1 ;;; riece-epg.el --- Encrypt/decrypt messages add-on
2 ;; Copyright (C) 2006 Daiki Ueno
4 ;; Author: Daiki Ueno <ueno@unixuser.org>
5 ;; Keywords: IRC, riece
7 ;; This file is part of Riece.
9 ;; This program is free software; you can redistribute it and/or modify
10 ;; it under the terms of the GNU General Public License as published by
11 ;; the Free Software Foundation; either version 2, or (at your option)
14 ;; This program is distributed in the hope that it will be useful,
15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 ;; GNU General Public License for more details.
19 ;; You should have received a copy of the GNU General Public License
20 ;; along with GNU Emacs; see the file COPYING. If not, write to the
21 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
22 ;; Boston, MA 02110-1301, USA.
26 (require 'riece-message)
27 (require 'riece-identity)
29 (autoload 'widget-convert-button "wid-edit")
30 (autoload 'epg-make-context "epg")
31 (autoload 'epg-decrypt-string "epg")
32 (autoload 'epg-encrypt-string "epg")
33 (autoload 'epg-passphrase-callback-function "epg")
34 (autoload 'epg-context-set-passphrase-callback "epg")
37 (autoload 'riece-command-send-message "riece-commands"))
39 (defgroup riece-epg nil
40 "Encrypt/decrypt messages."
43 (defconst riece-epg-description
44 "Encrypt/decrypt messages.")
46 (defvar riece-epg-passphrase-alist nil)
48 (defun riece-epg-passphrase-callback-function (context key-id identity)
50 (let ((entry (riece-identity-assoc identity riece-epg-passphrase-alist))
52 (or (copy-sequence (cdr entry))
55 (setq entry (list identity)
56 riece-epg-passphrase-alist (cons entry
57 riece-epg-passphrase-alist)))
58 (setq passphrase (epg-passphrase-callback-function context
60 (setcdr entry (copy-sequence passphrase))
62 (epg-passphrase-callback-function context key-id nil)))
64 (defun riece-epg-passphrase-callback-function-for-decrypt (context key-id
67 (let ((entry (riece-identity-assoc identity riece-epg-passphrase-alist)))
69 (copy-sequence (cdr entry))
70 (epg-cancel context)))
71 (epg-passphrase-callback-function context key-id nil)))
73 (defun riece-epg-funcall-clear-passphrase (identity function &rest args)
77 (let ((entry (riece-identity-assoc identity riece-epg-passphrase-alist)))
79 (setq riece-epg-passphrase-alist
80 (delq entry riece-epg-passphrase-alist))))
81 (signal (car error) (cdr error)))))
83 (defun riece-command-enter-encrypted-message ()
84 "Encrypt the current line and send it to the current channel."
86 (let ((context (epg-make-context))
87 (string (buffer-substring (riece-line-beginning-position)
88 (riece-line-end-position))))
89 (epg-context-set-passphrase-callback
91 (cons #'riece-epg-passphrase-callback-function
92 riece-current-channel))
94 (format "PRIVMSG %s :[encrypted:%s]\r\n"
95 (riece-identity-prefix riece-current-channel)
97 (riece-epg-funcall-clear-passphrase
101 (riece-with-server-buffer
102 (riece-identity-server riece-current-channel)
103 (riece-encode-coding-string-for-identity
105 riece-current-channel))
108 (riece-display-message
109 (riece-make-message (riece-current-nickname) riece-current-channel
110 (concat "[decrypted:" string "]") nil t))
111 (let ((next-line-add-newlines t))
114 (defun riece-command-set-passphrase (identity passphrase)
115 "Set PASSPHRASE associated with IDENTITY."
118 (riece-completing-read-identity
120 riece-current-channels nil t nil nil
121 (riece-format-identity riece-current-channel))))
123 (read-passwd (format "Passphrase for %s: "
124 (riece-format-identity identity))))))
125 (let ((entry (riece-identity-assoc identity riece-epg-passphrase-alist)))
126 (if (equal passphrase "")
128 (setq riece-epg-passphrase-alist
129 (delq entry riece-epg-passphrase-alist)))
131 (setcdr entry passphrase)
132 (setq riece-epg-passphrase-alist
133 (cons (cons identity passphrase)
134 riece-epg-passphrase-alist))))))
136 (defun riece-epg-decrypt-string-for-identity (context cipher target)
138 (or (riece-coding-system-for-identity target)
139 riece-default-coding-system)))
140 (riece-with-server-buffer (riece-identity-server target)
141 (decode-coding-string
142 (riece-epg-funcall-clear-passphrase
146 (base64-decode-string cipher))
147 (if (consp coding-system)
151 (defun riece-epg-message-filter (message)
152 (if (get 'riece-epg 'riece-addon-enabled)
153 (when (string-match "\\`\\[encrypted:\\(.*\\)]"
154 (riece-message-text message))
155 (let ((context (epg-make-context))
156 (string (match-string 1 (riece-message-text message))))
157 (epg-context-set-passphrase-callback
159 (cons #'riece-epg-passphrase-callback-function-for-decrypt
160 riece-current-channel))
161 (condition-case error
163 (riece-message-set-text
165 (format "[decrypted:%s]"
166 (riece-epg-decrypt-string-for-identity
167 context string (riece-message-target message)))))
169 (riece-put-text-property-nonsticky
170 0 (length (riece-message-text message))
171 'riece-epg-encryption-target (riece-message-target message)
172 (riece-message-text message))
174 (message "Couldn't decrypt: %s" (cdr error))
175 (message "Couldn't decrypt")))))))
178 (defun riece-epg-add-encrypted-button (start end)
179 (if (and (get 'riece-button 'riece-addon-enabled)
180 (get 'riece-epg 'riece-addon-enabled))
181 (riece-scan-property-region
182 'riece-epg-encryption-target
185 (let ((inhibit-read-only t)
187 (widget-convert-button
189 :help-echo "Click to decrypt"
190 :notify #'riece-epg-encrypted-button-notify
191 (get-text-property start 'riece-epg-encryption-target)))))))
193 (defun riece-epg-encrypted-button-notify (widget &rest ignore)
194 (let* ((from (marker-position (widget-get widget :from)))
195 (to (marker-position (widget-get widget :to)))
196 (target (widget-get widget :value))
197 (cipher (buffer-substring from to))
198 (inhibit-read-only t)
201 (when (string-match "\\`\\[encrypted:\\(.*\\)]" cipher)
202 (setq plain (riece-epg-decrypt-string-for-identity
203 (epg-make-context) (match-string 1 cipher) target))
204 (widget-delete widget)
205 (delete-region from to)
208 (insert "[decrypted:" plain "]")))))
210 (defun riece-epg-requires ()
211 (if (memq 'riece-button riece-addons)
214 (defun riece-epg-insinuate ()
215 (add-hook 'riece-message-filter-functions 'riece-epg-message-filter)
216 (add-hook 'riece-after-insert-functions 'riece-epg-add-encrypted-button))
218 (defun riece-epg-uninstall ()
219 (remove-hook 'riece-message-filter-functions 'riece-epg-message-filter)
220 (remove-hook 'riece-after-insert-functions 'riece-epg-add-encrypted-button))
222 (defvar riece-command-mode-map)
223 (defun riece-epg-enable ()
224 (define-key riece-command-mode-map
225 "\C-ce" 'riece-command-enter-encrypted-message)
226 (define-key riece-command-mode-map
227 "\C-c\C-ec" 'riece-command-set-passphrase))
229 (defun riece-epg-disable ()
230 (define-key riece-command-mode-map
232 (define-key riece-command-mode-map
237 ;;; riece-epg.el ends here