Sony's Backup & Restore tool allows to back up application data, call logs, contacts, text conversations and other settings to an SD memory card or Google Drive. The different backup categories are stored in files coming in pairs such as SETTINGS and SETTINGS_meta, or CALL_LOG and CALL_LOG_meta.
I have used Backup & Restore to successfully transfer over my settings and data across a factory reset. However, I'm looking for a way to open and inspect the backup files without having to do an actual restore on the phone (which overwrites the current settings). For example, I have another set of Backup & Restore data from a previous Xperia phone, and I'd like to check the text messages that are stored in that backup set, without having to overwrite (or add them to) the messages I have on my current phone.
The _meta files are uncompressed XML files containing some information about the backup set, such as the time at which it was created, and a checksum. It also contains a tag "<isCompressed>1</isCompressed>". This is an example, my CONVERSATIONS_meta file:
<?xml version="1.0" encoding="UTF-8"?><root><deviceId>##TRUNCATED##</deviceId><clientVersion>2360324</clientVersion><checksum>4267047373</checksum><signature>##TRUNCATED##
</signature><modificationTime>1476100656386</modificationTime><initializationVector>UL5xoPlnxlqembfFIc6wvA==
</initializationVector><isCompressed>1</isCompressed><json_data/></root>
The CONVERSATIONS file itself, though, seems to be a compressed binary format. The first line is plain text and legible:
XT XML VERSION=00000001
but the rest is not readily decipherable, and I couldn't figure out how to do it. It's not a regular ZIP or GZIP file, at least not with standard headers (in contrast to the backup files created by PC Companion). Apparently, there is also no standardised binary XML format, everybody seems to be developing their own.
Has anyone had any success in opening and reading these files, or would know how to approach decoding them? Are they simply compressed, or also encrypted in some way?
