circuitpython/shared-bindings/aesio/__init__.c
Sean Cross b168784fa0 aesio: add basic AES encryption and decryption
This adds initial support for an AES module named aesio.  This
implementation supports only a subset of AES modes, namely
ECB, CBC, and CTR modes.

Example usage:

```
>>> import aesio
>>>
>>> key = b'Sixteen byte key'
>>> cipher = aesio.AES(key, aesio.MODE_ECB)
>>> output = bytearray(16)
>>> cipher.encrypt_into(b'Circuit Python!!', output)
>>> output
bytearray(b'E\x14\x85\x18\x9a\x9c\r\x95>\xa7kV\xa2`\x8b\n')
>>>
```

This key is 16-bytes, so it uses AES128.  If your key is 24- or 32-
bytes long, it will switch to AES192 or AES256 respectively.

This has been tested with many of the official NIST test vectors,
such as those used in `pycryptodome` at
39626a5b01/lib/Crypto/SelfTest/Cipher/test_vectors/AES

CTR has not been tested as NIST does not provide test vectors for it.

Signed-off-by: Sean Cross <sean@xobs.io>
2020-05-06 17:40:06 +08:00

80 lines
2.6 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2017 Scott Shawcroft for Adafruit Industries
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdint.h>
#include "py/obj.h"
#include "py/runtime.h"
#include "__init__.h"
//| :mod:`aesio` --- AES encryption routines
//| ========================================
//|
//| .. module:: aesio
//| :synopsis: Embedded implementation of AES
//|
//| The `AES` module contains classes used to implement encryption
//| and decryption. It aims to be low overhead in terms of memory.
//|
//|
//| Libraries
//|
//| .. toctree::
//| :maxdepth: 3
//|
//| aes
STATIC const mp_obj_tuple_t mp_aes_key_size_obj = {
{&mp_type_tuple},
3,
{
MP_OBJ_NEW_SMALL_INT(16),
MP_OBJ_NEW_SMALL_INT(24),
MP_OBJ_NEW_SMALL_INT(32),
}
};
STATIC const mp_rom_map_elem_t aesio_module_globals_table[] = {
{MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_aesio)},
{MP_ROM_QSTR(MP_QSTR_AES), MP_ROM_PTR(&aesio_aes_type) },
{MP_ROM_QSTR(MP_QSTR_MODE_ECB), MP_ROM_INT(AES_MODE_ECB)},
{MP_ROM_QSTR(MP_QSTR_MODE_CBC), MP_ROM_INT(AES_MODE_CBC)},
{MP_ROM_QSTR(MP_QSTR_MODE_CTR), MP_ROM_INT(AES_MODE_CTR)},
{MP_ROM_QSTR(MP_QSTR_block_size), MP_ROM_INT(AES_BLOCKLEN)},
{MP_ROM_QSTR(MP_QSTR_key_size), (mp_obj_t)&mp_aes_key_size_obj},
};
STATIC MP_DEFINE_CONST_DICT(aesio_module_globals, aesio_module_globals_table);
const mp_obj_module_t aesio_module = {
.base = {&mp_type_module},
.globals = (mp_obj_dict_t *)&aesio_module_globals,
};