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From Stefan Bodewig <>
Subject Re: [compress] Support for strong encryption in zip files?
Date Wed, 12 Jun 2013 07:23:30 GMT
On 2013-06-12, Bear Giles wrote:

> What is the status on strong encryption in zip files? That is - I know we
> don't have it, but is there a reason why it hasn't been added or is it just
> an itch that hasn't been scratched?

> I can see several levels of values

> 1. add ZipExtraField handlers for the five extra fields of interest (0x14,
> 0x15, 0x16, 0x17, 0x19) even if encryption/decryption isn't supported. It
> could still provide useful information, e.g., identifying users able to
> decrypt the file.
> 2. add read-only support.
> 3. add write support.

> The two potential issues I've found so far are 1) export/import
> restrictions that may limit functionality and 2) language in the PKWARE
> documentation at

export/import restrictions are no big problem since we'd basically rely
on JCE anyway - we might need to add Compress to
<> but nothing more.

For me the note from APPNOTE.TXT is the major problem, but then again
we've never consulted with our legal folks or reached out to PKWARE to
see what is and what is not possible.

The first item of your list - adding extra fields - should still be

> A related question involves support for the legacy encryption. It's
> easily cracked but people might need to read old encrypted files. It's
> even possible that some people may still be forced to use it because
> of contractual obligations.

Read-only support would probably be nice, write support is something I
personally wouldn't be interested in - as it provides some false idea of

TBH two years (or more?) ago I flagged all JIRA tickets related to
alternative compressions methods and encryption as 2.x as I expected us
to come up with a proper API for this first - obviously nobody has found
the time or need to work on the 2.x API so far.


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