Improved Meet-in-the-Middle Attacks on Round-Reduced Crypton-256

The meet-in-the-middle (MITM) attack has prove to be efficient in analyzing the AES block cipher. Its efficiency has been increasing with the introduction of various techniques such as differential enumeration, key-dependent sieve, super-box etc. The recent MITM attack given by Li and Jin has successfully mounted to 10-round AES-256. Crypton is an AES-like block cipher. In this paper, we apply the MITM method to the cryptanalysis of Crypton-256. Following Li and Jin\u27s idea, we give the first 6-round distinguisher for Crypton. Based on the distinguisher as well as the properties of Crypton\u27s simple key schedule, we successfully launch MITM attacks on Crypton-256 reduced to 9 and 10 rounds. For 9-round Crypton-256, our MITM attack can recover the 256-bit key with a time complexity $2^{173.05}$, a memory complexity $2^{241.17}$. For the 10-round version, we give two MITM attacks. The basic attack requires a time complexity $2^{240.01}$ and memory complexity $2^{241.59}$. The time/memory complexity of the advanced MITM attack on 10-round Crypton is $2^{245.05}/2^{209.59}$. Our MITM attacks share the same data complexity $2^{113}$ and their error rates are negligible

Implementation of AES-256 Algorithm in Android-Based E-Voting Data Security

E-voting is a method of voting and vote counting in general elections using digital devices. There are still many errors and fraud that occur during village head elections in Indonesia. Then the idea was created to carry out village head elections by utilizing existing technological developments, especially Android-based smartphone technology. The data source used in this study is secondary data which uses population data of citizens who will exercise their right to vote, vote data for citizens' voting rights, and data from the results of vote acquisition during the village head election process. In this study, a number of important data were needed in the village head election process which was carried out using documentation techniques. This research produced an Android-based application system for securing e-voting data for village head elections using the AES-256 cryptographic algorithm called Vodes. The application produced in this study was built using the Kotlin programming language on the Android frontend side by utilizing the Android Studio IDE as a tool in the development process. While on the backend side it uses the Javascript programming language using the Node js framework. The database used in the Vodes application uses MySQL. Based on the results of this study, it can be concluded that an e-voting data security application for village head elections has been created using the AES-256 cryptographic algorithm. The application produced in this study has succeeded in properly securing all aspects of the data in the village head election processE-voting adalah metode pemungutan dan penghitungan suara dalam pemilihan umum dengan menggunakan perangkat digital. Masih banyak kesalahan dan kecurangan yang terjadi pada pemilihan kepala desa di Indonesia. Maka terciptalah ide untuk melaksanakan pemilihan kepala desa dengan memanfaatkan perkembangan teknologi yang ada khususnya teknologi smartphone berbasis android. Sumber data yang digunakan dalam penelitian ini adalah data sekunder yang menggunakan data kependudukan warga yang akan menggunakan hak pilihnya, data suara untuk hak pilih warga, dan data hasil perolehan suara selama proses pemilihan kepala desa. Dalam penelitian ini dibutuhkan beberapa data penting dalam proses pemilihan kepala desa yang dilakukan dengan menggunakan teknik dokumentasi. Penelitian ini menghasilkan sistem aplikasi berbasis Android untuk pengamanan data e-voting pemilihan kepala desa dengan menggunakan algoritma kriptografi AES-256 yang disebut Vodes. Aplikasi yang dihasilkan pada penelitian ini dibangun menggunakan bahasa pemrograman Kotlin pada sisi frontend Android dengan memanfaatkan IDE Android Studio sebagai alat bantu dalam proses pengembangan. Sedangkan pada sisi backend menggunakan bahasa pemrograman Javascript dengan menggunakan framework Node js. Database yang digunakan pada aplikasi Vodes menggunakan MySQL. Berdasarkan hasil penelitian dapat disimpulkan bahwa telah dibuat sebuah aplikasi keamanan data e-voting pemilihan kepala desa dengan menggunakan algoritma kriptografi AES-256. Aplikasi yang dihasilkan dalam penelitian ini telah berhasi