Diablo 3 CPK assets

[spamzilla]

So I'm trying to extract the contents of these .CPK files from DIablo 3. The Switch version uses some alternate format though and I haven't found any programs that are compatible with it. Does anybody know of this??

[ikskoks]

Can you upload a sample file?

[spamzilla]

This is one of the smaller ones. Most of them are at least 200MB. Common.cpk is 2.38GB.

ServerCommon.7z

Edited November 16, 2024 by spamzilla

[wq223]

On 2024/11/17 at AM12点53分, spamzilla said:

这是较小的文件之一。大多数文件至少有 200MB。Common.cpk 的大小为 2.38GB。

服务器通用.7z 3.67 MB · 4 次下载

The patch file you provide uses zlib compression and unknown compression (190D) headers, which might be better if someone could provide a specific compression type of 190D
The structure of the file seems a bit messy, I don't know if the index part is encrypted
Simply put, the file can be divided into four parts
Additional data (including magic number, version, number of files, unknown)
Unknown data (it should be the index part, but it's very messy)
File name part (the parsed file name corresponds to the previous number of files)
Compressed data block part (one data block includes multiple compressed files, each data block separated by a bunch of empty bytes)
Each compressed data includes an additional six bytes
4 byte unknown and 2 byte length
Compressing data is normal and can be decompressed
The problem is that some extra data represents a bit of error in the length of the data, resulting in a forced stop when the parsing is halfway.

[swiftlie]

Some info:
https://github.com/RedMadKnight/CPKReaderWV
https://github.com/RedMadKnight/D3CPKUnpack

[wq223]

42 minutes ago, swiftlie said:

一些信息：
https://github.com/RedMadKnight/CPKReaderWV
https://github.com/RedMadKnight/D3CPKUnpack

I checked the information you provided and found that this unknown compression type is LZ77? Then I wrote a script to decompress the lz77 compressed file, but it came out so strange, I'm not sure if they were right

[swiftlie]

I think it's more likely an encrypted chunk, not an other compression type.