X-Git-Url: http://git.chise.org/gitweb/?a=blobdiff_plain;f=README;h=e231330cd6b256fdddcf68adf805ad03bd5bc6c7;hb=95ff40c9179c88308fe96e1adb0ef220b67f265c;hp=036744893557fa7e6c7c87e504f3a3977e567672;hpb=08eb93f7db855053a3366e562657ff6c9a80bd58;p=elisp%2Fepg.git diff --git a/README b/README index 0367448..e231330 100644 --- a/README +++ b/README @@ -16,11 +16,16 @@ elisp library to interact with GnuPG. * Quick start +** Installation + +$ ./configure +$ sudo make install + ** Transparent file encryption utility EasyPG provides transparent file encryption utility similar to -crypt++, alpaca.el, hedgehog. To try this feature, add the following -line to your ~/.emacs and C-x C-f ~/test.txt.gpg. +crypt++, alpaca.el, hedgehog. To try this, add the following line to +your ~/.emacs and C-x C-f ~/test.txt.gpg. (require 'epg-file) @@ -34,27 +39,28 @@ add the following line to your ~/.gnus. * Advantages over other competitors -There are many competitors of EasyPG such as Mailcrypt, PGG, gpg.el, -etc. EasyPG has some advantages over them. +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. +** 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 -`call-process-region' writes data in region to temporary files. PGG -and gpg.el use `call-process-region' to communicate with a gpg -subprocess. Your passphrases leak to the filesystem! +`call-process-region' writes data in region to temporary files. +EasyPG do _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 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. It is recommended that as -soon as you are done with passphrase you should clear it manually. -However, PGG and gpg.el can keep passphrase strings in cache for a -while and this behavior is their default! +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