@ledgerhq/hw-app-btc

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@ledgerhq/hw-app-btc

Ledger Hardware Wallet BTC JavaScript bindings. Also supports many altcoins.

API

Table of Contents

• AddressFormat
• Btc
  • Parameters
  • Examples
  • getWalletPublicKey
    • Parameters
    • Examples
  • signMessageNew
    • Parameters
    • Examples
  • createPaymentTransactionNew
    • Parameters
    • Examples
  • signP2SHTransaction
    • Parameters
    • Examples
  • splitTransaction
    • Parameters
    • Examples
  • serializeTransactionOutputs
    • Parameters
    • Examples
  • serializeTransaction
    • Parameters
  • displayTransactionDebug
    • Parameters
• TransactionInput
  • Properties
• TransactionOutput
  • Properties
• Transaction
  • Properties

AddressFormat

address format is one of legacy | p2sh | bech32

Type: ("legacy" | "p2sh" | "bech32")

Btc

Bitcoin API.

Parameters

• transport Transport<any>
• scrambleKey string (optional, default "BTC")

Examples

import Btc from "@ledgerhq/hw-app-btc";
const btc = new Btc(transport)

getWalletPublicKey

Parameters

• path string a BIP 32 path

• opts (boolean | {verify: boolean?, format: AddressFormat?})

• options an object with optional these fields:- verify (boolean) will ask user to confirm the address on the device

  • format ("legacy" | "p2sh" | "bech32") to use different bitcoin address formatter.NB The normal usage is to use:- legacy format with 44' paths

  • p2sh format with 49' paths

  • bech32 format with 173' paths

Examples

btc.getWalletPublicKey("44'/0'/0'/0/0").then(o => o.bitcoinAddress)
btc.getWalletPublicKey("49'/0'/0'/0/0", { format: "p2sh" }).then(o => o.bitcoinAddress)

Returns Promise<{publicKey: string, bitcoinAddress: string, chainCode: string}>

signMessageNew

You can sign a message according to the Bitcoin Signature format and retrieve v, r, s given the message and the BIP 32 path of the account to sign.

Parameters

• path string
• messageHex string

Examples

btc.signMessageNew_async("44'/60'/0'/0'/0", Buffer.from("test").toString("hex")).then(function(result) {
var v = result['v'] + 27 + 4;
var signature = Buffer.from(v.toString(16) + result['r'] + result['s'], 'hex').toString('base64');
console.log("Signature : " + signature);
}).catch(function(ex) {console.log(ex);});

Returns Promise<{v: number, r: string, s: string}>

createPaymentTransactionNew

To sign a transaction involving standard (P2PKH) inputs, call createPaymentTransactionNew with the following parameters

Parameters

• inputs Array<[Transaction, number, string?, number?]> is an array of [ transaction, output_index, optional redeem script, optional sequence ] where- transaction is the previously computed transaction object for this UTXO
  • output_index is the output in the transaction used as input for this UTXO (counting from 0)
  • redeem script is the optional redeem script to use when consuming a Segregated Witness input
  • sequence is the sequence number to use for this input (when using RBF), or non present
• associatedKeysets Array<string> is an array of BIP 32 paths pointing to the path to the private key used for each UTXO
• changePath string is an optional BIP 32 path pointing to the path to the public key used to compute the change address
• outputScriptHex string is the hexadecimal serialized outputs of the transaction to sign
• lockTime number is the optional lockTime of the transaction to sign, or default (0)
• sigHashType number is the hash type of the transaction to sign, or default (all)
• segwit boolean is an optional boolean indicating wether to use segwit or not
• initialTimestamp number is an optional timestamp of the function call to use for coins that necessitate timestamps only, (not the one that the tx will include)
• additionals Array<string> list of additionnal options- "abc" for bch
  • "gold" for btg
  • "bipxxx" for using BIPxxx
  • "sapling" to indicate a zec transaction is supporting sapling (to be set over block 419200)
• expiryHeight Buffer is an optional Buffer for zec overwinter / sapling Txs

Examples

btc.createPaymentTransactionNew(
[ [tx1, 1] ],
["0'/0/0"],
undefined,
"01905f0100000000001976a91472a5d75c8d2d0565b656a5232703b167d50d5a2b88ac"
).then(res => ...);

Returns any the signed transaction ready to be broadcast

signP2SHTransaction

To obtain the signature of multisignature (P2SH) inputs, call signP2SHTransaction_async with the folowing parameters

Parameters

• inputs Array<[Transaction, number, string?, number?]> is an array of [ transaction, output_index, redeem script, optional sequence ] where- transaction is the previously computed transaction object for this UTXO
  • output_index is the output in the transaction used as input for this UTXO (counting from 0)
  • redeem script is the mandatory redeem script associated to the current P2SH input
  • sequence is the sequence number to use for this input (when using RBF), or non present
• associatedKeysets Array<string> is an array of BIP 32 paths pointing to the path to the private key used for each UTXO
• outputScriptHex string is the hexadecimal serialized outputs of the transaction to sign
• lockTime number is the optional lockTime of the transaction to sign, or default (0)
• sigHashType number is the hash type of the transaction to sign, or default (all)
• segwit boolean (optional, default false)
• transactionVersion number (optional, default DEFAULT_VERSION)

Examples

btc.signP2SHTransaction(
[ [tx, 1, "52210289b4a3ad52a919abd2bdd6920d8a6879b1e788c38aa76f0440a6f32a9f1996d02103a3393b1439d1693b063482c04bd40142db97bdf139eedd1b51ffb7070a37eac321030b9a409a1e476b0d5d17b804fcdb81cf30f9b99c6f3ae1178206e08bc500639853ae"] ],
["0'/0/0"],
"01905f0100000000001976a91472a5d75c8d2d0565b656a5232703b167d50d5a2b88ac"
).then(result => ...);

Returns any the signed transaction ready to be broadcast

splitTransaction

For each UTXO included in your transaction, create a transaction object from the raw serialized version of the transaction used in this UTXO.

Parameters

• transactionHex string
• isSegwitSupported boolean? (optional, default false)
• hasTimestamp boolean (optional, default false)
• hasExtraData boolean (optional, default false)
• additionals Array<string> (optional, default [])

Examples

const tx1 = btc.splitTransaction("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");

Returns Transaction

serializeTransactionOutputs

Parameters

• $0 any
  • $0.outputs

Examples

const tx1 = btc.splitTransaction("01000000014ea60aeac5252c14291d428915bd7ccd1bfc4af009f4d4dc57ae597ed0420b71010000008a47304402201f36a12c240dbf9e566bc04321050b1984cd6eaf6caee8f02bb0bfec08e3354b022012ee2aeadcbbfd1e92959f57c15c1c6debb757b798451b104665aa3010569b49014104090b15bde569386734abf2a2b99f9ca6a50656627e77de663ca7325702769986cf26cc9dd7fdea0af432c8e2becc867c932e1b9dd742f2a108997c2252e2bdebffffffff0281b72e00000000001976a91472a5d75c8d2d0565b656a5232703b167d50d5a2b88aca0860100000000001976a9144533f5fb9b4817f713c48f0bfe96b9f50c476c9b88ac00000000");
const outputScript = btc.serializeTransactionOutputs(tx1).toString('hex');

Returns Buffer

serializeTransaction

Parameters

• transaction Transaction
• skipWitness boolean
• timestamp Buffer
• additionals Array<string> (optional, default [])

displayTransactionDebug

Parameters

• transaction Transaction

TransactionInput

Type: {prevout: Buffer, script: Buffer, sequence: Buffer, tree: Buffer?}

Properties

• prevout Buffer
• script Buffer
• sequence Buffer
• tree Buffer?

TransactionOutput

Type: {amount: Buffer, script: Buffer}

Properties

• amount Buffer
• script Buffer

Transaction

Type: {version: Buffer, inputs: Array<TransactionInput>, outputs: Array<TransactionOutput>?, locktime: Buffer?, witness: Buffer?, timestamp: Buffer?, nVersionGroupId: Buffer?, nExpiryHeight: Buffer?, extraData: Buffer?}

Properties

• version Buffer
• inputs Array<TransactionInput>
• outputs Array<TransactionOutput>?
• locktime Buffer?
• witness Buffer?
• timestamp Buffer?
• nVersionGroupId Buffer?
• nExpiryHeight Buffer?
• extraData Buffer?