From decc1ab91ff4f033cbf0754dd176593d39892c4d Mon Sep 17 00:00:00 2001
From: Ugljesa Jovanovic <ugljesa.jovanovic@ionspin.com>
Date: Wed, 8 Jan 2020 21:13:41 +0100
Subject: [PATCH] Started work on argon2 implementation

---
 buildSrc/src/main/kotlin/Deps.kt              |  2 +-
 .../kotlin/com/ionspin/kotlin/crypto/Util.kt  | 19 +++++
 .../kotlin/crypto/keyderivation/Argon2.kt     | 74 +++++++++++++++++++
 3 files changed, 94 insertions(+), 1 deletion(-)
 create mode 100644 multiplatform-crypto/src/commonMain/kotlin/com/ionspin/kotlin/crypto/keyderivation/Argon2.kt

diff --git a/buildSrc/src/main/kotlin/Deps.kt b/buildSrc/src/main/kotlin/Deps.kt
index 432d57a..a1d1631 100644
--- a/buildSrc/src/main/kotlin/Deps.kt
+++ b/buildSrc/src/main/kotlin/Deps.kt
@@ -21,7 +21,7 @@ object Versions {
     val nodePlugin = "1.3.0"
     val dokkaPlugin = "0.9.18"
 
-    val kotlinBigNumVersion = "0.1.5-SNAPSHOT"
+    val kotlinBigNumVersion = "0.1.6-SNAPSHOT"
 
 
 }
diff --git a/multiplatform-crypto/src/commonMain/kotlin/com/ionspin/kotlin/crypto/Util.kt b/multiplatform-crypto/src/commonMain/kotlin/com/ionspin/kotlin/crypto/Util.kt
index 1b222ce..81c47b8 100644
--- a/multiplatform-crypto/src/commonMain/kotlin/com/ionspin/kotlin/crypto/Util.kt
+++ b/multiplatform-crypto/src/commonMain/kotlin/com/ionspin/kotlin/crypto/Util.kt
@@ -87,4 +87,23 @@ fun Array<UByte>.toHexString() : String {
             it.toString(16)
         }
     }
+}
+
+// UInt / Array utils
+@ExperimentalUnsignedTypes
+fun UInt.toBigEndianUByteArray() : Array<UByte> {
+    return Array<UByte> (4) {
+        ((this shr (24 - (it * 8))) and 0xFFU).toUByte()
+    }
+}
+@ExperimentalUnsignedTypes
+fun UInt.toLittleEndianUByteArray() : Array<UByte> {
+    return Array<UByte> (4) {
+        ((this shr (it * 8)) and 0xFFU).toUByte()
+    }
+}
+
+@ExperimentalUnsignedTypes
+operator fun UInt.plus(other : Array<UByte>) : Array<UByte> {
+    return this.toLittleEndianUByteArray() + other
 }
\ No newline at end of file
diff --git a/multiplatform-crypto/src/commonMain/kotlin/com/ionspin/kotlin/crypto/keyderivation/Argon2.kt b/multiplatform-crypto/src/commonMain/kotlin/com/ionspin/kotlin/crypto/keyderivation/Argon2.kt
new file mode 100644
index 0000000..9cacd68
--- /dev/null
+++ b/multiplatform-crypto/src/commonMain/kotlin/com/ionspin/kotlin/crypto/keyderivation/Argon2.kt
@@ -0,0 +1,74 @@
+/*
+ *    Copyright 2019 Ugljesa Jovanovic
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+
+package com.ionspin.kotlin.crypto.keyderivation
+
+import com.ionspin.kotlin.crypto.chunked
+import com.ionspin.kotlin.crypto.hash.blake2b.Blake2b
+import com.ionspin.kotlin.crypto.plus
+
+/**
+ * Created by Ugljesa Jovanovic
+ * ugljesa.jovanovic@ionspin.com
+ * on 08-Jan-2020
+ */
+@ExperimentalUnsignedTypes
+class Argon2 internal constructor(
+    val password : Array<UByte>,
+    val salt : Array<UByte>,
+    val parallelism : UInt,
+    val tagLength : UInt,
+    val memorySize : UInt,
+    val numberOfIterations : UInt,
+    val versionNumber : UInt,
+    val key : Array<UByte>,
+    val type : ArgonType
+){
+    enum class ArgonType {
+        Argon2i, Argon2d, Argon2id
+    }
+    companion object {
+
+
+        fun hash(input : Array<UByte>, length : UInt) : Array<UByte> {
+            if (length <= 64U) {
+                return Blake2b.digest(length + input)
+            }
+            //We can cast to int because UInt even if MAX_VALUE divided by 32 is guaranteed not to overflow
+            val numberOfBlocks = (1U + ((length - 1U) / 32U) - 1U).toInt() // equivalent  to ceil(length/32) - 1
+            val v = Array<Array<UByte>>(numberOfBlocks) { emptyArray() }
+            v[0] = Blake2b.digest(length + input)
+            for (i in 1 until numberOfBlocks - 1) {
+                v[i] = Blake2b.digest(v[i-1])
+            }
+            val remainingPartOfInput = input.copyOfRange(input.size - numberOfBlocks * 32, input.size)
+            v[numberOfBlocks] = Blake2b.digest(remainingPartOfInput, hashLength = remainingPartOfInput.size)
+            v.chunked(8)
+
+
+
+            return emptyArray()
+        }
+
+    }
+
+
+
+
+
+
+
+}
\ No newline at end of file