Files
hash.kt/src/commonMain/kotlin/com/infendro/hash/blake2/Blake2s.kt
2026-03-11 21:58:51 +01:00

128 lines
3.9 KiB
Kotlin

package com.infendro.hash.blake2
import com.infendro.bytes.ByteOrder.LITTLE_ENDIAN
import com.infendro.bytes.bytearray.copyInto
import com.infendro.bytes.intarray.toByteArray
import com.infendro.hash.HashFunction
class Blake2s(bytes: Int) : HashFunction(bytes, 64) {
init {
require(bytes in 1..32)
}
private val h = initial.copyOf()
.also { h ->
h[0] = h[0] xor (0x01010000 or bytes)
}
private val m = IntArray(16)
private val v = IntArray(16)
override fun reset() {
super.reset()
initial.copyInto(h)
h[0] = h[0] xor (0x01010000 or bytes)
}
override fun update(byte: Byte) {
if (buffer.isFull()) {
process()
buffer.reset()
}
buffer.append(byte)
length++
}
override fun update(bytes: ByteArray) {
if (buffer.isFull() && bytes.isNotEmpty()) {
process()
buffer.reset()
}
var i = 0
var free = buffer.free
while (i + free < bytes.size) {
buffer.append(bytes, startIndex = i, endIndex = i + free)
length += free
process()
buffer.reset()
free = buffer.free
i += block
}
buffer.append(bytes, startIndex = i)
length += (bytes.size - i)
}
override fun process() = compress(buffer.value, length, false)
private fun finalize() = compress(buffer.value, length, true)
override fun digestInto(destination: ByteArray, destinationOffset: Int) {
finalize()
h.toByteArray(order = LITTLE_ENDIAN).copyInto(destination, destinationOffset, endIndex = bytes)
reset()
}
private fun compress(block: ByteArray, t: Long, last: Boolean) {
block.copyInto(m)
for (i in 0..<8) v[i] = h[i]
for (i in 0..<8) v[i + 8] = initial[i]
v[12] = v[12] xor t.toInt()
v[13] = v[13] xor (t ushr 32).toInt()
if (last) v[14] = v[14].inv()
repeat(10) { r ->
val s = sigma[r]
mix(v, 0, 4, 8, 12, m[s[0]], m[s[1]])
mix(v, 1, 5, 9, 13, m[s[2]], m[s[3]])
mix(v, 2, 6, 10, 14, m[s[4]], m[s[5]])
mix(v, 3, 7, 11, 15, m[s[6]], m[s[7]])
mix(v, 0, 5, 10, 15, m[s[8]], m[s[9]])
mix(v, 1, 6, 11, 12, m[s[10]], m[s[11]])
mix(v, 2, 7, 8, 13, m[s[12]], m[s[13]])
mix(v, 3, 4, 9, 14, m[s[14]], m[s[15]])
}
for (i in 0..<8) {
h[i] = h[i] xor v[i] xor v[i + 8]
}
}
private fun mix(v: IntArray, a: Int, b: Int, c: Int, d: Int, x: Int, y: Int) {
v[a] += v[b] + x
v[d] = (v[d] xor v[a]).rotateRight(16)
v[c] += v[d]
v[b] = (v[b] xor v[c]).rotateRight(12)
v[a] += v[b] + y
v[d] = (v[d] xor v[a]).rotateRight(8)
v[c] += v[d]
v[b] = (v[b] xor v[c]).rotateRight(7)
}
companion object {
private val initial = intArrayOf(
+0x6a09e667, -0x4498517b,
+0x3c6ef372, -0x5ab00ac6,
+0x510e527f, -0x64fa9774,
+0x1f83d9ab, +0x5be0cd19,
)
private val sigma = arrayOf(
intArrayOf(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15),
intArrayOf(14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3),
intArrayOf(11, 8, 12, 0, 5, 2, 15, 13, 10, 14, 3, 6, 7, 1, 9, 4),
intArrayOf(7, 9, 3, 1, 13, 12, 11, 14, 2, 6, 5, 10, 4, 0, 15, 8),
intArrayOf(9, 0, 5, 7, 2, 4, 10, 15, 14, 1, 11, 12, 6, 8, 3, 13),
intArrayOf(2, 12, 6, 10, 0, 11, 8, 3, 4, 13, 7, 5, 15, 14, 1, 9),
intArrayOf(12, 5, 1, 15, 14, 13, 4, 10, 0, 7, 6, 3, 9, 2, 8, 11),
intArrayOf(13, 11, 7, 14, 12, 1, 3, 9, 5, 0, 15, 4, 8, 6, 2, 10),
intArrayOf(6, 15, 14, 9, 11, 3, 0, 8, 12, 2, 13, 7, 1, 4, 10, 5),
intArrayOf(10, 2, 8, 4, 7, 6, 1, 5, 15, 11, 9, 14, 3, 12, 13, 0),
)
}
}