A command-line tool to encrypt and decrypt files using AES.

AES algorithms are implemented as a standalone C99 library (aes.* files).

Supported features:

key sizes: 128, 192, 256-bits
mode: ECB, CBC

Installation

1. Compile aes library and commande line interface for encryption/decryption

make

2. Compile and run tests

After compiling the tool, you can compile and run tests with:

make test

These tests are performed for cipher and decipher, and for all size key (Using NIST’s documentation examples).

3. Benchmarks

make bench

Give the encryption runtime (in seconds) and max memory footprints (in bytes) after N=100 iterations for all modes and all sizes key. You can also give an other value to N, for example with 50:

make bench N=50

Usage and help

To see help in shell use: ./AES -h

Usage:
./AES [-d] [-m MODE] [-k FILE|STR] [-s SIZE] [-v] [-h] FILE
Arguments:
   -d,   Enable decrypt mode (default is encrypt)
   -m,   Expects string MODE (default is ECB)
                        MODE = ECB | CBC
   -k,   Can be a hex string or path to file that contains hex string
                       - For example to set a 128-bits use
                        -k 0102030405060708090A0B0C0D0E0F10
                        or put the same string in a file and give file path to -k
   -s,   Create a random key in a file named rkey.key
   -v,   Enable verbose mode
   -h,   Show this message and exit

Examples

Encrypt the text named alice with the file key256 which countain a 256-bits key with default mode (EBC):
```
./AES -k toys/key256 toys/alice
```
This command create a new file named cipher which contain the encrypted text.
Decryption of previous cipher text:
```
./AES -k toys/key256 -d cipher
```
This command create a new file named decipher which contain the decrypted text.
Using CBC mode with a random 192-bits key:
- Encryption: ./AES -s 192 -m CBC toys/alice (Create both an I.V. in iv and a random key in rkey.key).
- Decryption: ./AES -k rkey.key -m CBC -d cipher (Use the previously created iv)