keymaster uses COMPRESSED secp256k1 public keys.

BIP38 encryption includes a calculation of a bitcoin address and implicitly requires UNCOMPRESSED keys.

Replace keymaster/cryptils package with the updated bitsanity/cryptils project library.

Root cause: wg/scrypt#50

Pure-java implementation of scrypt has poor performance so the author also includes shared-object binary files to be used through JNI:

lib/x86_64/darwin/libscrypt.dylib
lib/x86_64/freebsd/libscrypt.so
lib/x86_64/linux/libscrypt.so

Building the APK throws
com.android.tools.build.bundletool.exceptions.BundleFileTypesException$FileUsesReservedNameException: File 'root/lib/x86_64/darwin/libscrypt.dylib' uses reserved file or directory name 'lib'.

keymaster only uses the pure-java part so the offending objects can be removed from the jar.

Google rejected due to violation of ad policy. The app relies on a separate app called ZXIng available free/open-source from the Playstore. The app tries to run this using the Intent mechanism, and if it is not found it redirects the user automatically to the ZXIng on Play which is mislabeled "Shopping" and this is the source of confusion.

Update to make it more obvious to the user this dependency and redirect them to Play by choice.

Keymaster does not set the Base64.NO_WRAP flag in call to Base64.encodeToString() so the result can contain newlines.

This should be fixed in keymaster but also kgagent and gatekeeper implementations should be prepared to strip out whitespace and newlines.