Hi. I was trying to set up 2FA in my settings, where there is a button named “2FA installation link.” I right clicked on the button, copied the link, and put it into a QR code generator. I scanned it with Twilio Authy on my phone to add it. To my surprise, when I tried using it to log in, the generated codes simply do not work. I have 20ish entries on Authy and they all work, with the Lemmy accounts being the outliers. I have also tested the 2FA on my other account at feddit.nl, and it doesn’t work with Authy either.
So, I tried using Google Authenticator instead. I used it to scan the very same QR code, and it spits out different codes from those generated by Authy. The ones generated by GAuthenticator work, whereas the Authy ones don’t work. I wonder what the issue is?
Edit: grammar
I believe the issue is that Lemmy expects the codes to be generated using the SHA256 algorithm, while most generator apps use SHA1.
Ahhh, thanks! After closer inspection of the link
otpauth://totp/lemm.ee:randint?secret=[redacted, 64 characters]&algorithm=SHA256&issuer=lemm.ee, it does indeed specify SHA256. Looks like Authy just uses SHA1 regardless. Maybe I should switch back to GAuthenticator, but you know, Google…
