0.5.4: compound hash

src/commonMain/kotlin/net/sergeych/crypto2/Hash.kt

@@ -21,21 +21,24 @@ private interface StreamProcessor {
  * - [ofFlow] to calculate hash of the data in the [Flow<UByteArray>]
  */
 @Suppress("unused")
-enum class Hash(private val direct: ((UByteArray) -> UByteArray)? = null,private val streamProcessor: () -> StreamProcessor) {
+enum class Hash(
+    private val direct: ((UByteArray) -> UByteArray)? = null,
+    private val streamProcessor: () -> StreamProcessor,
+) {
 
     Blake2b(
         // direct blacke2 is faster than stream:
         { GenericHash.genericHash(it) }, {
-        object : StreamProcessor {
-            val state = GenericHash.genericHashInit()
-            override fun update(data: UByteArray) {
-                GenericHash.genericHashUpdate(state, data)
-            }
+            object : StreamProcessor {
+                val state = GenericHash.genericHashInit()
+                override fun update(data: UByteArray) {
+                    GenericHash.genericHashUpdate(state, data)
+                }
 
-            override fun final(): UByteArray =
-                GenericHash.genericHashFinal(state)
-        }
-    }),
+                override fun final(): UByteArray =
+                    GenericHash.genericHashFinal(state)
+            }
+        }),
     Sha3_384(
         // direct Keccaak currently is slower
         null,
@@ -59,6 +62,24 @@ enum class Hash(private val direct: ((UByteArray) -> UByteArray)? = null,private
 
                 override fun final(): UByteArray = state.digest().asUByteArray()
             }
+        }),
+
+    /**
+     * Synthetic hash contains of [Blake2b] and [Sha3_384] hashes concatenated in this order. Let calculate
+     * compound hash using [ofFlow] or [ofChannel] effectively.
+     */
+    Sha3AndBlake(null,
+        {
+            object : StreamProcessor {
+                val blake = Blake2b.streamProcessor()
+                val sha384 = Sha3_384.streamProcessor()
+                override fun update(data: UByteArray) {
+                    blake.update(data)
+                    sha384.update(data)
+                }
+
+                override fun final(): UByteArray = blake.final() + sha384.final()
+            }
         });
 
     @Deprecated("will be removed in favor of digest()", ReplaceWith("digest()"))
@@ -69,7 +90,7 @@ enum class Hash(private val direct: ((UByteArray) -> UByteArray)? = null,private
      * @param src data to calculate hash digest over
      * @return calculated hash value
      */
-    fun digest(src: UByteArray): UByteArray = direct?.invoke(src) ?: streamProcessor().also { it.update(src)}.final()
+    fun digest(src: UByteArray): UByteArray = direct?.invoke(src) ?: streamProcessor().also { it.update(src) }.final()
 
     /**
      * Collect the flow and return the hash digest of all the data. Let calculate hashes on data
@@ -87,7 +108,7 @@ enum class Hash(private val direct: ((UByteArray) -> UByteArray)? = null,private
      */
     suspend fun ofChannel(source: ReceiveChannel<UByteArray>): UByteArray {
         val sp = streamProcessor()
-        for( block in source) sp.update(block)
+        for (block in source) sp.update(block)
         return sp.final()
     }
 
@@ -106,7 +127,7 @@ fun blake2b(src: UByteArray): UByteArray = Hash.Blake2b.digest(src)
  * brute force.collision attack than just [blake2b]. Note that different suffixes provide different
  * results.
  */
-fun blake2b2l(src: UByteArray,suffix: UByteArray = defaultSuffix1): UByteArray =
+fun blake2b2l(src: UByteArray, suffix: UByteArray = defaultSuffix1): UByteArray =
     blake2b(blake2b(src) + suffix + src)
 
 /**