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Comment by ysnp

1 day ago

>It would be "more secure" to have a per-application firewall that blocks particular apps from outbound traffic over certain networks or to certain destinations. This prevents a malicious app from consuming roaming data.

LineageOS can have that, at the owner's preference. Graphene explicitly forbids it.

Not sure what is meant by forbidding it? GrapheneOS provides per-app network access control via a user-controllable Network permission which is not implemented in AOSP or LineageOS afaik. They do not forbid using local firewall/filtering apps like RethinkDNS (to enforce mobile data only or Wi-Fi only iirc) and InviZible. They only warn that 'blocks particular apps from outbound traffic ..to certain destinations' cannot be enforced once an app has network access which makes sense to me.

>It would be "more secure" to allow backing up apps and all their data. This would mitigate the damage of ransomware. Graphene, again, forbids it (following google guidelines prioritizing the wishes of an app's developer over the device owner).

Contact scopes, storage scopes, the sensors permission and the network permission are examples that show precisely the opposite (GrapheneOS prioritises the device owner over the application developers). To my understanding, the backup app built-in to GrapheneOS even 'simulates' a device-to-device transfer mode to get around apps not being comfortable with data being exfiltrated to Google Drive. That being said, I understand they have plans to completely revamp the backup experience once they have the resources to do so.

They're referring to the leaky network toggles in LineageOS for different kinds of networks. GrapheneOS won't include that because it doesn't work correctly and gives people the false impression that it's going to stop apps communicating over those networks when it only stops most (not all) direct connections.

LineageOS has the same Seedvault backup system with the same limitations. There are few limitations left since Android 12's API level stopped apps opting out of all backups by redefining it as an opt-out of cloud backups and similarly redefined the file exclusions as only being for cloud backups. The new system supports very explicitly omitting files from device-to-device backups but it has to be explicitly specified that way and few apps do it. The problems with apps opting out of backups due to not wanting cloud backups for space, bandwidth or privacy reasons has been solved for several years now. It doesn't mean all app data is portable between devices, such as Signal encrypting their database with a hardware keystore key making it fundamentally impossible to do backups at a file level for it rather than using their own backup system.

See https://news.ycombinator.com/item?id=45562664 for a response to the rest of it.

  • No, I'm specifically referring to iptables-based firewalls (like AFWall), which Graphene does not allow the user to create and Lineage does (via root access).

    These are not an android VPN provider and allow blocking traffic based on the combination of source app AND DESTINATION SERVER ADDRESS.