| 1 | ;;; pgg-gpg.el --- GnuPG support for PGG. |
| 2 | |
| 3 | ;; Copyright (C) 1999, 2000, 2002, 2003, 2004, |
| 4 | ;; 2005, 2006 Free Software Foundation, Inc. |
| 5 | |
| 6 | ;; Author: Daiki Ueno <ueno@unixuser.org> |
| 7 | ;; Symmetric encryption added by: Sascha Wilde <wilde@sha-bang.de> |
| 8 | ;; Created: 1999/10/28 |
| 9 | ;; Keywords: PGP, OpenPGP, GnuPG |
| 10 | |
| 11 | ;; This file is part of GNU Emacs. |
| 12 | |
| 13 | ;; GNU Emacs is free software; you can redistribute it and/or modify |
| 14 | ;; it under the terms of the GNU General Public License as published by |
| 15 | ;; the Free Software Foundation; either version 2, or (at your option) |
| 16 | ;; any later version. |
| 17 | |
| 18 | ;; GNU Emacs is distributed in the hope that it will be useful, |
| 19 | ;; but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 20 | ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 21 | ;; GNU General Public License for more details. |
| 22 | |
| 23 | ;; You should have received a copy of the GNU General Public License |
| 24 | ;; along with GNU Emacs; see the file COPYING. If not, write to the |
| 25 | ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| 26 | ;; Boston, MA 02110-1301, USA. |
| 27 | |
| 28 | ;;; Code: |
| 29 | |
| 30 | (eval-when-compile |
| 31 | (require 'cl) ; for gpg macros |
| 32 | (require 'pgg)) |
| 33 | |
| 34 | (defgroup pgg-gpg () |
| 35 | "GnuPG interface." |
| 36 | :group 'pgg) |
| 37 | |
| 38 | (defcustom pgg-gpg-program "gpg" |
| 39 | "The GnuPG executable." |
| 40 | :group 'pgg-gpg |
| 41 | :type 'string) |
| 42 | |
| 43 | (defcustom pgg-gpg-extra-args nil |
| 44 | "Extra arguments for every GnuPG invocation." |
| 45 | :group 'pgg-gpg |
| 46 | :type '(repeat (string :tag "Argument"))) |
| 47 | |
| 48 | (defcustom pgg-gpg-recipient-argument "--recipient" |
| 49 | "GnuPG option to specify recipient." |
| 50 | :group 'pgg-gpg |
| 51 | :type '(choice (const :tag "New `--recipient' option" "--recipient") |
| 52 | (const :tag "Old `--remote-user' option" "--remote-user"))) |
| 53 | |
| 54 | (defcustom pgg-gpg-use-agent (if (getenv "GPG_AGENT_INFO") t nil) |
| 55 | "Whether to use gnupg agent for key caching. |
| 56 | By default, it will be enabled iff the environment variable |
| 57 | \"GPG_AGENT_INFO\" is set." |
| 58 | :group 'pgg-gpg |
| 59 | :type 'boolean) |
| 60 | |
| 61 | (defvar pgg-gpg-user-id nil |
| 62 | "GnuPG ID of your default identity.") |
| 63 | |
| 64 | (defun pgg-gpg-process-region (start end passphrase program args) |
| 65 | (let* ((output-file-name (pgg-make-temp-file "pgg-output")) |
| 66 | (args |
| 67 | `("--status-fd" "2" |
| 68 | ,@(if pgg-gpg-use-agent '("--use-agent") |
| 69 | (if passphrase '("--passphrase-fd" "0"))) |
| 70 | "--yes" ; overwrite |
| 71 | "--output" ,output-file-name |
| 72 | ,@pgg-gpg-extra-args ,@args)) |
| 73 | (output-buffer pgg-output-buffer) |
| 74 | (errors-buffer pgg-errors-buffer) |
| 75 | (orig-mode (default-file-modes)) |
| 76 | (process-connection-type nil) |
| 77 | exit-status) |
| 78 | (with-current-buffer (get-buffer-create errors-buffer) |
| 79 | (buffer-disable-undo) |
| 80 | (erase-buffer)) |
| 81 | (unwind-protect |
| 82 | (progn |
| 83 | (set-default-file-modes 448) |
| 84 | (let ((coding-system-for-write 'binary) |
| 85 | (input (buffer-substring-no-properties start end)) |
| 86 | (default-enable-multibyte-characters nil)) |
| 87 | (with-temp-buffer |
| 88 | (when passphrase |
| 89 | (insert passphrase "\n")) |
| 90 | (insert input) |
| 91 | (setq exit-status |
| 92 | (apply #'call-process-region (point-min) (point-max) program |
| 93 | nil errors-buffer nil args)))) |
| 94 | (with-current-buffer (get-buffer-create output-buffer) |
| 95 | (buffer-disable-undo) |
| 96 | (erase-buffer) |
| 97 | (if (file-exists-p output-file-name) |
| 98 | (let ((coding-system-for-read (if pgg-text-mode |
| 99 | 'raw-text |
| 100 | 'binary))) |
| 101 | (insert-file-contents output-file-name))) |
| 102 | (set-buffer errors-buffer) |
| 103 | (if (not (equal exit-status 0)) |
| 104 | (insert (format "\n%s exited abnormally: '%s'\n" |
| 105 | program exit-status))))) |
| 106 | (if (file-exists-p output-file-name) |
| 107 | (delete-file output-file-name)) |
| 108 | (set-default-file-modes orig-mode)))) |
| 109 | |
| 110 | (defun pgg-gpg-possibly-cache-passphrase (passphrase &optional key notruncate) |
| 111 | (if (and passphrase |
| 112 | pgg-cache-passphrase |
| 113 | (progn |
| 114 | (goto-char (point-min)) |
| 115 | (re-search-forward "^\\[GNUPG:] \\(GOOD_PASSPHRASE\\>\\)\\|\\(SIG_CREATED\\)" nil t))) |
| 116 | (pgg-add-passphrase-to-cache |
| 117 | (or key |
| 118 | (progn |
| 119 | (goto-char (point-min)) |
| 120 | (if (re-search-forward |
| 121 | "^\\[GNUPG:] NEED_PASSPHRASE\\(_PIN\\)? \\w+ ?\\w*" nil t) |
| 122 | (substring (match-string 0) -8)))) |
| 123 | passphrase |
| 124 | notruncate))) |
| 125 | |
| 126 | (defvar pgg-gpg-all-secret-keys 'unknown) |
| 127 | |
| 128 | (defun pgg-gpg-lookup-all-secret-keys () |
| 129 | "Return all secret keys present in secret key ring." |
| 130 | (when (eq pgg-gpg-all-secret-keys 'unknown) |
| 131 | (setq pgg-gpg-all-secret-keys '()) |
| 132 | (let ((args (list "--with-colons" "--no-greeting" "--batch" |
| 133 | "--list-secret-keys"))) |
| 134 | (with-temp-buffer |
| 135 | (apply #'call-process pgg-gpg-program nil t nil args) |
| 136 | (goto-char (point-min)) |
| 137 | (while (re-search-forward |
| 138 | "^\\(sec\\|pub\\):[^:]*:[^:]*:[^:]*:\\([^:]*\\)" nil t) |
| 139 | (push (substring (match-string 2) 8) |
| 140 | pgg-gpg-all-secret-keys))))) |
| 141 | pgg-gpg-all-secret-keys) |
| 142 | |
| 143 | (defun pgg-gpg-lookup-key (string &optional type) |
| 144 | "Search keys associated with STRING." |
| 145 | (let ((args (list "--with-colons" "--no-greeting" "--batch" |
| 146 | (if type "--list-secret-keys" "--list-keys") |
| 147 | string))) |
| 148 | (with-temp-buffer |
| 149 | (apply #'call-process pgg-gpg-program nil t nil args) |
| 150 | (goto-char (point-min)) |
| 151 | (if (re-search-forward "^\\(sec\\|pub\\):[^:]*:[^:]*:[^:]*:\\([^:]*\\)" |
| 152 | nil t) |
| 153 | (substring (match-string 2) 8))))) |
| 154 | |
| 155 | (defun pgg-gpg-lookup-key-owner (string &optional all) |
| 156 | "Search keys associated with STRING and return owner of identified key. |
| 157 | |
| 158 | The value may be just the bare key id, or it may be a combination of the |
| 159 | user name associated with the key and the key id, with the key id enclosed |
| 160 | in \"<...>\" angle brackets. |
| 161 | |
| 162 | Optional ALL non-nil means search all keys, including secret keys." |
| 163 | (let ((args (list "--with-colons" "--no-greeting" "--batch" |
| 164 | (if all "--list-secret-keys" "--list-keys") |
| 165 | string)) |
| 166 | (key-regexp (concat "^\\(sec\\|pub\\)" |
| 167 | ":[^:]*:[^:]*:[^:]*:\\([^:]*\\):[^:]*" |
| 168 | ":[^:]*:[^:]*:[^:]*:\\([^:]*\\):"))) |
| 169 | (with-temp-buffer |
| 170 | (apply #'call-process pgg-gpg-program nil t nil args) |
| 171 | (goto-char (point-min)) |
| 172 | (if (re-search-forward key-regexp |
| 173 | nil t) |
| 174 | (match-string 3))))) |
| 175 | |
| 176 | (defun pgg-gpg-key-id-from-key-owner (key-owner) |
| 177 | (cond ((not key-owner) nil) |
| 178 | ;; Extract bare key id from outermost paired angle brackets, if any: |
| 179 | ((string-match "[^<]*<\\(.+\\)>[^>]*" key-owner) |
| 180 | (substring key-owner (match-beginning 1)(match-end 1))) |
| 181 | (key-owner))) |
| 182 | |
| 183 | (defun pgg-gpg-encrypt-region (start end recipients &optional sign passphrase) |
| 184 | "Encrypt the current region between START and END. |
| 185 | |
| 186 | If optional argument SIGN is non-nil, do a combined sign and encrypt. |
| 187 | |
| 188 | If optional PASSPHRASE is not specified, it will be obtained from the |
| 189 | passphrase cache or user." |
| 190 | (let* ((pgg-gpg-user-id (or pgg-gpg-user-id pgg-default-user-id)) |
| 191 | (passphrase (or passphrase |
| 192 | (when (and sign (not pgg-gpg-use-agent)) |
| 193 | (pgg-read-passphrase |
| 194 | (format "GnuPG passphrase for %s: " |
| 195 | pgg-gpg-user-id) |
| 196 | pgg-gpg-user-id)))) |
| 197 | (args |
| 198 | (append |
| 199 | (list "--batch" "--armor" "--always-trust" "--encrypt") |
| 200 | (if pgg-text-mode (list "--textmode")) |
| 201 | (if sign (list "--sign" "--local-user" pgg-gpg-user-id)) |
| 202 | (if recipients |
| 203 | (apply #'nconc |
| 204 | (mapcar (lambda (rcpt) |
| 205 | (list pgg-gpg-recipient-argument rcpt)) |
| 206 | (append recipients |
| 207 | (if pgg-encrypt-for-me |
| 208 | (list pgg-gpg-user-id))))))))) |
| 209 | (pgg-gpg-process-region start end passphrase pgg-gpg-program args) |
| 210 | (when sign |
| 211 | (with-current-buffer pgg-errors-buffer |
| 212 | ;; Possibly cache passphrase under, e.g. "jas", for future sign. |
| 213 | (pgg-gpg-possibly-cache-passphrase passphrase pgg-gpg-user-id) |
| 214 | ;; Possibly cache passphrase under, e.g. B565716F, for future decrypt. |
| 215 | (pgg-gpg-possibly-cache-passphrase passphrase))) |
| 216 | (pgg-process-when-success))) |
| 217 | |
| 218 | (defun pgg-gpg-encrypt-symmetric-region (start end &optional passphrase) |
| 219 | "Encrypt the current region between START and END with symmetric cipher. |
| 220 | |
| 221 | If optional PASSPHRASE is not specified, it will be obtained from the |
| 222 | passphrase cache or user." |
| 223 | (let* ((passphrase (or passphrase |
| 224 | (when (not pgg-gpg-use-agent) |
| 225 | (pgg-read-passphrase |
| 226 | "GnuPG passphrase for symmetric encryption: ")))) |
| 227 | (args |
| 228 | (append (list "--batch" "--armor" "--symmetric" ) |
| 229 | (if pgg-text-mode (list "--textmode"))))) |
| 230 | (pgg-gpg-process-region start end passphrase pgg-gpg-program args) |
| 231 | (pgg-process-when-success))) |
| 232 | |
| 233 | (defun pgg-gpg-decrypt-region (start end &optional passphrase) |
| 234 | "Decrypt the current region between START and END. |
| 235 | |
| 236 | If optional PASSPHRASE is not specified, it will be obtained from the |
| 237 | passphrase cache or user." |
| 238 | (let* ((current-buffer (current-buffer)) |
| 239 | (message-keys (with-temp-buffer |
| 240 | (insert-buffer-substring current-buffer) |
| 241 | (pgg-decode-armor-region (point-min) (point-max)))) |
| 242 | (secret-keys (pgg-gpg-lookup-all-secret-keys)) |
| 243 | ;; XXX the user is stuck if they need to use the passphrase for |
| 244 | ;; any but the first secret key for which the message is |
| 245 | ;; encrypted. ideally, we would incrementally give them a |
| 246 | ;; chance with subsequent keys each time they fail with one. |
| 247 | (key (pgg-gpg-select-matching-key message-keys secret-keys)) |
| 248 | (key-owner (and key (pgg-gpg-lookup-key-owner key t))) |
| 249 | (key-id (pgg-gpg-key-id-from-key-owner key-owner)) |
| 250 | (pgg-gpg-user-id (or key-id key |
| 251 | pgg-gpg-user-id pgg-default-user-id)) |
| 252 | (passphrase (or passphrase |
| 253 | (when (not pgg-gpg-use-agent) |
| 254 | (pgg-read-passphrase |
| 255 | (format (if (pgg-gpg-symmetric-key-p message-keys) |
| 256 | "Passphrase for symmetric decryption: " |
| 257 | "GnuPG passphrase for %s: ") |
| 258 | (or key-owner "??")) |
| 259 | pgg-gpg-user-id)))) |
| 260 | (args '("--batch" "--decrypt"))) |
| 261 | (pgg-gpg-process-region start end passphrase pgg-gpg-program args) |
| 262 | (with-current-buffer pgg-errors-buffer |
| 263 | (pgg-gpg-possibly-cache-passphrase passphrase pgg-gpg-user-id) |
| 264 | (goto-char (point-min)) |
| 265 | (re-search-forward "^\\[GNUPG:] DECRYPTION_OKAY\\>" nil t)))) |
| 266 | |
| 267 | ;;;###autoload |
| 268 | (defun pgg-gpg-symmetric-key-p (message-keys) |
| 269 | "True if decoded armor MESSAGE-KEYS has symmetric encryption indicator." |
| 270 | (let (result) |
| 271 | (dolist (key message-keys result) |
| 272 | (when (and (eq (car key) 3) |
| 273 | (member '(symmetric-key-algorithm) key)) |
| 274 | (setq result key))))) |
| 275 | |
| 276 | (defun pgg-gpg-select-matching-key (message-keys secret-keys) |
| 277 | "Choose a key from MESSAGE-KEYS that matches one of the keys in SECRET-KEYS." |
| 278 | (loop for message-key in message-keys |
| 279 | for message-key-id = (and (equal (car message-key) 1) |
| 280 | (cdr (assq 'key-identifier |
| 281 | (cdr message-key)))) |
| 282 | for key = (and message-key-id (pgg-lookup-key message-key-id 'encrypt)) |
| 283 | when (and key (member key secret-keys)) return key)) |
| 284 | |
| 285 | (defun pgg-gpg-sign-region (start end &optional cleartext passphrase) |
| 286 | "Make detached signature from text between START and END." |
| 287 | (let* ((pgg-gpg-user-id (or pgg-gpg-user-id pgg-default-user-id)) |
| 288 | (passphrase (or passphrase |
| 289 | (when (not pgg-gpg-use-agent) |
| 290 | (pgg-read-passphrase |
| 291 | (format "GnuPG passphrase for %s: " |
| 292 | pgg-gpg-user-id) |
| 293 | pgg-gpg-user-id)))) |
| 294 | (args |
| 295 | (append (list (if cleartext "--clearsign" "--detach-sign") |
| 296 | "--armor" "--batch" "--verbose" |
| 297 | "--local-user" pgg-gpg-user-id) |
| 298 | (if pgg-text-mode (list "--textmode")))) |
| 299 | (inhibit-read-only t) |
| 300 | buffer-read-only) |
| 301 | (pgg-gpg-process-region start end passphrase pgg-gpg-program args) |
| 302 | (with-current-buffer pgg-errors-buffer |
| 303 | ;; Possibly cache passphrase under, e.g. "jas", for future sign. |
| 304 | (pgg-gpg-possibly-cache-passphrase passphrase pgg-gpg-user-id) |
| 305 | ;; Possibly cache passphrase under, e.g. B565716F, for future decrypt. |
| 306 | (pgg-gpg-possibly-cache-passphrase passphrase)) |
| 307 | (pgg-process-when-success))) |
| 308 | |
| 309 | (defun pgg-gpg-verify-region (start end &optional signature) |
| 310 | "Verify region between START and END as the detached signature SIGNATURE." |
| 311 | (let ((args '("--batch" "--verify"))) |
| 312 | (when (stringp signature) |
| 313 | (setq args (append args (list signature)))) |
| 314 | (setq args (append args '("-"))) |
| 315 | (pgg-gpg-process-region start end nil pgg-gpg-program args) |
| 316 | (with-current-buffer pgg-errors-buffer |
| 317 | (goto-char (point-min)) |
| 318 | (while (re-search-forward "^gpg: \\(.*\\)\n" nil t) |
| 319 | (with-current-buffer pgg-output-buffer |
| 320 | (insert-buffer-substring pgg-errors-buffer |
| 321 | (match-beginning 1) (match-end 0))) |
| 322 | (delete-region (match-beginning 0) (match-end 0))) |
| 323 | (goto-char (point-min)) |
| 324 | (re-search-forward "^\\[GNUPG:] GOODSIG\\>" nil t)))) |
| 325 | |
| 326 | (defun pgg-gpg-insert-key () |
| 327 | "Insert public key at point." |
| 328 | (let* ((pgg-gpg-user-id (or pgg-gpg-user-id pgg-default-user-id)) |
| 329 | (args (list "--batch" "--export" "--armor" |
| 330 | pgg-gpg-user-id))) |
| 331 | (pgg-gpg-process-region (point)(point) nil pgg-gpg-program args) |
| 332 | (insert-buffer-substring pgg-output-buffer))) |
| 333 | |
| 334 | (defun pgg-gpg-snarf-keys-region (start end) |
| 335 | "Add all public keys in region between START and END to the keyring." |
| 336 | (let ((args '("--import" "--batch" "-")) status) |
| 337 | (pgg-gpg-process-region start end nil pgg-gpg-program args) |
| 338 | (set-buffer pgg-errors-buffer) |
| 339 | (goto-char (point-min)) |
| 340 | (when (re-search-forward "^\\[GNUPG:] IMPORT_RES\\>" nil t) |
| 341 | (setq status (buffer-substring (match-end 0) |
| 342 | (progn (end-of-line)(point))) |
| 343 | status (vconcat (mapcar #'string-to-number (split-string status)))) |
| 344 | (erase-buffer) |
| 345 | (insert (format "Imported %d key(s). |
| 346 | \tArmor contains %d key(s) [%d bad, %d old].\n" |
| 347 | (+ (aref status 2) |
| 348 | (aref status 10)) |
| 349 | (aref status 0) |
| 350 | (aref status 1) |
| 351 | (+ (aref status 4) |
| 352 | (aref status 11))) |
| 353 | (if (zerop (aref status 9)) |
| 354 | "" |
| 355 | "\tSecret keys are imported.\n"))) |
| 356 | (append-to-buffer pgg-output-buffer (point-min)(point-max)) |
| 357 | (pgg-process-when-success))) |
| 358 | |
| 359 | (provide 'pgg-gpg) |
| 360 | |
| 361 | ;;; arch-tag: 2aa5d5d8-93a0-4865-9312-33e29830e000 |
| 362 | ;;; pgg-gpg.el ends here |