From 7697fa4daf3ec84f85711a84035d8f0224afd4e3 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?S=C3=A9bastien=20Delafond?= Date: Sun, 13 Jul 2014 13:35:01 +0200 Subject: Imported Upstream version 7.9.2 --- lisp/org-crypt.el | 273 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 273 insertions(+) create mode 100644 lisp/org-crypt.el (limited to 'lisp/org-crypt.el') diff --git a/lisp/org-crypt.el b/lisp/org-crypt.el new file mode 100644 index 0000000..a187d2f --- /dev/null +++ b/lisp/org-crypt.el @@ -0,0 +1,273 @@ +;;; org-crypt.el --- Public key encryption for org-mode entries + +;; Copyright (C) 2007, 2009-2012 Free Software Foundation, Inc. + +;; Emacs Lisp Archive Entry +;; Filename: org-crypt.el +;; Keywords: org-mode +;; Author: John Wiegley +;; Maintainer: Peter Jones +;; 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 . + +;;; 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. +;; If the key is not set, org-crypt will default to symmetric encryption. +;; +;; 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. + +;;; Thanks: + +;; - Carsten Dominik +;; - Vitaly Ostanin + +(require 'org) + +;;; Code: + +(declare-function epg-decrypt-string "epg" (context cipher)) +(declare-function epg-list-keys "epg" (context &optional name mode)) +(declare-function epg-make-context "epg" + (&optional protocol armor textmode include-certs + cipher-algorithm digest-algorithm + compress-algorithm)) +(declare-function epg-encrypt-string "epg" + (context plain recipients &optional sign always-trust)) + +(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 "" + "The default key to use when encrypting the contents of a heading. + +This setting can also be overridden in the CRYPTKEY property." + :type 'string + :group 'org-crypt) + +(defcustom org-crypt-disable-auto-save 'ask + "What org-decrypt should do if `auto-save-mode' is enabled. + +t : Disable auto-save-mode for the current buffer + prior to decrypting an entry. + +nil : Leave auto-save-mode enabled. + This may cause data to be written to disk unencrypted! + +'ask : Ask user whether or not to disable auto-save-mode + for the current buffer. + +'encrypt : Leave auto-save-mode enabled for the current buffer, + but automatically re-encrypt all decrypted entries + *before* auto-saving. + NOTE: This only works for entries which have a tag + that matches `org-crypt-tag-matcher'." + :group 'org-crypt + :version "24.1" + :type '(choice (const :tag "Always" t) + (const :tag "Never" nil) + (const :tag "Ask" ask) + (const :tag "Encrypt" encrypt))) + +(defun org-crypt-check-auto-save () + "Check whether auto-save-mode is enabled for the current buffer. + +`auto-save-mode' may cause leakage when decrypting entries, so +check whether it's enabled, and decide what to do about it. + +See `org-crypt-disable-auto-save'." + (when buffer-auto-save-file-name + (cond + ((or + (eq org-crypt-disable-auto-save t) + (and + (eq org-crypt-disable-auto-save 'ask) + (y-or-n-p "org-decrypt: auto-save-mode may cause leakage. Disable it for current buffer? "))) + (message (concat "org-decrypt: Disabling auto-save-mode for " (or (buffer-file-name) (current-buffer)))) + ; The argument to auto-save-mode has to be "-1", since + ; giving a "nil" argument toggles instead of disabling. + (auto-save-mode -1)) + ((eq org-crypt-disable-auto-save nil) + (message "org-decrypt: Decrypting entry with auto-save-mode enabled. This may cause leakage.")) + ((eq org-crypt-disable-auto-save 'encrypt) + (message "org-decrypt: Enabling re-encryption on auto-save.") + (add-hook 'auto-save-hook + (lambda () + (message "org-crypt: Re-encrypting all decrypted entries due to auto-save.") + (org-encrypt-entries)) + nil t)) + (t nil)))) + +(defun org-crypt-key-for-heading () + "Return 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) + (message "No crypt key set, using symmetric encryption.")))) + +(defun org-encrypt-string (str crypt-key) + "Return STR encrypted with CRYPT-KEY." + ;; Text and key have to be identical, otherwise we re-crypt. + (if (and (string= crypt-key (get-text-property 0 'org-crypt-key str)) + (string= (sha1 str) (get-text-property 0 'org-crypt-checksum str))) + (get-text-property 0 'org-crypt-text str) + (let ((epg-context (epg-make-context nil t t))) + (epg-encrypt-string epg-context str (epg-list-keys epg-context crypt-key))))) + +(defun org-encrypt-entry () + "Encrypt the content of the current headline." + (interactive) + (require 'epg) + (save-excursion + (org-back-to-heading t) + (let ((start-heading (point))) + (forward-line) + (when (not (looking-at "-----BEGIN PGP MESSAGE-----")) + (let ((folded (outline-invisible-p)) + (epg-context (epg-make-context nil t t)) + (crypt-key (org-crypt-key-for-heading)) + (beg (point)) + end encrypted-text) + (goto-char start-heading) + (org-end-of-subtree t t) + (org-back-over-empty-lines) + (setq end (point) + encrypted-text + (org-encrypt-string (buffer-substring beg end) crypt-key)) + (delete-region beg end) + (insert encrypted-text) + (when folded + (goto-char start-heading) + (hide-subtree)) + nil))))) + +(defun org-decrypt-entry () + "Decrypt the content of the current headline." + (interactive) + (require 'epg) + (unless (org-before-first-heading-p) + (save-excursion + (org-back-to-heading t) + (let ((heading-point (point)) + (heading-was-invisible-p + (save-excursion + (outline-end-of-heading) + (outline-invisible-p)))) + (forward-line) + (when (looking-at "-----BEGIN PGP MESSAGE-----") + (org-crypt-check-auto-save) + (let* ((end (save-excursion + (search-forward "-----END PGP MESSAGE-----") + (forward-line) + (point))) + (epg-context (epg-make-context nil t t)) + (encrypted-text (buffer-substring-no-properties (point) end)) + (decrypted-text + (decode-coding-string + (epg-decrypt-string + epg-context + encrypted-text) + 'utf-8))) + ;; Delete region starting just before point, because the + ;; outline property starts at the \n of the heading. + (delete-region (1- (point)) end) + ;; Store a checksum of the decrypted and the encrypted + ;; text value. This allow to reuse the same encrypted text + ;; if the text does not change, and therefore avoid a + ;; re-encryption process. + (insert "\n" (propertize decrypted-text + 'org-crypt-checksum (sha1 decrypted-text) + 'org-crypt-key (org-crypt-key-for-heading) + 'org-crypt-text encrypted-text)) + (when heading-was-invisible-p + (goto-char heading-point) + (org-flag-subtree t)) + nil)))))) + +(defun org-encrypt-entries () + "Encrypt all top-level entries in the current buffer." + (interactive) + (let (todo-only) + (org-scan-tags + 'org-encrypt-entry + (cdr (org-make-tags-matcher org-crypt-tag-matcher)) + todo-only))) + +(defun org-decrypt-entries () + "Decrypt all entries in the current buffer." + (interactive) + (let (todo-only) + (org-scan-tags + 'org-decrypt-entry + (cdr (org-make-tags-matcher org-crypt-tag-matcher)) + todo-only))) + +(defun org-at-encrypted-entry-p () + "Is the current entry encrypted?" + (unless (org-before-first-heading-p) + (save-excursion + (org-back-to-heading t) + (search-forward "-----BEGIN PGP MESSAGE-----" + (save-excursion (org-end-of-subtree t)) t)))) + +(defun org-crypt-use-before-save-magic () + "Add a hook to 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)))) + +(add-hook 'org-reveal-start-hook 'org-decrypt-entry) + +(provide 'org-crypt) + +;;; org-crypt.el ends here -- cgit v1.2.3