Add parameter validation for AES-CTR
diff --git a/include/mbedtls/aes.h b/include/mbedtls/aes.h
index 93522e6..ae80e9d 100644
--- a/include/mbedtls/aes.h
+++ b/include/mbedtls/aes.h
@@ -561,15 +561,21 @@
* securely discarded as soon as it's no longer needed.
*
* \param ctx The AES context to use for encryption or decryption.
+ * It must be initialized and bound to a key.
* \param length The length of the input data.
* \param nc_off The offset in the current \p stream_block, for
* resuming within the current cipher stream. The
* offset pointer should be 0 at the start of a stream.
+ * It must point to a valid \c size_t.
* \param nonce_counter The 128-bit nonce and counter.
+ * It must be a readable-writeable buffer of 16 Bytes.
* \param stream_block The saved stream block for resuming. This is
* overwritten by the function.
+ * It must be a readable-writeable buffer of 16 Bytes.
* \param input The buffer holding the input data.
+ * It must be readable and of size \p length.
* \param output The buffer holding the output data.
+ * It must be writeable and of size \p length.
*
* \return \c 0 on success.
*/