1 files changed, 79 insertions, 0 deletions
diff --git a/Mailman/Bouncers/DSN.py b/Mailman/Bouncers/DSN.py
new file mode 100644
index 00000000..3e040bef
--- /dev/null
+++ b/Mailman/Bouncers/DSN.py
@@ -0,0 +1,79 @@
+# Copyright (C) 1998,1999,2000,2001,2002 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+"""Parse RFC 1894 (i.e. DSN) bounce formats."""
+
+from email.Iterators import typed_subpart_iterator
+from email.Utils import parseaddr
+from cStringIO import StringIO
+
+
+
+def check(msg):
+    # Iterate over each message/delivery-status subpart
+    addrs = []
+    for part in typed_subpart_iterator(msg, 'message', 'delivery-status'):
+        if not part.is_multipart():
+            # Huh?
+            continue
+        # Each message/delivery-status contains a list of Message objects
+        # which are the header blocks.  Iterate over those too.
+        for msgblock in part.get_payload():
+            # We try to dig out the Original-Recipient (which is optional) and
+            # Final-Recipient (which is mandatory, but may not exactly match
+            # an address on our list).  Some MTA's also use X-Actual-Recipient
+            # as a synonym for Original-Recipient, but some apparently use
+            # that for other purposes :(
+            #
+            # Also grok out Action so we can do something with that too.
+            action = msgblock.get('action', '')
+            # BAW: Should we treat delayed bounces the same?  Yes, because if
+            # the transient problem clears up, they should get unbounced.  The
+            # other problem is what to do about a DSN that has both delayed
+            # and failed actions in multiple header blocks?  We're not
+            # architected to handle that. ;/
+            if action.lower() not in ('failed', 'failure', 'delayed'):
+                # Some non-permanent failure, so ignore this block
+                continue
+            params = []
+            foundp = 0
+            for header in ('original-recipient', 'final-recipient'):
+                for k, v in msgblock.get_params([], header):
+                    if k.lower() == 'rfc822':
+                        foundp = 1
+                    else:
+                        params.append(k)
+                if foundp:
+                    # Note that params should already be unquoted.
+                    addrs.extend(params)
+                    break
+    # Uniquify
+    rtnaddrs = {}
+    for a in addrs:
+        if a is not None:
+            realname, a = parseaddr(a)
+            rtnaddrs[a] = 1
+    return rtnaddrs.keys()
+
+
+
+def process(msg):
+    # The report-type parameter should be "delivery-status", but it seems that
+    # some DSN generating MTAs don't include this on the Content-Type: header,
+    # so let's relax the test a bit.
+    if not msg.is_multipart() or msg.get_subtype() <> 'report':
+        return None
+    return check(msg)