dakra / sodium.el

Emacs bindings for libsodium

Emacs bindings for libsodium

This module is in alpha, works only in Linux with Emacs 25+ and only exposes a high level interface to the crypto_box API.

Install

Run make and ensure that sodium.el is somewhere in your load path. Then

(require 'sodium)

If you use Borg, make sure to execute make in you .gitmodules build-step like this

[submodule "sodium"]
	path = lib/sodium
	url = [email protected]:dakra/sodium.el.git
	build-step = make

Usage

You can see sodium-box-demo.el for a simple example: (Run the box-demo with make box-demo)

(require 'sodium)

(let* ((nonce  (sodium-box-make-nonce))
       (bob    (sodium-box-keypair))
       (bob-pk (cdr (assoc 'pk bob)))
       (bob-sk (cdr (assoc 'sk bob)))
       (alice    (sodium-box-keypair))
       (alice-pk (cdr (assoc 'pk alice)))
       (alice-sk (cdr (assoc 'sk alice)))
       (msg "Hello World!")
       encrypted decrypted)
  (message "Encrypting message '%s'" msg)
  (setq encrypted (sodium-box msg nonce bob-pk alice-sk))
  (message "Decrypt message '%s'" encrypted)
  (setq decrypted (sodium-box-open encrypted nonce alice-pk bob-sk))
  (message "Decrypted message '%s'" decrypted))

Thanks

@jedisct1 for libsodium

Emacs module code was taken from/inspired by:

• https://phst.eu/emacs-modules
• https://github.com/skeeto/joymacs
• Looking at module code from https://github.com/syohex
• Emacs libgit2 bindings https://github.com/magit/libegit2
• http://diobla.info/blog-archive/modules-tut.html
• https://github.com/jkitchin/emacs-modules

sodium.el's Issues

Some early feedback

Hi,

And thanks for writing this module.

I quickly looked at the code, and there are quite a few things that might be improved:

• You should call sodium_init() before doing anything else.
• Hex conversion: no need to reimplement this. Base64 is also available, btw.
• Getting random data: already there as well, and using these functions will ensure that it works consistently across operating systems.
• Encryption: use crypto_box_keypair() to create a key pair, and crypto_box_easy()/crypto_box_open_easy(), or sealed boxes.
• What is the use case for this module? If you need to encrypt content for yourself, symmetric encryption is all you need. See Authenticated encryption.
• In order to store secrets, see secure memory functions provided by the library.

Also, libhydrogen may be better suited for your use cases.

Cheers,

-Frank.

Problems building: undefined_symbol: sodium_init

I was looking for emacs keepassxc integration and came across this and keepassxc.el, but am having trouble building.

First, I let straight fetch this for me via:

(use-package sodium
  :straight (:host github :repo "dakra/sodium.el"
                   :branch "master"))

which failed with:

Debugger entered--Lisp error: (file-missing "Cannot open load file" "No such file or directory" "libsodium")
  require(libsodium)

So then in a terminal I hopped into the repo directory and:

$ make
emacs -Q -batch -L . -f batch-byte-compile sodium.el
emacs: symbol lookup error: /home/len/.emacs.d/straight/repos/sodium.el/libsodium.so: undefined symbol: sodium_init
Makefile:19: recipe for target 'sodium.elc' failed
make: *** [sodium.elc] Error 127

Other info:

$  lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 18.04.3 LTS
Release:        18.04
Codename:       bionic
$ emacs --version
GNU Emacs 26.3
[...]
$ dpkg -l libsodium-dev
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name                                        Version                    Architecture               Description
+++-===========================================-==========================-==========================-============================================================================================
ii  libsodium-dev:amd64                         1.0.16-2                   amd64                      Network communication, cryptography and signaturing library - headers

Any ideas?