stegage is a command line tool and Go library to both encrypt (with age) and conceal (with steganography) a file.
| Original image | Encoded image with the encrypted file inside |
|---|---|
 |
 |
stegage encrypts a file (f.ex. doc.txt) with a passphrase and embeds the
encrypted file inside an image (f.ex. stegage.jpeg. The resulting image stegage_encoded.png is
visually identical to the original image stegage.jpeg.
┌────────────┐ ┌────────────┐
│ doc.txt │ encrypt │ doc.txt.enc│
│ ├─────────────►│ ├────┐
│ │ │ │ │ ┌─────────────────────────────────┐
│ │ │ │ │ │ stegage_encoded.png│
└────────────┘ └────────────┘ │ stegano │ │
│ graphy │ │
┌─────────────────────────────────┐ ├─────────►│ ┌────────────┐ │
│ stegage.jpeg │ │ │ │ doc.txt.enc│ │
│ │ │ │ │ │ │
│ │ │ │ │ │ │
│ │ │ │ │ │ │
│ │ │ │ └────────────┘ │
│ ├─┘ │ │
│ │ └─────────────────────────────────┘
│ │
│ │
│ │
└─────────────────────────────────┘
The supported image formats for embedding are jpeg and png. The resulting image format is always png.
stegage extracts the encrypted file from the embedding image and decrypts it.
┌─────────────────────────────────┐
│ stegage_encoded.png│
│ │ ┌────────────┐ ┌────────────┐
│ │ │ doc.txt.enc│ │ doc.txt │
│ ┌────────────┐ │ steganography │ │ decrypt │ │
│ │ doc.txt.enc│ ├────────────────►│ ├───────────►│ │
│ │ │ │ │ │ │ │
│ │ │ │ └────────────┘ └────────────┘
│ │ │ │
│ └────────────┘ │
│ │
└─────────────────────────────────┘
Encrypt the file doc.txt and embed the encrypted payload in a copy of
stegage.png. Save the copy to the file stegage_encoded.png.
⤷ stegage encode --inside stegage.png doc.txt > stegage_encoded.png
Enter passphrase:
Confirm passphrase:Extract the encrypted payload from the file stegage_encoded.png and decrypt
it. Save the decrypted payload to the file doc.txt
⤷ stegage decode stegage_encoded.png > doc.txt
Enter passphrase:You can download the latest release versions of stegage from the stegage release page.
If your system has Go 1.17+:
go install github.com/revelaction/stegage/cmd...@v0.7.1-beta// error handling omitted for brevity. See ./cmd/stegage/main.go for a real example
image, _ := os.Open(image.png)
passphrase:= strings.NewReader("aj4@7%8821vja")
data, _ := os.Open("doc.txt")
out, _ := os.Create("encoded.png")
err := stegage.Encode(passphrase, data, image, out); err != nil {
fmt.Printf("stegage: error encoding: %v", err)
}imageEncoded, _ := os.Open(image_encoded.png)
passphrase := strings.NewReader("aj4@7%8821vja")
out, _ := os.Create("doc.txt")
err := stegage.Decode(passphrase, imageEncoded, out); err != nil {
fmt.Printf("stegage: error decoding: %v", err)
}stegage has builtin bash autocompletion. You can enable it by putting the following bash
snippet in your .bashrc file:
if hash stegage; then
PROG=stegage source <(stegage bash)
fi⤷ stegage help
NAME:
stegage - encrypt and conceal (steganography) a file
USAGE:
stegage [global options] command [command options] [arguments...]
COMMANDS:
encode, e Encrypt a file with age and additionally conceal with steganography
decode, d Decrypt an age encrypted file inside of an image file
bash Dump bash complete script
help, h Shows a list of commands or help for one command
GLOBAL OPTIONS:
--help, -h show help (default: false)