Hacker News: tgies

Show HN: Copy-fail-C – portable C port of CVE-2026-31431, with a checker

tgies — Thu, 30 Apr 2026 17:12:42 +0000

This is a C port of Theori/Xint's Copy Fail PoC (https://copy.fail/, 2026-04-29). The original depended on Python and embedded x86_64 shellcode. I managed to reimplement the shellcode as portable C using nolibc borrowed from the kernel, and now the whole thing can be compiled for & works on any arch supported by nolibc.

Comments URL: https://news.ycombinator.com/item?id=47965485

Points: 4

# Comments: 0

New comment by tgies in "Copy Fail"

tgies — Thu, 30 Apr 2026 01:00:42 +0000

fixed: https://github.com/tgies/copy-fail-c

New comment by tgies in "Copy Fail"

tgies — Thu, 30 Apr 2026 00:59:35 +0000

I have a C translation here that should be pretty readable https://github.com/tgies/copy-fail-c

New comment by tgies in "Copy Fail"

tgies — Thu, 30 Apr 2026 00:41:32 +0000

The Python dependency is easily eliminated, and the x86_64 payload made cross-platform: https://github.com/tgies/copy-fail-c

Show HN: MegaHAL in Pure SQL

tgies — Thu, 19 Feb 2026 15:26:01 +0000

I ported Jason Hutchens' 1998 Loebner Prize-winning chatbot, MegaHAL, to run entirely inside PostgreSQL, in pure SQL. The entire lifecycle -- tokenization, learning, keyword extraction, Markov chain generation, and entropy scoring -- is implemented in standard SQL using complex CTEs. There is no PL/pgSQL or any other sort of procedural escape hatch.

Learning is a single ~560-line SQL statement that splits text, interns symbols, and updates two 5th-order Markov tries (forward and backward) using depth-unrolled writable CTEs. Inference is a recursive query that generates N candidate replies in parallel. It performs bidirectional weighted random walks, evaluates them for information-theoretic surprise, and formats the winner as a sentence-cased string.

I provided a `docker-compose.yml` and convenient Python driver script so you can try it out quickly, and there's also a web-based demo where I bundled it with PGlite (WASM PostgreSQL) at https://tgies.github.io/megahal-sql/. These are provided for convenience, but you can also just run the schema initialization SQL and `SELECT megahal_converse('hello from hn.');`

Comments URL: https://news.ycombinator.com/item?id=47074812

Points: 1

# Comments: 1

New comment by tgies in "Show HN: The GPG Guide – Practical OpenPGP for 2026"

tgies — Thu, 12 Feb 2026 18:51:31 +0000

Thanks! I'll see what I can do about that.

Show HN: The GPG Guide – Practical OpenPGP for 2026

tgies — Thu, 12 Feb 2026 15:08:06 +0000

Most GPG documentation I could find was outdated -- O'Reilly 1995, No Starch 2006, countless websites from the mid 00s -- or scattered across dozens of blog posts that each covered one piece. I wanted a single reference that covered the full workflow with current tools and practices, so I had been keeping a bunch of text files in my homedir for a while. Recently I realized it was getting close to 60k words and I decided I should share it.

The guide covers GnuPG 2.5.x and Sequoia sq, defaults to Ed25519, and has three reader tracks: a minimal Git + SSH setup, a full YubiKey identity, and a high-assurance path for FOSS package maintainers and the like. 377 pages across 16 parts, with platform-specific instructions for Linux, macOS, and WSL.

Parts I–III are available as a sample download. I'd be really grateful for any feedback, as I have never written a book before and, frankly, have no business doing it.

Comments URL: https://news.ycombinator.com/item?id=46989765

Points: 2

# Comments: 2