function to check for AES-encryption

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   Hi!

I want to wrote a function which detects if a document is aes-encrypted. I've found few pieces of circumstantial evidence:

I want to take the filestream searching for:
( "CFM/V2" or "CFM/AESV2" or "CFM /V2" ) and ( /Length 128 ).

What are the opinions here? Is this stable and save enough or will i miss many aes-documents?

Best regards,
Ingo

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Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3524	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Topic: function to check for AES-encryption Posted: 02 Jul 07 at 7:13AM
	Hi! I want to wrote a function which detects if a document is aes-encrypted. I've found few pieces of circumstantial evidence: I want to take the filestream searching for: ( "CFM/V2" or "CFM/AESV2" or "CFM /V2" ) and ( /Length 128 ). What are the opinions here? Is this stable and save enough or will i miss many aes-documents? Best regards, Ingo

chicks Members Profile Find Members Posts Debenu Quick PDF Library Expert Joined: 29 Oct 05 Location: United States Status: Offline Points: 251	Post Options Post Reply Quote chicks Report Post Thanks(0) Quote Reply Posted: 16 Aug 07 at 3:05PM
	Ingo, Have a look at pdfinfo here: pdfinfo It's a first attempt to parse a PDF's dictionary objects. It will display the encryption type for the files I've tested it on, but probably won't work for all. Please test.