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wattostudios, posted Mon Aug 21, 2017 12:14 pm (25784)

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Hi guys,

Arma 3 (and the standalone mod/game Argo) use mostly *.pbo archives which are well understood, having the same format as in older games Arma and Arma2.

In Arma 3 and Argo, however, there are a few other archives with the extension *.fbo which look to be encrypted versions of *.pbo archives. Would anyone care to take a crack as seeing what's in them?

Here are some *.pbo and *.fbo archives to investigate. Each archive (pbo and fbo archives) have their own key files, although the PBO keys aren't used in the archive. Presumably the FBO key files contain the key needed for decryption? There is also a separate key file for the whole game (argo.bikey)

https://drive.google.com/open?id=0B7gEf ... ERwa3RyRk0

If anyone could assist with the decryption, that'd be great. Let me know if you need any further information.

For reference, the structure of the PBO archives are...

Code:

// ARCHIVE HEADER
  1 - null
  4 - Header (sreV)
  16 - null
  
  6 - Prefix Header (prefix)
  1 - null Prefix Header terminator
  X - Prefix Name
  1 - null Prefix Name terminator
  
  7 - Product Header (product)
  1 - null Product Header terminator
  X - Product Name
  1 - null Product Name terminator
  
  7 - Version Header (version)
  1 - null Version Header terminator
  X - Version
  1 - null Version terminator
  
  1 - null End Of Archive Header terminator

// DIRECTORY
  // for each file
    X - Filename
    1 - null Filename Terminator
    12 - null
    4 - Unknown
    4 - File Length

  22 - null (ie. a completely null entry)

// FILE DATA
  // for each file
    X - File Data

Thanks.

ComatoseBadger, posted Wed Nov 08, 2017 9:44 pm (29884)

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I would be interested in this as well