Fairphone Open OS update killed XPrivacy, now my phone is useless, any help please?

I just installed the latest Fairphone Open OS update, Fairphone Open 17.04.0. Every time I update the OS I know that I have to re-install XPosed so that XPrivacy will still work - and I know that if I fail to do that, I can’t run any apps for fear that they will upload all of my private data to who-knows-where.

This time though, when I try to install XPosed, it says:

E:Zip signature verification failed: 1

…and it refuses to install it. This has been freshly downloaded using the XPosed Downloader, xposed-v87-sdk22-arm.zip.

So now my phone is unusable until I fix this. Of course, there’s no backup, since it’s not possible to make full backups of an Android phone (TWRP just pretends). Is there any way out of this mess? My next best option is to just delete every app so I can at least make phone calls.

I just realised: the other thing that happened since I last updated the OS is that I switched on encryption. That’s likely to be it right? You can have XPrivacy, or encryption, but not both?

It turns out that in Android, there’s no way to remove encryption once it’s been switched on.

(And this encryption is entirely pointless anyway: https://blog.cryptographyengineering.com/2016/11/24/android-n-encryption/)

So I’m screwed right? The phone is useless until I can figure out how to backup all my data one file at a time, if I can, and then do a factory reset.

I think there is an option in TWRP to disable signature verification. This is a potential security risk, but I would risk it if the file comes from a trusted source.
You sometimes get these problems when whoever created the package forgot to add a signature to the zip and then the verification process fails because of this.

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Oh thank god for that, yes, under settings, “zip file signature verification”. There’s still some warnings about being unable to read “data”, which I guess is because of the encryption, but it still applies Xposed OK. And now Xposed Installer tells me “Xposed Framework version 87 is active”.

This all makes me acutely conscious of the fact that I’m running without a backup. That’s a huge flaw in the whole system, maybe the tipping point to make me switch back to an iphone.

…where you can just dream to have something like XPrivacy

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What do you mean by that? I use TWRP backups a lot and I found them really convenient, they allow me to switch easily between available OS (in a couple of minutes I can load my image of OpenOS, SailfishOS, UbuntuTouch and even FirefoxOS) and to make external backup by copying the whole folder to my laptop or USB stick. This is way more convenient than the “adb backup” command-line, in my experience.
Additionally, for an app-by-app backup I use Titanium backup.

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For anyone who relies on TWRP for backups, you really should have this article memorised. The title says why: “What is EXCLUDED from a TWRP backup?”

https://twrp.me/faq/backupexclusions.html

And here you can read the stories of dozens of people who thought selecting “create backup” would create a backup, and lost precious data as a result:

I almost have sympathy for the TWRP developers on this. It’s a really hard problem and Android doesn’t lift a finger to make it any easier. The Android usage model is “Google owns your data - if you want to read it, just ask Google to lend it back to you.”

Yes, you are right, the /data/media is not included in backups. But (as I understood) the spirit of this /data/media is to have somehow an “internal SD card” that is considered like a external media but on the phone internal storage. Similarly, I would understand that TWRP doesn’t backup the external SD card either…

When I switch from one backup to another, this is not a concern as TWRP exclude also the /data/media/ from the wiping process. The only issue is when one wants to do a full wipe without being aware of that. (and this should have been more explicit, like a warning message displayed when the backup is done)

I agree with you when you say this is not optimal… However, for me this is not a sufficient reason for not using TWRP at all, or to conclude that the whole Android experience doesn’t worth it and that you want to go back to iPhone :wink:

Regards,
Olivier

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Where’s the big problem? What TWRP will not backup can still be synced with MyPhoneExplorer or backed up with Titanium Backup? Of course, you still have to remember to do that.
I agree that it’s not pretty, but every system has its flaws.

Probably, as the TWRP version that currently comes with Fairphone Open OS cannot decrypt. But the latest version of TWRP can, and you can even boot it without installing it.

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What TWRP will not backup can still be synced with MyPhoneExplorer or backed up with Titanium Backup?

The answer to that question is “no”. Like TWRP, Titanium Backup doesn’t back up internal storage. At least if it can, I can’t figure out how, and if I can’t figure out how to make a backup with my backup software it’s not very good backup software.

Here’s the FAQ:

http://www.titaniumtrack.com/kb/titanium-backup-kb/titanium-backup-technical-faq.html#backup-what

A responsible developer would answer the question “What CAN’T Titanium Backup back up?”. That question is not answered. But it does say “Most (nearly all) of your phone’s settings and data.” That hint is enough reason to avoid Titanium Backup.

Perhaps I can manually copy files with MyPhoneExplorer, but my experience is that filesystems are complicated and operating systems hide things. A backup is more than just making a copy of files. A real backup means:

  • Make a backup
  • Put your phone in a shredder
  • Buy a new phone
  • Restore the backup
  • Bytes lost: zero

I’m pretty sure any normal person would agree that that’s what “backup” means. But Android apps feel free to call themselves “backup software” when they don’t do that. That means I can’t just hunt for “backup software” to find a way to make a backup. Everyone, every software website, every Android blog, every commenter on this forum, ends up suggesting something that won’t do what a normal person would expect backup software to do.

It’s not necessarily anyone’s fault in particular, but it’s a very bad situation.

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I can totally agree to your assessment of the situation, but where is the perfect solution?
If there is no perfect solution, wouldn’t it be reasonable trying to get as close as possible instead of making no attempt at all because it doesn’t look pretty conceptually?

TWRP and MyPhoneExplorer do the trick for me. I’ve had my fair share of restored backups with that combo when I fiddled around with EFIDroid to no avail, and the restores worked :slight_smile:

And sorry about mentioning Titanium Backup, I don’t use it, but it gets recommended a lot.

Actually, if one doesn’t change anything in /system, a TWRP backup isn’t even necessary.
Since only recently twrp started to support encrypted /data, I only had titanium backups. While I was switching different OSs, whenever coming back to Android, all I need to do was installing the os, installing titanium and loading the backup, in order to have the phone as before.
I don’t have any data though on the phone, as all synced. The moment I create files/contacts etc. they get uploaded to my owncloud installation.

So for me titanium worked quite well as only backup solution, to have my phone looking and behaving as before within a few minutes, after reinstalling Android.

But I totally agree. It would be nice to just create one backup file that includes the entire system and data.

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I can totally agree to your assessment of the situation, but where is the perfect solution?

If there is no perfect solution, wouldn’t it be reasonable trying to get as close as possible instead of making no attempt at all because it doesn’t look pretty conceptually?

I’m very glad you asked both of those questions :slight_smile:

Apple Time Machine is the existence proof for dependable, easy-to-use consumer-grade backup software. It ticks all the boxes. Anything else aspiring to be consumer-grade backup software should study Time Machine inside and out before getting started.

Failing that, rsync is the standard solution for the technically proficient to produce a complete, correct, restorable backup of all data and metadata. The problem is that you need to build up quite a complicated recipe to get it right, especially if you have tricky partitions and odd data caches like Android. If you get it wrong, you have no backup. I can use rsync on a Linux server, but it’s too risky to roll my own solution for Fairphone. It takes someone with in-depth knowledge of that specific environment.

The wider point though: backup software is not an appropriate field for a “do your best and learn something new!” attitude. Like encryption software, a flawed implementation is worse than no implementation at all. Seatbelts don’t reduce injuries as much as they should, because the sense of security causes people to take more risks. Flawed backup software is like a cardboard seatbelt.

If you produce a consumer-targeted backup product that claims to make a backup but does not, in fact, make a backup, you’re doing more harm than good. You should stop, or at least slap “alpha software do not use” stickers all over it. Do not waste time attempting to build a product when you know you will never have the resources to do it properly. Save your time and energy for something that can make the world a better place.

In the Android world, all the oxygen in the room is sucked up by the two standard backup solutions: Google’s cloud, and “nothing”. Almost every Android user is happily using one of those, largely because almost no users of IT give any thought to backups in the first place. I have a lot of sympathy for people trying to do better. But it’s gonna take either a lot of deep strategic thinking or a big pile of cash to make something that’s better than nothing. Sorry.

My practical proposal for right now: all the solutions we have should change their names to something other than “backup”. “Migration assistant” maybe, based on how people here actually seem to use them. If they evolve into genuinely good backup solutions, only then consider changing back.

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I don’t know any tools of the Apple universe, so I need to ask for clarification: Does Time Machine backup only your data or the entire system, including all changes and tweaks you made to a rooted/jailbroken system?

I am asking this, because the discussion has been about using TWRP for backup, as well as having a modified system with xposed installed.
As far as I understand this has been the great advantage of making TWRP backups over data backups, that it creates a snapshot of your current system, including all the modifications and tweaks you made to your system. Most other software/apps rather focus on backing up your data only. As I wrote above, these work quite well in my opinion (and with my setup) if you haven’t made many modifications to the system, as you can have your phone set up again within a couple of minutes; yet, as you rightfully pointed out, not all your system modifications would be covered. Despite the shortcoming you mentioned above, I think this is what makes the TWRP backup a useful tool, as it also creates a snapshot of your system. I also think this is actually what TWRP backup is mainly made for, rather than a simple data backup. It helps you when switching between OS, so you quickly get back the system you had installed before. Also handy when you are testing certain things, like another OS.

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I think @matthew_exon was giving examples of how to correctly go about backups in general with Time Machine and rsync rather than focussing on smartphones alone.

As far as I know Time Machine doesn’t backup iOS devices, only macOS. iTunes can to some extent do local backups of iOS devices (or only data?).
But I have no Apple devices so I’d gladly accept more input about that.

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