r/crypto

Browser‑only HMAC‑based toy cipher demo (DrMoron) — now live with URL‑encoded ciphertext

I’ve been working on a small educational cipher experiment called DrMoron. Refer to: [https://www.reddit.com/r/crypto/comments/1r369lv/drmoron\_a\_cipher/](https://www.reddit.com/r/crypto/comments/1r369lv/drmoron_a_cipher/) It’s not intended to be secure — just a playground for exploring HMAC‑driven keystream generation, feedback, and deterministic test vectors. I finally finished the browser version, …

The Verification Theater: When Formal Methods Create False Assurance in Cryptographic Libraries

Application-Level Cascading Cipher

[https://positive-intentions.com/blog/cascading-cipher](https://positive-intentions.com/blog/cascading-cipher) i wanted to improve the encryption i was using in my webapp. i already know that webRTC is encrypted by default, but that isnt anywhere near as respected as the signal protocol and it wouldnt be quantum-secure. understandably, people …

DrMoron... A Cipher...

Here is a little cipher I have been working on for some years. I am wondering what you all think about it? Here is an old write up: [http://funwithfractals.atspace.cc/ct\_cipher/](http://funwithfractals.atspace.cc/ct_cipher/) And some code that uses a TRNG, well, it better be …

Landscape of Quantum Computing (with 2025 update)

Why Haven’t Quantum Computers Factored 21 Yet?

Is it correct to state that the Pedersen hash system isn t vulnerable to length extension attack as long as the inputs are a multiple of the number of window s bits?

The original description can be found [here](https://iden3-docs.readthedocs.io/en/latest/iden3_repos/research/publications/zkproof-standards-workshop-2/pedersen-hash/pedersen.html). I m studying the hash for existing systems still using it (the input is then at least 496bits long). My understanding though is if there s no padding, then it s impossible to …

How secure is hardware-based cryptography?

im working with cryptography and there are functions exposed from the hardware to the application. (not relevant, but so you have context) [https://developer.mozilla.org/en-US/docs/Web/API/SubtleCrypto](https://developer.mozilla.org/en-US/docs/Web/API/SubtleCrypto) this is working as expected. under-the-hood it is optimised with the hardware and i can see that …

WhatsApp Clone... But Decentralized and P2P Encrypted Without Install or Signup

By leveraging WebRTC for direct browser-to-browser communication, it eliminates the middleman entirely. Users simply share a unique URL to establish an encrypted, private channel. This approach effectively bypasses corporate data harvesting and provides a lightweight, disposable communication method for those …

In diffie Hellman, is it possible to modify linear combinations so the end result is a multiple of the first result? Does this type of Diffie Hellman problem has a specific name?

Let s say I ve `D=i×A+n×B+k×C` like `D=55×A+36×B+578×C` over an elliptic curve with a large prime number and the discrete logarithm between each point being unknown. If `i` is a whitelisted constant, is it possible to modify `n` and `k` …