;;; smime.el --- S/MIME support library
-;; Copyright (c) 2000, 2001 Free Software Foundation, Inc.
+;; Copyright (c) 2000, 2001, 2003 Free Software Foundation, Inc.
;; Author: Simon Josefsson <simon@josefsson.org>
;; Keywords: SMIME X.509 PEM OpenSSL
-;; This file is not a part of GNU Emacs, but the same permissions apply.
+;; This file is part of GNU Emacs.
;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published
;; PKCSx or similar, it's intended to perform common operations
;; done on messages encoded in these formats. The terminology chosen
;; reflect this.
+;;
+;; The home of this file is in Gnus CVS, but also available from
+;; http://josefsson.org/smime.html.
;;; Quick introduction:
;; environment variables to pass the password to OpenSSL, which is
;; slightly insecure. Hence a new todo: use a better -passin method.
;;
+;; Cache password for e.g. 1h
+;;
;; Suggestions and comments are appreciated, mail me at simon@josefsson.org.
-;; <rant>
+;; begin rant
;;
;; I would include pointers to introductory text on concepts used in
;; this library here, but the material I've read are so horrible I
;; Also, I'm not going to mention anything about the wonders of
;; cryptopolitics. Oops, I just did.
;;
-;; </rant>
+;; end rant
;;; Revision history:
-;; version 0 not released
+;; 2000-06-05 initial version, committed to Gnus CVS contrib/
+;; 2000-10-28 retrieve certificates via DNS CERT RRs
+;; 2001-10-14 posted to gnu.emacs.sources
;;; Code:
(require 'dig)
-(require 'comint)
(eval-when-compile (require 'cl))
(defgroup smime nil
Directory should contain files (in PEM format) named to the X.509
hash of the certificate. This can be done using OpenSSL such as:
-$ ln -s ca.pem `openssl x509 -noout -hash -in ca.pem`
+$ ln -s ca.pem `openssl x509 -noout -hash -in ca.pem`.0
where `ca.pem' is the file containing a PEM encoded X.509 CA
certificate."
(const :tag "RC2 128 bits" "-rc2-128"))
:group 'smime)
+(defcustom smime-crl-check nil
+ "*Check revocation status of signers certificate using CRLs.
+Enabling this will have OpenSSL check the signers certificate
+against a certificate revocation list (CRL).
+
+For this to work the CRL must be up-to-date and since they are
+normally updated quite often (ie. several times a day) you
+probably need some tool to keep them up-to-date. Unfortunately
+Gnus cannot do this for you.
+
+The CRL should either be appended (in PEM format) to your
+`smime-CA-file' or be located in a file (also in PEM format) in
+your `smime-certificate-directory' named to the X.509 hash of the
+certificate with .r0 as file name extension.
+
+At least OpenSSL version 0.9.7 is required for this to work."
+ :type '(choice (const :tag "No check" nil)
+ (const :tag "Check certificate" "-crl_check")
+ (const :tag "Check certificate chain" "-crl_check_all"))
+ :group 'smime)
+
(defcustom smime-dns-server nil
"*DNS server to query certificates from.
If nil, use system defaults."
string)
:group 'smime)
-(defcustom smime-extra-arguments nil
- "*List of additional arguments passed to OpenSSL.
-For instance, if you don't have a /dev/random you might be forced
-to set this to e.g. `(\"-rand\" \"/etc/entropy\")'."
- :type '(repeat string)
- :group 'smime)
-
(defvar smime-details-buffer "*OpenSSL output*")
+;; Use mm-util?
+(eval-and-compile
+ (defalias 'smime-make-temp-file
+ (if (fboundp 'make-temp-file)
+ 'make-temp-file
+ (lambda (prefix &optional dir-flag) ;; Simple implementation
+ (expand-file-name
+ (make-temp-name prefix)
+ (if (fboundp 'temp-directory)
+ (temp-directory)
+ temporary-file-directory))))))
+
;; Password dialog function
(defun smime-ask-passphrase ()
"Asks the passphrase to unlock the secret key."
(let ((passphrase
- (comint-read-noecho
- "Passphrase for secret key (RET for no passphrase): " t)))
+ (read-passwd
+ "Passphrase for secret key (RET for no passphrase): ")))
(if (string= passphrase "")
nil
passphrase)))
;; OpenSSL wrappers.
(defun smime-call-openssl-region (b e buf &rest args)
- (case (apply 'call-process-region b e smime-openssl-program nil
- buf nil (append smime-extra-arguments args))
+ (case (apply 'call-process-region b e smime-openssl-program nil buf nil args)
(0 t)
(1 (message "OpenSSL: An error occurred parsing the command options.") nil)
(2 (message "OpenSSL: One of the input files could not be read.") nil)
;; Sign+encrypt region
-(defun smime-sign-region (b e keyfiles)
- "Sign region with certified key in KEYFILES.
+(defun smime-sign-region (b e keyfile)
+ "Sign region with certified key in KEYFILE.
If signing fails, the buffer is not modified. Region is assumed to
-have proper MIME tags. KEYFILES is expected to contain a PEM encoded
-private key and certificate as its car, and a list of additional certificates
-to include in its caar."
- (let ((keyfile (car keyfiles))
- (certfiles (and (cdr keyfiles) (cadr keyfiles)))
+have proper MIME tags. KEYFILE is expected to contain a PEM encoded
+private key and certificate as its car, and a list of additional
+certificates to include in its caar. If no additional certificates is
+included, KEYFILE may be the file containing the PEM encoded private
+key and certificate itself."
+ (smime-new-details-buffer)
+ (let ((keyfile (or (car-safe keyfile) keyfile))
+ (certfiles (and (cdr-safe keyfile) (cadr keyfile)))
(buffer (generate-new-buffer (generate-new-buffer-name " *smime*")))
- (passphrase (smime-ask-passphrase)))
+ (passphrase (smime-ask-passphrase))
+ (tmpfile (smime-make-temp-file "smime")))
(if passphrase
(setenv "GNUS_SMIME_PASSPHRASE" passphrase))
(prog1
- (when (apply 'smime-call-openssl-region b e buffer "smime" "-sign"
- "-signer" (expand-file-name keyfile)
- (append
- (smime-make-certfiles certfiles)
- (if passphrase
- (list "-passin" "env:GNUS_SMIME_PASSPHRASE"))))
+ (when (prog1
+ (apply 'smime-call-openssl-region b e (list buffer tmpfile)
+ "smime" "-sign" "-signer" (expand-file-name keyfile)
+ (append
+ (smime-make-certfiles certfiles)
+ (if passphrase
+ (list "-passin" "env:GNUS_SMIME_PASSPHRASE"))))
+ (if passphrase
+ (setenv "GNUS_SMIME_PASSPHRASE" "" t))
+ (with-current-buffer smime-details-buffer
+ (insert-file-contents tmpfile)
+ (delete-file tmpfile)))
(delete-region b e)
(insert-buffer-substring buffer)
+ (goto-char b)
(when (looking-at "^MIME-Version: 1.0$")
(delete-region (point) (progn (forward-line 1) (point))))
t)
- (if passphrase
- (setenv "GNUS_SMIME_PASSPHRASE" "" t))
- (with-current-buffer (get-buffer-create smime-details-buffer)
+ (with-current-buffer smime-details-buffer
(goto-char (point-max))
(insert-buffer-substring buffer))
(kill-buffer buffer))))
If encryption fails, the buffer is not modified. Region is assumed to
have proper MIME tags. CERTFILES is a list of filenames, each file
is expected to contain of a PEM encoded certificate."
- (let ((buffer (generate-new-buffer (generate-new-buffer-name " *smime*"))))
+ (smime-new-details-buffer)
+ (let ((buffer (generate-new-buffer (generate-new-buffer-name " *smime*")))
+ (tmpfile (smime-make-temp-file "smime")))
(prog1
- (when (apply 'smime-call-openssl-region b e buffer "smime" "-encrypt"
- smime-encrypt-cipher (mapcar 'expand-file-name certfiles))
+ (when (prog1
+ (apply 'smime-call-openssl-region b e (list buffer tmpfile)
+ "smime" "-encrypt" smime-encrypt-cipher
+ (mapcar 'expand-file-name certfiles))
+ (with-current-buffer smime-details-buffer
+ (insert-file-contents tmpfile)
+ (delete-file tmpfile)))
(delete-region b e)
(insert-buffer-substring buffer)
+ (goto-char b)
(when (looking-at "^MIME-Version: 1.0$")
(delete-region (point) (progn (forward-line 1) (point))))
t)
- (with-current-buffer (get-buffer-create smime-details-buffer)
+ (with-current-buffer smime-details-buffer
(goto-char (point-max))
(insert-buffer-substring buffer))
(kill-buffer buffer))))
(smime-sign-region
(point-min) (point-max)
(if keyfile
- (list keyfile (smime-get-certfiles keyfile smime-keys))
- (smime-get-key-by-email
- (completing-read "Sign using which signature? " smime-keys nil nil
- (and (listp (car-safe smime-keys))
- (cdr smime-keys))))))))
+ keyfile
+ (smime-get-key-with-certs-by-email
+ (completing-read
+ (concat "Sign using which key? "
+ (if smime-keys (concat "(default " (caar smime-keys) ") ")
+ ""))
+ smime-keys nil nil (car-safe (car-safe smime-keys))))))))
(defun smime-encrypt-buffer (&optional certfiles buffer)
"S/MIME encrypt BUFFER for recipients specified in CERTFILES.
(expand-file-name smime-CA-directory))))))
(unless CAs
(error "No CA configured"))
+ (if smime-crl-check
+ (add-to-list 'CAs smime-crl-check))
(if (apply 'smime-call-openssl-region b e (list smime-details-buffer t)
"smime" "-verify" "-out" "/dev/null" CAs)
t
(insert-buffer-substring smime-details-buffer)
nil))
+(eval-when-compile
+ (defvar from))
+
(defun smime-decrypt-region (b e keyfile)
"Decrypt S/MIME message in region between B and E with key in KEYFILE.
On success, replaces region with decrypted data and return non-nil.
(smime-new-details-buffer)
(let ((buffer (generate-new-buffer (generate-new-buffer-name " *smime*")))
CAs (passphrase (smime-ask-passphrase))
- (tmpfile (make-temp-file "smime")))
+ (tmpfile (smime-make-temp-file "smime")))
(if passphrase
(setenv "GNUS_SMIME_PASSPHRASE" passphrase))
(if (prog1
(delete-file tmpfile)))
(progn
(delete-region b e)
+ (when (boundp 'from)
+ ;; `from' is dynamically bound in mm-dissect.
+ (insert "From: " from "\n"))
(insert-buffer-substring buffer)
(kill-buffer buffer)
t)
(expand-file-name
(or keyfile
(smime-get-key-by-email
- (completing-read "Decrypt with which key? " smime-keys nil nil
- (and (listp (car-safe smime-keys))
- (caar smime-keys)))))))))
+ (completing-read
+ (concat "Decipher using which key? "
+ (if smime-keys (concat "(default " (caar smime-keys) ") ")
+ ""))
+ smime-keys nil nil (car-safe (car-safe smime-keys)))))))))
;; Various operations
"Get email addresses contained in certificate between points B and E.
A string or a list of strings is returned."
(smime-new-details-buffer)
- (when (smime-call-openssl-region
+ (when (smime-call-openssl-region
b e smime-details-buffer "x509" "-email" "-noout")
(delete-region b e)
(insert-buffer-substring smime-details-buffer)
(caddr curkey)
(smime-get-certfiles keyfile otherkeys)))))
-(defalias 'smime-point-at-eol
- (if (fboundp 'point-at-eol)
- 'point-at-eol
- 'line-end-position))
-
(defun smime-buffer-as-string-region (b e)
"Return each line in region between B and E as a list of strings."
(save-excursion
(goto-char b)
(let (res)
(while (< (point) e)
- (let ((str (buffer-substring (point) (smime-point-at-eol))))
+ (let ((str (buffer-substring (point) (point-at-eol))))
(unless (string= "" str)
(push str res)))
(forward-line))
(defun smime-get-key-by-email (email)
(cadr (assoc email smime-keys)))
+(defun smime-get-key-with-certs-by-email (email)
+ (cdr (assoc email smime-keys)))
+
(provide 'smime)
+;;; arch-tag: e3f9b938-5085-4510-8a11-6625269c9a9e
;;; smime.el ends here
projects / gnus / blobdiff