stegify
is a simple command line tool capable of fully transparent hiding any file within an image or set of images.
This technique is known as LSB (Least Significant Bit) steganography
Carrier | Data | Result |
---|---|---|
The Result
file contains the Data
file hidden in it. And as you can see it is fully transparent.
If multiple Carrier
files are provided, the Data
file will be split in pieces and every piece is encoded in the respective carrier.
Carrier1 | Carrier2 | Data | Result1 | Result2 |
---|---|---|---|---|
The Result1
file contains one half of the Data
file hidden in it and Result2
the other. As always fully transparent.
go install github.com/DimitarPetrov/stegify@latest
brew tap DimitarPetrov/stegify
brew install stegify
Or you can download a binary for your system here.
stegify encode --carrier <file-name> --data <file-name> --result <file-name>
stegify decode --carrier <file-name> --result <file-name>
When encoding, the file with name given to flag --data
is hidden inside the file with name given to flag
--carrier
and the resulting file is saved in new file in the current working directory under the
name given to flag --result
.
NOTE: The result file won't have any file extension and therefore it should be specified explicitly in
--result
flag.
When decoding, given a file name of a carrier file with previously encoded data in it, the data is extracted
and saved in new file in the current working directory under the name given to flag --result
.
NOTE: The result file won't have any file extension and therefore it should be specified explicitly in
--result
flag.
In both cases the flag --result
could be omitted and default values will be used.
stegify encode --carriers "<file-names...>" --data <file-name> --results "<file-names...>"
OR
stegify encode --carrier <file-name> --carrier <file-name> ... --data <file-name> --result <file-name> --result <file-name> ...
stegify decode --carriers "<file-names...>" --result <file-name>
OR
stegify decode --carrier <file-name> --carrier <file-name> ... --result <file-name>
When encoding a data file in more than one carriers, the data file is split in N chunks, where N is number of provided carriers. Each of the chunks is then encoded in the respective carrier.
NOTE: When decoding, carriers should be provided in the exact same order for result to be properly extracted.
This kind of encoding provides one more layer of security and more flexibility regarding size limitations.
In both cases the flag --result/--results
could be omitted and default values will be used.
NOTE: When encoding the number of the result files (if provided) should be equal to the number of carrier files. When decoding, exactly one result is expected.
When multiple carriers are provided with mixed kinds of flags, the names provided through carrier
flag are taken first and with carriers/c
flags second.
Same goes for the result/results
flag.
stegify
can be used programmatically too and it provides easy to use functions working with file names
or raw Readers and Writers. You can visit godoc under
steg
package for details.
If carrier file is in jpeg or jpg format, after encoding the result file image will be png encoded (therefore it may be bigger in size) despite of file extension specified in the result flag.
stegify
was used for one of the Capture The Flag challenges in Codefestโ19.
Participants were given a photo of a bunch of "innocent" cats. Nothing suspicious right? Think again!