nfc-anticol(1)

💖 nfc-anticol(1) — libnfc's examples 💖

okay bestie, gather round, because we're about to talk about anti-collision and it's genuinely so cool. this page lives in the libnfc's examples section of the manual, and it's giving "tiny tool, big brain energy" ✨

✨ NAME ✨

nfc-anticol — a demonstration of the NFC anti-collision command line tool, based on libnfc. yes that's the whole name, she's concise and she knows it 💅

🌸 SYNOPSIS 🌸

nfc-anticol

that's it. no flags, no args, no drama. just vibes 🦋

🎀 DESCRIPTION 🎀

so nfc-anticol is an anti-collision demonstration tool for ISO/IEC 14443-A tags, and the way it does this is by using custom constructed frames. periodt.

here's the tea: the very first frame has to be a short frame, which is only 7 bits long. seven. not eight. seven. 😭

and like... commercial SDK's often don't support sending frames that aren't a multiple of 8 bits (1 byte) long. which is a whole problem, because that makes it impossible to do the anti-collision yourself. so the developer has to rely on closed proprietary software and should just... hope it doesn't contain vulnerabilities during the anti-collision phase 🙈 (ngl that's not a vibe).

meanwhile, performing the anti-collision using custom frames could protect against a malicious tag that, for example, violates the standard by sending frames with unsupported lengths. so that's the slay part 🔥

⚠️ but bestie, listen — note that this is only a demonstration tool. it can not handle multiple tags, because real life anti-collisions with multiple tags generate "messy" bits which are neither 0 nor 1. so it's a one-tag-at-a-time situation, fr fr 💀

💀 BUGS 💀

found something cursed? please report any bugs on the libnfc issue tracker at:

https://github.com/nfc-tools/libnfc/issues

the maintainers wanna know, i promise 🫶

👑 LICENCE 👑

• libnfc is licensed under the GNU Lesser General Public License (LGPL), version 3.
• libnfc-utils and libnfc-examples are covered by the the BSD 2-Clause license.

(yes, "the the" — we keep the original's little quirks, no editing the queen 👑)

🌈 AUTHORS 🌈

Roel Verdult <roel@libnfc.org>

This manual page was written by Romuald Conty <romuald@libnfc.org>. It is licensed under the terms of the GNU GPL (version 2 or later).

and that's the whole page, bestie!! 🎀 this was libnfc, and the page is dated June 26, 2009 — a true classic, still iconic, still eating. mwah 💖✨🦋