use custom sigverify ante handler to prevent same tx inclusion (#755)

custom/auth/ante/ante.go

@@ -65,7 +65,7 @@ func NewAnteHandler(options HandlerOptions) (sdk.AnteHandler, error) {
 		cosmosante.NewSetPubKeyDecorator(options.AccountKeeper), // SetPubKeyDecorator must be called before all signature verification decorators
 		cosmosante.NewValidateSigCountDecorator(options.AccountKeeper),
 		cosmosante.NewSigGasConsumeDecorator(options.AccountKeeper, sigGasConsumer),
-		cosmosante.NewSigVerificationDecorator(options.AccountKeeper, options.SignModeHandler),
+		NewSigVerificationDecorator(options.AccountKeeper, options.SignModeHandler),
 		cosmosante.NewIncrementSequenceDecorator(options.AccountKeeper),
 		ibcante.NewAnteDecorator(options.IBCChannelKeeper),
 	), nil

custom/auth/ante/ante_test.go

@@ -1,6 +1,8 @@
 package ante_test
 
 import (
+	"fmt"
+	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/suite"
@@ -11,12 +13,14 @@ import (
 
 	"github.com/cosmos/cosmos-sdk/client"
 	"github.com/cosmos/cosmos-sdk/client/tx"
+	"github.com/cosmos/cosmos-sdk/crypto/keys/secp256k1"
 	cryptotypes "github.com/cosmos/cosmos-sdk/crypto/types"
 	"github.com/cosmos/cosmos-sdk/simapp"
 	"github.com/cosmos/cosmos-sdk/testutil/testdata"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	"github.com/cosmos/cosmos-sdk/types/tx/signing"
 	xauthsigning "github.com/cosmos/cosmos-sdk/x/auth/signing"
+	"github.com/cosmos/cosmos-sdk/x/auth/types"
 	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
 
 	terraapp "github.com/terra-money/core/app"
@@ -115,3 +119,40 @@ func (suite *AnteTestSuite) CreateTestTx(privs []cryptotypes.PrivKey, accNums []
 func TestAnteTestSuite(t *testing.T) {
 	suite.Run(t, new(AnteTestSuite))
 }
+
+func generatePubKeysAndSignatures(n int, msg []byte, _ bool) (pubkeys []cryptotypes.PubKey, signatures [][]byte) {
+	pubkeys = make([]cryptotypes.PubKey, n)
+	signatures = make([][]byte, n)
+	for i := 0; i < n; i++ {
+		var privkey cryptotypes.PrivKey = secp256k1.GenPrivKey()
+
+		// TODO: also generate ed25519 keys as below when ed25519 keys are
+		//  actually supported, https://github.com/cosmos/cosmos-sdk/issues/4789
+		// for now this fails:
+		//if rand.Int63()%2 == 0 {
+		//	privkey = ed25519.GenPrivKey()
+		//} else {
+		//	privkey = secp256k1.GenPrivKey()
+		//}
+
+		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 += types.DefaultParams().SigVerifyCostED25519
+		case strings.Contains(pubkeyType, "secp256k1"):
+			cost += types.DefaultParams().SigVerifyCostSecp256k1
+		default:
+			panic("unexpected key type")
+		}
+	}
+	return cost
+}