planet.donarmstrong.com

I started hacking on this a while back but I’ve finally done the house-keeping tasks required to make it a proper grown up package.

dired-rsync is a simple command which you can use to trigger an rsync copy from within dired. This is especially useful when you want to copy across large files from a remote server without locking up Emacs/Tramp. The rsync just runs as an inferior process in the background.

Today was mainly a process of cleaning up the CI and fixing any issues with it. I’d still like to add some proper tests but the whole thing is interactive and that seems to be tricky for Emacs to test. Anyway I’ve now tagged 0.4 so it will be available from MELPA Stable once it rebuilds. You can of course grab the building edge from MELPA any time

In the past Emacs was communicating w/ gnupg directly & hence was responsible for reading/sending/catching passwords. In contrast, Emacs 26.1, by default, fully delegates the password handling to gpg2.

The code for the interoperation w/ gpg1 is still present in the Emacs core, but it's no longer advertised in favour of gpg2 + elpa pinentry.

If you don't want an additional overhead or a special gpg-agent setup, it's still possible to use gpg1 for (en|de)crypting ops.

Say we have a text file we want to encrypt & then transparently edit in Emacs afterwards. The editor should remember the correct pw for the file & not bother us w/ the pw during the file saving op.

$ rpm -qf `which gpg gpg2`
gnupg-1.4.22-6.fc28.x86_64
gnupg2-2.2.6-1.fc28.x86_64

$ echo rain raine goe away, little Johnny wants to play | gpg -c > nr.gpg
$ file nr.gpg
nr.gpg: GPG symmetrically encrypted data (AES cipher)

If you have both gpg1 & gpg2 installed, Emacs ignores gpg1 completely. E.g., run 'emacs -Q' & open nr.gpg file–gpg2 promptly contacts gpg-agent, which, in turn, runs the pinentry app:

Although, it may look as if everything is alright, try to edit the decrypted file & then save it. The pinentry window will reappear & you'll be forced to enter the pw twice.

The Emacs mode that handles the gnupg dispatch is called EasyPG Assistant. To check its current state, use epg-find-configuration fn:

ELISP> (car (epg-find-configuration 'OpenPGP))
(program . "/usr/bin/gpg2")

We can force EasyPG to use gpg1, despite that it's not documented anywhere.

The actual config data is located in epg-config--program-alist var:

ELISP> epg-config--program-alist
((OpenPGP epg-gpg-program
      ("gpg2" . "2.1.6")
      ("gpg" . "1.4.3"))
 (CMS epg-gpgsm-program
      ("gpgsm" . "2.0.4")))

Here, if we shadow the gpg2 entry in the alist, EasyPG would regenerate a new config for all the (en|de)crypting ops on the fly:

(require 'epg-config)
(add-to-list 'epg-config--program-alist `(OpenPGP epg-gpg-program ("gpg" . ,epg-gpg-minimum-version)))
(setq epa-file-cache-passphrase-for-symmetric-encryption t)
(setq epg--configurations nil)

Now, if you open nr.gpg afresh, Emacs neither should use the gpg-agent any more:

Nor should it ask for the pw when you'll do edit+save later on.

To clear the internal pw cache, type

ELISP> (setq epa-file-passphrase-alist nil)