Implement streaming API

src/commonMain/kotlin/com/infendro/hash/sha2/SHA-384.kt

@@ -1,30 +1,79 @@
 package com.infendro.hash.sha2
 
+import com.infendro.bytes.bytearray.copyInto
 import com.infendro.bytes.longarray.copyInto
 import com.infendro.hash.HashFunction
+import com.infendro.hash.sha2.`SHA-512`.Companion.c
 
-object `SHA-384` : HashFunction {
-    override val bytes: Int
-        get() = 48
+class `SHA-384` : HashFunction(48, 128) {
+    private val h = initial.copyOf()
 
-    override val block: Int
-        get() = 128
+    private val w = LongArray(80)
+    private val v = LongArray(8)
 
-    private val initial = longArrayOf(
-        -0x344462a23efa6128, +0x629a292a367cd507,
-        -0x6ea6fea5cf8f22e9, +0x152fecd8f70e5939,
-        +0x67332667ffc00b31, -0x714bb57897a7eaef,
-        -0x24f3d1f29b067059, +0x47b5481dbefa4fa4,
-    )
+    override fun reset() {
+        super.reset()
+        initial.copyInto(h)
+    }
 
-    override fun hashInto(value: ByteArray, destination: ByteArray, destinationOffset: Int) {
-        val input = `SHA-512`.pad(value)
-        val h = initial.copyOf()
+    override fun process() = process(buffer.value)
 
-        for (i in input.indices step block) {
-            val block = input.sliceArray(i..<(i + block))
-            `SHA-512`.process(h, block)
+    private fun finalize() {
+        buffer.append(0x80.toByte())
+        if (buffer.free < 16) {
+            process(buffer.value)
+            buffer.reset()
         }
+        buffer.jumpTo(112)
+        buffer.append(length * 8)
+
+        process(buffer.value)
+    }
+
+    override fun digestInto(destination: ByteArray, destinationOffset: Int) {
+        finalize()
         h.copyInto(destination, destinationOffset, endIndex = 6)
+        reset()
+    }
+
+    private fun process(block: ByteArray) {
+        block.copyInto(w)
+        for (i in 16..<80) {
+            val s0 = w[i - 15].rotateRight(1) xor w[i - 15].rotateRight(8) xor (w[i - 15] ushr 7)
+            val s1 = w[i - 2].rotateRight(19) xor w[i - 2].rotateRight(61) xor (w[i - 2] ushr 6)
+            w[i] = (w[i - 16] + s0 + w[i - 7] + s1)
+        }
+        h.copyInto(v)
+
+        repeat(80) { i ->
+            val s0 = v[0].rotateRight(28) xor v[0].rotateRight(34) xor v[0].rotateRight(39)
+            val s1 = v[4].rotateRight(14) xor v[4].rotateRight(18) xor v[4].rotateRight(41)
+            val ch = (v[4] and v[5]) xor (v[4].inv() and v[6])
+            val temp1 = v[7] + s1 + ch + c[i] + w[i]
+            val maj = (v[0] and v[1]) xor (v[0] and v[2]) xor (v[1] and v[2])
+            val temp2 = s0 + maj
+
+            v[7] = v[6]
+            v[6] = v[5]
+            v[5] = v[4]
+            v[4] = v[3] + temp1
+            v[3] = v[2]
+            v[2] = v[1]
+            v[1] = v[0]
+            v[0] = temp1 + temp2
+        }
+
+        for (i in 0..<8) {
+            h[i] += v[i]
+        }
+    }
+
+    companion object {
+        private val initial = longArrayOf(
+            -0x344462a23efa6128, +0x629a292a367cd507,
+            -0x6ea6fea5cf8f22e9, +0x152fecd8f70e5939,
+            +0x67332667ffc00b31, -0x714bb57897a7eaef,
+            -0x24f3d1f29b067059, +0x47b5481dbefa4fa4,
+        )
     }
 }