# Crypto1

Crypto1 is a proprietary stream cipher and authentication protocol created by NXP for its MIFARE Classic RFID contactless smart cards  launched in 1994. However, it was reverse engineered by cryptographic researchers in 2008 [1]. Soon after, a variety of attacks were published that effectively broke the security [2], even for patched and hardened MIFARE Classic cards [3] [4]. 

This could be an example for us to learn how stream cipher and authentication protocols work, and how to implement practical attacks against them.

## Reference

[1] Garcia, Flavio D., et al. "Dismantling MIFARE classic." *European symposium on research in computer security*. Springer, Berlin, Heidelberg, 2008.

[2] Koning Gans, Gerhard de, Jaap-Henk Hoepman, and Flavio D. Garcia. "A practical attack on the MIFARE Classic." *International Conference on Smart Card Research and Advanced Applications*. Springer, Berlin, Heidelberg, 2008.

[3] Chiu, Yi-Hao, et al. "A practical attack on patched MIFARE Classic." *International Conference on Information Security and Cryptology*. Springer, Cham, 2013.

[4] Meijer, Carlo, and Roel Verdult. "Ciphertext-only cryptanalysis on hardened Mifare classic cards." *Proceedings of the 22nd ACM SIGSAC Conference on Computer and Communications Security*. 2015.

