Refactors secure random to extension class

quartz/src/main/java/com/vitorpamplona/quartz/crypto/CryptoUtils.kt

@@ -45,19 +45,15 @@ object CryptoUtils {
         nip44.clearCache()
     }
 
-    fun randomInt(bound: Int): Int = random.nextInt(bound)
-
-    fun random(size: Int): ByteArray {
-        val bytes = ByteArray(size)
-        random.nextBytes(bytes)
-        return bytes
-    }
-
     /** Provides a 32B "private key" aka random number */
     fun privkeyCreate() = nip01.privkeyCreate()
 
     fun pubkeyCreate(privKey: ByteArray) = nip01.pubkeyCreate(privKey)
 
+    fun randomInt(bound: Int) = random.nextInt(bound)
+
+    fun random(size: Int) = random.nextBytes(size)
+
     fun signString(
         message: String,
         privKey: ByteArray,

quartz/src/main/java/com/vitorpamplona/quartz/crypto/RandomExt.kt

@@ -0,0 +1,25 @@
+/**
+ * Copyright (c) 2024 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.crypto
+
+import java.security.SecureRandom
+
+fun SecureRandom.nextBytes(size: Int) = ByteArray(size).also { nextBytes(it) }

quartz/src/main/java/com/vitorpamplona/quartz/crypto/nip01/Nip01.kt

@@ -21,7 +21,7 @@
 package com.vitorpamplona.quartz.crypto.nip01
 
 import com.vitorpamplona.quartz.crypto.CryptoUtils
-import com.vitorpamplona.quartz.crypto.CryptoUtils.random
+import com.vitorpamplona.quartz.crypto.nextBytes
 import fr.acinq.secp256k1.Secp256k1
 import java.security.MessageDigest
 import java.security.SecureRandom
@@ -31,7 +31,7 @@ class Nip01(
     val random: SecureRandom,
 ) {
     /** Provides a 32B "private key" aka random number */
-    fun privkeyCreate() = random(32)
+    fun privkeyCreate() = random.nextBytes(32)
 
     fun compressedPubkeyCreate(privKey: ByteArray) = secp256k1.pubKeyCompress(secp256k1.pubkeyCreate(privKey))
 
@@ -40,7 +40,7 @@ class Nip01(
     fun sign(
         data: ByteArray,
         privKey: ByteArray,
-        auxrand32: ByteArray? = random(32),
+        auxrand32: ByteArray? = random.nextBytes(32),
     ): ByteArray = secp256k1.signSchnorr(data, privKey, auxrand32)
 
     fun signDeterministic(
@@ -62,6 +62,6 @@ class Nip01(
     fun signString(
         message: String,
         privKey: ByteArray,
-        auxrand32: ByteArray = random(32),
+        auxrand32: ByteArray = random.nextBytes(32),
     ): ByteArray = sign(CryptoUtils.sha256(message.toByteArray()), privKey, auxrand32)
 }