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@ledgerhq/hw-app-btc
Ledger Hardware Wallet BTC JavaScript bindings. Also supports many altcoins.
Are you adding Ledger support to your software wallet?
You may be using this package to communicate with the Bitcoin Nano App.
For a smooth and quick integration:
- See the developers’ documentation on the Developer Portal and
- Go on Discord to chat with developer support and the developer community.
API
Table of Contents
Btc
Bitcoin API.
Parameters
Examples
import Btc from "@ledgerhq/hw-app-btc";
const btc = new Btc({ transport, currency: "bitcoin" });
getWalletXpub
Get an XPUB with a ledger device
Parameters
arg
{path: string, xpubVersion: number} derivation parameter* path: a BIP 32 path of the account level. e.g. 84'/0'/0'
- xpubVersion: the XPUBVersion of the coin used. (use @ledgerhq/currencies if needed)
Returns Promise<string> XPUB of the account
getWalletPublicKey
Parameters
-
path
string a BIP 32 path
-
opts
{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" | "bech32m" | "cashaddr") 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 84' paths
-
cashaddr in case of Bitcoin Cash
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}>
signMessage
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
Examples
btc.signMessage("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}>
createPaymentTransaction
To sign a transaction involving standard (P2PKH) inputs, call createTransaction with the following parameters
Parameters
arg
CreateTransactionArginputs
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
is an array of BIP 32 paths pointing to the path to the private key used for each UTXOchangePath
is an optional BIP 32 path pointing to the path to the public key used to compute the change addressoutputScriptHex
is the hexadecimal serialized outputs of the transaction to sign, including leading vararg voutCountlockTime
is the optional lockTime of the transaction to sign, or default (0)sigHashType
is the hash type of the transaction to sign, or default (all)segwit
is an optional boolean indicating wether to use segwit or not. This includes wrapped segwit.initialTimestamp
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
list of additionnal options* "bech32" for spending native segwit outputs
- "bech32m" for spending segwit v1+ outputs
- "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
is an optional Buffer for zec overwinter / sapling TxsuseTrustedInputForSegwit
trust inputs for segwit transactions. If app version >= 1.4.0 this should be true.
Examples
btc.createTransaction({
inputs: [ [tx1, 1] ],
associatedKeysets: ["0'/0/0"],
outputScriptHex: "01905f0100000000001976a91472a5d75c8d2d0565b656a5232703b167d50d5a2b88ac"
}).then(res => ...);
Returns Promise<string> the signed transaction ready to be broadcast
signP2SHTransaction
To obtain the signature of multisignature (P2SH) inputs, call signP2SHTransaction_async with the folowing parameters
Parameters
arg
SignP2SHTransactionArginputs
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
is an array of BIP 32 paths pointing to the path to the private key used for each UTXOoutputScriptHex
is the hexadecimal serialized outputs of the transaction to signlockTime
is the optional lockTime of the transaction to sign, or default (0)sigHashType
is the hash type of the transaction to sign, or default (all)
Examples
btc.signP2SHTransaction({
inputs: [ [tx, 1, "52210289b4a3ad52a919abd2bdd6920d8a6879b1e788c38aa76f0440a6f32a9f1996d02103a3393b1439d1693b063482c04bd40142db97bdf139eedd1b51ffb7070a37eac321030b9a409a1e476b0d5d17b804fcdb81cf30f9b99c6f3ae1178206e08bc500639853ae"] ],
associatedKeysets: ["0'/0/0"],
outputScriptHex: "01905f0100000000001976a91472a5d75c8d2d0565b656a5232703b167d50d5a2b88ac"
}).then(result => ...);
Returns Promise<Array<string>> 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
stringisSegwitSupported
(boolean | null | undefined) (optional, default false
)hasTimestamp
(optional, default false
)hasExtraData
(optional, default false
)additionals
Array<string> (optional, default []
)
Examples
const tx1 = btc.splitTransaction("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");
Returns Transaction
serializeTransactionOutputs
Parameters
Examples
const tx1 = btc.splitTransaction("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");
const outputScript = btc.serializeTransactionOutputs(tx1).toString('hex');
Returns Buffer
BtcNew
This class implements the same interface as BtcOld (formerly
named Btc), but interacts with Bitcoin hardware app version 2+
which uses a totally new APDU protocol. This new
protocol is documented at
https://github.com/LedgerHQ/app-bitcoin-new/blob/master/doc/bitcoin.md
Since the interface must remain compatible with BtcOld, the methods
of this class are quite clunky, because it needs to adapt legacy
input data into the PSBT process. In the future, a new interface should
be developed that exposes PSBT to the outer world, which would render
a much cleaner implementation.
Parameters
getWalletXpub
This is a new method that allow users to get an xpub at a standard path.
Standard paths are described at
https://github.com/LedgerHQ/app-bitcoin-new/blob/master/doc/bitcoin.md#description
This boils down to paths (N=0 for Bitcoin, N=1 for Testnet):
M/44'/N'/x'/**
M/48'/N'/x'/y'/**
M/49'/N'/x'/**
M/84'/N'/x'/**
M/86'/N'/x'/**
The method was added because of added security in the hardware app v2+. The
new hardware app will allow export of any xpub up to and including the
deepest hardened key of standard derivation paths, whereas the old app
would allow export of any key.
This caused an issue for callers of this class, who only had
getWalletPublicKey() to call which means they have to constuct xpub
themselves:
Suppose a user of this class wants to create an account xpub on a standard
path, M/44'/0'/Z'. The user must get the parent key fingerprint (see BIP32)
by requesting the parent key M/44'/0'. The new app won't allow that, because
it only allows exporting deepest level hardened path. So the options are to
allow requesting M/44'/0' from the app, or to add a new function
"getWalletXpub".
We opted for adding a new function, which can greatly simplify client code.
Parameters
Returns Promise<string>
getWalletPublicKey
This method returns a public key, a bitcoin address, and and a chaincode
for a specific derivation path.
Limitation: If the path is not a leaf node of a standard path, the address
will be the empty string "", see this.getWalletAddress() for details.
Parameters
Returns Promise<{publicKey: string, bitcoinAddress: string, chainCode: string}>
createPaymentTransaction
Build and sign a transaction. See Btc.createPaymentTransaction for
details on how to use this method.
This method will convert the legacy arguments, CreateTransactionArg, into
a psbt which is finally signed and finalized, and the extracted fully signed
transaction is returned.
Parameters
Returns Promise<string>
BtcOld
Bitcoin API.
Parameters
Examples
import Btc from "@ledgerhq/hw-app-btc";
const btc = new Btc({ transport, currency: "zcash" });
getWalletPublicKey
Parameters
-
path
string a BIP 32 path
-
opts
{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" | "cashaddr") 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
-
cashaddr in case of Bitcoin Cash
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}>
createPaymentTransaction
To sign a transaction involving standard (P2PKH) inputs, call createTransaction with the following parameters
Parameters
arg
CreateTransactionArginputs
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
is an array of BIP 32 paths pointing to the path to the private key used for each UTXOchangePath
is an optional BIP 32 path pointing to the path to the public key used to compute the change addressoutputScriptHex
is the hexadecimal serialized outputs of the transaction to signlockTime
is the optional lockTime of the transaction to sign, or default (0)sigHashType
is the hash type of the transaction to sign, or default (all)segwit
is an optional boolean indicating wether to use segwit or notinitialTimestamp
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
list of additionnal options* "bech32" for spending native segwit outputs
- "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
is an optional Buffer for zec overwinter / sapling TxsuseTrustedInputForSegwit
trust inputs for segwit transactions
Examples
btc.createTransaction({
inputs: [ [tx1, 1] ],
associatedKeysets: ["0'/0/0"],
outputScriptHex: "01905f0100000000001976a91472a5d75c8d2d0565b656a5232703b167d50d5a2b88ac"
}).then(res => ...);
Returns Promise<string> the signed transaction ready to be broadcast
CreateTransactionArg
Type: {inputs: Array<[Transaction, number, (string | null | undefined), (number | null | undefined)]>, associatedKeysets: Array<string>, changePath: string?, outputScriptHex: string, lockTime: number?, sigHashType: number?, segwit: boolean?, initialTimestamp: number?, additionals: Array<string>, expiryHeight: Buffer?, useTrustedInputForSegwit: boolean?, onDeviceStreaming: function (arg0: {progress: number, total: number, index: number}): void?, onDeviceSignatureRequested: function (): void?, onDeviceSignatureGranted: function (): void?}
Properties
AddressFormat
address format is one of legacy | p2sh | bech32 | cashaddr
Type: ("legacy"
| "p2sh"
| "bech32"
| "bech32m"
| "cashaddr"
)
AccountType
Encapsulates differences between account types, for example p2wpkh,
p2wpkhWrapped, p2tr.
spendingCondition
Generates a scriptPubKey (output script) from a list of public keys. If a
p2sh redeemScript or a p2wsh witnessScript is needed it will also be set on
the returned SpendingCondition.
The pubkeys are expected to be 33 byte ecdsa compressed pubkeys.
Parameters
Returns SpendingCondition
setInput
Populates the psbt with account type-specific data for an input.
Parameters
i
number The index of the input map to populateinputTx
(Buffer | undefined) The full transaction containing the spent output. This may
be omitted for taproot.spentOutput
SpentOutput The amount and spending condition of the spent outputpubkeys
Array<Buffer> The 33 byte ecdsa compressed public keys involved in the inputpathElems
Array<Array<number>> The paths corresponding to the pubkeys, in same order.
Returns void
setOwnOutput
Populates the psbt with account type-specific data for an output. This is typically
done for change outputs and other outputs that goes to the same account as
being spent from.
Parameters
i
number The index of the output map to populatecond
SpendingCondition The spending condition for this outputpubkeys
Array<Buffer> The 33 byte ecdsa compressed public keys involved in this outputpaths
Array<Array<number>> The paths corresponding to the pubkeys, in same order.
Returns void
getDescriptorTemplate
Returns the descriptor template for this account type. Currently only
DefaultDescriptorTemplates are allowed, but that might be changed in the
future. See class WalletPolicy for more information on descriptor
templates.
Returns DefaultDescriptorTemplate
SingleKeyAccount
Extends BaseAccount
Superclass for single signature accounts. This will make sure that the pubkey
arrays and path arrays in the method arguments contains exactly one element
and calls an abstract method to do the actual work.
getTaprootOutputKey
Calculates a taproot output key from an internal key. This output key will be
used as witness program in a taproot output. The internal key is tweaked
according to recommendation in BIP341:
https://github.com/bitcoin/bips/blob/master/bip-0341.mediawiki#cite_ref-22-0
Parameters
internalPubkey
Buffer A 32 byte x-only taproot internal key
Returns Buffer The output key
AppClient
This class encapsulates the APDU protocol documented at
https://github.com/LedgerHQ/app-bitcoin-new/blob/master/doc/bitcoin.md
Parameters
ClientCommandInterpreter
This class will dispatch a client command coming from the hardware device to
the appropriate client command implementation. Those client commands
typically requests data from a merkle tree or merkelized maps.
A ClientCommandInterpreter is prepared by adding the merkle trees and
merkelized maps it should be able to serve to the hardware device. This class
doesn't know anything about the semantics of the data it holds, it just
serves merkle data. It doesn't even know in what context it is being
executed, ie SignPsbt, getWalletAddress, etc.
If the command yelds results to the client, as signPsbt does, the yielded
data will be accessible after the command completed by calling getYielded(),
which will return the yields in the same order as they came in.
Parameters
progressCallback
function (): void
MerkelizedPsbt
Extends PsbtV2
This class merkelizes a PSBTv2, by merkelizing the different
maps of the psbt. This is used during the transaction signing process,
where the hardware app can request specific parts of the psbt from the
client code and be sure that the response data actually belong to the psbt.
The reason for this is the limited amount of memory available to the app,
so it can't always store the full psbt in memory.
The signing process is documented at
https://github.com/LedgerHQ/app-bitcoin-new/blob/master/doc/bitcoin.md#sign_psbt
Parameters
Merkle
This class implements the merkle tree used by Ledger Bitcoin app v2+,
which is documented at
https://github.com/LedgerHQ/app-bitcoin-new/blob/master/doc/merkle.md
Parameters
MerkleMap
This implements "Merkelized Maps", documented at
https://github.com/LedgerHQ/app-bitcoin-new/blob/master/doc/merkle.md#merkleized-maps
A merkelized map consist of two merkle trees, one for the keys of
a map and one for the values of the same map, thus the two merkle
trees have the same shape. The commitment is the number elements
in the map followed by the keys' merkle root followed by the
values' merkle root.
Parameters
keys
Array<Buffer> Sorted list of (unhashed) keysvalues
Array<Buffer> values, in corresponding order as the keys, and of equal length
WalletPolicy
The Bitcon hardware app uses a descriptors-like thing to describe
how to construct output scripts from keys. A "Wallet Policy" consists
of a "Descriptor Template" and a list of "keys". A key is basically
a serialized BIP32 extended public key with some added derivation path
information. This is documented at
https://github.com/LedgerHQ/app-bitcoin-new/blob/master/doc/wallet.md
Parameters
descriptorTemplate
DefaultDescriptorTemplatekey
string
This implements the "Transaction Extractor" role of BIP370 (PSBTv2
https://github.com/bitcoin/bips/blob/master/bip-0370.mediawiki#transaction-extractor). However
the role is partially documented in BIP174 (PSBTv0
https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki#transaction-extractor).
Parameters
Returns Buffer
finalize
This roughly implements the "input finalizer" role of BIP370 (PSBTv2
https://github.com/bitcoin/bips/blob/master/bip-0370.mediawiki). However
the role is documented in BIP174 (PSBTv0
https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki).
Verify that all inputs have a signature, and set inputFinalScriptwitness
and/or inputFinalScriptSig depending on the type of the spent outputs. Clean
fields that aren't useful anymore, partial signatures, redeem script and
derivation paths.
Parameters
psbt
PsbtV2 The psbt with all signatures added as partial sigs, either
through PSBT_IN_PARTIAL_SIG or PSBT_IN_TAP_KEY_SIG
Returns void
clearFinalizedInput
Deletes fields that are no longer neccesary from the psbt.
Note, the spec doesn't say anything about removing ouput fields
like PSBT_OUT_BIP32_DERIVATION_PATH and others, so we keep them
without actually knowing why. I think we should remove them too.
Parameters
writePush
Writes a script push operation to buf, which looks different
depending on the size of the data. See
https://en.bitcoin.it/wiki/Script#Constants
Parameters
buf
BufferWriter the BufferWriter to write todata
Buffer the Buffer to be pushed.
PsbtV2
Implements Partially Signed Bitcoin Transaction version 2, BIP370, as
documented at https://github.com/bitcoin/bips/blob/master/bip-0370.mediawiki
and https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki
A psbt is a data structure that can carry all relevant information about a
transaction through all stages of the signing process. From constructing an
unsigned transaction to extracting the final serialized transaction ready for
broadcast.
This implementation is limited to what's needed in ledgerjs to carry out its
duties, which means that support for features like multisig or taproot script
path spending are not implemented. Specifically, it supports p2pkh,
p2wpkhWrappedInP2sh, p2wpkh and p2tr key path spending.
This class is made purposefully dumb, so it's easy to add support for
complemantary fields as needed in the future.
serializeTransactionOutputs
Parameters
Examples
const tx1 = btc.splitTransaction("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");
const outputScript = btc.serializeTransactionOutputs(tx1).toString('hex');
Returns Buffer
SignP2SHTransactionArg
Type: {inputs: Array<[Transaction, number, (string | null | undefined), (number | null | undefined)]>, associatedKeysets: Array<string>, outputScriptHex: string, lockTime: number?, sigHashType: number?, segwit: boolean?, transactionVersion: number?}
Properties
TransactionInput
TransactionOutput
Transaction