Having the exposure database survive an Android Upgrade

[validev]

I need a way to have my exposure database survive an Lineage 16.1 -> Lineage 17.1 upgrade.

I don't want to lose my 14/14 rating and don't want to carry two devices with me for 4 weeks to have a seamless transition.

Any please don't say "out of scope". German corona app is the poster boy of all exposure noti. apps and you should be able to solve that together with Google devs.

[validev]

Ok .. just found the dumpsite you shove these kind of issues to .. nothing to show for since at least 18.6.20 .. so two weeks of keys will go down the drain I guess m(

[daimpi]

Are you talking about a switch to a new device or an OTA update? I don't think OTA updates delete any data, even updating to a new Android version should be save. Not entirely sure why LineageOS would be different.
If you want to transfer to a new device: that's currently not possible afaik unless you have root, because Google doesn't allow ENF data to be exported.

[validev]

Not talking about OTA. Clean flash including wipe of data partition. Hell, I'd be content with a howto to migrate the right files from /data/data/com.google.android.gms .. of course I have root.

[daimpi]

of course I have root.

great 👍

In this case migrating ENF + CWA data should be possible. I personally dunno how to do it but maybe @kbobrowski & @mh- have an idea? 🙂

[validev]

I started by dumping these dirs and files to another device, but I get a weird error msg from GMS, so I guess sth is missing

/data/data/com.google.android.gms/
app_contact-tracing-self-tracing-key-db
app_contact-tracing-contact-record-db
app_en_diagnosis_keys
app_en-exposure-result-storage-db
app_en-matching-request-db
app_en-attempted-keys-data-store-db

/data/data/com.google.android.gms/shared_prefs/contact_tracing_data_quality_record_db.xml

[validev]

not sure if it's enough to copy the ENF stuff though .. maybe CWA data is necessary, too, to keep the two components in sync?

[kbobrowski]

@validev I think you should copy over at least app_contact-tracing-self-tracing-key-db and app_contact-tracing-contact-record-db, first db contains data with your Temporary Exposure Key (so used if you want to notify others about your positive test), and second one contains received Rolling Proximity Identifiers, from which you can infer if you were in contact with infected person. Not sure how the first db will behave on fresh CWA install, second one should be not affected.

If you want to be on the safe side regarding being notified about exposure status, then make sure to have a backup of the app_contact-tracing-contact-record-db. Then you can infer exposure status even without CWA, using https://github.com/mh-/corona-warn-companion-android (this would require to copy this DB over to the phone after flashing), or even without any app using https://github.com/mh-/diagnosis-keys

[mh-]

What is the weird GMS error message?
One thing I noted was: concurrent writes to LevelDB directories were problematic.
So I ended up copying stuff back to the device only in Recovery Mode, when GMS was inactive. Then booted into Normal Mode, and GMS would just continue to use the databases I just wrote.

Of course, making CWA keep 14/14 would involve playing with the device’s local date while re-installing it.

[MikeMcC399]

My Samsung Galaxy preserved the Exposure Notification database when I upgraded Android from 9 to 10, but I didn't wipe the device or do a factory reset. The request from @validev requires that the device is wiped, so that is different.

The wishlist item #8 "Backup exposure history to transfer to new/reseted phone" would cover the needs if it gets implemented, which would normally need the cooperation of Google to do. So far there has been little transparency in Google's planned enhancements to the Android Exposure Notification System.

[validev]

What is the weird GMS error message?
"Ursache: 3 Etwas ist schiefgelaufen. Fehler bei der Kommunikation mit der Google Schnittstelle (39506)"

"com.google.android.gms.com mon.api.ApiException: 39506: com.google.android.gms.leveldb.LevelDbloErrorException: IO error: /data/user/0/com.google.android.gms/app_en-exposure-result-storage-db/LOCK: Permission denied"

It's worth noting that, of course, I looked at file/directory permissions. They don't seem to make any difference. The msg appears if the LOCK file is mode 600, 660, 666, even doesn't exist at all. All changes were made in Recovery Mode, with many rebootes inbetween - boy, Android dev. is cumbersome.

[mh-]

I don't think you will gain much from restoring app_en-exposure-result-storage-db- this is just used for generating the reports.
As @kbobrowski wrote, just restore app_contact-tracing-self-tracing-key-db and app_contact-tracing-contact-record-db - this should be possible in recovery mode. All the other databases will most likely be recreated by GMS without problems.

[validev]

Got it working now. Thanks for the support, guys.

[heinezen]

Hey everyone,

as @MikeMcC399 already pointed out, this feature request is very similar to corona-warn-app/cwa-wishlist#8. @validev Even if the issue is old, I suggest making an additional comment there, so that it's back on the radar again. I will close this issue now, since your problem seems to be resolved. Discussion about the feature request can happen in the wishlist issue.

Thanks.

---

Corona-Warn-App Open Source Team

[heinezen]

Duplicate of corona-warn-app/cwa-wishlist#8

[SAMUD]

I just saw this and want to give my 2cents:

I use "SwiftBackup" to backup my apps (including data) on a rooted phone. However, everytime I restore the Corona-app I am getting FC / Crashs when opening the app, so I need to wipe all data / cache and loose everything.

I remember in the beginning of the Corona-App I sometimes got a Error associated with the Database when this happened. Today, the app just freezed on the SplashScreen when I restored it from the Backup.

[daimpi]

@SAMUD by

I need to wipe all data / cache and loose everything.

you mean you delete the CWA data, or are you actually deleting the ENF data?

B/c if you're just wiping the CWA data, you don't actually loose much (except if you have a test pending) and the "0 days active" is just a temporary visual problem without any functional implications.

You can even get around this visual problem by using the instructions laid out here.

[fakerli]

Got it working now. Thanks for the support, guys.

What did you copy? I tried to copy app_contact-tracing-self-tracing-key-db and app_contact-tracing-contact-record-db and it worked. But it seems that any new contact won't be tracked anymore. Any ideas?
@validev

[mh-]

Can you copy in Recovery Mode? Then, after starting up again in Normal Mode, it should work.
(I did have problems when I tried to copy in Normal Mode, while the framework was running.)

[fakerli]

I did copy in recovery mode. It worked but it didn't fetch new data. I copied the files from 26th of october and since then I had no new data. If I delete both dirs it fetches new data from today.
@mh- : Which folders did you copy?

[mh-]

I copied those two folders, but I also remember that access rights (incl. SELinux specific rights) were important.

This is my restore script for the RPIs (for recovery mode):

#!/usr/bin/env bash

chmod 771 app_contact-tracing-contact-record-db/
chmod 600 app_contact-tracing-contact-record-db/*
source dbowner
source dbgroup
gtar --owner=$DBOWNER --group=$DBGROUP -cvf rpi.tar app_contact-tracing-contact-record-db/
adb push rpi.tar /data/local/tmp/
adb shell 'tar -C /data/data/com.google.android.gms/ -xvf /data/local/tmp/rpi.tar'

adb shell 'chown -R `cat /data/data/com.google.android.gms/app_contact-tracing-contact-record-db/dbowner`   /data/data/com.google.android.gms/app_contact-tracing-contact-record-db'
adb shell 'chgrp -R `cat /data/data/com.google.android.gms/app_contact-tracing-contact-record-db/dbgroup`   /data/data/com.google.android.gms/app_contact-tracing-contact-record-db'
adb shell 'chcon -R `cat /data/data/com.google.android.gms/app_contact-tracing-contact-record-db/dbcontext` /data/data/com.google.android.gms/app_contact-tracing-contact-record-db/*'
adb shell 'rm /data/data/com.google.android.gms/app_contact-tracing-contact-record-db/dbowner'
adb shell 'rm /data/data/com.google.android.gms/app_contact-tracing-contact-record-db/dbgroup'
adb shell 'rm /data/data/com.google.android.gms/app_contact-tracing-contact-record-db/dbcontext'

# ls -lZ /data/data/com.google.android.gms/app_contact-tracing-contact-record-db/
# u:object_r:app_data_file:s0:c512,c768 CURRENT

rm rpi.tar

[fakerli]

@mh- : It seems to work but i cannot gather new contacts. If I uninstall reinstall corona-warn, it starts from scratch but then i lose my old contacts.