Bitcoin Testnet - Encountering Error 7 During Input Signing

[Arunpandiaraja]

I'm using an external wallet that returns a signature when i try to broadcast test btc like 0.01 its throwing SigningOutput {error: 7} but if i send 0.001 transaction is getting broadcasted, This is my Testnet balance - 0.02958546 BTC. Not sure what i'm missing here, any help would be much appreciated. Below is my code,

Signature (Testnet) :
b033657aa195c1b0005483c7b1953b7aaa3fb570c4ad89d5cf532405cda212167632a78830aacbfff0b1e4d385d680ab7e432362e2ced215bd165ee24e8eb53a00

export const getEncodedInput = async (inputs: any) => {
  const { utxos, fromAddress, outputAmmount, toAddress, feeRate } = inputs
  const walletCore = await initWasm()

  const unspentTransaction = []

  const utxo = utxos.map(
    (utxo: { txid: any; vout: any; value: any; satoshis: number }) => {
      return TW.Bitcoin.Proto.UnspentTransaction.create({
        outPoint: {
          hash: Buffer.from(utxo.txid, 'hex').reverse(),
          index: utxo.vout,
          sequence: 4294967295, // default sequence
        },
        amount: new Long(utxo.value),
        script: walletCore.BitcoinScript.lockScriptForAddress(
          fromAddress,
          walletCore.CoinType.bitcoin
        ).data(),
      })
    }
  )

  const txInput = TW.Bitcoin.Proto.SigningInput.create({
    hashType: walletCore.BitcoinSigHashType.all.value,
    coinType: walletCore.CoinType.bitcoin.value,
    amount: new Long(outputAmmount),
    toAddress: toAddress,
    lockTime: 0,
    changeAddress: fromAddress,
    utxo: utxo,
    byteFee: new Long(9),
  })

  return TW.Bitcoin.Proto.SigningInput.encode(txInput).finish()
}

export const generatePreSignTxHash = async (txObject: any) => {
  const {
    version,
    utxos,
    outputs,
    lockTime,
    fromAddress,
    forFeeAmount,
    feeRate,
    outputAmmount,
    toAddress,
  } = txObject

  const walletCore = await initWasm()

  const inputEncoded = await getEncodedInput({
    utxos,
    fromAddress,
    outputAmmount,
    toAddress,
  })

  const preimageOutputData = walletCore.TransactionCompiler.preImageHashes(
    walletCore.CoinType.bitcoin,
    inputEncoded
  )

  const preimageOutput =
    TW.Bitcoin.Proto.PreSigningOutput.decode(preimageOutputData)

  const inputDataHashHex = walletCore.HexCoding.encode(
    preimageOutput.hashPublicKeys[0].dataHash as Uint8Array
  )

  return inputDataHashHex
}


export const getSignedTxHashBtc = async (signature: string, txObject: any) => {
  if (signature == '') {
    return ''
  }

// removing Recovery ID from the signature
  const _signature = signature.slice(0, -2)

  const walletCore = await initWasm()

  const inputEncoded = await getEncodedInput(txObject)

  const pubKey = localStorageService.generatedPublicKey.get()

  const pubData = walletCore.HexCoding.decode(pubKey ?? '')

  const publicKey = walletCore.PublicKey.createWithData(
    pubData,
    walletCore.PublicKeyType.secp256k1
  )

  const preimageOutputEncoded = await generatePreSignTxHash(txObject)

  const preimageOutput = walletCore.HexCoding.decode(preimageOutputEncoded)

  const isValid = publicKey.verify(
    Buffer.from(_signature, 'hex'),
    preimageOutput
  )

  const signData = walletCore.HexCoding.decode(_signature)

  const publicKeys = walletCore.DataVector.createWithData(pubData)

  walletCore.PrivateKey.create().signAsDER(signData)

  const rawSignature = _signature

  const joseSignature = Buffer.from(rawSignature, 'hex')

  const derSignature = ecdsaSigFormatter.joseToDer(joseSignature, 'ES256')

  const signatures = walletCore.DataVector.createWithData(derSignature)

  const outputData = walletCore.TransactionCompiler.compileWithSignatures(
    walletCore.CoinType.bitcoin,
    inputEncoded,
    signatures,
    publicKeys
  )

  const output = TW.Bitcoin.Proto.SigningOutput.decode(outputData)

  const rawTx = walletCore.HexCoding.encode(output.encoded)
  const data = await pushTx(rawTx.substring(2))
  return data
}

[Arunpandiaraja]

Hi @satoshiotomakan, can u please check this?

[satoshiotomakan]

Hi @Arunpandiaraja, did you try to call AnySigner.sign directly instead of transaction compiling? Does it work well?

[satoshiotomakan]

The problem can be that getSignedTxHashBtc takes a signature hex, but you should make sure if it's encoded as ASN.1 DER and truly belong to the given calculated sighash