fix(client/tx): simulate with correct pk

CHANGELOG.md

@@ -65,6 +65,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### Bug Fixes
 
+* (client/tx) [#18472](https://github.com/cosmos/cosmos-sdk/pull/18472) Utilizes the correct Pubkey when simulating a transaction.
 * (baseapp) [#18383](https://github.com/cosmos/cosmos-sdk/pull/18383) Fixed a data race inside BaseApp.getContext, found by end-to-end (e2e) tests.
 * (client/server) [#18345](https://github.com/cosmos/cosmos-sdk/pull/18345) Consistently set viper prefix in client and server. It defaults for the binary name for both client and server.
 * (simulation) [#17911](https://github.com/cosmos/cosmos-sdk/pull/17911) Fix all problems with executing command `make test-sim-custom-genesis-fast` for simulation test.

client/tx/factory.go

@@ -15,6 +15,7 @@ import (
 	"github.com/cosmos/cosmos-sdk/client/flags"
 	codectypes "github.com/cosmos/cosmos-sdk/codec/types"
 	"github.com/cosmos/cosmos-sdk/crypto/keyring"
+	"github.com/cosmos/cosmos-sdk/crypto/keys/multisig"
 	"github.com/cosmos/cosmos-sdk/crypto/keys/secp256k1"
 	cryptotypes "github.com/cosmos/cosmos-sdk/crypto/types"
 	sdk "github.com/cosmos/cosmos-sdk/types"
@@ -33,6 +34,7 @@ type Factory struct {
 	timeoutHeight      uint64
 	gasAdjustment      float64
 	chainID            string
+	fromName           string
 	offline            bool
 	generateOnly       bool
 	memo               string
@@ -92,6 +94,7 @@ func NewFactoryCLI(clientCtx client.Context, flagSet *pflag.FlagSet) (Factory, e
 		accountRetriever:   clientCtx.AccountRetriever,
 		keybase:            clientCtx.Keyring,
 		chainID:            clientCtx.ChainID,
+		fromName:           clientCtx.FromName,
 		offline:            clientCtx.Offline,
 		generateOnly:       clientCtx.GenerateOnly,
 		gas:                gasSetting.Gas,
@@ -406,10 +409,8 @@ func (f Factory) BuildSimTx(msgs ...sdk.Msg) ([]byte, error) {
 	// Create an empty signature literal as the ante handler will populate with a
 	// sentinel pubkey.
 	sig := signing.SignatureV2{
-		PubKey: pk,
-		Data: &signing.SingleSignatureData{
-			SignMode: f.signMode,
-		},
+		PubKey:   pk,
+		Data:     f.getSimSignatureData(pk),
 		Sequence: f.Sequence(),
 	}
 	if err := txb.SetSignatures(sig); err != nil {
@@ -435,16 +436,13 @@ func (f Factory) getSimPK() (cryptotypes.PubKey, error) {
 		pk cryptotypes.PubKey = &secp256k1.PubKey{} // use default public key type
 	)
 
-	// Use the first element from the list of keys in order to generate a valid
-	// pubkey that supports multiple algorithms.
 	if f.simulateAndExecute && f.keybase != nil {
-		records, _ := f.keybase.List()
-		if len(records) == 0 {
-			return nil, errors.New("cannot build signature for simulation, key records slice is empty")
+		record, err := f.keybase.Key(f.fromName)
+		if err != nil {
+			return nil, err
 		}
 
-		// take the first record just for simulation purposes
-		pk, ok = records[0].PubKey.GetCachedValue().(cryptotypes.PubKey)
+		pk, ok = record.PubKey.GetCachedValue().(cryptotypes.PubKey)
 		if !ok {
 			return nil, errors.New("cannot build signature for simulation, failed to convert proto Any to public key")
 		}
@@ -453,6 +451,25 @@ func (f Factory) getSimPK() (cryptotypes.PubKey, error) {
 	return pk, nil
 }
 
+// getSimSignatureData based on the pubKey type gets the correct SignatureData type
+// to use for building a simulation tx.
+func (f Factory) getSimSignatureData(pk cryptotypes.PubKey) signing.SignatureData {
+	if multisigPubKey, ok := pk.(*multisig.LegacyAminoPubKey); ok {
+		multiSignatureData := make([]signing.SignatureData, 0, multisigPubKey.Threshold)
+		for i := uint32(0); i < multisigPubKey.Threshold; i++ {
+			multiSignatureData = append(multiSignatureData, &signing.SingleSignatureData{
+				SignMode: f.SignMode(),
+			})
+		}
+		return &signing.MultiSignatureData{
+			Signatures: multiSignatureData,
+		}
+	}
+	return &signing.SingleSignatureData{
+		SignMode: f.signMode,
+	}
+}
+
 // Prepare ensures the account defined by ctx.GetFromAddress() exists and
 // if the account number and/or the account sequence number are zero (not set),
 // they will be queried for and set on the provided Factory.