Cannot spend 2 taproot output in one transaction

[phanquocky]

Here is My code for spend 2 taproot output

func CreateTaprootAddressWithData(pubkey *secp256k1.PublicKey, data [32]byte) (*btcutil.AddressTaproot, *txscript.ControlBlock, *chainhash.Hash, error) {
	fmt.Printf("DATA: %x \n", data)
	tapleaf := txscript.NewBaseTapLeaf(data[:])
	tapScriptTree := txscript.AssembleTaprootScriptTree(tapleaf)
	tapScriptRootHash := tapScriptTree.LeafMerkleProofs[0].RootNode.TapHash()

	// taprootKey = internalKey + (h_tapTweak(internalKey || merkleRoot)*G)
	outputKey := txscript.ComputeTaprootOutputKey(pubkey, tapScriptRootHash[:])

	address, err := btcutil.NewAddressTaproot(schnorr.SerializePubKey(outputKey), &chaincfg.TestNet3Params)
	if err != nil {
		log.Println("Cannot create taproot address!")
		return nil, nil, nil, err
	}

	// Generate Proof and store ctrBlock
	ctrBlock := tapScriptTree.LeafMerkleProofs[0].ToControlBlock(pubkey)

	//// using ctrBlock to verify the data in this address
	witnessProgram := address.WitnessProgram() // x in address

	//verify
	err = txscript.VerifyTaprootLeafCommitment(&ctrBlock, witnessProgram, data[:])
	if err != nil {
		log.Println("Verify failse")
	}
	log.Println("TapscriptRootHash: ", tapScriptRootHash)
	log.Println("Verify success")
	return address, &ctrBlock, &tapScriptRootHash, nil
}

func TestMultipleInput(t *testing.T) {
	client := client.New()
	fmt.Println("client: ", client)
	wallet.OpenWallet(client)
	defaultAddress, err := btcutil.DecodeAddress(ADDRESS_TEST, &chaincfg.TestNet3Params)
	DATA1 := "556777d2cb5192ecee2fbc5b60d28f7877401fc422df12e8ef8a98f57070d6f9"
	DATA2 := "556777d2cb5192ecee2fbc5b60d28f7877401fc422df12e8ef8a98f57070d6f2"
	if err != nil {
		log.Fatal("Can not decode address")
	}
	wif, err := client.DumpPrivKey(defaultAddress)
	if err != nil {
		log.Fatal("Can not dump privkey!")
	}

	data1, _ := hex.DecodeString(DATA1)

	address1, ctrlBlock1, scriptRootHash1, err := CreateTaprootAddressWithData(wif.PrivKey.PubKey(), [32]byte(data1[:]))
	if err != nil {
		log.Fatal(err)
	}
	log.Println("address1: ", address1)
	log.Println("ctrl block 1: ", ctrlBlock1)
	log.Println("script root hash 1: ", scriptRootHash1)
	data2, _ := hex.DecodeString(DATA2)

	address2, ctrlBlock2, scriptRootHash2, err := CreateTaprootAddressWithData(wif.PrivKey.PubKey(), [32]byte(data2[:]))
	if err != nil {
		log.Fatal(err)
	}
	log.Println("address 2: ", address2)
	log.Println("ctrl block 2: ", ctrlBlock2)
	log.Println("script root hash 2: ", scriptRootHash2)

	// ctrblock1bytes, _ := ctrlBlock1.ToBytes()
	// ctrblock2bytes, _ := ctrlBlock2.ToBytes()

	txID1 := "16064b73d4570359552a5cd165ef9a80b2a4e24d2844f2891cea93c2023087a0"
	txID1bytes, _ := hex.DecodeString(txID1)
	// reverse TxID1Bytes
	for i, j := 0, len(txID1bytes)-1; i < j; i, j = i+1, j-1 {
		txID1bytes[i], txID1bytes[j] = txID1bytes[j], txID1bytes[i]
	}
	vout1 := uint32(0)

	txID2 := "82a6035084b92d7d4c822a829a3869bcbec00b86ea2ff0ceafd1e6d7d3c34e6a"
	txID2bytes, _ := hex.DecodeString(txID2)
	// reverse TxID2Bytes
	for i, j := 0, len(txID2bytes)-1; i < j; i, j = i+1, j-1 {
		txID2bytes[i], txID2bytes[j] = txID2bytes[j], txID2bytes[i]
	}
	vout2 := uint32(0)

	commitTxHash1, _ := chainhash.NewHash(txID1bytes)
	commitTxHash2, _ := chainhash.NewHash(txID2bytes)

	tx := wire.NewMsgTx(2)
	tx.AddTxIn(&wire.TxIn{
		PreviousOutPoint: wire.OutPoint{
			Hash:  *commitTxHash1,
			Index: uint32(vout1),
		},
	})

	tx.AddTxIn(&wire.TxIn{
		PreviousOutPoint: wire.OutPoint{
			Hash:  *commitTxHash2,
			Index: uint32(vout2),
		},
	})

	pkOutput, _ := txscript.PayToAddrScript(defaultAddress)
	txOut := wire.NewTxOut(1000, pkOutput)
	tx.AddTxOut(txOut)

	commitTx1, err := client.GetRawTransaction(commitTxHash1)
	if err != nil {
		fmt.Println("Cannot get commitTx1")
		fmt.Println(err)
	}
	commitTx2, _ := client.GetRawTransaction(commitTxHash2)
	fmt.Println("commitTX", commitTx1)
	inputFetcher1 := txscript.NewCannedPrevOutputFetcher(
		commitTx1.MsgTx().TxOut[vout1].PkScript,
		commitTx1.MsgTx().TxOut[vout1].Value,
	)
	inputFetcher2 := txscript.NewCannedPrevOutputFetcher(
		commitTx2.MsgTx().TxOut[vout2].PkScript,
		commitTx2.MsgTx().TxOut[vout2].Value,
	)
	fmt.Println("END!!!")

	sigHashes1 := txscript.NewTxSigHashes(tx, inputFetcher1)
	sigHashes2 := txscript.NewTxSigHashes(tx, inputFetcher2)

	sig1, err := txscript.RawTxInTaprootSignature(tx, sigHashes1, 0, commitTx1.MsgTx().TxOut[vout1].Value, wif.PrivKey.PubKey().SerializeCompressed(), scriptRootHash1.CloneBytes(), txscript.SigHashAll, wif.PrivKey)
	if err != nil {
		fmt.Println("Cannot sign input 0")
		fmt.Println(err)
	}
	sig2, err := txscript.RawTxInTaprootSignature(tx, sigHashes2, 1, commitTx2.MsgTx().TxOut[vout2].Value, wif.PrivKey.PubKey().SerializeCompressed(), scriptRootHash2.CloneBytes(), txscript.SigHashAll, wif.PrivKey)

	// tx.TxIn[0].Witness = wire.TxWitness{sig1, commitTx1.MsgTx().TxOut[vout1].PkScript, ctrblock1bytes}
	// tx.TxIn[1].Witness = wire.TxWitness{sig2, commitTx2.MsgTx().TxOut[vout2].PkScript, ctrblock2bytes}
	tx.TxIn[0].Witness = wire.TxWitness{sig1}
	tx.TxIn[1].Witness = wire.TxWitness{sig2}

	var buf bytes.Buffer
	_ = tx.Serialize(&buf)
	fmt.Printf("Raw tx: %x\n", buf.Bytes())
	hashTx, err := client.SendRawTransaction(tx, true)
	if err != nil {
		log.Println("Cannot send raw transaction!")
		log.Println(err)
		log.Fatal()
	}
	log.Println("Success!!! : ", hashTx)
}

Here is my Log

client:  &{0 0xc0001503c0 0xac7740 0xc0001360f0 <nil> {0 0} <nil> {0 0} false false 0xc0002282d0 0 {0 0} map[] 0xc0002282a0 <nil> {0 0} 0xc00029fea8 0xc0002b25a0 0xc0002b2600 0xc00002a480 0xc00002aa80 0xc00002aae0 {{} {{} {} 17179869184} 0}}
2023/10/12 11:28:59 Open wallet success!
DATA: 556777d2cb5192ecee2fbc5b60d28f7877401fc422df12e8ef8a98f57070d6f9 
2023/10/12 11:28:59 TapscriptRootHash:  3159bc4857560c06461a1623104db4e7a2388c1b1ef10dfc8fd5ed707665aecd
2023/10/12 11:28:59 Verify success
2023/10/12 11:28:59 address1:  tb1p7etvxj3ynwfytreatxeqeyzlu80c79utz8wt9hxurpgq7nf38x2svhwtvr
2023/10/12 11:28:59 ctrl block 1:  &{0xc0002b14f0 true 192 []}
2023/10/12 11:28:59 script root hash 1:  3159bc4857560c06461a1623104db4e7a2388c1b1ef10dfc8fd5ed707665aecd
DATA: 556777d2cb5192ecee2fbc5b60d28f7877401fc422df12e8ef8a98f57070d6f2 
2023/10/12 11:28:59 TapscriptRootHash:  1d33e43145755039a37058ff35089f5bcb81daa0b07f1db4ab7880d8f4ca058f
2023/10/12 11:28:59 Verify success
2023/10/12 11:28:59 address 2:  tb1p0mye2443yrqp8qtqs0czflzx3gjmmfula4gltt7mjfz4665xhu7seswsaz
2023/10/12 11:28:59 ctrl block 2:  &{0xc0002b1770 true 192 []}
2023/10/12 11:28:59 script root hash 2:  1d33e43145755039a37058ff35089f5bcb81daa0b07f1db4ab7880d8f4ca058f
commitTX &{0xc00006ab80 <nil> <nil> <nil> -1}
END!!!
Raw tx: 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
2023/10/12 11:28:59 Cannot send raw transaction!
2023/10/12 11:28:59 -25: TX rejected: failed to validate input c20d14a99ef80bbaf630fa6dfadfdba0b7f71f2e724832a2ac1a2aa22ee6faa2:0 which references output 16064b73d4570359552a5cd165ef9a80b2a4e24d2844f2891cea93c2023087a0:0 -  (input witness [8da366fac7e6f9018cadf37f2f81af618f950a736b0c20224bd57a58f5533c5f6469c1b0bff78d857162b0725dd8c183212d659c9130019fc0fec0a611d03a4b01], input script bytes , prev output script bytes 5120f656c34a249b92458f3d59b20c905fe1df8f178b11dcb2dcdc18500f4d313995)
2023/10/12 11:28:59 
FAIL    demo_btc_assets/address 0.055s
FAIL

I decode rawtransaction

$ btcctl decoderawtransaction 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
{
  "txid": "c20d14a99ef80bbaf630fa6dfadfdba0b7f71f2e724832a2ac1a2aa22ee6faa2",
  "version": 2,
  "locktime": 0,
  "vin": [
    {
      "txid": "16064b73d4570359552a5cd165ef9a80b2a4e24d2844f2891cea93c2023087a0",
      "vout": 0,
      "scriptSig": {
        "asm": "",
        "hex": ""
      },
      "txinwitness": [
        "8da366fac7e6f9018cadf37f2f81af618f950a736b0c20224bd57a58f5533c5f6469c1b0bff78d857162b0725dd8c183212d659c9130019fc0fec0a611d03a4b01"
      ],
      "sequence": 0
    },
    {
      "txid": "82a6035084b92d7d4c822a829a3869bcbec00b86ea2ff0ceafd1e6d7d3c34e6a",
      "vout": 0,
      "scriptSig": {
        "asm": "",
        "hex": ""
      },
      "txinwitness": [
        "36c0e2e023d70baa5807f5d8b14f6a3f873f8c81cc344b3dd6ea4d4c502446f49c754736465c017464dcbacabb08be18cb0444a283a905b5b4a2b8d16e4cb7e301"
      ],
      "sequence": 0
    }
  ],
  "vout": [
    {
      "value": 0.00001,
      "n": 0,
      "scriptPubKey": {
        "asm": "OP_DUP OP_HASH160 0a740a3bb83b1c9b7c44f2089aa33075a0d13a9b OP_EQUALVERIFY OP_CHECKSIG",
        "hex": "76a9140a740a3bb83b1c9b7c44f2089aa33075a0d13a9b88ac",
        "reqSigs": 1,
        "type": "pubkeyhash",
        "addresses": [
          "mgUE4a5G1tnKLxmRTPCzQSURueDwzPnMSm"
        ]
      }
    }
  ]
}

I'm sure the above unspent taproot output is true, and I try spend 1 taproot output is fine but 2 taproot outputs don't work

[guggero]

You need to use a single input fetcher and sighashes for both signature. But you need to add both previous outputs to the same input fetcher, so you need to use MultiPrevOutFetcher instead of the canned one.