http://ocw.cs.pub.ro/courses/ 2026-04-08T18:31:40+03:00 http://ocw.cs.pub.ro/courses/ http://ocw.cs.pub.ro/courses/lib/tpl/arctic/images/favicon.ico text/html 2024-12-13T10:54:05+03:00 http://ocw.cs.pub.ro/courses/ac/laboratoare/01?rev=1734080045&do=diff Lab 01 - Introduction This laboratory will serve as an introduction to Python and the Caesar cipher. To solve the lab, open this Colab notebook and copy it into your own drive for persistence. Do so by going to File -> Save a copy in Drive. C1 = "000100010001000000001100000000110001011100000111000010100000100100011101000001010001100100000101" C2 = "02030F07100A061C060B1909" key = "abcdefghijkl" # Solve here P1 = bin_2_str(bitxor(str_2_bin(key), C1)) print(P1) P2 = bin_2_str(bitxor(str_2_bi… text/html 2024-10-11T20:41:35+03:00 http://ocw.cs.pub.ro/courses/ac/laboratoare/02?rev=1728668495&do=diff Lab 02 - Vigenère and DES This laboratory will cover frequency attacks against the Vigenère cipher and the meet-in-the-middle attack on 2DES. To solve the lab, open this Colab notebook and copy it into your own drive for persistence. text/html 2024-11-07T01:56:16+03:00 http://ocw.cs.pub.ro/courses/ac/laboratoare/03?rev=1730937376&do=diff Lab 03 - CBC Padding Oracle Attack This laboratory will cover Sergey Vaudenay's attack on CBC padding. To solve the lab, open this Colab notebook and copy it into your own drive for persistence. text/html 2022-10-27T15:58:42+03:00 http://ocw.cs.pub.ro/courses/ac/laboratoare/04?rev=1666875522&do=diff Lab 04 - Public Key Encryption Before starting the labs, download openssl 1.1.1 from here. Save the file to some local folder accessible by you, then compile it and install it to some folder. Open the unpacked folder from bash, and run the following commands: text/html 2022-11-03T17:05:39+03:00 http://ocw.cs.pub.ro/courses/ac/laboratoare/05?rev=1667487939&do=diff Lab 05 - PKI and TLS here Public Key Infrastructure In cryptography, a PKI is an arrangement that binds public keys with respective identities of entities (like people and organizations). The binding is established through a process of registration and issuance of certificates at and by a certificate authority (CA). text/html 2024-11-07T01:57:31+03:00 http://ocw.cs.pub.ro/courses/ac/laboratoare/06?rev=1730937451&do=diff Lab 06 - TLS Attacks - BEAST This laboratory will cover the BEAST attack against the TLS 1.0 implementation of AES-CBC. To solve the lab, open this Colab notebook and copy it into your own drive for persistence. text/html 2025-07-30T20:46:37+03:00 http://ocw.cs.pub.ro/courses/ac/laboratoare/07?rev=1753897597&do=diff Lab 07 - Whatsapp End-to-end Encryption In this lab you will implement a simplified version of the Signal Protocol, which is the basis for WhatsApp's end-to-end encryption. The first versions of the Whatsapp protocol were described here. A more recent document is available here. WhatsApp's security is based on the Signal protocol, which was first used by TextSecure. The Signal protocol is described in detail in this paper. text/html 2024-11-14T13:05:23+03:00 http://ocw.cs.pub.ro/courses/ac/laboratoare/08?rev=1731582323&do=diff Lab 08 - Whatsapp End-to-end Encryption (part 2) In this lab you will continue the implementation of the Signal Protocol, which is the basis for WhatsApp's end-to-end encryption. The protocol is described here. For more details you can also check this paper. text/html 2025-11-20T11:37:53+03:00 http://ocw.cs.pub.ro/courses/ac/laboratoare/09?rev=1763631473&do=diff Lab 09 - EMV Basics We have presented in class the basic communication mechanisms in EMV, the protocol used in banking transactions. We have seen the low-level communication layer, as well as the higher layers of communication, including the format of commands (CAPDUs) and responses (RAPDUs). Furthermore, we have also seen an example of transaction. text/html 2025-11-20T11:39:16+03:00 http://ocw.cs.pub.ro/courses/ac/laboratoare/10?rev=1763631556&do=diff Lab 10: EMV crypto - Verifying a DDA Signature Install python tools to work with your smartcard Do the following on Linux (this is for Ubuntu/Debian -- you might need root access): * Install these packages: sudo apt install libpcsclite-dev swig libpcsc-perl pcsc-tools python3-dev libudev-dev python3-pyscard python3-pyserial text/html 2025-11-06T10:36:08+03:00 http://ocw.cs.pub.ro/courses/ac/laboratoare/11?rev=1762418168&do=diff Lab 6b - TOFU-based Authenticated Key Exchange In this lab, we will implement Trust On First Use in a manner similar to that of SSH. We will base our implementation around PyCryptodome - you can find the relevant documentation here. 0. Init Use these commands to generate a private key and a Diffie-Hellman parameter file: text/html 2025-01-15T01:16:28+03:00 http://ocw.cs.pub.ro/courses/ac/laboratoare/12?rev=1736896588&do=diff Lab 12 - Post-Quantum Cryptography In this laboratory, we will look at implementing a basic form of key exchange within post-quantum cryptography. We will be using liboqs. To install it on Ubuntu, use the command below: sudo apt install astyle cmake gcc ninja-build libssl-dev python3-pytest python3-pytest-xdist unzip xsltproc doxygen graphviz python3-yaml valgrind