Reverse HOTP support

[tlaurion]

@oxalica @ZenithalHourlyRate any interest into developing reverse HOTP inside of canokey? https://github.com/linuxboot/heads/pull/1671#issue-2291436187

Originally posted by @tlaurion in https://github.com/canokeys/canokey-qemu/issues/6#issuecomment-2106334309

Reference : https://github.com/Nitrokey/nitrokey-pro-firmware/commit/cff95754615a62d676e5cc9cafe85fcf351385b4

[tlaurion]

I guess first step would be https://github.com/canokeys/canokey-core/issues/83

@ZenithalHourlyRate @agreenbhm @dangfan @z4yx @z4yx @cnZary @cnZary @Yonghui-Lee Sorry to ping you all, but this would have important implications for the whole ecosystem, including emulated and hardware based security dongles.

Please contact me through linuxboot/heads project or through https://osresearch.net/community/

I see possible NLnet based funding by co-writing a grant application.

Thank you for your time.

[tlaurion]

Ping. Interest from your side would be needed first .

You can see past collaboration under grant from my side under https://github.com/linuxboot/heads/issues/1729 and ongoing https://github.com/linuxboot/heads/issues/1741

This is serious proposition, while canokey first need to show interest in doing effort.

Please poke me through https://osresearch.net/community/

[dangfan]

@tlaurion Please describe the usage scenarios for this feature, as the goal of Canokey is to serve as a personal identity authentication device rather than an HSM (Hardware Security Module). Understanding the context in which this feature would be used is essential for us.

Additionally, we welcome your pull request (PR) and look forward to your contributions.