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diff --git a/lisp/international/textsec-check.el b/lisp/international/textsec-check.el
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+;;; textsec-check.el --- Check for suspicious texts  -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2022 Free Software Foundation, Inc.
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; GNU Emacs is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;;
+
+;;; Code:
+
+(defgroup textsec nil
+  "Suspicious text identification."
+  :group 'security
+  :version "29.1")
+
+(defcustom textsec-check t
+  "If non-nil, perform some security-related checks on text objects.
+If nil, these checks are disabled."
+  :type 'boolean
+  :version "29.1")
+
+(defface textsec-suspicious
+  '((t (:weight bold :background "red")))
+  "Face used to highlight suspicious strings.")
+
+;;;###autoload
+(defun textsec-suspicious-p (object type)
+  "Say whether OBJECT is suspicious for use as TYPE.
+If OBJECT is suspicious, return a string explaining the reason
+for considering it suspicious, otherwise return nil.
+
+Available values of TYPE and corresponding OBJECTs are:
+
+ `url'                   -- a URL; OBJECT should be a URL string.
+
+ `link'                 -- an HTML link; OBJECT should be a cons cell
+                           of the form (URL . LINK-TEXT).
+
+ `domain'               -- a Web domain; OBJECT should be a string.
+
+ `local-address'        -- the local part of an email address; OBJECT
+                           should be a string.
+ `name'                 -- the \"display name\" part of an email address;
+                           OBJECT should be a string.
+
+`email-address'         -- a full email address; OBJECT should be a string.
+
+ `email-address-header' -- a raw email address header in RFC 2822 format;
+                           OBJECT should be a string.
+
+If the user option `textsec-check' is nil, these checks are
+disabled, and this function always returns nil."
+  (if (not textsec-check)
+      nil
+    (require 'textsec)
+    (let ((func (intern (format "textsec-%s-suspicious-p" type))))
+      (unless (fboundp func)
+        (error "%s is not a valid function" func))
+      (funcall func object))))
+
+(provide 'textsec-check)
+
+;;; textsec-check.el ends here