lisp/mml2015.el

   1 ;;; mml2015.el --- MIME Security with Pretty Good Privacy (PGP)
   2
   3 ;; Copyright (C) 2000-2016 Free Software Foundation, Inc.
   4
   5 ;; Author: Shenghuo Zhu <zsh@cs.rochester.edu>
   6 ;; Keywords: PGP MIME MML
   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 of the License, or
  13 ;; (at your option) 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.  If not, see <http://www.gnu.org/licenses/>.
  22
  23 ;;; Commentary:
  24
  25 ;; RFC 2015 is updated by RFC 3156, this file should be compatible
  26 ;; with both.
  27
  28 ;;; Code:
  29
  30 (eval-and-compile
  31   (if (locate-library "password-cache")
  32       (require 'password-cache)
  33     (require 'password)))
  34
  35 (eval-when-compile (require 'cl))
  36 (require 'mm-decode)
  37 (require 'mm-util)
  38 (require 'mml)
  39 (require 'mml-sec)
  40
  41 (defvar mc-pgp-always-sign)
  42
  43 (declare-function epg-check-configuration "ext:epg-config"
  44                   (config &optional minimum-version))
  45 (declare-function epg-configuration "ext:epg-config" ())
  46
  47 ;; Maybe this should be in eg mml-sec.el (and have a different name).
  48 ;; Then mml1991 would not need to require mml2015, and mml1991-use
  49 ;; could be removed.
  50 (defvar mml2015-use (or
  51                      (progn
  52                        (ignore-errors (require 'epg-config))
  53                        (and (fboundp 'epg-check-configuration)
  54                            'epg))
  55                      (progn
  56                        (let ((abs-file (locate-library "pgg")))
  57                          ;; Don't load PGG if it is marked as obsolete
  58                          ;; (Emacs 24).
  59                          (when (and abs-file
  60                                     (not (string-match "/obsolete/[^/]*\\'"
  61                                                        abs-file)))
  62                            (ignore-errors (require 'pgg))
  63                            (and (fboundp 'pgg-sign-region)
  64                                 'pgg))))
  65                      (progn (ignore-errors
  66                               (load "mc-toplev"))
  67                             (and (fboundp 'mc-encrypt-generic)
  68                                  (fboundp 'mc-sign-generic)
  69                                  (fboundp 'mc-cleanup-recipient-headers)
  70                                  'mailcrypt)))
  71   "The package used for PGP/MIME.
  72 Valid packages include `epg', `pgg' and `mailcrypt'.")
  73
  74 ;; Something is not RFC2015.
  75 (defvar mml2015-function-alist
  76   '((mailcrypt mml2015-mailcrypt-sign
  77                mml2015-mailcrypt-encrypt
  78                mml2015-mailcrypt-verify
  79                mml2015-mailcrypt-decrypt
  80                mml2015-mailcrypt-clear-verify
  81                mml2015-mailcrypt-clear-decrypt)
  82     (pgg mml2015-pgg-sign
  83          mml2015-pgg-encrypt
  84          mml2015-pgg-verify
  85          mml2015-pgg-decrypt
  86          mml2015-pgg-clear-verify
  87          mml2015-pgg-clear-decrypt)
  88     (epg mml2015-epg-sign
  89          mml2015-epg-encrypt
  90          mml2015-epg-verify
  91          mml2015-epg-decrypt
  92          mml2015-epg-clear-verify
  93          mml2015-epg-clear-decrypt))
  94   "Alist of PGP/MIME functions.")
  95
  96 (defvar mml2015-result-buffer nil)
  97
  98 (defcustom mml2015-unabbrev-trust-alist
  99   '(("TRUST_UNDEFINED" . nil)
 100     ("TRUST_NEVER"     . nil)
 101     ("TRUST_MARGINAL"  . t)
 102     ("TRUST_FULLY"     . t)
 103     ("TRUST_ULTIMATE"  . t))
 104   "Map GnuPG trust output values to a boolean saying if you trust the key."
 105   :version "22.1"
 106   :group 'mime-security
 107   :type '(repeat (cons (regexp :tag "GnuPG output regexp")
 108                        (boolean :tag "Trust key"))))
 109
 110 (defcustom mml2015-cache-passphrase mml-secure-cache-passphrase
 111   "If t, cache passphrase."
 112   :group 'mime-security
 113   :type 'boolean)
 114 (make-obsolete-variable 'mml2015-cache-passphrase
 115                         'mml-secure-cache-passphrase
 116                         "25.0.50")
 117
 118 (defcustom mml2015-passphrase-cache-expiry mml-secure-passphrase-cache-expiry
 119   "How many seconds the passphrase is cached.
 120 Whether the passphrase is cached at all is controlled by
 121 `mml2015-cache-passphrase'."
 122   :group 'mime-security
 123   :type 'integer)
 124 (make-obsolete-variable 'mml2015-passphrase-cache-expiry
 125                         'mml-secure-passphrase-cache-expiry
 126                         "25.0.50")
 127
 128 (defcustom mml2015-signers nil
 129   "A list of your own key ID(s) which will be used to sign a message.
 130 If set, it overrides the setting of `mml2015-sign-with-sender'."
 131   :group 'mime-security
 132   :type '(repeat (string :tag "Key ID")))
 133
 134 (defcustom mml2015-sign-with-sender nil
 135   "If t, use message sender so find a key to sign with."
 136   :group 'mime-security
 137   :type 'boolean
 138   :version "24.1")
 139
 140 (defcustom mml2015-encrypt-to-self nil
 141   "If t, add your own key ID to recipient list when encryption."
 142   :group 'mime-security
 143   :type 'boolean)
 144
 145 (defcustom mml2015-always-trust t
 146   "If t, GnuPG skip key validation on encryption."
 147   :group 'mime-security
 148   :type 'boolean)
 149
 150 (defcustom mml2015-maximum-key-image-dimension 64
 151   "The maximum dimension (width or height) of any key images."
 152   :version "24.4"
 153   :group 'mime-security
 154   :type 'integer)
 155
 156 (defcustom mml2015-display-key-image t
 157   "If t, try to display key images."
 158   :version "24.5"
 159   :group 'mime-security
 160   :type 'boolean)
 161
 162 ;; Extract plaintext from cleartext signature.  IMO, this kind of task
 163 ;; should be done by GnuPG rather than Elisp, but older PGP backends
 164 ;; (such as Mailcrypt, and PGG) discard the output from GnuPG.
 165 (defun mml2015-extract-cleartext-signature ()
 166   ;; Daiki Ueno in
 167   ;; <54a15d860801080142l70b95d7dkac4bf51a86196011@mail.gmail.com>: ``I still
 168   ;; believe that the right way is to use the plaintext output from GnuPG as
 169   ;; it is, and mml2015-extract-cleartext-signature is just a kludge for
 170   ;; misdesigned libraries like PGG, which have no ability to do that.  So, I
 171   ;; think it should not have descriptive documentation.''
 172   ;;
 173   ;; This function doesn't handle NotDashEscaped correctly.  EasyPG handles it
 174   ;; correctly.
 175   ;; http://thread.gmane.org/gmane.emacs.gnus.general/66062/focus=66082
 176   ;; http://thread.gmane.org/gmane.emacs.gnus.general/65087/focus=65109
 177   (goto-char (point-min))
 178   (forward-line)
 179   ;; We need to be careful not to strip beyond the armor headers.
 180   ;; Previously, an attacker could replace the text inside our
 181   ;; markup with trailing garbage by injecting whitespace into the
 182   ;; message.
 183   (while (looking-at "Hash:")           ; The only header allowed in cleartext
 184     (forward-line))                     ; signatures according to RFC2440.
 185   (when (looking-at "[\t ]*$")
 186     (forward-line))
 187   (delete-region (point-min) (point))
 188   (if (re-search-forward "^-----BEGIN PGP SIGNATURE-----" nil t)
 189       (delete-region (match-beginning 0) (point-max)))
 190   (goto-char (point-min))
 191   (while (re-search-forward "^- " nil t)
 192     (replace-match "" t t)
 193     (forward-line 1)))
 194
 195 ;;; mailcrypt wrapper
 196
 197 (autoload 'mailcrypt-decrypt "mailcrypt")
 198 (autoload 'mailcrypt-verify "mailcrypt")
 199 (autoload 'mc-pgp-always-sign "mailcrypt")
 200 (autoload 'mc-encrypt-generic "mc-toplev")
 201 (autoload 'mc-cleanup-recipient-headers "mc-toplev")
 202 (autoload 'mc-sign-generic "mc-toplev")
 203
 204 (defvar mml2015-decrypt-function 'mailcrypt-decrypt)
 205 (defvar mml2015-verify-function 'mailcrypt-verify)
 206
 207 (defun mml2015-format-error (err)
 208   (if (stringp (cadr err))
 209       (cadr err)
 210     (format "%S" (cdr err))))
 211
 212 (defun mml2015-mailcrypt-decrypt (handle ctl)
 213   (catch 'error
 214     (let (child handles result)
 215       (unless (setq child (mm-find-part-by-type
 216                            (cdr handle)
 217                            "application/octet-stream" nil t))
 218         (mm-set-handle-multipart-parameter
 219          mm-security-handle 'gnus-info "Corrupted")
 220         (throw 'error handle))
 221       (with-temp-buffer
 222         (mm-insert-part child)
 223         (setq result
 224               (condition-case err
 225                   (funcall mml2015-decrypt-function)
 226                 (error
 227                  (mm-set-handle-multipart-parameter
 228                   mm-security-handle 'gnus-details (mml2015-format-error err))
 229                  nil)
 230                 (quit
 231                  (mm-set-handle-multipart-parameter
 232                   mm-security-handle 'gnus-details "Quit.")
 233                  nil)))
 234         (unless (car result)
 235           (mm-set-handle-multipart-parameter
 236            mm-security-handle 'gnus-info "Failed")
 237           (throw 'error handle))
 238         (setq handles (mm-dissect-buffer t)))
 239       (mm-destroy-parts handle)
 240       (mm-set-handle-multipart-parameter
 241        mm-security-handle 'gnus-info
 242        (concat "OK"
 243                (let ((sig (with-current-buffer mml2015-result-buffer
 244                             (mml2015-gpg-extract-signature-details))))
 245                  (concat ", Signer: " sig))))
 246       (if (listp (car handles))
 247           handles
 248         (list handles)))))
 249
 250 (defun mml2015-gpg-pretty-print-fpr (fingerprint)
 251   (let* ((result "")
 252          (fpr-length (string-width fingerprint))
 253          (n-slice 0)
 254          slice)
 255     (setq fingerprint (string-to-list fingerprint))
 256     (while fingerprint
 257       (setq fpr-length (- fpr-length 4))
 258       (setq slice (butlast fingerprint fpr-length))
 259       (setq fingerprint (nthcdr 4 fingerprint))
 260       (setq n-slice (1+ n-slice))
 261       (setq result
 262             (concat
 263              result
 264              (case n-slice
 265                (1  slice)
 266                (otherwise (concat " " slice))))))
 267     result))
 268
 269 (defun mml2015-gpg-extract-signature-details ()
 270   (goto-char (point-min))
 271   (let* ((expired (re-search-forward
 272                    "^\\[GNUPG:\\] SIGEXPIRED$"
 273                    nil t))
 274          (signer (and (re-search-forward
 275                        "^\\[GNUPG:\\] GOODSIG \\([0-9A-Za-z]*\\) \\(.*\\)$"
 276                        nil t)
 277                       (cons (match-string 1) (match-string 2))))
 278          (fprint (and (re-search-forward
 279                        "^\\[GNUPG:\\] VALIDSIG \\([0-9a-zA-Z]*\\) "
 280                        nil t)
 281                       (match-string 1)))
 282          (trust  (and (re-search-forward
 283                        "^\\[GNUPG:\\] \\(TRUST_.*\\)$"
 284                        nil t)
 285                       (match-string 1)))
 286          (trust-good-enough-p
 287           (cdr (assoc trust mml2015-unabbrev-trust-alist))))
 288     (cond ((and signer fprint)
 289            (concat (cdr signer)
 290                    (unless trust-good-enough-p
 291                      (concat "\nUntrusted, Fingerprint: "
 292                              (mml2015-gpg-pretty-print-fpr fprint)))
 293                    (when expired
 294                      (format "\nWARNING: Signature from expired key (%s)"
 295                              (car signer)))))
 296           ((re-search-forward
 297             "^\\(gpg: \\)?Good signature from \"\\(.*\\)\"$" nil t)
 298            (match-string 2))
 299           (t
 300            "From unknown user"))))
 301
 302 (defun mml2015-mailcrypt-clear-decrypt ()
 303   (let (result)
 304     (setq result
 305           (condition-case err
 306               (funcall mml2015-decrypt-function)
 307             (error
 308              (mm-set-handle-multipart-parameter
 309               mm-security-handle 'gnus-details (mml2015-format-error err))
 310              nil)
 311             (quit
 312              (mm-set-handle-multipart-parameter
 313               mm-security-handle 'gnus-details "Quit.")
 314              nil)))
 315     (if (car result)
 316         (mm-set-handle-multipart-parameter
 317          mm-security-handle 'gnus-info "OK")
 318       (mm-set-handle-multipart-parameter
 319        mm-security-handle 'gnus-info "Failed"))))
 320
 321 (defun mml2015-fix-micalg (alg)
 322   (and alg
 323        ;; Mutt/1.2.5i has seen sending micalg=php-sha1
 324        (upcase (if (string-match "^p[gh]p-" alg)
 325                    (substring alg (match-end 0))
 326                  alg))))
 327
 328 (defun mml2015-mailcrypt-verify (handle ctl)
 329   (catch 'error
 330     (let (part)
 331       (unless (setq part (mm-find-raw-part-by-type
 332                           ctl (or (mm-handle-multipart-ctl-parameter
 333                                    ctl 'protocol)
 334                                   "application/pgp-signature")
 335                           t))
 336         (mm-set-handle-multipart-parameter
 337          mm-security-handle 'gnus-info "Corrupted")
 338         (throw 'error handle))
 339       (with-temp-buffer
 340         (insert "-----BEGIN PGP SIGNED MESSAGE-----\n")
 341         (insert (format "Hash: %s\n\n"
 342                         (or (mml2015-fix-micalg
 343                              (mm-handle-multipart-ctl-parameter
 344                               ctl 'micalg))
 345                             "SHA1")))
 346         (save-restriction
 347           (narrow-to-region (point) (point))
 348           (insert part "\n")
 349           (goto-char (point-min))
 350           (while (not (eobp))
 351             (if (looking-at "^-")
 352                 (insert "- "))
 353             (forward-line)))
 354         (unless (setq part (mm-find-part-by-type
 355                             (cdr handle) "application/pgp-signature" nil t))
 356           (mm-set-handle-multipart-parameter
 357            mm-security-handle 'gnus-info "Corrupted")
 358           (throw 'error handle))
 359         (save-restriction
 360           (narrow-to-region (point) (point))
 361           (mm-insert-part part)
 362           (goto-char (point-min))
 363           (if (re-search-forward "^-----BEGIN PGP [^-]+-----\r?$" nil t)
 364               (replace-match "-----BEGIN PGP SIGNATURE-----" t t))
 365           (if (re-search-forward "^-----END PGP [^-]+-----\r?$" nil t)
 366               (replace-match "-----END PGP SIGNATURE-----" t t)))
 367         (let ((mc-gpg-debug-buffer (get-buffer-create " *gnus gpg debug*")))
 368           (unless (condition-case err
 369                       (prog1
 370                           (funcall mml2015-verify-function)
 371                         (if (get-buffer " *mailcrypt stderr temp")
 372                             (mm-set-handle-multipart-parameter
 373                              mm-security-handle 'gnus-details
 374                              (with-current-buffer " *mailcrypt stderr temp"
 375                                (buffer-string))))
 376                         (if (get-buffer " *mailcrypt stdout temp")
 377                             (kill-buffer " *mailcrypt stdout temp"))
 378                         (if (get-buffer " *mailcrypt stderr temp")
 379                             (kill-buffer " *mailcrypt stderr temp"))
 380                         (if (get-buffer " *mailcrypt status temp")
 381                             (kill-buffer " *mailcrypt status temp"))
 382                         (if (get-buffer mc-gpg-debug-buffer)
 383                             (kill-buffer mc-gpg-debug-buffer)))
 384                     (error
 385                      (mm-set-handle-multipart-parameter
 386                       mm-security-handle 'gnus-details (mml2015-format-error err))
 387                      nil)
 388                     (quit
 389                      (mm-set-handle-multipart-parameter
 390                       mm-security-handle 'gnus-details "Quit.")
 391                      nil))
 392             (mm-set-handle-multipart-parameter
 393              mm-security-handle 'gnus-info "Failed")
 394             (throw 'error handle))))
 395       (mm-set-handle-multipart-parameter
 396        mm-security-handle 'gnus-info "OK")
 397       handle)))
 398
 399 (defun mml2015-mailcrypt-clear-verify ()
 400   (let ((mc-gpg-debug-buffer (get-buffer-create " *gnus gpg debug*")))
 401     (if (condition-case err
 402             (prog1
 403                 (funcall mml2015-verify-function)
 404               (if (get-buffer " *mailcrypt stderr temp")
 405                   (mm-set-handle-multipart-parameter
 406                    mm-security-handle 'gnus-details
 407                    (with-current-buffer " *mailcrypt stderr temp"
 408                      (buffer-string))))
 409               (if (get-buffer " *mailcrypt stdout temp")
 410                   (kill-buffer " *mailcrypt stdout temp"))
 411               (if (get-buffer " *mailcrypt stderr temp")
 412                   (kill-buffer " *mailcrypt stderr temp"))
 413               (if (get-buffer " *mailcrypt status temp")
 414                   (kill-buffer " *mailcrypt status temp"))
 415               (if (get-buffer mc-gpg-debug-buffer)
 416                   (kill-buffer mc-gpg-debug-buffer)))
 417           (error
 418            (mm-set-handle-multipart-parameter
 419             mm-security-handle 'gnus-details (mml2015-format-error err))
 420            nil)
 421           (quit
 422            (mm-set-handle-multipart-parameter
 423             mm-security-handle 'gnus-details "Quit.")
 424            nil))
 425         (mm-set-handle-multipart-parameter
 426          mm-security-handle 'gnus-info "OK")
 427       (mm-set-handle-multipart-parameter
 428        mm-security-handle 'gnus-info "Failed")))
 429   (mml2015-extract-cleartext-signature))
 430
 431 (defun mml2015-mailcrypt-sign (cont)
 432   (mc-sign-generic (message-options-get 'message-sender)
 433                    nil nil nil nil)
 434   (let ((boundary (mml-compute-boundary cont))
 435         hash point)
 436     (goto-char (point-min))
 437     (unless (re-search-forward "^-----BEGIN PGP SIGNED MESSAGE-----\r?$" nil t)
 438       (error "Cannot find signed begin line"))
 439     (goto-char (match-beginning 0))
 440     (forward-line 1)
 441     (unless (looking-at "Hash:[ \t]*\\([a-zA-Z0-9]+\\)")
 442       (error "Cannot not find PGP hash"))
 443     (setq hash (match-string 1))
 444     (unless (re-search-forward "^$" nil t)
 445       (error "Cannot not find PGP message"))
 446     (forward-line 1)
 447     (delete-region (point-min) (point))
 448     (insert (format "Content-Type: multipart/signed; boundary=\"%s\";\n"
 449                     boundary))
 450     (insert (format "\tmicalg=pgp-%s; protocol=\"application/pgp-signature\"\n"
 451                     (downcase hash)))
 452     (insert (format "\n--%s\n" boundary))
 453     (setq point (point))
 454     (goto-char (point-max))
 455     (unless (re-search-backward "^-----END PGP SIGNATURE-----\r?$" nil t)
 456       (error "Cannot find signature part"))
 457     (replace-match "-----END PGP MESSAGE-----" t t)
 458     (goto-char (match-beginning 0))
 459     (unless (re-search-backward "^-----BEGIN PGP SIGNATURE-----\r?$"
 460                                 nil t)
 461       (error "Cannot find signature part"))
 462     (replace-match "-----BEGIN PGP MESSAGE-----" t t)
 463     (goto-char (match-beginning 0))
 464     (save-restriction
 465       (narrow-to-region point (point))
 466       (goto-char point)
 467       (while (re-search-forward "^- -" nil t)
 468         (replace-match "-" t t))
 469       (goto-char (point-max)))
 470     (insert (format "--%s\n" boundary))
 471     (insert "Content-Type: application/pgp-signature\n\n")
 472     (goto-char (point-max))
 473     (insert (format "--%s--\n" boundary))
 474     (goto-char (point-max))))
 475
 476 ;; We require mm-decode, which requires mm-bodies, which autoloads
 477 ;; message-options-get (!).
 478 (declare-function message-options-set "message" (symbol value))
 479
 480 (defun mml2015-mailcrypt-encrypt (cont &optional sign)
 481   (let ((mc-pgp-always-sign
 482          (or mc-pgp-always-sign
 483              sign
 484              (eq t (or (message-options-get 'message-sign-encrypt)
 485                        (message-options-set
 486                         'message-sign-encrypt
 487                         (or (y-or-n-p "Sign the message? ")
 488                             'not))))
 489              'never)))
 490     (mm-with-unibyte-current-buffer
 491       (mc-encrypt-generic
 492        (or (message-options-get 'message-recipients)
 493            (message-options-set 'message-recipients
 494                               (mc-cleanup-recipient-headers
 495                                (read-string "Recipients: "))))
 496        nil nil nil
 497        (message-options-get 'message-sender))))
 498   (goto-char (point-min))
 499   (unless (looking-at "-----BEGIN PGP MESSAGE-----")
 500     (error "Fail to encrypt the message"))
 501   (let ((boundary (mml-compute-boundary cont)))
 502     (insert (format "Content-Type: multipart/encrypted; boundary=\"%s\";\n"
 503                     boundary))
 504     (insert "\tprotocol=\"application/pgp-encrypted\"\n\n")
 505     (insert (format "--%s\n" boundary))
 506     (insert "Content-Type: application/pgp-encrypted\n\n")
 507     (insert "Version: 1\n\n")
 508     (insert (format "--%s\n" boundary))
 509     (insert "Content-Type: application/octet-stream\n\n")
 510     (goto-char (point-max))
 511     (insert (format "--%s--\n" boundary))
 512     (goto-char (point-max))))
 513
 514 ;;; pgg wrapper
 515
 516 (defvar pgg-default-user-id)
 517 (defvar pgg-errors-buffer)
 518 (defvar pgg-output-buffer)
 519
 520 (autoload 'pgg-decrypt-region "pgg")
 521 (autoload 'pgg-verify-region "pgg")
 522 (autoload 'pgg-sign-region "pgg")
 523 (autoload 'pgg-encrypt-region "pgg")
 524 (autoload 'pgg-parse-armor "pgg-parse")
 525
 526 (defun mml2015-pgg-decrypt (handle ctl)
 527   (catch 'error
 528     (let ((pgg-errors-buffer mml2015-result-buffer)
 529           child handles result decrypt-status)
 530       (unless (setq child (mm-find-part-by-type
 531                            (cdr handle)
 532                            "application/octet-stream" nil t))
 533         (mm-set-handle-multipart-parameter
 534          mm-security-handle 'gnus-info "Corrupted")
 535         (throw 'error handle))
 536       (with-temp-buffer
 537         (mm-insert-part child)
 538         (if (condition-case err
 539                 (prog1
 540                     (pgg-decrypt-region (point-min) (point-max))
 541                   (setq decrypt-status
 542                         (with-current-buffer mml2015-result-buffer
 543                           (buffer-string)))
 544                   (mm-set-handle-multipart-parameter
 545                    mm-security-handle 'gnus-details
 546                    decrypt-status))
 547               (error
 548                (mm-set-handle-multipart-parameter
 549                 mm-security-handle 'gnus-details (mml2015-format-error err))
 550                nil)
 551               (quit
 552                (mm-set-handle-multipart-parameter
 553                 mm-security-handle 'gnus-details "Quit.")
 554                nil))
 555             (with-current-buffer pgg-output-buffer
 556               (goto-char (point-min))
 557               (while (search-forward "\r\n" nil t)
 558                 (replace-match "\n" t t))
 559               (setq handles (mm-dissect-buffer t))
 560               (mm-destroy-parts handle)
 561               (mm-set-handle-multipart-parameter
 562                mm-security-handle 'gnus-info "OK")
 563               (mm-set-handle-multipart-parameter
 564                mm-security-handle 'gnus-details
 565                (concat decrypt-status
 566                        (when (stringp (car handles))
 567                          "\n" (mm-handle-multipart-ctl-parameter
 568                                handles 'gnus-details))))
 569               (if (listp (car handles))
 570                   handles
 571                 (list handles)))
 572           (mm-set-handle-multipart-parameter
 573            mm-security-handle 'gnus-info "Failed")
 574           (throw 'error handle))))))
 575
 576 (defun mml2015-pgg-clear-decrypt ()
 577   (let ((pgg-errors-buffer mml2015-result-buffer))
 578     (if (prog1
 579             (pgg-decrypt-region (point-min) (point-max))
 580           (mm-set-handle-multipart-parameter
 581            mm-security-handle 'gnus-details
 582            (with-current-buffer mml2015-result-buffer
 583              (buffer-string))))
 584         (progn
 585           (erase-buffer)
 586           ;; Treat data which pgg returns as a unibyte string.
 587           (mm-disable-multibyte)
 588           (insert-buffer-substring pgg-output-buffer)
 589           (goto-char (point-min))
 590           (while (search-forward "\r\n" nil t)
 591             (replace-match "\n" t t))
 592           (mm-set-handle-multipart-parameter
 593            mm-security-handle 'gnus-info "OK"))
 594       (mm-set-handle-multipart-parameter
 595        mm-security-handle 'gnus-info "Failed"))))
 596
 597 (defun mml2015-pgg-verify (handle ctl)
 598   (let ((pgg-errors-buffer mml2015-result-buffer)
 599         signature-file part signature)
 600     (if (or (null (setq part (mm-find-raw-part-by-type
 601                               ctl (or (mm-handle-multipart-ctl-parameter
 602                                        ctl 'protocol)
 603                                       "application/pgp-signature")
 604                               t)))
 605             (null (setq signature (mm-find-part-by-type
 606                                    (cdr handle) "application/pgp-signature" nil t))))
 607         (progn
 608           (mm-set-handle-multipart-parameter
 609            mm-security-handle 'gnus-info "Corrupted")
 610           handle)
 611       (with-temp-buffer
 612         (insert part)
 613         ;; Convert <LF> to <CR><LF> in signed text.  If --textmode is
 614         ;; specified when signing, the conversion is not necessary.
 615         (goto-char (point-min))
 616         (end-of-line)
 617         (while (not (eobp))
 618           (unless (eq (char-before) ?\r)
 619             (insert "\r"))
 620           (forward-line)
 621           (end-of-line))
 622         (with-temp-file (setq signature-file (mm-make-temp-file "pgg"))
 623           (mm-insert-part signature))
 624         (if (condition-case err
 625                 (prog1
 626                     (pgg-verify-region (point-min) (point-max)
 627                                        signature-file t)
 628                   (goto-char (point-min))
 629                   (while (search-forward "\r\n" nil t)
 630                     (replace-match "\n" t t))
 631                   (mm-set-handle-multipart-parameter
 632                    mm-security-handle 'gnus-details
 633                    (concat (with-current-buffer pgg-output-buffer
 634                              (buffer-string))
 635                            (with-current-buffer pgg-errors-buffer
 636                              (buffer-string)))))
 637               (error
 638                (mm-set-handle-multipart-parameter
 639                 mm-security-handle 'gnus-details (mml2015-format-error err))
 640                nil)
 641               (quit
 642                (mm-set-handle-multipart-parameter
 643                 mm-security-handle 'gnus-details "Quit.")
 644                nil))
 645             (progn
 646               (delete-file signature-file)
 647               (mm-set-handle-multipart-parameter
 648                mm-security-handle 'gnus-info
 649                (with-current-buffer pgg-errors-buffer
 650                  (mml2015-gpg-extract-signature-details))))
 651           (delete-file signature-file)
 652           (mm-set-handle-multipart-parameter
 653            mm-security-handle 'gnus-info "Failed")))))
 654   handle)
 655
 656 (defun mml2015-pgg-clear-verify ()
 657   (let ((pgg-errors-buffer mml2015-result-buffer)
 658         (text (buffer-string))
 659         (coding-system buffer-file-coding-system))
 660     (if (condition-case err
 661             (prog1
 662                 (mm-with-unibyte-buffer
 663                   (insert (mm-encode-coding-string text coding-system))
 664                   (pgg-verify-region (point-min) (point-max) nil t))
 665               (goto-char (point-min))
 666               (while (search-forward "\r\n" nil t)
 667                 (replace-match "\n" t t))
 668               (mm-set-handle-multipart-parameter
 669                mm-security-handle 'gnus-details
 670                (concat (with-current-buffer pgg-output-buffer
 671                          (buffer-string))
 672                        (with-current-buffer pgg-errors-buffer
 673                          (buffer-string)))))
 674           (error
 675            (mm-set-handle-multipart-parameter
 676             mm-security-handle 'gnus-details (mml2015-format-error err))
 677            nil)
 678           (quit
 679            (mm-set-handle-multipart-parameter
 680             mm-security-handle 'gnus-details "Quit.")
 681            nil))
 682         (mm-set-handle-multipart-parameter
 683          mm-security-handle 'gnus-info
 684          (with-current-buffer pgg-errors-buffer
 685            (mml2015-gpg-extract-signature-details)))
 686       (mm-set-handle-multipart-parameter
 687        mm-security-handle 'gnus-info "Failed")))
 688   (mml2015-extract-cleartext-signature))
 689
 690 (defun mml2015-pgg-sign (cont)
 691   (let ((pgg-errors-buffer mml2015-result-buffer)
 692         (boundary (mml-compute-boundary cont))
 693         (pgg-default-user-id (or (message-options-get 'mml-sender)
 694                                  pgg-default-user-id))
 695         (pgg-text-mode t)
 696         entry)
 697     (unless (pgg-sign-region (point-min) (point-max))
 698       (pop-to-buffer mml2015-result-buffer)
 699       (error "Sign error"))
 700     (goto-char (point-min))
 701     (insert (format "Content-Type: multipart/signed; boundary=\"%s\";\n"
 702                     boundary))
 703     (if (setq entry (assq 2 (pgg-parse-armor
 704                              (with-current-buffer pgg-output-buffer
 705                                (buffer-string)))))
 706         (setq entry (assq 'hash-algorithm (cdr entry))))
 707     (insert (format "\tmicalg=%s; "
 708                     (if (cdr entry)
 709                         (downcase (format "pgp-%s" (cdr entry)))
 710                       "pgp-sha1")))
 711     (insert "protocol=\"application/pgp-signature\"\n")
 712     (insert (format "\n--%s\n" boundary))
 713     (goto-char (point-max))
 714     (insert (format "\n--%s\n" boundary))
 715     (insert "Content-Type: application/pgp-signature\n\n")
 716     (insert-buffer-substring pgg-output-buffer)
 717     (goto-char (point-max))
 718     (insert (format "--%s--\n" boundary))
 719     (goto-char (point-max))))
 720
 721 (defun mml2015-pgg-encrypt (cont &optional sign)
 722   (let ((pgg-errors-buffer mml2015-result-buffer)
 723         (pgg-text-mode t)
 724         (boundary (mml-compute-boundary cont)))
 725     (unless (pgg-encrypt-region (point-min) (point-max)
 726                                 (split-string
 727                                  (or
 728                                   (message-options-get 'message-recipients)
 729                                   (message-options-set 'message-recipients
 730                                                        (read-string "Recipients: ")))
 731                                  "[ \f\t\n\r\v,]+")
 732                                 sign)
 733       (pop-to-buffer mml2015-result-buffer)
 734       (error "Encrypt error"))
 735     (delete-region (point-min) (point-max))
 736     (goto-char (point-min))
 737     (insert (format "Content-Type: multipart/encrypted; boundary=\"%s\";\n"
 738                     boundary))
 739     (insert "\tprotocol=\"application/pgp-encrypted\"\n\n")
 740     (insert (format "--%s\n" boundary))
 741     (insert "Content-Type: application/pgp-encrypted\n\n")
 742     (insert "Version: 1\n\n")
 743     (insert (format "--%s\n" boundary))
 744     (insert "Content-Type: application/octet-stream\n\n")
 745     (insert-buffer-substring pgg-output-buffer)
 746     (goto-char (point-max))
 747     (insert (format "--%s--\n" boundary))
 748     (goto-char (point-max))))
 749
 750 ;;; epg wrapper
 751
 752 (defvar epg-user-id-alist)
 753 (defvar epg-digest-algorithm-alist)
 754 (defvar epg-gpg-program)
 755 (defvar inhibit-redisplay)
 756
 757 (autoload 'epg-make-context "epg")
 758 (autoload 'epg-context-set-armor "epg")
 759 (autoload 'epg-context-set-textmode "epg")
 760 (autoload 'epg-context-set-signers "epg")
 761 (autoload 'epg-context-result-for "epg")
 762 (autoload 'epg-new-signature-digest-algorithm "epg")
 763 (autoload 'epg-list-keys "epg")
 764 (autoload 'epg-decrypt-string "epg")
 765 (autoload 'epg-verify-string "epg")
 766 (autoload 'epg-sign-string "epg")
 767 (autoload 'epg-encrypt-string "epg")
 768 (autoload 'epg-passphrase-callback-function "epg")
 769 (autoload 'epg-context-set-passphrase-callback "epg")
 770 (autoload 'epg-key-sub-key-list "epg")
 771 (autoload 'epg-sub-key-capability "epg")
 772 (autoload 'epg-sub-key-validity "epg")
 773 (autoload 'epg-sub-key-fingerprint "epg")
 774 (autoload 'epg-signature-key-id "epg")
 775 (autoload 'epg-signature-to-string "epg")
 776 (autoload 'epg-key-user-id-list "epg")
 777 (autoload 'epg-user-id-string "epg")
 778 (autoload 'epg-user-id-validity "epg")
 779 (autoload 'epg-configuration "epg-config")
 780 (autoload 'epg-expand-group "epg-config")
 781 (autoload 'epa-select-keys "epa")
 782
 783 (autoload 'gnus-create-image "gnus-ems")
 784
 785 (defun mml2015-epg-key-image (key-id)
 786   "Return the image of a key, if any"
 787   (with-temp-buffer
 788     (mm-set-buffer-multibyte nil)
 789     (let* ((coding-system-for-write 'binary)
 790            (coding-system-for-read 'binary)
 791            (data (shell-command-to-string
 792                   (format "%s --list-options no-show-photos --attribute-fd 3 --list-keys %s 3>&1 >/dev/null 2>&1"
 793                           (shell-quote-argument epg-gpg-program) key-id))))
 794       (when (> (length data) 0)
 795         (insert (substring data 16))
 796         (condition-case nil
 797             (gnus-create-image (buffer-string) nil t)
 798           (error))))))
 799
 800 (autoload 'gnus-rescale-image "gnus-util")
 801
 802 (defun mml2015-epg-key-image-to-string (key-id)
 803   "Return a string with the image of a key, if any"
 804   (let ((key-image (mml2015-epg-key-image key-id)))
 805     (if (not key-image)
 806         ""
 807       (condition-case error
 808           (let ((result "  "))
 809             (put-text-property
 810              1 2 'display
 811              (gnus-rescale-image key-image
 812                                  (cons mml2015-maximum-key-image-dimension
 813                                        mml2015-maximum-key-image-dimension))
 814              result)
 815             result)
 816         (error "")))))
 817
 818 (defun mml2015-epg-signature-to-string (signature)
 819   (concat (epg-signature-to-string signature)
 820           (when mml2015-display-key-image
 821             (mml2015-epg-key-image-to-string (epg-signature-key-id signature)))))
 822
 823 (defun mml2015-epg-verify-result-to-string (verify-result)
 824   (mapconcat #'mml2015-epg-signature-to-string verify-result "\n"))
 825
 826 (defun mml2015-epg-decrypt (handle ctl)
 827   (catch 'error
 828     (let ((inhibit-redisplay t)
 829           context plain child handles result decrypt-status)
 830       (unless (setq child (mm-find-part-by-type
 831                            (cdr handle)
 832                            "application/octet-stream" nil t))
 833         (mm-set-handle-multipart-parameter
 834          mm-security-handle 'gnus-info "Corrupted")
 835         (throw 'error handle))
 836       (setq context (epg-make-context))
 837       (if (or mml2015-cache-passphrase mml-secure-cache-passphrase)
 838           (epg-context-set-passphrase-callback
 839            context
 840            (cons 'mml-secure-passphrase-callback 'OpenPGP)))
 841       (condition-case error
 842           (setq plain (epg-decrypt-string context (mm-get-part child))
 843                 mml-secure-secret-key-id-list nil)
 844         (error
 845          (mml-secure-clear-secret-key-id-list)
 846          (mm-set-handle-multipart-parameter
 847           mm-security-handle 'gnus-info "Failed")
 848          (if (eq (car error) 'quit)
 849              (mm-set-handle-multipart-parameter
 850               mm-security-handle 'gnus-details "Quit.")
 851            (mm-set-handle-multipart-parameter
 852             mm-security-handle 'gnus-details (mml2015-format-error error)))
 853          (throw 'error handle)))
 854       (with-temp-buffer
 855         (insert plain)
 856         (goto-char (point-min))
 857         (while (search-forward "\r\n" nil t)
 858           (replace-match "\n" t t))
 859         (setq handles (mm-dissect-buffer t))
 860         (mm-destroy-parts handle)
 861         (if (epg-context-result-for context 'verify)
 862             (mm-set-handle-multipart-parameter
 863              mm-security-handle 'gnus-info
 864              (concat "OK\n"
 865                      (mml2015-epg-verify-result-to-string
 866                       (epg-context-result-for context 'verify))))
 867           (mm-set-handle-multipart-parameter
 868            mm-security-handle 'gnus-info "OK"))
 869         (if (stringp (car handles))
 870             (mm-set-handle-multipart-parameter
 871              mm-security-handle 'gnus-details
 872              (mm-handle-multipart-ctl-parameter handles 'gnus-details))))
 873         (if (listp (car handles))
 874             handles
 875           (list handles)))))
 876
 877 (defun mml2015-epg-clear-decrypt ()
 878   (let ((inhibit-redisplay t)
 879         (context (epg-make-context))
 880         plain)
 881     (if (or mml2015-cache-passphrase mml-secure-cache-passphrase)
 882         (epg-context-set-passphrase-callback
 883          context
 884          (cons 'mml-secure-passphrase-callback 'OpenPGP)))
 885     (condition-case error
 886         (setq plain (epg-decrypt-string context (buffer-string))
 887               mml-secure-secret-key-id-list nil)
 888       (error
 889        (mml-secure-clear-secret-key-id-list)
 890        (mm-set-handle-multipart-parameter
 891         mm-security-handle 'gnus-info "Failed")
 892        (if (eq (car error) 'quit)
 893            (mm-set-handle-multipart-parameter
 894             mm-security-handle 'gnus-details "Quit.")
 895          (mm-set-handle-multipart-parameter
 896           mm-security-handle 'gnus-details (mml2015-format-error error)))))
 897     (when plain
 898       (erase-buffer)
 899       ;; Treat data which epg returns as a unibyte string.
 900       (mm-disable-multibyte)
 901       (insert plain)
 902       (goto-char (point-min))
 903       (while (search-forward "\r\n" nil t)
 904         (replace-match "\n" t t))
 905       (mm-set-handle-multipart-parameter
 906        mm-security-handle 'gnus-info "OK")
 907       (if (epg-context-result-for context 'verify)
 908           (mm-set-handle-multipart-parameter
 909            mm-security-handle 'gnus-details
 910            (mml2015-epg-verify-result-to-string
 911             (epg-context-result-for context 'verify)))))))
 912
 913 (defun mml2015-epg-verify (handle ctl)
 914   (catch 'error
 915     (let ((inhibit-redisplay t)
 916           context plain signature-file part signature)
 917       (when (or (null (setq part (mm-find-raw-part-by-type
 918                                   ctl (or (mm-handle-multipart-ctl-parameter
 919                                            ctl 'protocol)
 920                                           "application/pgp-signature")
 921                                   t)))
 922                 (null (setq signature (mm-find-part-by-type
 923                                        (cdr handle) "application/pgp-signature"
 924                                        nil t))))
 925         (mm-set-handle-multipart-parameter
 926          mm-security-handle 'gnus-info "Corrupted")
 927         (throw 'error handle))
 928       (setq part (mm-replace-in-string part "\n" "\r\n")
 929             signature (mm-get-part signature)
 930             context (epg-make-context))
 931       (condition-case error
 932           (setq plain (epg-verify-string context signature part))
 933         (error
 934          (mm-set-handle-multipart-parameter
 935           mm-security-handle 'gnus-info "Failed")
 936          (if (eq (car error) 'quit)
 937              (mm-set-handle-multipart-parameter
 938               mm-security-handle 'gnus-details "Quit.")
 939            (mm-set-handle-multipart-parameter
 940             mm-security-handle 'gnus-details (mml2015-format-error error)))
 941          (throw 'error handle)))
 942       (mm-set-handle-multipart-parameter
 943        mm-security-handle 'gnus-info
 944        (mml2015-epg-verify-result-to-string
 945         (epg-context-result-for context 'verify)))
 946       handle)))
 947
 948 (defun mml2015-epg-clear-verify ()
 949   (let ((inhibit-redisplay t)
 950         (context (epg-make-context))
 951         (signature (mm-encode-coding-string (buffer-string)
 952                                             coding-system-for-write))
 953         plain)
 954     (condition-case error
 955         (setq plain (epg-verify-string context signature))
 956       (error
 957        (mm-set-handle-multipart-parameter
 958         mm-security-handle 'gnus-info "Failed")
 959        (if (eq (car error) 'quit)
 960            (mm-set-handle-multipart-parameter
 961             mm-security-handle 'gnus-details "Quit.")
 962          (mm-set-handle-multipart-parameter
 963           mm-security-handle 'gnus-details (mml2015-format-error error)))))
 964     (if plain
 965         (progn
 966           (mm-set-handle-multipart-parameter
 967            mm-security-handle 'gnus-info
 968            (mml2015-epg-verify-result-to-string
 969             (epg-context-result-for context 'verify)))
 970           (delete-region (point-min) (point-max))
 971           (insert (mm-decode-coding-string plain coding-system-for-read)))
 972       (mml2015-extract-cleartext-signature))))
 973
 974 (defun mml2015-epg-sign (cont)
 975   (let ((inhibit-redisplay t)
 976         (boundary (mml-compute-boundary cont)))
 977     ;; Signed data must end with a newline (RFC 3156, 5).
 978     (goto-char (point-max))
 979     (unless (bolp)
 980       (insert "\n"))
 981     (let* ((pair (mml-secure-epg-sign 'OpenPGP t))
 982            (signature (car pair))
 983            (micalg (cdr pair)))
 984       (goto-char (point-min))
 985       (insert (format "Content-Type: multipart/signed; boundary=\"%s\";\n"
 986                       boundary))
 987       (if micalg
 988           (insert (format "\tmicalg=pgp-%s; "
 989                           (downcase
 990                            (cdr (assq micalg
 991                                       epg-digest-algorithm-alist))))))
 992       (insert "protocol=\"application/pgp-signature\"\n")
 993       (insert (format "\n--%s\n" boundary))
 994       (goto-char (point-max))
 995       (insert (format "\n--%s\n" boundary))
 996       (insert "Content-Type: application/pgp-signature; name=\"signature.asc\"\n\n")
 997       (insert signature)
 998       (goto-char (point-max))
 999       (insert (format "--%s--\n" boundary))
1000       (goto-char (point-max)))))
1001
1002 (defun mml2015-epg-encrypt (cont &optional sign)
1003   (let* ((inhibit-redisplay t)
1004          (boundary (mml-compute-boundary cont))
1005          (cipher (mml-secure-epg-encrypt 'OpenPGP cont sign)))
1006     (delete-region (point-min) (point-max))
1007     (goto-char (point-min))
1008     (insert (format "Content-Type: multipart/encrypted; boundary=\"%s\";\n"
1009                     boundary))
1010     (insert "\tprotocol=\"application/pgp-encrypted\"\n\n")
1011     (insert (format "--%s\n" boundary))
1012     (insert "Content-Type: application/pgp-encrypted\n\n")
1013     (insert "Version: 1\n\n")
1014     (insert (format "--%s\n" boundary))
1015     (insert "Content-Type: application/octet-stream\n\n")
1016     (insert cipher)
1017     (goto-char (point-max))
1018     (insert (format "--%s--\n" boundary))
1019     (goto-char (point-max))))
1020
1021 ;;; General wrapper
1022
1023 (autoload 'gnus-buffer-live-p "gnus-util")
1024 (autoload 'gnus-get-buffer-create "gnus")
1025
1026 (defun mml2015-clean-buffer ()
1027   (if (gnus-buffer-live-p mml2015-result-buffer)
1028       (with-current-buffer mml2015-result-buffer
1029         (erase-buffer)
1030         t)
1031     (setq mml2015-result-buffer
1032           (gnus-get-buffer-create " *MML2015 Result*"))
1033     nil))
1034
1035 (defsubst mml2015-clear-decrypt-function ()
1036   (nth 6 (assq mml2015-use mml2015-function-alist)))
1037
1038 (defsubst mml2015-clear-verify-function ()
1039   (nth 5 (assq mml2015-use mml2015-function-alist)))
1040
1041 ;;;###autoload
1042 (defun mml2015-decrypt (handle ctl)
1043   (mml2015-clean-buffer)
1044   (let ((func (nth 4 (assq mml2015-use mml2015-function-alist))))
1045     (if func
1046         (funcall func handle ctl)
1047       handle)))
1048
1049 ;;;###autoload
1050 (defun mml2015-decrypt-test (handle ctl)
1051   mml2015-use)
1052
1053 ;;;###autoload
1054 (defun mml2015-verify (handle ctl)
1055   (mml2015-clean-buffer)
1056   (let ((func (nth 3 (assq mml2015-use mml2015-function-alist))))
1057     (if func
1058         (funcall func handle ctl)
1059       handle)))
1060
1061 ;;;###autoload
1062 (defun mml2015-verify-test (handle ctl)
1063   mml2015-use)
1064
1065 ;;;###autoload
1066 (defun mml2015-encrypt (cont &optional sign)
1067   (mml2015-clean-buffer)
1068   (let ((func (nth 2 (assq mml2015-use mml2015-function-alist))))
1069     (if func
1070         (funcall func cont sign)
1071       (error "Cannot find encrypt function"))))
1072
1073 ;;;###autoload
1074 (defun mml2015-sign (cont)
1075   (mml2015-clean-buffer)
1076   (let ((func (nth 1 (assq mml2015-use mml2015-function-alist))))
1077     (if func
1078         (funcall func cont)
1079       (error "Cannot find sign function"))))
1080
1081 ;;;###autoload
1082 (defun mml2015-self-encrypt ()
1083   (mml2015-encrypt nil))
1084
1085 (provide 'mml2015)
1086
1087 ;;; mml2015.el ends here