lisp/gnus/mml2015.el (mml2015-epg-find-usable-key): handle revoked user-id

2 files changed, 67 insertions, 20 deletions

diff --git a/lisp/gnus/ChangeLog b/lisp/gnus/ChangeLog
index dd6d20969ff..8de9e89a23d 100644
--- a/lisp/gnus/ChangeLog
+++ b/lisp/gnus/ChangeLog
@@ -1,3 +1,14 @@
+2013-02-17  Daiki Ueno  <ueno@gnu.org>
+
+        * mml2015.el (epg-key-user-id-list, epg-user-id-string)
+        (epg-user-id-validity): Autoload.
+        (mml2015-epg-check-user-id): New function.
+        (mml2015-epg-check-sub-key): New function split from
+        mml2015-epg-find-usable-key.
+        (mml2015-epg-find-usable-key): Accept context, name, usage, and
+        optional name-is-key-id, to handle the case when user-id is unusable.
+        Reported by Łukasz Stelmach <stlman@poczta.fm>.
+
 2013-02-17  Glenn Morris  <rgm@gnu.org>
 
         * shr.el (shr-put-image): Use image-multi-frame-p if available.
diff --git a/lisp/gnus/mml2015.el b/lisp/gnus/mml2015.el
index 275a4867e85..b20c02aa26f 100644
--- a/lisp/gnus/mml2015.el
+++ b/lisp/gnus/mml2015.el
@@ -757,6 +757,9 @@ If set, it overrides the setting of `mml2015-sign-with-sender'."
 (autoload 'epg-sub-key-fingerprint "epg")
 (autoload 'epg-signature-key-id "epg")
 (autoload 'epg-signature-to-string "epg")
+(autoload 'epg-key-user-id-list "epg")
+(autoload 'epg-user-id-string "epg")
+(autoload 'epg-user-id-validity "epg")
 (autoload 'epg-configuration "epg-config")
 (autoload 'epg-expand-group "epg-config")
 (autoload 'epa-select-keys "epa")
@@ -786,21 +789,53 @@ If set, it overrides the setting of `mml2015-sign-with-sender'."
               (cons password-cache-key-id mml2015-epg-secret-key-id-list))
         (copy-sequence passphrase)))))
 
-(defun mml2015-epg-find-usable-key (keys usage)
-  (catch 'found
+(defun mml2015-epg-check-user-id (key recipient)
+  (let ((pointer (epg-key-user-id-list key))
+        result)
+    (while pointer
+      (if (and (equal (car (mail-header-parse-address
+                            (epg-user-id-string (car pointer))))
+                      (car (mail-header-parse-address
+                            recipient)))
+               (not (memq (epg-user-id-validity (car pointer))
+                          '(revoked expired))))
+          (setq result t
+                pointer nil)
+        (setq pointer (cdr pointer))))
+    result))
+
+(defun mml2015-epg-check-sub-key (key usage)
+  (let ((pointer (epg-key-sub-key-list key))
+        result)
+    ;; The primary key will be marked as disabled, when the entire
+    ;; key is disabled (see 12 Field, Format of colon listings, in
+    ;; gnupg/doc/DETAILS)
+    (unless (memq 'disabled (epg-sub-key-capability (car pointer)))
+      (while pointer
+        (if (and (memq usage (epg-sub-key-capability (car pointer)))
+                 (not (memq (epg-sub-key-validity (car pointer))
+                            '(revoked expired))))
+            (setq result t
+                  pointer nil)
+          (setq pointer (cdr pointer)))))
+    result))
+
+(defun mml2015-epg-find-usable-key (context name usage
+                                            &optional name-is-key-id)
+  (let ((keys (epg-list-keys context name))
+        key)
     (while keys
-      (let ((pointer (epg-key-sub-key-list (car keys))))
-        ;; The primary key will be marked as disabled, when the entire
-        ;; key is disabled (see 12 Field, Format of colon listings, in
-        ;; gnupg/doc/DETAILS)
-        (unless (memq 'disabled (epg-sub-key-capability (car pointer)))
-          (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)))))
+      (if (and (or name-is-key-id
+                   ;; Non email user-id can be supplied through
+                   ;; mml2015-signers if mml2015-encrypt-to-self is set.
+                   ;; Treat it as valid, as it is user's intention.
+                   (not (string-match "\\`<" name))
+                   (mml2015-epg-check-user-id (car keys) name))
+               (mml2015-epg-check-sub-key (car keys) usage))
+          (setq key (car keys)
+                keys nil)
+        (setq keys (cdr keys))))
+    key))
 
 ;; XXX: since gpg --list-secret-keys does not return validity of each
 ;; key, `mml2015-epg-find-usable-key' defined above is not enough for
@@ -811,10 +846,12 @@ If set, it overrides the setting of `mml2015-sign-with-sender'."
         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)
+           context
+           (epg-sub-key-fingerprint
+            (car (epg-key-sub-key-list
+                  (car secret-keys))))
+           usage
+           t)
           (setq secret-key (car secret-keys)
                 secret-keys nil)
         (setq secret-keys (cdr secret-keys))))
@@ -1115,8 +1152,7 @@ If no one is selected, symmetric encryption will be performed.  "
                     (mapcar
                      (lambda (recipient)
                        (setq recipient-key (mml2015-epg-find-usable-key
-                                            (epg-list-keys context recipient)
-                                            'encrypt))
+                                            context recipient 'encrypt))
                        (unless (or recipient-key
                                    (y-or-n-p
                                     (format "No public key for %s; skip it? "