Implemeting _stream_ primitives, at elast the ones available in lazy sodium

multiplatform-crypto-libsodium-bindings/src/nativeMain/kotlin/com/ionspin/kotlin/crypto/stream/Stream.kt

@@ -0,0 +1,152 @@
+package com.ionspin.kotlin.crypto.stream
+
+import com.ionspin.kotlin.crypto.util.toPtr
+import kotlinx.cinterop.convert
+import kotlinx.cinterop.pin
+import libsodium.crypto_stream_KEYBYTES
+import libsodium.crypto_stream_chacha20
+import libsodium.crypto_stream_chacha20_ietf_xor
+import libsodium.crypto_stream_chacha20_ietf_xor_ic
+import libsodium.crypto_stream_chacha20_keygen
+import libsodium.crypto_stream_chacha20_xor
+import libsodium.crypto_stream_chacha20_xor_ic
+
+actual object Stream {
+    actual fun chacha20(clen: Int, nonce: UByteArray, key: UByteArray): UByteArray {
+        val result = UByteArray(clen)
+        val resultPinned = result.pin()
+        val noncePinned = nonce.pin()
+        val keyPinned = key.pin()
+
+        crypto_stream_chacha20(resultPinned.toPtr(), clen.convert(), noncePinned.toPtr(), keyPinned.toPtr())
+
+        resultPinned.unpin()
+        noncePinned.unpin()
+        keyPinned.unpin()
+
+        return result
+    }
+
+    actual fun chacha20IetfXor(
+        message: UByteArray,
+        nonce: UByteArray,
+        key: UByteArray
+    ): UByteArray {
+        val result = UByteArray(message.size)
+        val messagePinned = message.pin()
+        val resultPinned = result.pin()
+        val noncePinned = nonce.pin()
+        val keyPinned = key.pin()
+
+        crypto_stream_chacha20_ietf_xor(
+            resultPinned.toPtr(),
+            messagePinned.toPtr(),
+            message.size.convert(),
+            noncePinned.toPtr(),
+            keyPinned.toPtr()
+        )
+
+        messagePinned.unpin()
+        resultPinned.unpin()
+        noncePinned.unpin()
+        keyPinned.unpin()
+
+        return result
+    }
+
+    actual fun chacha20IetfXorIc(
+        message: UByteArray,
+        nonce: UByteArray,
+        initialCounter: ULong,
+        key: UByteArray
+    ): UByteArray {
+        val result = UByteArray(message.size)
+        val messagePinned = message.pin()
+        val resultPinned = result.pin()
+        val noncePinned = nonce.pin()
+        val keyPinned = key.pin()
+
+        crypto_stream_chacha20_ietf_xor_ic(
+            resultPinned.toPtr(),
+            messagePinned.toPtr(),
+            message.size.convert(),
+            noncePinned.toPtr(),
+            initialCounter.convert(),
+            keyPinned.toPtr()
+        )
+
+        messagePinned.unpin()
+        resultPinned.unpin()
+        noncePinned.unpin()
+        keyPinned.unpin()
+
+        return result
+    }
+
+    actual fun chacha20Keygen(): UByteArray {
+        val result = UByteArray(crypto_stream_chacha20_KEYBYTES)
+        val resultPinned = result.pin()
+
+        crypto_stream_chacha20_keygen(resultPinned.toPtr())
+
+        resultPinned.unpin()
+
+        return result
+    }
+
+    actual fun chacha20Xor(
+        message: UByteArray,
+        nonce: UByteArray,
+        key: UByteArray
+    ): UByteArray {
+        val result = UByteArray(message.size)
+        val messagePinned = message.pin()
+        val resultPinned = result.pin()
+        val noncePinned = nonce.pin()
+        val keyPinned = key.pin()
+
+        crypto_stream_chacha20_xor(
+            resultPinned.toPtr(),
+            messagePinned.toPtr(),
+            message.size.convert(),
+            noncePinned.toPtr(),
+            keyPinned.toPtr()
+        )
+
+        messagePinned.unpin()
+        resultPinned.unpin()
+        noncePinned.unpin()
+        keyPinned.unpin()
+
+        return result
+    }
+
+    actual fun chacha20XorIc(
+        message: UByteArray,
+        nonce: UByteArray,
+        initialCounter: ULong,
+        key: UByteArray
+    ): UByteArray {
+        val result = UByteArray(message.size)
+        val messagePinned = message.pin()
+        val resultPinned = result.pin()
+        val noncePinned = nonce.pin()
+        val keyPinned = key.pin()
+
+        crypto_stream_chacha20_xor_ic(
+            resultPinned.toPtr(),
+            messagePinned.toPtr(),
+            message.size.convert(),
+            noncePinned.toPtr(),
+            initialCounter.convert(),
+            keyPinned.toPtr()
+        )
+
+        messagePinned.unpin()
+        resultPinned.unpin()
+        noncePinned.unpin()
+        keyPinned.unpin()
+
+        return result
+    }
+}