lisp/gnus/mml-sec.el

   1 ;;; mml-sec.el --- A package with security functions for MML documents
   2
   3 ;; Copyright (C) 2000, 2001, 2002, 2003, 2004,
   4 ;;   2005, 2006, 2007, 2008 Free Software Foundation, Inc.
   5
   6 ;; Author: Simon Josefsson <simon@josefsson.org>
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software; you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation; either version 3, or (at your option)
  13 ;; any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  22 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  23 ;; Boston, MA 02110-1301, USA.
  24
  25 ;;; Commentary:
  26
  27 ;;; Code:
  28
  29 (require 'mml-smime)
  30 (eval-when-compile (require 'cl))
  31 (autoload 'mml2015-sign "mml2015")
  32 (autoload 'mml2015-encrypt "mml2015")
  33 (autoload 'mml1991-sign "mml1991")
  34 (autoload 'mml1991-encrypt "mml1991")
  35 (autoload 'message-goto-body "message")
  36 (autoload 'mml-insert-tag "mml")
  37
  38 (defvar mml-sign-alist
  39   '(("smime"     mml-smime-sign-buffer     mml-smime-sign-query)
  40     ("pgp"       mml-pgp-sign-buffer       list)
  41     ("pgpauto"   mml-pgpauto-sign-buffer  list)
  42     ("pgpmime"   mml-pgpmime-sign-buffer   list))
  43   "Alist of MIME signer functions.")
  44
  45 (defcustom mml-default-sign-method "pgpmime"
  46   "Default sign method.
  47 The string must have an entry in `mml-sign-alist'."
  48   :version "22.1"
  49   :type '(choice (const "smime")
  50                  (const "pgp")
  51                  (const "pgpauto")
  52                  (const "pgpmime")
  53                  string)
  54   :group 'message)
  55
  56 (defvar mml-encrypt-alist
  57   '(("smime"     mml-smime-encrypt-buffer     mml-smime-encrypt-query)
  58     ("pgp"       mml-pgp-encrypt-buffer       list)
  59     ("pgpauto"   mml-pgpauto-sign-buffer  list)
  60     ("pgpmime"   mml-pgpmime-encrypt-buffer   list))
  61   "Alist of MIME encryption functions.")
  62
  63 (defcustom mml-default-encrypt-method "pgpmime"
  64   "Default encryption method.
  65 The string must have an entry in `mml-encrypt-alist'."
  66   :version "22.1"
  67   :type '(choice (const "smime")
  68                  (const "pgp")
  69                  (const "pgpauto")
  70                  (const "pgpmime")
  71                  string)
  72   :group 'message)
  73
  74 (defcustom mml-signencrypt-style-alist
  75   '(("smime"   separate)
  76     ("pgp"     combined)
  77     ("pgpauto" combined)
  78     ("pgpmime" combined))
  79   "Alist specifying if `signencrypt' results in two separate operations or not.
  80 The first entry indicates the MML security type, valid entries include
  81 the strings \"smime\", \"pgp\", and \"pgpmime\".  The second entry is
  82 a symbol `separate' or `combined' where `separate' means that MML signs
  83 and encrypt messages in a two step process, and `combined' means that MML
  84 signs and encrypt the message in one step.
  85
  86 Note that the output generated by using a `combined' mode is NOT
  87 understood by all PGP implementations, in particular PGP version
  88 2 does not support it!  See Info node `(message)Security' for
  89 details."
  90   :version "22.1"
  91   :group 'message
  92   :type '(repeat (list (choice (const :tag "S/MIME" "smime")
  93                                (const :tag "PGP" "pgp")
  94                                (const :tag "PGP/MIME" "pgpmime")
  95                                (string :tag "User defined"))
  96                        (choice (const :tag "Separate" separate)
  97                                (const :tag "Combined" combined)))))
  98
  99 ;;; Configuration/helper functions
 100
 101 (defun mml-signencrypt-style (method &optional style)
 102   "Function for setting/getting the signencrypt-style used.  Takes two
 103 arguments, the method (e.g. \"pgp\") and optionally the mode
 104 \(e.g. combined).  If the mode is omitted, the current value is returned.
 105
 106 For example, if you prefer to use combined sign & encrypt with
 107 smime, putting the following in your Gnus startup file will
 108 enable that behavior:
 109
 110 \(mml-set-signencrypt-style \"smime\" combined)
 111
 112 You can also customize or set `mml-signencrypt-style-alist' instead."
 113   (let ((style-item (assoc method mml-signencrypt-style-alist)))
 114     (if style-item
 115         (if (or (eq style 'separate)
 116                 (eq style 'combined))
 117             ;; valid style setting?
 118             (setf (second style-item) style)
 119           ;; otherwise, just return the current value
 120           (second style-item))
 121       (message "Warning, attempt to set invalid signencrypt style"))))
 122
 123 ;;; Security functions
 124
 125 (defun mml-smime-sign-buffer (cont)
 126   (or (mml-smime-sign cont)
 127       (error "Signing failed... inspect message logs for errors")))
 128
 129 (defun mml-smime-encrypt-buffer (cont &optional sign)
 130   (when sign
 131     (message "Combined sign and encrypt S/MIME not support yet")
 132     (sit-for 1))
 133   (or (mml-smime-encrypt cont)
 134       (error "Encryption failed... inspect message logs for errors")))
 135
 136 (defun mml-pgp-sign-buffer (cont)
 137   (or (mml1991-sign cont)
 138       (error "Signing failed... inspect message logs for errors")))
 139
 140 (defun mml-pgp-encrypt-buffer (cont &optional sign)
 141   (or (mml1991-encrypt cont sign)
 142       (error "Encryption failed... inspect message logs for errors")))
 143
 144 (defun mml-pgpmime-sign-buffer (cont)
 145   (or (mml2015-sign cont)
 146       (error "Signing failed... inspect message logs for errors")))
 147
 148 (defun mml-pgpmime-encrypt-buffer (cont &optional sign)
 149   (or (mml2015-encrypt cont sign)
 150       (error "Encryption failed... inspect message logs for errors")))
 151
 152 (defun mml-pgpauto-sign-buffer (cont)
 153   (message-goto-body)
 154   (or (if (re-search-backward "Content-Type: *multipart/.*" nil t) ; there must be a better way...
 155           (mml2015-sign cont)
 156         (mml1991-sign cont))
 157       (error "Encryption failed... inspect message logs for errors")))
 158
 159 (defun mml-pgpauto-encrypt-buffer (cont &optional sign)
 160   (message-goto-body)
 161   (or (if (re-search-backward "Content-Type: *multipart/.*" nil t) ; there must be a better way...
 162           (mml2015-encrypt cont sign)
 163         (mml1991-encrypt cont sign))
 164       (error "Encryption failed... inspect message logs for errors")))
 165
 166 (defun mml-secure-part (method &optional sign)
 167   (save-excursion
 168     (let ((tags (funcall (nth 2 (assoc method (if sign mml-sign-alist
 169                                                 mml-encrypt-alist))))))
 170       (cond ((re-search-backward
 171               "<#\\(multipart\\|part\\|external\\|mml\\)" nil t)
 172              (goto-char (match-end 0))
 173              (insert (if sign " sign=" " encrypt=") method)
 174              (while tags
 175                (let ((key (pop tags))
 176                      (value (pop tags)))
 177                  (when value
 178                    ;; Quote VALUE if it contains suspicious characters.
 179                    (when (string-match "[\"'\\~/*;() \t\n]" value)
 180                      (setq value (prin1-to-string value)))
 181                    (insert (format " %s=%s" key value))))))
 182             ((or (re-search-backward
 183                   (concat "^" (regexp-quote mail-header-separator) "\n") nil t)
 184                  (re-search-forward
 185                   (concat "^" (regexp-quote mail-header-separator) "\n") nil t))
 186              (goto-char (match-end 0))
 187              (apply 'mml-insert-tag 'part (cons (if sign 'sign 'encrypt)
 188                                                 (cons method tags))))
 189             (t (error "The message is corrupted. No mail header separator"))))))
 190
 191 (defvar mml-secure-method
 192   (if (equal mml-default-encrypt-method mml-default-sign-method)
 193       mml-default-sign-method
 194     "pgpmime")
 195   "Current security method.  Internal variable.")
 196
 197 (defun mml-secure-sign (&optional method)
 198   "Add MML tags to sign this MML part.
 199 Use METHOD if given.  Else use `mml-secure-method' or
 200 `mml-default-sign-method'."
 201   (interactive)
 202   (mml-secure-part
 203    (or method mml-secure-method mml-default-sign-method)
 204    'sign))
 205
 206 (defun mml-secure-encrypt (&optional method)
 207   "Add MML tags to encrypt this MML part.
 208 Use METHOD if given.  Else use `mml-secure-method' or
 209 `mml-default-sign-method'."
 210   (interactive)
 211   (mml-secure-part
 212    (or method mml-secure-method mml-default-sign-method)))
 213
 214 (defun mml-secure-sign-pgp ()
 215   "Add MML tags to PGP sign this MML part."
 216   (interactive)
 217   (mml-secure-part "pgp" 'sign))
 218
 219 (defun mml-secure-sign-pgpauto ()
 220   "Add MML tags to PGP-auto sign this MML part."
 221   (interactive)
 222   (mml-secure-part "pgpauto" 'sign))
 223
 224 (defun mml-secure-sign-pgpmime ()
 225   "Add MML tags to PGP/MIME sign this MML part."
 226   (interactive)
 227   (mml-secure-part "pgpmime" 'sign))
 228
 229 (defun mml-secure-sign-smime ()
 230   "Add MML tags to S/MIME sign this MML part."
 231   (interactive)
 232   (mml-secure-part "smime" 'sign))
 233
 234 (defun mml-secure-encrypt-pgp ()
 235   "Add MML tags to PGP encrypt this MML part."
 236   (interactive)
 237   (mml-secure-part "pgp"))
 238
 239 (defun mml-secure-encrypt-pgpmime ()
 240   "Add MML tags to PGP/MIME encrypt this MML part."
 241   (interactive)
 242   (mml-secure-part "pgpmime"))
 243
 244 (defun mml-secure-encrypt-smime ()
 245   "Add MML tags to S/MIME encrypt this MML part."
 246   (interactive)
 247   (mml-secure-part "smime"))
 248
 249 ;; defuns that add the proper <#secure ...> tag to the top of the message body
 250 (defun mml-secure-message (method &optional modesym)
 251   (let ((mode (prin1-to-string modesym))
 252         insert-loc)
 253     (mml-unsecure-message)
 254     (save-excursion
 255       (goto-char (point-min))
 256       (cond ((re-search-forward
 257               (concat "^" (regexp-quote mail-header-separator) "\n") nil t)
 258              (goto-char (setq insert-loc (match-end 0)))
 259              (unless (looking-at "<#secure")
 260                (mml-insert-tag
 261                 'secure 'method method 'mode mode)))
 262             (t (error
 263                 "The message is corrupted. No mail header separator"))))
 264     (when (eql insert-loc (point))
 265       (forward-line 1))))
 266
 267 (defun mml-unsecure-message ()
 268   "Remove security related MML tags from message."
 269   (interactive)
 270   (save-excursion
 271     (goto-char (point-max))
 272     (when (re-search-backward "^<#secure.*>\n" nil t)
 273       (delete-region (match-beginning 0) (match-end 0)))))
 274
 275
 276 (defun mml-secure-message-sign (&optional method)
 277   "Add MML tags to sign this MML part.
 278 Use METHOD if given. Else use `mml-secure-method' or
 279 `mml-default-sign-method'."
 280   (interactive)
 281   (mml-secure-part
 282    (or method mml-secure-method mml-default-sign-method)
 283    'sign))
 284
 285 (defun mml-secure-message-sign-encrypt (&optional method)
 286   "Add MML tag to sign and encrypt the entire message.
 287 Use METHOD if given. Else use `mml-secure-method' or
 288 `mml-default-sign-method'."
 289   (interactive)
 290   (mml-secure-message
 291    (or method mml-secure-method mml-default-sign-method)
 292    'signencrypt))
 293
 294 (defun mml-secure-message-encrypt (&optional method)
 295   "Add MML tag to encrypt the entire message.
 296 Use METHOD if given. Else use `mml-secure-method' or
 297 `mml-default-sign-method'."
 298   (interactive)
 299   (mml-secure-message
 300    (or method mml-secure-method mml-default-sign-method)
 301    'encrypt))
 302
 303 (defun mml-secure-message-sign-smime ()
 304   "Add MML tag to encrypt/sign the entire message."
 305   (interactive)
 306   (mml-secure-message "smime" 'sign))
 307
 308 (defun mml-secure-message-sign-pgp ()
 309   "Add MML tag to encrypt/sign the entire message."
 310   (interactive)
 311   (mml-secure-message "pgp" 'sign))
 312
 313 (defun mml-secure-message-sign-pgpmime ()
 314   "Add MML tag to encrypt/sign the entire message."
 315   (interactive)
 316   (mml-secure-message "pgpmime" 'sign))
 317
 318 (defun mml-secure-message-sign-pgpauto ()
 319   "Add MML tag to encrypt/sign the entire message."
 320   (interactive)
 321   (mml-secure-message "pgpauto" 'sign))
 322
 323 (defun mml-secure-message-encrypt-smime (&optional dontsign)
 324   "Add MML tag to encrypt and sign the entire message.
 325 If called with a prefix argument, only encrypt (do NOT sign)."
 326   (interactive "P")
 327   (mml-secure-message "smime" (if dontsign 'encrypt 'signencrypt)))
 328
 329 (defun mml-secure-message-encrypt-pgp (&optional dontsign)
 330   "Add MML tag to encrypt and sign the entire message.
 331 If called with a prefix argument, only encrypt (do NOT sign)."
 332   (interactive "P")
 333   (mml-secure-message "pgp" (if dontsign 'encrypt 'signencrypt)))
 334
 335 (defun mml-secure-message-encrypt-pgpmime (&optional dontsign)
 336   "Add MML tag to encrypt and sign the entire message.
 337 If called with a prefix argument, only encrypt (do NOT sign)."
 338   (interactive "P")
 339   (mml-secure-message "pgpmime" (if dontsign 'encrypt 'signencrypt)))
 340
 341 (defun mml-secure-message-encrypt-pgpauto (&optional dontsign)
 342   "Add MML tag to encrypt and sign the entire message.
 343 If called with a prefix argument, only encrypt (do NOT sign)."
 344   (interactive "P")
 345   (mml-secure-message "pgpauto" (if dontsign 'encrypt 'signencrypt)))
 346
 347 (provide 'mml-sec)
 348
 349 ;;; arch-tag: 111c56e7-df5e-4287-87d7-93ed2911ec6c
 350 ;;; mml-sec.el ends here