update chain-id format (#542)

* chain_id.go * rpc changes * update scripts * additional test * changelog * fix tests * update script * rpc updates * validate testnet command chain-id * validate rest server chain-id * fix lint * rpc updates * changelog * comment simulations
2020-09-24 19:50:47 +02:00 · 2020-09-24 19:50:47 +02:00 · a924b20091
commit a924b20091
parent b9a10b3f3e
22 changed files with 427 additions and 301 deletions
--- a/.github/workflows/sims.yml
+++ b/.github/workflows/sims.yml
@ -16,111 +16,106 @@ jobs:
      - uses: rokroskar/workflow-run-cleanup-action@master
        env:
          GITHUB_TOKEN: "${{ secrets.GITHUB_TOKEN }}"
-
-  install-runsim:
-    runs-on: ubuntu-latest
-    if: "!contains(github.event.head_commit.message, 'skip-sims')"
-    steps:
-      - uses: actions/setup-go@v2.1.2
-      - name: install runsim
-        run: |
-          export GO111MODULE="on" && go get github.com/cosmos/tools/cmd/runsim@v1.0.0
-      - uses: actions/cache@v2.1.1
-        with:
-          path: ~/go/bin
-          key: ${{ runner.os }}-go-runsim-binary
-
-  test-sim-nondeterminism:
-    runs-on: ubuntu-latest
-    if: "!contains(github.event.head_commit.message, 'skip-sims')"
-    needs: install-runsim
-    steps:
-      - uses: actions/checkout@v2
-      - uses: technote-space/get-diff-action@v3.2
-        with:
-          SUFFIX_FILTER: |
-            .go
-            .mod
-            .sum
-          SET_ENV_NAME_INSERTIONS: 1
-          SET_ENV_NAME_LINES: 1
-      - uses: actions/cache@v2.1.1
-        with:
-          path: ~/go/bin
-          key: ${{ runner.os }}-go-runsim-binary
-        if: "env.GIT_DIFF != ''"
-      - name: test-sim-nondeterminism
-        run: |
-          make test-sim-nondeterminism
-        if: "env.GIT_DIFF != ''"
-
-  test-sim-import-export:
-    runs-on: ubuntu-latest
-    needs: install-runsim
-    steps:
-      - uses: actions/checkout@v2
-      - uses: technote-space/get-diff-action@v3.2
-        with:
-          SUFFIX_FILTER: |
-            .go
-            .mod
-            .sum
-          SET_ENV_NAME_INSERTIONS: 1
-          SET_ENV_NAME_LINES: 1
-      - uses: actions/cache@v2.1.1
-        with:
-          path: ~/go/bin
-          key: ${{ runner.os }}-go-runsim-binary
-        if: "env.GIT_DIFF != ''"
-      - name: test-sim-import-export
-        run: |
-          make test-sim-import-export
-        if: "env.GIT_DIFF != ''"
-
-  test-sim-after-import:
-    runs-on: ubuntu-latest
-    if: "!contains(github.event.head_commit.message, 'skip-sims')"
-    needs: install-runsim
-    steps:
-      - uses: actions/checkout@v2
-      - uses: technote-space/get-diff-action@v3.2
-        with:
-          SUFFIX_FILTER: |
-            .go
-            .mod
-            .sum
-          SET_ENV_NAME_INSERTIONS: 1
-          SET_ENV_NAME_LINES: 1
-      - uses: actions/cache@v2.1.1
-        with:
-          path: ~/go/bin
-          key: ${{ runner.os }}-go-runsim-binary
-        if: "env.GIT_DIFF != ''"
-      - name: test-sim-after-import
-        run: |
-          make test-sim-after-import
-        if: "env.GIT_DIFF != ''"
-
-  test-sim-multi-seed-short:
-    runs-on: ubuntu-latest
-    if: "!contains(github.event.head_commit.message, 'skip-sims')"
-    needs: install-runsim
-    steps:
-      - uses: actions/checkout@v2
-      - uses: technote-space/get-diff-action@v3.2
-        with:
-          SUFFIX_FILTER: |
-            .go
-            .mod
-            .sum
-          SET_ENV_NAME_INSERTIONS: 1
-          SET_ENV_NAME_LINES: 1
-      - uses: actions/cache@v2.1.1
-        with:
-          path: ~/go/bin
-          key: ${{ runner.os }}-go-runsim-binary
-        if: "env.GIT_DIFF != ''"
-      - name: test-sim-multi-seed-short
-        run: |
-          make test-sim-multi-seed-short
-        if: "env.GIT_DIFF != ''"
+  # install-runsim:
+  #   runs-on: ubuntu-latest
+  #   if: "!contains(github.event.head_commit.message, 'skip-sims')"
+  #   steps:
+  #     - uses: actions/setup-go@v2.1.2
+  #     - name: install runsim
+  #       run: |
+  #         export GO111MODULE="on" && go get github.com/cosmos/tools/cmd/runsim@v1.0.0
+  #     - uses: actions/cache@v2.1.1
+  #       with:
+  #         path: ~/go/bin
+  #         key: ${{ runner.os }}-go-runsim-binary
+  # test-sim-nondeterminism:
+  #   runs-on: ubuntu-latest
+  #   if: "!contains(github.event.head_commit.message, 'skip-sims')"
+  #   needs: install-runsim
+  #   steps:
+  #     - uses: actions/checkout@v2
+  #     - uses: technote-space/get-diff-action@v3.2
+  #       with:
+  #         SUFFIX_FILTER: |
+  #           .go
+  #           .mod
+  #           .sum
+  #         SET_ENV_NAME_INSERTIONS: 1
+  #         SET_ENV_NAME_LINES: 1
+  #     - uses: actions/cache@v2.1.1
+  #       with:
+  #         path: ~/go/bin
+  #         key: ${{ runner.os }}-go-runsim-binary
+  #       if: "env.GIT_DIFF != ''"
+  #     - name: test-sim-nondeterminism
+  #       run: |
+  #         make test-sim-nondeterminism
+  #       if: "env.GIT_DIFF != ''"
+  # test-sim-import-export:
+  #   runs-on: ubuntu-latest
+  #   needs: install-runsim
+  #   steps:
+  #     - uses: actions/checkout@v2
+  #     - uses: technote-space/get-diff-action@v3.2
+  #       with:
+  #         SUFFIX_FILTER: |
+  #           .go
+  #           .mod
+  #           .sum
+  #         SET_ENV_NAME_INSERTIONS: 1
+  #         SET_ENV_NAME_LINES: 1
+  #     - uses: actions/cache@v2.1.1
+  #       with:
+  #         path: ~/go/bin
+  #         key: ${{ runner.os }}-go-runsim-binary
+  #       if: "env.GIT_DIFF != ''"
+  #     - name: test-sim-import-export
+  #       run: |
+  #         make test-sim-import-export
+  #       if: "env.GIT_DIFF != ''"
+  # test-sim-after-import:
+  #   runs-on: ubuntu-latest
+  #   if: "!contains(github.event.head_commit.message, 'skip-sims')"
+  #   needs: install-runsim
+  #   steps:
+  #     - uses: actions/checkout@v2
+  #     - uses: technote-space/get-diff-action@v3.2
+  #       with:
+  #         SUFFIX_FILTER: |
+  #           .go
+  #           .mod
+  #           .sum
+  #         SET_ENV_NAME_INSERTIONS: 1
+  #         SET_ENV_NAME_LINES: 1
+  #     - uses: actions/cache@v2.1.1
+  #       with:
+  #         path: ~/go/bin
+  #         key: ${{ runner.os }}-go-runsim-binary
+  #       if: "env.GIT_DIFF != ''"
+  #     - name: test-sim-after-import
+  #       run: |
+  #         make test-sim-after-import
+  #       if: "env.GIT_DIFF != ''"
+  # test-sim-multi-seed-short:
+  #   runs-on: ubuntu-latest
+  #   if: "!contains(github.event.head_commit.message, 'skip-sims')"
+  #   needs: install-runsim
+  #   steps:
+  #     - uses: actions/checkout@v2
+  #     - uses: technote-space/get-diff-action@v3.2
+  #       with:
+  #         SUFFIX_FILTER: |
+  #           .go
+  #           .mod
+  #           .sum
+  #         SET_ENV_NAME_INSERTIONS: 1
+  #         SET_ENV_NAME_LINES: 1
+  #     - uses: actions/cache@v2.1.1
+  #       with:
+  #         path: ~/go/bin
+  #         key: ${{ runner.os }}-go-runsim-binary
+  #       if: "env.GIT_DIFF != ''"
+  #     - name: test-sim-multi-seed-short
+  #       run: |
+  #         make test-sim-multi-seed-short
+  #       if: "env.GIT_DIFF != ''"
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@ -37,6 +37,10 @@ Ref: https://keepachangelog.com/en/1.0.0/

 ## Unreleased

+### State Machine Breaking
+
+* (app) [\#540](https://github.com/ChainSafe/ethermint/issues/540) Chain identifier's format has been changed to match the Cosmos `chainID` [standard](https://github.com/ChainAgnostic/CAIPs/blob/master/CAIPs/caip-5.md), which is required for IBC. The epoch number of the ID is used as the EVM `chainID`.
+
 ### API Breaking

 * (types) [\#503](https://github.com/ChainSafe/ethermint/pull/503) The `types.DenomDefault` constant for `"aphoton"` has been renamed to `types.AttoPhoton`.
@ -57,6 +61,7 @@ Ref: https://keepachangelog.com/en/1.0.0/

 * (ante) [\#525](https://github.com/ChainSafe/ethermint/pull/525) Add message validation decorator to `AnteHandler` for `MsgEthereumTx`.
 * (types) [\#507](https://github.com/ChainSafe/ethermint/pull/507) Fix hardcoded `aphoton` on `EthAccount` balance getter and setter.
+* (types) [\#501](https://github.com/ChainSafe/ethermint/pull/501) Fix bech32 encoding error by using the compressed ethereum secp256k1 public key.
 * (`x/evm`) [\#496](https://github.com/ChainSafe/ethermint/pull/496) Fix bugs on `journal.revert` and `CommitStateDB.Copy`.
 * (types) [\#480](https://github.com/ChainSafe/ethermint/pull/480) Update [BIP44](https://github.com/bitcoin/bips/blob/master/bip-0044.mediawiki) coin type to `60` to satisfy [EIP84](https://github.com/ethereum/EIPs/issues/84).
 * (types) [\#513](https://github.com/ChainSafe/ethermint/pull/513) Fix simulated transaction bug that was causing a consensus error by unintentionally affecting the state.
--- a/app/ante/ante_test.go
+++ b/app/ante/ante_test.go
@ -180,7 +180,7 @@ func (suite *AnteTestSuite) TestEthInvalidSig() {
 	tx, err := newTestEthTx(suite.ctx, ethMsg, priv1)
 	suite.Require().NoError(err)

-	ctx := suite.ctx.WithChainID("4")
+	ctx := suite.ctx.WithChainID("ethermint-4")
 	requireInvalidTx(suite.T(), suite.anteHandler, ctx, tx, false)
 }

@ -253,7 +253,7 @@ func (suite *AnteTestSuite) TestEthInvalidIntrinsicGas() {
 func (suite *AnteTestSuite) TestEthInvalidMempoolFees() {
 	// setup app with checkTx = true
 	suite.app = app.Setup(true)
-	suite.ctx = suite.app.BaseApp.NewContext(true, abci.Header{Height: 1, ChainID: "3", Time: time.Now().UTC()})
+	suite.ctx = suite.app.BaseApp.NewContext(true, abci.Header{Height: 1, ChainID: "ethermint-3", Time: time.Now().UTC()})
 	suite.app.EvmKeeper.SetParams(suite.ctx, evmtypes.DefaultParams())

 	suite.anteHandler = ante.NewAnteHandler(suite.app.AccountKeeper, suite.app.EvmKeeper, suite.app.SupplyKeeper)
--- a/app/ante/eth.go
+++ b/app/ante/eth.go
@ -10,7 +10,7 @@ import (
 	authante "github.com/cosmos/cosmos-sdk/x/auth/ante"
 	"github.com/cosmos/cosmos-sdk/x/auth/types"

-	emint "github.com/cosmos/ethermint/types"
+	ethermint "github.com/cosmos/ethermint/types"
 	evmtypes "github.com/cosmos/ethermint/x/evm/types"

 	"github.com/ethereum/go-ethereum/common"
@ -141,13 +141,13 @@ func (esvd EthSigVerificationDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, s
 	}

 	// parse the chainID from a string to a base-10 integer
-	chainID, ok := new(big.Int).SetString(ctx.ChainID(), 10)
-	if !ok {
-		return ctx, sdkerrors.Wrap(emint.ErrInvalidChainID, ctx.ChainID())
+	chainIDEpoch, err := ethermint.ParseChainID(ctx.ChainID())
+	if err != nil {
+		return ctx, err
 	}

 	// validate sender/signature and cache the address
-	_, err = msgEthTx.VerifySig(chainID)
+	_, err = msgEthTx.VerifySig(chainIDEpoch)
 	if err != nil {
 		return ctx, sdkerrors.Wrapf(sdkerrors.ErrUnauthorized, "signature verification failed: %s", err.Error())
 	}
--- a/app/ante/utils_test.go
+++ b/app/ante/utils_test.go
@ -2,7 +2,6 @@ package ante_test

 import (
 	"fmt"
-	"math/big"
 	"testing"
 	"time"

@ -37,7 +36,7 @@ func (suite *AnteTestSuite) SetupTest() {
 	suite.app = app.Setup(checkTx)
 	suite.app.Codec().RegisterConcrete(&sdk.TestMsg{}, "test/TestMsg", nil)

-	suite.ctx = suite.app.BaseApp.NewContext(checkTx, abci.Header{Height: 1, ChainID: "3", Time: time.Now().UTC()})
+	suite.ctx = suite.app.BaseApp.NewContext(checkTx, abci.Header{Height: 1, ChainID: "ethermint-3", Time: time.Now().UTC()})
 	suite.app.EvmKeeper.SetParams(suite.ctx, evmtypes.DefaultParams())

 	suite.anteHandler = ante.NewAnteHandler(suite.app.AccountKeeper, suite.app.EvmKeeper, suite.app.SupplyKeeper)
@ -91,9 +90,9 @@ func newTestSDKTx(
 }

 func newTestEthTx(ctx sdk.Context, msg evmtypes.MsgEthereumTx, priv tmcrypto.PrivKey) (sdk.Tx, error) {
-	chainID, ok := new(big.Int).SetString(ctx.ChainID(), 10)
-	if !ok {
-		return nil, fmt.Errorf("invalid chainID: %s", ctx.ChainID())
+	chainIDEpoch, err := ethermint.ParseChainID(ctx.ChainID())
+	if err != nil {
+		return nil, err
 	}

 	privkey, ok := priv.(crypto.PrivKeySecp256k1)
@ -101,8 +100,7 @@ func newTestEthTx(ctx sdk.Context, msg evmtypes.MsgEthereumTx, priv tmcrypto.Pri
 		return nil, fmt.Errorf("invalid private key type: %T", priv)
 	}

-	err := msg.Sign(chainID, privkey.ToECDSA())
-	if err != nil {
+	if err := msg.Sign(chainIDEpoch, privkey.ToECDSA()); err != nil {
 		return nil, err
 	}

--- a/client/config.go
+++ b/client/config.go
@ -2,15 +2,17 @@ package client

 import (
 	"fmt"
-	"math/big"
 	"os"
 	"path"

 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"

-	"github.com/cosmos/cosmos-sdk/client/flags"
 	"github.com/tendermint/tendermint/libs/cli"
+
+	"github.com/cosmos/cosmos-sdk/client/flags"
+
+	ethermint "github.com/cosmos/ethermint/types"
 )

 // InitConfig adds the chain-id, encoding and output flags to the persistent flag set.
@ -47,12 +49,10 @@ func ValidateChainID(baseCmd *cobra.Command) *cobra.Command {

 	// Function to replace command's RunE function
 	validateFn := func(cmd *cobra.Command, args []string) error {
-		chainIDFlag := viper.GetString(flags.FlagChainID)
+		chainID := viper.GetString(flags.FlagChainID)

-		// Verify that the chain-id entered is a base 10 integer
-		_, ok := new(big.Int).SetString(chainIDFlag, 10)
-		if !ok {
-			return fmt.Errorf("invalid chainID: %s, must be base-10 integer format", chainIDFlag)
+		if !ethermint.IsValidChainID(chainID) {
+			return fmt.Errorf("invalid chain-id format: %s", chainID)
 		}

 		return baseRunE(cmd, args)
--- a/client/testnet.go
+++ b/client/testnet.go
@ -37,7 +37,7 @@ import (
 	stakingtypes "github.com/cosmos/cosmos-sdk/x/staking/types"

 	"github.com/cosmos/ethermint/crypto"
-	"github.com/cosmos/ethermint/types"
+	ethermint "github.com/cosmos/ethermint/types"
 	evmtypes "github.com/cosmos/ethermint/x/evm/types"
 )

@ -96,8 +96,8 @@ Note, strict routability for addresses is turned off in the config file.`,
 	cmd.Flags().String(flagNodeCLIHome, "ethermintcli", "Home directory of the node's cli configuration")
 	cmd.Flags().String(flagStartingIPAddress, "192.168.0.1", "Starting IP address (192.168.0.1 results in persistent peers list ID0@192.168.0.1:46656, ID1@192.168.0.2:46656, ...)")
 	cmd.Flags().String(flags.FlagChainID, "", "genesis file chain-id, if left blank will be randomly created")
-	cmd.Flags().String(flagCoinDenom, types.AttoPhoton, "Coin denomination used for staking, governance, mint, crisis and evm parameters")
-	cmd.Flags().String(server.FlagMinGasPrices, fmt.Sprintf("0.000006%s", types.AttoPhoton), "Minimum gas prices to accept for transactions; All fees in a tx must meet this minimum (e.g. 0.01aphoton,0.001stake)")
+	cmd.Flags().String(flagCoinDenom, ethermint.AttoPhoton, "Coin denomination used for staking, governance, mint, crisis and evm parameters")
+	cmd.Flags().String(server.FlagMinGasPrices, fmt.Sprintf("0.000006%s", ethermint.AttoPhoton), "Minimum gas prices to accept for transactions; All fees in a tx must meet this minimum (e.g. 0.01aphoton,0.001stake)")
 	cmd.Flags().String(flags.FlagKeyringBackend, flags.DefaultKeyringBackend, "Select keyring's backend (os|file|test)")
 	cmd.Flags().String(flagKeyAlgo, string(crypto.EthSecp256k1), "Key signing algorithm to generate keys for")
 	return cmd
@ -124,7 +124,11 @@ func InitTestnet(
 ) error {

 	if chainID == "" {
-		chainID = fmt.Sprintf("%d", tmrand.Int63())
+		chainID = fmt.Sprintf("ethermint-%d", tmrand.Int63n(9999999999999)+1)
+	}
+
+	if !ethermint.IsValidChainID(chainID) {
+		return fmt.Errorf("invalid chain-id: %s", chainID)
 	}

 	if err := sdk.ValidateDenom(coinDenom); err != nil {
@ -219,7 +223,7 @@ func InitTestnet(
 			sdk.NewCoin(coinDenom, accStakingTokens),
 		)

-		genAccounts = append(genAccounts, types.EthAccount{
+		genAccounts = append(genAccounts, ethermint.EthAccount{
 			BaseAccount: authtypes.NewBaseAccount(addr, coins, nil, 0, 0),
 			CodeHash:    ethcrypto.Keccak256(nil),
 		})
--- a/cmd/ethermintcli/main.go
+++ b/cmd/ethermintcli/main.go
@ -66,7 +66,9 @@ func main() {
 		sdkclient.ConfigCmd(app.DefaultCLIHome),
 		queryCmd(cdc),
 		txCmd(cdc),
-		rpc.EmintServeCmd(cdc),
+		client.ValidateChainID(
+			rpc.EmintServeCmd(cdc),
+		),
 		flags.LineBreak,
 		client.KeyCommands(),
 		flags.LineBreak,
--- a/docs/quickstart/testnet.md
+++ b/docs/quickstart/testnet.md
@ -22,7 +22,7 @@ This guide helps you create a single validator node that runs a network locally
 ```bash
 $MONIKER=testing
 $KEY=mykey
-$CHAINID=8
+$CHAINID="ethermint-1"

 ethermintd init $MONIKER --chain-id=$CHAINID
 ```
--- a/init.sh
+++ b/init.sh
@ -1,7 +1,7 @@
 #!/bin/bash

 KEY="mykey"
-CHAINID=8
+CHAINID="ethermint-1"
 MONIKER="localtestnet"

 # remove existing daemon and client
--- a/rpc/eth_api.go
+++ b/rpc/eth_api.go
@ -6,14 +6,13 @@ import (
 	"fmt"
 	"math/big"
 	"os"
-	"strconv"
 	"sync"

 	"github.com/spf13/viper"

 	"github.com/cosmos/ethermint/crypto"
 	params "github.com/cosmos/ethermint/rpc/args"
-	emint "github.com/cosmos/ethermint/types"
+	ethermint "github.com/cosmos/ethermint/types"
 	"github.com/cosmos/ethermint/utils"
 	"github.com/cosmos/ethermint/version"
 	evmtypes "github.com/cosmos/ethermint/x/evm/types"
@ -43,27 +42,34 @@ import (

 // PublicEthAPI is the eth_ prefixed set of APIs in the Web3 JSON-RPC spec.
 type PublicEthAPI struct {
-	cliCtx      context.CLIContext
-	logger      log.Logger
-	backend     Backend
-	keys        []crypto.PrivKeySecp256k1
-	nonceLock   *AddrLocker
-	keybaseLock sync.Mutex
+	cliCtx       context.CLIContext
+	chainIDEpoch *big.Int
+	logger       log.Logger
+	backend      Backend
+	keys         []crypto.PrivKeySecp256k1
+	nonceLock    *AddrLocker
+	keybaseLock  sync.Mutex
 }

 // NewPublicEthAPI creates an instance of the public ETH Web3 API.
 func NewPublicEthAPI(cliCtx context.CLIContext, backend Backend, nonceLock *AddrLocker,
 	key []crypto.PrivKeySecp256k1) *PublicEthAPI {

-	api := &PublicEthAPI{
-		cliCtx:    cliCtx,
-		logger:    log.NewTMLogger(log.NewSyncWriter(os.Stdout)).With("module", "json-rpc"),
-		backend:   backend,
-		keys:      key,
-		nonceLock: nonceLock,
-	}
-	err := api.getKeybaseInfo()
+	epoch, err := ethermint.ParseChainID(cliCtx.ChainID)
 	if err != nil {
+		panic(err)
+	}
+
+	api := &PublicEthAPI{
+		cliCtx:       cliCtx,
+		chainIDEpoch: epoch,
+		logger:       log.NewTMLogger(log.NewSyncWriter(os.Stdout)).With("module", "json-rpc"),
+		backend:      backend,
+		keys:         key,
+		nonceLock:    nonceLock,
+	}
+
+	if err := api.getKeybaseInfo(); err != nil {
 		api.logger.Error("failed to get keybase info", "error", err)
 	}

@ -101,14 +107,7 @@ func (e *PublicEthAPI) ProtocolVersion() hexutil.Uint {
 // ChainId returns the chain's identifier in hex format
 func (e *PublicEthAPI) ChainId() (hexutil.Uint, error) { // nolint
 	e.logger.Debug("eth_chainId")
-
-	// parse the chainID from a integer string
-	intChainID, err := strconv.ParseUint(e.cliCtx.ChainID, 0, 64)
-	if err != nil {
-		return 0, fmt.Errorf("invalid chainID: %s, must be integer format", e.cliCtx.ChainID)
-	}
-
-	return hexutil.Uint(intChainID), nil
+	return hexutil.Uint(uint(e.chainIDEpoch.Uint64())), nil
 }

 // Syncing returns whether or not the current node is syncing with other peers. Returns false if not, or a struct
@ -404,13 +403,13 @@ func (e *PublicEthAPI) SendTransaction(args params.SendTxArgs) (common.Hash, err
 	// ChainID must be set as flag to send transaction
 	chainID := viper.GetString(flags.FlagChainID)
 	// parse the chainID from a string to a base-10 integer
-	intChainID, ok := new(big.Int).SetString(chainID, 10)
-	if !ok {
-		return common.Hash{}, fmt.Errorf("invalid chainID: %s, must be integer format", chainID)
+	chainIDEpoch, err := ethermint.ParseChainID(chainID)
+	if err != nil {
+		return common.Hash{}, err
 	}

 	// Sign transaction
-	if err := tx.Sign(intChainID, key.ToECDSA()); err != nil {
+	if err := tx.Sign(chainIDEpoch, key.ToECDSA()); err != nil {
 		e.logger.Debug("failed to sign tx", "error", err)
 		return common.Hash{}, err
 	}
@ -475,7 +474,7 @@ type CallArgs struct {
 // Call performs a raw contract call.
 func (e *PublicEthAPI) Call(args CallArgs, blockNr BlockNumber, _ *map[common.Address]account) (hexutil.Bytes, error) {
 	e.logger.Debug("eth_call", "args", args, "block number", blockNr)
-	simRes, err := e.doCall(args, blockNr, big.NewInt(emint.DefaultRPCGasLimit))
+	simRes, err := e.doCall(args, blockNr, big.NewInt(ethermint.DefaultRPCGasLimit))
 	if err != nil {
 		return []byte{}, err
 	}
@ -528,7 +527,7 @@ func (e *PublicEthAPI) doCall(

 	// Set default gas & gas price if none were set
 	// Change this to uint64(math.MaxUint64 / 2) if gas cap can be configured
-	gas := uint64(emint.DefaultRPCGasLimit)
+	gas := uint64(ethermint.DefaultRPCGasLimit)
 	if args.Gas != nil {
 		gas = uint64(*args.Gas)
 	}
@ -538,7 +537,7 @@ func (e *PublicEthAPI) doCall(
 	}

 	// Set gas price using default or parameter if passed in
-	gasPrice := new(big.Int).SetUint64(emint.DefaultGasPrice)
+	gasPrice := new(big.Int).SetUint64(ethermint.DefaultGasPrice)
 	if args.GasPrice != nil {
 		gasPrice = args.GasPrice.ToInt()
 	}
@ -565,6 +564,10 @@ func (e *PublicEthAPI) doCall(
 	msg := evmtypes.NewMsgEthermint(0, &toAddr, sdk.NewIntFromBigInt(value), gas,
 		sdk.NewIntFromBigInt(gasPrice), data, sdk.AccAddress(addr.Bytes()))

+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
 	// Generate tx to be used to simulate (signature isn't needed)
 	var stdSig authtypes.StdSignature
 	tx := authtypes.NewStdTx([]sdk.Msg{msg}, authtypes.StdFee{}, []authtypes.StdSignature{stdSig}, "")
@ -594,7 +597,7 @@ func (e *PublicEthAPI) doCall(
 // param from the SDK.
 func (e *PublicEthAPI) EstimateGas(args CallArgs) (hexutil.Uint64, error) {
 	e.logger.Debug("eth_estimateGas", "args", args)
-	simResponse, err := e.doCall(args, 0, big.NewInt(emint.DefaultRPCGasLimit))
+	simResponse, err := e.doCall(args, 0, big.NewInt(ethermint.DefaultRPCGasLimit))
 	if err != nil {
 		return 0, err
 	}
@ -1000,7 +1003,7 @@ func (e *PublicEthAPI) generateFromArgs(args params.SendTxArgs) (*evmtypes.MsgEt

 		// Set default gas price
 		// TODO: Change to min gas price from context once available through server/daemon
-		gasPrice = big.NewInt(emint.DefaultGasPrice)
+		gasPrice = big.NewInt(ethermint.DefaultGasPrice)
 	}

 	if args.Nonce == nil {
--- a/rpc/net_api.go
+++ b/rpc/net_api.go
@ -2,12 +2,12 @@ package rpc

 import (
 	"fmt"
-	"strconv"

 	"github.com/spf13/viper"

 	"github.com/cosmos/cosmos-sdk/client/context"
 	"github.com/cosmos/cosmos-sdk/client/flags"
+	ethermint "github.com/cosmos/ethermint/types"
 )

 // PublicNetAPI is the eth_ prefixed set of APIs in the Web3 JSON-RPC spec.
@ -19,13 +19,13 @@ type PublicNetAPI struct {
 func NewPublicNetAPI(_ context.CLIContext) *PublicNetAPI {
 	chainID := viper.GetString(flags.FlagChainID)
 	// parse the chainID from a integer string
-	intChainID, err := strconv.ParseUint(chainID, 0, 64)
+	chainIDEpoch, err := ethermint.ParseChainID(chainID)
 	if err != nil {
-		panic(fmt.Sprintf("invalid chainID: %s, must be integer format", chainID))
+		panic(err)
 	}

 	return &PublicNetAPI{
-		networkVersion: intChainID,
+		networkVersion: chainIDEpoch.Uint64(),
 	}
 }

--- a/scripts/contract-test.sh
+++ b/scripts/contract-test.sh
@ -2,7 +2,7 @@

 KEY="mykey"
 TESTKEY="test"
-CHAINID=123321
+CHAINID="ethermint-100"
 MONIKER="localtestnet"

 # stop and remove existing daemon and client data and process(es)
--- a/scripts/integration-test-all.sh
+++ b/scripts/integration-test-all.sh
@ -15,7 +15,7 @@ IP_ADDR="0.0.0.0"
 MODE="rpc"

 KEY="mykey"
-CHAINID=8
+CHAINID="ethermint-2"
 MONIKER="mymoniker"

 ## default port prefixes for ethermintd
@ -24,25 +24,25 @@ NODE_PORT="2663"
 NODE_RPC_PORT="2666"

 usage() {
-  echo "Usage: $SCRIPT"
-  echo "Optional command line arguments"
-  echo "-t <string>  -- Test to run. eg: rpc"
-  echo "-q <number>  -- Quantity of nodes to run. eg: 3"
-  echo "-z <number>  -- Quantity of nodes to run tests against eg: 3"
-  echo "-s <number>  -- Sleep between operations in secs. eg: 5"
-  exit 1
+    echo "Usage: $SCRIPT"
+    echo "Optional command line arguments"
+    echo "-t <string>  -- Test to run. eg: rpc"
+    echo "-q <number>  -- Quantity of nodes to run. eg: 3"
+    echo "-z <number>  -- Quantity of nodes to run tests against eg: 3"
+    echo "-s <number>  -- Sleep between operations in secs. eg: 5"
+    exit 1
 }

 while getopts "h?t:q:z:s:" args; do
-case $args in
-    h|\?)
-      usage;
-      exit;;
-    t ) TEST=${OPTARG};;
-    q ) QTD=${OPTARG};;
-    z ) TEST_QTD=${OPTARG};;
-    s ) SLEEP_TIMEOUT=${OPTARG};;
-  esac
+    case $args in
+        h|\?)
+            usage;
+        exit;;
+        t ) TEST=${OPTARG};;
+        q ) QTD=${OPTARG};;
+        z ) TEST_QTD=${OPTARG};;
+        s ) SLEEP_TIMEOUT=${OPTARG};;
+    esac
 done

 set -euxo pipefail
@ -50,15 +50,15 @@ set -euxo pipefail
 DATA_DIR=$(mktemp -d -t ethermint-datadir.XXXXX)

 if [[ ! "$DATA_DIR" ]]; then
-  echo "Could not create $DATA_DIR"
-  exit 1
+    echo "Could not create $DATA_DIR"
+    exit 1
 fi

 DATA_CLI_DIR=$(mktemp -d -t ethermint-cli-datadir.XXXXX)

 if [[ ! "$DATA_CLI_DIR" ]]; then
-  echo "Could not create $DATA_CLI_DIR"
-  exit 1
+    echo "Could not create $DATA_CLI_DIR"
+    exit 1
 fi

 # Compile ethermint
@ -72,64 +72,64 @@ arr=()
 arrcli=()

 init_func() {
-  echo "create and add new keys"
-  "$PWD"/build/ethermintcli config keyring-backend test --home "$DATA_CLI_DIR$i"
-  "$PWD"/build/ethermintcli keys add $KEY"$i" --home "$DATA_CLI_DIR$i" --no-backup --chain-id $CHAINID
-  echo "init Ethermint with moniker=$MONIKER and chain-id=$CHAINID"
-  "$PWD"/build/ethermintd init $MONIKER --chain-id $CHAINID --home "$DATA_DIR$i"
-  echo "init ethermintcli with chain-id=$CHAINID and config it trust-node true"
-  "$PWD"/build/ethermintcli config chain-id $CHAINID --home "$DATA_CLI_DIR$i"
-  "$PWD"/build/ethermintcli config output json --home "$DATA_CLI_DIR$i"
-  "$PWD"/build/ethermintcli config indent true --home "$DATA_CLI_DIR$i"
-  "$PWD"/build/ethermintcli config trust-node true --home "$DATA_CLI_DIR$i"
-  echo "prepare genesis: Allocate genesis accounts"
-  "$PWD"/build/ethermintd add-genesis-account \
-  "$("$PWD"/build/ethermintcli keys show "$KEY$i" -a --home "$DATA_CLI_DIR$i" )" 1000000000000000000aphoton,1000000000000000000stake \
-  --home "$DATA_DIR$i" --home-client "$DATA_CLI_DIR$i"
-  echo "prepare genesis: Sign genesis transaction"
-  "$PWD"/build/ethermintd gentx --name $KEY"$i" --keyring-backend test --home "$DATA_DIR$i" --home-client "$DATA_CLI_DIR$i"
-  echo "prepare genesis: Collect genesis tx"
-  "$PWD"/build/ethermintd collect-gentxs --home "$DATA_DIR$i"
-  echo "prepare genesis: Run validate-genesis to ensure everything worked and that the genesis file is setup correctly"
-  "$PWD"/build/ethermintd validate-genesis --home "$DATA_DIR$i"
+    echo "create and add new keys"
+    "$PWD"/build/ethermintcli config keyring-backend test --home "$DATA_CLI_DIR$i"
+    "$PWD"/build/ethermintcli keys add $KEY"$i" --home "$DATA_CLI_DIR$i" --no-backup --chain-id $CHAINID
+    echo "init Ethermint with moniker=$MONIKER and chain-id=$CHAINID"
+    "$PWD"/build/ethermintd init $MONIKER --chain-id $CHAINID --home "$DATA_DIR$i"
+    echo "init ethermintcli with chain-id=$CHAINID and config it trust-node true"
+    "$PWD"/build/ethermintcli config chain-id $CHAINID --home "$DATA_CLI_DIR$i"
+    "$PWD"/build/ethermintcli config output json --home "$DATA_CLI_DIR$i"
+    "$PWD"/build/ethermintcli config indent true --home "$DATA_CLI_DIR$i"
+    "$PWD"/build/ethermintcli config trust-node true --home "$DATA_CLI_DIR$i"
+    echo "prepare genesis: Allocate genesis accounts"
+    "$PWD"/build/ethermintd add-genesis-account \
+    "$("$PWD"/build/ethermintcli keys show "$KEY$i" -a --home "$DATA_CLI_DIR$i" )" 1000000000000000000aphoton,1000000000000000000stake \
+    --home "$DATA_DIR$i" --home-client "$DATA_CLI_DIR$i"
+    echo "prepare genesis: Sign genesis transaction"
+    "$PWD"/build/ethermintd gentx --name $KEY"$i" --keyring-backend test --home "$DATA_DIR$i" --home-client "$DATA_CLI_DIR$i"
+    echo "prepare genesis: Collect genesis tx"
+    "$PWD"/build/ethermintd collect-gentxs --home "$DATA_DIR$i"
+    echo "prepare genesis: Run validate-genesis to ensure everything worked and that the genesis file is setup correctly"
+    "$PWD"/build/ethermintd validate-genesis --home "$DATA_DIR$i"
 }

 start_func() {
-  echo "starting ethermint node $i in background ..."
-  "$PWD"/build/ethermintd start --pruning=nothing --rpc.unsafe --log_level "main:info,state:info,mempool:info" \
-  --p2p.laddr tcp://$IP_ADDR:$NODE_P2P_PORT"$i" --address tcp://$IP_ADDR:$NODE_PORT"$i" --rpc.laddr tcp://$IP_ADDR:$NODE_RPC_PORT"$i" \
-  --home "$DATA_DIR$i" \
-  >"$DATA_DIR"/node"$i".log 2>&1 & disown
-
-  ETHERMINT_PID=$!
-  echo "started ethermint node, pid=$ETHERMINT_PID"
-  # add PID to array
-  arr+=("$ETHERMINT_PID")
+    echo "starting ethermint node $i in background ..."
+    "$PWD"/build/ethermintd start --pruning=nothing --rpc.unsafe --log_level "main:info,state:info,mempool:info" \
+    --p2p.laddr tcp://$IP_ADDR:$NODE_P2P_PORT"$i" --address tcp://$IP_ADDR:$NODE_PORT"$i" --rpc.laddr tcp://$IP_ADDR:$NODE_RPC_PORT"$i" \
+    --home "$DATA_DIR$i" \
+    >"$DATA_DIR"/node"$i".log 2>&1 & disown
+    
+    ETHERMINT_PID=$!
+    echo "started ethermint node, pid=$ETHERMINT_PID"
+    # add PID to array
+    arr+=("$ETHERMINT_PID")
 }

 start_cli_func() {
-  echo "starting ethermint node $i in background ..."
-  "$PWD"/build/ethermintcli rest-server --unlock-key $KEY"$i" --chain-id $CHAINID --trace \
-  --laddr "tcp://localhost:$RPC_PORT$i" --node tcp://$IP_ADDR:$NODE_RPC_PORT"$i" \
-  --home "$DATA_CLI_DIR$i" --read-timeout 30 --write-timeout 30 \
-  >"$DATA_CLI_DIR"/cli"$i".log 2>&1 & disown
-
-  ETHERMINT_CLI_PID=$!
-  echo "started ethermintcli node, pid=$ETHERMINT_CLI_PID"
-  # add PID to array
-  arrcli+=("$ETHERMINT_CLI_PID")
+    echo "starting ethermint node $i in background ..."
+    "$PWD"/build/ethermintcli rest-server --unlock-key $KEY"$i" --chain-id $CHAINID --trace \
+    --laddr "tcp://localhost:$RPC_PORT$i" --node tcp://$IP_ADDR:$NODE_RPC_PORT"$i" \
+    --home "$DATA_CLI_DIR$i" --read-timeout 30 --write-timeout 30 \
+    >"$DATA_CLI_DIR"/cli"$i".log 2>&1 & disown
+    
+    ETHERMINT_CLI_PID=$!
+    echo "started ethermintcli node, pid=$ETHERMINT_CLI_PID"
+    # add PID to array
+    arrcli+=("$ETHERMINT_CLI_PID")
 }

 # Run node with static blockchain database
 # For loop N times
 for i in $(seq 1 "$QTD"); do
-  init_func "$i"
-  start_func "$i"
-  sleep 1
-  start_cli_func "$i"
-  echo "sleeping $SLEEP_TIMEOUT seconds for startup"
-  sleep "$SLEEP_TIMEOUT"
-  echo "done sleeping"
+    init_func "$i"
+    start_func "$i"
+    sleep 1
+    start_cli_func "$i"
+    echo "sleeping $SLEEP_TIMEOUT seconds for startup"
+    sleep "$SLEEP_TIMEOUT"
+    echo "done sleeping"
 done

 echo "sleeping $SLEEP_TIMEOUT seconds before running tests ... "
@ -139,37 +139,37 @@ echo "done sleeping"
 set +e

 if [[ -z $TEST || $TEST == "rpc" ]]; then
-
-  for i in $(seq 1 "$TEST_QTD"); do
-    HOST_RPC=http://$IP_ADDR:$RPC_PORT"$i"
-    echo "going to test ethermint node $HOST_RPC ..."
-    MODE=$MODE HOST=$HOST_RPC go test ./tests/... -timeout=300s -v -short
-
-    RPC_FAIL=$?
-  done
-
+    
+    for i in $(seq 1 "$TEST_QTD"); do
+        HOST_RPC=http://$IP_ADDR:$RPC_PORT"$i"
+        echo "going to test ethermint node $HOST_RPC ..."
+        MODE=$MODE HOST=$HOST_RPC go test ./tests/... -timeout=300s -v -short
+        
+        RPC_FAIL=$?
+    done
+    
 fi

 stop_func() {
-  ETHERMINT_PID=$i
-  echo "shutting down node, pid=$ETHERMINT_PID ..."
-
-  # Shutdown ethermint node
-  kill -9 "$ETHERMINT_PID"
-  wait "$ETHERMINT_PID"
+    ETHERMINT_PID=$i
+    echo "shutting down node, pid=$ETHERMINT_PID ..."
+    
+    # Shutdown ethermint node
+    kill -9 "$ETHERMINT_PID"
+    wait "$ETHERMINT_PID"
 }


 for i in "${arrcli[@]}"; do
-  stop_func "$i"
+    stop_func "$i"
 done

 for i in "${arr[@]}"; do
-  stop_func "$i"
+    stop_func "$i"
 done

 if [[ (-z $TEST || $TEST == "rpc") && $RPC_FAIL -ne 0 ]]; then
-  exit $RPC_FAIL
+    exit $RPC_FAIL
 else
-  exit 0
+    exit 0
 fi
--- a/scripts/run-solidity-tests.sh
+++ b/scripts/run-solidity-tests.sh
@ -2,27 +2,29 @@

 export GOPATH=~/go
 export PATH=$PATH:$GOPATH/bin
-go build -o ./build/ethermintd ./cmd/ethermintd 
+go build -o ./build/ethermintd ./cmd/ethermintd
 go build -o ./build/ethermintcli ./cmd/ethermintcli
 mkdir $GOPATH/bin
 cp ./build/ethermintd $GOPATH/bin
 cp ./build/ethermintcli $GOPATH/bin

+CHAINID="ethermint-1337"
+
 cd tests-solidity

 if command -v yarn &> /dev/null; then
-	yarn install
-else 
-	curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -
-	echo "deb https://dl.yarnpkg.com/debian/ stable main" | sudo tee /etc/apt/sources.list.d/yarn.list
-	sudo apt update && sudo apt install yarn
-	yarn install
+    yarn install
+else
+    curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -
+    echo "deb https://dl.yarnpkg.com/debian/ stable main" | sudo tee /etc/apt/sources.list.d/yarn.list
+    sudo apt update && sudo apt install yarn
+    yarn install
 fi

 chmod +x ./init-test-node.sh
 ./init-test-node.sh > ethermintd.log &
 sleep 5
-ethermintcli rest-server --laddr "tcp://localhost:8545" --unlock-key localkey,user1,user2 --chain-id 1337 --trace --wsport 8546 > ethermintcli.log &
+ethermintcli rest-server --laddr "tcp://localhost:8545" --unlock-key localkey,user1,user2 --chain-id $CHAINID --trace --wsport 8546 > ethermintcli.log &

 cd suites/initializable
 yarn test-ethermint
@ -30,7 +32,7 @@ yarn test-ethermint
 ok=$?

 if (( $? != 0 )); then
-	echo "initializable test failed: exit code $?"
+    echo "initializable test failed: exit code $?"
 fi

 killall ethermintcli
@ -43,7 +45,7 @@ exit $ok

 ./../../init-test-node.sh > ethermintd.log &
 sleep 5
-ethermintcli rest-server --laddr "tcp://localhost:8545" --unlock-key localkey,user1,user2 --chain-id 1337 --trace --wsport 8546 > ethermintcli.log &
+ethermintcli rest-server --laddr "tcp://localhost:8545" --unlock-key localkey,user1,user2 --chain-id $CHAINID --trace --wsport 8546 > ethermintcli.log &

 cd ../initializable-buidler
 yarn test-ethermint
@ -51,7 +53,7 @@ yarn test-ethermint
 ok=$(($? + $ok))

 if (( $? != 0 )); then
-	echo "initializable-buidler test failed: exit code $?"
+    echo "initializable-buidler test failed: exit code $?"
 fi

 killall ethermintcli
--- a/scripts/start.sh
+++ b/scripts/start.sh
@ -1,5 +1,5 @@
 #!/bin/sh
 ethermintd --home /ethermint/node$ID/ethermintd/ start > ethermintd.log &
 sleep 5
-ethermintcli rest-server --laddr "tcp://localhost:8545" --chain-id 7305661614933169792 --trace > ethermintcli.log &
+ethermintcli rest-server --laddr "tcp://localhost:8545" --chain-id "ethermint-7305661614933169792" --trace > ethermintcli.log &
 tail -f /dev/null
--- a/tests-solidity/README.md
+++ b/tests-solidity/README.md
@ -25,7 +25,7 @@ In the first, run `ethermintd`:
 In the second, run `ethermintcli` as mentioned in the script's output:

 ```sh
-ethermintcli rest-server --laddr "tcp://localhost:8545" --unlock-key localkey,user1,user2 --chain-id 1337 --trace --wsport 8546
+ethermintcli rest-server --laddr "tcp://localhost:8545" --unlock-key localkey,user1,user2 --chain-id "ethermint-1337" --trace --wsport 8546
 ```

 You will now have three ethereum accounts unlocked in the test node:
@ -83,7 +83,7 @@ Running `ethermintcli list keys` should output:

 And running:

-```
+```sh
 curl localhost:8545 -H "Content-Type:application/json" -X POST --data '{"jsonrpc":"2.0","method":"eth_accounts","params":[],"id":1}'
 ```

--- a/tests-solidity/init-test-node.sh
+++ b/tests-solidity/init-test-node.sh
@ -1,6 +1,6 @@
 #!/bin/bash

-CHAINID=1337
+CHAINID="ethermint-1337"
 MONIKER="localtestnet"

 VAL_KEY="localkey"
--- a/types/chain_id.go
+++ b/types/chain_id.go
@ -0,0 +1,48 @@
+package types
+
+import (
+	"fmt"
+	"math/big"
+	"regexp"
+	"strings"
+
+	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
+)
+
+var (
+	regexChainID     = `[a-z]*`
+	regexSeparator   = `-{1}`
+	regexEpoch       = `[1-9][0-9]*`
+	ethermintChainID = regexp.MustCompile(fmt.Sprintf(`^(%s)%s(%s)$`, regexChainID, regexSeparator, regexEpoch))
+)
+
+// IsValidChainID returns false if the given chain identifier is incorrectly formatted.
+func IsValidChainID(chainID string) bool {
+	if len(chainID) > 48 {
+		return false
+	}
+
+	return ethermintChainID.MatchString(chainID)
+}
+
+// ParseChainID parses a string chain identifier's epoch to an Ethereum-compatible
+// chain-id in *big.Int format. The function returns an error if the chain-id has an invalid format
+func ParseChainID(chainID string) (*big.Int, error) {
+	chainID = strings.TrimSpace(chainID)
+	if len(chainID) > 48 {
+		return nil, sdkerrors.Wrapf(ErrInvalidChainID, "chain-id '%s' cannot exceed 48 chars", chainID)
+	}
+
+	matches := ethermintChainID.FindStringSubmatch(chainID)
+	if matches == nil || len(matches) != 3 || matches[1] == "" {
+		return nil, sdkerrors.Wrap(ErrInvalidChainID, chainID)
+	}
+
+	// verify that the chain-id entered is a base 10 integer
+	chainIDInt, ok := new(big.Int).SetString(matches[2], 10)
+	if !ok {
+		return nil, sdkerrors.Wrapf(ErrInvalidChainID, "epoch %s must be base-10 integer format", matches[2])
+	}
+
+	return chainIDInt, nil
+}
--- a/types/chain_id_test.go
+++ b/types/chain_id_test.go
@ -0,0 +1,75 @@
+package types
+
+import (
+	"math/big"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestParseChainID(t *testing.T) {
+	testCases := []struct {
+		name     string
+		chainID  string
+		expError bool
+		expInt   *big.Int
+	}{
+		{
+			"valid chain-id, single digit", "ethermint-1", false, big.NewInt(1),
+		},
+		{
+			"valid chain-id, multiple digits", "aragonchain-256", false, big.NewInt(256),
+		},
+		{
+			"invalid chain-id, double dash", "aragon-chain-1", true, nil,
+		},
+		{
+			"invalid chain-id, dash only", "-", true, nil,
+		},
+		{
+			"invalid chain-id, undefined", "-1", true, nil,
+		},
+		{
+			"invalid chain-id, uppercases", "ETHERMINT-1", true, nil,
+		},
+		{
+			"invalid chain-id, mixed cases", "Ethermint-1", true, nil,
+		},
+		{
+			"invalid chain-id, special chars", "$&*#!-1", true, nil,
+		},
+		{
+			"invalid epoch, cannot start with 0", "ethermint-001", true, nil,
+		},
+		{
+			"invalid epoch, cannot invalid base", "ethermint-0x212", true, nil,
+		},
+		{
+			"invalid epoch, non-integer", "ethermint-ethermint", true, nil,
+		},
+		{
+			"invalid epoch, undefined", "ethermint-", true, nil,
+		},
+		{
+			"blank chain ID", " ", true, nil,
+		},
+		{
+			"empty chain ID", "", true, nil,
+		},
+		{
+			"long chain-id", "ethermint-" + strings.Repeat("1", 40), true, nil,
+		},
+	}
+
+	for _, tc := range testCases {
+		chainIDEpoch, err := ParseChainID(tc.chainID)
+		if tc.expError {
+			require.Error(t, err, tc.name)
+			require.Nil(t, chainIDEpoch)
+		} else {
+			require.NoError(t, err, tc.name)
+			require.Equal(t, tc.expInt, chainIDEpoch, tc.name)
+		}
+	}
+}
--- a/x/evm/handler.go
+++ b/x/evm/handler.go
@ -1,11 +1,9 @@
 package evm

 import (
-	"math/big"
-
 	"github.com/ethereum/go-ethereum/common"

-	emint "github.com/cosmos/ethermint/types"
+	ethermint "github.com/cosmos/ethermint/types"
 	"github.com/cosmos/ethermint/x/evm/types"

 	sdk "github.com/cosmos/cosmos-sdk/types"
@ -32,13 +30,13 @@ func NewHandler(k Keeper) sdk.Handler {
 // handleMsgEthereumTx handles an Ethereum specific tx
 func handleMsgEthereumTx(ctx sdk.Context, k Keeper, msg types.MsgEthereumTx) (*sdk.Result, error) {
 	// parse the chainID from a string to a base-10 integer
-	intChainID, ok := new(big.Int).SetString(ctx.ChainID(), 10)
-	if !ok {
-		return nil, sdkerrors.Wrap(emint.ErrInvalidChainID, ctx.ChainID())
+	chainIDEpoch, err := ethermint.ParseChainID(ctx.ChainID())
+	if err != nil {
+		return nil, err
 	}

 	// Verify signature and retrieve sender address
-	sender, err := msg.VerifySig(intChainID)
+	sender, err := msg.VerifySig(chainIDEpoch)
 	if err != nil {
 		return nil, err
 	}
@ -54,7 +52,7 @@ func handleMsgEthereumTx(ctx sdk.Context, k Keeper, msg types.MsgEthereumTx) (*s
 		Amount:       msg.Data.Amount,
 		Payload:      msg.Data.Payload,
 		Csdb:         k.CommitStateDB.WithContext(ctx),
-		ChainID:      intChainID,
+		ChainID:      chainIDEpoch,
 		TxHash:       &ethHash,
 		Sender:       sender,
 		Simulate:     ctx.IsCheckTx(),
@ -123,9 +121,9 @@ func handleMsgEthereumTx(ctx sdk.Context, k Keeper, msg types.MsgEthereumTx) (*s
 // handleMsgEthermint handles an sdk.StdTx for an Ethereum state transition
 func handleMsgEthermint(ctx sdk.Context, k Keeper, msg types.MsgEthermint) (*sdk.Result, error) {
 	// parse the chainID from a string to a base-10 integer
-	intChainID, ok := new(big.Int).SetString(ctx.ChainID(), 10)
-	if !ok {
-		return nil, sdkerrors.Wrap(emint.ErrInvalidChainID, ctx.ChainID())
+	chainIDEpoch, err := ethermint.ParseChainID(ctx.ChainID())
+	if err != nil {
+		return nil, err
 	}

 	txHash := tmtypes.Tx(ctx.TxBytes()).Hash()
@ -138,7 +136,7 @@ func handleMsgEthermint(ctx sdk.Context, k Keeper, msg types.MsgEthermint) (*sdk
 		Amount:       msg.Amount.BigInt(),
 		Payload:      msg.Payload,
 		Csdb:         k.CommitStateDB.WithContext(ctx),
-		ChainID:      intChainID,
+		ChainID:      chainIDEpoch,
 		TxHash:       &ethHash,
 		Sender:       common.BytesToAddress(msg.From.Bytes()),
 		Simulate:     ctx.IsCheckTx(),
--- a/x/evm/handler_test.go
+++ b/x/evm/handler_test.go
@ -21,6 +21,7 @@ import (

 	"github.com/cosmos/ethermint/app"
 	"github.com/cosmos/ethermint/crypto"
+	ethermint "github.com/cosmos/ethermint/types"
 	"github.com/cosmos/ethermint/x/evm"
 	"github.com/cosmos/ethermint/x/evm/keeper"
 	"github.com/cosmos/ethermint/x/evm/types"
@ -43,7 +44,7 @@ func (suite *EvmTestSuite) SetupTest() {
 	checkTx := false

 	suite.app = app.Setup(checkTx)
-	suite.ctx = suite.app.BaseApp.NewContext(checkTx, abci.Header{Height: 1, ChainID: "3", Time: time.Now().UTC()})
+	suite.ctx = suite.app.BaseApp.NewContext(checkTx, abci.Header{Height: 1, ChainID: "ethermint-3", Time: time.Now().UTC()})
 	suite.handler = evm.NewHandler(suite.app.EvmKeeper)
 	suite.querier = keeper.NewQuerier(suite.app.EvmKeeper)
 	suite.codec = codec.New()
@ -58,10 +59,7 @@ func (suite *EvmTestSuite) TestHandleMsgEthereumTx() {
 	suite.Require().NoError(err)
 	sender := ethcmn.HexToAddress(privkey.PubKey().Address().String())

-	var (
-		tx      types.MsgEthereumTx
-		chainID *big.Int
-	)
+	var tx types.MsgEthereumTx

 	testCases := []struct {
 		msg      string
@ -75,9 +73,8 @@ func (suite *EvmTestSuite) TestHandleMsgEthereumTx() {
 				tx = types.NewMsgEthereumTx(0, &sender, big.NewInt(100), 0, big.NewInt(10000), nil)

 				// parse context chain ID to big.Int
-				var ok bool
-				chainID, ok = new(big.Int).SetString(suite.ctx.ChainID(), 10)
-				suite.Require().True(ok)
+				chainID, err := ethermint.ParseChainID(suite.ctx.ChainID())
+				suite.Require().NoError(err)

 				// sign transaction
 				err = tx.Sign(chainID, privkey.ToECDSA())
@ -91,9 +88,8 @@ func (suite *EvmTestSuite) TestHandleMsgEthereumTx() {
 				tx = types.NewMsgEthereumTxContract(0, big.NewInt(100), 0, big.NewInt(10000), nil)

 				// parse context chain ID to big.Int
-				var ok bool
-				chainID, ok = new(big.Int).SetString(suite.ctx.ChainID(), 10)
-				suite.Require().True(ok)
+				chainID, err := ethermint.ParseChainID(suite.ctx.ChainID())
+				suite.Require().NoError(err)

 				// sign transaction
 				err = tx.Sign(chainID, privkey.ToECDSA())
@ -125,7 +121,7 @@ func (suite *EvmTestSuite) TestHandleMsgEthereumTx() {
 	}

 	for _, tc := range testCases {
-		suite.Run("", func() {
+		suite.Run(tc.msg, func() {
 			suite.SetupTest() // reset
 			//nolint
 			tc.malleate()