
Signify: Cryptographically Sign and Verify Files

HowTo: Use Signify on Debian (based) Distributions
Introduction[edit]
Written in 2014 for OpenBSD, signify is a tool to cryptographically sign and verify files: [1]
It only supports a single algorithm, Ed25519, created by djb and his gang. It’s fast, immune to timing attacks by design, produce deterministic signatures, uses small keys and produce small signatures, … it does look like a sound choice.
Signify's main benefits is that it has a small codebase and is not based on GnuPG. On the downside, there is no revocation mechanism [2] and the trust path relies on getting the key directly from a trusted developer. [1]
Signify's usage is not just limited to OpenBSD and the tool has also been been packaged in Debian. [3] To learn more about signify, refer to this blog post by the original author.
Installation and Usage[edit]
1. Install signify.
Install package(s) signify-openbsd qrencode
following these instructions
1 Platform specific notice.
- Kicksecure: No special notice.
- Kicksecure-Qubes: In Template.
2 Update the package lists and upgrade the system.
Click = Copy Copied to clipboard!
3 Install the signify-openbsd qrencode
package(s).
Using apt
command line --no-install-recommends
option is in most cases optional.
Click = Copy Copied to clipboard!
4 Platform specific notice.
- Kicksecure: No special notice.
- Kicksecure-Qubes: Shut down Template and restart App Qubes based on it as per Qubes Template Modification
.
5 Done.
The procedure of installing package(s) signify-openbsd qrencode
is complete.
2. Create a key.
This only needs to be done once unless multiple keys are desired; in that case different key names should be used. In the following example, keyname
is used as the sample key name.
Click = Copy Copied to clipboard!
3. Optional: Add a key comment.
Replace comments here
with the actual comment but keep the "
. The comment could be a name, position, website, e-mail address and/or anything else.
Click = Copy Copied to clipboard!
Note:
- The private key file
keyname.sec
needs to stay private -- never sharekeyname.sec
with anyone as this would defeat the purpose of signing files! - The public key file
keyname.pub
can be shared with anyone.
4. Utilize signify.
To sign a file message.txt
(which has to be created by the user beforehand).
Click = Copy Copied to clipboard!
This will create a signature file message.txt.sig
.
To verify a file message.txt
with signature file message.txt.sig
.
Click = Copy Copied to clipboard!
5. Optional: Create a QR code for the public key.
Click = Copy Copied to clipboard!
File keyname.pub.png
would be the QR code of the public key.
Refer to the Debian signify-openbsd Manual Page for further options.
See Also[edit]
Footnotes[edit]
- ↑ Jump up to: 1.0 1.1 https://isopenbsdsecu.re/mitigations/signify/
- ↑ Meaning if the key is stolen, people can only be informed the key should not be trusted anymore.
- ↑ https://packages.debian.org/bookworm/signify-openbsd
- ↑

We believe security software like Kicksecure needs to remain Open Source and independent. Would you help sustain and grow the project? Learn more about our 12 year success story and maybe DONATE!