[Emacs-diffs] /srv/bzr/emacs/trunk r102771: gnus/mml2015.el: Fix secret key validity check (Bug#7797).

[Daiki Ueno]

------------------------------------------------------------
revno: 102771
committer: Daiki Ueno <address@hidden>
branch nick: trunk
timestamp: Fri 2011-01-07 18:28:29 +0900
message:
  gnus/mml2015.el: Fix secret key validity check (Bug#7797).
  
  * mml2015.el (epg-sub-key-fingerprint): Autoload.
  (mml2015-epg-find-usable-secret-key): New function.
  (mml2015-epg-sign): Use mml2015-epg-find-usable-secret-key instead of
  mml2015-epg-find-usable-key (Bug#7797).
  (mml2015-epg-encrypt): Ditto.
modified:
  lisp/gnus/ChangeLog
  lisp/gnus/mml2015.el

=== modified file 'lisp/gnus/ChangeLog'
--- a/lisp/gnus/ChangeLog       2011-01-04 02:24:15 +0000
+++ b/lisp/gnus/ChangeLog       2011-01-07 09:28:29 +0000
@@ -1,3 +1,11 @@
+2011-01-07  Daiki Ueno  <address@hidden>
+
+       * mml2015.el (epg-sub-key-fingerprint): Autoload.
+       (mml2015-epg-find-usable-secret-key): New function.
+       (mml2015-epg-sign): Use mml2015-epg-find-usable-secret-key instead of
+       mml2015-epg-find-usable-key (Bug#7797).
+       (mml2015-epg-encrypt): Ditto.
+
 2011-01-03  Lars Magne Ingebrigtsen  <address@hidden>
 
        * flow-fill.el (fill-flowed-encode): Do encoding citation-aware.

=== modified file 'lisp/gnus/mml2015.el'
--- a/lisp/gnus/mml2015.el      2010-12-27 09:46:02 +0000
+++ b/lisp/gnus/mml2015.el      2011-01-07 09:28:29 +0000
@@ -742,6 +742,7 @@
 (autoload 'epg-key-sub-key-list "epg")
 (autoload 'epg-sub-key-capability "epg")
 (autoload 'epg-sub-key-validity "epg")
+(autoload 'epg-sub-key-fingerprint "epg")
 (autoload 'epg-configuration "epg-config")
 (autoload 'epg-expand-group "epg-config")
 (autoload 'epa-select-keys "epa")
@@ -784,6 +785,24 @@
          (setq pointer (cdr pointer))))
       (setq keys (cdr keys)))))
 
+;; XXX: since gpg --list-secret-keys does not return validity of each
+;; key, `mml2015-epg-find-usable-key' defined above is not enough for
+;; secret keys.  The function `mml2015-epg-find-usable-secret-key'
+;; below looks at appropriate public keys to check usability.
+(defun mml2015-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 (mml2015-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))
+
 (defun mml2015-epg-decrypt (handle ctl)
   (catch 'error
     (let ((inhibit-redisplay t)
@@ -960,9 +979,9 @@
                     (delq nil
                           (mapcar
                            (lambda (signer)
-                             (setq signer-key (mml2015-epg-find-usable-key
-                                               (epg-list-keys context signer t)
-                                               'sign))
+                             (setq signer-key
+                                   (mml2015-epg-find-usable-secret-key
+                                    context signer 'sign))
                              (unless (or signer-key
                                          (y-or-n-p
                                           (format
@@ -1081,9 +1100,9 @@
                       (delq nil
                             (mapcar
                              (lambda (signer)
-                               (setq signer-key (mml2015-epg-find-usable-key
-                                                 (epg-list-keys context signer 
t)
-                                                 'sign))
+                               (setq signer-key
+                                     (mml2015-epg-find-usable-secret-key
+                                      context signer 'sign))
                                (unless (or signer-key
                                            (y-or-n-p
                                             (format