* What's this?

EasyPG is yet another GnuPG interface for Emacs.  It consists of two parts:

- "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 PGG.

* Requirements

** GNU Emacs 21.4 or XEmacs 21.4

** GnuPG 1.4.3

* Quick start

** Installation

  $ ./configure
  $ sudo make install

Add the following line to your ~/.emacs

  (require 'epa-setup)

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
  (mark some files)
  : e (or M-x epg-dired-do-encrypt)
  (select recipients and click [OK])

* Security

There are security pitfalls around Emacs.

** Passphrase may leak to a temporary file.

`call-process-region' writes data in region to a temporary file.
The EasyPG Library does not use `call-process-region' to communicate with a gpg
subprocess.

** 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.  Elisp
programs can set `epg-context-passphrase-callback' to cache user's
passphrases, it is not recommended though.