From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753756AbdBVDEC (ORCPT ); Tue, 21 Feb 2017 22:04:02 -0500 Received: from mail-qk0-f195.google.com ([209.85.220.195]:36278 "EHLO mail-qk0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752850AbdBVDD4 (ORCPT ); Tue, 21 Feb 2017 22:03:56 -0500 MIME-Version: 1.0 In-Reply-To: References: <20170106123711.GA15139@hmsreliant.think-freely.org> <063D6719AE5E284EB5DD2968C1650D6DB025A97E@AcuExch.aculab.com> <20170109122408.GA20973@hmswarspite.think-freely.org> <20170109191823.GC20973@hmswarspite.think-freely.org> <20170110143351.GA10195@hmswarspite.think-freely.org> <20170111125708.GA1518@hmswarspite.think-freely.org> <063D6719AE5E284EB5DD2968C1650D6DB025F9FD@AcuExch.aculab.com> <4163FC71-3A20-4484-8CDC-FA22D4FA72CF@lurchi.franken.de> <15C09FCB-B635-4144-84FA-E699A9C684CA@lurchi.franken.de> <10F99ED9-3820-4D7B-8AB8-B520741247C5@lurchi.franken.de> From: Xin Long Date: Wed, 22 Feb 2017 11:03:53 +0800 Message-ID: Subject: Re: Problem on SCTP To: Sun Paul Cc: Michael Tuexen , David Laight , Neil Horman , "linux-sctp@vger.kernel.org" , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 22, 2017 at 10:29 AM, Sun Paul wrote: > Hi Xin > > do you mean we need to patch the kernel? Yups, pls comment on that bz if it's really needed for your env. A z-stream kernel may be available for that issue soon. Thanks. > > > > On Wed, Feb 22, 2017 at 10:00 AM, Xin Long wrote: >> On Wed, Feb 22, 2017 at 9:12 AM, Sun Paul wrote: >>> Hi >>> >>> the router is actually is a linux running on RHEL6.8 >>> (2.6.32-642.4.2.el6.x86_64). it uses iptables to do SNAT aand DNAT >>> forward. >> https://bugzilla.redhat.com/show_bug.cgi?id=1412038 >> >> sctp_manip_pkt->sctp_compute_cksum: >> struct sctphdr *sh = sctp_hdr(sub); >> >> But in rhel6, skb->transport_header is not yet set at that time. >> This patch should be backported into rhel6. >> >> commit 21d1196a35f5686c4323e42a62fdb4b23b0ab4a3 >> Author: Eric Dumazet >> Date: Mon Jul 15 20:03:19 2013 -0700 >> >> ipv4: set transport header earlier >> >> >>> >>> On Tue, Feb 21, 2017 at 11:53 PM, Xin Long wrote: >>>> On Tue, Feb 21, 2017 at 12:26 PM, Sun Paul wrote: >>>>> Hi, >>>>> >>>>> sorry to get back late, the platform is running on KVM. and this >>>>> problem is resolved by moving to VMware environment, however, a new >>>>> problem is coming out, we noticed that the HB REQ is being ABORT from >>>>> client. >>>>> >>>>> >>>>> 03:32:35.233572 IP 10.165.250.22.3868 > 192.168.2.13.40001: sctp (1) >>>>> [HB REQ] (from server to sctp router) >>>>> 03:32:35.233603 IP 192.168.2.14.3868 > 192.168.2.13.40001: sctp (1) >>>>> [HB REQ] (from sctp router to client) >>>>> 03:32:35.233852 IP 192.168.2.13.40001 > 192.168.2.14.3868: sctp (1) >>>>> [ABORT] (from client to sctp router) >>>>> >>>>> 03:32:37.928679 IP 10.165.250.22.3868 > 192.168.2.13.40001: sctp (1) [HB REQ] >>>>> 03:32:37.928717 IP 192.168.2.14.3868 > 192.168.2.13.40001: sctp (1) [HB REQ] >>>>> 03:32:37.929247 IP 192.168.2.13.40001 > 192.168.2.14.3868: sctp (1) [ABORT] >>>>> >>>>> For the above packet flow, 10.165.250.22 is the server and >>>>> 192.168.2.13 is the client, the server 10.165.250.22 sends HB REQ to >>>>> client 192.168.2.13 through 192.168.2.14 (the SCTP router), and the >>>>> SCTP router change the src address before forward the HB REQ to the >>>>> client. >>>>> >>>>> But somehow the client is ABORT the HB REQ, any idea? is it related to >>>>> the HEARTBEAT information? or the checksum again>? >>>> The incorrect checksum won't cause ABORT, but the abnormal HB REQ >>>> could be, if HB information was modified when calculating the checksum >>>> on router, the ABORT may be caused in client process. >>>> >>>> is your SCTP router linux ? if yes, what's the kernel version ? >>>> >>>>> >>>>> On Fri, Jan 13, 2017 at 9:19 PM, Michael Tuexen >>>>> wrote: >>>>>>> On 13 Jan 2017, at 10:43, Michael Tuexen wrote: >>>>>>> >>>>>>> Your router does NOT change any field in the SCTP packet, but the >>>>>>> SCTP checksum was modified from >>>>>>> Checksum: 0xbaea49e5 (not verified) >>>>>>> to >>>>>>> Checksum: 0xa9a86d3f (not verified) >>>>>>> At least one of these is wrong. Read the tracefiles in wireshark and >>>>>>> enable checksum validation and wireshark will tell you which one is >>>>>>> correct. (That is why I asked for .pcap file instead of a .txt). >>>>>>> >>>>>>> My guess is that the initial checksum is correct and your box middlebox >>>>>>> not only changes the destination address and ttl field and header >>>>>>> checksum in the IP-header (which is expected) but also incorrectly the >>>>>>> SCTP checksum. Since no field in the SCTP packet has changed, the checksum >>>>>>> must be the same. >>>>>> At the server have a look at the SNMP counters: >>>>>> cat /proc/net/sctp/snmp >>>>>> You should find a line staring with >>>>>> SctpChecksumErrors >>>>>> If the number reported there is positive, the node received packets >>>>>> with checksum errors. >>>>>> >>>>>> Best regards >>>>>> Michael >>>>>>> >>>>>>> Best regards >>>>>>> Michael >>>>>>>> On 13 Jan 2017, at 04:29, Sun Paul wrote: >>>>>>>> >>>>>>>> Frame 2: 98 bytes on wire (784 bits), 98 bytes captured (784 bits) >>>>>>>> Encapsulation type: Ethernet (1) >>>>>>>> Arrival Time: Jan 6, 2017 16:52:49.662321000 Malay Peninsula Standard Time >>>>>>>> [Time shift for this packet: 0.000000000 seconds] >>>>>>>> Epoch Time: 1483692769.662321000 seconds >>>>>>>> [Time delta from previous captured frame: 0.000179000 seconds] >>>>>>>> [Time delta from previous displayed frame: 0.000179000 seconds] >>>>>>>> [Time since reference or first frame: 0.000179000 seconds] >>>>>>>> Frame Number: 2 >>>>>>>> Frame Length: 98 bytes (784 bits) >>>>>>>> Capture Length: 98 bytes (784 bits) >>>>>>>> [Frame is marked: False] >>>>>>>> [Frame is ignored: False] >>>>>>>> [Protocols in frame: eth:ethertype:ip:sctp] >>>>>>>> Ethernet II, Src: Vmware_81:41:6b (00:50:56:81:41:6b), Dst: >>>>>>>> Vmware_81:a6:a3 (00:50:56:81:a6:a3) >>>>>>>> Destination: Vmware_81:a6:a3 (00:50:56:81:a6:a3) >>>>>>>> Address: Vmware_81:a6:a3 (00:50:56:81:a6:a3) >>>>>>>> .... ..0. .... .... .... .... = LG bit: Globally unique >>>>>>>> address (factory default) >>>>>>>> .... ...0 .... .... .... .... = IG bit: Individual address (unicast) >>>>>>>> Source: Vmware_81:41:6b (00:50:56:81:41:6b) >>>>>>>> Address: Vmware_81:41:6b (00:50:56:81:41:6b) >>>>>>>> .... ..0. .... .... .... .... = LG bit: Globally unique >>>>>>>> address (factory default) >>>>>>>> .... ...0 .... .... .... .... = IG bit: Individual address (unicast) >>>>>>>> Type: IPv4 (0x0800) >>>>>>>> Internet Protocol Version 4, Src: 192.168.206.83, Dst: 192.168.206.66 >>>>>>>> 0100 .... = Version: 4 >>>>>>>> .... 0101 = Header Length: 20 bytes (5) >>>>>>>> Differentiated Services Field: 0x02 (DSCP: CS0, ECN: ECT(0)) >>>>>>>> 0000 00.. = Differentiated Services Codepoint: Default (0) >>>>>>>> .... ..10 = Explicit Congestion Notification: ECN-Capable >>>>>>>> Transport codepoint '10' (2) >>>>>>>> Total Length: 84 >>>>>>>> Identification: 0x0000 (0) >>>>>>>> Flags: 0x02 (Don't Fragment) >>>>>>>> 0... .... = Reserved bit: Not set >>>>>>>> .1.. .... = Don't fragment: Set >>>>>>>> ..0. .... = More fragments: Not set >>>>>>>> Fragment offset: 0 >>>>>>>> Time to live: 63 >>>>>>>> Protocol: SCTP (132) >>>>>>>> Header checksum: 0x1d3d [validation disabled] >>>>>>>> [Good: False] >>>>>>>> [Bad: False] >>>>>>>> Source: 192.168.206.83 >>>>>>>> Destination: 192.168.206.66 >>>>>>>> [Source GeoIP: Unknown] >>>>>>>> [Destination GeoIP: Unknown] >>>>>>>> Stream Control Transmission Protocol, Src Port: 50001 (50001), Dst >>>>>>>> Port: 3868 (3868) >>>>>>>> Source port: 50001 >>>>>>>> Destination port: 3868 >>>>>>>> Verification tag: 0x00000000 >>>>>>>> [Assocation index: 0] >>>>>>>> Checksum: 0xa9a86d3f (not verified) >>>>>>>> >>>>>>>> INIT chunk (Outbound streams: 3000, inbound streams: 3000) >>>>>>>> Chunk type: INIT (1) >>>>>>>> 0... .... = Bit: Stop processing of the packet >>>>>>>> .0.. .... = Bit: Do not report >>>>>>>> Chunk flags: 0x00 >>>>>>>> Chunk length: 52 >>>>>>>> Initiate tag: 0xe79f40cb >>>>>>>> Advertised receiver window credit (a_rwnd): 62464 >>>>>>>> Number of outbound streams: 3000 >>>>>>>> Number of inbound streams: 3000 >>>>>>>> Initial TSN: 176990880 >>>>>>>> IPv4 address parameter (Address: 192.168.206.83) >>>>>>>> Parameter type: IPv4 address (0x0005) >>>>>>>> 0... .... .... .... = Bit: Stop processing of chunk >>>>>>>> .0.. .... .... .... = Bit: Do not report >>>>>>>> Parameter length: 8 >>>>>>>> IP Version 4 address: 192.168.206.83 >>>>>>>> IPv4 address parameter (Address: 192.168.1.83) >>>>>>>> Parameter type: IPv4 address (0x0005) >>>>>>>> 0... .... .... .... = Bit: Stop processing of chunk >>>>>>>> .0.. .... .... .... = Bit: Do not report >>>>>>>> Parameter length: 8 >>>>>>>> IP Version 4 address: 192.168.1.83 >>>>>>>> Supported address types parameter (Supported types: IPv6, IPv4) >>>>>>>> Parameter type: Supported address types (0x000c) >>>>>>>> 0... .... .... .... = Bit: Stop processing of chunk >>>>>>>> .0.. .... .... .... = Bit: Do not report >>>>>>>> Parameter length: 8 >>>>>>>> Supported address type: IPv6 address (6) >>>>>>>> Supported address type: IPv4 address (5) >>>>>>>> ECN parameter >>>>>>>> Parameter type: ECN (0x8000) >>>>>>>> 1... .... .... .... = Bit: Skip parameter and continue >>>>>>>> processing of the chunk >>>>>>>> .0.. .... .... .... = Bit: Do not report >>>>>>>> Parameter length: 4 >>>>>>>> Forward TSN supported parameter >>>>>>>> Parameter type: Forward TSN supported (0xc000) >>>>>>>> 1... .... .... .... = Bit: Skip parameter and continue >>>>>>>> processing of the chunk >>>>>>>> .1.. .... .... .... = Bit: Do report >>>>>>>> Parameter length: 4 >>>>>>> >>>>>>> -- >>>>>>> To unsubscribe from this list: send the line "unsubscribe linux-sctp" in >>>>>>> the body of a message to majordomo@vger.kernel.org >>>>>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>>>>> >>>>> -- >>>>> To unsubscribe from this list: send the line "unsubscribe linux-sctp" in >>>>> the body of a message to majordomo@vger.kernel.org >>>>> More majordomo info at http://vger.kernel.org/majordomo-info.html