From 29b6f5569cb9bb89e8de238976bc99973dfe0164 Mon Sep 17 00:00:00 2001 From: ueno Date: Wed, 8 Dec 1999 09:32:28 +0000 Subject: [PATCH] * SEMI-ELS (semi-modules-to-compile): Add smime.el. * smime.el: New file. --- SEMI-ELS | 1 + smime.el | 314 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 315 insertions(+) create mode 100644 smime.el diff --git a/SEMI-ELS b/SEMI-ELS index 5f1e8c5..9e19169 100644 --- a/SEMI-ELS +++ b/SEMI-ELS @@ -7,6 +7,7 @@ (setq semi-modules-to-compile '(signature pgg-def pgg pgg-parse pgg-gpg pgg-pgp5 pgg-pgp mime-pgp + smime semi-def mime-view mime-play mime-partial mime-edit semi-setup mail-mime-setup)) diff --git a/smime.el b/smime.el new file mode 100644 index 0000000..9df2468 --- /dev/null +++ b/smime.el @@ -0,0 +1,314 @@ +;;; smime.el --- S/MIME interface. + +;; Copyright (C) 1999 Daiki Ueno + +;; Author: Daiki Ueno +;; Created: 1999/12/08 +;; Keywords: S/MIME, OpenSSL + +;; This file is part of SEMI (Secure Emacs MIME Interface). + +;; This program is free software; you can redistribute it and/or +;; modify it under the terms of the GNU General Public License as +;; published by the Free Software Foundation; either version 2, or (at +;; your option) any later version. + +;; This program is distributed in the hope that it will be useful, but +;; WITHOUT ANY WARRANTY; without even the implied warranty of +;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +;; General Public License for more details. + +;; You should have received a copy of the GNU General Public License +;; along with GNU Emacs; see the file COPYING. If not, write to the +;; Free Software Foundation, Inc., 59 Temple Place - Suite 330, +;; Boston, MA 02111-1307, USA. + + +;;; Commentary: + +;; This module is based on + +;; [SMIMEV3] RFC 2633: "S/MIME Version 3 Message Specification" +;; by Crocker, D., Flanigan, B., Hoffman, P., Housley, R., +;; Pawling, J. and Schaad, J. (1999/06) + +;; [SMIMEV2] RFC 2311: "S/MIME Version 2 Message Specification" +;; by Dusse, S., Hoffman, P., Ramsdell, B., Lundblade, L. +;; and L. Repka. (1998/03) + +;;; Code: + +(require 'path-util) + +(defgroup smime () + "S/MIME interface" + :group 'mime) + +(defcustom smime-program "smime" + "The S/MIME executable." + :group 'smime + :type 'string) + +(defcustom smime-shell-file-name "/bin/sh" + "File name to load inferior shells from. Bourne shell or its equivalent +\(not tcsh) is needed for \"2>\"." + :group 'smime + :type 'string) + +(defcustom smime-shell-command-switch "-c" + "Switch used to have the shell execute its command line argument." + :group 'smime + :type 'string) + +(defcustom smime-x509-program + (let ((file (exec-installed-p "openssl"))) + (and file (list file "x509" "-noout"))) + "External program for x509 parser." + :group 'smime + :type 'string) + +(defcustom smime-cache-passphrase t + "Cache passphrase." + :group 'smime + :type 'boolean) + +(defcustom smime-certificate-directory "~/.w3/certs" + "Certificate directory." + :group 'smime + :type 'directory) + +(defcustom smime-public-key-file nil + "Public key file." + :group 'smime + :type 'boolean) + +(defcustom smime-private-key-file nil + "Private key file." + :group 'smime + :type 'boolean) + +(defvar smime-errors-buffer " *S/MIME errors*") +(defvar smime-output-buffer " *S/MIME output*") + +;;; @ utility functions +;;; +(put 'smime-process-when-success 'lisp-indent-function 0) + +(defmacro smime-process-when-success (&rest body) + `(with-current-buffer smime-output-buffer + (if (zerop (buffer-size)) nil ,@body t))) + +(defvar smime-passphrase-cache-expiry 16) +(defvar smime-passphrase-cache (make-vector 7 0)) + +(defvar smime-read-passphrase nil) +(defun smime-read-passphrase (prompt &optional key) + (if (not smime-read-passphrase) + (if (functionp 'read-passwd) + (setq smime-read-passphrase 'read-passwd) + (if (load "passwd" t) + (setq smime-read-passphrase 'read-passwd) + (autoload 'ange-ftp-read-passwd "ange-ftp") + (setq smime-read-passphrase 'ange-ftp-read-passwd)))) + (or (and smime-cache-passphrase + (symbol-value (intern-soft key smime-passphrase-cache))) + (funcall smime-read-passphrase prompt))) + +(defun smime-add-passphrase-cache (key passphrase) + (set (intern key smime-passphrase-cache) + passphrase) + (run-at-time smime-passphrase-cache-expiry nil + #'smime-remove-passphrase-cache + key)) + +(defun smime-remove-passphrase-cache (key) + (let ((passphrase (symbol-value (intern-soft key smime-passphrase-cache)))) + (when passphrase + (fillarray passphrase ?_) + (unintern key smime-passphrase-cache)))) + +(defsubst smime-parse-attribute (string) + (delq nil (mapcar + (lambda (attr) + (if (string-match "=" attr) + (cons (intern (substring attr 0 (match-beginning 0))) + (substring attr (match-end 0))) + nil)) + (split-string string "/")))) + +(defsubst smime-query-signer (start end) + (smime-process-region start end smime-program (list "-qs")) + (with-current-buffer smime-output-buffer + (if (zerop (buffer-size)) nil + (goto-char (point-min)) + (when (re-search-forward "^/" nil t) + (smime-parse-attribute + (buffer-substring (point) (progn (end-of-line)(point))))) + ))) + +(defsubst smime-x509-hash (cert-file) + (with-current-buffer (get-buffer-create smime-output-buffer) + (buffer-disable-undo) + (erase-buffer) + (insert-file-contents cert-file) + (apply #'call-process-region + (point-min)(point-max) (car smime-x509-program) + t t nil (cons "-hash" (cdr smime-x509-program))) + (if (zerop (buffer-size)) nil + (buffer-substring (point-min) (1- (point-max)))))) + +(defsubst smime-x509-subject (cert-file) + (with-current-buffer (get-buffer-create smime-output-buffer) + (buffer-disable-undo) + (erase-buffer) + (insert-file-contents cert-file) + (apply #'call-process-region + (point-min)(point-max) (car smime-x509-program) + t t nil (cons "-subject" (cdr smime-x509-program))) + (if (zerop (buffer-size)) nil + (goto-char (point-min)) + (when (re-search-forward "^subject=" nil t) + (smime-parse-attribute + (buffer-substring (point)(progn (end-of-line)(point)))))))) + +(defsubst smime-search-certificate (attr) + (let ((files (if (file-directory-p smime-certificate-directory) + (directory-files smime-certificate-directory) + nil))) + (catch 'found + (while files + (if (or (string-equal + (cdr (assq 'CN (smime-x509-subject (car files)))) + (cdr (assq 'CN attr))) + (string-equal + (cdr (assq 'Email (smime-x509-subject (car files)))) + (cdr (assq 'Email attr)))) + (throw 'found (car files))) + (pop files))))) + +(defun smime-process-region (start end program args) + (let* ((errors-file-name + (concat temporary-file-directory + (make-temp-name "smime-errors"))) + (args (append args (list (concat "2>" errors-file-name)))) + (shell-file-name smime-shell-file-name) + (shell-command-switch smime-shell-command-switch) + (process-connection-type nil) + process status exit-status) + (with-current-buffer (get-buffer-create smime-output-buffer) + (buffer-disable-undo) + (erase-buffer)) + (as-binary-process + (setq process + (apply #'start-process-shell-command "*S/MIME*" + smime-output-buffer program args))) + (set-process-sentinel process 'ignore) + (process-send-region process start end) + (process-send-eof process) + (while (eq 'run (process-status process)) + (accept-process-output process 5)) + (setq status (process-status process) + exit-status (process-exit-status process)) + (delete-process process) + (with-current-buffer smime-output-buffer + (goto-char (point-min)) + (while (re-search-forward "\r$" (point-max) t) + (replace-match "")) + + (if (memq status '(stop signal)) + (error "%s exited abnormally: '%s'" program exit-status)) + (if (= 127 exit-status) + (error "%s could not be found" program)) + + (set-buffer (get-buffer-create smime-errors-buffer)) + (buffer-disable-undo) + (erase-buffer) + (insert-file-contents errors-file-name) + (delete-file errors-file-name) + + (if (and process (eq 'run (process-status process))) + (interrupt-process process)) + ) + )) + +;;; @ interface functions +;;; + +;;;###autoload +(defun smime-encrypt-region (start end) + "Encrypt the current region between START and END." + (let* ((key-file + (or smime-private-key-file + (expand-file-name (read-file-name "Public key file: ")))) + (args (list "-e" key-file))) + (smime-process-region start end smime-program args) + (smime-process-when-success nil))) + +;;;###autoload +(defun smime-decrypt-region (start end) + "Decrypt the current region between START and END." + (let* ((key-file + (or smime-private-key-file + (expand-file-name (read-file-name "Private key file: ")))) + (hash (smime-x509-hash key-file)) + (passphrase (smime-read-passphrase + (format "S/MIME passphrase for %s: " hash) + hash)) + (args (list "-d" key-file passphrase))) + (smime-process-region start end smime-program args) + (smime-process-when-success + (when smime-cache-passphrase + (smime-add-passphrase-cache hash passphrase))))) + +;;;###autoload +(defun smime-sign-region (start end &optional cleartext) + "Make the signature from text between START and END. +If the optional 3rd argument CLEARTEXT is non-nil, it does not create +a detached signature." + (let* ((key-file + (or smime-private-key-file + (expand-file-name (read-file-name "Private key file: ")))) + (hash (smime-x509-hash key-file)) + (passphrase (smime-read-passphrase + (format "S/MIME passphrase for %s: " hash) + hash)) + (args (list "-ds" key-file passphrase))) + (smime-process-region start end smime-program args) + (smime-process-when-success + (when smime-cache-passphrase + (smime-add-passphrase-cache hash passphrase))))) + +;;;###autoload +(defun smime-verify-region (start end signature) + "Verify the current region between START and END. +If the optional 3rd argument SIGNATURE is non-nil, it is treated as +the detached signature of the current region." + (let* ((basename (expand-file-name "smime" temporary-file-directory)) + (orig-file (make-temp-name basename)) + (args (list "-qs" signature)) + (orig-mode (default-file-modes)) + cert-file) + (unwind-protect + (progn + (set-default-file-modes 448) + (write-region-as-binary start end orig-file) + ) + (set-default-file-modes orig-mode)) + (with-temp-buffer + (insert-file-contents-as-binary signature) + (goto-char (point-max)) + (insert "\n") + (insert-file-contents-as-binary + (or (smime-search-certificate + (smime-query-signer (point-min)(point-max))) + (expand-file-name + (read-file-name "Certificate file: ")))) + (smime-process-region (point-min)(point-max) smime-program args)) + (smime-process-when-success + (when smime-cache-passphrase + (smime-add-passphrase-cache hash passphrase))) + )) + +(provide 'smime) + +;;; smime.el ends here -- 1.7.10.4