Hi Lisa!
I need a C# program that can read the THF file: it must just tell me the
information of the screenshot
Here you find the needed files and all source code, including screenshot (see
last post)
https://csharpforums.net/threads/read-bytes-from-binary-file.9764/page-2#post-40107
I already have all decryption functions in C# working!
Sounds like you will already figure it out yourself :-)
There is no forum or anything where a living soul still can read this code :)
You're reading this problably one of my last hope out there
I suggest to ask more specific questions about specific code snippets,
because you can find most of the solution without help, I believe.
https://gitlab.com/twilight-cd.com/sourcecode-menu-twilight-9
> I want to make C# code that takes a THF file and extracts all TVF and
ZIP files from it
You probably have questions about THF.C, THF.H and THFTOOL.C?
THF seems to be an archive format with TVF docs and ZIP blobs
inside. You write that you already know how to open the ZIPs.
According to THF.H, the structure of THF is relatively simple:
https://stackoverflow.com/questions/71270954/how-to-properly-use-typedef-for-structs-in-c
https://en.cppreference.com/w/c/language/struct
The THF.H comments do not fully match THF.C, so:
4 bytes ID string
16-bit int (actually 2 bytes) version (of file format)
256 padding bytes (or rather 256-6 bytes, see THF.C!)
1 byte of "add"
64 bytes of key (more likely 64-1 bytes, see THF.C!)
("add" and "key" are scrambled, see thfOpenMainFile, a
loop does "subtract 82, then xor by 108" for each byte)
content is here, followed by a directory of 1 or more [items]:
[
13 bytes of file name (probably 12345678.abc plus a NULL byte)
32-bit long int offset (of content in THF, I guess)
32-bit long int size (of content)
]
(each [item] is scrambled by xor with a string, see THF.C)
and finally:
32-bit long int offset where the directory starts
(scrambled with xor 0x2b46c748 according to THF.C)
16-bit int number of directory items (not according to THF.H)
(scrambled with xor 0x2b46 according to THF.C)
So you have to read the LAST 6 (or 4?) bytes of the THF files to
know where the directory entries start and then each entry tells
you where in the THF you will find how many bytes of content for
one embedded file, for which also some file name is known. There
are no details about timestamps of the embedded files and there
are no subdirectories inside the THF. Pretty straightforward?
This is more or less what thfOpenMainFile and thfReadDirectory
are doing. Note that there is some descrambling added by THF.C!
The THFTOOL.C just wraps everything into some more or less
user-friendly command line tool, with wildcard matching.
For your project, you can probably ignore it (apart from some
small 0x3c 0xb1 0x43 trick thing) and only read THF.C, which
implements a number of basic functions to read from THF files.
You say you already figured out the other obfuscation code,
so you apparently have already translated parts of THF.C :-)
I suggest to print intermediate results and add plausibility
checks, to avoid crashes if you made mistakes in descrambling
and end up with offsets or sizes which do not make sense.
Cheers, Eric
PS: THF.C and THFTOOL.C probably crash if a THF contains or
claims to contain more than 200 embedded files :-p
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