mirror of
https://github.com/bitcoin-s/bitcoin-s.git
synced 2025-03-01 01:31:35 +01:00
65 lines
3 KiB
Markdown
65 lines
3 KiB
Markdown
|
---
|
||
|
id: version-1.9.6-sign
|
||
|
title: Sign API
|
||
|
original_id: sign
|
||
|
---
|
||
|
|
||
|
### The [`Sign` API](/api/org/bitcoins/crypto/Sign)
|
||
|
|
||
|
This is the API we define to sign things with. It takes in an arbitrary byte vector and returns a `Future[ECDigitalSignature]`. The reason we incorporate `Future`s here is for extensibility of this API. We would like to provide implementations of this API for hardware devices, which need to be asynchrnous since they may require user input.
|
||
|
|
||
|
From [Sign.scala](/api/org/bitcoins/crypto/Sign):
|
||
|
|
||
|
```scala
|
||
|
import scodec.bits._
|
||
|
import org.bitcoins.crypto._
|
||
|
import scala.concurrent._
|
||
|
import scala.concurrent.duration._
|
||
|
|
||
|
trait Sign {
|
||
|
def signFunction: ByteVector => Future[ECDigitalSignature]
|
||
|
|
||
|
def signFuture(bytes: ByteVector): Future[ECDigitalSignature] =
|
||
|
signFunction(bytes)
|
||
|
|
||
|
def sign(bytes: ByteVector): ECDigitalSignature = {
|
||
|
Await.result(signFuture(bytes), 30.seconds)
|
||
|
}
|
||
|
|
||
|
def publicKey: ECPublicKey
|
||
|
}
|
||
|
```
|
||
|
|
||
|
The `ByteVector` that is input to the `signFunction` should be the hash that is output from [`TransactionSignatureSerializer`](/api/org/bitcoins/core/crypto/TransactionSignatureSerializer)'s `hashForSignature` method. Our in-memory [`BaseECKey`](/api/org/bitcoins/crypto/BaseECKey) types implement the `Sign` API.
|
||
|
|
||
|
If you wanted to implement a new `Sign` api for a hardware wallet, you can easily pass it into the `TxBuilder`/`Signer` classes to allow for you to use those devices to sign with Bitcoin-S.
|
||
|
|
||
|
This API is currently used to sign ordinary transactions with our [`Signer`](/api/org/bitcoins/core/wallet/signer/Signer)s. The `Signer` subtypes (i.e. `P2PKHSigner`) implement the specific functionality needed to produce a valid digital signature for their corresponding script type.
|
||
|
|
||
|
|
||
|
### The [`ExtSign`](/api/org/bitcoins/crypto/Sign) API.
|
||
|
|
||
|
An [ExtKey](/api/org/bitcoins/core/crypto/ExtKey) is a data structure that can be used to generate more keys from a parent key. For more information look at [hd-keys.md](../core/hd-keys.md)
|
||
|
|
||
|
You can sign with `ExtPrivateKey` the same way you could with a normal `ECPrivateKey`.
|
||
|
|
||
|
```scala
|
||
|
import org.bitcoins.core.hd._
|
||
|
import org.bitcoins.core.crypto._
|
||
|
|
||
|
val extPrivKey = ExtPrivateKey(ExtKeyVersion.SegWitMainNetPriv)
|
||
|
// extPrivKey: ExtPrivateKey = Masked(ExtPrivateKeyImpl)
|
||
|
|
||
|
extPrivKey.sign(DoubleSha256Digest.empty.bytes)
|
||
|
// res0: ECDigitalSignature = ECDigitalSignature(3045022100c81a3e2a65ada4ea00cde9cf1618ebcda9f8b40ef4bf2a8f8b6b46a70dec008f022048a628634602e51301b2a0fc9ddb5504a642bf464bb806b51bf90de2e3dc665e)
|
||
|
|
||
|
val path = BIP32Path(Vector(BIP32Node(0,false)))
|
||
|
// path: BIP32Path = m/0
|
||
|
|
||
|
extPrivKey.sign(DoubleSha256Digest.empty.bytes,path)
|
||
|
// res1: ECDigitalSignature = ECDigitalSignature(304402205f7826826b5d4eb3373b5a62dc68320bcba5677d38b40005bf64e396778726e302200b949cbceaed378e6c53663f00591046e23489bca2835fa31544262c86bda4d1)
|
||
|
```
|
||
|
|
||
|
With `ExtSign`, you can use `ExtPrivateKey` to sign transactions inside of `TxBuilder` since `UTXOSpendingInfo` takes in `Sign` as a parameter.
|
||
|
|
||
|
You can also provide a `path` to use to derive a child `ExtPrivateKey`, and then sign with that child private key
|