[gdal-dev] using encrypted data

[Frank Warmerdam]

Yilmaz Arslanoglu wrote:
> Hi all;
> 
> One of our customer wants to share their data which is in ESRI Shapefile format.
> However, they also would like to limit the usage of this data such
> that the contents
> will be utilized only through our software, and not for any other purposes.
> 
> Does anybody have a suggestion about how this could be achieved ?
> Does GDAL have any related encryption based support, and is there any
> GDAL supported encrypted vector formats that we can convert it into?

Yilmaz,

There are no encrypted GDAL or OGR formats that come to mind.

My suggestion is that you encrypt the shapefile(s) using some
generic encryption and then implement a VSI*L filesystem handler
for /vsiyilmazencrypt/ that would decrypt the data on the fly as
it is read.

The VSI*L file access layer provides for library and application
supplied custom file io handlers.  There are several examples of
implementations in gdal/port including cpl_vsil_subfile.cpp and
cpl_vsil_mem.cpp and cpl_vsil_unix_stdio_64.cpp.

I'm sure a good search on encryption libraries will turn up various
options for encryption libraries.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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