fix: fix NewSeed tx signinng process

app/utils/vrf_key.go

@@ -124,6 +124,27 @@ func (v *VRFKey) SignTransaction(
 		Address:       account.GetAddress().String(),
 	}
 
+	// For SIGN_MODE_DIRECT, calling SetSignatures calls setSignerInfos on
+	// TxBuilder under the hood, and SignerInfos is needed to generate the sign
+	// bytes. This is the reason for setting SetSignatures here, with a nil
+	// signature.
+	//
+	// Note: This line is not needed for SIGN_MODE_LEGACY_AMINO, but putting it
+	// also doesn't affect its generated sign bytes, so for code's simplicity
+	// sake, we put it here.
+	nilSig := txsigning.SignatureV2{
+		PubKey: v.PubKey,
+		Data: &txsigning.SingleSignatureData{
+			SignMode:  signMode,
+			Signature: nil,
+		},
+		Sequence: account.GetSequence(),
+	}
+
+	if err := txBuilder.SetSignatures(nilSig); err != nil {
+		return sigV2, err
+	}
+
 	bytesToSign, err := authsigning.GetSignBytesAdapter(
 		context.Background(),
 		txConfig.SignModeHandler(),

proto/sedachain/randomness/v1/tx.proto

@@ -11,9 +11,9 @@ service Msg {
 }
 
 message MsgNewSeed {
-  option (cosmos.msg.v1.signer) = "proposer";
+  option (cosmos.msg.v1.signer) = "prover";
 
-  string proposer = 1;
+  string prover = 1; // address of VRF key used to produce proof
   string pi = 2; // VRF proof
   string beta = 3; // VRF hash
 }

x/randomness/keeper/abci.go

@@ -66,19 +66,19 @@ func (h *ProposalHandler) PrepareProposalHandler(
 		}
 
 		// generate and sign NewSeed tx
-		pubKey, err := keeper.GetValidatorVRFPubKey(ctx, sdk.ConsAddress(req.ProposerAddress).String())
+		vrfPubKey, err := keeper.GetValidatorVRFPubKey(ctx, sdk.ConsAddress(req.ProposerAddress).String())
 		if err != nil {
 			return nil, err
 		}
-		account := authKeeper.GetAccount(ctx, sdk.AccAddress(pubKey.Address().Bytes()))
-		err = account.SetPubKey(pubKey) // checked later when signing tx with VRF key
+		account := authKeeper.GetAccount(ctx, sdk.AccAddress(vrfPubKey.Address().Bytes()))
+		err = account.SetPubKey(vrfPubKey) // checked later when signing tx with VRF key
 		if err != nil {
 			return nil, err
 		}
 		newSeedTx, newSeedTxBz, err := generateAndSignNewSeedTx(ctx, txConfig, vrfSigner, account, &types.MsgNewSeed{
-			Proposer: sdk.AccAddress(req.ProposerAddress).String(),
-			Pi:       hex.EncodeToString(pi),
-			Beta:     hex.EncodeToString(beta),
+			Prover: account.GetAddress().String(),
+			Pi:     hex.EncodeToString(pi),
+			Beta:   hex.EncodeToString(beta),
 		})
 		if err != nil {
 			return nil, err
@@ -148,11 +148,6 @@ func (h *ProposalHandler) ProcessProposalHandler(
 			return &abci.ResponseProcessProposal{Status: abci.ResponseProcessProposal_REJECT}, err
 		}
 
-		if msg.Proposer != string(sdk.AccAddress(req.ProposerAddress).String()) {
-			return &abci.ResponseProcessProposal{Status: abci.ResponseProcessProposal_REJECT},
-				fmt.Errorf("the NewSeed transaction must be from the block proposer")
-		}
-
 		// get block proposer's validator public key
 		pubKey, err := keeper.GetValidatorVRFPubKey(ctx, sdk.ConsAddress(req.ProposerAddress).String())
 		if err != nil {

x/staking/keeper/msg_server.go

@@ -51,11 +51,11 @@ func (k msgServer) CreateValidatorWithVRF(ctx context.Context, msg *types.MsgCre
 	k.accountKeeper.SetAccount(ctx, acc)
 
 	// register VRF public key to validator consensus address
-	pubKey, ok := msg.Pubkey.GetCachedValue().(cryptotypes.PubKey)
+	consPubKey, ok := msg.Pubkey.GetCachedValue().(cryptotypes.PubKey)
 	if !ok {
-		return nil, errorsmod.Wrapf(sdkerrors.ErrInvalidType, "Expecting cryptotypes.PubKey, got %T", pubKey)
+		return nil, errorsmod.Wrapf(sdkerrors.ErrInvalidType, "Expecting cryptotypes.PubKey, got %T", consPubKey)
 	}
-	k.randomnessKeeper.SetValidatorVRFPubKey(ctx, sdk.GetConsAddress(pubKey).String(), vrfPubKey)
+	k.randomnessKeeper.SetValidatorVRFPubKey(ctx, sdk.GetConsAddress(consPubKey).String(), vrfPubKey)
 
 	sdkMsg := new(stakingtypes.MsgCreateValidator)
 	sdkMsg.Description = msg.Description