Added secretbox functions and constants

multiplatform-crypto-libsodium-bindings/src/commonMain/kotlin/com.ionspin.kotlin.crypto/secretbox/SecretBox.kt

@@ -0,0 +1,30 @@
+package com.ionspin.kotlin.crypto.secretbox
+
+import kotlin.js.JsName
+
+/**
+ * Created by Ugljesa Jovanovic
+ * ugljesa.jovanovic@ionspin.com
+ * on 29-Aug-2020
+ */
+
+val crypto_secretbox_KEYBYTES = 32
+val crypto_secretbox_MACBYTES = 16
+val crypto_secretbox_NONCEBYTES = 24
+
+class SecretBoxCorruptedOrTamperedDataExceptionOrInvalidKey() : RuntimeException("MAC validation failed. Data is corrupted or tampered with.")
+
+data class SecretBoxEncryptedDataAndTag(
+    @JsName("data")
+    val data: UByteArray, val tag: UByteArray)
+
+expect object SecretBox {
+
+    fun easy(message : UByteArray, nonce: UByteArray, key: UByteArray) : UByteArray
+    fun openEasy(ciphertext: UByteArray, nonce: UByteArray, key: UByteArray) : UByteArray
+
+    fun detached(message: UByteArray, nonce: UByteArray, key: UByteArray) : SecretBoxEncryptedDataAndTag
+    fun openDetached(ciphertext: UByteArray, tag: UByteArray, nonce: UByteArray, key: UByteArray) : UByteArray
+
+    fun keygen() : UByteArray
+}

multiplatform-crypto-libsodium-bindings/src/commonMain/kotlin/com.ionspin.kotlin.crypto/secretstream/SecretStream.kt

@@ -4,6 +4,8 @@ package com.ionspin.kotlin.crypto.secretstream
  * Created by Ugljesa Jovanovic
  * ugljesa.jovanovic@ionspin.com
  * on 26-Aug-2020
+ *
+ * This file is named with Jvm suffix because of https://youtrack.jetbrains.com/issue/KT-21186
  */
 expect class SecretStreamState
 
@@ -20,6 +22,8 @@ val crypto_secretstream_xchacha20poly1305_HEADERBYTES = 24
 val crypto_secretstream_xchacha20poly1305_KEYBYTES = 32
 val crypto_secretstream_xchacha20poly1305_ABYTES = 17
 
+class SecretStreamCorrupedOrTamperedDataException() : RuntimeException("MAC validation failed. Data is corrupted or tampered with.")
+
 expect object SecretStream {
 
     fun xChaCha20Poly1305InitPush(key: UByteArray) : SecretStreamStateAndHeader