added expernal nonce support,

fixed key-based crypt functions
added hashes support

src/commonTest/kotlin/KeysTest.kt

@@ -85,6 +85,25 @@ class KeysTest {
         }
     }
 
+    @Test
+    fun symmetricKeyTest() = runTest {
+        initCrypto()
+        val k1 = SymmetricKey.random()
+        val src = "Buena Vista".encodeToUByteArray()
+        val nonce = k1.randomNonce()
+
+        assertContentEquals(src, k1.decryptWithNonce(k1.encryptWithNonce(src, nonce), nonce))
+        assertThrows<DecryptionFailedException> {
+            val n2 = nonce.copyOf()
+            n2[4] =  n2[4].inv()
+            k1.decryptWithNonce(k1.encryptWithNonce(src, nonce), n2)
+        }
+
+        assertContentEquals(src, k1.decrypt(k1.encrypt(src)))
+        assertContentEquals(src, k1.decrypt(k1.encrypt(src, 0..117)))
+        assertContentEquals(src, k1.decrypt(k1.encrypt(src, 7..117)))
+    }
+
     @Test
     fun keyExchangeTest() = runTest {
         initCrypto()
@@ -105,6 +124,8 @@ class KeysTest {
         assertEquals(src, clientSessionKey.decryptString(serverSessionKey.encrypt(src)))
         assertEquals(src, clientSessionKey.decryptString(serverSessionKey.encrypt(src)))
 
+        assertContentEquals(clientSessionKey.sessionTag, serverSessionKey.sessionTag)
+
     }
 
     @Test