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Fail to decompress these data streams ("brcm-lzma" method?)

Open XVilka opened this issue 4 years ago • 5 comments

Unpacking the data, and noted that some streams can't be unpacked with lzma-rs, see the attached files of the compressed and uncompressed chunks.

lzma_alt_samples.zip

The chunks were successfully unpacked with this library instead: https://github.com/firmadyne/sasquatch/tree/master/LZMA/lzmalt

The algorithm itself seems came out of the Broadcom LZMA modification.

XVilka avatar Jan 22 '20 08:01 XVilka

Could you document how standard this "Broadcom modification" is?

I won't have much time to investigate this in the following weeks, but feel free to send a pull-request to support this variant of the algorithm (preferably using a decoding option if there's something non-standard involved).

gendx avatar Jan 24 '20 14:01 gendx

I don't think it's a standard one, but quite common among compressed firmware images.

XVilka avatar Mar 10 '20 05:03 XVilka

@XVilka are you able to share how you decompressed these?

voltagex avatar Dec 27 '21 05:12 voltagex

@voltagex you can see the https://github.com/firmadyne/sasquatch/tree/master/LZMA/lzmalt

XVilka avatar Dec 30 '21 07:12 XVilka

@XVilka yes, this creates a library, not a program - did you write something to use this library to decompress the data?

voltagex avatar Dec 30 '21 07:12 voltagex