1 files changed, 117 insertions, 0 deletions
diff --git a/mailman/rules/approved.py b/mailman/rules/approved.py
new file mode 100644
index 000000000..be8ceaab7
--- /dev/null
+++ b/mailman/rules/approved.py
@@ -0,0 +1,117 @@
+# Copyright (C) 2007-2008 by the Free Software Foundation, Inc.
+#
+# This program 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 2
+# of the License, or (at your option) any later version.
+#
+# This program 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 this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+# USA.
+
+"""Look for moderator pre-approval."""
+
+__all__ = ['Approved']
+__metaclass__ = type
+
+
+import re
+from email.iterators import typed_subpart_iterator
+from zope.interface import implements
+
+from mailman.i18n import _
+from mailman.interfaces import IRule
+
+
+EMPTYSTRING = u''
+
+
+
+class Approved:
+    """Look for moderator pre-approval."""
+    implements(IRule)
+
+    name = 'approved'
+    description = _('The message has a matching Approve or Approved header.')
+    record = True
+
+    def check(self, mlist, msg, msgdata):
+        """See `IRule`."""
+        # See if the message has an Approved or Approve header with a valid
+        # moderator password.  Also look at the first non-whitespace line in
+        # the file to see if it looks like an Approved header.
+        missing = object()
+        password = msg.get('approved', msg.get('approve', missing))
+        if password is missing:
+            # Find the first text/plain part in the message
+            part = None
+            stripped = False
+            for part in typed_subpart_iterator(msg, 'text', 'plain'):
+                break
+            payload = part.get_payload(decode=True)
+            if payload is not None:
+                lines = payload.splitlines(True)
+                for lineno, line in enumerate(lines):
+                    if line.strip() <> '':
+                        break
+                if ':' in line:
+                    header, value = line.split(':', 1)
+                    if header.lower() in ('approved', 'approve'):
+                        password = value.strip()
+                        # Now strip the first line from the payload so the
+                        # password doesn't leak.
+                        del lines[lineno]
+                        reset_payload(part, EMPTYSTRING.join(lines))
+                        stripped = True
+            if stripped:
+                # Now try all the text parts in case it's
+                # multipart/alternative with the approved line in HTML or
+                # other text part.  We make a pattern from the Approved line
+                # and delete it from all text/* parts in which we find it.  It
+                # would be better to just iterate forward, but email
+                # compatability for pre Python 2.2 returns a list, not a true
+                # iterator.
+                #
+                # This will process all the multipart/alternative parts in the
+                # message as well as all other text parts.  We shouldn't find
+                # the pattern outside the multipart/alternative parts, but if
+                # we do, it is probably best to delete it anyway as it does
+                # contain the password.
+                #
+                # Make a pattern to delete.  We can't just delete a line
+                # because line of HTML or other fancy text may include
+                # additional message text.  This pattern works with HTML.  It
+                # may not work with rtf or whatever else is possible.
+                pattern = header + ':(\s|&nbsp;)*' + re.escape(password)
+                for part in typed_subpart_iterator(msg, 'text'):
+                    payload = part.get_payload(decode=True)
+                    if payload is not None:
+                        if re.search(pattern, payload):
+                            reset_payload(part, re.sub(pattern, '', payload))
+        else:
+            del msg['approved']
+            del msg['approve']
+        return password is not missing and password == mlist.moderator_password
+
+
+
+def reset_payload(part, payload):
+    # Set decoded payload maintaining content-type, charset, format and delsp.
+    charset = part.get_content_charset() or 'us-ascii'
+    content_type = part.get_content_type()
+    format = part.get_param('format')
+    delsp = part.get_param('delsp')
+    del part['content-transfer-encoding']
+    del part['content-type']
+    part.set_payload(payload, charset)
+    part.set_type(content_type)
+    if format:
+        part.set_param('Format', format)
+    if delsp:
+        part.set_param('DelSp', delsp)