From mboxrd@z Thu Jan 1 00:00:00 1970 From: Fabian Bergmark Subject: Fwd: UDP encapsulation of SCTP packages Date: Thu, 18 Jul 2013 21:05:48 +0200 Message-ID: References: Mime-Version: 1.0 Content-Type: multipart/mixed; boundary=20cf301b613be46cc004e1cde583 To: netdev@vger.kernel.org Return-path: Received: from mail-ie0-f170.google.com ([209.85.223.170]:44918 "EHLO mail-ie0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933317Ab3GRTFs (ORCPT ); Thu, 18 Jul 2013 15:05:48 -0400 Received: by mail-ie0-f170.google.com with SMTP id e11so7928899iej.1 for ; Thu, 18 Jul 2013 12:05:48 -0700 (PDT) In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: --20cf301b613be46cc004e1cde583 Content-Type: text/plain; charset=ISO-8859-1 Im working on implementing UDP encapsulation of SCTP packages. I have tried to implement the encapsulation/decapsulation in a way that is transparent to the logic of the current implementation. Currently I'am able to send and recieve data over localhost or over intranet. However, when trying to communicate over NAT I ran in to problems. Because of port remapping of the UDP source port I included as a final step to update the source port of the SCTP header and recalculate the checksum. This however, causes a kernel panic somewhere between receiving the UDP packet and replying the INIT_ACK, that I am unable to understand. Is there anything, besides the source port and checksum in the SCTP header that needs to be updated? I have included a packet capture of the INIT-packages that causes the panic. As I am new to kernel development, general advice on how to debug this issue is appreciated. -- Fabian Bergmark --20cf301b613be46cc004e1cde583 Content-Type: application/octet-stream; name="SCTP in UDP.pcap" Content-Disposition: attachment; filename="SCTP in UDP.pcap" Content-Transfer-Encoding: base64 X-Attachment-Id: f_hjab8sgm0 Cg0NCmgAAABNPCsaAQAAAP//////////AwAQAExpbnV4IDMuOS4yLUFSQ0gEAC0ARHVtcGNhcCAx LjEwLjAgKFNWTiBSZXYgVW5rbm93biBmcm9tIHVua25vd24pAAAAAAAAAGgAAAABAAAARAAAAAEA AAD//wAAAgAEAGV0aDAJAAEABgAAAAsABAAAdWRwDAAQAExpbnV4IDMuOS4yLUFSQ0gAAAAARAAA AAYAAAB8AAAAAAAAAM3hBACn17keWgAAAFoAAABSVADWNxQIACfYt8kIAEUCAEwAAEAAQBF3d1Ox p1fAqAd30tEFOAA4tHzS0QU5AAAAAHTqW3sBAAAk8jfPSgABoAAAAgACjfjWmQAMAAYABQAAgAAA BMAAAAQAAHwAAAAGAAAAfAAAAAAAAADN4QQAS6LnHloAAABaAAAAUlQA1jcUCAAn2LfJCABFAgBM AABAAEARd3dTsadXwKgHd9LRBTgAOLR80tEFOQAAAAB06lt7AQAAJPI3z0oAAaAAAAIAAo341pkA DAAGAAUAAIAAAATAAAAEAAB8AAAABQAAAGwAAAAAAAAAzeEEAGMAmR8BABwAQ291bnRlcnMgcHJv dmlkZWQgYnkgZHVtcGNhcAIACADN4QQA4LhsHgMACADN4QQAmf+YHwQACAAHAAAAAAAAAAUACAAA AAAAAAAAAAAAAABsAAAA --20cf301b613be46cc004e1cde583--