ExiFREE

Small EXIF data eraser.

About

    Exchangeable Image File Format - EXIF, is a standard that specifies the formats for images,
sound and ancillary tags used by digital cameras and smartphones.
    ExiFree is not a Exif library - it is a standalone C code written
from scratch.

Purpose

To remove (erase) data stored in JPEG files that are part of the EXIF.
Here are some examples of data that can be stored in image files, depending
on the configuration of the camera/smartphone:
    - GPS location data;
    - device model and maker;
    - software details;
    - date and time at the moment the picture was taken and more.

Building

Update test submodule
    git submodule update --init --recursive .

Build the binary
    make

Build and run against the test images imported as git submodule from:
    https://github.com/ianare/exif-samples

    make test

An error-free run will look like:

    $ make test
    rm -f exifree
    rm -rf exif-samples/jpg/gps/wiped_DSCN0010.jpg-bin
    /usr/bin/find exif-samples/jpg/ -name "wiped_*" -exec rm -f {} \;
    /usr/bin/gcc exifree.c fs.c buffer.c hexdump.c -Wall -Werror -o /home/user/exifree/exifree
    cd  exif-samples/jpg && ls *.jpg| while read x ; do /home/user/exifree/exifree -d . -f $x >/dev/null && md5=$(/usr/bin/md5sum wiped_$x |cut -d " " -f1) && match=$(grep $x  /home/user/exifree/test-useres.txt| cut -d " " -f1); if [ $md5 != $match ]; then echo ;	echo "!!!!!!!!!!!!! Fail user test for  exif-samples/jpg/$x :~("; echo; fi; done
    cd  exif-samples/jpg/tests && ls *.jpg| while read x ; do /home/user/exifree/exifree -d . -f $x >/dev/null && md5=$(/usr/bin/md5sum wiped_$x |cut -d " " -f1) && match=$(grep $x  /home/user/exifree/test-useres.txt| cut -d " " -f1); if [ $md5 != $match ]; then echo ;	echo "!!!!!!!!!!!!! Fail user test for  exif-samples/jpg/tests/$x :~("; echo; fi; done
    cd  exif-samples/jpg/mobile && ls *.jpg| while read x ; do /home/user/exifree/exifree -d . -f $x >/dev/null && md5=$(/usr/bin/md5sum wiped_$x |cut -d " " -f1) && match=$(grep $x  /home/user/exifree/test-useres.txt| cut -d " " -f1); if [ $md5 != $match ]; then echo ;	echo "!!!!!!!!!!!!! Fail user test for  exif-samples/jpg/mobile/$x :~("; echo; fi; done
    cd  exif-samples/jpg/gps && ls *.jpg| while read x ; do /home/user/exifree/exifree -d . -f $x >/dev/null && md5=$(/usr/bin/md5sum wiped_$x |cut -d " " -f1) && match=$(grep $x  /home/user/exifree/test-useres.txt| cut -d " " -f1); if [ $md5 != $match ]; then echo ;	echo "!!!!!!!!!!!!! Fail user test for  exif-samples/jpg/gps/$x :~("; echo; fi; done
    cd  exif-samples/jpg/hdr && ls *.jpg| while read x ; do /home/user/exifree/exifree -d . -f $x >/dev/null && md5=$(/usr/bin/md5sum wiped_$x |cut -d " " -f1) && match=$(grep $x  /home/user/exifree/test-useres.txt| cut -d " " -f1); if [ $md5 != $match ]; then echo ;	echo "!!!!!!!!!!!!! Fail user test for  exif-samples/jpg/hdr/$x :~("; echo; fi; done
    cd  exif-samples/jpg/gps && /home/user/exifree/exifree -f DSCN0010.jpg -s -d . >/dev/null && cd - && hexdump -C  exif-samples/jpg/gps/wiped_DSCN0010.jpg-bin/* >  exif-samples/jpg/gps/wiped_DSCN0010.jpg-bin/wiped_diff.diff && diff /home/user/exifree/md5-01-sct.txt  exif-samples/jpg/gps/wiped_DSCN0010.jpg-bin/wiped_diff.diff ; if [ $? != 0 ]; then echo ;	echo "!!!!!!!!!!!!! Fail hex test for  exif-samples/jpg/gps/wiped_DSCN0010.jpg-bin files :~("; echo; fi;
    /home/user/exifree

Usage

$ ./exifree -h
Usage: exifree [OPTION]... <FILE>

Optional arguments
 -f <jpeg file>
 -d <dirname>   output directory
 -v             verbose dump sections
 -r             dry-run
 -s             save exif sections in dirname
 -h             show this help

Parameter	Description
<image file>	Wipe out exif contents & save the output as wiped_<image file>
-r	Dry-run against image file - sanity test without generating an output
-v	Verbose show sections details to standard output
-s	Save sections in output wiped_<image file>-bin
-d <destination directory>	Save output file (and sections if used) in destination directory
-h	Show help and exit

Sample output

Running with -v (long output, showing here begin-end only)

Running with -s

A glimpse of before and after

References

https://www.awaresystems.be/imaging/tiff/tifftags.html
http://exif.org

Bugs

Currently working on find & name them but surely
there are some or many.

Improvements needed

Support more image formats
Support more image tags
Implement fuzzer module