plstore.el: Don't cache wrong passphrase

* plstore.el (plstore--decrypt): Clear entry in
`plstore-passphrase-alist' if decryption failed (bug#20030).

2 files changed, 15 insertions, 3 deletions

diff --git a/lisp/gnus/ChangeLog b/lisp/gnus/ChangeLog
index 574b2e825c6..5b10d45e814 100644
--- a/lisp/gnus/ChangeLog
+++ b/lisp/gnus/ChangeLog
@@ -1,3 +1,8 @@
+2015-03-31  Daiki Ueno  <ueno@gnu.org>
+
+        * plstore.el (plstore--decrypt): Clear entry in
+        `plstore-passphrase-alist' if decryption failed (bug#20030).
+
 2015-03-28  Adam Sjøgren  <asjo@koldfront.dk>
 
         * gnus-sum.el (gnus-summary-make-menu-bar): Add "Display HTML images"
diff --git a/lisp/gnus/plstore.el b/lisp/gnus/plstore.el
index 12a0413dcaf..175e272cb9a 100644
--- a/lisp/gnus/plstore.el
+++ b/lisp/gnus/plstore.el
@@ -270,9 +270,16 @@ symmetric encryption will be used.")
          context
          (cons #'plstore-progress-callback-function
                (format "Decrypting %s" (plstore-get-file plstore))))
-        (setq plain
-              (epg-decrypt-string context
-                                  (plstore--get-encrypted-data plstore)))
+        (condition-case error
+            (setq plain
+                  (epg-decrypt-string context
+                                      (plstore--get-encrypted-data plstore)))
+          (error
+           (let ((entry (assoc (plstore-get-file plstore)
+                               plstore-passphrase-alist)))
+             (if entry
+                 (setcdr entry nil)))
+           (signal (car error) (cdr error))))
         (plstore--set-secret-alist plstore (car (read-from-string plain)))
         (plstore--merge-secret plstore)
         (plstore--set-encrypted-data plstore nil))))