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diff --git a/mailman/web/Gui/ContentFilter.py b/mailman/web/Gui/ContentFilter.py
new file mode 100644
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+++ b/mailman/web/Gui/ContentFilter.py
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+# Copyright (C) 2002-2008 by the Free Software Foundation, Inc.
+#
+# This file is part of GNU Mailman.
+#
+# GNU Mailman 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 Mailman 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 Mailman.  If not, see <http://www.gnu.org/licenses/>.
+
+"""GUI component managing the content filtering options."""
+
+from Mailman.Gui.GUIBase import GUIBase
+from Mailman.configuration import config
+from Mailman.i18n import _
+
+NL = '\n'
+
+
+
+class ContentFilter(GUIBase):
+    def GetConfigCategory(self):
+        return 'contentfilter', _('Content&nbsp;filtering')
+
+    def GetConfigInfo(self, mlist, category, subcat=None):
+        if category <> 'contentfilter':
+            return None
+        WIDTH = config.TEXTFIELDWIDTH
+
+        actions = [_('Discard'), _('Reject'), _('Forward to List Owner')]
+        if config.OWNERS_CAN_PRESERVE_FILTERED_MESSAGES:
+            actions.append(_('Preserve'))
+
+        return [
+            _("""Policies concerning the content of list traffic.
+
+            <p>Content filtering works like this: when a message is
+            received by the list and you have enabled content filtering, the
+            individual attachments are first compared to the
+            <a href="?VARHELP=contentfilter/filter_mime_types">filter
+            types</a>.  If the attachment type matches an entry in the filter
+            types, it is discarded.
+
+            <p>Then, if there are <a
+            href="?VARHELP=contentfilter/pass_mime_types">pass types</a>
+            defined, any attachment type that does <em>not</em> match a
+            pass type is also discarded.  If there are no pass types defined,
+            this check is skipped.
+
+            <p>After this initial filtering, any <tt>multipart</tt>
+            attachments that are empty are removed.  If the outer message is
+            left empty after this filtering, then the whole message is
+            discarded.
+
+            <p> Then, each <tt>multipart/alternative</tt> section will
+            be replaced by just the first alternative that is non-empty after
+            filtering if
+            <a href="?VARHELP=contentfilter/collapse_alternatives"
+            >collapse_alternatives</a> is enabled.
+
+            <p>Finally, any <tt>text/html</tt> parts that are left in the
+            message may be converted to <tt>text/plain</tt> if
+            <a href="?VARHELP=contentfilter/convert_html_to_plaintext"
+            >convert_html_to_plaintext</a> is enabled and the site is
+            configured to allow these conversions."""),
+
+            ('filter_content', config.Radio, (_('No'), _('Yes')), 0,
+             _("""Should Mailman filter the content of list traffic according
+             to the settings below?""")),
+
+            ('filter_mime_types', config.Text, (10, WIDTH), 0,
+             _("""Remove message attachments that have a matching content
+             type."""),
+
+             _("""Use this option to remove each message attachment that
+             matches one of these content types.  Each line should contain a
+             string naming a MIME <tt>type/subtype</tt>,
+             e.g. <tt>image/gif</tt>.  Leave off the subtype to remove all
+             parts with a matching major content type, e.g. <tt>image</tt>.
+
+             <p>Blank lines are ignored.
+
+             <p>See also <a href="?VARHELP=contentfilter/pass_mime_types"
+             >pass_mime_types</a> for a content type whitelist.""")),
+
+            ('pass_mime_types', config.Text, (10, WIDTH), 0,
+             _("""Remove message attachments that don't have a matching
+             content type.  Leave this field blank to skip this filter
+             test."""),
+
+             _("""Use this option to remove each message attachment that does
+             not have a matching content type.  Requirements and formats are
+             exactly like <a href="?VARHELP=contentfilter/filter_mime_types"
+             >filter_mime_types</a>.
+
+             <p><b>Note:</b> if you add entries to this list but don't add
+             <tt>multipart</tt> to this list, any messages with attachments
+             will be rejected by the pass filter.""")),
+
+            ('filter_filename_extensions', config.Text, (10, WIDTH), 0,
+             _("""Remove message attachments that have a matching filename
+             extension."""),),
+
+            ('pass_filename_extensions', config.Text, (10, WIDTH), 0,
+             _("""Remove message attachments that don't have a matching
+             filename extension.  Leave this field blank to skip this filter
+             test."""),),
+
+            ('collapse_alternatives', config.Radio, (_('No'), _('Yes')), 0,
+             _("""Should Mailman collapse multipart/alternative to its
+             first part content?""")),
+
+            ('convert_html_to_plaintext', config.Radio, (_('No'), _('Yes')), 0,
+             _("""Should Mailman convert <tt>text/html</tt> parts to plain
+             text?  This conversion happens after MIME attachments have been
+             stripped.""")),
+
+            ('filter_action', config.Radio, tuple(actions), 0,
+
+             _("""Action to take when a message matches the content filtering
+             rules."""),
+
+             _("""One of these actions is take when the message matches one of
+             the content filtering rules, meaning, the top-level
+             content type matches one of the <a
+             href="?VARHELP=contentfilter/filter_mime_types"
+             >filter_mime_types</a>, or the top-level content type does
+             <strong>not</strong> match one of the
+             <a href="?VARHELP=contentfilter/pass_mime_types"
+             >pass_mime_types</a>, or if after filtering the subparts of the
+             message, the message ends up empty.
+
+             <p>Note this action is not taken if after filtering the message
+             still contains content.  In that case the message is always
+             forwarded on to the list membership.
+
+             <p>When messages are discarded, a log entry is written
+             containing the Message-ID of the discarded message.  When
+             messages are rejected or forwarded to the list owner, a reason
+             for the rejection is included in the bounce message to the
+             original author.  When messages are preserved, they are saved in
+             a special queue directory on disk for the site administrator to
+             view (and possibly rescue) but otherwise discarded.  This last
+             option is only available if enabled by the site
+             administrator.""")),
+            ]
+
+    def _setValue(self, mlist, property, val, doc):
+        if property in ('filter_mime_types', 'pass_mime_types'):
+            types = []
+            for spectype in [s.strip() for s in val.splitlines()]:
+                ok = 1
+                slashes = spectype.count('/')
+                if slashes == 0 and not spectype:
+                    ok = 0
+                elif slashes == 1:
+                    maintype, subtype = [s.strip().lower()
+                                         for s in spectype.split('/')]
+                    if not maintype or not subtype:
+                        ok = 0
+                elif slashes > 1:
+                    ok = 0
+                if not ok:
+                    doc.addError(_('Bad MIME type ignored: %(spectype)s'))
+                else:
+                    types.append(spectype.strip().lower())
+            if property == 'filter_mime_types':
+                mlist.filter_mime_types = types
+            elif property == 'pass_mime_types':
+                mlist.pass_mime_types = types
+        elif property in ('filter_filename_extensions',
+                          'pass_filename_extensions'):
+            fexts = []
+            for ext in [s.strip() for s in val.splitlines()]:
+                fexts.append(ext.lower())
+            if property == 'filter_filename_extensions':
+                mlist.filter_filename_extensions = fexts
+            elif property == 'pass_filename_extensions':
+                mlist.pass_filename_extensions = fexts
+        else:
+            GUIBase._setValue(self, mlist, property, val, doc)
+
+    def getValue(self, mlist, kind, property, params):
+        if property == 'filter_mime_types':
+            return NL.join(mlist.filter_mime_types)
+        if property == 'pass_mime_types':
+            return NL.join(mlist.pass_mime_types)
+        if property == 'filter_filename_extensions':
+            return NL.join(mlist.filter_filename_extensions)
+        if property == 'pass_filename_extensions':
+            return NL.join(mlist.pass_filename_extensions)
+        return None