From ef75d49f116bccbb80bccd423ecf3cb86c4509a5 Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Thu, 8 May 2008 01:15:21 -0700 Subject: [PATCH] netfilter: nf_conntrack_sip: restrict RTP expect flushing on error to last request Some Inovaphone PBXs exhibit very stange behaviour: when dialing for example "123", the device sends INVITE requests for "1", "12" and "123" back to back. The first requests will elicit error responses from the receiver, causing the SIP helper to flush the RTP expectations even though we might still see a positive response. Note the sequence number of the last INVITE request that contained a media description and only flush the expectations when receiving a negative response for that sequence number. Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- include/linux/netfilter/nf_conntrack_sip.h | 1 + net/netfilter/nf_conntrack_sip.c | 22 +++++++++++++--------- 2 files changed, 14 insertions(+), 9 deletions(-) diff --git a/include/linux/netfilter/nf_conntrack_sip.h b/include/linux/netfilter/nf_conntrack_sip.h index 5da04e586a..23aa2ec6b7 100644 --- a/include/linux/netfilter/nf_conntrack_sip.h +++ b/include/linux/netfilter/nf_conntrack_sip.h @@ -7,6 +7,7 @@ struct nf_ct_sip_master { unsigned int register_cseq; + unsigned int invite_cseq; }; enum sip_expectation_classes { diff --git a/net/netfilter/nf_conntrack_sip.c b/net/netfilter/nf_conntrack_sip.c index 9f49000695..2f9bbc058b 100644 --- a/net/netfilter/nf_conntrack_sip.c +++ b/net/netfilter/nf_conntrack_sip.c @@ -870,6 +870,7 @@ static int process_sdp(struct sk_buff *skb, { enum ip_conntrack_info ctinfo; struct nf_conn *ct = nf_ct_get(skb, &ctinfo); + struct nf_conn_help *help = nfct_help(ct); unsigned int matchoff, matchlen; unsigned int mediaoff, medialen; unsigned int sdpoff; @@ -959,6 +960,9 @@ static int process_sdp(struct sk_buff *skb, if (nf_nat_sdp_session && ct->status & IPS_NAT_MASK) ret = nf_nat_sdp_session(skb, dptr, sdpoff, datalen, &rtp_addr); + if (ret == NF_ACCEPT && i > 0) + help->help.ct_sip_info.invite_cseq = cseq; + return ret; } static int process_invite_response(struct sk_buff *skb, @@ -967,14 +971,14 @@ static int process_invite_response(struct sk_buff *skb, { enum ip_conntrack_info ctinfo; struct nf_conn *ct = nf_ct_get(skb, &ctinfo); + struct nf_conn_help *help = nfct_help(ct); if ((code >= 100 && code <= 199) || (code >= 200 && code <= 299)) return process_sdp(skb, dptr, datalen, cseq); - else { + else if (help->help.ct_sip_info.invite_cseq == cseq) flush_expectations(ct, true); - return NF_ACCEPT; - } + return NF_ACCEPT; } static int process_update_response(struct sk_buff *skb, @@ -983,14 +987,14 @@ static int process_update_response(struct sk_buff *skb, { enum ip_conntrack_info ctinfo; struct nf_conn *ct = nf_ct_get(skb, &ctinfo); + struct nf_conn_help *help = nfct_help(ct); if ((code >= 100 && code <= 199) || (code >= 200 && code <= 299)) return process_sdp(skb, dptr, datalen, cseq); - else { + else if (help->help.ct_sip_info.invite_cseq == cseq) flush_expectations(ct, true); - return NF_ACCEPT; - } + return NF_ACCEPT; } static int process_prack_response(struct sk_buff *skb, @@ -999,14 +1003,14 @@ static int process_prack_response(struct sk_buff *skb, { enum ip_conntrack_info ctinfo; struct nf_conn *ct = nf_ct_get(skb, &ctinfo); + struct nf_conn_help *help = nfct_help(ct); if ((code >= 100 && code <= 199) || (code >= 200 && code <= 299)) return process_sdp(skb, dptr, datalen, cseq); - else { + else if (help->help.ct_sip_info.invite_cseq == cseq) flush_expectations(ct, true); - return NF_ACCEPT; - } + return NF_ACCEPT; } static int process_bye_request(struct sk_buff *skb, -- 2.39.5