X-Git-Url: http://git.chise.org/gitweb/?a=blobdiff_plain;f=README;h=81a94abea80d0851b38e0fabbb30586e43f8ca74;hb=f7a28f60f11e7a71c5bfa97f3e420c86ca492a65;hp=bcf3731dcbb5faa2786e629e49e6a7fc669b2303;hpb=cd7a5af0110cb4e59e6d08fb8468c14610ff7cd1;p=elisp%2Fepg.git diff --git a/README b/README index bcf3731..81a94ab 100644 --- a/README +++ b/README @@ -1,56 +1,45 @@ * What's this? -EasyPG is yet another GnuPG interface for Emacs. It consists of three -parts: transparent file encryption utility, Gnus/PGG backend, and -elisp library to interact with GnuPG. +EasyPG is yet another GnuPG interface for Emacs. It consists of two parts: -* Requirements +- "The EasyPG Assistant" which provides basic GUI of GnuPG +- "The EasyPG Library" which enables use of various features of GnuPG -** GNU Emacs 21.4 or later +NOTE: EasyPG is not a fork or a re-implementation of Gnus/PGG. -** XEmacs 21.4 or later +* Requirements -** GnuPG 1.4.3 or later +** GNU Emacs 21.4 or later, XEmacs 21.4 or later -** Gnus 5.10.8 or later (optional) +** GnuPG 1.4.3 or later * Quick start ** Installation -$ ./configure -$ sudo make install - -** Transparent file encryption utility + $ ./configure + $ sudo make install -EasyPG provides transparent file encryption utility similar to -crypt++, alpaca.el, hedgehog. To try this, add the following line to -your ~/.emacs and C-x C-f ~/test.txt.gpg. +Add the following line to your ~/.emacs -(require 'epg-file) + (require 'epa-setup) -** Gnus/PGG backend +Then you can do some cryptographic operations on dired. -EasyPG provides an implementation of the backend interface of -Gnus/PGG. To use EasyPG instead of pgg-gpg, install pgg-epg.el and -add the following line to your ~/.gnus. + M-x dired + (mark some files) + : e (or M-x epg-dired-do-encrypt) + (select recipients and click [OK]) -(setq pgg-scheme 'epg) +* Security consideration -* Advantages over other competitors +** `call-process-region' writes data in region to a temporary file -There are many competitors of EasyPG such as Mailcrypt, Gnus/PGG, -gpg.el, etc. EasyPG has some advantages over them. - -** EasyPG avoides potential security flaws of Emacs. - -*** `call-process-region' writes data in region to temporary files. - -`call-process-region' writes data in region to temporary files. -EasyPG do _not_ use `call-process-region' to communicate with a gpg +`call-process-region' writes data in region to a temporary file. +EasyPG does *not* use `call-process-region' to communicate with a gpg subprocess. -*** There is no way to clear strings safely. +** `(fillarray string 0)' is not enough to clear passphrases If Emacs crashed and dumps core, passphrase strings in memory are also dumped within the core file. `read-passwd' function clears passphrase @@ -59,13 +48,6 @@ in gc_sweep phase. If GC happens before `fillarray', passphrase strings may be moved elsewhere in memory. Fortunately, there is gpg-agent to cache passphrases in more secure -way, so EasyPG dares _not_ to cache passphrase. Elisp programs can -set `epg-context-passphrase-callback' to cache user's passphrases. - -** GnuPG features are directly accessible from Emacs - -Other competitors provide only specific features of GnuPG since they -still support PGP 2.*, 5.*, 6.*. As the name indicates, EasyPG is -inspired by GPGME (GnuPG Made Easy), and the library interface is -close to GPGME. With EasyPG you can benefit from a lot of features of -GnuPG. +way, so the EasyPG library dares *not* to cache passphrase by itself. +Elisp programs can set `epg-context-passphrase-callback' to cache +user's passphrases.