It appears that certificates generated on Ubuntu 22.04 are not being accepted by ATAK. I believe this is due to ATAK using a version of BouncyCastle (the SSL library) that needs to be upgraded to support PKCS12 files generated with a sha256 MAC.
I have filed an issue with ATAK here, and I'm looking at ways to attempt to generate p12 files using the sha1 algorithm. But as of now, it does not appear that python's cryptography libraries expose this as a configuration option.
It appears that certificates generated on Ubuntu 22.04 are not being accepted by ATAK. I believe this is due to ATAK using a version of BouncyCastle (the SSL library) that needs to be upgraded to support PKCS12 files generated with a sha256 MAC.
I have filed an issue with ATAK here, and I'm looking at ways to attempt to generate p12 files using the sha1 algorithm. But as of now, it does not appear that python's cryptography libraries expose this as a configuration option.