unify code with elliptic.js more

Author: ChALkeR

lib/noble.js

@@ -11,6 +11,14 @@ if (!secp256k1.utils.sha256Sync) {
   secp256k1.utils.sha256Sync = (...msgs) => sha256(secp256k1.utils.concatBytes(...msgs))
 }
 
+function readPublicKey (pubkey) {
+  try {
+    return secp256k1.Point.fromHex(pubkey)
+  } catch (err) {
+    return undefined
+  }
+}
+
 function writePublicKey (output, point) {
   const buf = point.toRawBytes(output.length === 33)
   if (output.length !== buf.length) return 1
@@ -76,11 +84,8 @@ module.exports = {
   },
 
   publicKeyVerify (pubkey) {
-    try {
-      return secp256k1.Point.fromHex(pubkey) ? 0 : 1
-    } catch (err) {
-      return 1
-    }
+    const P = readPublicKey(pubkey)
+    return P ? 0 : 1
   },
 
   publicKeyCreate (output, seckey) {
@@ -95,36 +100,23 @@ module.exports = {
   },
 
   publicKeyConvert (output, pubkey) {
-    try {
-      const publicKey = secp256k1.Point.fromHex(pubkey).toRawBytes(output.length === 33)
-      if (output.length !== publicKey.length) return 1
-      output.set(publicKey)
-      return 0
-    } catch (err) {
-      return 1
-    }
+    const P = readPublicKey(pubkey)
+    if (!P) return 1
+    return writePublicKey(output, P)
   },
 
   publicKeyNegate (output, pubkey) {
-    let P
-    try {
-      P = secp256k1.Point.fromHex(pubkey)
-    } catch (err) {
-      return 1
-    }
-
+    const P = readPublicKey(pubkey)
+    if (!P) return 1
     const point = P.negate()
     return writePublicKey(output, point)
   },
 
   publicKeyCombine (output, pubkeys) {
     const points = new Array(pubkeys.length)
     for (let i = 0; i < pubkeys.length; ++i) {
-      try {
-        points[i] = secp256k1.Point.fromHex(pubkeys[i])
-      } catch (err) {
-        return 1
-      }
+      points[i] = readPublicKey(pubkeys[i])
+      if (!points[i]) return 1
     }
 
     let point = points[0]
@@ -134,12 +126,8 @@ module.exports = {
   },
 
   publicKeyTweakAdd (output, pubkey, tweak) {
-    let P
-    try {
-      P = secp256k1.Point.fromHex(pubkey)
-    } catch (err) {
-      return 1
-    }
+    const P = readPublicKey(pubkey)
+    if (!P) return 1
 
     tweak = toBig(tweak)
     if (tweak >= secp256k1.CURVE.n) return 2
@@ -151,12 +139,8 @@ module.exports = {
   },
 
   publicKeyTweakMul (output, pubkey, tweak) {
-    let P
-    try {
-      P = secp256k1.Point.fromHex(pubkey)
-    } catch (err) {
-      return 1
-    }
+    const P = readPublicKey(pubkey)
+    if (!P) return 1
 
     tweak = toBig(tweak)
     if (tweak >= secp256k1.CURVE.n || tweak === _0n) return 2
@@ -241,14 +225,10 @@ module.exports = {
     }
     if (signature.hasHighS()) return 3
 
-    let pub
-    try {
-      pub = secp256k1.Point.fromHex(pubkey)
-    } catch (err) {
-      return 2
-    }
+    const P = readPublicKey(pubkey)
+    if (!P) return 2
 
-    return secp256k1.verify(sig, msg32, pub) ? 0 : 3
+    return secp256k1.verify(sig, msg32, P) ? 0 : 3
   },
 
   // Complex logic to return correct error codes
@@ -276,18 +256,14 @@ module.exports = {
   },
 
   ecdh (output, pubkey, seckey, data, hashfn, xbuf, ybuf) {
-    let pub
-    try {
-      pub = secp256k1.Point.fromHex(pubkey)
-    } catch (err) {
-      return 1
-    }
+    const P = readPublicKey(pubkey)
+    if (!P) return 1
 
     const compressed = hashfn === undefined
 
     let point
     try {
-      point = secp256k1.getSharedSecret(seckey, pub, compressed)
+      point = secp256k1.getSharedSecret(seckey, P, compressed)
     } catch (err) {
       return 2
     }