bug#67931: [PATCH] Use S/MIME key from content for mail signing via OpenSSL

[Illia Ostapyshyn]

* Bug

mml-smime-openssl-sign always takes the cdar of smime-keys, resulting in
keyfile parameter of the #secure tag being ignored.  Hence, only the
first entry of smime-keys is used, regardless of the mail contents or
sender address.

* Fix

The relevant information (returned from mml-smime-openssl-sign-query) is
already in the cont alist passed to mml-smime-openssl-sign, just use
that instead.

>From 477badfc705c5dd59cfd8a577eab9eaf4a510e0f Mon Sep 17 00:00:00 2001
From: Illia Ostapyshyn <illia@yshyn.com>
Date: Wed, 20 Dec 2023 13:57:28 +0100
Subject: [PATCH] Use S/MIME key from content for mail signing via OpenSSL

* lisp/gnus/mml-smime.el (mml-smime-openssl-sign): Use the key
passed in the cont argument instead of the first smime-keys entry.
---
 lisp/gnus/mml-smime.el | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/lisp/gnus/mml-smime.el b/lisp/gnus/mml-smime.el
index 896c95f8d3e..713b7fe5b68 100644
--- a/lisp/gnus/mml-smime.el
+++ b/lisp/gnus/mml-smime.el
@@ -130,10 +130,7 @@ mml-smime-verify-test
        (funcall func handle ctl))))
 
 (defun mml-smime-openssl-sign (_cont)
-  (when (null smime-keys)
-    (customize-variable 'smime-keys)
-    (error "No S/MIME keys configured, use customize to add your key"))
-  (smime-sign-buffer (cdar smime-keys))
+  (smime-sign-buffer (cdr (assq 'keyfile cont)))
   (goto-char (point-min))
   (while (search-forward "\r\n" nil t)
     (replace-match "\n" t t))
-- 
2.43.0