gnus-art.el (gnus-button-alist): Also support quotes 'like this'
[gnus] / lisp / mml-smime.el
index d14ccb7..3f0809e 100644 (file)
@@ -1,27 +1,24 @@
 ;;; mml-smime.el --- S/MIME support for MML
 
-;; Copyright (C) 2000, 2001, 2002, 2003, 2004,
-;;   2005, 2006, 2007 Free Software Foundation, Inc.
+;; Copyright (C) 2000-2015 Free Software Foundation, Inc.
 
 ;; Author: Simon Josefsson <simon@josefsson.org>
 ;; Keywords: Gnus, MIME, S/MIME, MML
 
 ;; 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
-;; by the Free Software Foundation; either version 2, or (at your
-;; option) any later version.
+;; GNU Emacs 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 3 of the License, or
+;; (at your option) any later version.
 
-;; GNU Emacs 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.
+;; GNU Emacs 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., 51 Franklin Street, Fifth Floor,
-;; Boston, MA 02110-1301, USA.
+;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
 
 ;;; Commentary:
 
 (autoload 'message-narrow-to-headers "message")
 (autoload 'message-fetch-field "message")
 
-(defvar mml-smime-use 'openssl)
+(defcustom mml-smime-use (if (featurep 'epg) 'epg 'openssl)
+  "Whether to use OpenSSL or EPG to decrypt S/MIME messages.
+Defaults to EPG if it's loaded."
+  :group 'mime-security
+  :type '(choice (const :tag "EPG" epg)
+                 (const :tag "OpenSSL" openssl)))
 
 (defvar mml-smime-function-alist
   '((openssl mml-smime-openssl-sign
         mml-smime-epg-verify
         mml-smime-epg-verify-test)))
 
-(defcustom mml-smime-verbose mml-secure-verbose
-  "If non-nil, ask the user about the current operation more verbosely."
-  :group 'mime-security
-  :type 'boolean)
-
 (defcustom mml-smime-cache-passphrase mml-secure-cache-passphrase
   "If t, cache passphrase."
   :group 'mime-security
@@ -73,6 +70,18 @@ Whether the passphrase is cached at all is controlled by
   :group 'mime-security
   :type '(repeat (string :tag "Key ID")))
 
+(defcustom mml-smime-sign-with-sender nil
+  "If t, use message sender so find a key to sign with."
+  :group 'mime-security
+  :version "24.4"
+  :type 'boolean)
+
+(defcustom mml-smime-encrypt-to-self nil
+  "If t, add your own key ID to recipient list when encryption."
+  :group 'mime-security
+  :version "24.4"
+  :type 'boolean)
+
 (defun mml-smime-sign (cont)
   (let ((func (nth 1 (assq mml-smime-use mml-smime-function-alist))))
     (if func
@@ -142,6 +151,8 @@ Whether the passphrase is cached at all is controlled by
       nil))
   (goto-char (point-max)))
 
+(defvar gnus-extract-address-components)
+
 (defun mml-smime-openssl-sign-query ()
   ;; query information (what certificate) from user when MML tag is
   ;; added, for use later by the signing process
@@ -162,10 +173,10 @@ Whether the passphrase is cached at all is controlled by
                                             "")))))
                (and from (smime-get-key-by-email from)))
              (smime-get-key-by-email
-              (completing-read "Sign this part with what signature? "
-                               smime-keys nil nil
-                               (and (listp (car-safe smime-keys))
-                                    (caar smime-keys))))))))
+              (gnus-completing-read "Sign this part with what signature"
+                                     (mapcar 'car smime-keys) nil nil nil
+                                     (and (listp (car-safe smime-keys))
+                                          (caar smime-keys))))))))
 
 (defun mml-smime-get-file-cert ()
   (ignore-errors
@@ -214,13 +225,16 @@ Whether the passphrase is cached at all is controlled by
       (quit))
     result))
 
+(autoload 'gnus-completing-read "gnus-util")
+
 (defun mml-smime-openssl-encrypt-query ()
   ;; todo: try dns/ldap automatically first, before prompting user
   (let (certs done)
     (while (not done)
-      (ecase (read (gnus-completing-read-with-default
-                   "ldap" "Fetch certificate from"
-                   '(("dns") ("ldap") ("file")) nil t))
+      (ecase (read (gnus-completing-read
+                   "Fetch certificate from"
+                   '("dns" "ldap" "file") t nil nil
+                    "ldap"))
        (dns (setq certs (append certs
                                 (mml-smime-get-dns-cert))))
        (ldap (setq certs (append certs
@@ -298,35 +312,30 @@ Whether the passphrase is cached at all is controlled by
 (defun mml-smime-openssl-verify-test (handle ctl)
   smime-openssl-program)
 
-(eval-and-compile
-  (autoload 'epg-make-context "epg"))
-
-(eval-when-compile
-  (defvar epg-user-id-alist)
-  (defvar epg-digest-algorithm-alist)
-  (defvar inhibit-redisplay)
-  (autoload 'epg-context-set-armor "epg")
-  (autoload 'epg-context-set-textmode "epg")
-  (autoload 'epg-context-set-signers "epg")
-  (autoload 'epg-context-result-for "epg")
-  (autoload 'epg-new-signature-digest-algorithm "epg")
-  (autoload 'epg-verify-result-to-string "epg")
-  (autoload 'epg-list-keys "epg")
-  (autoload 'epg-decrypt-string "epg")
-  (autoload 'epg-verify-string "epg")
-  (autoload 'epg-sign-string "epg")
-  (autoload 'epg-encrypt-string "epg")
-  (autoload 'epg-passphrase-callback-function "epg")
-  (autoload 'epg-context-set-passphrase-callback "epg")
-  (autoload 'epg-configuration "epg-config")
-  (autoload 'epg-expand-group "epg-config")
-  (autoload 'epa-select-keys "epa"))
-
-(eval-when-compile
-  (defvar password-cache-expiry)
-  (autoload 'password-read "password")
-  (autoload 'password-cache-add "password")
-  (autoload 'password-cache-remove "password"))
+(defvar epg-user-id-alist)
+(defvar epg-digest-algorithm-alist)
+(defvar inhibit-redisplay)
+(defvar password-cache-expiry)
+
+(autoload 'epg-make-context "epg")
+(autoload 'epg-passphrase-callback-function "epg")
+(declare-function epg-context-set-signers "epg" (context signers))
+(declare-function epg-context-result-for "epg" (context name))
+(declare-function epg-new-signature-digest-algorithm "epg" (cl-x) t)
+(declare-function epg-verify-result-to-string "epg" (verify-result))
+(declare-function epg-list-keys "epg" (context &optional name mode))
+(declare-function epg-verify-string "epg"
+                 (context signature &optional signed-text))
+(declare-function epg-sign-string "epg" (context plain &optional mode))
+(declare-function epg-encrypt-string "epg"
+                 (context plain recipients &optional sign always-trust))
+(declare-function epg-context-set-passphrase-callback "epg"
+                 (context passphrase-callback))
+(declare-function epg-sub-key-fingerprint "epg" (cl-x) t)
+(declare-function epg-configuration "epg-config" ())
+(declare-function epg-expand-group "epg-config" (config group))
+(declare-function epa-select-keys "epa"
+                 (context prompt &optional names secret))
 
 (defvar mml-smime-epg-secret-key-id-list nil)
 
@@ -351,6 +360,10 @@ Whether the passphrase is cached at all is controlled by
              (cons key-id mml-smime-epg-secret-key-id-list))
        (copy-sequence passphrase)))))
 
+(declare-function epg-key-sub-key-list   "epg" (key) t)
+(declare-function epg-sub-key-capability "epg" (sub-key) t)
+(declare-function epg-sub-key-validity   "epg" (sub-key) t)
+
 (defun mml-smime-epg-find-usable-key (keys usage)
   (catch 'found
     (while keys
@@ -363,33 +376,64 @@ Whether the passphrase is cached at all is controlled by
          (setq pointer (cdr pointer))))
       (setq keys (cdr keys)))))
 
+;; XXX: since gpg --list-secret-keys does not return validity of each
+;; key, `mml-smime-epg-find-usable-key' defined above is not enough for
+;; secret keys.  The function `mml-smime-epg-find-usable-secret-key'
+;; below looks at appropriate public keys to check usability.
+(defun mml-smime-epg-find-usable-secret-key (context name usage)
+  (let ((secret-keys (epg-list-keys context name t))
+       secret-key)
+    (while (and (not secret-key) secret-keys)
+      (if (mml-smime-epg-find-usable-key
+          (epg-list-keys context (epg-sub-key-fingerprint
+                                  (car (epg-key-sub-key-list
+                                        (car secret-keys)))))
+          usage)
+         (setq secret-key (car secret-keys)
+               secret-keys nil)
+       (setq secret-keys (cdr secret-keys))))
+    secret-key))
+
+(autoload 'mml-compute-boundary "mml")
+
+;; We require mm-decode, which requires mm-bodies, which autoloads
+;; message-options-get (!).
+(declare-function message-options-set "message" (symbol value))
+
 (defun mml-smime-epg-sign (cont)
   (let* ((inhibit-redisplay t)
         (context (epg-make-context 'CMS))
         (boundary (mml-compute-boundary cont))
+        (sender (message-options-get 'message-sender))
+        (signer-names (or mml-smime-signers
+                          (if (and mml-smime-sign-with-sender sender)
+                              (list (concat "<" sender ">")))))
         signer-key
         (signers
          (or (message-options-get 'mml-smime-epg-signers)
              (message-options-set
-             'mml-smime-epg-signers
-             (if mml-smime-verbose
-                 (epa-select-keys context "\
+              'mml-smime-epg-signers
+              (if (eq mm-sign-option 'guided)
+                  (epa-select-keys context "\
 Select keys for signing.
 If no one is selected, default secret key is used.  "
-                                  mml-smime-signers t)
-               (if mml-smime-signers
-                   (mapcar
-                    (lambda (signer)
-                      (setq signer-key (mml-smime-epg-find-usable-key
-                                        (epg-list-keys context signer t)
-                                        'sign))
-                      (unless (or signer-key
-                                  (y-or-n-p
-                                   (format "No secret key for %s; skip it? "
+                                   signer-names
+                                   t)
+                (if (or sender mml-smime-signers)
+                    (delq nil
+                          (mapcar
+                           (lambda (signer)
+                             (setq signer-key
+                                   (mml-smime-epg-find-usable-secret-key
+                                    context signer 'sign))
+                             (unless (or signer-key
+                                         (y-or-n-p
+                                          (format
+                                           "No secret key for %s; skip it? "
                                            signer)))
-                        (error "No secret key for %s" signer))
-                      signer-key)
-                    mml-smime-signers))))))
+                               (error "No secret key for %s" signer))
+                             signer-key)
+                           signer-names)))))))
         signature micalg)
     (epg-context-set-signers context signers)
     (if mml-smime-cache-passphrase
@@ -397,7 +441,10 @@ If no one is selected, default secret key is used.  "
         context
         #'mml-smime-epg-passphrase-callback))
     (condition-case error
-       (setq signature (epg-sign-string context (buffer-string) t)
+       (setq signature (epg-sign-string context
+                                        (mm-replace-in-string (buffer-string)
+                                                              "\n" "\r\n")
+                                        t)
              mml-smime-epg-secret-key-id-list nil)
       (error
        (while mml-smime-epg-secret-key-id-list
@@ -431,13 +478,17 @@ Content-Disposition: attachment; filename=smime.p7s
     (goto-char (point-max))))
 
 (defun mml-smime-epg-encrypt (cont)
-  (let ((inhibit-redisplay t)
-       (context (epg-make-context 'CMS))
-       (config (epg-configuration))
-       (recipients (message-options-get 'mml-smime-epg-recipients))
-       cipher signers
-       (boundary (mml-compute-boundary cont))
-       recipient-key)
+  (let* ((inhibit-redisplay t)
+        (context (epg-make-context 'CMS))
+        (config (epg-configuration))
+        (recipients (message-options-get 'mml-smime-epg-recipients))
+        cipher signers
+        (sender (message-options-get 'message-sender))
+        (signer-names (or mml-smime-signers
+                          (if (and mml-smime-sign-with-sender sender)
+                              (list (concat "<" sender ">")))))
+        (boundary (mml-compute-boundary cont))
+        recipient-key)
     (unless recipients
       (setq recipients
            (apply #'nconc
@@ -450,7 +501,11 @@ Content-Disposition: attachment; filename=smime.p7s
                         (message-options-set 'message-recipients
                                              (read-string "Recipients: ")))
                     "[ \f\t\n\r\v,]+"))))
-      (if mml-smime-verbose
+      (when mml-smime-encrypt-to-self
+       (unless signer-names
+         (error "Neither message sender nor mml-smime-signers are set"))
+       (setq recipients (nconc recipients signer-names)))
+      (if (eq mm-encrypt-option 'guided)
          (setq recipients
                (epa-select-keys context "\
 Select recipients for encryption.
@@ -508,14 +563,19 @@ Content-Disposition: attachment; filename=smime.p7m
                                           ctl 'protocol)
                                          "application/pkcs7-signature")
                                  t)))
-               (null (setq signature (mm-find-part-by-type
-                                      (cdr handle)
-                                      "application/pkcs7-signature"
-                                      nil t))))
+               (null (setq signature (or (mm-find-part-by-type
+                                          (cdr handle)
+                                          "application/pkcs7-signature"
+                                          nil t)
+                                         (mm-find-part-by-type
+                                          (cdr handle)
+                                          "application/x-pkcs7-signature"
+                                          nil t)))))
        (mm-set-handle-multipart-parameter
         mm-security-handle 'gnus-info "Corrupted")
        (throw 'error handle))
-      (setq context (epg-make-context 'CMS))
+      (setq part (mm-replace-in-string part "\n" "\r\n")
+           context (epg-make-context 'CMS))
       (condition-case error
          (setq plain (epg-verify-string context (mm-get-part signature) part))
        (error
@@ -537,5 +597,4 @@ Content-Disposition: attachment; filename=smime.p7m
 
 (provide 'mml-smime)
 
-;;; arch-tag: f1bf94d4-f2cd-4c6f-b059-ad69492817e2
 ;;; mml-smime.el ends here