SecurityException for SCHEDULE_EXACT_ALARM about strongswan HOT 3 CLOSED

Yes, it is how it is.

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@tobiasbrunner the VPN application should refrain from requesting alarm permissions that require user interaction. This could potentially raise concerns about why the VPN application requires such permissions.

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The app requires accurate and disrupting timers (i.e. they have to trigger at an exact time even if the system tried to put the app in some kind of doze state) for NAT keepalives and other events (e.g. rekeyings). In particular for NAT keepalives connectivity from outside the NAT can't otherwise be guaranteed after a while because Android will delay regular timers etc. by up to 15 minutes after about 70 minutes of run time (could be even more restrictive nowadays, this was over 3 years ago when the new scheduler was added). That's pretty much useless for an event that has to trigger every 40 seconds, by default.

Edit: Note that there is a global option to ignore if the app is not on the power whitelist (if that's set, the user isn't prompted to add the app), but enabling that will obviously have an impact on the timers as described above.

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