--- /dev/null
+diff -urN linux-2.4.32/net/ipv4/netfilter/Config.in linux-2.4.32/net/ipv4/netfilter/Config.in
+--- linux-2.4.32/net/ipv4/netfilter/Config.in 2005-12-12 11:13:17.000000000 +0100
++++ linux-2.4.32/net/ipv4/netfilter/Config.in 2005-12-12 11:18:47.000000000 +0100
+@@ -16,6 +16,7 @@
+ dep_tristate ' GRE protocol support' CONFIG_IP_NF_CT_PROTO_GRE $CONFIG_IP_NF_CONNTRACK
+ dep_tristate ' PPTP protocol support' CONFIG_IP_NF_PPTP $CONFIG_IP_NF_CT_PROTO_GRE
+ dep_tristate ' SIP protocol support' CONFIG_IP_NF_SIP $CONFIG_IP_NF_CONNTRACK
++ dep_tristate ' H.323 (netmeeting) support' CONFIG_IP_NF_H323 $CONFIG_IP_NF_CONNTRACK
+ fi
+
+ if [ "$CONFIG_EXPERIMENTAL" = "y" ]; then
+@@ -112,6 +113,13 @@
+ define_tristate CONFIG_IP_NF_NAT_SIP $CONFIG_IP_NF_NAT
+ fi
+ fi
++ if [ "$CONFIG_IP_NF_H323" = "m" ]; then
++ define_tristate CONFIG_IP_NF_NAT_H323 m
++ else
++ if [ "$CONFIG_IP_NF_H323" = "y" ]; then
++ define_tristate CONFIG_IP_NF_NAT_H323 $CONFIG_IP_NF_NAT
++ fi
++ fi
+ if [ "$CONFIG_IP_NF_AMANDA" = "m" ]; then
+ define_tristate CONFIG_IP_NF_NAT_AMANDA m
+ else
+diff -urN linux-2.4.32/net/ipv4/netfilter/Makefile linux-2.4.32/net/ipv4/netfilter/Makefile
+--- linux-2.4.32/net/ipv4/netfilter/Makefile 2005-12-12 11:13:17.000000000 +0100
++++ linux-2.4.32/net/ipv4/netfilter/Makefile 2005-12-12 11:17:37.000000000 +0100
+@@ -57,6 +57,10 @@
+ ifdef CONFIG_IP_NF_NAT_SIP
+ export-objs += ip_conntrack_sip.o
+ endif
++obj-$(CONFIG_IP_NF_H323) += ip_conntrack_h323.o
++ifdef CONFIG_IP_NF_NAT_H323
++ export-objs += ip_conntrack_h323.o
++endif
+
+
+ # NAT helpers
+@@ -67,6 +71,7 @@
+ obj-$(CONFIG_IP_NF_NAT_PROTO_GRE) += ip_nat_proto_gre.o
+ obj-$(CONFIG_IP_NF_NAT_PPTP) += ip_nat_pptp.o
+ obj-$(CONFIG_IP_NF_NAT_SIP) += ip_nat_sip.o
++obj-$(CONFIG_IP_NF_NAT_H323) += ip_nat_h323.o
+
+ # generic IP tables
+ obj-$(CONFIG_IP_NF_IPTABLES) += ip_tables.o
+diff -urN linux-2.4.32/net/ipv4/netfilter/ip_conntrack_h323.c linux-2.4.32/net/ipv4/netfilter/ip_conntrack_h323.c
+--- linux-2.4.32/net/ipv4/netfilter/ip_conntrack_h323.c 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.4.32/net/ipv4/netfilter/ip_conntrack_h323.c 2005-12-12 11:14:54.000000000 +0100
+@@ -0,0 +1,302 @@
++/*
++ * H.323 'brute force' extension for H.323 connection tracking.
++ * Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
++ *
++ * Based on ip_masq_h323.c for 2.2 kernels from CoRiTel, Sofia project.
++ * (http://www.coritel.it/projects/sofia/nat/)
++ * Uses Sampsa Ranta's excellent idea on using expectfn to 'bind'
++ * the unregistered helpers to the conntrack entries.
++ */
++
++
++#include <linux/module.h>
++#include <linux/netfilter.h>
++#include <linux/ip.h>
++#include <net/checksum.h>
++#include <net/tcp.h>
++
++#include <linux/netfilter_ipv4/lockhelp.h>
++#include <linux/netfilter_ipv4/ip_conntrack.h>
++#include <linux/netfilter_ipv4/ip_conntrack_core.h>
++#include <linux/netfilter_ipv4/ip_conntrack_helper.h>
++#include <linux/netfilter_ipv4/ip_conntrack_tuple.h>
++#include <linux/netfilter_ipv4/ip_conntrack_h323.h>
++
++MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
++MODULE_DESCRIPTION("H.323 'brute force' connection tracking module");
++MODULE_LICENSE("GPL");
++
++DECLARE_LOCK(ip_h323_lock);
++struct module *ip_conntrack_h323 = THIS_MODULE;
++
++#define DEBUGP(format, args...)
++
++static int h245_help(const struct iphdr *iph, size_t len,
++ struct ip_conntrack *ct,
++ enum ip_conntrack_info ctinfo)
++{
++ struct tcphdr *tcph = (void *)iph + iph->ihl * 4;
++ unsigned char *data = (unsigned char *) tcph + tcph->doff * 4;
++ unsigned char *data_limit;
++ u_int32_t tcplen = len - iph->ihl * 4;
++ u_int32_t datalen = tcplen - tcph->doff * 4;
++ int dir = CTINFO2DIR(ctinfo);
++ struct ip_ct_h225_master *info = &ct->help.ct_h225_info;
++ struct ip_conntrack_expect expect, *exp = &expect;
++ struct ip_ct_h225_expect *exp_info = &exp->help.exp_h225_info;
++ u_int16_t data_port;
++ u_int32_t data_ip;
++ unsigned int i;
++
++ DEBUGP("ct_h245_help: help entered %u.%u.%u.%u:%u->%u.%u.%u.%u:%u\n",
++ NIPQUAD(iph->saddr), ntohs(tcph->source),
++ NIPQUAD(iph->daddr), ntohs(tcph->dest));
++
++ /* Can't track connections formed before we registered */
++ if (!info)
++ return NF_ACCEPT;
++
++ /* Until there's been traffic both ways, don't look in packets. */
++ if (ctinfo != IP_CT_ESTABLISHED
++ && ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
++ DEBUGP("ct_h245_help: Conntrackinfo = %u\n", ctinfo);
++ return NF_ACCEPT;
++ }
++
++ /* Not whole TCP header or too short packet? */
++ if (tcplen < sizeof(struct tcphdr) || tcplen < tcph->doff * 4 + 5) {
++ DEBUGP("ct_h245_help: tcplen = %u\n", (unsigned)tcplen);
++ return NF_ACCEPT;
++ }
++
++ /* Checksum invalid? Ignore. */
++ if (tcp_v4_check(tcph, tcplen, iph->saddr, iph->daddr,
++ csum_partial((char *)tcph, tcplen, 0))) {
++ DEBUGP("ct_h245_help: bad csum: %p %u %u.%u.%u.%u %u.%u.%u.%u\n",
++ tcph, tcplen, NIPQUAD(iph->saddr),
++ NIPQUAD(iph->daddr));
++ return NF_ACCEPT;
++ }
++
++ data_limit = (unsigned char *) data + datalen;
++ /* bytes: 0123 45
++ ipadrr port */
++ for (i = 0; data < (data_limit - 5); data++, i++) {
++ memcpy(&data_ip, data, sizeof(u_int32_t));
++ if (data_ip == iph->saddr) {
++ memcpy(&data_port, data + 4, sizeof(u_int16_t));
++ memset(&expect, 0, sizeof(expect));
++ /* update the H.225 info */
++ DEBUGP("ct_h245_help: new RTCP/RTP requested %u.%u.%u.%u:->%u.%u.%u.%u:%u\n",
++ NIPQUAD(ct->tuplehash[!dir].tuple.src.ip),
++ NIPQUAD(iph->saddr), ntohs(data_port));
++ LOCK_BH(&ip_h323_lock);
++ info->is_h225 = H225_PORT + 1;
++ exp_info->port = data_port;
++ exp_info->dir = dir;
++ exp_info->offset = i;
++
++ exp->seq = ntohl(tcph->seq) + i;
++
++ exp->tuple = ((struct ip_conntrack_tuple)
++ { { ct->tuplehash[!dir].tuple.src.ip,
++ { 0 } },
++ { data_ip,
++ { data_port },
++ IPPROTO_UDP }});
++ exp->mask = ((struct ip_conntrack_tuple)
++ { { 0xFFFFFFFF, { 0 } },
++ { 0xFFFFFFFF, { 0xFFFF }, 0xFFFF }});
++
++ exp->expectfn = NULL;
++
++ /* Ignore failure; should only happen with NAT */
++ ip_conntrack_expect_related(ct, exp);
++
++ UNLOCK_BH(&ip_h323_lock);
++ }
++ }
++
++ return NF_ACCEPT;
++
++}
++
++/* H.245 helper is not registered! */
++static struct ip_conntrack_helper h245 =
++ { { NULL, NULL },
++ "H.245", /* name */
++ IP_CT_HELPER_F_REUSE_EXPECT, /* flags */
++ NULL, /* module */
++ 8, /* max_ expected */
++ 240, /* timeout */
++ { { 0, { 0 } }, /* tuple */
++ { 0, { 0 }, IPPROTO_TCP } },
++ { { 0, { 0xFFFF } }, /* mask */
++ { 0, { 0 }, 0xFFFF } },
++ h245_help /* helper */
++ };
++
++static int h225_expect(struct ip_conntrack *ct)
++{
++ WRITE_LOCK(&ip_conntrack_lock);
++ ct->helper = &h245;
++ DEBUGP("h225_expect: helper for %p added\n", ct);
++ WRITE_UNLOCK(&ip_conntrack_lock);
++
++ return NF_ACCEPT; /* unused */
++}
++
++static int h225_help(const struct iphdr *iph, size_t len,
++ struct ip_conntrack *ct,
++ enum ip_conntrack_info ctinfo)
++{
++ struct tcphdr *tcph = (void *)iph + iph->ihl * 4;
++ unsigned char *data = (unsigned char *) tcph + tcph->doff * 4;
++ unsigned char *data_limit;
++ u_int32_t tcplen = len - iph->ihl * 4;
++ u_int32_t datalen = tcplen - tcph->doff * 4;
++ int dir = CTINFO2DIR(ctinfo);
++ struct ip_ct_h225_master *info = &ct->help.ct_h225_info;
++ struct ip_conntrack_expect expect, *exp = &expect;
++ struct ip_ct_h225_expect *exp_info = &exp->help.exp_h225_info;
++ u_int16_t data_port;
++ u_int32_t data_ip;
++ unsigned int i;
++
++ DEBUGP("ct_h225_help: help entered %u.%u.%u.%u:%u->%u.%u.%u.%u:%u\n",
++ NIPQUAD(iph->saddr), ntohs(tcph->source),
++ NIPQUAD(iph->daddr), ntohs(tcph->dest));
++
++ /* Can't track connections formed before we registered */
++ if (!info)
++ return NF_ACCEPT;
++
++ /* Until there's been traffic both ways, don't look in packets. */
++ if (ctinfo != IP_CT_ESTABLISHED
++ && ctinfo != IP_CT_ESTABLISHED + IP_CT_IS_REPLY) {
++ DEBUGP("ct_h225_help: Conntrackinfo = %u\n", ctinfo);
++ return NF_ACCEPT;
++ }
++
++ /* Not whole TCP header or too short packet? */
++ if (tcplen < sizeof(struct tcphdr) || tcplen < tcph->doff * 4 + 5) {
++ DEBUGP("ct_h225_help: tcplen = %u\n", (unsigned)tcplen);
++ return NF_ACCEPT;
++ }
++
++ /* Checksum invalid? Ignore. */
++ if (tcp_v4_check(tcph, tcplen, iph->saddr, iph->daddr,
++ csum_partial((char *)tcph, tcplen, 0))) {
++ DEBUGP("ct_h225_help: bad csum: %p %u %u.%u.%u.%u %u.%u.%u.%u\n",
++ tcph, tcplen, NIPQUAD(iph->saddr),
++ NIPQUAD(iph->daddr));
++ return NF_ACCEPT;
++ }
++
++ data_limit = (unsigned char *) data + datalen;
++ /* bytes: 0123 45
++ ipadrr port */
++ for (i = 0; data < (data_limit - 5); data++, i++) {
++ memcpy(&data_ip, data, sizeof(u_int32_t));
++ if (data_ip == iph->saddr) {
++ memcpy(&data_port, data + 4, sizeof(u_int16_t));
++ if (data_port == tcph->source) {
++ /* Signal address */
++ DEBUGP("ct_h225_help: sourceCallSignalAddress from %u.%u.%u.%u\n",
++ NIPQUAD(iph->saddr));
++ /* Update the H.225 info so that NAT can mangle the address/port
++ even when we have no expected connection! */
++#ifdef CONFIG_IP_NF_NAT_NEEDED
++ LOCK_BH(&ip_h323_lock);
++ info->dir = dir;
++ info->seq[IP_CT_DIR_ORIGINAL] = ntohl(tcph->seq) + i;
++ info->offset[IP_CT_DIR_ORIGINAL] = i;
++ UNLOCK_BH(&ip_h323_lock);
++#endif
++ } else {
++ memset(&expect, 0, sizeof(expect));
++
++ /* update the H.225 info */
++ LOCK_BH(&ip_h323_lock);
++ info->is_h225 = H225_PORT;
++ exp_info->port = data_port;
++ exp_info->dir = dir;
++ exp_info->offset = i;
++
++ exp->seq = ntohl(tcph->seq) + i;
++
++ exp->tuple = ((struct ip_conntrack_tuple)
++ { { ct->tuplehash[!dir].tuple.src.ip,
++ { 0 } },
++ { data_ip,
++ { data_port },
++ IPPROTO_TCP }});
++ exp->mask = ((struct ip_conntrack_tuple)
++ { { 0xFFFFFFFF, { 0 } },
++ { 0xFFFFFFFF, { 0xFFFF }, 0xFFFF }});
++
++ exp->expectfn = h225_expect;
++
++ /* Ignore failure */
++ ip_conntrack_expect_related(ct, exp);
++
++ DEBUGP("ct_h225_help: new H.245 requested %u.%u.%u.%u->%u.%u.%u.%u:%u\n",
++ NIPQUAD(ct->tuplehash[!dir].tuple.src.ip),
++ NIPQUAD(iph->saddr), ntohs(data_port));
++
++ UNLOCK_BH(&ip_h323_lock);
++ }
++#ifdef CONFIG_IP_NF_NAT_NEEDED
++ } else if (data_ip == iph->daddr) {
++ memcpy(&data_port, data + 4, sizeof(u_int16_t));
++ if (data_port == tcph->dest) {
++ /* Signal address */
++ DEBUGP("ct_h225_help: destCallSignalAddress %u.%u.%u.%u\n",
++ NIPQUAD(iph->daddr));
++ /* Update the H.225 info so that NAT can mangle the address/port
++ even when we have no expected connection! */
++ LOCK_BH(&ip_h323_lock);
++ info->dir = dir;
++ info->seq[IP_CT_DIR_REPLY] = ntohl(tcph->seq) + i;
++ info->offset[IP_CT_DIR_REPLY] = i;
++ UNLOCK_BH(&ip_h323_lock);
++ }
++#endif
++ }
++ }
++
++ return NF_ACCEPT;
++
++}
++
++static struct ip_conntrack_helper h225 =
++ { { NULL, NULL },
++ "H.225", /* name */
++ IP_CT_HELPER_F_REUSE_EXPECT, /* flags */
++ THIS_MODULE, /* module */
++ 2, /* max_expected */
++ 240, /* timeout */
++ { { 0, { __constant_htons(H225_PORT) } }, /* tuple */
++ { 0, { 0 }, IPPROTO_TCP } },
++ { { 0, { 0xFFFF } }, /* mask */
++ { 0, { 0 }, 0xFFFF } },
++ h225_help /* helper */
++ };
++
++static int __init init(void)
++{
++ return ip_conntrack_helper_register(&h225);
++}
++
++static void __exit fini(void)
++{
++ /* Unregister H.225 helper */
++ ip_conntrack_helper_unregister(&h225);
++}
++
++#ifdef CONFIG_IP_NF_NAT_NEEDED
++EXPORT_SYMBOL(ip_h323_lock);
++#endif
++
++module_init(init);
++module_exit(fini);
+diff -urN linux-2.4.32/net/ipv4/netfilter/ip_nat_h323.c /linux-2.4.32/net/ipv4/netfilter/ip_nat_h323.c
+--- linux-2.4.32/net/ipv4/netfilter/ip_nat_h323.c 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.4.32/net/ipv4/netfilter/ip_nat_h323.c 2005-12-12 11:14:54.000000000 +0100
+@@ -0,0 +1,403 @@
++/*
++ * H.323 'brute force' extension for NAT alteration.
++ * Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
++ *
++ * Based on ip_masq_h323.c for 2.2 kernels from CoRiTel, Sofia project.
++ * (http://www.coritel.it/projects/sofia/nat.html)
++ * Uses Sampsa Ranta's excellent idea on using expectfn to 'bind'
++ * the unregistered helpers to the conntrack entries.
++ */
++
++
++#include <linux/module.h>
++#include <linux/netfilter.h>
++#include <linux/ip.h>
++#include <net/checksum.h>
++#include <net/tcp.h>
++
++#include <linux/netfilter_ipv4/lockhelp.h>
++#include <linux/netfilter_ipv4/ip_nat.h>
++#include <linux/netfilter_ipv4/ip_nat_helper.h>
++#include <linux/netfilter_ipv4/ip_nat_rule.h>
++#include <linux/netfilter_ipv4/ip_conntrack_tuple.h>
++#include <linux/netfilter_ipv4/ip_conntrack_helper.h>
++#include <linux/netfilter_ipv4/ip_conntrack_h323.h>
++
++MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
++MODULE_DESCRIPTION("H.323 'brute force' connection tracking module");
++MODULE_LICENSE("GPL");
++
++DECLARE_LOCK_EXTERN(ip_h323_lock);
++struct module *ip_nat_h323 = THIS_MODULE;
++
++#define DEBUGP(format, args...)
++
++
++static unsigned int
++h225_nat_expected(struct sk_buff **pskb,
++ unsigned int hooknum,
++ struct ip_conntrack *ct,
++ struct ip_nat_info *info);
++
++static unsigned int h225_nat_help(struct ip_conntrack *ct,
++ struct ip_conntrack_expect *exp,
++ struct ip_nat_info *info,
++ enum ip_conntrack_info ctinfo,
++ unsigned int hooknum,
++ struct sk_buff **pskb);
++
++static struct ip_nat_helper h245 =
++ { { NULL, NULL },
++ "H.245", /* name */
++ 0, /* flags */
++ NULL, /* module */
++ { { 0, { 0 } }, /* tuple */
++ { 0, { 0 }, IPPROTO_TCP } },
++ { { 0, { 0xFFFF } }, /* mask */
++ { 0, { 0 }, 0xFFFF } },
++ h225_nat_help, /* helper */
++ h225_nat_expected /* expectfn */
++ };
++
++static unsigned int
++h225_nat_expected(struct sk_buff **pskb,
++ unsigned int hooknum,
++ struct ip_conntrack *ct,
++ struct ip_nat_info *info)
++{
++ struct ip_nat_multi_range mr;
++ u_int32_t newdstip, newsrcip, newip;
++ u_int16_t port;
++ struct ip_ct_h225_expect *exp_info;
++ struct ip_ct_h225_master *master_info;
++ struct ip_conntrack *master = master_ct(ct);
++ unsigned int is_h225, ret;
++
++ IP_NF_ASSERT(info);
++ IP_NF_ASSERT(master);
++
++ IP_NF_ASSERT(!(info->initialized & (1<<HOOK2MANIP(hooknum))));
++
++ DEBUGP("h225_nat_expected: We have a connection!\n");
++ master_info = &ct->master->expectant->help.ct_h225_info;
++ exp_info = &ct->master->help.exp_h225_info;
++
++ LOCK_BH(&ip_h323_lock);
++
++ DEBUGP("master: ");
++ DUMP_TUPLE(&master->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
++ DUMP_TUPLE(&master->tuplehash[IP_CT_DIR_REPLY].tuple);
++ DEBUGP("conntrack: ");
++ DUMP_TUPLE(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
++ if (exp_info->dir == IP_CT_DIR_ORIGINAL) {
++ /* Make connection go to the client. */
++ newdstip = master->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip;
++ newsrcip = master->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.ip;
++ DEBUGP("h225_nat_expected: %u.%u.%u.%u->%u.%u.%u.%u (to client)\n",
++ NIPQUAD(newsrcip), NIPQUAD(newdstip));
++ } else {
++ /* Make the connection go to the server */
++ newdstip = master->tuplehash[IP_CT_DIR_REPLY].tuple.src.ip;
++ newsrcip = master->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip;
++ DEBUGP("h225_nat_expected: %u.%u.%u.%u->%u.%u.%u.%u (to server)\n",
++ NIPQUAD(newsrcip), NIPQUAD(newdstip));
++ }
++ port = exp_info->port;
++ is_h225 = master_info->is_h225 == H225_PORT;
++ UNLOCK_BH(&ip_h323_lock);
++
++ if (HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC)
++ newip = newsrcip;
++ else
++ newip = newdstip;
++
++ DEBUGP("h225_nat_expected: IP to %u.%u.%u.%u\n", NIPQUAD(newip));
++
++ mr.rangesize = 1;
++ /* We don't want to manip the per-protocol, just the IPs... */
++ mr.range[0].flags = IP_NAT_RANGE_MAP_IPS;
++ mr.range[0].min_ip = mr.range[0].max_ip = newip;
++
++ /* ... unless we're doing a MANIP_DST, in which case, make
++ sure we map to the correct port */
++ if (HOOK2MANIP(hooknum) == IP_NAT_MANIP_DST) {
++ mr.range[0].flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
++ mr.range[0].min = mr.range[0].max
++ = ((union ip_conntrack_manip_proto)
++ { port });
++ }
++
++ ret = ip_nat_setup_info(ct, &mr, hooknum);
++
++ if (is_h225) {
++ DEBUGP("h225_nat_expected: H.225, setting NAT helper for %p\n", ct);
++ /* NAT expectfn called with ip_nat_lock write-locked */
++ info->helper = &h245;
++ }
++ return ret;
++}
++
++static int h323_signal_address_fixup(struct ip_conntrack *ct,
++ struct sk_buff **pskb,
++ enum ip_conntrack_info ctinfo)
++{
++ struct iphdr *iph = (*pskb)->nh.iph;
++ struct tcphdr *tcph = (void *)iph + iph->ihl*4;
++ unsigned char *data;
++ u_int32_t tcplen = (*pskb)->len - iph->ihl*4;
++ u_int32_t datalen = tcplen - tcph->doff*4;
++ struct ip_ct_h225_master *info = &ct->help.ct_h225_info;
++ u_int32_t newip;
++ u_int16_t port;
++ u_int8_t buffer[6];
++ int i;
++
++ MUST_BE_LOCKED(&ip_h323_lock);
++
++ DEBUGP("h323_signal_address_fixup: %s %s\n",
++ between(info->seq[IP_CT_DIR_ORIGINAL], ntohl(tcph->seq), ntohl(tcph->seq) + datalen)
++ ? "yes" : "no",
++ between(info->seq[IP_CT_DIR_REPLY], ntohl(tcph->seq), ntohl(tcph->seq) + datalen)
++ ? "yes" : "no");
++ if (!(between(info->seq[IP_CT_DIR_ORIGINAL], ntohl(tcph->seq), ntohl(tcph->seq) + datalen)
++ || between(info->seq[IP_CT_DIR_REPLY], ntohl(tcph->seq), ntohl(tcph->seq) + datalen)))
++ return 1;
++
++ DEBUGP("h323_signal_address_fixup: offsets %u + 6 and %u + 6 in %u\n",
++ info->offset[IP_CT_DIR_ORIGINAL],
++ info->offset[IP_CT_DIR_REPLY],
++ tcplen);
++ DUMP_TUPLE(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
++ DUMP_TUPLE(&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
++
++ for (i = 0; i < IP_CT_DIR_MAX; i++) {
++ DEBUGP("h323_signal_address_fixup: %s %s\n",
++ info->dir == IP_CT_DIR_ORIGINAL ? "original" : "reply",
++ i == IP_CT_DIR_ORIGINAL ? "caller" : "callee");
++ if (!between(info->seq[i], ntohl(tcph->seq),
++ ntohl(tcph->seq) + datalen))
++ continue;
++ if (!between(info->seq[i] + 6, ntohl(tcph->seq),
++ ntohl(tcph->seq) + datalen)) {
++ /* Partial retransmisison. It's a cracker being funky. */
++ if (net_ratelimit()) {
++ printk("H.323_NAT: partial packet %u/6 in %u/%u\n",
++ info->seq[i],
++ ntohl(tcph->seq),
++ ntohl(tcph->seq) + datalen);
++ }
++ return 0;
++ }
++
++ /* Change address inside packet to match way we're mapping
++ this connection. */
++ if (i == IP_CT_DIR_ORIGINAL) {
++ newip = ct->tuplehash[!info->dir].tuple.dst.ip;
++ port = ct->tuplehash[!info->dir].tuple.dst.u.tcp.port;
++ } else {
++ newip = ct->tuplehash[!info->dir].tuple.src.ip;
++ port = ct->tuplehash[!info->dir].tuple.src.u.tcp.port;
++ }
++
++ data = (char *) tcph + tcph->doff * 4 + info->offset[i];
++
++ DEBUGP("h323_signal_address_fixup: orig %s IP:port %u.%u.%u.%u:%u\n",
++ i == IP_CT_DIR_ORIGINAL ? "source" : "dest ",
++ data[0], data[1], data[2], data[3],
++ (data[4] << 8 | data[5]));
++
++ /* Modify the packet */
++ memcpy(buffer, &newip, 4);
++ memcpy(buffer + 4, &port, 2);
++ if (!ip_nat_mangle_tcp_packet(pskb, ct, ctinfo, info->offset[i],
++ 6, buffer, 6))
++ return 0;
++
++ DEBUGP("h323_signal_address_fixup: new %s IP:port %u.%u.%u.%u:%u\n",
++ i == IP_CT_DIR_ORIGINAL ? "source" : "dest ",
++ data[0], data[1], data[2], data[3],
++ (data[4] << 8 | data[5]));
++ }
++
++ return 1;
++}
++
++static int h323_data_fixup(struct ip_ct_h225_expect *info,
++ struct ip_conntrack *ct,
++ struct sk_buff **pskb,
++ enum ip_conntrack_info ctinfo,
++ struct ip_conntrack_expect *expect)
++{
++ u_int32_t newip;
++ u_int16_t port;
++ u_int8_t buffer[6];
++ struct ip_conntrack_tuple newtuple;
++ struct iphdr *iph = (*pskb)->nh.iph;
++ struct tcphdr *tcph = (void *)iph + iph->ihl*4;
++ unsigned char *data;
++ u_int32_t tcplen = (*pskb)->len - iph->ihl*4;
++ struct ip_ct_h225_master *master_info = &ct->help.ct_h225_info;
++ int is_h225;
++
++ MUST_BE_LOCKED(&ip_h323_lock);
++ DEBUGP("h323_data_fixup: offset %u + 6 in %u\n", info->offset, tcplen);
++ DUMP_TUPLE(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
++ DUMP_TUPLE(&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
++
++ if (!between(expect->seq + 6, ntohl(tcph->seq),
++ ntohl(tcph->seq) + tcplen - tcph->doff * 4)) {
++ /* Partial retransmisison. It's a cracker being funky. */
++ if (net_ratelimit()) {
++ printk("H.323_NAT: partial packet %u/6 in %u/%u\n",
++ expect->seq,
++ ntohl(tcph->seq),
++ ntohl(tcph->seq) + tcplen - tcph->doff * 4);
++ }
++ return 0;
++ }
++
++ /* Change address inside packet to match way we're mapping
++ this connection. */
++ if (info->dir == IP_CT_DIR_REPLY) {
++ /* Must be where client thinks server is */
++ newip = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.ip;
++ /* Expect something from client->server */
++ newtuple.src.ip = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip;
++ newtuple.dst.ip = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.ip;
++ } else {
++ /* Must be where server thinks client is */
++ newip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip;
++ /* Expect something from server->client */
++ newtuple.src.ip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.src.ip;
++ newtuple.dst.ip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip;
++ }
++
++ is_h225 = (master_info->is_h225 == H225_PORT);
++
++ if (is_h225) {
++ newtuple.dst.protonum = IPPROTO_TCP;
++ newtuple.src.u.tcp.port = expect->tuple.src.u.tcp.port;
++ } else {
++ newtuple.dst.protonum = IPPROTO_UDP;
++ newtuple.src.u.udp.port = expect->tuple.src.u.udp.port;
++ }
++
++ /* Try to get same port: if not, try to change it. */
++ for (port = ntohs(info->port); port != 0; port++) {
++ if (is_h225)
++ newtuple.dst.u.tcp.port = htons(port);
++ else
++ newtuple.dst.u.udp.port = htons(port);
++
++ if (ip_conntrack_change_expect(expect, &newtuple) == 0)
++ break;
++ }
++ if (port == 0) {
++ DEBUGP("h323_data_fixup: no free port found!\n");
++ return 0;
++ }
++
++ port = htons(port);
++
++ data = (char *) tcph + tcph->doff * 4 + info->offset;
++
++ DEBUGP("h323_data_fixup: orig IP:port %u.%u.%u.%u:%u\n",
++ data[0], data[1], data[2], data[3],
++ (data[4] << 8 | data[5]));
++
++ /* Modify the packet */
++ memcpy(buffer, &newip, 4);
++ memcpy(buffer + 4, &port, 2);
++ if (!ip_nat_mangle_tcp_packet(pskb, ct, ctinfo, info->offset,
++ 6, buffer, 6))
++ return 0;
++
++ DEBUGP("h323_data_fixup: new IP:port %u.%u.%u.%u:%u\n",
++ data[0], data[1], data[2], data[3],
++ (data[4] << 8 | data[5]));
++
++ return 1;
++}
++
++static unsigned int h225_nat_help(struct ip_conntrack *ct,
++ struct ip_conntrack_expect *exp,
++ struct ip_nat_info *info,
++ enum ip_conntrack_info ctinfo,
++ unsigned int hooknum,
++ struct sk_buff **pskb)
++{
++ int dir;
++ struct ip_ct_h225_expect *exp_info;
++
++ /* Only mangle things once: original direction in POST_ROUTING
++ and reply direction on PRE_ROUTING. */
++ dir = CTINFO2DIR(ctinfo);
++ DEBUGP("nat_h323: dir %s at hook %s\n",
++ dir == IP_CT_DIR_ORIGINAL ? "ORIG" : "REPLY",
++ hooknum == NF_IP_POST_ROUTING ? "POSTROUTING"
++ : hooknum == NF_IP_PRE_ROUTING ? "PREROUTING"
++ : hooknum == NF_IP_LOCAL_OUT ? "OUTPUT" : "???");
++ if (!((hooknum == NF_IP_POST_ROUTING && dir == IP_CT_DIR_ORIGINAL)
++ || (hooknum == NF_IP_PRE_ROUTING && dir == IP_CT_DIR_REPLY))) {
++ DEBUGP("nat_h323: Not touching dir %s at hook %s\n",
++ dir == IP_CT_DIR_ORIGINAL ? "ORIG" : "REPLY",
++ hooknum == NF_IP_POST_ROUTING ? "POSTROUTING"
++ : hooknum == NF_IP_PRE_ROUTING ? "PREROUTING"
++ : hooknum == NF_IP_LOCAL_OUT ? "OUTPUT" : "???");
++ return NF_ACCEPT;
++ }
++
++ if (!exp) {
++ LOCK_BH(&ip_h323_lock);
++ if (!h323_signal_address_fixup(ct, pskb, ctinfo)) {
++ UNLOCK_BH(&ip_h323_lock);
++ return NF_DROP;
++ }
++ UNLOCK_BH(&ip_h323_lock);
++ return NF_ACCEPT;
++ }
++
++ exp_info = &exp->help.exp_h225_info;
++
++ LOCK_BH(&ip_h323_lock);
++ if (!h323_data_fixup(exp_info, ct, pskb, ctinfo, exp)) {
++ UNLOCK_BH(&ip_h323_lock);
++ return NF_DROP;
++ }
++ UNLOCK_BH(&ip_h323_lock);
++
++ return NF_ACCEPT;
++}
++
++static struct ip_nat_helper h225 =
++ { { NULL, NULL },
++ "H.225", /* name */
++ IP_NAT_HELPER_F_ALWAYS, /* flags */
++ THIS_MODULE, /* module */
++ { { 0, { __constant_htons(H225_PORT) } }, /* tuple */
++ { 0, { 0 }, IPPROTO_TCP } },
++ { { 0, { 0xFFFF } }, /* mask */
++ { 0, { 0 }, 0xFFFF } },
++ h225_nat_help, /* helper */
++ h225_nat_expected /* expectfn */
++ };
++
++static int __init init(void)
++{
++ int ret;
++
++ ret = ip_nat_helper_register(&h225);
++
++ if (ret != 0)
++ printk("ip_nat_h323: cannot initialize the module!\n");
++
++ return ret;
++}
++
++static void __exit fini(void)
++{
++ ip_nat_helper_unregister(&h225);
++}
++
++module_init(init);
++module_exit(fini);
+diff -urN linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack.h linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack.h
+--- linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack.h 2005-12-12 11:13:17.000000000 +0100
++++ linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack.h 2005-12-12 11:16:13.000000000 +0100
+@@ -72,6 +72,7 @@
+ #include <linux/netfilter_ipv4/ip_conntrack_irc.h>
+ #include <linux/netfilter_ipv4/ip_conntrack_pptp.h>
+ #include <linux/netfilter_ipv4/ip_conntrack_sip.h>
++#include <linux/netfilter_ipv4/ip_conntrack_h323.h>
+
+ /* per expectation: application helper private data */
+ union ip_conntrack_expect_help {
+@@ -81,6 +82,7 @@
+ struct ip_ct_irc_expect exp_irc_info;
+ struct ip_ct_pptp_expect exp_pptp_info;
+ struct ip_ct_sip_expect exp_sip_info;
++ struct ip_ct_h225_expect exp_h225_info;
+
+ #ifdef CONFIG_IP_NF_NAT_NEEDED
+ union {
+@@ -96,6 +98,7 @@
+ struct ip_ct_irc_master ct_irc_info;
+ struct ip_ct_pptp_master ct_pptp_info;
+ struct ip_ct_sip_master ct_sip_info;
++ struct ip_ct_h225_master ct_h225_info;
+ };
+
+ #ifdef CONFIG_IP_NF_NAT_NEEDED
+diff -urN linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack_h323.h linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack_h323.h
+--- linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack_h323.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack_h323.h 2005-12-12 11:14:54.000000000 +0100
+@@ -0,0 +1,30 @@
++#ifndef _IP_CONNTRACK_H323_H
++#define _IP_CONNTRACK_H323_H
++/* H.323 connection tracking. */
++
++#ifdef __KERNEL__
++/* Protects H.323 related data */
++DECLARE_LOCK_EXTERN(ip_h323_lock);
++#endif
++
++/* Default H.225 port */
++#define H225_PORT 1720
++
++/* This structure is per expected connection */
++struct ip_ct_h225_expect {
++ u_int16_t port; /* Port of the H.225 helper/RTCP/RTP channel */
++ enum ip_conntrack_dir dir; /* Direction of the original connection */
++ unsigned int offset; /* offset of the address in the payload */
++};
++
++/* This structure exists only once per master */
++struct ip_ct_h225_master {
++ int is_h225; /* H.225 or H.245 connection */
++#ifdef CONFIG_IP_NF_NAT_NEEDED
++ enum ip_conntrack_dir dir; /* Direction of the original connection */
++ u_int32_t seq[IP_CT_DIR_MAX]; /* Exceptional packet mangling for signal addressess... */
++ unsigned int offset[IP_CT_DIR_MAX]; /* ...and the offset of the addresses in the payload */
++#endif
++};
++
++#endif /* _IP_CONNTRACK_H323_H */
projects / openwrt.git / commitdiff