Refactor mm-decode and friends to be explicit about when errors happen

* lisp/gnus/mm-decode.el (mm-sec-status):
(mm-sec-error): New functions to handle decryption problems more
explicitly (bug#18393).
(mm-possibly-verify-or-decrypt): Use the `sec-error' data to
determine whether the operation failed or not.

* lisp/gnus/mml-smime.el: Ditto.

* lisp/gnus/mml2015.el: Used throughout.

1 files changed, 18 insertions, 24 deletions

diff --git a/lisp/gnus/mml-smime.el b/lisp/gnus/mml-smime.el
index b2e9b783522..659f2b95289 100644
--- a/lisp/gnus/mml-smime.el
+++ b/lisp/gnus/mml-smime.el
@@ -274,10 +274,9 @@ Whether the passphrase is cached at all is controlled by
       (if (not good-signature)
 	  (progn
 	    ;; we couldn't verify message, fail with openssl output as message
-	    (mm-set-handle-multipart-parameter
-	     mm-security-handle 'gnus-info "Failed")
-	    (mm-set-handle-multipart-parameter
-	     mm-security-handle 'gnus-details
+	    (mm-sec-error
+	     'gnus-info "Failed"
+	     'gnus-details
 	     (concat "OpenSSL failed to verify message integrity:\n"
 		     "-------------------------------------------\n"
 		     openssl-output)))
@@ -290,19 +289,18 @@ Whether the passphrase is cached at all is controlled by
 	    (while (re-search-forward "-----END CERTIFICATE-----" nil t)
 	      (when (smime-pkcs7-email-region (point-min) (point))
 		(setq addresses (append (smime-buffer-as-string-region
-					 (point-min) (point)) addresses)))
+					 (point-min) (point))
+					addresses)))
 	      (delete-region (point-min) (point)))
 	    (setq addresses (mapcar 'downcase addresses))))
-	(if (not (member (downcase (or (mm-handle-multipart-from ctl) "")) addresses))
-	    (mm-set-handle-multipart-parameter
-	     mm-security-handle 'gnus-info "Sender address forged")
+	(if (not (member (downcase (or (mm-handle-multipart-from ctl) ""))
+			 addresses))
+	    (mm-sec-error 'gnus-info "Sender address forged")
 	  (if good-certificate
-	      (mm-set-handle-multipart-parameter
-	       mm-security-handle 'gnus-info "Ok (sender authenticated)")
-	    (mm-set-handle-multipart-parameter
-	     mm-security-handle 'gnus-info "Ok (sender not trusted)")))
-	(mm-set-handle-multipart-parameter
-	 mm-security-handle 'gnus-details
+	      (mm-sec-status 'gnus-info "Ok (sender authenticated)")
+	    (mm-sec-status 'gnus-info "Ok (sender not trusted)")))
+	(mm-sec-status
+	 'gnus-details
 	 (concat "Sender claimed to be: " (mm-handle-multipart-from ctl) "\n"
 		 (if addresses
 		     (concat "Addresses in certificate: "
@@ -411,24 +409,20 @@ Content-Disposition: attachment; filename=smime.p7m
 					   (cdr handle)
 					   "application/x-pkcs7-signature"
 					   nil t)))))
-	(mm-set-handle-multipart-parameter
-	 mm-security-handle 'gnus-info "Corrupted")
+	(mm-sec-error 'gnus-info "Corrupted")
 	(throw 'error handle))
       (setq part (replace-regexp-in-string "\n" "\r\n" part)
 	    context (epg-make-context 'CMS))
       (condition-case error
 	  (setq plain (epg-verify-string context (mm-get-part signature) part))
 	(error
-	 (mm-set-handle-multipart-parameter
-	  mm-security-handle 'gnus-info "Failed")
+	 (mm-sec-error 'gnus-info "Failed")
 	 (if (eq (car error) 'quit)
-	     (mm-set-handle-multipart-parameter
-	      mm-security-handle 'gnus-details "Quit.")
-	   (mm-set-handle-multipart-parameter
-	    mm-security-handle 'gnus-details (format "%S" error)))
+	     (mm-sec-status 'gnus-details "Quit.")
+	   (mm-sec-status 'gnus-details (format "%S" error)))
 	 (throw 'error handle)))
-      (mm-set-handle-multipart-parameter
-       mm-security-handle 'gnus-info
+      (mm-sec-status
+       'gnus-info
        (epg-verify-result-to-string (epg-context-result-for context 'verify)))
       handle)))