(epa-mail--find-usable-key): New function.

[elisp/epg.git] / epa-mail.el

diff --git a/epa-mail.el b/epa-mail.el
index 0b0e099..97b3204 100644 (file)
--- a/epa-mail.el
+++ b/epa-mail.el
@@ -36,10 +36,27 @@
     (define-key keymap "\C-c\C-eo" 'epa-insert-keys)
     keymap))
 
+(defvar epa-mail-mode-hook nil)
+(defvar epa-mail-mode-on-hook nil)
+(defvar epa-mail-mode-off-hook nil)
+
 (define-minor-mode epa-mail-mode
   "A minor-mode for composing encrypted/clearsigned mails."
   nil " epa-mail" epa-mail-mode-map)
 
+(defun epa-mail--find-usable-key (keys usage)
+  "Find a usable key from KEYS for USAGE."
+  (catch 'found
+    (while keys
+      (let ((pointer (epg-key-sub-key-list (car keys))))
+       (while pointer
+         (if (and (memq usage (epg-sub-key-capability (car pointer)))
+                  (not (memq (epg-sub-key-validity (car pointer))
+                             '(revoked expired))))
+             (throw 'found (car keys)))
+         (setq pointer (cdr pointer))))
+      (setq keys (cdr keys)))))
+
 ;;;###autoload
 (defun epa-mail-decrypt ()
   "Decrypt OpenPGP armors in the current buffer.
@@ -94,7 +111,7 @@ Don't use this command in Lisp programs!"
    (save-excursion
      (let ((verbose current-prefix-arg)
           (context (epg-make-context epa-protocol))
-          recipients recipient-keys)
+          recipients recipient-key)
        (goto-char (point-min))
        (save-restriction
         (narrow-to-region (point)
@@ -125,21 +142,22 @@ Don't use this command in Lisp programs!"
 If no one is selected, symmetric encryption will be performed.  "
                  recipients)
               (if recipients
-                  (apply #'nconc
-                         (mapcar
-                          (lambda (recipient)
-                            (setq recipient-keys
-                                  (epg-list-keys
-                                   (epg-make-context epa-protocol)
-                                   (concat "<" recipient ">")))
-                            (unless (or recipient-keys
-                                        (y-or-n-p
-                                         (format
-                                          "No public key for %s; skip it? "
-                                          recipient)))
-                              (error "No public key for %s" recipient))
-                            recipient-keys)
-                          recipients))))
+                  (mapcar
+                   (lambda (recipient)
+                     (setq recipient-key
+                           (epa-mail--find-usable-key
+                            (epg-list-keys
+                             (epg-make-context epa-protocol)
+                             (concat "<" recipient ">"))
+                            'encrypt))
+                     (unless (or recipient-key
+                                 (y-or-n-p
+                                  (format
+                                   "No public key for %s; skip it? "
+                                   recipient)))
+                       (error "No public key for %s" recipient))
+                     recipient-key)
+                   recipients)))
             (setq sign (if verbose (y-or-n-p "Sign? ")))
             (if sign
                 (epa-select-keys context