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trustcrypto
OnlyKey-Firmware
C2019–2019
trustcrypto / OnlyKey-Firmware

OnlyKey-Firmware

The OnlyKey Firmware runs on the OnlyKey itself and provides the core functionality of OnlyKey.

4Distinct people
4Mentions
0Explicit recommenders
244GitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

The OnlyKey Firmware runs on the OnlyKey itself and provides the core functionality of OnlyKey.

GitHub

Where it is used

No documented product use has been verified yet.

What people are saying

No recommendation phrase was found in the indexed comments.

No classified warning is attached to this page. Read the discussions before treating silence as approval.

Also in these discussions

Mentioned in the same Hacker News threads. That is not proof they are substitutes.

This week on Hacker News

Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 3:56:07 PM UTC.

No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.

Mentions over time

HN mentions by hour4 dated mentions

Observed mentions: 2019-12-26 15:16:12 UTC to 2019-12-27 02:43:21 UTC.

012019-12-26 15:00:00 UTC to 2019-12-26 16:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 commentsDec 26, 15:002019-12-26 16:00:00 UTC to 2019-12-26 17:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2019-12-26 17:00:00 UTC to 2019-12-26 18:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2019-12-26 18:00:00 UTC to 2019-12-26 19:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2019-12-26 19:00:00 UTC to 2019-12-26 20:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2019-12-26 20:00:00 UTC to 2019-12-26 21:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 commentsDec 26, 20:002019-12-26 21:00:00 UTC to 2019-12-26 22:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2019-12-26 22:00:00 UTC to 2019-12-26 23:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2019-12-26 23:00:00 UTC to 2019-12-27 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2019-12-27 00:00:00 UTC to 2019-12-27 01:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2019-12-27 01:00:00 UTC to 2019-12-27 02:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2019-12-27 02:00:00 UTC to 2019-12-27 03:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 commentsDec 27, 02:00

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
Dec 26, 15:002019-12-26 15:00:00 UTC2019-12-26 16:00:00 UTC101
Dec 26, 16:002019-12-26 16:00:00 UTC2019-12-26 17:00:00 UTC000
Dec 26, 17:002019-12-26 17:00:00 UTC2019-12-26 18:00:00 UTC000
Dec 26, 18:002019-12-26 18:00:00 UTC2019-12-26 19:00:00 UTC000
Dec 26, 19:002019-12-26 19:00:00 UTC2019-12-26 20:00:00 UTC101
Dec 26, 20:002019-12-26 20:00:00 UTC2019-12-26 21:00:00 UTC000
Dec 26, 21:002019-12-26 21:00:00 UTC2019-12-26 22:00:00 UTC000
Dec 26, 22:002019-12-26 22:00:00 UTC2019-12-26 23:00:00 UTC000
Dec 26, 23:002019-12-26 23:00:00 UTC2019-12-27 00:00:00 UTC101
Dec 27, 00:002019-12-27 00:00:00 UTC2019-12-27 01:00:00 UTC000
Dec 27, 01:002019-12-27 01:00:00 UTC2019-12-27 02:00:00 UTC000
Dec 27, 02:002019-12-27 02:00:00 UTC2019-12-27 03:00:00 UTC101

What Hacker News says

4 sources
I̶ ̶t̶h̶i̶n̶k̶ ̶i̶t̶'̶s̶ ̶u̶n̶l̶i̶k̶e̶l̶y̶ ̶f̶l̶a̶s̶h̶ ̶r̶e̶a̶d̶o̶u̶t̶ ̶p̶r̶o̶t̶e̶c̶t̶i̶o̶n̶ ̶i̶s̶ ̶e̶v̶e̶n̶ ̶s̶e̶t̶ ̶f̶o̶r̶ ̶t̶h̶i̶s̶ ̶p̶r̶o̶d̶u̶c̶t̶,̶ ̶a̶s̶ ̶i̶t̶ ̶a̶p̶p̶e̶a̶r̶s̶ ̶t̶o̶ ̶b̶e̶ ̶p̶r̶o̶g̶r̶a̶m̶m̶e̶d̶ ̶u̶s̶i̶n̶g̶ ̶t̶h̶e̶ ̶d̶e̶f̶a̶u̶l̶t̶ ̶A̶r̶d̶u̶i̶n̶o̶ ̶I̶D̶E̶.̶ And even if not, most are trivially attackable with hardware access, for example the ESP32 secure boot stack: https://limitedresults.com/2019/09/pwn-the-esp32-secure-boot... EDIT: Spoke too soon, claims Kinetis Flash Security is enabled (https://docs.crp.to/security.html#flashsecurity). This looks like it also disables JTAG access, so that is a plus ("8.3.2 Security Interactions with Debug", https://www.pjrc.com/teensy/K20P64M72SF1RM.pdf). Other than that, this C code has a lot of smell - for example, the repeated use of the ptr variable looks like what something som
Read the rest
eone unfamiliar with the C type system would use: https://github.com/trustcrypto/OnlyKey-Firmware/blob/c71d207...
In OnlyKey: Open-Source Alternative to YubiKey
I understand the Arduino model is different than other projects but we proudly use Arduino as it's open source and has lots of great features. As we use the Arduino model you can find that our source consists of the .ino you mentioned here https://github.com/trustcrypto/OnlyKey-Firmware as well as libraries here https://github.com/trustcrypto/libraries. Our code is reviewed by Codacy and yes, it does receive a grade of A. For the .ino grading you will need to look at the OnlyKey-Firmware Github repo and for the libraries check out the libraries library. I think some of the confusion in your comment here may be related to how Arduino works, all source can be found on Github.
In OnlyKey: Open-Source Alternative to YubiKey
It seems this is literally written in the horrible Arduino "everything in one huge file" style: https://github.com/trustcrypto/OnlyKey-Firmware/blob/master/... The funny thing is they have a "Source code reviewed by Codacy" badge on the readme claiming the code is grade A... but if you actually click through, of course Codacy didn't pick up the .ino file at all, so in fact nothing of substance is being reviewed. That .ino file wouldn't pass any style review... it's a mess. Anyway, looks like that firmware is incomplete (e.g. "onlykey.h" is missing). Just a quick scroll through the code gives me zero confidence in this thing, code quality wise. Someone who can't consistently indent code almost certainly isn't qualified to be writing security-critical software. Edit: looks like the rest of the code is here, and yeah, it doesn't inspire much
Read the rest
confidence (7000+ lines of code in okcore.cpp, ouch): https://github.com/trustcrypto/libraries/tree/master/onlykey
In OnlyKey: Open-Source Alternative to YubiKey

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