[issue-#1389] add multisig tx support (#1390)

* [issue-#1389] add multisig tx support

* [issue-#1389] add changes in CHANGELOG improvements

* [issue-#1389] fix style issue

* [issue-#1389] fix style issue

* [issue-#1389] add tests

CHANGELOG.md

@@ -63,6 +63,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (rpc) [#1352](https://github.com/evmos/ethermint/pull/1352) Make the grpc queries run concurrently, don't block the consensus state machine.
 * (cli) [#1360](https://github.com/evmos/ethermint/pull/1360) Introduce a new `grpc-only` flag, such that when enabled, will start the node in a query-only mode. Note, gRPC MUST be enabled with this flag.
 * (rpc) [#1378](https://github.com/evmos/ethermint/pull/1378) Add support for EVM RPC metrics
+* (ante) [#1390](https://github.com/evmos/ethermint/pull/1390) Added multisig tx support.
 
 ### Bug Fixes
 

app/ante/ante.go

@@ -6,6 +6,7 @@ import (
 
 	tmlog "github.com/tendermint/tendermint/libs/log"
 
+	"github.com/cosmos/cosmos-sdk/crypto/types/multisig"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
 	"github.com/cosmos/cosmos-sdk/types/tx/signing"
@@ -99,12 +100,48 @@ var _ authante.SignatureVerificationGasConsumer = DefaultSigVerificationGasConsu
 func DefaultSigVerificationGasConsumer(
 	meter sdk.GasMeter, sig signing.SignatureV2, params authtypes.Params,
 ) error {
-	// support for ethereum ECDSA secp256k1 keys
+	pubkey := sig.PubKey
-	_, ok := sig.PubKey.(*ethsecp256k1.PubKey)
+	switch pubkey := pubkey.(type) {
-	if ok {
+	case *ethsecp256k1.PubKey:
 		meter.ConsumeGas(secp256k1VerifyCost, "ante verify: eth_secp256k1")
 		return nil
+
+	case multisig.PubKey:
+		// Multisig keys
+		multisignature, ok := sig.Data.(*signing.MultiSignatureData)
+		if !ok {
+			return fmt.Errorf("expected %T, got, %T", &signing.MultiSignatureData{}, sig.Data)
+		}
+		return ConsumeMultisignatureVerificationGas(meter, multisignature, pubkey, params, sig.Sequence)
+
+	default:
+		return authante.DefaultSigVerificationGasConsumer(meter, sig, params)
+	}
+}
+
+// ConsumeMultisignatureVerificationGas consumes gas from a GasMeter for verifying a multisig pubkey signature
+func ConsumeMultisignatureVerificationGas(
+	meter sdk.GasMeter, sig *signing.MultiSignatureData, pubkey multisig.PubKey,
+	params authtypes.Params, accSeq uint64,
+) error {
+	size := sig.BitArray.Count()
+	sigIndex := 0
+
+	for i := 0; i < size; i++ {
+		if !sig.BitArray.GetIndex(i) {
+			continue
+		}
+		sigV2 := signing.SignatureV2{
+			PubKey:   pubkey.GetPubKeys()[i],
+			Data:     sig.Signatures[sigIndex],
+			Sequence: accSeq,
+		}
+		err := DefaultSigVerificationGasConsumer(meter, sigV2, params)
+		if err != nil {
+			return err
+		}
+		sigIndex++
 	}
 
-	return authante.DefaultSigVerificationGasConsumer(meter, sig, params)
+	return nil
 }

app/ante/ante_test.go

@@ -2,13 +2,22 @@ package ante_test
 
 import (
 	"errors"
+	"fmt"
 	"math/big"
 	"strings"
 	"time"
 
 	sdkmath "cosmossdk.io/math"
+	kmultisig "github.com/cosmos/cosmos-sdk/crypto/keys/multisig"
 
+	"github.com/cosmos/cosmos-sdk/crypto/keys/ed25519"
+	"github.com/cosmos/cosmos-sdk/crypto/keys/secp256r1"
+	cryptotypes "github.com/cosmos/cosmos-sdk/crypto/types"
+	"github.com/cosmos/cosmos-sdk/crypto/types/multisig"
+	"github.com/cosmos/cosmos-sdk/simapp"
 	"github.com/cosmos/cosmos-sdk/types/tx/signing"
+	"github.com/cosmos/cosmos-sdk/x/auth/migrations/legacytx"
+
 	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
 	"github.com/cosmos/cosmos-sdk/x/authz"
 
@@ -16,6 +25,8 @@ import (
 
 	"github.com/ethereum/go-ethereum/core/types"
 	ethparams "github.com/ethereum/go-ethereum/params"
+	"github.com/evmos/ethermint/app/ante"
+	"github.com/evmos/ethermint/crypto/ethsecp256k1"
 	"github.com/evmos/ethermint/tests"
 	evmtypes "github.com/evmos/ethermint/x/evm/types"
 
@@ -914,3 +925,93 @@ func (suite AnteTestSuite) TestAnteHandlerWithParams() {
 	}
 	suite.evmParamsOption = nil
 }
+
+func (suite *AnteTestSuite) TestConsumeSignatureVerificationGas() {
+	params := authtypes.DefaultParams()
+	msg := []byte{1, 2, 3, 4}
+	cdc := simapp.MakeTestEncodingConfig().Amino
+
+	p := authtypes.DefaultParams()
+	skR1, _ := secp256r1.GenPrivKey()
+	pkSet1, sigSet1, err := generatePubKeysAndSignatures(5, msg, false)
+	suite.Require().NoError(err)
+
+	multisigKey1 := kmultisig.NewLegacyAminoPubKey(2, pkSet1)
+	multisignature1 := multisig.NewMultisig(len(pkSet1))
+	expectedCost1 := expectedGasCostByKeys(pkSet1)
+	
+	for i := 0; i < len(pkSet1); i++ {
+		stdSig := legacytx.StdSignature{PubKey: pkSet1[i], Signature: sigSet1[i]}
+		sigV2, err := legacytx.StdSignatureToSignatureV2(cdc, stdSig)
+		suite.Require().NoError(err)
+		err = multisig.AddSignatureV2(multisignature1, sigV2, pkSet1)
+		suite.Require().NoError(err)
+	}
+
+	type args struct {
+		meter  sdk.GasMeter
+		sig    signing.SignatureData
+		pubkey cryptotypes.PubKey
+		params authtypes.Params
+	}
+	tests := []struct {
+		name        string
+		args        args
+		gasConsumed uint64
+		shouldErr   bool
+	}{
+		{"PubKeyEd25519", args{sdk.NewInfiniteGasMeter(), nil, ed25519.GenPrivKey().PubKey(), params}, p.SigVerifyCostED25519, true},
+		{"PubKeyEthSecp256k1", args{sdk.NewInfiniteGasMeter(), nil, pkSet1[0], params}, 21_000, false},
+		{"PubKeySecp256r1", args{sdk.NewInfiniteGasMeter(), nil, skR1.PubKey(), params}, p.SigVerifyCostSecp256r1(), false},
+		{"Multisig", args{sdk.NewInfiniteGasMeter(), multisignature1, multisigKey1, params}, expectedCost1, false},
+		{"unknown key", args{sdk.NewInfiniteGasMeter(), nil, nil, params}, 0, true},
+	}
+	for _, tt := range tests {
+		sigV2 := signing.SignatureV2{
+			PubKey:   tt.args.pubkey,
+			Data:     tt.args.sig,
+			Sequence: 0, // Arbitrary account sequence
+		}
+		err := ante.DefaultSigVerificationGasConsumer(tt.args.meter, sigV2, tt.args.params)
+
+		if tt.shouldErr {
+			suite.Require().NotNil(err)
+		} else {
+			suite.Require().Nil(err)
+			suite.Require().Equal(tt.gasConsumed, tt.args.meter.GasConsumed(), fmt.Sprintf("%d != %d", tt.gasConsumed, tt.args.meter.GasConsumed()))
+		}
+	}
+}
+
+func generatePubKeysAndSignatures(n int, msg []byte, _ bool) (pubkeys []cryptotypes.PubKey, signatures [][]byte, err error) {
+	pubkeys = make([]cryptotypes.PubKey, n)
+	signatures = make([][]byte, n)
+	for i := 0; i < n; i++ {
+		privkey, err := ethsecp256k1.GenerateKey()
+		if err != nil {
+			return nil, nil, err
+		}
+
+		pubkeys[i] = privkey.PubKey()
+		signatures[i], _ = privkey.Sign(msg)
+	}
+	return
+}
+
+func expectedGasCostByKeys(pubkeys []cryptotypes.PubKey) uint64 {
+	cost := uint64(0)
+	for _, pubkey := range pubkeys {
+		pubkeyType := strings.ToLower(fmt.Sprintf("%T", pubkey))
+		switch {
+		case strings.Contains(pubkeyType, "ed25519"):
+			cost += authtypes.DefaultParams().SigVerifyCostED25519
+		case strings.Contains(pubkeyType, "ethsecp256k1"):
+			cost += 21_000
+		case strings.Contains(pubkeyType, "secp256k1"):
+			cost += authtypes.DefaultParams().SigVerifyCostSecp256k1
+		default:
+			panic("unexpected key type")
+		}
+	}
+	return cost
+}