How do I get the signature checksum of my APK that is signed with only the v2 scheme?

Question

I previously posted a question on how to get the signature checksum of my APK here: How do I get the signature checksum of my APK?

The answer is perfect if an app is signed with the v1 signature scheme or the combination v1/v2 signature schemes. (Jar and Full APK Signatures)

However, since my app will only be running on Android O or greater (it is a device specific app), I will only be signing it with the APK signature scheme v2 (v2 scheme).

I will be using EXTRA_PROVISIONING_DEVICE_ADMIN_SIGNATURE_CHECKSUM. See: https://developer.android.com/reference/android/app/admin/DevicePolicyManager.html for details.

How do I get the APK (v2) signature checksum of my app that I can use in my key/value pair for NFC provisioning a device owner app?

Deventer

Answer 1

To build on the example How do I get the signature checksum of my APK? you mentioned:

apksigner verify -print-certs [path to your apk] | grep -Po "(?<=SHA-256 digest:) .*" | xxd -r -p | openssl base64 | tr -d '=' | tr -- '+/=' '-_'

The "signature checksum" you're referring to is the URL-safe Base64 encoded SHA-256 digest of the APK's signing cert. apksigner verify --print-certs prints the various digests of the APK's signing certs, regardless of whether the APK is JAR signed, APK Signature Scheme v2-signed, or both.

apksigner is distributed via Android SDK Build Tools 24.0.3 and newer (except for 26.0.0 which is accidentally missing apksigner). https://developer.android.com/studio/command-line/apksigner.html

Solicitous

Just verified this method does work for v1 and/or v2 schemes! Thanks! – Deventer

my mac has a version of grep which does not support the -P flag. to get around that, i had to change the command a bit: i replaced grep -Po "(?<=SHA-256 digest:) .*" with perl -nle 'print $& if m{(?<=SHA-256 digest:) .*}' ( adapted from: https://mcmap.net/q/11488/-grep-p-no-longer-works-how-can-i-rewrite-my-searches ) – Whitefly

How can I do this on Windows? – Chichihaerh

i tried it with TestDPC but it returns a different code than the code provided in google repository example github.com/googlesamples/android-testdpc – Colonialism

How can I do this in Windows? – Thenceforward

Answer 2

a simple and good solution for windows users:

https://github.com/Mohsenabn78/enterprise-checksum-calculator/releases/download/checksum/enterprise-checksum-calculator-1.0.0.msi

install windows app > insert your apk path > calculate checksum

Newtonnext