*
* (C) 2005 by Christian Hentschel <chentschel@arnet.com.ar>
* based on RR's ip_conntrack_ftp.c and other modules.
+ * (C) 2007 United Security Providers
+ * (C) 2007, 2008 Patrick McHardy <kaber@trash.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
__read_mostly;
EXPORT_SYMBOL_GPL(nf_nat_sdp_addr_hook);
+unsigned int (*nf_nat_sdp_port_hook)(struct sk_buff *skb,
+ const char **dptr,
+ unsigned int *datalen,
+ unsigned int matchoff,
+ unsigned int matchlen,
+ u_int16_t port) __read_mostly;
+EXPORT_SYMBOL_GPL(nf_nat_sdp_port_hook);
+
unsigned int (*nf_nat_sdp_session_hook)(struct sk_buff *skb,
const char **dptr,
unsigned int dataoff,
const char *limit)
{
const char *end;
- int family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
int ret = 0;
- switch (family) {
+ memset(addr, 0, sizeof(*addr));
+ switch (nf_ct_l3num(ct)) {
case AF_INET:
ret = in4_pton(cp, limit - cp, (u8 *)&addr->ip, -1, &end);
break;
struct nf_conntrack_expect *exp, *rtp_exp, *rtcp_exp;
enum ip_conntrack_info ctinfo;
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
+ struct net *net = nf_ct_net(ct);
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
union nf_inet_addr *saddr;
struct nf_conntrack_tuple tuple;
- int family = ct->tuplehash[!dir].tuple.src.l3num;
- int skip_expect = 0, ret = NF_DROP;
+ int direct_rtp = 0, skip_expect = 0, ret = NF_DROP;
u_int16_t base_port;
__be16 rtp_port, rtcp_port;
+ typeof(nf_nat_sdp_port_hook) nf_nat_sdp_port;
typeof(nf_nat_sdp_media_hook) nf_nat_sdp_media;
saddr = NULL;
* to register it since we can see the same media description multiple
* times on different connections in case multiple endpoints receive
* the same call.
+ *
+ * RTP optimization: if we find a matching media channel expectation
+ * and both the expectation and this connection are SNATed, we assume
+ * both sides can reach each other directly and use the final
+ * destination address from the expectation. We still need to keep
+ * the NATed expectations for media that might arrive from the
+ * outside, and additionally need to expect the direct RTP stream
+ * in case it passes through us even without NAT.
*/
memset(&tuple, 0, sizeof(tuple));
if (saddr)
tuple.src.u3 = *saddr;
- tuple.src.l3num = family;
+ tuple.src.l3num = nf_ct_l3num(ct);
tuple.dst.protonum = IPPROTO_UDP;
tuple.dst.u3 = *daddr;
tuple.dst.u.udp.port = port;
rcu_read_lock();
- exp = __nf_ct_expect_find(&tuple);
- if (exp && exp->master != ct &&
- nfct_help(exp->master)->helper == nfct_help(ct)->helper &&
- exp->class == class)
- skip_expect = 1;
- rcu_read_unlock();
+ do {
+ exp = __nf_ct_expect_find(net, &tuple);
- if (skip_expect)
- return NF_ACCEPT;
+ if (!exp || exp->master == ct ||
+ nfct_help(exp->master)->helper != nfct_help(ct)->helper ||
+ exp->class != class)
+ break;
+#ifdef CONFIG_NF_NAT_NEEDED
+ if (exp->tuple.src.l3num == AF_INET && !direct_rtp &&
+ (exp->saved_ip != exp->tuple.dst.u3.ip ||
+ exp->saved_proto.udp.port != exp->tuple.dst.u.udp.port) &&
+ ct->status & IPS_NAT_MASK) {
+ daddr->ip = exp->saved_ip;
+ tuple.dst.u3.ip = exp->saved_ip;
+ tuple.dst.u.udp.port = exp->saved_proto.udp.port;
+ direct_rtp = 1;
+ } else
+#endif
+ skip_expect = 1;
+ } while (!skip_expect);
+ rcu_read_unlock();
base_port = ntohs(tuple.dst.u.udp.port) & ~1;
rtp_port = htons(base_port);
rtcp_port = htons(base_port + 1);
+ if (direct_rtp) {
+ nf_nat_sdp_port = rcu_dereference(nf_nat_sdp_port_hook);
+ if (nf_nat_sdp_port &&
+ !nf_nat_sdp_port(skb, dptr, datalen,
+ mediaoff, medialen, ntohs(rtp_port)))
+ goto err1;
+ }
+
+ if (skip_expect)
+ return NF_ACCEPT;
+
rtp_exp = nf_ct_expect_alloc(ct);
if (rtp_exp == NULL)
goto err1;
- nf_ct_expect_init(rtp_exp, class, family, saddr, daddr,
+ nf_ct_expect_init(rtp_exp, class, nf_ct_l3num(ct), saddr, daddr,
IPPROTO_UDP, NULL, &rtp_port);
rtcp_exp = nf_ct_expect_alloc(ct);
if (rtcp_exp == NULL)
goto err2;
- nf_ct_expect_init(rtcp_exp, class, family, saddr, daddr,
+ nf_ct_expect_init(rtcp_exp, class, nf_ct_l3num(ct), saddr, daddr,
IPPROTO_UDP, NULL, &rtcp_port);
nf_nat_sdp_media = rcu_dereference(nf_nat_sdp_media_hook);
- if (nf_nat_sdp_media && ct->status & IPS_NAT_MASK)
+ if (nf_nat_sdp_media && ct->status & IPS_NAT_MASK && !direct_rtp)
ret = nf_nat_sdp_media(skb, dptr, datalen, rtp_exp, rtcp_exp,
mediaoff, medialen, daddr);
else {
{
enum ip_conntrack_info ctinfo;
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
- int family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
+ struct nf_conn_help *help = nfct_help(ct);
unsigned int matchoff, matchlen;
unsigned int mediaoff, medialen;
unsigned int sdpoff;
typeof(nf_nat_sdp_session_hook) nf_nat_sdp_session;
nf_nat_sdp_addr = rcu_dereference(nf_nat_sdp_addr_hook);
- c_hdr = family == AF_INET ? SDP_HDR_CONNECTION_IP4 :
- SDP_HDR_CONNECTION_IP6;
+ c_hdr = nf_ct_l3num(ct) == AF_INET ? SDP_HDR_CONNECTION_IP4 :
+ SDP_HDR_CONNECTION_IP6;
/* Find beginning of session description */
if (ct_sip_get_sdp_header(ct, *dptr, 0, *datalen,
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,
{
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,
{
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,
{
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,
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
struct nf_conn_help *help = nfct_help(ct);
enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
- int family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
unsigned int matchoff, matchlen;
struct nf_conntrack_expect *exp;
union nf_inet_addr *saddr, daddr;
if (sip_direct_signalling)
saddr = &ct->tuplehash[!dir].tuple.src.u3;
- nf_ct_expect_init(exp, SIP_EXPECT_SIGNALLING, family, saddr, &daddr,
- IPPROTO_UDP, NULL, &port);
+ nf_ct_expect_init(exp, SIP_EXPECT_SIGNALLING, nf_ct_l3num(ct),
+ saddr, &daddr, IPPROTO_UDP, NULL, &port);
exp->timeout.expires = sip_timeout * HZ;
exp->helper = nfct_help(ct)->helper;
exp->flags = NF_CT_EXPECT_PERMANENT | NF_CT_EXPECT_INACTIVE;
static int process_sip_response(struct sk_buff *skb,
const char **dptr, unsigned int *datalen)
{
- static const struct sip_handler *handler;
enum ip_conntrack_info ctinfo;
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
unsigned int matchoff, matchlen;
dataoff = matchoff + matchlen + 1;
for (i = 0; i < ARRAY_SIZE(sip_handlers); i++) {
+ const struct sip_handler *handler;
+
handler = &sip_handlers[i];
if (handler->response == NULL)
continue;
static int process_sip_request(struct sk_buff *skb,
const char **dptr, unsigned int *datalen)
{
- static const struct sip_handler *handler;
enum ip_conntrack_info ctinfo;
struct nf_conn *ct = nf_ct_get(skb, &ctinfo);
unsigned int matchoff, matchlen;
unsigned int cseq, i;
for (i = 0; i < ARRAY_SIZE(sip_handlers); i++) {
+ const struct sip_handler *handler;
+
handler = &sip_handlers[i];
if (handler->request == NULL)
continue;