Make rmail-epa-decrypt handle more ways of formatting the message.

* mail/rmail.el (rmail-epa-decrypt): Detect armor with line prefixes.
Check more carefully for mime-part specified character set.
Check for mime-part Content Transfer Encoding.
Notify if no armor found.

2 files changed, 49 insertions, 14 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index dae450a2776..aac6ba5d739 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,10 @@
+2014-11-08  Richard Stallman  <rms@gnu.org>
+
+        * mail/rmail.el (rmail-epa-decrypt): Detect armor with line prefixes.
+        Check more carefully for mime-part specified character set.
+        Check for mime-part Content Transfer Encoding.
+        Notify if no armor found.
+
 2014-11-08  Martin Rudalics  <rudalics@gmx.at>
 
         * faces.el (face-set-after-frame-default): Enable running
diff --git a/lisp/mail/rmail.el b/lisp/mail/rmail.el
index 5f3628b7131..8c43e090d63 100644
--- a/lisp/mail/rmail.el
+++ b/lisp/mail/rmail.el
@@ -4512,11 +4512,11 @@ encoded string (and the same mask) will decode the string."
   ;; change it in one of the calls to `epa-decrypt-region'.
 
   (save-excursion
-    (let (decrypts)
+    (let (decrypts (mime (rmail-mime-message-p)))
       (goto-char (point-min))
 
       ;; Turn off mime processing.
-      (when (and (rmail-mime-message-p)
+      (when (and mime
                  (not (get-text-property (point-min) 'rmail-mime-hidden)))
         (rmail-mime))
 
@@ -4525,10 +4525,19 @@ encoded string (and the same mask) will decode the string."
       (goto-char (point-min))
       (while (re-search-forward "-----BEGIN PGP MESSAGE-----$" nil t)
         (let ((coding-system-for-read coding-system-for-read)
-              armor-start armor-end after-end)
+              (case-fold-search t)
+              unquote
+              armor-start armor-prefix armor-end after-end)
+
           (setq armor-start (match-beginning 0)
-                armor-end (re-search-forward "^-----END PGP MESSAGE-----$"
-                                             nil t))
+                armor-prefix (buffer-substring
+                              (line-beginning-position)
+                              armor-start)
+                armor-end (re-search-forward
+                           (concat "^"
+                                   armor-prefix
+                                   "-----END PGP MESSAGE-----$")
+                           nil t))
           (unless armor-end
             (error "Encryption armor beginning has no matching end"))
           (goto-char armor-start)
@@ -4536,30 +4545,49 @@ encoded string (and the same mask) will decode the string."
           ;; Because epa--find-coding-system-for-mime-charset not autoloaded.
           (require 'epa)
 
-          ;; Use the charset specified in the armor.
-          (unless coding-system-for-read
-            (if (re-search-forward "^Charset: \\(.*\\)" armor-end t)
-                (setq coding-system-for-read
-                      (epa--find-coding-system-for-mime-charset
-                       (intern (downcase (match-string 1)))))))
-
           ;; Advance over this armor.
           (goto-char armor-end)
           (setq after-end (- (point-max) armor-end))
 
+          (when mime
+            (save-excursion
+              (goto-char armor-start)
+              (re-search-backward "^--" nil t)
+              (save-restriction
+                (narrow-to-region (point) armor-start)
+
+                ;; Use the charset specified in the armor.
+                (unless coding-system-for-read
+                  (if (re-search-forward "^Charset: \\(.*\\)" nil t)
+                      (setq coding-system-for-read
+                            (epa--find-coding-system-for-mime-charset
+                             (intern (downcase (match-string 1)))))))
+
+                (goto-char (point-min))
+                (if (re-search-forward "^[ \t]*Content-transfer-encoding[ \t]*:[ \t]*quoted-printable[ \t]*$" nil t)
+                    (setq unquote t)))))
+
+          (when unquote
+            (let ((inhibit-read-only t))
+              (mail-unquote-printable-region armor-start
+                                             (- (point-max) after-end))))
+
           ;; Decrypt it, maybe in place, maybe making new buffer.
           (epa-decrypt-region
-           armor-start armor-end
+           armor-start (- (point-max) after-end)
            ;; Call back this function to prepare the output.
            (lambda ()
              (let ((inhibit-read-only t))
-               (delete-region armor-start armor-end)
+               (delete-region armor-start (- (point-max) after-end))
                (goto-char armor-start)
                (current-buffer))))
 
           (push (list armor-start (- (point-max) after-end))
                 decrypts)))
 
+      (unless decrypts
+        (error "Nothing to decrypt"))
+
       (when (and decrypts (rmail-buffers-swapped-p))
         (when (y-or-n-p "Replace the original message? ")
           (setq decrypts (nreverse decrypts))