
+--debugdatadir /work/xdcchain \
+--ws --wsaddr=0.0.0.0 --wsport $ws_port \
+--wsorigins "*" 2>&1 >>/work/xdcchain/xdc.log | tee -a /work/xdcchain/xdc.log

cmd/puppeth/wizard_genesis.go

@@ -51,11 +51,11 @@ func (w *wizard) makeGenesis() {
 		Difficulty: big.NewInt(524288),
 		Alloc:      make(core.GenesisAlloc),
 		Config: &params.ChainConfig{
-			HomesteadBlock: big.NewInt(1),
-			EIP150Block:    big.NewInt(2),
-			EIP155Block:    big.NewInt(3),
-			EIP158Block:    big.NewInt(3),
-			ByzantiumBlock: big.NewInt(4),
+			HomesteadBlock: big.NewInt(0),
+			EIP150Block:    big.NewInt(0),
+			EIP155Block:    big.NewInt(0),
+			EIP158Block:    big.NewInt(0),
+			ByzantiumBlock: big.NewInt(0),
 		},
 	}
 	// Figure out which consensus engine to choose
@@ -147,7 +147,7 @@ func (w *wizard) makeGenesis() {
 		fmt.Println()
 		fmt.Printf("Proportion of total masternodes v2 vote collection to generate a QC (float value), should be two thirds of masternodes? (default = %f)\n", 0.667)
 		genesis.Config.XDPoS.V2.CurrentConfig.CertThreshold = w.readDefaultFloat(0.667)
-
+		genesis.Config.XDPoS.V2.CurrentConfig.MaxMasternodes = 108
 		genesis.Config.XDPoS.V2.AllConfigs[0] = genesis.Config.XDPoS.V2.CurrentConfig
 
 		fmt.Println()

common/constants/constants.go.local

@@ -0,0 +1,158 @@
+package common
+
+import (
+	"math/big"
+)
+
+const (
+	RewardMasterPercent        = 90
+	RewardVoterPercent         = 0
+	RewardFoundationPercent    = 10
+	HexSignMethod              = "e341eaa4"
+	HexSetSecret               = "34d38600"
+	HexSetOpening              = "e11f5ba2"
+	EpocBlockSecret            = 800
+	EpocBlockOpening           = 850
+	EpocBlockRandomize         = 900
+	MaxMasternodes             = 18
+	MaxMasternodesV2           = 108 // Last v1 masternodes
+	LimitPenaltyEpoch          = 4
+	LimitPenaltyEpochV2        = 0
+	BlocksPerYearTest          = uint64(200000)
+	BlocksPerYear              = uint64(15768000)
+	LimitThresholdNonceInQueue = 10
+	DefaultMinGasPrice         = 250000000
+	MergeSignRange             = 15
+	RangeReturnSigner          = 150
+	MinimunMinerBlockPerEpoch  = 1
+
+	OneYear                    = uint64(365 * 86400)
+	LiquidateLendingTradeBlock = uint64(100)
+)
+
+var Rewound = uint64(0)
+
+var TIP2019Block = big.NewInt(0)
+var TIPSigning = big.NewInt(0)
+var TIPRandomize = big.NewInt(0)
+
+var TIPV2SwitchBlock = big.NewInt(0)
+
+var TIPIncreaseMasternodes = big.NewInt(0) // Upgrade MN Count at Block.
+var TIPNoHalvingMNReward = big.NewInt(0)   // hardfork no halving masternodes reward
+var BlackListHFNumber = uint64(0)
+var TIPXDCX = big.NewInt(0)
+var TIPXDCXLending = big.NewInt(0)
+var TIPXDCXCancellationFee = big.NewInt(0)
+var TIPXDCXCancellationFeeTestnet = big.NewInt(0)
+var TIPXDCXMinerDisable = big.NewInt(0)
+var TIPXDCXReceiverDisable = big.NewInt(0)
+var BerlinBlock = big.NewInt(0)
+var LondonBlock = big.NewInt(0)
+var MergeBlock = big.NewInt(0)
+var ShanghaiBlock = big.NewInt(0)
+var Eip1559Block = big.NewInt(9999999999)
+
+var TIPXDCXTestnet = big.NewInt(0)
+var IsTestnet bool = false
+var Enable0xPrefix bool = true
+var StoreRewardFolder string
+var RollbackHash Hash
+var BasePrice = big.NewInt(1000000000000000000)                       // 1
+var RelayerLockedFund = big.NewInt(20000)                             // 20000 XDC
+var RelayerFee = big.NewInt(1000000000000000)                         // 0.001
+var XDCXBaseFee = big.NewInt(10000)                                   // 1 / XDCXBaseFee
+var RelayerCancelFee = big.NewInt(100000000000000)                    // 0.0001
+var XDCXBaseCancelFee = new(big.Int).Mul(XDCXBaseFee, big.NewInt(10)) // 1/ (XDCXBaseFee *10)
+var RelayerLendingFee = big.NewInt(10000000000000000)                 // 0.01
+var RelayerLendingCancelFee = big.NewInt(1000000000000000)            // 0.001
+var BaseLendingInterest = big.NewInt(100000000)                       // 1e8
+
+var MinGasPrice = big.NewInt(DefaultMinGasPrice)
+var RelayerRegistrationSMC = "0x16c63b79f9C8784168103C0b74E6A59EC2de4a02"
+var RelayerRegistrationSMCTestnet = "0xA1996F69f47ba14Cb7f661010A7C31974277958c"
+var LendingRegistrationSMC = "0x7d761afd7ff65a79e4173897594a194e3c506e57"
+var LendingRegistrationSMCTestnet = "0x28d7fC2Cf5c18203aaCD7459EFC6Af0643C97bE8"
+var TRC21IssuerSMCTestNet = HexToAddress("0x0E2C88753131CE01c7551B726b28BFD04e44003F")
+var TRC21IssuerSMC = HexToAddress("0x8c0faeb5C6bEd2129b8674F262Fd45c4e9468bee")
+var XDCXListingSMC = HexToAddress("0xDE34dD0f536170993E8CFF639DdFfCF1A85D3E53")
+var XDCXListingSMCTestNet = HexToAddress("0x14B2Bf043b9c31827A472CE4F94294fE9a6277e0")
+var TRC21GasPriceBefore = big.NewInt(2500)
+var TRC21GasPrice = big.NewInt(250000000)
+var RateTopUp = big.NewInt(90) // 90%
+var BaseTopUp = big.NewInt(100)
+var BaseRecall = big.NewInt(100)
+var TIPTRC21Fee = big.NewInt(13523400)
+var TIPTRC21FeeTestnet = big.NewInt(225000)
+var BlockNumberGas50x = big.NewInt(11818181)
+var LimitTimeFinality = uint64(30) // limit in 30 block
+
+var IgnoreSignerCheckBlockArray = map[uint64]bool{
+	uint64(1032300):  true,
+	uint64(1033200):  true,
+	uint64(27307800): true,
+	uint64(28270800): true,
+}
+var Blacklist = map[Address]bool{
+	HexToAddress("0x5248bfb72fd4f234e062d3e9bb76f08643004fcd"): true,
+	HexToAddress("0x5ac26105b35ea8935be382863a70281ec7a985e9"): true,
+	HexToAddress("0x09c4f991a41e7ca0645d7dfbfee160b55e562ea4"): true,
+	HexToAddress("0xb3157bbc5b401a45d6f60b106728bb82ebaa585b"): true,
+	HexToAddress("0x741277a8952128d5c2ffe0550f5001e4c8247674"): true,
+	HexToAddress("0x10ba49c1caa97d74b22b3e74493032b180cebe01"): true,
+	HexToAddress("0x07048d51d9e6179578a6e3b9ee28cdc183b865e4"): true,
+	HexToAddress("0x4b899001d73c7b4ec404a771d37d9be13b8983de"): true,
+	HexToAddress("0x85cb320a9007f26b7652c19a2a65db1da2d0016f"): true,
+	HexToAddress("0x06869dbd0e3a2ea37ddef832e20fa005c6f0ca39"): true,
+	HexToAddress("0x82e48bc7e2c93d89125428578fb405947764ad7c"): true,
+	HexToAddress("0x1f9a78534d61732367cbb43fc6c89266af67c989"): true,
+	HexToAddress("0x7c3b1fa91df55ff7af0cad9e0399384dc5c6641b"): true,
+	HexToAddress("0x5888dc1ceb0ff632713486b9418e59743af0fd20"): true,
+	HexToAddress("0xa512fa1c735fc3cc635624d591dd9ea1ce339ca5"): true,
+	HexToAddress("0x0832517654c7b7e36b1ef45d76de70326b09e2c7"): true,
+	HexToAddress("0xca14e3c4c78bafb60819a78ff6e6f0f709d2aea7"): true,
+	HexToAddress("0x652ce195a23035114849f7642b0e06647d13e57a"): true,
+	HexToAddress("0x29a79f00f16900999d61b6e171e44596af4fb5ae"): true,
+	HexToAddress("0xf9fd1c2b0af0d91b0b6754e55639e3f8478dd04a"): true,
+	HexToAddress("0xb835710c9901d5fe940ef1b99ed918902e293e35"): true,
+	HexToAddress("0x04dd29ce5c253377a9a3796103ea0d9a9e514153"): true,
+	HexToAddress("0x2b4b56846eaf05c1fd762b5e1ac802efd0ab871c"): true,
+	HexToAddress("0x1d1f909f6600b23ce05004f5500ab98564717996"): true,
+	HexToAddress("0x0dfdcebf80006dc9ab7aae8c216b51c6b6759e86"): true,
+	HexToAddress("0x2b373890a28e5e46197fbc04f303bbfdd344056f"): true,
+	HexToAddress("0xa8a3ef3dc5d8e36aee76f3671ec501ec31e28254"): true,
+	HexToAddress("0x4f3d18136fe2b5665c29bdaf74591fc6625ef427"): true,
+	HexToAddress("0x175d728b0e0f1facb5822a2e0c03bde93596e324"): true,
+	HexToAddress("0xd575c2611984fcd79513b80ab94f59dc5bab4916"): true,
+	HexToAddress("0x0579337873c97c4ba051310236ea847f5be41bc0"): true,
+	HexToAddress("0xed12a519cc15b286920fc15fd86106b3e6a16218"): true,
+	HexToAddress("0x492d26d852a0a0a2982bb40ec86fe394488c419e"): true,
+	HexToAddress("0xce5c7635d02dc4e1d6b46c256cae6323be294a32"): true,
+	HexToAddress("0x8b94db158b5e78a6c032c7e7c9423dec62c8b11c"): true,
+	HexToAddress("0x0e7c48c085b6b0aa7ca6e4cbcc8b9a92dc270eb4"): true,
+	HexToAddress("0x206e6508462033ef8425edc6c10789d241d49acb"): true,
+	HexToAddress("0x7710e7b7682f26cb5a1202e1cff094fbf7777758"): true,
+	HexToAddress("0xcb06f949313b46bbf53b8e6b2868a0c260ff9385"): true,
+	HexToAddress("0xf884e43533f61dc2997c0e19a6eff33481920c00"): true,
+	HexToAddress("0x8b635ef2e4c8fe21fc2bda027eb5f371d6aa2fc1"): true,
+	HexToAddress("0x10f01a27cf9b29d02ce53497312b96037357a361"): true,
+	HexToAddress("0x693dd49b0ed70f162d733cf20b6c43dc2a2b4d95"): true,
+	HexToAddress("0xe0bec72d1c2a7a7fb0532cdfac44ebab9f6f41ee"): true,
+	HexToAddress("0xc8793633a537938cb49cdbbffd45428f10e45b64"): true,
+	HexToAddress("0x0d07a6cbbe9fa5c4f154e5623bfe47fb4d857d8e"): true,
+	HexToAddress("0xd4080b289da95f70a586610c38268d8d4cf1e4c4"): true,
+	HexToAddress("0x8bcfb0caf41f0aa1b548cae76dcdd02e33866a1b"): true,
+	HexToAddress("0xabfef22b92366d3074676e77ea911ccaabfb64c1"): true,
+	HexToAddress("0xcc4df7a32faf3efba32c9688def5ccf9fefe443d"): true,
+	HexToAddress("0x7ec1e48a582475f5f2b7448a86c4ea7a26ea36f8"): true,
+	HexToAddress("0xe3de67289080f63b0c2612844256a25bb99ac0ad"): true,
+	HexToAddress("0x3ba623300cf9e48729039b3c9e0dee9b785d636e"): true,
+	HexToAddress("0x402f2cfc9c8942f5e7a12c70c625d07a5d52fe29"): true,
+	HexToAddress("0xd62358d42afbde095a4ca868581d85f9adcc3d61"): true,
+	HexToAddress("0x3969f86acb733526cd61e3c6e3b4660589f32bc6"): true,
+	HexToAddress("0x67615413d7cdadb2c435a946aec713a9a9794d39"): true,
+	HexToAddress("0xfe685f43acc62f92ab01a8da80d76455d39d3cb3"): true,
+	HexToAddress("0x3538a544021c07869c16b764424c5987409cba48"): true,
+	HexToAddress("0xe187cf86c2274b1f16e8225a7da9a75aba4f1f5f"): true,
+	HexToAddress("0x0000000000000000000000000000000000000011"): true,
+}

consensus/XDPoS/engines/engine_v2/engine.go

@@ -191,7 +191,10 @@ func (x *XDPoS_v2) initial(chain consensus.ChainReader, header *types.Header) er
 			Signatures:        nil,
 			GapNumber:         header.Number.Uint64() - x.config.Gap,
 		}
-
+		// prevent overflow
+		if header.Number.Uint64() < x.config.Gap {
+			quorumCert.GapNumber = 0
+		}
 		// can not call processQC because round is equal to default
 		x.currentRound = 1
 		x.highestQuorumCert = quorumCert
@@ -210,6 +213,10 @@ func (x *XDPoS_v2) initial(chain consensus.ChainReader, header *types.Header) er
 
 	// Initial first v2 snapshot
 	lastGapNum := x.config.V2.SwitchBlock.Uint64() - x.config.Gap
+	// prevent overflow
+	if x.config.V2.SwitchBlock.Uint64() < x.config.Gap {
+		lastGapNum = 0
+	}
 	lastGapHeader := chain.GetHeaderByNumber(lastGapNum)
 
 	snap, _ := loadSnapshot(x.db, lastGapHeader.Hash())
@@ -846,6 +853,10 @@ func (x *XDPoS_v2) verifyQC(blockChainReader consensus.ChainReader, quorumCert *
 	}
 	epochSwitchNumber := epochInfo.EpochSwitchBlockInfo.Number.Uint64()
 	gapNumber := epochSwitchNumber - epochSwitchNumber%x.config.Epoch - x.config.Gap
+	// prevent overflow
+	if epochSwitchNumber-epochSwitchNumber%x.config.Epoch < x.config.Gap {
+		gapNumber = 0
+	}
 	if gapNumber != quorumCert.GapNumber {
 		log.Error("[verifyQC] QC gap number mismatch", "epochSwitchNumber", epochSwitchNumber, "BlockNum", quorumCert.ProposedBlockInfo.Number, "BlockInfoHash", quorumCert.ProposedBlockInfo.Hash, "Gap", quorumCert.GapNumber, "GapShouldBe", gapNumber)
 		return fmt.Errorf("gap number mismatch QC Gap %d, shouldBe %d", quorumCert.GapNumber, gapNumber)

consensus/XDPoS/engines/engine_v2/epochSwitch.go

@@ -49,6 +49,26 @@ func (x *XDPoS_v2) getEpochSwitchInfo(chain consensus.ChainReader, header *types
 	}
 	if isEpochSwitch {
 		log.Debug("[getEpochSwitchInfo] header is epoch switch", "hash", hash.Hex(), "number", h.Number.Uint64())
+		if h.Number.Uint64() == 0 {
+			log.Warn("[getEpochSwitchInfo] block 0, init epoch differently")
+			// handle genesis block differently as follows
+			masternodes := common.ExtractAddressFromBytes(h.Extra[32 : len(h.Extra)-65])
+			penalties := []common.Address{}
+			standbynodes := []common.Address{}
+			epochSwitchInfo := &types.EpochSwitchInfo{
+				Penalties:      penalties,
+				Standbynodes:   standbynodes,
+				Masternodes:    masternodes,
+				MasternodesLen: len(masternodes),
+				EpochSwitchBlockInfo: &types.BlockInfo{
+					Hash:   hash,
+					Number: h.Number,
+					Round:  0,
+				},
+			}
+			x.epochSwitches.Add(hash, epochSwitchInfo)
+			return epochSwitchInfo, nil
+		}
 		quorumCert, round, masternodes, err := x.getExtraFields(h)
 		if err != nil {
 			log.Error("[getEpochSwitchInfo] get extra field", "err", err, "number", h.Number.Uint64())

consensus/XDPoS/engines/engine_v2/snapshot.go

@@ -78,6 +78,10 @@ func (x *XDPoS_v2) getSnapshot(chain consensus.ChainReader, number uint64, isGap
 		gapBlockNum = number
 	} else {
 		gapBlockNum = number - number%x.config.Epoch - x.config.Gap
+		//prevent overflow
+		if number-number%x.config.Epoch < x.config.Gap {
+			gapBlockNum = 0
+		}
 	}
 
 	gapBlockHash := chain.GetHeaderByNumber(gapBlockNum).Hash()

consensus/XDPoS/engines/engine_v2/timeout.go

@@ -231,6 +231,10 @@ func (x *XDPoS_v2) sendTimeout(chain consensus.ChainReader) error {
 		// Notice this +1 is because we expect a block whos is the child of currentHeader
 		currentNumber := currentBlockHeader.Number.Uint64() + 1
 		gapNumber = currentNumber - currentNumber%x.config.Epoch - x.config.Gap
+		// prevent overflow
+		if currentNumber-currentNumber%x.config.Epoch < x.config.Gap {
+			gapNumber = 0
+		}
 		log.Debug("[sendTimeout] is epoch switch when sending out timeout message", "currentNumber", currentNumber, "gapNumber", gapNumber)
 	} else {
 		epochSwitchInfo, err := x.getEpochSwitchInfo(chain, currentBlockHeader, currentBlockHeader.Hash())
@@ -239,6 +243,10 @@ func (x *XDPoS_v2) sendTimeout(chain consensus.ChainReader) error {
 			return err
 		}
 		gapNumber = epochSwitchInfo.EpochSwitchBlockInfo.Number.Uint64() - epochSwitchInfo.EpochSwitchBlockInfo.Number.Uint64()%x.config.Epoch - x.config.Gap
+		// prevent overflow
+		if epochSwitchInfo.EpochSwitchBlockInfo.Number.Uint64()-epochSwitchInfo.EpochSwitchBlockInfo.Number.Uint64()%x.config.Epoch < x.config.Gap {
+			gapNumber = 0
+		}
 		log.Debug("[sendTimeout] non-epoch-switch block found its epoch block and calculated the gapNumber", "epochSwitchInfo.EpochSwitchBlockInfo.Number", epochSwitchInfo.EpochSwitchBlockInfo.Number.Uint64(), "gapNumber", gapNumber)
 	}
 

consensus/XDPoS/engines/engine_v2/vote.go

@@ -30,6 +30,10 @@ func (x *XDPoS_v2) sendVote(chainReader consensus.ChainReader, blockInfo *types.
 	}
 	epochSwitchNumber := epochSwitchInfo.EpochSwitchBlockInfo.Number.Uint64()
 	gapNumber := epochSwitchNumber - epochSwitchNumber%x.config.Epoch - x.config.Gap
+	// prevent overflow
+	if epochSwitchNumber-epochSwitchNumber%x.config.Epoch < x.config.Gap {
+		gapNumber = 0
+	}
 	signedHash, err := x.signSignature(types.VoteSigHash(&types.VoteForSign{
 		ProposedBlockInfo: blockInfo,
 		GapNumber:         gapNumber,

eth/hooks/engine_v2_hooks.go

@@ -222,6 +222,11 @@ func GetSigningTxCount(c *XDPoS.XDPoS, chain consensus.ChainReader, header *type
 	signers := make(map[common.Address]*contracts.RewardLog)
 	mapBlkHash := map[uint64]common.Hash{}
 
+	// prevent overflow
+	if number == 0 {
+		return signers, nil
+	}
+
 	data := make(map[common.Hash][]common.Address)
 	epochCount := 0
 	var masternodes []common.Address
@@ -256,6 +261,10 @@ func GetSigningTxCount(c *XDPoS.XDPoS, chain consensus.ChainReader, header *type
 			from := *tx.From()
 			data[blkHash] = append(data[blkHash], from)
 		}
+		// prevent overflow
+		if i == 0 {
+			return signers, nil
+		}
 	}
 
 	for i := startBlockNumber; i <= endBlockNumber; i++ {