1 ;;; gpg.el --- Interface to GNU Privacy Guard
3 ;; Copyright (C) 2000 RUS-CERT, University Of Stuttgart
5 ;; Author: Florian Weimer <Florian.Weimer@RUS.Uni-Stuttgart.DE>
6 ;; Maintainer: Florian Weimer <Florian.Weimer@RUS.Uni-Stuttgart.DE>
10 ;; $Id: gpg.el,v 1.4 2000/12/01 04:01:39 zsh Exp $
12 ;; This file is NOT (yet?) part of GNU Emacs.
14 ;; GNU Emacs is free software; you can redistribute it and/or modify
15 ;; it under the terms of the GNU General Public License as published by
16 ;; the Free Software Foundation; either version 2, or (at your option)
19 ;; GNU Emacs is distributed in the hope that it will be useful,
20 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
21 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 ;; GNU General Public License for more details.
24 ;; You should have received a copy of the GNU General Public License
25 ;; along with GNU Emacs; see the file COPYING. If not, write to the
26 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
27 ;; Boston, MA 02111-1307, USA.
31 ;; ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA
32 ;; ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA
34 ;; This code is not well-tested. BE CAREFUL!
36 ;; ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA
37 ;; ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA ALPHA
39 ;; Implemented features which can be tested:
41 ;; * Customization for all flavors of PGP is possible.
42 ;; * The main operations (verify, decrypt, sign, encrypt, sign &
43 ;; encrypt) are implemented.
44 ;; * Gero Treuner's gpg-2comp script is supported, and data which is is
45 ;; compatible with PGP 2.6.3 is generated.
47 ;; Customizing external programs
48 ;; =============================
50 ;; The customization are very similar to those of others programs,
51 ;; only the C-ish "%" constructs have been replaced by more Lisp-like
54 ;; First, you have to adjust the default executable paths
55 ;; (`gpg-command-default-alist', customization group `gpg-options',
56 ;; "Controlling GnuPG invocation."). After that, you should
57 ;; change the configuration options which control how specific
58 ;; command line flags are built (`gpg-command-flag-sign-with-key',
59 ;; (`gpg-command-flag-recipient'). The elements of these lists are
60 ;; concatenated without spaces, and a new argument is only started
61 ;; where indicated. The `gpg-command-flag-recipient' list is special:
62 ;; it consists of two parts, the first one remains at the beginning
63 ;; of the argument, the second one is repeated for each recipient.
64 ;; Finally, `gpg-command-passphrase-env' has to be changed if there's
65 ;; no command line flag to force the external program to read the data
66 ;; from standard input before the message.
68 ;; In customization group `gpg-commands', "Controlling GnuPG
69 ;; invocation.", you have to supply the actual syntax for external
70 ;; program calls. Each variable consists of a pair of a program
71 ;; specification (if a Lisp symbol is given here, it is translated
72 ;; via `gpg-command-default-alist') and a list of program arguments
73 ;; with placeholders. Please read the documentation of each variable
74 ;; before making your adjustments and try to match the given
75 ;; requirements as closely as possible!
77 ;; The `gpg-commands-key' group, "GnuPG Key Management Commands.",
78 ;; specifies key management commands. The syntax of these variables
79 ;; is like those in the `gpg-commands' group. Note that the output
80 ;; format of some of these external programs has to match very close
81 ;; that of GnuPG. Additional tools (Thomas Roessler's "pgpring.c")
82 ;; are available if your favorite implementation of OpenPGP cannot
83 ;; output the this format.
85 ;; Security considerations
86 ;; =======================
88 ;; On a typical multiuser UNIX system, the memory image of the
89 ;; Emacs process is not locked, therefore it can be swapped to disk
90 ;; at any time. As a result, the passphrase might show up in the
91 ;; swap space (even if you don't use the passphrase cache, i.e. if
92 ;; `gpg-passphrase-timeout' is 0). If someone is able to run `gdb' or
93 ;; another debugger on your Emacs process, he might be able to recover
94 ;; the passphrase as well. Unfortunately, nothing can be done in
95 ;; order to prevent this at the moment.
97 ;; BE CAREFUL: If you use the passphrase cache feature, the passphrase
98 ;; is stored in the variable `gpg-passphrase' -- and it is NOT
99 ;; encrypted in any way. (This is a conceptual problem because the
100 ;; nature of the passphrase cache requires that Emacs is able to
101 ;; decrypt automatically, so only a very weak protection could be
104 ;; In addition, if you use an unpatched Emacs 20 (and earlier
105 ;; versions), passwords show up in the output of the `view-lossage'
106 ;; function (bound to `C-h l' by default).
115 (defalias 'gpg-point-at-eol
116 (if (fboundp 'point-at-eol)
122 ;;; Customization: Groups:
125 "GNU Privacy Guard interface."
129 (defgroup gpg-options nil
130 "Controlling GnuPG invocation."
134 (defgroup gpg-commands nil
135 "Primary GnuPG Operations."
136 :tag "GnuPG Commands"
139 (defgroup gpg-commands-key nil
140 "Commands for GnuPG key management."
141 :tag "GnuPG Key Commands"
142 :group 'gpg-commands)
144 ;;; Customization: Widgets:
146 (define-widget 'gpg-command-alist 'alist
147 "An association list for GnuPG command names."
148 :key-type '(symbol :tag "Abbreviation")
149 :value-type '(string :tag "Program name")
150 :convert-widget 'widget-alist-convert-widget
153 (define-widget 'gpg-command-program 'choice
154 "Widget for entering the name of a program (mostly the GnuPG binary)."
156 :args '((const :tag "Default GnuPG program."
158 (const :tag "GnuPG compatibility wrapper."
160 (const :tag "Disabled"
162 (string :tag "Custom program" :format "%v")))
164 (define-widget 'gpg-command-sign-options 'cons
165 "Widget for entering signing options."
166 :args '(gpg-command-program
170 :format "%[Type%] %v"
171 (const :tag "Insert armor option here if necessary."
173 (const :tag "Insert text mode option here if necessary."
175 (const :tag "Insert the sign with key option here if necessary."
176 :value sign-with-key)
177 (string :format "%v")))))
179 (define-widget 'gpg-command-key-options 'cons
180 "Widget for entering key command options."
181 :args '(gpg-command-program
185 :format "%[Type%] %v"
186 (const :tag "Insert key ID here."
188 (string :format "%v")))))
190 ;;; Customization: Variables:
192 ;;; Customization: Variables: Paths and Flags:
194 (defcustom gpg-passphrase-timeout
196 "Timeout (in seconds) for the passphrase cache.
197 The passphrase cache is cleared after is hasn't been used for this
198 many seconds. The values 0 means that the passphrase is not cached at
200 :tag "Passphrase Timeout"
204 (defcustom gpg-default-key-id
206 "Default key/user ID used for signatures."
207 :tag "Default Key ID"
209 (const :tag "Use GnuPG default." :value nil)
213 (defcustom gpg-temp-directory
214 (expand-file-name "~/tmp")
215 "Directory for temporary files.
216 If you are running Emacs 20, this directory must have mode 0700."
217 :tag "Temp directory"
221 (defcustom gpg-command-default-alist
223 (gpg-2comp . "gpg-2comp"))
224 "Default paths for some GnuPG-related programs.
225 Modify this variable if you have to change the paths to the
226 executables required by the GnuPG interface. You can enter \"gpg\"
227 for `gpg-2comp' if you don't have this script, but you'll lose PGP
228 2.6.x compatibility."
229 :tag "GnuPG programs"
230 :type 'gpg-command-alist
233 (defcustom gpg-command-flag-textmode "--textmode"
234 "The flag to indicate canonical text mode to GnuPG."
235 :tag "Text mode flag"
239 (defcustom gpg-command-flag-armor "--armor"
240 "The flag to request ASCII-armoring output from GnuPG."
245 (defcustom gpg-command-flag-sign-with-key '("--local-user=" sign-with-key)
246 "String to include to specify the signing key ID.
247 The elements are concatenated (without spaces) to form a command line
249 :tag "Sign with key flag"
250 :type '(repeat :tag "Argument parts"
251 (choice :format "%[Type%] %v"
252 (const :tag "Start next argument." :value next-argument)
253 (const :tag "Insert signing key ID here." :value sign-with-key)
257 (defcustom gpg-command-flag-recipient
258 '(nil . ("-r" next-argument recipient next-argument))
259 "Format of a recipient specification.
260 The elements are concatenated (without spaces) to form a command line
261 option. The second part is repeated for each recipient."
262 :tag "Recipients Flag"
264 (repeat :tag "Common prefix"
265 (choice :format "%[Type%] %v"
266 (const :tag "Start next argument." :value next-argument)
268 (repeat :tag "For each recipient"
269 (choice :format "%[Type%] %v"
270 (const :tag "Start next argument." :value next-argument)
271 (const :tag "Insert recipient key ID here." :value recipient)
275 (defcustom gpg-command-passphrase-env
277 "Environment variable to set when a passphrase is required, or nil.
278 If an operation is invoked which requires a passphrase, this
279 environment variable is set before calling the external program to
280 indicate that it should read the passphrase from standard input."
281 :tag "Passphrase environment"
283 (const :tag "Disabled" :value nil)
285 (string :tag "Variable")
286 (string :tag "Value")))
289 ;;; Customization: Variables: GnuPG Commands:
291 (defcustom gpg-command-verify
292 '(gpg . ("--batch" "--verbose" "--verify" signature-file message-file))
293 "Command to verify a detached signature.
294 The invoked program has to read the signed message and the signature
295 from the given files. It should write human-readable information to
296 standard output and/or standard error. The program shall not convert
297 charsets or line endings; the input data shall be treated as binary."
298 :tag "Verify Command"
304 :format "%[Type%] %v"
305 (const :tag "Insert name of file containing the message here."
307 (const :tag "Insert name of file containing the signature here."
308 :value signature-file)
309 (string :format "%v"))))
310 :group 'gpg-commands)
312 (defcustom gpg-command-verify-cleartext
313 '(gpg . ("--batch" "--verbose" "--verify" message-file))
314 "Command to verify a message.
315 The invoked program has to read the signed message from the given
316 file. It should write human-readable information to standard output
317 and/or standard error. The program shall not convert charsets or line
318 endings; the input data shall be treated as binary."
319 :tag "Cleartext Verify Command"
325 :format "%[Type%] %v"
326 (const :tag "Insert name of file containing the message here."
328 (string :format "%v"))))
329 :group 'gpg-commands)
331 (defcustom gpg-command-decrypt
332 '(gpg . ("--decrypt" "--batch" "--passphrase-fd=0"))
333 "Command to decrypt a message.
334 The invoked program has to read the passphrase from standard
335 input, followed by the encrypted message. It writes the decrypted
336 message to standard output, and human-readable diagnostic messages to
338 :tag "Decrypt Command"
344 :format "%[Type%] %v"
345 (const :tag "Insert name of file containing the message here."
347 (string :format "%v"))))
348 :group 'gpg-commands)
350 (defcustom gpg-command-sign-cleartext
351 '(gpg-2comp . ("--batch" "--passphrase-fd=0" "--output=-"
352 armor textmode "--clearsign"
354 "Command to create a create a \"clearsign\" text file.
355 The invoked program has to read the passphrase from standard input,
356 followed by the message to sign. It should write the ASCII-amored
357 signed text message to standard output, and diagnostic messages to
359 :tag "Clearsign Command"
360 :type 'gpg-command-sign-options
361 :group 'gpg-commands)
363 (defcustom gpg-command-sign-detached
364 '(gpg-2comp . ("--batch" "--passphrase-fd=0" "--output=-"
365 armor textmode "--detach-sign"
367 "Command to create a create a detached signature.
368 The invoked program has to read the passphrase from standard input,
369 followed by the message to sign. It should write the ASCII-amored
370 detached signature to standard output, and diagnostic messages to
371 standard error. The program shall not convert charsets or line
372 endings; the input data shall be treated as binary."
373 :tag "Sign Detached Command"
374 :type 'gpg-command-sign-options
375 :group 'gpg-commands)
377 (defcustom gpg-command-sign-encrypt
378 '(gpg-2comp . ("--batch" "--passphrase-fd=0" "--output=-"
379 armor textmode "--always-trust" sign-with-key recipients
380 "--sign" "--encrypt" plaintext-file))
381 "Command to sign and encrypt a file.
382 The invoked program has to read the passphrase from standard input,
383 followed by the message to sign and encrypt if there is no
384 `plaintext-file' placeholder. It should write the ASCII-amored
385 encrypted message to standard output, and diagnostic messages to
387 :tag "Sign And Encrypt Command"
393 :format "%[Type%] %v"
394 (const :tag "Insert the `sign with key' option here if necessary."
395 :value sign-with-key)
396 (const :tag "Insert list of recipients here."
398 (const :tag "Insert here name of file with plaintext."
399 :value plaintext-file)
400 (string :format "%v"))))
401 :group 'gpg-commands)
403 (defcustom gpg-command-encrypt
404 '(gpg-2comp . ("--batch" "--output=-" armor textmode "--always-trust"
405 "--encrypt" recipients plaintext-file))
406 "Command to encrypt a file.
407 The invoked program has to read the message to encrypt from standard
408 input or from the plaintext file (if the `plaintext-file' placeholder
409 is present). It should write the ASCII-amored encrypted message to
410 standard output, and diagnostic messages to standard error."
416 :format "%[Type%] %v"
417 (const :tag "Insert list of recipients here."
419 (const :tag "Insert here name of file with plaintext."
420 :value plaintext-file)
421 (string :format "%v"))))
422 :group 'gpg-commands)
424 ;;; Customization: Variables: Key Management Commands:
426 (defcustom gpg-command-key-import
427 '(gpg . ("--import" "--verbose" message-file))
428 "Command to import a public key from a file."
429 :tag "Import Command"
435 :format "%[Type%] %v"
436 (const :tag "Insert name of file containing the key here."
438 (string :format "%v"))))
439 :group 'gpg-commands-key)
441 (defcustom gpg-command-key-export
442 '(gpg . ("--no-verbose" "--armor" "--export" key-id))
443 "Command to export a public key from the key ring.
444 The key should be written to standard output using ASCII armor."
445 :tag "Export Command"
446 :type 'gpg-command-key-options
447 :group 'gpg-commands-key)
449 (defcustom gpg-command-key-verify
450 '(gpg . ("--no-verbose" "--batch" "--fingerprint" "--check-sigs" key-id))
451 "Command to verify a public key."
452 :tag "Verification Command"
453 :type 'gpg-command-key-options
454 :group 'gpg-commands-key)
456 (defcustom gpg-command-key-public-ring
457 '(gpg . ("--no-verbose" "--batch" "--with-colons" "--list-keys" key-id))
458 "Command to list the contents of the public key ring."
459 :tag "List Public Key Ring Command"
460 :type 'gpg-command-key-options
461 :group 'gpg-commands-key)
463 (defcustom gpg-command-key-secret-ring
464 '(gpg . ("--no-verbose" "--batch" "--with-colons"
465 "--list-secret-keys" key-id))
466 "Command to list the contents of the secret key ring."
467 :tag "List Secret Key Ring Command"
468 :type 'gpg-command-key-options
469 :group 'gpg-commands-key)
471 (defcustom gpg-command-key-retrieve
472 '(gpg . ("--batch" "--recv-keys" key-id))
473 "Command to retrieve public keys."
474 :tag "Retrieve Keys Command"
475 :type 'gpg-command-key-options
476 :group 'gpg-commands-key)
479 ;;;; Helper functions for GnuPG invocation:
481 ;;; Build the GnuPG command line:
483 (defun gpg-build-argument (template substitutions &optional pass-start)
484 "Build command line argument(s) by substituting placeholders.
485 TEMPLATE is a list of strings and symbols. The placeholder symbols in
486 it are replaced by SUBSTITUTIONS, the elements between
487 `next-argument' symbols are concatenated without spaces and are
490 SUBSTITIONS is a list of (SYMBOL . SEXP) pairs, where SEXP is either
491 a string (which is inserted literally), a list of strings (which are
492 inserted as well), or nil, which means to insert nothing.
494 If PASS-START is t, `next-argument' is also inserted into the result,
495 and symbols without a proper substitution are retained in the output,
496 otherwise, an untranslated symbol results in an error.
498 This function does not handle empty arguments reliably."
499 (let ((current-arg "")
502 (let* ((templ (pop template))
503 (repl (assoc templ substitutions))
504 (new (if repl (cdr repl) templ)))
506 ((eq templ 'next-argument)
507 ;; If the current argument is not empty, start a new one.
508 (unless (equal current-arg "")
509 (setq arglist (nconc arglist
511 (list current-arg 'next-argument)
512 (list current-arg))))
513 (setq current-arg "")))
514 ((null new) nil) ; Drop it.
515 ((and (not (stringp templ)) (null repl))
516 ;; Retain an untranslated symbol in the output if
517 ;; `pass-start' is true.
519 (error "No replacement for `%s'" templ))
520 (setq arglist (nconc arglist (list current-arg templ)))
521 (setq current-arg ""))
524 (setq new (list new)))
525 (setq current-arg (concat current-arg
526 (apply 'concat new)))))))
527 (unless (equal current-arg "")
528 (setq arglist (nconc arglist (list current-arg))))
531 (defun gpg-build-arg-list (template substitutions)
532 "Build command line by substituting placeholders.
533 TEMPLATE is a list of strings and symbols. The placeholder symbols in
534 it are replaced by SUBSTITUTIONS.
536 SUBSTITIONS is a list of (SYMBOL . SEXP) pairs, where SEXP is either a
537 string (which is inserted literally), a list of strings (which are
538 inserted as well), or nil, which means to insert nothing."
541 (let* ((templ (pop template))
542 (repl (assoc templ substitutions))
543 (new (if repl (cdr repl) templ)))
545 ((and (symbolp templ) (null repl))
546 (error "No replacement for `%s'" templ))
547 ((null new) nil) ; Drop it.
550 (setq new (list new)))
551 (setq arglist (nconc arglist new))))))
554 (defun gpg-build-flag-recipients-one (recipient)
555 "Build argument for one RECIPIENT."
556 (gpg-build-argument (cdr gpg-command-flag-recipient)
557 `((recipient . ,recipient)) t))
559 (defun gpg-build-flag-recipients (recipients)
560 "Build list of RECIPIENTS using `gpg-command-flag-recipient'."
562 (apply 'append (car gpg-command-flag-recipient)
563 (mapcar 'gpg-build-flag-recipients-one
567 (defun gpg-read-recipients ()
568 "Query the user for several recipients."
572 (setq r (read-string "Enter recipient ID [RET when no more]: "))
575 (setq recipients (nconc recipients (list r)))))
578 (defun gpg-build-flag-sign-with-key (key)
579 "Build sign with key flag using `gpg-command-flag-sign-with-key'."
581 (if gpg-default-key-id gpg-default-key-id
584 (gpg-build-argument gpg-command-flag-sign-with-key
585 (list (cons 'sign-with-key k)))
588 (defmacro gpg-with-passphrase-env (&rest body)
589 "Adjust the process environment and evaluate BODY.
590 During the evaluation of the body forms, the process environment is
591 adjust according to `gpg-command-passphrase-env'."
592 (let ((env-value (make-symbol "env-value")))
596 (when gpg-command-passphrase-env
597 (setq ,env-value (getenv (car gpg-command-passphrase-env)))
598 (setenv (car gpg-command-passphrase-env)
599 (cdr gpg-command-passphrase-env)))
601 (when gpg-command-passphrase-env
602 ;; This will clear the variable if it wasn't set before.
603 (setenv (car gpg-command-passphrase-env) ,env-value))))))
604 (put 'gpg-with-passphrase-env 'lisp-indent-function 0)
605 (put 'gpg-with-passphrase-env 'edebug-form-spec '(body))
609 (defun gpg-make-temp-file ()
610 "Create a temporary file in a safe way"
611 (let ((name ;; User may use "~/"
612 (expand-file-name "gnupg" gpg-temp-directory)))
613 (if (fboundp 'make-temp-file)
614 ;; If we've got make-temp-file, we are on the save side.
615 (make-temp-file name)
616 ;; make-temp-name doesn't create the file, and an ordinary
617 ;; write-file operation is prone to nasty symlink attacks if the
618 ;; temporary file resides in a world-writable directory.
619 (unless (eq (file-modes gpg-temp-directory) 448) ; mode 0700
620 (error "Directory for temporary files must have mode 0700."))
621 (setq name (make-temp-name name))
622 (let ((mode (default-file-modes)))
625 (set-default-file-modes 384) ; mode 0600
626 (with-temp-file name))
627 (set-default-file-modes mode)))
630 (defvar gpg-temp-files nil
631 "List of temporary files used by the GnuPG interface.
632 Do not set this variable. Call `gpg-with-temp-files' if you need
635 (defun gpg-with-temp-files-create (count)
636 "Do not call this function. Used internally by `gpg-with-temp-files'."
638 (setq gpg-temp-files (cons (gpg-make-temp-file) gpg-temp-files))
639 (setq count (1- count))))
641 (defun gpg-with-temp-files-delete ()
642 "Do not call this function. Used internally by `gpg-with-temp-files'."
643 (while gpg-temp-files
644 (let ((file (pop gpg-temp-files)))
649 (defmacro gpg-with-temp-files (count &rest body)
650 "Create COUNT temporary files, USE them, and delete them.
651 The function USE is called with the names of all temporary files as
653 `(let ((gpg-temp-files))
656 ;; Create the temporary files.
657 (gpg-with-temp-files-create ,count)
659 (gpg-with-temp-files-delete))))
660 (put 'gpg-with-temp-files 'lisp-indent-function 1)
661 (put 'gpg-with-temp-files 'edebug-form-spec '(body))
663 ;;; Making subprocesses:
665 (defun gpg-exec-path (option)
666 "Return the program name for OPTION.
667 OPTION is of the form (PROGRAM . ARGLIST). This functions returns
668 PROGRAM, but takes default values into account."
669 (let* ((prg (car option))
670 (path (assq prg gpg-command-default-alist)))
672 (path (if (null (cdr path))
673 (error "Command `%s' is not available" prg)
675 ((null prg) (error "Command is disabled"))
678 (defun gpg-call-process (cmd args stdin stdout stderr &optional passphrase)
679 "Invoke external program CMD with ARGS on buffer STDIN.
680 Standard output is insert before point in STDOUT, standard error in
681 STDERR. If PASSPHRASE is given, send it before STDIN. PASSPHRASE
682 should not end with a line feed (\"\\n\").
684 If `stdin-file' is present in ARGS, it is replaced by the name of a
685 temporary file. Before invoking CMD, the contents of STDIN is written
687 (gpg-with-temp-files 2
688 (let* ((coding-system-for-read 'no-conversion)
689 (coding-system-for-write 'no-conversion)
690 (have-stdin-file (memq 'stdin-file args))
691 (stdin-file (nth 0 gpg-temp-files))
692 (stderr-file (nth 1 gpg-temp-files))
695 (,stdout ,stderr-file)
697 ;; Replace `stdin-file'.
698 ,@(gpg-build-arg-list
699 args (list (cons 'stdin-file stdin-file)))))
701 (when have-stdin-file
702 (with-temp-file stdin-file
703 (buffer-disable-undo)
704 (insert-buffer-substring stdin)))
708 (buffer-disable-undo)
709 (insert passphrase "\n")
710 (unless have-stdin-file
711 (apply 'insert-buffer-substring
712 (if (listp stdin) stdin (list stdin))))
713 (apply 'call-process-region (point-min) (point-max) cpr-args)
714 ;; Wipe out passphrase.
715 (goto-char (point-min))
716 (translate-region (point) (gpg-point-at-eol)
717 (make-string 256 ? )))
719 (with-current-buffer (car stdin)
720 (apply 'call-process-region
722 (if have-stdin-file (cadr stdin) (caddr stdin))
724 (with-current-buffer stdin
725 (apply 'call-process-region
727 (if have-stdin-file (point-min) (point-max))
729 (with-current-buffer stderr
730 (insert-file-contents-literally stderr-file))
731 (if (or (stringp res) (> res 0))
732 ;; Signal or abnormal exit.
733 (with-current-buffer stderr
734 (goto-char (point-max))
735 (insert (format "\nCommand exit status: %s\n" res))
739 (defvar gpg-result-buffer nil
740 "The result of a GnuPG operation is stored in this buffer.
741 Never set this variable directly, use `gpg-show-result' instead.")
743 (defun gpg-show-result-buffer (always-show result)
744 "Called by `gpg-show-results' to actually show the buffer."
745 (with-current-buffer gpg-result-buffer
746 ;; Only proceed if the buffer is non-empty.
747 (when (and (/= (point-min) (point-max))
748 (or always-show (not result)))
749 (save-window-excursion
750 (display-buffer (current-buffer))
751 (unless (y-or-n-p "Continue? ")
752 (error "GnuPG operation aborted."))))))
754 (defmacro gpg-show-result (always-show &rest body)
755 "Show GnuPG result to user for confirmation.
756 This macro binds `gpg-result-buffer' to a temporary buffer and
757 evaluates BODY, like `progn'. If BODY evaluates to `nil' (or
758 `always-show' is not nil), the user is asked for confirmation."
759 `(let ((gpg-result-buffer (get-buffer-create
760 (generate-new-buffer-name "*GnuPG Output*"))))
762 (gpg-show-result-buffer ,always-show (progn ,@body))
763 (kill-buffer gpg-result-buffer))))
764 (put 'gpg-show-result 'lisp-indent-function 1)
765 (put 'gpg-show-result 'edebug-form-spec '(body))
767 ;;; Passphrase handling:
769 (defvar gpg-passphrase-timer
771 "This timer will clear the passphrase cache periodically.")
773 (defvar gpg-passphrase
775 "The (unencrypted) passphrase cache.")
777 (defun gpg-passphrase-clear-string (str)
778 "Erases STR by overwriting all characters."
786 (defun gpg-passphrase-forget ()
787 "Forget stored passphrase."
789 (cancel-timer gpg-passphrase-timer)
790 (gpg-passphrase-clear-string gpg-passphrase)
791 (setq gpg-passphrase nil))
793 (defun gpg-passphrase-store (passphrase)
794 "Store PASSPHRASE in cache.
795 Updates the timeout for clearing the cache to `gpg-passphrase-timeout'."
796 (unless (equal gpg-passphrase-timeout 0)
797 (timer-set-time gpg-passphrase-timer
798 (timer-relative-time (current-time)
799 gpg-passphrase-timeout))
800 (timer-set-function gpg-passphrase-timer 'gpg-passphrase-forget)
801 (timer-activate gpg-passphrase-timer)
802 (setq gpg-passphrase passphrase))
805 (defun gpg-passphrase-read ()
806 "Read a passphrase and remember it for some time."
809 ;; This reinitializes the timer.
810 (gpg-passphrase-store gpg-passphrase)
811 (let ((pp (read-passwd "Enter passphrase: ")))
812 (gpg-passphrase-store pp))))
815 ;;;; Main operations:
818 (defun gpg-verify (message signature result)
819 "Verify buffer MESSAGE against detached SIGNATURE buffer.
820 Returns t if everything worked out well, nil otherwise. Consult
821 buffer RESULT for details."
822 (interactive "bBuffer containing message: \nbBuffer containing signature: \nbBuffor for result: ")
823 (gpg-with-temp-files 2
824 (let* ((sig-file (nth 0 gpg-temp-files))
825 (msg-file (nth 1 gpg-temp-files))
826 (cmd (gpg-exec-path gpg-command-verify))
827 (args (gpg-build-arg-list (cdr gpg-command-verify)
828 `((signature-file . ,sig-file)
829 (message-file . ,msg-file))))
831 (with-temp-file sig-file
832 (buffer-disable-undo)
833 (apply 'insert-buffer-substring (if (listp signature)
836 (with-temp-file msg-file
837 (buffer-disable-undo)
838 (apply 'insert-buffer-substring (if (listp message)
841 (setq res (apply 'call-process-region
842 (point-min) (point-min) ; no data
848 (if (or (stringp res) (> res 0))
849 ;; Signal or abnormal exit.
850 (with-current-buffer result
851 (insert (format "\nCommand exit status: %s\n" res))
856 (defun gpg-verify-cleartext (message result)
857 "Verify message in buffer MESSAGE.
858 Returns t if everything worked out well, nil otherwise. Consult
859 buffer RESULT for details.
861 NOTE: Use of this function is deprecated."
862 (interactive "bBuffer containing message: \nbBuffor for result: ")
863 (gpg-with-temp-files 1
864 (let* ((msg-file (nth 0 gpg-temp-files))
865 (cmd (gpg-exec-path gpg-command-verify-cleartext))
866 (args (gpg-build-arg-list (cdr gpg-command-verify-cleartext)
867 `((message-file . ,msg-file))))
869 (with-temp-file msg-file
870 (buffer-disable-undo)
871 (apply 'insert-buffer-substring (if (listp message)
874 (setq res (apply 'call-process-region
875 (point-min) (point-min) ; no data
881 (if (or (stringp res) (> res 0))
882 ;; Signal or abnormal exit.
883 (with-current-buffer result
884 (insert (format "\nCommand exit status: %s\n" res))
889 (defun gpg-decrypt (ciphertext plaintext result &optional passphrase)
890 "Decrypt buffer CIPHERTEXT to buffer PLAINTEXT.
891 Returns t if everything worked out well, nil otherwise. Consult
892 buffer RESULT for details. Reads a missing PASSPHRASE using
893 `gpg-passphrase-read'."
894 (interactive "bBuffer containing ciphertext: \nbBuffer for plaintext: \nbBuffor for decryption status: ")
895 (gpg-call-process (gpg-exec-path gpg-command-decrypt)
896 (gpg-build-arg-list (cdr gpg-command-decrypt) nil)
897 ciphertext plaintext result
898 (if passphrase passphrase (gpg-passphrase-read)))
900 (gpg-passphrase-clear-string passphrase)))
903 (defun gpg-sign-cleartext
904 (plaintext signed-text result &optional passphrase sign-with-key)
905 "Sign buffer PLAINTEXT, and store PLAINTEXT with signature in
907 Reads a missing PASSPHRASE using `gpg-passphrase-read'. Uses key ID
908 SIGN-WITH-KEY if given, otherwise the default key ID. Returns t if
909 everything worked out well, nil otherwise. Consult buffer RESULT for
912 NOTE: Use of this function is deprecated."
913 (interactive "bBuffer containing plaintext: \nbBuffer for text with signature: \nbBuffer for status information: ")
914 (let ((subst (list (cons 'sign-with-key
915 (gpg-build-flag-sign-with-key sign-with-key))
916 (cons 'armor gpg-command-flag-armor)
917 (cons 'textmode gpg-command-flag-textmode))))
918 (gpg-call-process (gpg-exec-path gpg-command-sign-cleartext)
919 (gpg-build-arg-list (cdr gpg-command-sign-cleartext)
921 plaintext signed-text result
922 (if passphrase passphrase (gpg-passphrase-read))))
924 (gpg-passphrase-clear-string passphrase)))
927 (defun gpg-sign-detached
928 (plaintext signature result &optional passphrase sign-with-key
930 "Sign buffer PLAINTEXT, and store SIGNATURE in that buffer.
931 Reads a missing PASSPHRASE using `gpg-passphrase-read'. Uses key ID
932 SIGN-WITH-KEY if given, otherwise the default key ID. Returns t if
933 everything worked out well, nil otherwise. Consult buffer RESULT for
934 details. ARMOR the result and activate canonical TEXTMODE if
936 (interactive "bBuffer containing plaintext: \nbBuffer for text with signature: \nbBuffer for status information: ")
937 (let ((subst (list (cons 'sign-with-key
938 (gpg-build-flag-sign-with-key sign-with-key))
939 (cons 'armor (if armor gpg-command-flag-armor))
940 (cons 'textmode (if armor gpg-command-flag-textmode)))))
941 (gpg-call-process (gpg-exec-path gpg-command-sign-detached)
942 (gpg-build-arg-list (cdr gpg-command-sign-detached)
944 plaintext signature result
945 (if passphrase passphrase (gpg-passphrase-read))))
947 (gpg-passphrase-clear-string passphrase)))
951 (defun gpg-sign-encrypt
952 (plaintext ciphertext result recipients &optional passphrase sign-with-key
954 "Sign buffer PLAINTEXT, and store SIGNATURE in that buffer.
955 RECIPIENTS is a list of key IDs used for encryption. This function
956 reads a missing PASSPHRASE using `gpg-passphrase-read', and uses key
957 ID SIGN-WITH-KEY for the signature if given, otherwise the default key
958 ID. Returns t if everything worked out well, nil otherwise. Consult
959 buffer RESULT for details. ARMOR the result and activate canonical
960 TEXTMODE if requested."
962 (read-buffer "Buffer containing plaintext: " nil t)
963 (read-buffer "Buffer for ciphertext: " nil t)
964 (read-buffer "Buffer for status informationt: " nil t)
965 (gpg-read-recipients)))
966 (let ((subst `((sign-with-key . ,(gpg-build-flag-sign-with-key
968 (plaintext-file . stdin-file)
969 (recipients . ,(gpg-build-flag-recipients recipients))
970 (armor ,(if armor gpg-command-flag-armor))
971 (textmode ,(if armor gpg-command-flag-textmode)))))
972 (gpg-call-process (gpg-exec-path gpg-command-sign-encrypt)
973 (gpg-build-arg-list (cdr gpg-command-sign-encrypt)
975 plaintext ciphertext result
976 (if passphrase passphrase (gpg-passphrase-read))))
978 (gpg-passphrase-clear-string passphrase)))
983 (plaintext ciphertext result recipients &optional passphrase armor textmode)
984 "Encrypt buffer PLAINTEXT, and store CIPHERTEXT in that buffer.
985 RECIPIENTS is a list of key IDs used for encryption. Returns t if
986 everything worked out well, nil otherwise. Consult buffer RESULT for
987 details. ARMOR the result and activate canonical
988 TEXTMODE if requested."
990 (read-buffer "Buffer containing plaintext: " nil t)
991 (read-buffer "Buffer for ciphertext: " nil t)
992 (read-buffer "Buffer for status informationt: " nil t)
993 (gpg-read-recipients)))
994 (let ((subst `((plaintext-file . stdin-file)
995 (recipients . ,(gpg-build-flag-recipients recipients))
996 (armor ,(if armor gpg-command-flag-armor))
997 (textmode ,(if armor gpg-command-flag-textmode)))))
998 (gpg-call-process (gpg-exec-path gpg-command-encrypt)
999 (gpg-build-arg-list (cdr gpg-command-encrypt) subst)
1000 plaintext ciphertext result nil))
1002 (gpg-passphrase-clear-string passphrase)))
1007 ;;; ADT: OpenPGP Key
1009 (defun gpg-key-make (user-id key-id unique-id length algorithm
1010 creation-date expire-date validity trust)
1011 "Create a new key object (for internal use only)."
1014 user-id key-id unique-id length algorithm
1016 creation-date expire-date validity trust))
1019 (defun gpg-key-p (key)
1020 "Return t if KEY is a key specification."
1021 (and (arrayp key) (equal (length key) 9) key))
1023 (defmacro gpg-key-primary-user-id (key)
1024 "The primary user ID for KEY (human-readable).
1025 DO NOT USE this ID for selecting recipients. It is probably not
1027 (list 'car (list 'aref key 0)))
1029 (defmacro gpg-key-user-ids (key)
1030 "A list of additional user IDs for KEY (human-readable).
1031 DO NOT USE these IDs for selecting recipients. They are probably not
1033 (list 'cdr (list 'aref key 0)))
1035 (defmacro gpg-key-id (key)
1037 DO NOT USE this ID for selecting recipients. It is not guaranteed to
1041 (defun gpg-short-key-id (key)
1042 "The short key ID of KEY."
1043 (let* ((id (gpg-key-id key))
1046 (substring id (- len 8))
1049 (defmacro gpg-key-unique-id (key)
1050 "A non-standard ID of KEY which is only valid locally.
1051 This ID can be used to specify recipients in a safe manner. Note,
1052 even this ID might not be unique unless GnuPG is used."
1055 (defmacro gpg-key-unique-id-list (key-list)
1056 "Like `gpg-key-unique-id', but operate on a list."
1057 `(mapcar (lambda (key) (gpg-key-unique-id key))
1060 (defmacro gpg-key-length (key)
1061 "Returns the key length."
1064 (defmacro gpg-key-algorithm (key)
1065 "The encryption algorithm used by KEY.
1066 One of the symbols `rsa', `rsa-encrypt', `rsa-sign', `elgamal',
1067 `elgamal-encrypt', `dsa'."
1070 (defmacro gpg-key-creation-date (key)
1071 "A string with the creation date of KEY in ISO format."
1074 (defmacro gpg-key-expire-date (key)
1075 "A string with the expiration date of KEY in ISO format."
1078 (defmacro gpg-key-validity (key)
1079 "The calculated validity of KEY.
1080 One of the symbols `not-known', `disabled', `revoked', `expired',
1081 `undefined', `trust-none', `trust-marginal', `trust-full',
1082 `trust-ultimate' (see the GnuPG documentation for details)."
1085 (defmacro gpg-key-trust (key)
1086 "The assigned trust for KEY.
1087 One of the symbols `not-known', `undefined', `trust-none',
1088 `trust-marginal', `trust-full' (see the GnuPG
1089 documentation for details)."
1092 (defun gpg-key-lessp (a b)
1093 "Returns t if primary user ID of A is less than B."
1094 (string-lessp (gpg-key-primary-user-id a) (gpg-key-primary-user-id b) ))
1096 ;;; Accessing the key database:
1098 ;; Internal functions:
1100 (defmacro gpg-key-list-keys-skip-field ()
1101 '(search-forward ":" eol 'move))
1103 (defmacro gpg-key-list-keys-get-field ()
1104 '(buffer-substring (point) (if (gpg-key-list-keys-skip-field)
1107 (defmacro gpg-key-list-keys-string-field ()
1108 '(gpg-key-list-keys-get-field))
1110 (defmacro gpg-key-list-keys-read-field ()
1111 (let ((field (make-symbol "field")))
1112 `(let ((,field (gpg-key-list-keys-get-field)))
1113 (if (equal (length ,field) 0)
1117 (defun gpg-key-list-keys-parse-line ()
1118 "Parse the line in the current buffer and return a vector of fields."
1119 (let* ((eol (gpg-point-at-eol))
1123 (gpg-key-list-keys-read-field) ; type
1124 (gpg-key-list-keys-get-field) ; trust
1125 (gpg-key-list-keys-read-field) ; key length
1126 (gpg-key-list-keys-read-field) ; algorithm
1127 (gpg-key-list-keys-get-field) ; key ID
1128 (gpg-key-list-keys-get-field) ; creation data
1129 (gpg-key-list-keys-get-field) ; expire
1130 (gpg-key-list-keys-get-field) ; unique (local) ID
1131 (gpg-key-list-keys-get-field) ; ownertrust
1132 (gpg-key-list-keys-string-field) ; user ID
1137 (error "Too many fields in GnuPG key database"))
1140 (defconst gpg-pubkey-algo-alist
1142 (2 . rsa-encrypt-only)
1144 (16 . elgamal-encrypt-only)
1147 "Alist mapping OpenPGP public key algorithm numbers to symbols.")
1149 (defconst gpg-trust-alist
1155 (?q . trust-undefined)
1157 (?m . trust-marginal)
1159 (?u . trust-ultimate))
1160 "Alist mapping GnuPG trust value short forms to long symbols.")
1162 (defmacro gpg-key-list-keys-in-buffer-store ()
1163 '(when primary-user-id
1164 (sort user-id 'string-lessp)
1165 (push (gpg-key-make (cons primary-user-id user-id)
1166 key-id unique-id key-length
1167 algorithm creation-date
1168 expire-date validity trust)
1171 (defun gpg-key-list-keys-in-buffer (&optional buffer)
1172 "Return a list of keys for BUFFER.
1173 If BUFFER is omitted, use current buffer."
1174 (with-current-buffer (if buffer buffer (current-buffer))
1175 (goto-char (point-min))
1176 ;; Skip key ring filename written by GnuPG.
1177 (search-forward "\n---------------------------\n" nil t)
1178 ;; Loop over all lines in buffer and analyze them.
1179 (let (primary-user-id user-id key-id unique-id ; current key components
1180 key-length algorithm creation-date expire-date validity trust
1181 line ; fields in current line
1182 key-list) ; keys gather so far
1184 (while (setq line (gpg-key-list-keys-parse-line))
1186 ;; Public or secret key.
1187 ((memq (aref line 0) '(pub sec))
1188 ;; Store previous key, if any.
1189 (gpg-key-list-keys-in-buffer-store)
1190 ;; Record field values.
1191 (setq primary-user-id (aref line 9))
1193 (setq key-id (aref line 4))
1194 ;; We use the key ID if no unique ID is available.
1195 (setq unique-id (if (> (length (aref line 7)) 0)
1196 (concat "#" (aref line 7))
1197 (concat "0x" key-id)))
1198 (setq key-length (aref line 2))
1199 (setq algorithm (assq (aref line 3) gpg-pubkey-algo-alist))
1201 (setq algorithm (cdr algorithm))
1202 (error "Unknown algorithm %s" (aref line 3)))
1203 (setq creation-date (if (> (length (aref line 5)) 0)
1205 (setq expire-date (if (> (length (aref line 6)) 0)
1207 (setq validity (assq (aref (aref line 1) 0) gpg-trust-alist))
1209 (setq validity (cdr validity))
1210 (error "Unknown validity specification %S" (aref line 1)))
1211 (setq trust (assq (aref (aref line 8) 0) gpg-trust-alist))
1213 (setq trust (cdr trust))
1214 (error "Unknown trust specification %S" (aref line 8))))
1216 ;; Additional user ID
1217 ((eq 'uid (aref line 0))
1218 (setq user-id (cons (aref line 9) user-id)))
1220 ;; Subkeys are ignored for now.
1221 ((memq (aref line 0) '(sub ssb))
1223 (t (error "Unknown record type %S" (aref line 0)))))
1225 ;; Store the key retrieved last.
1226 (gpg-key-list-keys-in-buffer-store)
1227 ;; Sort the keys according to the primary user ID.
1228 (sort key-list 'gpg-key-lessp))))
1230 (defun gpg-key-list-keyspec (command &optional keyspec stderr ignore-error)
1231 "Insert the output of COMMAND before point in current buffer."
1232 (let* ((cmd (gpg-exec-path command))
1233 (key (if (equal keyspec "") nil keyspec))
1234 (args (gpg-build-arg-list (cdr command) `((key-id . ,key))))
1237 (apply 'call-process-region
1238 (point-min) (point-min) ; no data
1241 (if stderr t '(t nil))
1244 (unless (or ignore-error (equal exit-status 0))
1245 (error "GnuPG command exited unsuccessfully"))))
1248 (defun gpg-key-list-keyspec-parse (command &optional keyspec)
1249 "Return a list of keys matching KEYSPEC.
1250 COMMAND is used to obtain the key list. The usual substring search
1251 for keys is performed."
1253 (buffer-disable-undo)
1254 (gpg-key-list-keyspec command keyspec)
1255 (gpg-key-list-keys-in-buffer)))
1258 (defun gpg-key-list-keys (&optional keyspec)
1259 "A list of public keys matching KEYSPEC.
1260 The usual substring search for keys is performed."
1261 (gpg-key-list-keyspec-parse gpg-command-key-public-ring keyspec))
1264 (defun gpg-key-list-secret-keys (&optional keyspec)
1265 "A list of secret keys matching KEYSPEC.
1266 The usual substring search for keys is performed."
1267 (gpg-key-list-keyspec-parse gpg-command-key-secret-ring keyspec))
1270 (defun gpg-key-insert-public-key (key)
1271 "Inserts the public key(s) matching KEYSPEC.
1272 The ASCII-armored key is inserted before point into current buffer."
1273 (gpg-key-list-keyspec gpg-command-key-export key))
1276 (defun gpg-key-insert-information (key)
1277 "Insert human-readable information (including fingerprint) on KEY.
1278 Insertion takes place in current buffer before point."
1279 (gpg-key-list-keyspec gpg-command-key-verify key))
1282 (defun gpg-key-retrieve (key)
1283 "Fetch KEY from default key server.
1284 KEY is a key ID or a list of key IDs. Status information about this
1285 operation is inserted into the current buffer before point."
1286 (gpg-key-list-keyspec gpg-command-key-retrieve key t t))
1289 (defun gpg-key-add-to-ring (key result)
1290 "Adds key in buffer KEY to the GnuPG key ring.
1291 Human-readable information on the RESULT is stored in buffer RESULT
1296 ;;; gpg.el ends here