Hi Harald,
I'm thinking of starting a project that would allow us to
- perform SIM and USIM card pre-personalization
 - read/dump and explore [U]SIM contents interactively
 - perform SIM card simulation
 The idea is to start with some generic data structure that can represent the filesystem tree (DFs, EFs) and their "external" properties, i.e. file type, size, permissions, FID, SFID, etc.
This data structure could also have the actual file content associated with each EF.
you might wanna have a look at oFono source code. At least for reading EF and parsing them we have extensive support. Check src/simutil.[ch] and src/simfs.[ch].
Same if you care about the SIM Toolkit support. It has support for parsing the majority of data structures you find there.
Regards
Marcel