remove unsigned support

src/commonMain/kotlin/com/infendro/hash/keccak/Keccak.kt

@@ -19,14 +19,14 @@ open class Keccak(
     override val block: Int
         get() = rate
 
-    private val rc = ulongArrayOf(
-        0x0000000000000001UL, 0x0000000000008082UL, 0x800000000000808aUL, 0x8000000080008000UL,
-        0x000000000000808bUL, 0x0000000080000001UL, 0x8000000080008081UL, 0x8000000000008009UL,
-        0x000000000000008aUL, 0x0000000000000088UL, 0x0000000080008009UL, 0x000000008000000aUL,
-        0x000000008000808bUL, 0x800000000000008bUL, 0x8000000000008089UL, 0x8000000000008003UL,
-        0x8000000000008002UL, 0x8000000000000080UL, 0x000000000000800aUL, 0x800000008000000aUL,
-        0x8000000080008081UL, 0x8000000000008080UL, 0x0000000080000001UL, 0x8000000080008008UL,
-    ).asLongArray()
+    private val rc = longArrayOf(
+        +0x0000000000000001L, +0x0000000000008082L, -0x7fffffffffff7f76L, -0x7fffffff7fff8000L,
+        +0x000000000000808bL, +0x0000000080000001L, -0x7fffffff7fff7f7fL, -0x7fffffffffff7ff7L,
+        +0x000000000000008aL, +0x0000000000000088L, +0x0000000080008009L, +0x000000008000000aL,
+        +0x000000008000808bL, -0x7fffffffffffff75L, -0x7fffffffffff7f77L, -0x7fffffffffff7ffdL,
+        -0x7fffffffffff7ffeL, -0x7fffffffffffff80L, +0x000000000000800aL, -0x7fffffff7ffffff6L,
+        -0x7fffffff7fff7f7fL, -0x7fffffffffff7f80L, +0x0000000080000001L, -0x7fffffff7fff7ff8L,
+    )
 
     private val rotation = arrayOf(
         intArrayOf(0, 36, 3, 41, 18),
@@ -39,16 +39,13 @@ open class Keccak(
     override fun hashInto(value: ByteArray, destination: ByteArray, destinationOffset: Int) {
         val input = pad(value)
         val state = LongArray(25)
-        val w = LongArray(block / 8)
-        val b = LongArray(25)
-        val c = LongArray(5)
-        val d = LongArray(5)
 
         for (i in input.indices step block) {
-            absorb(state, input, i, w)
-            permute(state, b, c, d)
+            val block = input.sliceArray(i..<(i + block))
+            absorb(state, block)
+            permute(state)
         }
-        squeeze(state, b, c, d, destination, destinationOffset)
+        squeeze(state, destination, destinationOffset)
     }
 
     private fun pad(value: ByteArray): ByteArray {
@@ -60,21 +57,15 @@ open class Keccak(
         }
     }
 
-    private fun absorb(state: LongArray, value: ByteArray, offset: Int, w: LongArray) {
-        value.copyInto(w, startIndex = offset, endIndex = offset + block, order = LITTLE_ENDIAN)
+    private fun absorb(state: LongArray, block: ByteArray) {
+        val w = LongArray(this.block / 8)
+        block.copyInto(w, order = LITTLE_ENDIAN)
         for (i in w.indices) {
             state[i] = state[i] xor w[i]
         }
     }
 
-    private fun squeeze(
-        state: LongArray,
-        b: LongArray,
-        c: LongArray,
-        d: LongArray,
-        destination: ByteArray,
-        destinationOffset: Int,
-    ) {
+    private fun squeeze(state: LongArray, destination: ByteArray, destinationOffset: Int) {
         val buffer = ByteArray(8)
         val threshold = rate / 8
 
@@ -82,7 +73,7 @@ open class Keccak(
         var i = 0
         while (consumed < bytes) {
             if (i == threshold) {
-                permute(state, b, c, d)
+                permute(state)
                 i = 0
             }
 
@@ -95,7 +86,11 @@ open class Keccak(
         }
     }
 
-    private fun permute(a: LongArray, b: LongArray, c: LongArray, d: LongArray) = repeat(24) { round ->
+    private fun permute(a: LongArray) = repeat(24) { round ->
+        val b = LongArray(25)
+        val c = LongArray(5)
+        val d = LongArray(5)
+
         // θ
         for (x in 0..4) {
             c[x] = a[x] xor a[x + 5] xor a[x + 10] xor a[x + 15] xor a[x + 20]

src/commonMain/kotlin/com/infendro/hash/keccak/shake/SHAKE128.kt

@@ -2,6 +2,4 @@ package com.infendro.hash.keccak.shake
 
 import com.infendro.hash.keccak.Keccak
 
-class SHAKE128(
-    bytes: Int,
-) : Keccak(bytes, 168, 0x1F)
+class SHAKE128(bytes: Int) : Keccak(bytes, 168, 0x1F)

src/commonMain/kotlin/com/infendro/hash/keccak/shake/SHAKE256.kt

@@ -2,6 +2,4 @@ package com.infendro.hash.keccak.shake
 
 import com.infendro.hash.keccak.Keccak
 
-class SHAKE256(
-    bytes: Int,
-) : Keccak(bytes, 136, 0x1F)
+class SHAKE256(bytes: Int) : Keccak(bytes, 136, 0x1F)