mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-11-27 07:37:33 +00:00
261 lines
8.6 KiB
EmacsLisp
261 lines
8.6 KiB
EmacsLisp
;;; epa-file.el --- the EasyPG Assistant, transparent file encryption
|
|
;; Copyright (C) 2006, 2007, 2008 Free Software Foundation, Inc.
|
|
|
|
;; Author: Daiki Ueno <ueno@unixuser.org>
|
|
;; Keywords: PGP, GnuPG
|
|
|
|
;; 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/>.
|
|
|
|
;;; Code:
|
|
|
|
(require 'epa)
|
|
(require 'epa-hook)
|
|
|
|
(defcustom epa-file-cache-passphrase-for-symmetric-encryption nil
|
|
"If non-nil, cache passphrase for symmetric encryption."
|
|
:type 'boolean
|
|
:group 'epa-file)
|
|
|
|
(defcustom epa-file-select-keys nil
|
|
"If non-nil, always asks user to select recipients."
|
|
:type 'boolean
|
|
:group 'epa-file)
|
|
|
|
(defvar epa-file-passphrase-alist nil)
|
|
|
|
(eval-and-compile
|
|
(if (fboundp 'encode-coding-string)
|
|
(defalias 'epa-file--encode-coding-string 'encode-coding-string)
|
|
(defalias 'epa-file--encode-coding-string 'identity)))
|
|
|
|
(eval-and-compile
|
|
(if (fboundp 'decode-coding-string)
|
|
(defalias 'epa-file--decode-coding-string 'decode-coding-string)
|
|
(defalias 'epa-file--decode-coding-string 'identity)))
|
|
|
|
(defun epa-file-passphrase-callback-function (context key-id file)
|
|
(if (and epa-file-cache-passphrase-for-symmetric-encryption
|
|
(eq key-id 'SYM))
|
|
(progn
|
|
(setq file (file-truename file))
|
|
(let ((entry (assoc file epa-file-passphrase-alist))
|
|
passphrase)
|
|
(or (copy-sequence (cdr entry))
|
|
(progn
|
|
(unless entry
|
|
(setq entry (list file)
|
|
epa-file-passphrase-alist
|
|
(cons entry
|
|
epa-file-passphrase-alist)))
|
|
(setq passphrase (epa-passphrase-callback-function context
|
|
key-id nil))
|
|
(setcdr entry (copy-sequence passphrase))
|
|
passphrase))))
|
|
(epa-passphrase-callback-function context key-id nil)))
|
|
|
|
;;;###autoload
|
|
(defun epa-file-handler (operation &rest args)
|
|
(save-match-data
|
|
(let ((op (get operation 'epa-file)))
|
|
(if op
|
|
(apply op args)
|
|
(epa-file-run-real-handler operation args)))))
|
|
|
|
(defun epa-file-run-real-handler (operation args)
|
|
(let ((inhibit-file-name-handlers
|
|
(cons 'epa-file-handler
|
|
(and (eq inhibit-file-name-operation operation)
|
|
inhibit-file-name-handlers)))
|
|
(inhibit-file-name-operation operation))
|
|
(apply operation args)))
|
|
|
|
(defun epa-file-decode-and-insert (string file visit beg end replace)
|
|
(if (fboundp 'decode-coding-inserted-region)
|
|
(save-restriction
|
|
(narrow-to-region (point) (point))
|
|
(let ((multibyte enable-multibyte-characters))
|
|
(set-buffer-multibyte nil)
|
|
(insert string)
|
|
(set-buffer-multibyte multibyte)
|
|
(decode-coding-inserted-region
|
|
(point-min) (point-max)
|
|
(substring file 0 (string-match epa-file-name-regexp file))
|
|
visit beg end replace)))
|
|
(insert (epa-file--decode-coding-string string (or coding-system-for-read
|
|
'undecided)))))
|
|
|
|
(defvar last-coding-system-used)
|
|
(defun epa-file-insert-file-contents (file &optional visit beg end replace)
|
|
(barf-if-buffer-read-only)
|
|
(if (and visit (or beg end))
|
|
(error "Attempt to visit less than an entire file"))
|
|
(setq file (expand-file-name file))
|
|
(let* ((local-copy
|
|
(condition-case inl
|
|
(epa-file-run-real-handler #'file-local-copy (list file))
|
|
(error)))
|
|
(local-file (or local-copy file))
|
|
(context (epg-make-context))
|
|
string length entry)
|
|
(if visit
|
|
(setq buffer-file-name file))
|
|
(epg-context-set-passphrase-callback
|
|
context
|
|
(cons #'epa-file-passphrase-callback-function
|
|
local-file))
|
|
(epg-context-set-progress-callback context
|
|
#'epa-progress-callback-function)
|
|
(unwind-protect
|
|
(progn
|
|
(if replace
|
|
(goto-char (point-min)))
|
|
(condition-case error
|
|
(setq string (epg-decrypt-file context local-file nil))
|
|
(error
|
|
(if (setq entry (assoc file epa-file-passphrase-alist))
|
|
(setcdr entry nil))
|
|
(signal 'file-error
|
|
(cons "Opening input file" (cdr error)))))
|
|
(make-local-variable 'epa-file-encrypt-to)
|
|
(setq epa-file-encrypt-to
|
|
(mapcar #'car (epg-context-result-for context 'encrypted-to)))
|
|
(if (or beg end)
|
|
(setq string (substring string (or beg 0) end)))
|
|
(save-excursion
|
|
(save-restriction
|
|
(narrow-to-region (point) (point))
|
|
(epa-file-decode-and-insert string file visit beg end replace)
|
|
(setq length (- (point-max) (point-min))))
|
|
(if replace
|
|
(delete-region (point) (point-max)))))
|
|
(if (and local-copy
|
|
(file-exists-p local-copy))
|
|
(delete-file local-copy)))
|
|
(list file length)))
|
|
(put 'insert-file-contents 'epa-file 'epa-file-insert-file-contents)
|
|
|
|
(defun epa-file-write-region (start end file &optional append visit lockname
|
|
mustbenew)
|
|
(if append
|
|
(error "Can't append to the file."))
|
|
(setq file (expand-file-name file))
|
|
(let* ((coding-system (or coding-system-for-write
|
|
(if (fboundp 'select-safe-coding-system)
|
|
;; This is needed since Emacs 22 has
|
|
;; no-conversion setting for *.gpg in
|
|
;; `auto-coding-alist'.
|
|
(let ((buffer-file-name
|
|
(file-name-sans-extension file)))
|
|
(select-safe-coding-system
|
|
(point-min) (point-max)))
|
|
buffer-file-coding-system)))
|
|
(context (epg-make-context))
|
|
(coding-system-for-write 'binary)
|
|
string entry
|
|
(recipients
|
|
(cond
|
|
((listp epa-file-encrypt-to) epa-file-encrypt-to)
|
|
((stringp epa-file-encrypt-to) (list epa-file-encrypt-to)))))
|
|
(epg-context-set-passphrase-callback
|
|
context
|
|
(cons #'epa-file-passphrase-callback-function
|
|
file))
|
|
(epg-context-set-progress-callback context
|
|
#'epa-progress-callback-function)
|
|
(epg-context-set-armor context epa-armor)
|
|
(condition-case error
|
|
(setq string
|
|
(epg-encrypt-string
|
|
context
|
|
(if (stringp start)
|
|
(epa-file--encode-coding-string start coding-system)
|
|
(epa-file--encode-coding-string (buffer-substring start end)
|
|
coding-system))
|
|
(if (or epa-file-select-keys
|
|
(not (local-variable-p 'epa-file-encrypt-to
|
|
(current-buffer))))
|
|
(epa-select-keys
|
|
context
|
|
"Select recipents for encryption.
|
|
If no one is selected, symmetric encryption will be performed. "
|
|
recipients)
|
|
(if epa-file-encrypt-to
|
|
(epg-list-keys context recipients)))))
|
|
(error
|
|
(if (setq entry (assoc file epa-file-passphrase-alist))
|
|
(setcdr entry nil))
|
|
(signal 'file-error (cons "Opening output file" (cdr error)))))
|
|
(epa-file-run-real-handler
|
|
#'write-region
|
|
(list string nil file append visit lockname mustbenew))
|
|
(if (boundp 'last-coding-system-used)
|
|
(setq last-coding-system-used coding-system))
|
|
(if (eq visit t)
|
|
(progn
|
|
(setq buffer-file-name file)
|
|
(set-visited-file-modtime))
|
|
(if (stringp visit)
|
|
(progn
|
|
(set-visited-file-modtime)
|
|
(setq buffer-file-name visit))))
|
|
(if (or (eq visit t)
|
|
(eq visit nil)
|
|
(stringp visit))
|
|
(message "Wrote %s" buffer-file-name))))
|
|
(put 'write-region 'epa-file 'epa-file-write-region)
|
|
|
|
(defun epa-file-select-keys ()
|
|
"Select recipients for encryption."
|
|
(interactive)
|
|
(make-local-variable 'epa-file-encrypt-to)
|
|
(setq epa-file-encrypt-to
|
|
(mapcar
|
|
(lambda (key)
|
|
(epg-sub-key-id (car (epg-key-sub-key-list key))))
|
|
(epa-select-keys
|
|
(epg-make-context)
|
|
"Select recipents for encryption.
|
|
If no one is selected, symmetric encryption will be performed. "))))
|
|
|
|
;;;###autoload
|
|
(defun epa-file-enable ()
|
|
(interactive)
|
|
(if (memq epa-file-handler file-name-handler-alist)
|
|
(message "`epa-file' already enabled")
|
|
(setq file-name-handler-alist
|
|
(cons epa-file-handler file-name-handler-alist))
|
|
(add-hook 'find-file-hook 'epa-file-find-file-hook)
|
|
(setq auto-mode-alist (cons epa-file-auto-mode-alist-entry auto-mode-alist))
|
|
(message "`epa-file' enabled")))
|
|
|
|
;;;###autoload
|
|
(defun epa-file-disable ()
|
|
(interactive)
|
|
(if (memq epa-file-handler file-name-handler-alist)
|
|
(progn
|
|
(setq file-name-handler-alist
|
|
(delq epa-file-handler file-name-handler-alist))
|
|
(remove-hook 'find-file-hook 'epa-file-find-file-hook)
|
|
(setq auto-mode-alist (delq epa-file-auto-mode-alist-entry
|
|
auto-mode-alist))
|
|
(message "`epa-file' disabled"))
|
|
(message "`epa-file' already disabled")))
|
|
|
|
(provide 'epa-file)
|
|
|
|
;; arch-tag: 5715152f-0eb1-4dbc-9008-07098775314d
|
|
;;; epa-file.el ends here
|