2018-04-01 15:36:45 +02:00
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Implementation notes
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====================
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2018-04-29 21:41:34 +02:00
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Lightweight cleaning mode
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Due to *popular* request, MAT2 is providing a *lightweight* cleaning mode,
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that only cleans the superficial metadata of your file, but not
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the ones that might be in **embeded** resources. Like for example,
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images in a PDF or an office document.
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2018-04-01 15:36:45 +02:00
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Symlink attacks
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---------------
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MAT2 output predictable filenames (like yourfile.jpg.cleaned).
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This may lead to symlink attack. Please check if you OS prevent
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against them
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Archives handling
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-----------------
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MAT2 doesn't support archives yet, because we haven't found an usable way to ask the user
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what to do when a non-supported files are encountered.
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PDF handling
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------------
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MAT was doing some kind of rendering for PDF files, on a cairo surface, then
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printed it to a file. This kept the text selectable, but unfortunately, it
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didn't remove any *deep metadata*, like the ones in embedded pictures. This was
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on of the reason MAT was abandoned: the absence of satisfying solution to
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handle PDF. But apparently, people are ok with [pdf redact
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tools](https://github.com/firstlookmedia/pdf-redact-tools), that simply
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transform the PDF into images. So this is what's MAT2 is doing too.
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2018-04-03 21:45:05 +02:00
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Of course, it would be possible to detect images in PDf file, and process them
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with MAT2, but since a PDF can contain a lot of things, like images, videos,
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javascript, pdf, blobs, … this is the easiest and safest way to clean them.
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2018-04-01 15:36:45 +02:00
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Images handling
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---------------
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When possible, images are handled like PDF: rendered on a surface, then saved
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to the filesystem. This ensures that every metadata is removed.
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