#Cryptography

Recovering the key and text of a 1542 cipher from Cardinal Alessandro Farnese to Giovanni Poggio.

How Devin and a Cognition researcher built the world’s highest-performance GPU lattice siever, to make factoring numbers 10x cheaper than the previous state of the art

Evaluate a degree-n polynomial with about n/2 multiplications. Type a polynomial, pick ℚ, ℝ, ℂ, a Mersenne prime or a binary field, and get the preprocessed evaluation chain as math, C code or a circuit — everything runs in your browser.

Reticulum is the cryptography-based networking stack for building local and wide-area networks with readily available hardware. Reticulum can continue to operate even in adverse conditions with very high latency and extremely low bandwidth.

For (D)TLS 1.2, this document deprecates the use of two key exchanges, namely Diffie-Hellman (DH) over a finite field and RSA. It also discourages the use of static Elliptic Curve Diffie-Hellman (ECDH) cipher suites.…

After a long day of exhausting conversations about Hybrid Post-Quantum Cryptography, random jackasses trying to play gotcha with endpoint attacks against end-to-end encrypted messaging apps, and me…

A Python implementation for all of these algorithms is available in my GitHub repository.

With AI evolving exponentially and solving increasingly difficult problems, how realistic is the threat that quantum computing advances faster than expected? Would Bitcoin realistically be able to adapt in time?…

TLDR; I had some fun playing around with combining columnar transposition with substitution, which turns out to be surprisingly strong. Almost certainly not "properly strong", but not trivial to break with computers either.…

I was in need of replacing my ssh-key for Gitlab today since it expired so I thought I might as well switch over to a PQC protocol rather than Ed25519. I was a bit stunned to find out that this is apparently not supported yet.…

I'm not sure if it's the right subreddit to post in, but I was wondering why AES256 is slower on my CPU (Snapdragon 888 which does have AES acceleration) than ChaCha20 and maybe anybody knows the reason.…

I hope that this is not considered low effort, as I really would like the opinion of this community. I know that you people deal more with the guts of this stuff, but hopefully you'll hear out a layperson.…

Do all modern devices basically reach a point where everyone has to trust the RNG for modern encryption? The software PRNG like dev/urandom can be audited, but how does anyone audit the hardware RNG's?…

Greetings, I'm currently reading W. Friedman's Military Cryptanalysis Part 1 and doing the exercises. I'm getting stuck quite frequently at transpositional crypotgrams, namely the ones where the letters of a word are transposed.…

Is it possible to design a compromised RNG so that it that is both Useful to the attacker, in that they gain significant advantage against messages encrypted using this RNG, and Indistinguishable from an honest RNG for everyone else?…

Example use case, an imageboard where the server hosts a public membership tree containing identity commitments. Each time a user holding an identity secret can generate a new anonymous identity by proving membership within the membership tree and…

Hello! Like the title says. I'm gonna do an internship in Cryptography (it's only one month though! So please don't give me something bigger than I can chew).…

I want to encode a text with a cypher i made up. My idea is to use a caeser cypher to encode every other letter but the remaining letters are encoded with the same number of the cypher in the opposite direction. E.G.…

Hello guys ! I'm organizing a scavenger hunt for my wedding and I want to hide a message in the musical sheet on the piano that I have at the wedding place. The musical sheet are written already but I want to hide a message in it with invisible ink.…