message signing – Find out how to confirm {that a} signature was signed by a pubkey? Taproot and BIP0322

If you’re in search of working JavaScript code, I like to recommend bitcoin-sdk-js which helps BIP322 together with taproot handle signing & verification.

Beneath is methods to implement BIP322 signing & verification for p2pkh(legacy), p2wpkh(segwit) and p2tr(taproot).

import * as bitcoin from 'bitcoin-sdk-js'

const keyPair = await bitcoin.pockets.generateKeyPair();
const privkey = keyPair.privateKey;
const pubkey = keyPair.publicKey;
const legacyAddress = await bitcoin.handle.generateAddress(
  pubkey,
  'legacy',
);
const segwitAddress = await bitcoin.handle.generateAddress(
  pubkey,
  'segwit',
);
const tapAddress = await bitcoin.handle.generateAddress(
  (
    await bitcoin.tapscript.getTapTweakedPubkey(
      pubkey.slice(2),
      await bitcoin.tapscript.getTapTweak(pubkey.slice(2)),
    )
  ).tweakedPubKey,
  'taproot',
);
const msg = 'message you need to signal';
// When
const sigLegacy = await bitcoin.crypto.signMessage(
   msg,
   privkey,
   legacyAddress,
);
const sigSegwit = await bitcoin.crypto.signMessage(
  msg,
  privkey,
  segwitAddress,
);
const sigTap = await bitcoin.crypto.signMessage(msg, privkey, tapAddress);
// Then
assert.strictEqual(
  await bitcoin.crypto.verifyMessage(msg, sigLegacy, legacyAddress),
  true,
);
assert.strictEqual(
  await bitcoin.crypto.verifyMessage(msg, sigSegwit, segwitAddress),
  true,
);
assert.strictEqual(
  await bitcoin.crypto.verifyMessage(msg, sigTap, tapAddress),
  true,
);

Disclaimer: I am the proprietor of the library.