Install org-crypt.el by John Wiegley and Peter Jones

ChangeLog

@@ -1,3 +1,7 @@
+2009-09-16  Carsten Dominik  <carsten.dominik@gmail.com>
+
+	* Makefile: Add dependencies for org-crypt.el.
+
 2009-08-06  Carsten Dominik  <carsten.dominik@gmail.com>
 
 	* ORGWEBPAGE/index.org: Document that Emacs 23.1 ships with

Makefile

@@ -69,6 +69,7 @@ LISPF      = 	org.el			\
 	     	org-colview.el		\
 	     	org-colview-xemacs.el	\
 	     	org-compat.el		\
+	     	org-crypt.el		\
 		org-exp.el		\
 		org-exp-blocks.el	\
 		org-docbook.el		\
@@ -339,6 +340,7 @@ lisp/org-clock.elc:	lisp/org.el
 lisp/org-colview.elc:	lisp/org.el
 lisp/org-colview-xemacs.elc:	lisp/org.el
 lisp/org-compat.elc:	lisp/org-macs.el
+lisp/org-crypt.elc:	lisp/org-crypt.el lisp/org.el
 lisp/org-exp.elc:	lisp/org.el lisp/org-agenda.el
 lisp/org-exp-blocks.elc: lisp/org.el
 lisp/org-latex.elc:	lisp/org.el lisp/org-exp.el

lisp/ChangeLog

@@ -1,3 +1,9 @@
+2009-09-16  Carsten Dominik  <carsten.dominik@gmail.com>
+
+	* org-crypt.el: New file.
+
+	* org.el: Add an entry for org-crypt.
+
 2009-09-15  Carsten Dominik  <carsten.dominik@gmail.com>
 
 	* org-table.el (orgtbl-line-start-regexp): Match also TBLNAME

lisp/org-crypt.el

@@ -0,0 +1,168 @@
+;;; org-crypt.el --- Public key encryption for org-mode entries
+
+;; Copyright (C) 2009 Peter Jones <pjones@pmade.com>
+;; Copyright (C) 2007 John Wiegley <johnw@gnu.org>
+
+;; Emacs Lisp Archive Entry
+;; Filename: org-crypt.el
+;; Version: 0.4
+;; Keywords: org-mode
+;; Author: John Wiegley <johnw@gnu.org>
+;; Maintainer: Peter Jones <pjones@pmade.com>
+;; Description: Adds public key encryption to org-mode buffers
+;; URL: http://www.newartisans.com/software/emacs.html
+;; Compatibility: Emacs22
+
+;; This file is part of GNU Emacs.
+;;
+;; GNU Emacs is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; GNU Emacs is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; Right now this is just a set of functions to play with.  It depends
+;; on the epg library.  Here's how you would use it:
+;;
+;; 1. To mark an entry for encryption, tag the heading with "crypt".
+;;    You can change the tag to any complex tag matching string by
+;;    setting the `org-crypt-tag-matcher' variable.
+;;
+;; 2. Set the encryption key to use in the `org-crypt-key' variable,
+;;    or use `M-x org-set-property' to set the property CRYPTKEY to
+;;    any address in your public keyring.  The text of the entry (but
+;;    not its properties or headline) will be encrypted for this user.
+;;    For them to read it, the corresponding secret key must be
+;;    located in the secret key ring of the account where you try to
+;;    decrypt it.  This makes it possible to leave secure notes that
+;;    only the intended recipient can read in a shared-org-mode-files
+;;    scenario.
+;;
+;; 3. To later decrypt an entry, use `org-decrypt-entries' or
+;;    `org-decrypt-entry'.  It might be useful to bind this to a key,
+;;    like C-c C-/.  I hope that in the future, C-c C-r can be might
+;;    overloaded to also decrypt an entry if it's encrypted, since
+;;    that fits nicely with the meaning of "reveal".
+;;
+;; 4. To automatically encrypt all necessary entries when saving a
+;;    file, call `org-crypt-use-before-save-magic' after loading
+;;    org-crypt.el.
+;;
+;; TODO:
+;;   - Allow symmetric encryption as well
+
+;;; Thanks:
+
+;; - Carsten Dominik
+;; - Vitaly Ostanin
+
+(require 'org)
+(require 'epg)
+
+(defgroup org-crypt nil
+  "Org Crypt"
+  :tag "Org Crypt" :group 'org)
+
+(defcustom org-crypt-tag-matcher "crypt"
+  "The tag matcher used to find headings whose contents should be
+encrypted.  See the \"Match syntax\" section of the org manual
+for more details."
+  :type 'string :group 'org-crypt)
+
+(defcustom org-crypt-key nil
+  "The default key to use when encrypting the contents of a
+heading.  This can also be overridden in the CRYPTKEY property."
+  :type 'string :group 'org-crypt)
+
+(defun org-crypt-key-for-heading ()
+  "Returns the encryption key for the current heading."
+  (save-excursion
+    (org-back-to-heading t)
+    (or (org-entry-get nil "CRYPTKEY" 'selective) 
+        org-crypt-key
+        (and (boundp 'epa-file-encrypt-to) epa-file-encrypt-to)
+        (error "No crypt key set"))))
+
+(defun org-encrypt-entry ()
+  "Encrypt the content of the current headline."
+  (interactive)
+  (save-excursion
+    (org-back-to-heading t)
+    (forward-line)
+    (when (not (looking-at "-----BEGIN PGP MESSAGE-----"))
+      (let ((folded (org-invisible-p))
+	    (epg-context (epg-make-context nil t t))
+	    (crypt-key (org-crypt-key-for-heading))
+	    (beg (point))
+	    end encrypted-text)
+	(org-end-of-subtree t t)
+	(org-back-over-empty-lines)
+        (setq end (point)
+              encrypted-text
+              (epg-encrypt-string 
+               epg-context
+               (buffer-substring-no-properties beg end)
+               (epg-list-keys epg-context crypt-key)))
+        (delete-region beg end)
+        (insert encrypted-text)
+	(when folded
+	  (save-excursion
+	    (org-back-to-heading t)
+	    (hide-subtree)))
+        nil))))
+
+(defun org-decrypt-entry ()
+  (interactive)
+  (save-excursion
+    (org-back-to-heading t)
+    (forward-line)
+    (when (looking-at "-----BEGIN PGP MESSAGE-----")
+      (let* ((beg (point))
+             (end (save-excursion 
+                    (search-forward "-----END PGP MESSAGE-----")
+                    (forward-line)
+                    (point)))
+             (epg-context (epg-make-context nil t t))
+             (decrypted-text 
+	      (decode-coding-string
+	       (epg-decrypt-string
+		epg-context
+		(buffer-substring-no-properties beg end))
+	       'utf-8)))
+        (delete-region beg end)
+        (insert decrypted-text)
+        nil))))
+
+(defun org-encrypt-entries ()
+  (interactive)
+  (org-scan-tags
+   'org-encrypt-entry
+   (cdr (org-make-tags-matcher org-crypt-tag-matcher))))
+
+(defun org-decrypt-entries ()
+  (interactive)
+  (org-scan-tags 
+   'org-decrypt-entry
+   (cdr (org-make-tags-matcher org-crypt-tag-matcher))))
+
+(defun org-crypt-use-before-save-magic ()
+  "Adds a hook that will automatically encrypt entries before a
+file is saved to disk."
+  (add-hook 
+   'org-mode-hook 
+   (lambda () (add-hook 'before-save-hook 'org-encrypt-entries nil t))))
+  
+(provide 'org-crypt)
+
+;; arch-tag: 8202ed2c-221e-4001-9e4b-54674a7e846e
+
+;;; org-crypt.el ends here

lisp/org.el

@@ -183,6 +183,7 @@ to add the symbol `xyz', and the package must have a call to
   '(set :greedy t
 	(const :tag "   bbdb:              Links to BBDB entries" org-bbdb)
 	(const :tag "   bibtex:            Links to BibTeX entries" org-bibtex)
+	(const :tag "   crypt:             Encryption of subtrees" org-crypt)
 	(const :tag "   gnus:              Links to GNUS folders/messages" org-gnus)
 	(const :tag "   id:                Global IDs for identifying entries" org-id)
 	(const :tag "   info:              Links to Info nodes" org-info)