I'm looking to implement USB monitoring for FIDO2 authentication through a custom Authorization Plugin, specifically for the below ones. This plugin applies to the following macOS authorization mechanisms: system.login.console — login window authentication system.login.screensaver — screensaver unlock authentication The goal is to build a GUI AuthPlugin, an authorization plugin that presents a custom window prompting the user to "Insert your FIDO key”. Additionally, the plugin should detect when the FIDO2 device is removed and respond accordingly. Additional Info: We have already developed a custom authorization plugin which is a primary authentication using OTP at login and Lock Screen. We are now extending to include FIDO2 support as a primary. Our custom authorization plugin is designed to replace the default loginwindow:login mechanism with a custom implementation. Question: Is there a reliable approach to achieve the USB monitoring functionality through a custom authorization plugin? Any guidance or pointers on this would be greatly appreciated.

What Has Been Implemented Replaced the default loginwindow:login with a custom authorization plugin. The plugin: Performs primary OTP authentication. Displays a custom password prompt. Validates the password using Open Directory (OD) APIs. Next Scenario was handling password change Password change is simulated via: sudo pwpolicy -u robo -setpolicy "newPasswordRequired=1" On next login: Plugin retrieves the old password. OD API returns kODErrorCredentialsPasswordChangeRequired. Triggers a custom change password window to collect and set new password. Issue Observed : After changing password: The user’s login keychain resets. Custom entries under the login keychain are removed. We have tried few solutions Using API, SecKeychainChangePassword(...) Using CLI, security set-keychain-password -o oldpwd -p newpwd ~/Library/Keychains/login.keychain-db These approaches appear to successfully change the keychain password, but: On launching Keychain Access, two password prompts appear, after authentication, Keychain Access window doesn't appear (no app visibility). Question: Is there a reliable way (API or CLI) to reset or update the user’s login keychain password from within the custom authorization plugin, so: The keychain is not reset or lost. Keychain Access works normally post-login. The password update experience is seamless. Thank you for your help and I appreciate your time and consideration

During SmartCard pairing the PIN prompt enables the OK button only on user provides a PIN of 6 digits. Is there a way to submit the empty PIN in this flow, where the custom CTK is used here (the custom CTK would take care of the PIN from the custom ctk code). I was able to do an empty PIN submit once the I've paired the user successfully at login, unlock and other cli tools. Is there a way to do the same during the pairing? Once the user has successfully paired with the SmartCard authentication with PIN, I was able to see most of the authentication flows was prompting for the PIN authentication like login, unlock, CLI tools like ssh, su etc., perhaps at few apps where it is still prompted with the Password instead of PIN examples, when I tried to launch Keychain Access app or Add a user from users&groups system setting. Is this expected behaviour?