EasyPG is yet another GnuPG interface for Emacs. It consists of two parts:
-- "The EasyPG Assistant" which provides basic GUI of GnuPG
-- "The EasyPG Library" which enables use of various features of GnuPG
+- "The EasyPG Assistant"
+ A GUI frontend of GnuPG
+- "The EasyPG Library"
+ A library to interact with GnuPG
-NOTE: EasyPG is neither a fork nor a re-implementation of Gnus/PGG.
+NOTE: EasyPG is neither a fork nor a re-implementation of PGG.
* Requirements
(require 'epa-setup)
-Then you can browse your keyring by M-x epa-list-keys. In addition,
+Then you can browse your keyring by `M-x epa-list-keys'. In addition,
you can do some cryptographic operations on dired.
M-x dired
: e (or M-x epg-dired-do-encrypt)
(select recipients and click [OK])
-* Security consideration
+* Security
-** `call-process-region' writes data in region to a temporary file
+There are security pitfalls around Emacs.
+
+** Passphrase may leak to a temporary file.
`call-process-region' writes data in region to a temporary file.
-EasyPG does *not* use `call-process-region' to communicate with a gpg
+The EasyPG Library does not use `call-process-region' to communicate with a gpg
subprocess.
-** `(fillarray string 0)' is not enough to clear passphrases
+** Passphrase may be stolen from a core file.
If Emacs crashes and dumps core, Lisp strings in memory are also
dumped within the core file. `read-passwd' function clears passphrase
strings by `(fillarray string 0)'. However, Emacs performs compaction
in gc_sweep phase. If GC happens before `fillarray', passphrase
strings may be moved elsewhere in memory. Therefore, passphrase
-caching in Elisp is generally a bad idea. The EasyPG Library dares to
-disable passphrase caching.
-
-Fortunately, there is more secure way to cache passphrases - use
-gpg-agent.
+caching in elisp is generally a bad idea.
-Elisp programs can set `epg-context-passphrase-callback' to cache
-user's passphrases, it is not recommended though.
+The EasyPG Library dares to disable passphrase caching. Fortunately,
+there is more secure way to cache passphrases - use gpg-agent. Elisp
+programs can set `epg-context-passphrase-callback' to cache user's
+passphrases, it is not recommended though.