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Save pwlin/8a0d01e6428b7a96e2eb to your computer and use it in GitHub Desktop.
| https://code.google.com/p/android/issues/detail?id=32696#c5 | |
| If you have a certificate that is not | |
| trusted by Android, when you add it, it goes in the personal cert store. | |
| When you add a cert in this personal cert store, the system requires a | |
| higher security level to unlock the device. But if you manage to add your | |
| cert to the system store then you don't have this requirement. Obviously, | |
| root is required to add a certificate to the system store, but it is quiet | |
| easy. | |
| Here is how to do it : | |
| 1 - add your cert normally, it will be stored in your personal store and | |
| android will ask you a pin/password... Proceed | |
| 2 - With a file manager with root capabilities, browse files | |
| in /data/misc/keychain/cacerts-added. You should see a file here, it's the | |
| certificate you have added at step 1. If you can not find it in that path, look in /data/misc/user/0/cacerts-added/ | |
| 3 - Move this file to system/etc/security/cacerts (you will need to mount | |
| the system partition r/w) | |
| 4 - Reboot the phone | |
| 5 - You are now able to clear the pin/password you have set to unlock the | |
| device. | |
| I Think that this will only work for Root or Intermediate CA. | |
| I got the idea by reading this : | |
| http://nelenkov.blogspot.fr/2011/12/ics-trust-store-implementation.html |
This is how I did it on my Sony Xperia z5 Android 10 (rooted)
- Install MTIMPROXY
cd ~/.mitmproxyand thenopenssl x509 -inform PEM -subject_hash_old -in mitmproxy-ca-cert.cer | head -1adb rootadb shellmount -o rw,remount /- Open a vim in the shell and copy paste the content of file in step 2.
- Save the file in
system/etc/security/cacerts/FILENAME.0find the file name in step 2 chmod 644 system/etc/security/cacerts/FILENAME.0mount -o ro,remount /- Reboot
- Open MITMPROXY on PC and set the proxy on android.
Now I can see all HTTP or HTTPS traffic. The only traffic that I can not see is the CA-pinned traffic (Facebook for example) for those you need to decompile APK, change the res file, compile it again and install it on your android device.
For Magisk users I can also recommend this addon, if you only have your own user certificates. Technically it should also be possible to create an own Magisk Module only containing your certificate, but this was easier to setup quickly.
5 - Move the cert. Replace "cert.0" with whatever the filename is. eg
c7451f0d.0adb ls /data/misc/user/0/cacerts-added adb pull /data/misc/user/0/cacerts-added/cert.0 adb push cert.0 /system/etc/security/cacerts/
@vsTerminus I'm stuck on the 3rd command from step 5. Getting this error:
adb: error: failed to copy '13e3ab67.0' to '/system/etc/security/cacerts/13e3ab67.0': remote couldn't create file: Read-only file system`
When I run adb root it says 'adbd is already running as root'.
Any help will be appreciated.
Thanks.
@sabbirrahman I guess you forgot to remount root as read-write.
# mount -o rw,remount /
Some of you guys are missing a critical detail. Since Android 10, and possibly earlier, Google has gone with a ”system-as-root” approach. This means you cannot remount the /system position as read/write, and you can't modify it directly, even as root. The magisk add-ons mentioned are now pretty much the only game in town.
Fsck Google
user certs location in my device:
/data/misc/user/0/cacerts-added
Meizu 16s also located here. Thanks :)
you can read System CA on Android Emulator from mitmproxy:
3. Insert certificate into system certificate store
Now we have to place our CA certificate inside the system certificate store located at /system/etc/security/cacerts/ in the Android filesystem. By default, the /system partition is mounted as read-only. The following steps describe how to gain write permissions on the /system partition and how to copy the certificate created in the previous step.
Instructions for API LEVEL > 28
Starting from API LEVEL 29 (Android 10), it seems to be impossible to mount the "/" partition as read-write. Google provided a workaround for this issue using OverlayFS. Unfortunately, at the time of writing this (11. April 2021), the instructions in this workaround will result in your emulator getting stuck in a boot loop. Some smart guy on Stackoverflow found a way to get the /system directory writable anyway.
Keep in mind: You always have to start the emulator using the -writable-system option if you want to use your certificate. Otherwise Android will load a "clean" system image.
Tested on emulators running API LEVEL 29 and 30
Instructions
- List your AVDs:
emulator -list-avds(If this yields an empty list, create a new AVD in the Android Studio AVD Manager) - Start the desired AVD:
emulator -avd <avd_name_here> -writable-system(add-show-kernelflag for kernel logs) - restart adb as root:
adb root - disable secure boot verification:
adb shell avbctl disable-verification - reboot device:
adb reboot - restart adb as root:
adb root - perform remount of partitions as read-write:
adb remount. (If adb tells you that you need to reboot, reboot againadb rebootand runadb remountagain.) - push your renamed certificate from step 2:
adb push <path_to_certificate> /system/etc/security/cacerts - set certificate permissions:
adb shell chmod 664 /system/etc/security/cacerts/<name_of_pushed_certificate> - reboot device:
adb reboot
I managed to put the cert (.0 file) in /system/etc/security/cacerts/ using a Magisk module, but still can't get it to work, permissions seem to be the same for all certs there
I managed to put the cert (.0 file) in /data/misc/user/0/cacerts-added. By doing that it will recognize as a user-imported certificate, and no remount/reboot is necessary. adb root is still necessary though.
Note: It works right away by using adb push from the host machine. If you use adb shell cp from another location inside the device, you'll need to chmod the cert file for it to work.
Is it possible to retain certificate added to system store after unrooting?
Tested on API 28
adb root
adb disable-verity
adb reboot
adb root
adb remount
adb push FILENAME.0 /system/etc/security/cacerts
adb shell chmod 664 /system/etc/security/cacerts/FILENAME.0
Has anyone managed to do this with AVD with Google Play (NOT Google API's) and Android 11 installed? I realize I've sort of shot myself in the foot here, but if anyone knows of a way to root such a device please let me know using Android Studio.
You can root the avd with https://forum.xda-developers.com/t/script-rootavd-root-your-android-studio-virtual-device-emulator-with-magisk-android-13-linux-darwin-macos-win-google-play-store-apis.4218123/ and do most of the commands with adb after running "su".
For future visitors: this method doesn't work for Android 14 (aka API level 34) as certificates are now loaded from /apex/com.android.conscrypt/cacerts (instead of /system/etc/security/cacerts) . This new path corresponds to the mounted com.android.conscrypt APEX container, which is signed and immutable.
See here for more information: https://httptoolkit.com/blog/android-14-breaks-system-certificate-installation/ (mirror)
Edit: see this comment for a working fix.
Well, always not easy works.
I failed almost at very first time when trying to use certificates that pushed to system trust store via Magisk Overlayfs modules, but always at first, most of apps don't accept them.
Quite tiring and boredom.
Btw, the certificates that installed by user, with der format, but the format of all certificates in system root certificate store is "pem" with plaintext contain the cert in base64 itself and its text below with sha1 fingerprint.
I tried to mimic all of these things but still failed 😪
Yeah this thing is ancient by now. With system-as-root, the only way to install your own system level certificates is with the magisk overlay. But nothing accepts them anymore because they don't have a trusted verification server, which is nigh impossible to get without getting your root ca fully trusted anyway. You can still install them as user certs without root, but then you have to deal with the 'network may be monitored' warning.
I abandoned my personal CA and just switched all my stuff over to letsencrypt.
Good news: Adguard found a solution to make their custom cert work on Android 14 i.e. /apex/com.android.conscrypt/cacerts.
See here: AdguardTeam/adguardcert/module/post-fs-data.sh#L50-L73
Just replace Adguard's certificate with your own certificate in this module and you're good to go.
See also this module for an alternative: nccgroup/ConscryptTrustUserCerts
It didn't work for me but it may work for you (or could be fixed in the future).
Good news: Adguard found a solution to make their custom cert work on Android 14 i.e.
/apex/com.android.conscrypt/cacerts.See here: AdguardTeam/adguardcert/module/post-fs-data.sh#L50-L73 Just replace Adguard's certificate with your own certificate in this module and you're good to go.
See also this module for an alternative: nccgroup/ConscryptTrustUserCerts It didn't work for me but it may work for you (or could be fixed in the future).
@devnoname120
pls tell me how to replace adguard module to reqable and httpcanary ca certificate
i tried but didn't understand anything
@Things22 I did it brother.
For httpcanary, I did it hurray!
Just download the zip from here https://github.com/AdguardTeam/adguardcert/releases/
Then open it and go post-fs-data.sh and you need to just change two things. Look for something like this AG_CERT_HASH , AG_CERT_FILE and edit both of them to this.
AG_CERT_HASH=87bc3517 AG_CERT_FILE=/data/local/tmp/87bc3517.0
Make sure to copy your root certificate to /data/local/tmp
And then install that zip to magisk as you do for modules.
Reboot and done.
+1 Thanks a bunch.
This helped a lot with Let's Encrypt rolling over to their ISRG Root X1 cert and old android machines.
@Nattle @RevealedSoulEven could you tell how it worked for you
i am testing on android 14 samsung real device i followed the steps and edit the both variable but getting Error
unZip Error
@Nattle @RevealedSoulEven could you tell how it worked for you i am testing on android 14 samsung real device i followed the steps and edit the both variable but getting Error unZip Error
this: https://xdaforums.com/t/magisk-module-unzip-error.4503395/ works for me.
You need to be careful to not include an dir in the zip file, after editing, only zip files in unzipped dir instead of zip the dir.
@Sudo989 No.
I adopted the Adguard module and wrote Cert-Fixer for installing custom CA certificates.
The module copies user certificates installed on the phone to system certificate store during boot. I've tested and verified it on an AVD emulator Pixel 8, Android 15 (API 35) and Pixel 8, Android 14 (API 34).
No intense testing was done on this. So if you get an error, copy the logs from /data/local/tmp/cert-fixer.log and ping me.
I have compiled some methods here, https://pswalia2u.medium.com/install-burpsuites-or-any-ca-certificate-to-system-store-in-android-10-and-11-38e508a5541a