How to Perform Security Analysis and Generate Reports for Python AEAD Cipher?

[harikartik]

Hi all,
I’ve implemented a custom Authenticated Encryption with Associated Data (AEAD) algorithm in Python. The core functionalities are working — encryption, decryption, key/nonce handling, and tag generation are all in place.

Now, I want to take the next step and:

1. Test the correctness of my implementation.
2. Benchmark its performance (e.g., throughput, memory).
3. Generate security analysis reports, such as:

• differential or linear cryptanalysis testing,
• permutation property checks (e.g., avalanche, bias),
• resistance against forgery/adversarial queries,
• compliance with CAESAR/NIST-style test vectors (if applicable),
• or anything relevant to AEAD schemes.

Thanks!

[peacker]

Hi @harikartik! Thanks for posting your question here.

First, let me clarify that CLAASP can only perform automated cryptanalysis on:

• cryptographic permutations
• block ciphers
• update functions of a stream cipher
• compression functions of hash functions
  It is not designed to analyze the mode of operation of the above functions.
  That said, among the things you listed, CLAASP can surely help. You only need to implement your function (the permutation in your case, not the full AEAD construction) in CLAASP (in this comment Testing AES with dynamic S-Boxes #336 (comment), you can see an example on how to build a cipher. You can also see another example from page 10 of this pdf: https://skcamworkshop.github.io/skcam2025/assets/docs/slides/Bellini_slides.pdf)

To reply more in detail to your question, let me go point by point:

1. Test the correctness of my implementation.
   -> YES, the first thing you need to do is implement your function (see above references)

2. Benchmark its performance (e.g., throughput, memory).
   -> NOT really. You can generate python or C code with CLAASP, but they are not optimal for performance.

3. Generate security analysis reports, such as:
   -> YES! this is the main purpose of CLAASP, let's see each of your sub-points

• differential or linear cryptanalysis testing,
  -> YES
• permutation property checks (e.g., avalanche, bias),
  -> YES
• resistance against forgery/adversarial queries,
  -> NO, this is at the mode of operation level
• compliance with CAESAR/NIST-style test vectors (if applicable),
  -> not sure what you mean here. All existing ciphers in CLAASP are usually tested agains official test vectors. If you have your own permutation, there is no compliance to be tested.
• or anything relevant to AEAD schemes.
  -> you can perform many other tests with CLAASP, for example:
  • search for impossible differentials
  • search for differential-linear distinguishers
  • search for neural distinguishers
  • ...
    see this paper for a good overview of what is possible to do with CLAASP and how to do it (the paper has scripts): https://eprint.iacr.org/2024/1324.pdf

Hope this helps, and if you have further questions do not hesitate to reply to this message!

[harikartik]

Thanks a lot for the detailed clarification - this really helps!