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# Qt-AES
Small and portable AES encryption class for Qt.
Supports all key sizes - 128/192/256 bits - ECB, CBC and CFB modes
## Usage
### Available Methods
```
//Encode of rawText with key
//iv is used in CBC mode
//return the encrypted byte array
QByteArray encode(const QByteArray rawText, const QByteArray key, const QByteArray iv = NULL);
//Decode of rawText with key
//iv is used in CBC mode
//return the decrypted byte array
QByteArray decode(const QByteArray rawText, const QByteArray key, const QByteArray iv = NULL);
//Key expansion in Rijndael schedule
//return the new expanded key as byte array
QByteArray expandKey(const QByteArray key);
```
The same methods are available as static calls
```
QAESEncryption::Crypt => encode(...)
QAESEncryption::Decrypt => decode(...)
QAESEncryption::ExpandKey => expandKey(...)
```
#### Padding
By default the padding method is `ISO`, however, the class supports:
```
ZERO
PKCS7
ISO
```
### Example
Sample code using a 128bit key in ECB mode
```
#include "qaesencryption.h"
QAESEncryption encryption(QAESEncryption::AES_128, QAESEncryption::ECB);
QByteArray encodedText = encryption.encode(plainText, key);
QByteArray decodedText = encryption.decode(encodedText, key);
```
Example for 256bit CBC using QString
```
#include <QCryptographicHash>
#include "qaesencryption.h"
QAESEncryption encryption(QAESEncryption::AES_256, QAESEncryption::CBC);
QString inputStr("The Advanced Encryption Standard (AES), also known by its original name Rijndael "
"is a specification for the encryption of electronic data established by the U.S. "
"National Institute of Standards and Technology (NIST) in 2001");
QString key("your-string-key");
QString iv("your-IV-vector");
QByteArray hashKey = QCryptographicHash::hash(key.toLocal8Bit(), QCryptographicHash::Sha256);
QByteArray hashIV = QCryptographicHash::hash(iv.toLocal8Bit(), QCryptographicHash::Md5);
QByteArray encodeText = encryption.encode(inputStr.toLocal8Bit(), hashKey, hashIV);
QByteArray decodeText = encryption.decode(encodeText, hashKey, hashIV);
QString decodedString = QString(encryption.removePadding(decodeText));
//decodedString == inputStr !!
```
### Example via static invocation
Static invocation without creating instances, 256 bit key, ECB mode, starting from *QString* text/key
```
#include <QCryptographicHash>
#include "qaesencryption.h"
QString inputStr("The Advanced Encryption Standard (AES), also known by its original name Rijndael "
"is a specification for the encryption of electronic data established by the U.S. "
"National Institute of Standards and Technology (NIST) in 2001");
QString key("your-string-key");
QString iv("your-IV-vector");
QByteArray hashKey = QCryptographicHash::hash(key.toLocal8Bit(), QCryptographicHash::Sha256);
QByteArray hashIV = QCryptographicHash::hash(iv.toLocal8Bit(), QCryptographicHash::Md5);
//Static invocation
QByteArray encrypted = QAESEncryption::Crypt(QAESEncryption::AES_256, QAESEncryption::CBC,
inputStr.toLocal8Bit(), hashKey, hashIV);
//...
// Removal of Padding via Static function
QString decodedString = QString(QAESEncryption::RemovePadding(decodeText));
```
## Unit Testing
The unit testing vectors used are included in [NIST-Recommendation for Block Cipher Modes of Operation](http://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38a.pdf)
Please note that this code is not audited or AES-certified by any competent authority, use it at your own risk.
## Dependencies
* qtcore
No OpenSSL required.
## Contact
Question or suggestions are welcome!
Please use the GitHub issue tracking to report suggestions or issues.
## License
This software is provided under the [UNLICENSE](http://unlicense.org/)