Posts
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` such as the new D is a multiple of the …
Review request: combining age (scrypt passphrase) with Shamir secret sharing for offline, browser-based recovery
Hi r/crypto, I’m looking for technical critique of a small tool I built that combines **age** encryption with **Shamir’s Secret Sharing** and a **self-contained browser recovery tool**. Repo: [https://github.com/eljojo/rememory](https://github.com/eljojo/rememory) Docs: [https://eljojo.github.io/rememory/docs.html](https://eljojo.github.io/rememory/docs.html) # Problem I’m trying to solve How can non-technical people recover encrypted secrets if the owner is suddenly unavailable, …
Collision Resistance of HMACs
Hi everyone. I am studying HMACs and I just wanted to double-check: the collision resistance of an HMAC checksum is roughly half of the bit size of the checksum itself, right? So for example HMAC-SHA-256 has a collision resistance of 128 bits due to the birthday paradox. Please let me …
Is there a way to modify this elliptic curve diffie Hellman equation like this?
Let s denote `e()` a bilinear elliptic curve pairing. Let s say I have `e(-A,B)==e(C,D)` or `e(A,B)*e(C,D)==1` where *C* and *A* are in G1 and *B* and *D* in G2. Without knowing the discrete logarithms between the points, I can alter the equation by doing something like `e(A,B+n×D)*e(C+n×A,D)==1` where `n` …
Chat Control is being pushed again
What s the shortest possible number of Miller loops for bn254 and bls12-381 elliptic curves for getting a bilinear pairing?
There s many paper that explore making bilinear pairings efficient, but as far I understand, they also aim at making the final exponentiation simpler. In my case I [have an inversion algorithm whose complexity is if I understand correctly O(k(2^(s^²)))^(3.3k))](https://drive.google.com/file/d/1SXS1h-6Tywdj9_1XlMRhrS0piHl7DrLG/view). Where *k* is the embdedding degree and *s* is the …
Are there any good tutorials on post-quantum cryptography?
as the title says. id like to learn more. there are a few videos out there, but i havent come across something like an article or practical tutorial that explains it. perhaps there is a book or something you'd suggest to learn about it? (ive used AI, and it seems …
I built a ZK proof visualizer while learning - perhaps it is useful to you
I was learning ZK proofs and found that visualizing things really helped me understand them. I noticed there aren't many interactive visualizations out there, so I contributed to the area myself. Here's the first version: zkvisualizer.com It walks through the full pipeline step by step (Problem → Circuit → R1CS …
Building cryptographic agility into Sigstore
Transaction-Governed Security/Execution-Time Security: cryptographic enforcement of irreversible actions at authorization time
I am exploring a security model I refer to as **Transaction-Governed Security (TGS)** Or **Execution-Time Security** and would appreciate discussion focused on *cryptographic framing, threat models, and prior art*. This is **not** about currency systems, blockchains, or economic mechanisms. The term “transaction” here means *any irreversible action* (e.g. state mutation, …