From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gui Jianfeng Subject: Re: [PATCH] SCTP: Fix Protocol violation when receiving a error length INIT ACK Date: Thu, 27 Mar 2008 09:40:34 +0800 Message-ID: <47EAFB12.9040800@cn.fujitsu.com> References: <47E73E83.9000301@cn.fujitsu.com> <47E74B17.40907@cn.fujitsu.com> <47E87290.2080205@cn.fujitsu.com> <47E883B9.5040907@cn.fujitsu.com> <47E8A566.6060405@cn.fujitsu.com> <47E915E3.2040501@hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Wei Yongjun , netdev , lksctp-dev , David Miller To: Vlad Yasevich Return-path: Received: from cn.fujitsu.com ([222.73.24.84]:60380 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1754615AbYC0BlU (ORCPT ); Wed, 26 Mar 2008 21:41:20 -0400 In-Reply-To: <47E915E3.2040501@hp.com> Sender: netdev-owner@vger.kernel.org List-ID: Vlad Yasevich wrote: > There is a side-effect to this patch that now we will completely ignore > the verification > tag in the INIT-ACK regardless of the violation. > > In particular, if the INIT-ACK contains all the fixed parameters but > violates structure > in some variable parameters, we'll currently use the Initiate Tag from > the INIT-ACK in > the ABORT. We should not be changing this behavior. > > The simple hack is to add some conditional code into the the different > violation functions, but > I'd like to see if there is a cleaner way to solve this. Vlad, The problem you said has been addressed, this is a new patch. Just treat an INIT-ACK received during COOKIE-WAIT as a special case. this patch will not break the normal behavior. Signed-off-by: Gui Jianfeng --- include/net/sctp/command.h | 1 + net/sctp/outqueue.c | 3 +++ net/sctp/sm_sideeffect.c | 5 ++++- net/sctp/sm_statefuns.c | 18 ++++++++++++++++++ 4 files changed, 26 insertions(+), 1 deletions(-) diff --git a/include/net/sctp/command.h b/include/net/sctp/command.h index 10ae2da..35b1e83 100644 --- a/include/net/sctp/command.h +++ b/include/net/sctp/command.h @@ -104,6 +104,7 @@ typedef enum { SCTP_CMD_ADAPTATION_IND, /* generate and send adaptation event */ SCTP_CMD_ASSOC_SHKEY, /* generate the association shared keys */ SCTP_CMD_T1_RETRAN, /* Mark for retransmission after T1 timeout */ + SCTP_CMD_UPDATE_INITTAG, /* Update peer inittag */ SCTP_CMD_LAST } sctp_verb_t; diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c index 1bb3c5c..c071446 100644 --- a/net/sctp/outqueue.c +++ b/net/sctp/outqueue.c @@ -793,6 +793,9 @@ int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout) break; case SCTP_CID_ABORT: + if (sctp_test_T_bit(chunk)) { + packet->vtag = asoc->c.my_vtag; + } case SCTP_CID_SACK: case SCTP_CID_HEARTBEAT: case SCTP_CID_HEARTBEAT_ACK: diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c index 28eb38e..2dbc7bd 100644 --- a/net/sctp/sm_sideeffect.c +++ b/net/sctp/sm_sideeffect.c @@ -1536,7 +1536,10 @@ static int sctp_cmd_interpreter(sctp_event_t event_type, error = sctp_auth_asoc_init_active_key(asoc, GFP_ATOMIC); break; - + case SCTP_CMD_UPDATE_INITTAG: + asoc->peer.i.init_tag = cmd->obj.u32; + break; + default: printk(KERN_WARNING "Impossible command: %u, %p\n", cmd->verb, cmd->obj.ptr); diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index f2ed647..b3ed52c 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -4144,6 +4144,24 @@ static sctp_disposition_t sctp_sf_abort_violation( goto nomem; if (asoc) { + /* Treat INIT-ACK as a special case during COOKIE-WAIT. */ + if (chunk->chunk_hdr->type == SCTP_CID_INIT_ACK + && !asoc->peer.i.init_tag) { + sctp_initack_chunk_t *initack; + + initack = (sctp_initack_chunk_t *)chunk->chunk_hdr; + if (!sctp_chunk_length_valid(chunk, + sizeof(sctp_initack_chunk_t))) + abort->chunk_hdr->flags |= SCTP_CHUNK_FLAG_T; + else { + unsigned int inittag; + + inittag = ntohl(initack->init_hdr.init_tag); + sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_INITTAG, + SCTP_U32(inittag)); + } + } + sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); -- 1.5.3 -- Regards Gui Jianfeng