Commit f587de0e authored by Patrick McHardy's avatar Patrick McHardy Committed by David S. Miller

[NETFILTER]: nf_conntrack/nf_nat: add H.323 helper port

Add IPv4 and IPv6 capable nf_conntrack port of the H.323 conntrack/NAT helper.
Signed-off-by: default avatarPatrick McHardy <kaber@trash.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 16958900
#ifndef _NF_CONNTRACK_H323_H
#define _NF_CONNTRACK_H323_H
#ifdef __KERNEL__
#include <linux/netfilter/nf_conntrack_h323_asn1.h>
#define RAS_PORT 1719
#define Q931_PORT 1720
#define H323_RTP_CHANNEL_MAX 4 /* Audio, video, FAX and other */
/* This structure exists only once per master */
struct nf_ct_h323_master {
/* Original and NATed Q.931 or H.245 signal ports */
__be16 sig_port[IP_CT_DIR_MAX];
/* Original and NATed RTP ports */
__be16 rtp_port[H323_RTP_CHANNEL_MAX][IP_CT_DIR_MAX];
union {
/* RAS connection timeout */
u_int32_t timeout;
/* Next TPKT length (for separate TPKT header and data) */
u_int16_t tpkt_len[IP_CT_DIR_MAX];
};
};
struct nf_conn;
extern int get_h225_addr(struct nf_conn *ct, unsigned char *data,
TransportAddress *taddr,
union nf_conntrack_address *addr, __be16 *port);
extern void nf_conntrack_h245_expect(struct nf_conn *new,
struct nf_conntrack_expect *this);
extern void nf_conntrack_q931_expect(struct nf_conn *new,
struct nf_conntrack_expect *this);
extern int (*set_h245_addr_hook) (struct sk_buff **pskb,
unsigned char **data, int dataoff,
H245_TransportAddress *taddr,
union nf_conntrack_address *addr,
__be16 port);
extern int (*set_h225_addr_hook) (struct sk_buff **pskb,
unsigned char **data, int dataoff,
TransportAddress *taddr,
union nf_conntrack_address *addr,
__be16 port);
extern int (*set_sig_addr_hook) (struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data,
TransportAddress *taddr, int count);
extern int (*set_ras_addr_hook) (struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data,
TransportAddress *taddr, int count);
extern int (*nat_rtp_rtcp_hook) (struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
H245_TransportAddress *taddr,
__be16 port, __be16 rtp_port,
struct nf_conntrack_expect *rtp_exp,
struct nf_conntrack_expect *rtcp_exp);
extern int (*nat_t120_hook) (struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
H245_TransportAddress *taddr, __be16 port,
struct nf_conntrack_expect *exp);
extern int (*nat_h245_hook) (struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
TransportAddress *taddr, __be16 port,
struct nf_conntrack_expect *exp);
extern int (*nat_callforwarding_hook) (struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
TransportAddress *taddr,
__be16 port,
struct nf_conntrack_expect *exp);
extern int (*nat_q931_hook) (struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, TransportAddress *taddr,
int idx, __be16 port,
struct nf_conntrack_expect *exp);
#endif
#endif
/****************************************************************************
* ip_conntrack_helper_h323_asn1.h - BER and PER decoding library for H.323
* conntrack/NAT module.
* ip_conntrack_h323_asn1.h - BER and PER decoding library for H.323
* conntrack/NAT module.
*
* Copyright (c) 2006 by Jing Min Zhao <zhaojingmin@users.sourceforge.net>
*
......@@ -34,13 +34,13 @@
*
****************************************************************************/
#ifndef _IP_CONNTRACK_HELPER_H323_ASN1_H_
#define _IP_CONNTRACK_HELPER_H323_ASN1_H_
#ifndef _NF_CONNTRACK_HELPER_H323_ASN1_H_
#define _NF_CONNTRACK_HELPER_H323_ASN1_H_
/*****************************************************************************
* H.323 Types
****************************************************************************/
#include "ip_conntrack_helper_h323_types.h"
#include "nf_conntrack_h323_types.h"
typedef struct {
enum {
......
......@@ -10,6 +10,11 @@ typedef struct TransportAddress_ipAddress { /* SEQUENCE */
unsigned ip;
} TransportAddress_ipAddress;
typedef struct TransportAddress_ip6Address { /* SEQUENCE */
int options; /* No use */
unsigned ip6;
} TransportAddress_ip6Address;
typedef struct TransportAddress { /* CHOICE */
enum {
eTransportAddress_ipAddress,
......@@ -22,6 +27,7 @@ typedef struct TransportAddress { /* CHOICE */
} choice;
union {
TransportAddress_ipAddress ipAddress;
TransportAddress_ip6Address ip6Address;
};
} TransportAddress;
......@@ -93,6 +99,11 @@ typedef struct UnicastAddress_iPAddress { /* SEQUENCE */
unsigned network;
} UnicastAddress_iPAddress;
typedef struct UnicastAddress_iP6Address { /* SEQUENCE */
int options; /* No use */
unsigned network;
} UnicastAddress_iP6Address;
typedef struct UnicastAddress { /* CHOICE */
enum {
eUnicastAddress_iPAddress,
......@@ -105,6 +116,7 @@ typedef struct UnicastAddress { /* CHOICE */
} choice;
union {
UnicastAddress_iPAddress iPAddress;
UnicastAddress_iP6Address iP6Address;
};
} UnicastAddress;
......
header-y += ip_conntrack_helper.h
header-y += ip_conntrack_helper_h323_asn1.h
header-y += ip_conntrack_helper_h323_types.h
header-y += ip_conntrack_protocol.h
header-y += ip_conntrack_sctp.h
header-y += ip_conntrack_tcp.h
......
......@@ -3,7 +3,7 @@
#ifdef __KERNEL__
#include <linux/netfilter_ipv4/ip_conntrack_helper_h323_asn1.h>
#include <linux/netfilter/nf_conntrack_h323_asn1.h>
#define RAS_PORT 1719
#define Q931_PORT 1720
......
......@@ -41,11 +41,13 @@ union nf_conntrack_expect_proto {
/* Add protocol helper include file here */
#include <linux/netfilter/nf_conntrack_ftp.h>
#include <linux/netfilter/nf_conntrack_h323.h>
/* per conntrack: application helper private data */
union nf_conntrack_help {
/* insert conntrack helper private data (master) here */
struct nf_ct_ftp_master ct_ftp_info;
struct nf_ct_h323_master ct_h323_info;
};
#include <linux/types.h>
......
......@@ -41,6 +41,7 @@ struct nf_conntrack_expect
unsigned int flags;
#ifdef CONFIG_NF_NAT_NEEDED
__be32 saved_ip;
/* This is the original per-proto part, used to map the
* expected connection the way the recipient expects. */
union nf_conntrack_man_proto saved_proto;
......
......@@ -529,6 +529,11 @@ config IP_NF_NAT_H323
default IP_NF_NAT if IP_NF_H323=y
default m if IP_NF_H323=m
config NF_NAT_H323
tristate
depends on IP_NF_IPTABLES && NF_CONNTRACK && NF_NAT
default NF_NAT && NF_CONNTRACK_H323
config IP_NF_NAT_SIP
tristate
depends on IP_NF_IPTABLES!=n && IP_NF_CONNTRACK!=n && IP_NF_NAT!=n
......
......@@ -15,7 +15,7 @@ endif
ip_conntrack_pptp-objs := ip_conntrack_helper_pptp.o ip_conntrack_proto_gre.o
ip_nat_pptp-objs := ip_nat_helper_pptp.o ip_nat_proto_gre.o
ip_conntrack_h323-objs := ip_conntrack_helper_h323.o ip_conntrack_helper_h323_asn1.o
ip_conntrack_h323-objs := ip_conntrack_helper_h323.o ../../netfilter/nf_conntrack_h323_asn1.o
ip_nat_h323-objs := ip_nat_helper_h323.o
# connection tracking
......@@ -52,6 +52,7 @@ obj-$(CONFIG_IP_NF_NAT_SIP) += ip_nat_sip.o
# NAT helpers (nf_conntrack)
obj-$(CONFIG_NF_NAT_AMANDA) += nf_nat_amanda.o
obj-$(CONFIG_NF_NAT_FTP) += nf_nat_ftp.o
obj-$(CONFIG_NF_NAT_H323) += nf_nat_h323.o
# generic IP tables
obj-$(CONFIG_IP_NF_IPTABLES) += ip_tables.o
......
/*
* H.323 extension for NAT alteration.
*
* Copyright (c) 2006 Jing Min Zhao <zhaojingmin@users.sourceforge.net>
*
* This source code is licensed under General Public License version 2.
*
* Based on the 'brute force' H.323 NAT module by
* Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/tcp.h>
#include <net/tcp.h>
#include <net/netfilter/nf_nat.h>
#include <net/netfilter/nf_nat_helper.h>
#include <net/netfilter/nf_nat_rule.h>
#include <net/netfilter/nf_conntrack_helper.h>
#include <net/netfilter/nf_conntrack_expect.h>
#include <linux/netfilter/nf_conntrack_h323.h>
#if 0
#define DEBUGP printk
#else
#define DEBUGP(format, args...)
#endif
/****************************************************************************/
static int set_addr(struct sk_buff **pskb,
unsigned char **data, int dataoff,
unsigned int addroff, __be32 ip, __be16 port)
{
enum ip_conntrack_info ctinfo;
struct nf_conn *ct = ip_conntrack_get(*pskb, &ctinfo);
struct {
__be32 ip;
__be16 port;
} __attribute__ ((__packed__)) buf;
struct tcphdr _tcph, *th;
buf.ip = ip;
buf.port = port;
addroff += dataoff;
if ((*pskb)->nh.iph->protocol == IPPROTO_TCP) {
if (!nf_nat_mangle_tcp_packet(pskb, ct, ctinfo,
addroff, sizeof(buf),
(char *) &buf, sizeof(buf))) {
if (net_ratelimit())
printk("nf_nat_h323: nf_nat_mangle_tcp_packet"
" error\n");
return -1;
}
/* Relocate data pointer */
th = skb_header_pointer(*pskb, (*pskb)->nh.iph->ihl * 4,
sizeof(_tcph), &_tcph);
if (th == NULL)
return -1;
*data = (*pskb)->data + (*pskb)->nh.iph->ihl * 4 +
th->doff * 4 + dataoff;
} else {
if (!nf_nat_mangle_udp_packet(pskb, ct, ctinfo,
addroff, sizeof(buf),
(char *) &buf, sizeof(buf))) {
if (net_ratelimit())
printk("nf_nat_h323: nf_nat_mangle_udp_packet"
" error\n");
return -1;
}
/* nf_nat_mangle_udp_packet uses skb_make_writable() to copy
* or pull everything in a linear buffer, so we can safely
* use the skb pointers now */
*data = (*pskb)->data + (*pskb)->nh.iph->ihl * 4 +
sizeof(struct udphdr);
}
return 0;
}
/****************************************************************************/
static int set_h225_addr(struct sk_buff **pskb,
unsigned char **data, int dataoff,
TransportAddress *taddr,
union nf_conntrack_address *addr, __be16 port)
{
return set_addr(pskb, data, dataoff, taddr->ipAddress.ip,
addr->ip, port);
}
/****************************************************************************/
static int set_h245_addr(struct sk_buff **pskb,
unsigned char **data, int dataoff,
H245_TransportAddress *taddr,
union nf_conntrack_address *addr, __be16 port)
{
return set_addr(pskb, data, dataoff,
taddr->unicastAddress.iPAddress.network,
addr->ip, port);
}
/****************************************************************************/
static int set_sig_addr(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data,
TransportAddress *taddr, int count)
{
struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
int dir = CTINFO2DIR(ctinfo);
int i;
__be16 port;
union nf_conntrack_address addr;
for (i = 0; i < count; i++) {
if (get_h225_addr(ct, *data, &taddr[i], &addr, &port)) {
if (addr.ip == ct->tuplehash[dir].tuple.src.u3.ip &&
port == info->sig_port[dir]) {
/* GW->GK */
/* Fix for Gnomemeeting */
if (i > 0 &&
get_h225_addr(ct, *data, &taddr[0],
&addr, &port) &&
(ntohl(addr.ip) & 0xff000000) == 0x7f000000)
i = 0;
DEBUGP
("nf_nat_ras: set signal address "
"%u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n",
NIPQUAD(ip), port,
NIPQUAD(ct->tuplehash[!dir].tuple.dst.
ip), info->sig_port[!dir]);
return set_h225_addr(pskb, data, 0, &taddr[i],
&ct->tuplehash[!dir].
tuple.dst.u3,
info->sig_port[!dir]);
} else if (addr.ip == ct->tuplehash[dir].tuple.dst.u3.ip &&
port == info->sig_port[dir]) {
/* GK->GW */
DEBUGP
("nf_nat_ras: set signal address "
"%u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n",
NIPQUAD(ip), port,
NIPQUAD(ct->tuplehash[!dir].tuple.src.
ip), info->sig_port[!dir]);
return set_h225_addr(pskb, data, 0, &taddr[i],
&ct->tuplehash[!dir].
tuple.src.u3,
info->sig_port[!dir]);
}
}
}
return 0;
}
/****************************************************************************/
static int set_ras_addr(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data,
TransportAddress *taddr, int count)
{
int dir = CTINFO2DIR(ctinfo);
int i;
__be16 port;
union nf_conntrack_address addr;
for (i = 0; i < count; i++) {
if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
addr.ip == ct->tuplehash[dir].tuple.src.u3.ip &&
port == ct->tuplehash[dir].tuple.src.u.udp.port) {
DEBUGP("nf_nat_ras: set rasAddress "
"%u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n",
NIPQUAD(ip), ntohs(port),
NIPQUAD(ct->tuplehash[!dir].tuple.dst.u3.ip),
ntohs(ct->tuplehash[!dir].tuple.dst.u.udp.
port));
return set_h225_addr(pskb, data, 0, &taddr[i],
&ct->tuplehash[!dir].tuple.dst.u3,
ct->tuplehash[!dir].tuple.
dst.u.udp.port);
}
}
return 0;
}
/****************************************************************************/
static int nat_rtp_rtcp(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
H245_TransportAddress *taddr,
__be16 port, __be16 rtp_port,
struct nf_conntrack_expect *rtp_exp,
struct nf_conntrack_expect *rtcp_exp)
{
struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
int dir = CTINFO2DIR(ctinfo);
int i;
u_int16_t nated_port;
/* Set expectations for NAT */
rtp_exp->saved_proto.udp.port = rtp_exp->tuple.dst.u.udp.port;
rtp_exp->expectfn = nf_nat_follow_master;
rtp_exp->dir = !dir;
rtcp_exp->saved_proto.udp.port = rtcp_exp->tuple.dst.u.udp.port;
rtcp_exp->expectfn = nf_nat_follow_master;
rtcp_exp->dir = !dir;
/* Lookup existing expects */
for (i = 0; i < H323_RTP_CHANNEL_MAX; i++) {
if (info->rtp_port[i][dir] == rtp_port) {
/* Expected */
/* Use allocated ports first. This will refresh
* the expects */
rtp_exp->tuple.dst.u.udp.port = info->rtp_port[i][dir];
rtcp_exp->tuple.dst.u.udp.port =
htons(ntohs(info->rtp_port[i][dir]) + 1);
break;
} else if (info->rtp_port[i][dir] == 0) {
/* Not expected */
break;
}
}
/* Run out of expectations */
if (i >= H323_RTP_CHANNEL_MAX) {
if (net_ratelimit())
printk("nf_nat_h323: out of expectations\n");
return 0;
}
/* Try to get a pair of ports. */
for (nated_port = ntohs(rtp_exp->tuple.dst.u.udp.port);
nated_port != 0; nated_port += 2) {
rtp_exp->tuple.dst.u.udp.port = htons(nated_port);
if (nf_conntrack_expect_related(rtp_exp) == 0) {
rtcp_exp->tuple.dst.u.udp.port =
htons(nated_port + 1);
if (nf_conntrack_expect_related(rtcp_exp) == 0)
break;
nf_conntrack_unexpect_related(rtp_exp);
}
}
if (nated_port == 0) { /* No port available */
if (net_ratelimit())
printk("nf_nat_h323: out of RTP ports\n");
return 0;
}
/* Modify signal */
if (set_h245_addr(pskb, data, dataoff, taddr,
&ct->tuplehash[!dir].tuple.dst.u3,
htons((port & htons(1)) ? nated_port + 1 :
nated_port)) == 0) {
/* Save ports */
info->rtp_port[i][dir] = rtp_port;
info->rtp_port[i][!dir] = htons(nated_port);
} else {
nf_conntrack_unexpect_related(rtp_exp);
nf_conntrack_unexpect_related(rtcp_exp);
return -1;
}
/* Success */
DEBUGP("nf_nat_h323: expect RTP %u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n",
NIPQUAD(rtp_exp->tuple.src.ip),
ntohs(rtp_exp->tuple.src.u.udp.port),
NIPQUAD(rtp_exp->tuple.dst.ip),
ntohs(rtp_exp->tuple.dst.u.udp.port));
DEBUGP("nf_nat_h323: expect RTCP %u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n",
NIPQUAD(rtcp_exp->tuple.src.ip),
ntohs(rtcp_exp->tuple.src.u.udp.port),
NIPQUAD(rtcp_exp->tuple.dst.ip),
ntohs(rtcp_exp->tuple.dst.u.udp.port));
return 0;
}
/****************************************************************************/
static int nat_t120(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
H245_TransportAddress *taddr, __be16 port,
struct nf_conntrack_expect *exp)
{
int dir = CTINFO2DIR(ctinfo);
u_int16_t nated_port = ntohs(port);
/* Set expectations for NAT */
exp->saved_proto.tcp.port = exp->tuple.dst.u.tcp.port;
exp->expectfn = nf_nat_follow_master;
exp->dir = !dir;
/* Try to get same port: if not, try to change it. */
for (; nated_port != 0; nated_port++) {
exp->tuple.dst.u.tcp.port = htons(nated_port);
if (nf_conntrack_expect_related(exp) == 0)
break;
}
if (nated_port == 0) { /* No port available */
if (net_ratelimit())
printk("nf_nat_h323: out of TCP ports\n");
return 0;
}
/* Modify signal */
if (set_h245_addr(pskb, data, dataoff, taddr,
&ct->tuplehash[!dir].tuple.dst.u3,
htons(nated_port)) < 0) {
nf_conntrack_unexpect_related(exp);
return -1;
}
DEBUGP("nf_nat_h323: expect T.120 %u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n",
NIPQUAD(exp->tuple.src.ip), ntohs(exp->tuple.src.u.tcp.port),
NIPQUAD(exp->tuple.dst.ip), ntohs(exp->tuple.dst.u.tcp.port));
return 0;
}
/****************************************************************************/
static int nat_h245(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
TransportAddress *taddr, __be16 port,
struct nf_conntrack_expect *exp)
{
struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
int dir = CTINFO2DIR(ctinfo);
u_int16_t nated_port = ntohs(port);
/* Set expectations for NAT */
exp->saved_proto.tcp.port = exp->tuple.dst.u.tcp.port;
exp->expectfn = nf_nat_follow_master;
exp->dir = !dir;
/* Check existing expects */
if (info->sig_port[dir] == port)
nated_port = ntohs(info->sig_port[!dir]);
/* Try to get same port: if not, try to change it. */
for (; nated_port != 0; nated_port++) {
exp->tuple.dst.u.tcp.port = htons(nated_port);
if (nf_conntrack_expect_related(exp) == 0)
break;
}
if (nated_port == 0) { /* No port available */
if (net_ratelimit())
printk("nf_nat_q931: out of TCP ports\n");
return 0;
}
/* Modify signal */
if (set_h225_addr(pskb, data, dataoff, taddr,
&ct->tuplehash[!dir].tuple.dst.u3,
htons(nated_port)) == 0) {
/* Save ports */
info->sig_port[dir] = port;
info->sig_port[!dir] = htons(nated_port);
} else {
nf_conntrack_unexpect_related(exp);
return -1;
}
DEBUGP("nf_nat_q931: expect H.245 %u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n",
NIPQUAD(exp->tuple.src.ip), ntohs(exp->tuple.src.u.tcp.port),
NIPQUAD(exp->tuple.dst.ip), ntohs(exp->tuple.dst.u.tcp.port));
return 0;
}
/****************************************************************************
* This conntrack expect function replaces nf_conntrack_q931_expect()
* which was set by nf_conntrack_h323.c.
****************************************************************************/
static void ip_nat_q931_expect(struct nf_conn *new,
struct nf_conntrack_expect *this)
{
struct ip_nat_range range;
if (this->tuple.src.u3.ip != 0) { /* Only accept calls from GK */
nf_nat_follow_master(new, this);
return;
}
/* This must be a fresh one. */
BUG_ON(new->status & IPS_NAT_DONE_MASK);
/* Change src to where master sends to */
range.flags = IP_NAT_RANGE_MAP_IPS;
range.min_ip = range.max_ip = new->tuplehash[!this->dir].tuple.src.u3.ip;
/* hook doesn't matter, but it has to do source manip */
nf_nat_setup_info(new, &range, NF_IP_POST_ROUTING);
/* For DST manip, map port here to where it's expected. */
range.flags = (IP_NAT_RANGE_MAP_IPS | IP_NAT_RANGE_PROTO_SPECIFIED);
range.min = range.max = this->saved_proto;
range.min_ip = range.max_ip =
new->master->tuplehash[!this->dir].tuple.src.u3.ip;
/* hook doesn't matter, but it has to do destination manip */
nf_nat_setup_info(new, &range, NF_IP_PRE_ROUTING);
}
/****************************************************************************/
static int nat_q931(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, TransportAddress *taddr, int idx,
__be16 port, struct nf_conntrack_expect *exp)
{
struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
int dir = CTINFO2DIR(ctinfo);
u_int16_t nated_port = ntohs(port);
union nf_conntrack_address addr;
/* Set expectations for NAT */
exp->saved_proto.tcp.port = exp->tuple.dst.u.tcp.port;
exp->expectfn = ip_nat_q931_expect;
exp->dir = !dir;
/* Check existing expects */
if (info->sig_port[dir] == port)
nated_port = ntohs(info->sig_port[!dir]);
/* Try to get same port: if not, try to change it. */
for (; nated_port != 0; nated_port++) {
exp->tuple.dst.u.tcp.port = htons(nated_port);
if (nf_conntrack_expect_related(exp) == 0)
break;
}
if (nated_port == 0) { /* No port available */
if (net_ratelimit())
printk("nf_nat_ras: out of TCP ports\n");
return 0;
}
/* Modify signal */
if (set_h225_addr(pskb, data, 0, &taddr[idx],
&ct->tuplehash[!dir].tuple.dst.u3,
htons(nated_port)) == 0) {
/* Save ports */
info->sig_port[dir] = port;
info->sig_port[!dir] = htons(nated_port);
/* Fix for Gnomemeeting */
if (idx > 0 &&
get_h225_addr(ct, *data, &taddr[0], &addr, &port) &&
(ntohl(addr.ip) & 0xff000000) == 0x7f000000) {
set_h225_addr_hook(pskb, data, 0, &taddr[0],
&ct->tuplehash[!dir].tuple.dst.u3,
info->sig_port[!dir]);
}
} else {
nf_conntrack_unexpect_related(exp);
return -1;
}
/* Success */
DEBUGP("nf_nat_ras: expect Q.931 %u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n",
NIPQUAD(exp->tuple.src.ip), ntohs(exp->tuple.src.u.tcp.port),
NIPQUAD(exp->tuple.dst.ip), ntohs(exp->tuple.dst.u.tcp.port));
return 0;
}
/****************************************************************************/
static void ip_nat_callforwarding_expect(struct nf_conn *new,
struct nf_conntrack_expect *this)
{
struct nf_nat_range range;
/* This must be a fresh one. */
BUG_ON(new->status & IPS_NAT_DONE_MASK);
/* Change src to where master sends to */
range.flags = IP_NAT_RANGE_MAP_IPS;
range.min_ip = range.max_ip = new->tuplehash[!this->dir].tuple.src.u3.ip;
/* hook doesn't matter, but it has to do source manip */
nf_nat_setup_info(new, &range, NF_IP_POST_ROUTING);
/* For DST manip, map port here to where it's expected. */
range.flags = (IP_NAT_RANGE_MAP_IPS | IP_NAT_RANGE_PROTO_SPECIFIED);
range.min = range.max = this->saved_proto;
range.min_ip = range.max_ip = this->saved_ip;
/* hook doesn't matter, but it has to do destination manip */
nf_nat_setup_info(new, &range, NF_IP_PRE_ROUTING);
}
/****************************************************************************/
static int nat_callforwarding(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
TransportAddress *taddr, __be16 port,
struct nf_conntrack_expect *exp)
{
int dir = CTINFO2DIR(ctinfo);
u_int16_t nated_port;
/* Set expectations for NAT */
exp->saved_ip = exp->tuple.dst.u3.ip;
exp->tuple.dst.u3.ip = ct->tuplehash[!dir].tuple.dst.u3.ip;
exp->saved_proto.tcp.port = exp->tuple.dst.u.tcp.port;
exp->expectfn = ip_nat_callforwarding_expect;
exp->dir = !dir;
/* Try to get same port: if not, try to change it. */
for (nated_port = ntohs(port); nated_port != 0; nated_port++) {
exp->tuple.dst.u.tcp.port = htons(nated_port);
if (nf_conntrack_expect_related(exp) == 0)
break;
}
if (nated_port == 0) { /* No port available */
if (net_ratelimit())
printk("nf_nat_q931: out of TCP ports\n");
return 0;
}
/* Modify signal */
if (!set_h225_addr(pskb, data, dataoff, taddr,
&ct->tuplehash[!dir].tuple.dst.u3,
htons(nated_port)) == 0) {
nf_conntrack_unexpect_related(exp);
return -1;
}
/* Success */
DEBUGP("nf_nat_q931: expect Call Forwarding "
"%u.%u.%u.%u:%hu->%u.%u.%u.%u:%hu\n",
NIPQUAD(exp->tuple.src.ip), ntohs(exp->tuple.src.u.tcp.port),
NIPQUAD(exp->tuple.dst.ip), ntohs(exp->tuple.dst.u.tcp.port));
return 0;
}
/****************************************************************************/
static int __init init(void)
{
BUG_ON(rcu_dereference(set_h245_addr_hook) != NULL);
BUG_ON(rcu_dereference(set_h225_addr_hook) != NULL);
BUG_ON(rcu_dereference(set_sig_addr_hook) != NULL);
BUG_ON(rcu_dereference(set_ras_addr_hook) != NULL);
BUG_ON(rcu_dereference(nat_rtp_rtcp_hook) != NULL);
BUG_ON(rcu_dereference(nat_t120_hook) != NULL);
BUG_ON(rcu_dereference(nat_h245_hook) != NULL);
BUG_ON(rcu_dereference(nat_callforwarding_hook) != NULL);
BUG_ON(rcu_dereference(nat_q931_hook) != NULL);
rcu_assign_pointer(set_h245_addr_hook, set_h245_addr);
rcu_assign_pointer(set_h225_addr_hook, set_h225_addr);
rcu_assign_pointer(set_sig_addr_hook, set_sig_addr);
rcu_assign_pointer(set_ras_addr_hook, set_ras_addr);
rcu_assign_pointer(nat_rtp_rtcp_hook, nat_rtp_rtcp);
rcu_assign_pointer(nat_t120_hook, nat_t120);
rcu_assign_pointer(nat_h245_hook, nat_h245);
rcu_assign_pointer(nat_callforwarding_hook, nat_callforwarding);
rcu_assign_pointer(nat_q931_hook, nat_q931);
DEBUGP("nf_nat_h323: init success\n");
return 0;
}
/****************************************************************************/
static void __exit fini(void)
{
rcu_assign_pointer(set_h245_addr_hook, NULL);
rcu_assign_pointer(set_h225_addr_hook, NULL);
rcu_assign_pointer(set_sig_addr_hook, NULL);
rcu_assign_pointer(set_ras_addr_hook, NULL);
rcu_assign_pointer(nat_rtp_rtcp_hook, NULL);
rcu_assign_pointer(nat_t120_hook, NULL);
rcu_assign_pointer(nat_h245_hook, NULL);
rcu_assign_pointer(nat_callforwarding_hook, NULL);
rcu_assign_pointer(nat_q931_hook, NULL);
synchronize_rcu();
}
/****************************************************************************/
module_init(init);
module_exit(fini);
MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
MODULE_DESCRIPTION("H.323 NAT helper");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ip_nat_h323");
......@@ -160,6 +160,25 @@ config NF_CONNTRACK_FTP
To compile it as a module, choose M here. If unsure, say N.
config NF_CONNTRACK_H323
tristate "H.323 protocol support (EXPERIMENTAL)"
depends on EXPERIMENTAL && NF_CONNTRACK
help
H.323 is a VoIP signalling protocol from ITU-T. As one of the most
important VoIP protocols, it is widely used by voice hardware and
software including voice gateways, IP phones, Netmeeting, OpenPhone,
Gnomemeeting, etc.
With this module you can support H.323 on a connection tracking/NAT
firewall.
This module supports RAS, Fast Start, H.245 Tunnelling, Call
Forwarding, RTP/RTCP and T.120 based audio, video, fax, chat,
whiteboard, file transfer, etc. For more information, please
visit http://nath323.sourceforge.net/.
To compile it as a module, choose M here. If unsure, say N.
config NF_CT_NETLINK
tristate 'Connection tracking netlink interface (EXPERIMENTAL)'
depends on EXPERIMENTAL && NF_CONNTRACK && NETFILTER_NETLINK
......
......@@ -20,8 +20,11 @@ obj-$(CONFIG_NF_CT_PROTO_SCTP) += nf_conntrack_proto_sctp.o
obj-$(CONFIG_NF_CT_NETLINK) += nf_conntrack_netlink.o
# connection tracking helpers
nf_conntrack_h323-objs := nf_conntrack_h323_main.o nf_conntrack_h323_asn1.o
obj-$(CONFIG_NF_CONNTRACK_AMANDA) += nf_conntrack_amanda.o
obj-$(CONFIG_NF_CONNTRACK_FTP) += nf_conntrack_ftp.o
obj-$(CONFIG_NF_CONNTRACK_H323) += nf_conntrack_h323.o
# generic X tables
obj-$(CONFIG_NETFILTER_XTABLES) += x_tables.o xt_tcpudp.o
......
......@@ -15,7 +15,7 @@
#else
#include <stdio.h>
#endif
#include <linux/netfilter_ipv4/ip_conntrack_helper_h323_asn1.h>
#include <linux/netfilter/nf_conntrack_h323_asn1.h>
/* Trace Flag */
#ifndef H323_TRACE
......@@ -144,7 +144,7 @@ static decoder_t Decoders[] = {
/****************************************************************************
* H.323 Types
****************************************************************************/
#include "ip_conntrack_helper_h323_types.c"
#include "nf_conntrack_h323_types.c"
/****************************************************************************
* Functions
......
/*
* H.323 connection tracking helper
*
* Copyright (c) 2006 Jing Min Zhao <zhaojingmin@users.sourceforge.net>
*
* This source code is licensed under General Public License version 2.
*
* Based on the 'brute force' H.323 connection tracking module by
* Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
*
* For more information, please see http://nath323.sourceforge.net/
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/ctype.h>
#include <linux/inet.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/udp.h>
#include <linux/tcp.h>
#include <linux/skbuff.h>
#include <net/route.h>
#include <net/ip6_route.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack_tuple.h>
#include <net/netfilter/nf_conntrack_expect.h>
#include <net/netfilter/nf_conntrack_ecache.h>
#include <net/netfilter/nf_conntrack_helper.h>
#include <linux/netfilter/nf_conntrack_h323.h>
#if 0
#define DEBUGP printk
#else
#define DEBUGP(format, args...)
#endif
/* Parameters */
static unsigned int default_rrq_ttl __read_mostly = 300;
module_param(default_rrq_ttl, uint, 0600);
MODULE_PARM_DESC(default_rrq_ttl, "use this TTL if it's missing in RRQ");
static int gkrouted_only __read_mostly = 1;
module_param(gkrouted_only, int, 0600);
MODULE_PARM_DESC(gkrouted_only, "only accept calls from gatekeeper");
static int callforward_filter __read_mostly = 1;
module_param(callforward_filter, bool, 0600);
MODULE_PARM_DESC(callforward_filter, "only create call forwarding expectations "
"if both endpoints are on different sides "
"(determined by routing information)");
/* Hooks for NAT */
int (*set_h245_addr_hook) (struct sk_buff **pskb,
unsigned char **data, int dataoff,
H245_TransportAddress *taddr,
union nf_conntrack_address *addr, __be16 port)
__read_mostly;
int (*set_h225_addr_hook) (struct sk_buff **pskb,
unsigned char **data, int dataoff,
TransportAddress *taddr,
union nf_conntrack_address *addr, __be16 port)
__read_mostly;
int (*set_sig_addr_hook) (struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data,
TransportAddress *taddr, int count) __read_mostly;
int (*set_ras_addr_hook) (struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data,
TransportAddress *taddr, int count) __read_mostly;
int (*nat_rtp_rtcp_hook) (struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
H245_TransportAddress *taddr,
__be16 port, __be16 rtp_port,
struct nf_conntrack_expect *rtp_exp,
struct nf_conntrack_expect *rtcp_exp) __read_mostly;
int (*nat_t120_hook) (struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
H245_TransportAddress *taddr, __be16 port,
struct nf_conntrack_expect *exp) __read_mostly;
int (*nat_h245_hook) (struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
TransportAddress *taddr, __be16 port,
struct nf_conntrack_expect *exp) __read_mostly;
int (*nat_callforwarding_hook) (struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
TransportAddress *taddr, __be16 port,
struct nf_conntrack_expect *exp) __read_mostly;
int (*nat_q931_hook) (struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, TransportAddress *taddr, int idx,
__be16 port, struct nf_conntrack_expect *exp)
__read_mostly;
static DEFINE_SPINLOCK(nf_h323_lock);
static char *h323_buffer;
static struct nf_conntrack_helper nf_conntrack_helper_h245;
static struct nf_conntrack_helper nf_conntrack_helper_q931[];
static struct nf_conntrack_helper nf_conntrack_helper_ras[];
/****************************************************************************/
static int get_tpkt_data(struct sk_buff **pskb, unsigned int protoff,
struct nf_conn *ct, enum ip_conntrack_info ctinfo,
unsigned char **data, int *datalen, int *dataoff)
{
struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
int dir = CTINFO2DIR(ctinfo);
struct tcphdr _tcph, *th;
int tcpdatalen;
int tcpdataoff;
unsigned char *tpkt;
int tpktlen;
int tpktoff;
/* Get TCP header */
th = skb_header_pointer(*pskb, protoff, sizeof(_tcph), &_tcph);
if (th == NULL)
return 0;
/* Get TCP data offset */
tcpdataoff = protoff + th->doff * 4;
/* Get TCP data length */
tcpdatalen = (*pskb)->len - tcpdataoff;
if (tcpdatalen <= 0) /* No TCP data */
goto clear_out;
if (*data == NULL) { /* first TPKT */
/* Get first TPKT pointer */
tpkt = skb_header_pointer(*pskb, tcpdataoff, tcpdatalen,
h323_buffer);
BUG_ON(tpkt == NULL);
/* Validate TPKT identifier */
if (tcpdatalen < 4 || tpkt[0] != 0x03 || tpkt[1] != 0) {
/* Netmeeting sends TPKT header and data separately */
if (info->tpkt_len[dir] > 0) {
DEBUGP("nf_ct_h323: previous packet "
"indicated separate TPKT data of %hu "
"bytes\n", info->tpkt_len[dir]);
if (info->tpkt_len[dir] <= tcpdatalen) {
/* Yes, there was a TPKT header
* received */
*data = tpkt;
*datalen = info->tpkt_len[dir];
*dataoff = 0;
goto out;
}
/* Fragmented TPKT */
if (net_ratelimit())
printk("nf_ct_h323: "
"fragmented TPKT\n");
goto clear_out;
}
/* It is not even a TPKT */
return 0;
}
tpktoff = 0;
} else { /* Next TPKT */
tpktoff = *dataoff + *datalen;
tcpdatalen -= tpktoff;
if (tcpdatalen <= 4) /* No more TPKT */
goto clear_out;
tpkt = *data + *datalen;
/* Validate TPKT identifier */
if (tpkt[0] != 0x03 || tpkt[1] != 0)
goto clear_out;
}
/* Validate TPKT length */
tpktlen = tpkt[2] * 256 + tpkt[3];
if (tpktlen < 4)
goto clear_out;
if (tpktlen > tcpdatalen) {
if (tcpdatalen == 4) { /* Separate TPKT header */
/* Netmeeting sends TPKT header and data separately */
DEBUGP("nf_ct_h323: separate TPKT header indicates "
"there will be TPKT data of %hu bytes\n",
tpktlen - 4);
info->tpkt_len[dir] = tpktlen - 4;
return 0;
}
if (net_ratelimit())
printk("nf_ct_h323: incomplete TPKT (fragmented?)\n");
goto clear_out;
}
/* This is the encapsulated data */
*data = tpkt + 4;
*datalen = tpktlen - 4;
*dataoff = tpktoff + 4;
out:
/* Clear TPKT length */
info->tpkt_len[dir] = 0;
return 1;
clear_out:
info->tpkt_len[dir] = 0;
return 0;
}
/****************************************************************************/
static int get_h245_addr(struct nf_conn *ct, unsigned char *data,
H245_TransportAddress *taddr,
union nf_conntrack_address *addr, __be16 *port)
{
unsigned char *p;
int family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
int len;
if (taddr->choice != eH245_TransportAddress_unicastAddress)
return 0;
switch (taddr->unicastAddress.choice) {
case eUnicastAddress_iPAddress:
if (family != AF_INET)
return 0;
p = data + taddr->unicastAddress.iPAddress.network;
len = 4;
break;
case eUnicastAddress_iP6Address:
if (family != AF_INET6)
return 0;
p = data + taddr->unicastAddress.iP6Address.network;
len = 16;
break;
default:
return 0;
}
memcpy(addr, p, len);
memset((void *)addr + len, 0, sizeof(*addr) - len);
memcpy(port, p + len, sizeof(__be16));
return 1;
}
/****************************************************************************/
static int expect_rtp_rtcp(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
H245_TransportAddress *taddr)
{
int dir = CTINFO2DIR(ctinfo);
int ret = 0;
__be16 port;
__be16 rtp_port, rtcp_port;
union nf_conntrack_address addr;
struct nf_conntrack_expect *rtp_exp;
struct nf_conntrack_expect *rtcp_exp;
typeof(nat_rtp_rtcp_hook) nat_rtp_rtcp;
/* Read RTP or RTCP address */
if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
port == 0)
return 0;
/* RTP port is even */
port &= htons(~1);
rtp_port = port;
rtcp_port = htons(ntohs(port) + 1);
/* Create expect for RTP */
if ((rtp_exp = nf_conntrack_expect_alloc(ct)) == NULL)
return -1;
nf_conntrack_expect_init(rtp_exp, ct->tuplehash[!dir].tuple.src.l3num,
&ct->tuplehash[!dir].tuple.src.u3,
&ct->tuplehash[!dir].tuple.dst.u3,
IPPROTO_UDP, NULL, &rtp_port);
/* Create expect for RTCP */
if ((rtcp_exp = nf_conntrack_expect_alloc(ct)) == NULL) {
nf_conntrack_expect_put(rtp_exp);
return -1;
}
nf_conntrack_expect_init(rtcp_exp, ct->tuplehash[!dir].tuple.src.l3num,
&ct->tuplehash[!dir].tuple.src.u3,
&ct->tuplehash[!dir].tuple.dst.u3,
IPPROTO_UDP, NULL, &rtcp_port);
if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
&ct->tuplehash[!dir].tuple.dst.u3,
sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
(nat_rtp_rtcp = rcu_dereference(nat_rtp_rtcp_hook)) &&
ct->status & IPS_NAT_MASK) {
/* NAT needed */
ret = nat_rtp_rtcp(pskb, ct, ctinfo, data, dataoff,
taddr, port, rtp_port, rtp_exp, rtcp_exp);
} else { /* Conntrack only */
if (nf_conntrack_expect_related(rtp_exp) == 0) {
if (nf_conntrack_expect_related(rtcp_exp) == 0) {
DEBUGP("nf_ct_h323: expect RTP ");
NF_CT_DUMP_TUPLE(&rtp_exp->tuple);
DEBUGP("nf_ct_h323: expect RTCP ");
NF_CT_DUMP_TUPLE(&rtcp_exp->tuple);
} else {
nf_conntrack_unexpect_related(rtp_exp);
ret = -1;
}
} else
ret = -1;
}
nf_conntrack_expect_put(rtp_exp);
nf_conntrack_expect_put(rtcp_exp);
return ret;
}
/****************************************************************************/
static int expect_t120(struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
H245_TransportAddress *taddr)
{
int dir = CTINFO2DIR(ctinfo);
int ret = 0;
__be16 port;
union nf_conntrack_address addr;
struct nf_conntrack_expect *exp;
typeof(nat_t120_hook) nat_t120;
/* Read T.120 address */
if (!get_h245_addr(ct, *data, taddr, &addr, &port) ||
memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
port == 0)
return 0;
/* Create expect for T.120 connections */
if ((exp = nf_conntrack_expect_alloc(ct)) == NULL)
return -1;
nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
&ct->tuplehash[!dir].tuple.src.u3,
&ct->tuplehash[!dir].tuple.dst.u3,
IPPROTO_TCP, NULL, &port);
exp->flags = NF_CT_EXPECT_PERMANENT; /* Accept multiple channels */
if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
&ct->tuplehash[!dir].tuple.dst.u3,
sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
(nat_t120 = rcu_dereference(nat_t120_hook)) &&
ct->status & IPS_NAT_MASK) {
/* NAT needed */
ret = nat_t120(pskb, ct, ctinfo, data, dataoff, taddr,
port, exp);
} else { /* Conntrack only */
if (nf_conntrack_expect_related(exp) == 0) {
DEBUGP("nf_ct_h323: expect T.120 ");
NF_CT_DUMP_TUPLE(&exp->tuple);
} else
ret = -1;
}
nf_conntrack_expect_put(exp);
return ret;
}
/****************************************************************************/
static int process_h245_channel(struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
H2250LogicalChannelParameters *channel)
{
int ret;
if (channel->options & eH2250LogicalChannelParameters_mediaChannel) {
/* RTP */
ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff,
&channel->mediaChannel);
if (ret < 0)
return -1;
}
if (channel->
options & eH2250LogicalChannelParameters_mediaControlChannel) {
/* RTCP */
ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff,
&channel->mediaControlChannel);
if (ret < 0)
return -1;
}
return 0;
}
/****************************************************************************/
static int process_olc(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
OpenLogicalChannel *olc)
{
int ret;
DEBUGP("nf_ct_h323: OpenLogicalChannel\n");
if (olc->forwardLogicalChannelParameters.multiplexParameters.choice ==
eOpenLogicalChannel_forwardLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters)
{
ret = process_h245_channel(pskb, ct, ctinfo, data, dataoff,
&olc->
forwardLogicalChannelParameters.
multiplexParameters.
h2250LogicalChannelParameters);
if (ret < 0)
return -1;
}
if ((olc->options &
eOpenLogicalChannel_reverseLogicalChannelParameters) &&
(olc->reverseLogicalChannelParameters.options &
eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters)
&& (olc->reverseLogicalChannelParameters.multiplexParameters.
choice ==
eOpenLogicalChannel_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
{
ret =
process_h245_channel(pskb, ct, ctinfo, data, dataoff,
&olc->
reverseLogicalChannelParameters.
multiplexParameters.
h2250LogicalChannelParameters);
if (ret < 0)
return -1;
}
if ((olc->options & eOpenLogicalChannel_separateStack) &&
olc->forwardLogicalChannelParameters.dataType.choice ==
eDataType_data &&
olc->forwardLogicalChannelParameters.dataType.data.application.
choice == eDataApplicationCapability_application_t120 &&
olc->forwardLogicalChannelParameters.dataType.data.application.
t120.choice == eDataProtocolCapability_separateLANStack &&
olc->separateStack.networkAddress.choice ==
eNetworkAccessParameters_networkAddress_localAreaAddress) {
ret = expect_t120(pskb, ct, ctinfo, data, dataoff,
&olc->separateStack.networkAddress.
localAreaAddress);
if (ret < 0)
return -1;
}
return 0;
}
/****************************************************************************/
static int process_olca(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
OpenLogicalChannelAck *olca)
{
H2250LogicalChannelAckParameters *ack;
int ret;
DEBUGP("nf_ct_h323: OpenLogicalChannelAck\n");
if ((olca->options &
eOpenLogicalChannelAck_reverseLogicalChannelParameters) &&
(olca->reverseLogicalChannelParameters.options &
eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters)
&& (olca->reverseLogicalChannelParameters.multiplexParameters.
choice ==
eOpenLogicalChannelAck_reverseLogicalChannelParameters_multiplexParameters_h2250LogicalChannelParameters))
{
ret = process_h245_channel(pskb, ct, ctinfo, data, dataoff,
&olca->
reverseLogicalChannelParameters.
multiplexParameters.
h2250LogicalChannelParameters);
if (ret < 0)
return -1;
}
if ((olca->options &
eOpenLogicalChannelAck_forwardMultiplexAckParameters) &&
(olca->forwardMultiplexAckParameters.choice ==
eOpenLogicalChannelAck_forwardMultiplexAckParameters_h2250LogicalChannelAckParameters))
{
ack = &olca->forwardMultiplexAckParameters.
h2250LogicalChannelAckParameters;
if (ack->options &
eH2250LogicalChannelAckParameters_mediaChannel) {
/* RTP */
ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff,
&ack->mediaChannel);
if (ret < 0)
return -1;
}
if (ack->options &
eH2250LogicalChannelAckParameters_mediaControlChannel) {
/* RTCP */
ret = expect_rtp_rtcp(pskb, ct, ctinfo, data, dataoff,
&ack->mediaControlChannel);
if (ret < 0)
return -1;
}
}
return 0;
}
/****************************************************************************/
static int process_h245(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
MultimediaSystemControlMessage *mscm)
{
switch (mscm->choice) {
case eMultimediaSystemControlMessage_request:
if (mscm->request.choice ==
eRequestMessage_openLogicalChannel) {
return process_olc(pskb, ct, ctinfo, data, dataoff,
&mscm->request.openLogicalChannel);
}
DEBUGP("nf_ct_h323: H.245 Request %d\n",
mscm->request.choice);
break;
case eMultimediaSystemControlMessage_response:
if (mscm->response.choice ==
eResponseMessage_openLogicalChannelAck) {
return process_olca(pskb, ct, ctinfo, data, dataoff,
&mscm->response.
openLogicalChannelAck);
}
DEBUGP("nf_ct_h323: H.245 Response %d\n",
mscm->response.choice);
break;
default:
DEBUGP("nf_ct_h323: H.245 signal %d\n", mscm->choice);
break;
}
return 0;
}
/****************************************************************************/
static int h245_help(struct sk_buff **pskb, unsigned int protoff,
struct nf_conn *ct, enum ip_conntrack_info ctinfo)
{
static MultimediaSystemControlMessage mscm;
unsigned char *data = NULL;
int datalen;
int dataoff;
int ret;
/* 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) {
return NF_ACCEPT;
}
DEBUGP("nf_ct_h245: skblen = %u\n", (*pskb)->len);
spin_lock_bh(&nf_h323_lock);
/* Process each TPKT */
while (get_tpkt_data(pskb, protoff, ct, ctinfo,
&data, &datalen, &dataoff)) {
DEBUGP("nf_ct_h245: TPKT len=%d ", datalen);
NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
/* Decode H.245 signal */
ret = DecodeMultimediaSystemControlMessage(data, datalen,
&mscm);
if (ret < 0) {
if (net_ratelimit())
printk("nf_ct_h245: decoding error: %s\n",
ret == H323_ERROR_BOUND ?
"out of bound" : "out of range");
/* We don't drop when decoding error */
break;
}
/* Process H.245 signal */
if (process_h245(pskb, ct, ctinfo, &data, dataoff, &mscm) < 0)
goto drop;
}
spin_unlock_bh(&nf_h323_lock);
return NF_ACCEPT;
drop:
spin_unlock_bh(&nf_h323_lock);
if (net_ratelimit())
printk("nf_ct_h245: packet dropped\n");
return NF_DROP;
}
/****************************************************************************/
static struct nf_conntrack_helper nf_conntrack_helper_h245 __read_mostly = {
.name = "H.245",
.me = THIS_MODULE,
.max_expected = H323_RTP_CHANNEL_MAX * 4 + 2 /* T.120 */,
.timeout = 240,
.tuple.dst.protonum = IPPROTO_UDP,
.mask.src.u.udp.port = __constant_htons(0xFFFF),
.mask.dst.protonum = 0xFF,
.help = h245_help
};
/****************************************************************************/
int get_h225_addr(struct nf_conn *ct, unsigned char *data,
TransportAddress *taddr,
union nf_conntrack_address *addr, __be16 *port)
{
unsigned char *p;
int family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
int len;
switch (taddr->choice) {
case eTransportAddress_ipAddress:
if (family != AF_INET)
return 0;
p = data + taddr->ipAddress.ip;
len = 4;
break;
case eTransportAddress_ip6Address:
if (family != AF_INET6)
return 0;
p = data + taddr->ip6Address.ip6;
len = 16;
break;
default:
return 0;
}
memcpy(addr, p, len);
memset((void *)addr + len, 0, sizeof(*addr) - len);
memcpy(port, p + len, sizeof(__be16));
return 1;
}
/****************************************************************************/
static int expect_h245(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
TransportAddress *taddr)
{
int dir = CTINFO2DIR(ctinfo);
int ret = 0;
__be16 port;
union nf_conntrack_address addr;
struct nf_conntrack_expect *exp;
typeof(nat_h245_hook) nat_h245;
/* Read h245Address */
if (!get_h225_addr(ct, *data, taddr, &addr, &port) ||
memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) ||
port == 0)
return 0;
/* Create expect for h245 connection */
if ((exp = nf_conntrack_expect_alloc(ct)) == NULL)
return -1;
nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
&ct->tuplehash[!dir].tuple.src.u3,
&ct->tuplehash[!dir].tuple.dst.u3,
IPPROTO_TCP, NULL, &port);
exp->helper = &nf_conntrack_helper_h245;
if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
&ct->tuplehash[!dir].tuple.dst.u3,
sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
(nat_h245 = rcu_dereference(nat_h245_hook)) &&
ct->status & IPS_NAT_MASK) {
/* NAT needed */
ret = nat_h245(pskb, ct, ctinfo, data, dataoff, taddr,
port, exp);
} else { /* Conntrack only */
if (nf_conntrack_expect_related(exp) == 0) {
DEBUGP("nf_ct_q931: expect H.245 ");
NF_CT_DUMP_TUPLE(&exp->tuple);
} else
ret = -1;
}
nf_conntrack_expect_put(exp);
return ret;
}
/* If the calling party is on the same side of the forward-to party,
* we don't need to track the second call */
static int callforward_do_filter(union nf_conntrack_address *src,
union nf_conntrack_address *dst,
int family)
{
struct flowi fl1, fl2;
int ret = 0;
memset(&fl1, 0, sizeof(fl1));
memset(&fl2, 0, sizeof(fl2));
switch (family) {
case AF_INET: {
struct rtable *rt1, *rt2;
fl1.fl4_dst = src->ip;
fl2.fl4_dst = dst->ip;
if (ip_route_output_key(&rt1, &fl1) == 0) {
if (ip_route_output_key(&rt2, &fl2) == 0) {
if (rt1->rt_gateway == rt2->rt_gateway &&
rt1->u.dst.dev == rt2->u.dst.dev)
ret = 1;
dst_release(&rt2->u.dst);
}
dst_release(&rt1->u.dst);
}
break;
}
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
case AF_INET6: {
struct rt6_info *rt1, *rt2;
memcpy(&fl1.fl6_dst, src, sizeof(fl1.fl6_dst));
memcpy(&fl2.fl6_dst, dst, sizeof(fl2.fl6_dst));
rt1 = (struct rt6_info *)ip6_route_output(NULL, &fl1);
if (rt1) {
rt2 = (struct rt6_info *)ip6_route_output(NULL, &fl2);
if (rt2) {
if (!memcmp(&rt1->rt6i_gateway, &rt2->rt6i_gateway,
sizeof(rt1->rt6i_gateway)) &&
rt1->u.dst.dev == rt2->u.dst.dev)
ret = 1;
dst_release(&rt2->u.dst);
}
dst_release(&rt1->u.dst);
}
break;
}
#endif
}
return ret;
}
/****************************************************************************/
static int expect_callforwarding(struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
TransportAddress *taddr)
{
int dir = CTINFO2DIR(ctinfo);
int ret = 0;
__be16 port;
union nf_conntrack_address addr;
struct nf_conntrack_expect *exp;
typeof(nat_callforwarding_hook) nat_callforwarding;
/* Read alternativeAddress */
if (!get_h225_addr(ct, *data, taddr, &addr, &port) || port == 0)
return 0;
/* If the calling party is on the same side of the forward-to party,
* we don't need to track the second call */
if (callforward_filter &&
callforward_do_filter(&addr, &ct->tuplehash[!dir].tuple.src.u3,
ct->tuplehash[!dir].tuple.src.l3num)) {
DEBUGP("nf_ct_q931: Call Forwarding not tracked\n");
return 0;
}
/* Create expect for the second call leg */
if ((exp = nf_conntrack_expect_alloc(ct)) == NULL)
return -1;
nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
&ct->tuplehash[!dir].tuple.src.u3, &addr,
IPPROTO_TCP, NULL, &port);
exp->helper = nf_conntrack_helper_q931;
if (memcmp(&ct->tuplehash[dir].tuple.src.u3,
&ct->tuplehash[!dir].tuple.dst.u3,
sizeof(ct->tuplehash[dir].tuple.src.u3)) &&
(nat_callforwarding = rcu_dereference(nat_callforwarding_hook)) &&
ct->status & IPS_NAT_MASK) {
/* Need NAT */
ret = nat_callforwarding(pskb, ct, ctinfo, data, dataoff,
taddr, port, exp);
} else { /* Conntrack only */
if (nf_conntrack_expect_related(exp) == 0) {
DEBUGP("nf_ct_q931: expect Call Forwarding ");
NF_CT_DUMP_TUPLE(&exp->tuple);
} else
ret = -1;
}
nf_conntrack_expect_put(exp);
return ret;
}
/****************************************************************************/
static int process_setup(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
Setup_UUIE *setup)
{
int dir = CTINFO2DIR(ctinfo);
int ret;
int i;
__be16 port;
union nf_conntrack_address addr;
typeof(set_h225_addr_hook) set_h225_addr;
DEBUGP("nf_ct_q931: Setup\n");
if (setup->options & eSetup_UUIE_h245Address) {
ret = expect_h245(pskb, ct, ctinfo, data, dataoff,
&setup->h245Address);
if (ret < 0)
return -1;
}
set_h225_addr = rcu_dereference(set_h225_addr_hook);
if ((setup->options & eSetup_UUIE_destCallSignalAddress) &&
(set_h225_addr) && ct->status && IPS_NAT_MASK &&
get_h225_addr(ct, *data, &setup->destCallSignalAddress,
&addr, &port) &&
memcmp(&addr, &ct->tuplehash[!dir].tuple.src.u3, sizeof(addr))) {
DEBUGP("nf_ct_q931: set destCallSignalAddress "
NIP6_FMT ":%hu->" NIP6_FMT ":%hu\n",
NIP6(*(struct in6_addr *)&addr), ntohs(port),
NIP6(*(struct in6_addr *)&ct->tuplehash[!dir].tuple.src.u3),
ntohs(ct->tuplehash[!dir].tuple.src.u.tcp.port));
ret = set_h225_addr(pskb, data, dataoff,
&setup->destCallSignalAddress,
&ct->tuplehash[!dir].tuple.src.u3,
ct->tuplehash[!dir].tuple.src.u.tcp.port);
if (ret < 0)
return -1;
}
if ((setup->options & eSetup_UUIE_sourceCallSignalAddress) &&
(set_h225_addr) && ct->status & IPS_NAT_MASK &&
get_h225_addr(ct, *data, &setup->sourceCallSignalAddress,
&addr, &port) &&
memcmp(&addr, &ct->tuplehash[!dir].tuple.dst.u3, sizeof(addr))) {
DEBUGP("nf_ct_q931: set sourceCallSignalAddress "
NIP6_FMT ":%hu->" NIP6_FMT ":%hu\n",
NIP6(*(struct in6_addr *)&addr), ntohs(port),
NIP6(*(struct in6_addr *)&ct->tuplehash[!dir].tuple.dst.u3),
ntohs(ct->tuplehash[!dir].tuple.dst.u.tcp.port));
ret = set_h225_addr(pskb, data, dataoff,
&setup->sourceCallSignalAddress,
&ct->tuplehash[!dir].tuple.dst.u3,
ct->tuplehash[!dir].tuple.dst.u.tcp.port);
if (ret < 0)
return -1;
}
if (setup->options & eSetup_UUIE_fastStart) {
for (i = 0; i < setup->fastStart.count; i++) {
ret = process_olc(pskb, ct, ctinfo, data, dataoff,
&setup->fastStart.item[i]);
if (ret < 0)
return -1;
}
}
return 0;
}
/****************************************************************************/
static int process_callproceeding(struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
CallProceeding_UUIE *callproc)
{
int ret;
int i;
DEBUGP("nf_ct_q931: CallProceeding\n");
if (callproc->options & eCallProceeding_UUIE_h245Address) {
ret = expect_h245(pskb, ct, ctinfo, data, dataoff,
&callproc->h245Address);
if (ret < 0)
return -1;
}
if (callproc->options & eCallProceeding_UUIE_fastStart) {
for (i = 0; i < callproc->fastStart.count; i++) {
ret = process_olc(pskb, ct, ctinfo, data, dataoff,
&callproc->fastStart.item[i]);
if (ret < 0)
return -1;
}
}
return 0;
}
/****************************************************************************/
static int process_connect(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
Connect_UUIE *connect)
{
int ret;
int i;
DEBUGP("nf_ct_q931: Connect\n");
if (connect->options & eConnect_UUIE_h245Address) {
ret = expect_h245(pskb, ct, ctinfo, data, dataoff,
&connect->h245Address);
if (ret < 0)
return -1;
}
if (connect->options & eConnect_UUIE_fastStart) {
for (i = 0; i < connect->fastStart.count; i++) {
ret = process_olc(pskb, ct, ctinfo, data, dataoff,
&connect->fastStart.item[i]);
if (ret < 0)
return -1;
}
}
return 0;
}
/****************************************************************************/
static int process_alerting(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
Alerting_UUIE *alert)
{
int ret;
int i;
DEBUGP("nf_ct_q931: Alerting\n");
if (alert->options & eAlerting_UUIE_h245Address) {
ret = expect_h245(pskb, ct, ctinfo, data, dataoff,
&alert->h245Address);
if (ret < 0)
return -1;
}
if (alert->options & eAlerting_UUIE_fastStart) {
for (i = 0; i < alert->fastStart.count; i++) {
ret = process_olc(pskb, ct, ctinfo, data, dataoff,
&alert->fastStart.item[i]);
if (ret < 0)
return -1;
}
}
return 0;
}
/****************************************************************************/
static int process_information(struct sk_buff **pskb,
struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
Information_UUIE *info)
{
int ret;
int i;
DEBUGP("nf_ct_q931: Information\n");
if (info->options & eInformation_UUIE_fastStart) {
for (i = 0; i < info->fastStart.count; i++) {
ret = process_olc(pskb, ct, ctinfo, data, dataoff,
&info->fastStart.item[i]);
if (ret < 0)
return -1;
}
}
return 0;
}
/****************************************************************************/
static int process_facility(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
Facility_UUIE *facility)
{
int ret;
int i;
DEBUGP("nf_ct_q931: Facility\n");
if (facility->reason.choice == eFacilityReason_callForwarded) {
if (facility->options & eFacility_UUIE_alternativeAddress)
return expect_callforwarding(pskb, ct, ctinfo, data,
dataoff,
&facility->
alternativeAddress);
return 0;
}
if (facility->options & eFacility_UUIE_h245Address) {
ret = expect_h245(pskb, ct, ctinfo, data, dataoff,
&facility->h245Address);
if (ret < 0)
return -1;
}
if (facility->options & eFacility_UUIE_fastStart) {
for (i = 0; i < facility->fastStart.count; i++) {
ret = process_olc(pskb, ct, ctinfo, data, dataoff,
&facility->fastStart.item[i]);
if (ret < 0)
return -1;
}
}
return 0;
}
/****************************************************************************/
static int process_progress(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff,
Progress_UUIE *progress)
{
int ret;
int i;
DEBUGP("nf_ct_q931: Progress\n");
if (progress->options & eProgress_UUIE_h245Address) {
ret = expect_h245(pskb, ct, ctinfo, data, dataoff,
&progress->h245Address);
if (ret < 0)
return -1;
}
if (progress->options & eProgress_UUIE_fastStart) {
for (i = 0; i < progress->fastStart.count; i++) {
ret = process_olc(pskb, ct, ctinfo, data, dataoff,
&progress->fastStart.item[i]);
if (ret < 0)
return -1;
}
}
return 0;
}
/****************************************************************************/
static int process_q931(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, int dataoff, Q931 *q931)
{
H323_UU_PDU *pdu = &q931->UUIE.h323_uu_pdu;
int i;
int ret = 0;
switch (pdu->h323_message_body.choice) {
case eH323_UU_PDU_h323_message_body_setup:
ret = process_setup(pskb, ct, ctinfo, data, dataoff,
&pdu->h323_message_body.setup);
break;
case eH323_UU_PDU_h323_message_body_callProceeding:
ret = process_callproceeding(pskb, ct, ctinfo, data, dataoff,
&pdu->h323_message_body.
callProceeding);
break;
case eH323_UU_PDU_h323_message_body_connect:
ret = process_connect(pskb, ct, ctinfo, data, dataoff,
&pdu->h323_message_body.connect);
break;
case eH323_UU_PDU_h323_message_body_alerting:
ret = process_alerting(pskb, ct, ctinfo, data, dataoff,
&pdu->h323_message_body.alerting);
break;
case eH323_UU_PDU_h323_message_body_information:
ret = process_information(pskb, ct, ctinfo, data, dataoff,
&pdu->h323_message_body.
information);
break;
case eH323_UU_PDU_h323_message_body_facility:
ret = process_facility(pskb, ct, ctinfo, data, dataoff,
&pdu->h323_message_body.facility);
break;
case eH323_UU_PDU_h323_message_body_progress:
ret = process_progress(pskb, ct, ctinfo, data, dataoff,
&pdu->h323_message_body.progress);
break;
default:
DEBUGP("nf_ct_q931: Q.931 signal %d\n",
pdu->h323_message_body.choice);
break;
}
if (ret < 0)
return -1;
if (pdu->options & eH323_UU_PDU_h245Control) {
for (i = 0; i < pdu->h245Control.count; i++) {
ret = process_h245(pskb, ct, ctinfo, data, dataoff,
&pdu->h245Control.item[i]);
if (ret < 0)
return -1;
}
}
return 0;
}
/****************************************************************************/
static int q931_help(struct sk_buff **pskb, unsigned int protoff,
struct nf_conn *ct, enum ip_conntrack_info ctinfo)
{
static Q931 q931;
unsigned char *data = NULL;
int datalen;
int dataoff;
int ret;
/* 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) {
return NF_ACCEPT;
}
DEBUGP("nf_ct_q931: skblen = %u\n", (*pskb)->len);
spin_lock_bh(&nf_h323_lock);
/* Process each TPKT */
while (get_tpkt_data(pskb, protoff, ct, ctinfo,
&data, &datalen, &dataoff)) {
DEBUGP("nf_ct_q931: TPKT len=%d ", datalen);
NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
/* Decode Q.931 signal */
ret = DecodeQ931(data, datalen, &q931);
if (ret < 0) {
if (net_ratelimit())
printk("nf_ct_q931: decoding error: %s\n",
ret == H323_ERROR_BOUND ?
"out of bound" : "out of range");
/* We don't drop when decoding error */
break;
}
/* Process Q.931 signal */
if (process_q931(pskb, ct, ctinfo, &data, dataoff, &q931) < 0)
goto drop;
}
spin_unlock_bh(&nf_h323_lock);
return NF_ACCEPT;
drop:
spin_unlock_bh(&nf_h323_lock);
if (net_ratelimit())
printk("nf_ct_q931: packet dropped\n");
return NF_DROP;
}
/****************************************************************************/
static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
{
.name = "Q.931",
.me = THIS_MODULE,
/* T.120 and H.245 */
.max_expected = H323_RTP_CHANNEL_MAX * 4 + 4,
.timeout = 240,
.tuple.src.l3num = AF_INET,
.tuple.src.u.tcp.port = __constant_htons(Q931_PORT),
.tuple.dst.protonum = IPPROTO_TCP,
.mask.src.l3num = 0xFFFF,
.mask.src.u.tcp.port = __constant_htons(0xFFFF),
.mask.dst.protonum = 0xFF,
.help = q931_help
},
{
.name = "Q.931",
.me = THIS_MODULE,
/* T.120 and H.245 */
.max_expected = H323_RTP_CHANNEL_MAX * 4 + 4,
.timeout = 240,
.tuple.src.l3num = AF_INET6,
.tuple.src.u.tcp.port = __constant_htons(Q931_PORT),
.tuple.dst.protonum = IPPROTO_TCP,
.mask.src.l3num = 0xFFFF,
.mask.src.u.tcp.port = __constant_htons(0xFFFF),
.mask.dst.protonum = 0xFF,
.help = q931_help
},
};
/****************************************************************************/
static unsigned char *get_udp_data(struct sk_buff **pskb, unsigned int protoff,
int *datalen)
{
struct udphdr _uh, *uh;
int dataoff;
uh = skb_header_pointer(*pskb, protoff, sizeof(_uh), &_uh);
if (uh == NULL)
return NULL;
dataoff = protoff + sizeof(_uh);
if (dataoff >= (*pskb)->len)
return NULL;
*datalen = (*pskb)->len - dataoff;
return skb_header_pointer(*pskb, dataoff, *datalen, h323_buffer);
}
/****************************************************************************/
static struct nf_conntrack_expect *find_expect(struct nf_conn *ct,
union nf_conntrack_address *addr,
__be16 port)
{
struct nf_conntrack_expect *exp;
struct nf_conntrack_tuple tuple;
memset(&tuple.src.u3, 0, sizeof(tuple.src.u3));
tuple.src.u.tcp.port = 0;
memcpy(&tuple.dst.u3, addr, sizeof(tuple.dst.u3));
tuple.dst.u.tcp.port = port;
tuple.dst.protonum = IPPROTO_TCP;
exp = __nf_conntrack_expect_find(&tuple);
if (exp && exp->master == ct)
return exp;
return NULL;
}
/****************************************************************************/
static int set_expect_timeout(struct nf_conntrack_expect *exp,
unsigned timeout)
{
if (!exp || !del_timer(&exp->timeout))
return 0;
exp->timeout.expires = jiffies + timeout * HZ;
add_timer(&exp->timeout);
return 1;
}
/****************************************************************************/
static int expect_q931(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data,
TransportAddress *taddr, int count)
{
struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
int dir = CTINFO2DIR(ctinfo);
int ret = 0;
int i;
__be16 port;
union nf_conntrack_address addr;
struct nf_conntrack_expect *exp;
typeof(nat_q931_hook) nat_q931;
/* Look for the first related address */
for (i = 0; i < count; i++) {
if (get_h225_addr(ct, *data, &taddr[i], &addr, &port) &&
memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3,
sizeof(addr)) == 0 && port != 0)
break;
}
if (i >= count) /* Not found */
return 0;
/* Create expect for Q.931 */
if ((exp = nf_conntrack_expect_alloc(ct)) == NULL)
return -1;
nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
gkrouted_only ? /* only accept calls from GK? */
&ct->tuplehash[!dir].tuple.src.u3 :
NULL,
&ct->tuplehash[!dir].tuple.dst.u3,
IPPROTO_TCP, NULL, &port);
exp->helper = nf_conntrack_helper_q931;
exp->flags = NF_CT_EXPECT_PERMANENT; /* Accept multiple calls */
nat_q931 = rcu_dereference(nat_q931_hook);
if (nat_q931 && ct->status & IPS_NAT_MASK) { /* Need NAT */
ret = nat_q931(pskb, ct, ctinfo, data, taddr, i, port, exp);
} else { /* Conntrack only */
if (nf_conntrack_expect_related(exp) == 0) {
DEBUGP("nf_ct_ras: expect Q.931 ");
NF_CT_DUMP_TUPLE(&exp->tuple);
/* Save port for looking up expect in processing RCF */
info->sig_port[dir] = port;
} else
ret = -1;
}
nf_conntrack_expect_put(exp);
return ret;
}
/****************************************************************************/
static int process_grq(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, GatekeeperRequest *grq)
{
typeof(set_ras_addr_hook) set_ras_addr;
DEBUGP("nf_ct_ras: GRQ\n");
set_ras_addr = rcu_dereference(set_ras_addr_hook);
if (set_ras_addr && ct->status & IPS_NAT_MASK) /* NATed */
return set_ras_addr(pskb, ct, ctinfo, data,
&grq->rasAddress, 1);
return 0;
}
/****************************************************************************/
static int process_gcf(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, GatekeeperConfirm *gcf)
{
int dir = CTINFO2DIR(ctinfo);
int ret = 0;
__be16 port;
union nf_conntrack_address addr;
struct nf_conntrack_expect *exp;
DEBUGP("nf_ct_ras: GCF\n");
if (!get_h225_addr(ct, *data, &gcf->rasAddress, &addr, &port))
return 0;
/* Registration port is the same as discovery port */
if (!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
port == ct->tuplehash[dir].tuple.src.u.udp.port)
return 0;
/* Avoid RAS expectation loops. A GCF is never expected. */
if (test_bit(IPS_EXPECTED_BIT, &ct->status))
return 0;
/* Need new expect */
if ((exp = nf_conntrack_expect_alloc(ct)) == NULL)
return -1;
nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
&ct->tuplehash[!dir].tuple.src.u3, &addr,
IPPROTO_UDP, NULL, &port);
exp->helper = nf_conntrack_helper_ras;
if (nf_conntrack_expect_related(exp) == 0) {
DEBUGP("nf_ct_ras: expect RAS ");
NF_CT_DUMP_TUPLE(&exp->tuple);
} else
ret = -1;
nf_conntrack_expect_put(exp);
return ret;
}
/****************************************************************************/
static int process_rrq(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, RegistrationRequest *rrq)
{
struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
int ret;
typeof(set_ras_addr_hook) set_ras_addr;
DEBUGP("nf_ct_ras: RRQ\n");
ret = expect_q931(pskb, ct, ctinfo, data,
rrq->callSignalAddress.item,
rrq->callSignalAddress.count);
if (ret < 0)
return -1;
set_ras_addr = rcu_dereference(set_ras_addr_hook);
if (set_ras_addr && ct->status & IPS_NAT_MASK) {
ret = set_ras_addr(pskb, ct, ctinfo, data,
rrq->rasAddress.item,
rrq->rasAddress.count);
if (ret < 0)
return -1;
}
if (rrq->options & eRegistrationRequest_timeToLive) {
DEBUGP("nf_ct_ras: RRQ TTL = %u seconds\n", rrq->timeToLive);
info->timeout = rrq->timeToLive;
} else
info->timeout = default_rrq_ttl;
return 0;
}
/****************************************************************************/
static int process_rcf(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, RegistrationConfirm *rcf)
{
struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
int dir = CTINFO2DIR(ctinfo);
int ret;
struct nf_conntrack_expect *exp;
typeof(set_sig_addr_hook) set_sig_addr;
DEBUGP("nf_ct_ras: RCF\n");
set_sig_addr = rcu_dereference(set_sig_addr_hook);
if (set_sig_addr && ct->status & IPS_NAT_MASK) {
ret = set_sig_addr(pskb, ct, ctinfo, data,
rcf->callSignalAddress.item,
rcf->callSignalAddress.count);
if (ret < 0)
return -1;
}
if (rcf->options & eRegistrationConfirm_timeToLive) {
DEBUGP("nf_ct_ras: RCF TTL = %u seconds\n", rcf->timeToLive);
info->timeout = rcf->timeToLive;
}
if (info->timeout > 0) {
DEBUGP
("nf_ct_ras: set RAS connection timeout to %u seconds\n",
info->timeout);
nf_ct_refresh(ct, *pskb, info->timeout * HZ);
/* Set expect timeout */
read_lock_bh(&nf_conntrack_lock);
exp = find_expect(ct, &ct->tuplehash[dir].tuple.dst.u3,
info->sig_port[!dir]);
if (exp) {
DEBUGP("nf_ct_ras: set Q.931 expect "
"timeout to %u seconds for",
info->timeout);
NF_CT_DUMP_TUPLE(&exp->tuple);
set_expect_timeout(exp, info->timeout);
}
read_unlock_bh(&nf_conntrack_lock);
}
return 0;
}
/****************************************************************************/
static int process_urq(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, UnregistrationRequest *urq)
{
struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
int dir = CTINFO2DIR(ctinfo);
int ret;
typeof(set_sig_addr_hook) set_sig_addr;
DEBUGP("nf_ct_ras: URQ\n");
set_sig_addr = rcu_dereference(set_sig_addr_hook);
if (set_sig_addr && ct->status & IPS_NAT_MASK) {
ret = set_sig_addr(pskb, ct, ctinfo, data,
urq->callSignalAddress.item,
urq->callSignalAddress.count);
if (ret < 0)
return -1;
}
/* Clear old expect */
nf_ct_remove_expectations(ct);
info->sig_port[dir] = 0;
info->sig_port[!dir] = 0;
/* Give it 30 seconds for UCF or URJ */
nf_ct_refresh(ct, *pskb, 30 * HZ);
return 0;
}
/****************************************************************************/
static int process_arq(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, AdmissionRequest *arq)
{
struct nf_ct_h323_master *info = &nfct_help(ct)->help.ct_h323_info;
int dir = CTINFO2DIR(ctinfo);
__be16 port;
union nf_conntrack_address addr;
typeof(set_h225_addr_hook) set_h225_addr;
DEBUGP("nf_ct_ras: ARQ\n");
set_h225_addr = rcu_dereference(set_h225_addr_hook);
if ((arq->options & eAdmissionRequest_destCallSignalAddress) &&
get_h225_addr(ct, *data, &arq->destCallSignalAddress,
&addr, &port) &&
!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
port == info->sig_port[dir] &&
set_h225_addr && ct->status & IPS_NAT_MASK) {
/* Answering ARQ */
return set_h225_addr(pskb, data, 0,
&arq->destCallSignalAddress,
&ct->tuplehash[!dir].tuple.dst.u3,
info->sig_port[!dir]);
}
if ((arq->options & eAdmissionRequest_srcCallSignalAddress) &&
get_h225_addr(ct, *data, &arq->srcCallSignalAddress,
&addr, &port) &&
!memcmp(&addr, &ct->tuplehash[dir].tuple.src.u3, sizeof(addr)) &&
set_h225_addr && ct->status & IPS_NAT_MASK) {
/* Calling ARQ */
return set_h225_addr(pskb, data, 0,
&arq->srcCallSignalAddress,
&ct->tuplehash[!dir].tuple.dst.u3,
port);
}
return 0;
}
/****************************************************************************/
static int process_acf(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, AdmissionConfirm *acf)
{
int dir = CTINFO2DIR(ctinfo);
int ret = 0;
__be16 port;
union nf_conntrack_address addr;
struct nf_conntrack_expect *exp;
typeof(set_sig_addr_hook) set_sig_addr;
DEBUGP("nf_ct_ras: ACF\n");
if (!get_h225_addr(ct, *data, &acf->destCallSignalAddress,
&addr, &port))
return 0;
if (!memcmp(&addr, &ct->tuplehash[dir].tuple.dst.u3, sizeof(addr))) {
/* Answering ACF */
set_sig_addr = rcu_dereference(set_sig_addr_hook);
if (set_sig_addr && ct->status & IPS_NAT_MASK)
return set_sig_addr(pskb, ct, ctinfo, data,
&acf->destCallSignalAddress, 1);
return 0;
}
/* Need new expect */
if ((exp = nf_conntrack_expect_alloc(ct)) == NULL)
return -1;
nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
&ct->tuplehash[!dir].tuple.src.u3, &addr,
IPPROTO_TCP, NULL, &port);
exp->flags = NF_CT_EXPECT_PERMANENT;
exp->helper = nf_conntrack_helper_q931;
if (nf_conntrack_expect_related(exp) == 0) {
DEBUGP("nf_ct_ras: expect Q.931 ");
NF_CT_DUMP_TUPLE(&exp->tuple);
} else
ret = -1;
nf_conntrack_expect_put(exp);
return ret;
}
/****************************************************************************/
static int process_lrq(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, LocationRequest *lrq)
{
typeof(set_ras_addr_hook) set_ras_addr;
DEBUGP("nf_ct_ras: LRQ\n");
set_ras_addr = rcu_dereference(set_ras_addr_hook);
if (set_ras_addr && ct->status & IPS_NAT_MASK)
return set_ras_addr(pskb, ct, ctinfo, data,
&lrq->replyAddress, 1);
return 0;
}
/****************************************************************************/
static int process_lcf(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, LocationConfirm *lcf)
{
int dir = CTINFO2DIR(ctinfo);
int ret = 0;
__be16 port;
union nf_conntrack_address addr;
struct nf_conntrack_expect *exp;
DEBUGP("nf_ct_ras: LCF\n");
if (!get_h225_addr(ct, *data, &lcf->callSignalAddress,
&addr, &port))
return 0;
/* Need new expect for call signal */
if ((exp = nf_conntrack_expect_alloc(ct)) == NULL)
return -1;
nf_conntrack_expect_init(exp, ct->tuplehash[!dir].tuple.src.l3num,
&ct->tuplehash[!dir].tuple.src.u3, &addr,
IPPROTO_TCP, NULL, &port);
exp->flags = NF_CT_EXPECT_PERMANENT;
exp->helper = nf_conntrack_helper_q931;
if (nf_conntrack_expect_related(exp) == 0) {
DEBUGP("nf_ct_ras: expect Q.931 ");
NF_CT_DUMP_TUPLE(&exp->tuple);
} else
ret = -1;
nf_conntrack_expect_put(exp);
/* Ignore rasAddress */
return ret;
}
/****************************************************************************/
static int process_irr(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, InfoRequestResponse *irr)
{
int ret;
typeof(set_ras_addr_hook) set_ras_addr;
typeof(set_sig_addr_hook) set_sig_addr;
DEBUGP("nf_ct_ras: IRR\n");
set_ras_addr = rcu_dereference(set_ras_addr_hook);
if (set_ras_addr && ct->status & IPS_NAT_MASK) {
ret = set_ras_addr(pskb, ct, ctinfo, data,
&irr->rasAddress, 1);
if (ret < 0)
return -1;
}
set_sig_addr = rcu_dereference(set_sig_addr_hook);
if (set_sig_addr && ct->status & IPS_NAT_MASK) {
ret = set_sig_addr(pskb, ct, ctinfo, data,
irr->callSignalAddress.item,
irr->callSignalAddress.count);
if (ret < 0)
return -1;
}
return 0;
}
/****************************************************************************/
static int process_ras(struct sk_buff **pskb, struct nf_conn *ct,
enum ip_conntrack_info ctinfo,
unsigned char **data, RasMessage *ras)
{
switch (ras->choice) {
case eRasMessage_gatekeeperRequest:
return process_grq(pskb, ct, ctinfo, data,
&ras->gatekeeperRequest);
case eRasMessage_gatekeeperConfirm:
return process_gcf(pskb, ct, ctinfo, data,
&ras->gatekeeperConfirm);
case eRasMessage_registrationRequest:
return process_rrq(pskb, ct, ctinfo, data,
&ras->registrationRequest);
case eRasMessage_registrationConfirm:
return process_rcf(pskb, ct, ctinfo, data,
&ras->registrationConfirm);
case eRasMessage_unregistrationRequest:
return process_urq(pskb, ct, ctinfo, data,
&ras->unregistrationRequest);
case eRasMessage_admissionRequest:
return process_arq(pskb, ct, ctinfo, data,
&ras->admissionRequest);
case eRasMessage_admissionConfirm:
return process_acf(pskb, ct, ctinfo, data,
&ras->admissionConfirm);
case eRasMessage_locationRequest:
return process_lrq(pskb, ct, ctinfo, data,
&ras->locationRequest);
case eRasMessage_locationConfirm:
return process_lcf(pskb, ct, ctinfo, data,
&ras->locationConfirm);
case eRasMessage_infoRequestResponse:
return process_irr(pskb, ct, ctinfo, data,
&ras->infoRequestResponse);
default:
DEBUGP("nf_ct_ras: RAS message %d\n", ras->choice);
break;
}
return 0;
}
/****************************************************************************/
static int ras_help(struct sk_buff **pskb, unsigned int protoff,
struct nf_conn *ct, enum ip_conntrack_info ctinfo)
{
static RasMessage ras;
unsigned char *data;
int datalen = 0;
int ret;
DEBUGP("nf_ct_ras: skblen = %u\n", (*pskb)->len);
spin_lock_bh(&nf_h323_lock);
/* Get UDP data */
data = get_udp_data(pskb, protoff, &datalen);
if (data == NULL)
goto accept;
DEBUGP("nf_ct_ras: RAS message len=%d ", datalen);
NF_CT_DUMP_TUPLE(&ct->tuplehash[CTINFO2DIR(ctinfo)].tuple);
/* Decode RAS message */
ret = DecodeRasMessage(data, datalen, &ras);
if (ret < 0) {
if (net_ratelimit())
printk("nf_ct_ras: decoding error: %s\n",
ret == H323_ERROR_BOUND ?
"out of bound" : "out of range");
goto accept;
}
/* Process RAS message */
if (process_ras(pskb, ct, ctinfo, &data, &ras) < 0)
goto drop;
accept:
spin_unlock_bh(&nf_h323_lock);
return NF_ACCEPT;
drop:
spin_unlock_bh(&nf_h323_lock);
if (net_ratelimit())
printk("nf_ct_ras: packet dropped\n");
return NF_DROP;
}
/****************************************************************************/
static struct nf_conntrack_helper nf_conntrack_helper_ras[] __read_mostly = {
{
.name = "RAS",
.me = THIS_MODULE,
.max_expected = 32,
.timeout = 240,
.tuple.src.l3num = AF_INET,
.tuple.src.u.udp.port = __constant_htons(RAS_PORT),
.tuple.dst.protonum = IPPROTO_UDP,
.mask.src.l3num = 0xFFFF,
.mask.src.u.udp.port = __constant_htons(0xFFFF),
.mask.dst.protonum = 0xFF,
.help = ras_help,
},
{
.name = "RAS",
.me = THIS_MODULE,
.max_expected = 32,
.timeout = 240,
.tuple.src.l3num = AF_INET6,
.tuple.src.u.udp.port = __constant_htons(RAS_PORT),
.tuple.dst.protonum = IPPROTO_UDP,
.mask.src.l3num = 0xFFFF,
.mask.src.u.udp.port = __constant_htons(0xFFFF),
.mask.dst.protonum = 0xFF,
.help = ras_help,
},
};
/****************************************************************************/
static void __exit nf_conntrack_h323_fini(void)
{
nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[1]);
nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
kfree(h323_buffer);
DEBUGP("nf_ct_h323: fini\n");
}
/****************************************************************************/
static int __init nf_conntrack_h323_init(void)
{
int ret;
h323_buffer = kmalloc(65536, GFP_KERNEL);
if (!h323_buffer)
return -ENOMEM;
ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[0]);
if (ret < 0)
goto err1;
ret = nf_conntrack_helper_register(&nf_conntrack_helper_q931[1]);
if (ret < 0)
goto err2;
ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[0]);
if (ret < 0)
goto err3;
ret = nf_conntrack_helper_register(&nf_conntrack_helper_ras[1]);
if (ret < 0)
goto err4;
DEBUGP("nf_ct_h323: init success\n");
return 0;
err4:
nf_conntrack_helper_unregister(&nf_conntrack_helper_ras[0]);
err3:
nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[1]);
err2:
nf_conntrack_helper_unregister(&nf_conntrack_helper_q931[0]);
err1:
return ret;
}
/****************************************************************************/
module_init(nf_conntrack_h323_init);
module_exit(nf_conntrack_h323_fini);
EXPORT_SYMBOL_GPL(get_h225_addr);
EXPORT_SYMBOL_GPL(set_h245_addr_hook);
EXPORT_SYMBOL_GPL(set_h225_addr_hook);
EXPORT_SYMBOL_GPL(set_sig_addr_hook);
EXPORT_SYMBOL_GPL(set_ras_addr_hook);
EXPORT_SYMBOL_GPL(nat_rtp_rtcp_hook);
EXPORT_SYMBOL_GPL(nat_t120_hook);
EXPORT_SYMBOL_GPL(nat_h245_hook);
EXPORT_SYMBOL_GPL(nat_callforwarding_hook);
EXPORT_SYMBOL_GPL(nat_q931_hook);
MODULE_AUTHOR("Jing Min Zhao <zhaojingmin@users.sourceforge.net>");
MODULE_DESCRIPTION("H.323 connection tracking helper");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ip_conntrack_h323");
......@@ -36,7 +36,8 @@ static field_t _TransportAddress_ipxAddress[] = { /* SEQUENCE */
};
static field_t _TransportAddress_ip6Address[] = { /* SEQUENCE */
{FNAME("ip") OCTSTR, FIXD, 16, 0, SKIP, 0, NULL},
{FNAME("ip") OCTSTR, FIXD, 16, 0, DECODE,
offsetof(TransportAddress_ip6Address, ip6), NULL},
{FNAME("port") INT, WORD, 0, 0, SKIP, 0, NULL},
};
......@@ -65,8 +66,8 @@ static field_t _TransportAddress[] = { /* CHOICE */
_TransportAddress_ipSourceRoute},
{FNAME("ipxAddress") SEQ, 0, 3, 3, SKIP, 0,
_TransportAddress_ipxAddress},
{FNAME("ip6Address") SEQ, 0, 2, 2, SKIP | EXT, 0,
_TransportAddress_ip6Address},
{FNAME("ip6Address") SEQ, 0, 2, 2, DECODE | EXT,
offsetof(TransportAddress, ip6Address), _TransportAddress_ip6Address},
{FNAME("netBios") OCTSTR, FIXD, 16, 0, SKIP, 0, NULL},
{FNAME("nsap") OCTSTR, 5, 1, 0, SKIP, 0, NULL},
{FNAME("nonStandardAddress") SEQ, 0, 2, 2, SKIP, 0,
......
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