Rename 'Detect Reader' to 'Extract MF Keys'

[bettse]

What's new

• Rename 'Detect Reader' to 'Extract MF Keys'

The inaccurate name of this has been a major headache for those trying to help people with NFC. It also tempts unfamiliar users to try it, which can in turn get them into trouble.

Verification

• Launch NFC app, look at menu, see new name

Checklist (For Reviewer)

• PR has description of feature/bug or link to Confluence/Jira task
• Description contains actions to verify feature/bugfix
• I've built this code, uploaded it to the device and verified feature/bugfix

[nvx]

Does "Collect MFC Nonces" fit in the UI?

[bettse]

Does "Collect MFC Nonces" fit in the UI?

I didn't try, I was more concerned with getting something out ASAP since I'd been so delinquent in doing it before. I felt the new name would certainly fit where the old name did. Always possible someone does a follow up PR to further improve the name (or the code references)

[skotopes]

@bettse @noproto @nvx

@zhovner proposed idea that Collect Nonces is a part of Extract reader keys/Sniff reader keys/Sniff MF keys process.
And it make sense to ship MFKey with firmware and integrate into NFC flow so this function will be complete.

We can make it happen in next sprint(starting next week). Do you guys have any thoughts about it?

[noproto]

@bettse @noproto @nvx

@zhovner proposed idea that Collect Nonces is a part of Extract reader keys/Sniff reader keys/Sniff MF keys process. And it make sense to ship MFKey with firmware and integrate into NFC flow so this function will be complete.

We can make it happen in next sprint(starting next week). Do you guys have any thoughts about it?

Integrating MFKey's functionality into the NFC app would be the friendliest process for users (it would be completely opaque: NFC app->Read->Done, NFC app->Collect keys from reader->Done). The biggest obstacle I see to achieving it is the available memory in the NFC app. The NFC app is using almost all of the available memory, even when it is on the main menu. There is 20% of the available RAM remaining - about 30 KB. To integrate it with the NFC app we'll need 60KB at least (6 min avg - slow) up to 110KB (3 min avg - fast). I haven't analyzed the memory usage of the NFC app but I imagine some of the functionality could be exported into FALs and loaded on demand to drop total memory usage. I wouldn't expect the main menu by itself to consume 100 KB of RAM.

For specifically this feature, on the nonce collection side, we can eliminate duplicate nonces from the current implementation of Collect Nonces/Extract reader keys/Sniff reader keys/Sniff MF keys so the user is not prompted to recover keys for nonces which do not result in new keys. MFKey already provides this function: key_already_found_for_nonce_in_dict, so we'd just move it up earlier in the process. The scene where nonces are collected can inform the user how many duplicate nonces were collected ("Duplicate:"), and how many are new ("New:"), so users understand if they are making progress.

Regardless, I'm sure @bettse and @nvx 's concerns are the label itself. There is an NFC/RFID Field Detector application which seems to closer align with the label of "Detect Reader", but without any further protocol analysis or fingerprinting.

[bettse]

I’m concerned with the label, and getting it done promptly.  These other ideas can always be added on top of this.  A bird in the hand is worth two in the bush.

[skotopes]

@noproto we'll stop nfc app before opening mfkey. memory shouldn't be a problem.

@bettse agree, we'll merge this PR first. The only change we propose is to change name from Collect Nonces to something that will be understood by users without help(Extract reader keys/Sniff reader keys/Sniff MF keys process).

[bettse]

The only change we propose is to change name from Collect Nonces to something that will be understood by users without help(Extract reader keys/Sniff reader keys/Sniff MF keys process).

Done!

[nvx]

@noproto we'll stop nfc app before opening mfkey. memory shouldn't be a problem.

@bettse agree, we'll merge this PR first. The only change we propose is to change name from Collect Nonces to something that will be understood by users without help(Extract reader keys/Sniff reader keys/Sniff MF keys process).

It's probably worth avoiding the term sniff as that usually means passively sniffing an interaction with a card/reader, while doing the reader part of a mfkey32 attack is an active process. "Extract reader keys" seems workable, although some people seem to think that the media access keys is the key to open a door but not sure what better wording could be on that front that's both self explanatory while avoiding people jumping to incorrect conclusions.

[skotopes]

@nvx Extract MF Keys then?

[nvx]

@nvx Extract MF Keys then?

Ooh I like it!

[bettse]

new name pushed

[mishamyte]

Meaningful rename, but IMO Extract MFC keys is more conceptually right, cause that feature isn't related to other Mifare family chips

[bettse]

Unfortunately a bit late to re-litigate. Perhaps open a new PR with that change? I agree it does improve the accuracy of the label.

[mishamyte]

Yeah, unfortunately I completely missed that topic in time.
It could be created separately, but docs will need to be updated one more time