RosettaCodeData/Task/MD5-Implementation/Scala/md5-implementation.scala

104 lines
2.8 KiB
Scala

import java.lang.Math
object MD5 {
private val INIT_A = 0x67452301
private val INIT_B = 0xEFCDAB89
private val INIT_C = 0x98BADCFE
private val INIT_D = 0x10325476
private val SHIFT_AMTS = Array(
7, 12, 17, 22,
5, 9, 14, 20,
4, 11, 16, 23,
6, 10, 15, 21
)
private val TABLE_T = Array.tabulate(64)(i => (Math.abs(Math.sin(i + 1)) * (1L << 32)).toLong.toInt)
def computeMD5(message: Array[Byte]): Array[Byte] = {
val messageLenBytes = message.length
val numBlocks = ((messageLenBytes + 8) >>> 6) + 1
val totalLen = numBlocks << 6
val paddingBytes = Array.fill[Byte](totalLen - messageLenBytes)(0)
paddingBytes(0) = 0x80.toByte
var messageLenBits = messageLenBytes.toLong << 3
for (i <- 0 until 8) {
paddingBytes(paddingBytes.length - 8 + i) = messageLenBits.toByte
messageLenBits >>>= 8
}
var a = INIT_A
var b = INIT_B
var c = INIT_C
var d = INIT_D
val buffer = new Array[Int](16)
for (i <- 0 until numBlocks) {
var index = i << 6
for (j <- 0 until 64) {
buffer(j >>> 2) = (((if (index < messageLenBytes) message(index) else paddingBytes(index - messageLenBytes)) << 24) | (buffer(j >>> 2) >>> 8)).toInt
index += 1
}
val originalA = a
val originalB = b
val originalC = c
val originalD = d
for (j <- 0 until 64) {
val div16 = j >>> 4
val bufferIndex = j match {
case j if j < 16 => j
case j if j < 32 => (j * 5 + 1) & 0x0F
case j if j < 48 => (j * 3 + 5) & 0x0F
case j => (j * 7) & 0x0F
}
val f = div16 match {
case 0 => (b & c) | (~b & d)
case 1 => (b & d) | (c & ~d)
case 2 => b ^ c ^ d
case 3 => c ^ (b | ~d)
}
val temp = b + Integer.rotateLeft(a + f + buffer(bufferIndex) + TABLE_T(j), SHIFT_AMTS((div16 << 2) | (j & 3)))
a = d
d = c
c = b
b = temp
}
a += originalA
b += originalB
c += originalC
d += originalD
}
val md5 = new Array[Byte](16)
var count = 0
for (i <- 0 until 4) {
var n = i match {
case 0 => a
case 1 => b
case 2 => c
case 3 => d
}
for (j <- 0 until 4) {
md5(count) = n.toByte
n >>>= 8
count += 1
}
}
md5
}
def toHexString(b: Array[Byte]): String = b.map(byte => f"$byte%02X").mkString
def main(args: Array[String]): Unit = {
val testStrings = Array("", "a", "abc", "message digest", "abcdefghijklmnopqrstuvwxyz", "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789", "12345678901234567890123456789012345678901234567890123456789012345678901234567890")
testStrings.foreach { s =>
println(s"0x${toHexString(computeMD5(s.getBytes))} <== \"$s\"")
}
}
}