refactor: pass one tweak object

ExodusMovement · Apr 24, 2024 · 0ae7d57 · 0ae7d57
1 parent 1e6c10c
commit 0ae7d57
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Showing 3 changed files with 28 additions and 27 deletions.
diff --git a/features/keychain/module/__tests__/schnorr.test.js b/features/keychain/module/__tests__/schnorr.test.js
@@ -32,12 +32,14 @@ describe('Schnorr signer', () => {
       const secp256k1Signer = create({ getPrivateHDKey })
 
       const publicKey = await secp256k1Signer.getPublicKey({})
-      const tweakHash = tapTweakHash(publicKey)
+      const scalar = tapTweakHash(publicKey)
 
       const result = await secp256k1Signer.signSchnorr({
         data: Buffer.from(fixture.buffer, 'hex'),
-        tweak: true,
-        tweakOptions: { extraEntropy: Buffer.from(fixture.entropy, 'hex'), tweakHash },
+        tweak: {
+          scalar,
+          options: { extraEntropy: Buffer.from(fixture.entropy, 'hex') },
+        },
       })
 
       expect(Buffer.from(result).toString('hex')).toBe(fixture.sig)
@@ -53,13 +55,15 @@ describe('Schnorr signer', () => {
       const secp256k1Signer = create({ getPrivateHDKey })
 
       const publicKey = await secp256k1Signer.getPublicKey({})
-      const tweakHash = tapTweakHash(publicKey)
+      const scalar = tapTweakHash(publicKey)
 
       expect(publicKey.toString('hex')).toBe(fixture.pub)
 
       const tweakedPublicKey = await secp256k1Signer.getPublicKey({
-        tweak: true,
-        tweakOptions: { extraEntropy: Buffer.from(fixture.entropy, 'hex'), tweakHash },
+        tweak: {
+          scalar,
+          options: { extraEntropy: Buffer.from(fixture.entropy, 'hex') },
+        },
       })
       expect(tweakedPublicKey.toString('hex')).toBe(fixture.pub2)
     }

diff --git a/features/keychain/module/crypto/secp256k1.js b/features/keychain/module/crypto/secp256k1.js
@@ -8,9 +8,9 @@ import { tweakPrivateKey, tweakPublicKey } from './tweak'
 const isValidEcOptions = (ecOptions) =>
   !ecOptions || Object.keys(ecOptions).every((key) => ['canonical'].includes(key))
 
-const isValidTweakOptions = (tweakOptions) =>
-  !tweakOptions ||
-  Object.keys(tweakOptions).every((key) => ['tweakHash', 'extraEntropy'].includes(key))
+const isValidTweak = (tweak) =>
+  !tweak ||
+  (tweak.scalar && Object.keys(tweak.options || {}).every((key) => ['extraEntropy'].includes(key)))
 
 export const create = ({ getPrivateHDKey }) => {
   const EC = elliptic.ec
@@ -24,16 +24,16 @@ export const create = ({ getPrivateHDKey }) => {
       const signature = curve.sign(data, privateKey, pick(ecOptions, ['canonical']))
       return enc === 'der' ? Buffer.from(signature.toDER()) : { ...signature }
     },
-    signSchnorr: async ({ seedId, keyId, data, tweak = false, tweakOptions }) => {
-      assert(isValidTweakOptions(tweakOptions), 'signSchnorr: invalid tweak options')
+    signSchnorr: async ({ seedId, keyId, data, tweak }) => {
+      assert(isValidTweak(tweak), 'signSchnorr: invalid tweak data')
       const hdkey = getPrivateHDKey({ seedId, keyId })
-      const privateKey = tweak ? tweakPrivateKey({ hdkey, tweakOptions }) : hdkey.privateKey
-      return ecc.signSchnorr(data, privateKey, tweakOptions?.extraEntropy)
+      const privateKey = tweak ? tweakPrivateKey({ hdkey, scalar: tweak.scalar }) : hdkey.privateKey
+      return ecc.signSchnorr(data, privateKey, tweak?.options?.extraEntropy)
     },
-    getPublicKey: async ({ seedId, keyId, tweak = false, tweakOptions }) => {
-      assert(isValidTweakOptions(tweakOptions), 'getPublicKey: invalid tweak options')
+    getPublicKey: async ({ seedId, keyId, tweak }) => {
+      assert(isValidTweak(tweak), 'getPublicKey: invalid tweak data')
       const hdkey = getPrivateHDKey({ seedId, keyId })
-      return tweak ? tweakPublicKey({ hdkey, tweakOptions }) : hdkey.publicKey
+      return tweak ? tweakPublicKey({ hdkey, scalar: tweak.scalar }) : hdkey.publicKey
     },
   })
 

diff --git a/features/keychain/module/crypto/tweak.js b/features/keychain/module/crypto/tweak.js
@@ -1,22 +1,19 @@
 import assert from 'minimalistic-assert'
 import ecc from '@exodus/bitcoinerlab-secp256k1'
 
-export const tweakPrivateKey = ({ hdkey, tweakOptions = {} }) => {
-  const { publicKey } = hdkey
+export const tweakPrivateKey = ({ hdkey, scalar }) => {
+  const { privateKey, publicKey } = hdkey
+  assert(ecc.isPrivate(privateKey), 'tweakPrivateKey: expected valid private key')
   assert(ecc.isPointCompressed(publicKey), 'tweakPrivateKey: expected compressed public key')
 
-  const { tweakHash } = tweakOptions
-  assert(tweakHash, 'tweakPrivateKey: tweakHash is required')
+  let tweakedPrivateKey = publicKey[0] === 3 ? ecc.privateNegate(privateKey) : privateKey
+  tweakedPrivateKey = Buffer.from(ecc.privateAdd(tweakedPrivateKey, scalar))
 
-  let { privateKey } = hdkey
-  privateKey = publicKey[0] === 3 ? ecc.privateNegate(privateKey) : privateKey
-  privateKey = Buffer.from(ecc.privateAdd(privateKey, tweakHash))
-
-  return privateKey
+  return tweakedPrivateKey
 }
 
-export const tweakPublicKey = ({ hdkey, tweakOptions }) => {
-  const privateKey = tweakPrivateKey({ hdkey, tweakOptions })
+export const tweakPublicKey = ({ hdkey, scalar }) => {
+  const privateKey = tweakPrivateKey({ hdkey, scalar })
 
   return Buffer.from(ecc.pointFromScalar(privateKey, true))
 }