1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
|
/*
* This file is part of GNU Taler
* (C) 2020 Taler Systems S.A.
*
* GNU Taler is free software; you can redistribute it and/or modify it under the
* terms of the GNU General Public License as published by the Free Software
* Foundation; either version 3, or (at your option) any later version.
*
* GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
* A PARTICULAR PURPOSE. See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along with
* GNU Taler; see the file COPYING. If not, see <http://www.gnu.org/licenses/>
*/
package net.taler.wallet.kotlin.crypto
import net.taler.wallet.kotlin.crypto.CryptoImpl.Companion.toByteArray
abstract class CryptoImpl : Crypto {
companion object {
fun Int.toByteArray(): ByteArray {
val bytes = ByteArray(4)
bytes[3] = (this and 0xFFFF).toByte()
bytes[2] = ((this ushr 8) and 0xFFFF).toByte()
bytes[1] = ((this ushr 16) and 0xFFFF).toByte()
bytes[0] = ((this ushr 24) and 0xFFFF).toByte()
return bytes
}
fun Long.toByteArray() = ByteArray(8).apply {
var l = this@toByteArray
for (i in 7 downTo 0) {
this[i] = (l and 0xFF).toByte()
l = l shr 8
}
}
}
override fun kdf(outputLength: Int, ikm: ByteArray, salt: ByteArray, info: ByteArray): ByteArray {
return Kdf.kdf(outputLength, ikm, salt, info, { sha256(it) }, { sha512(it) })
}
override fun setupRefreshPlanchet(secretSeed: ByteArray, coinNumber: Int): FreshCoin {
val info = "taler-coin-derivation".encodeToByteArray()
val salt = coinNumber.toByteArray()
val out = kdf(64, secretSeed, salt, info)
val coinPrivateKey = out.copyOfRange(0, 32)
val bks = out.copyOfRange(32, 64)
return FreshCoin(eddsaGetPublic(coinPrivateKey), coinPrivateKey, bks)
}
}
|
