I am trying to decryt cloud storage files. Those files have a header that I want to skip.

For example, this file is composed of [cloud storage header + salt + content + cloud storage footer]. Lets say salt is 'SALT'.

------WebKitFormBoundaryMpzAvNgQ8HhW5A8i
Content-Disposition: form-data; name="file"; filename="blob"
Content-Type: application/octet-stream
SALTáB†nJÎÆBÂÀ?ó“´ZM¥SJz·xM×±È(ºKéGw#²ÇœQëKBt'ø%ÄkæsUA-h]aWA¯(•Ÿ€Ø&©€
------WebKitFormBoundaryMpzAvNgQ8HhW5A8i--

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