Complete · Technology · Security

Cryptopals

Working through the Cryptopals crypto challenges in PHP, one per post: encodings, XOR, frequency analysis and breaking real ciphers, with value objects and tests along the way.

9 parts

Start at part 1

01 The Cryptopals challenges Starting today I kick off a series on the cryptopals crypto challenges, with my implementations in PHP. Feel free to join in the fun! Feb 14, 2022
02 Cryptopals: Set 1 – challenge 1 Challenge 1 in the cryptopals suite is to juggle between Base64 and Hex encoding of byte strings. Let's do just that, with value objects! Feb 15, 2022
03 Cryptopals: Set 1 – challenge 2 Building on our cryptopals encoding work last time, let's introduce byte-based XOR operations. Feb 16, 2022
04 Cryptopals: Set 1 – challenge 3 Next up in our Cryptopals walkthrough is some frequency analysis against simple cryptographic keys. Let's have some fun! Feb 17, 2022
05 Cryptopals: Set 1 – challenge 4 Now that we know how to crack a single-byte XOR cipher, let's expand and crack even more through Cryptopals' next challenge. Feb 18, 2022
06 Cryptopals: Set 1 – challenge 5 Breaking encryption is fun. Building an encryption cipher is even more so! Let's continue our Cryptopals journey with XOR. Feb 19, 2022
07 Cryptopals: Set 1 – challenge 6 A return to Cryptopals means we get to break the repeating-key cipher we were working with before. Breaking crypto is fun! Mar 12, 2022
08 Cryptopals: Set 1 – challenge 7 Next up with Cryptopals is a challenge to decrypt AES in ECB mode. This is relatively easy in PHP! Mar 13, 2022
09 Cryptopals: Set 1 – challenge 8 The final Cryptopals challenge in set 1 involves detecting AES when used in ECB mode. It will become a handy utility later on … Mar 14, 2022

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