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
|
package net.taler.wallet.kotlin.crypto
abstract class CryptoImpl : Crypto {
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)
}
private 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
}
}
|
