linux/net/ipv4/netfilter/nf_nat_h323.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * H.323 extension for NAT alteration.
 *
 * Copyright (c) 2006 Jing Min Zhao <[email protected]>
 * Copyright (c) 2006-2012 Patrick McHardy <[email protected]>
 *
 * Based on the 'brute force' H.323 NAT module by
 * Jozsef Kadlecsik <[email protected]>
 */

#include <linux/module.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_conntrack_helper.h>
#include <net/netfilter/nf_conntrack_expect.h>
#include <linux/netfilter/nf_conntrack_h323.h>

/****************************************************************************/
static int set_addr(struct sk_buff *skb, unsigned int protoff,
		    unsigned char **data, int dataoff,
		    unsigned int addroff, __be32 ip, __be16 port)
{ … }

/****************************************************************************/
static int set_h225_addr(struct sk_buff *skb, unsigned int protoff,
			 unsigned char **data, int dataoff,
			 TransportAddress *taddr,
			 union nf_inet_addr *addr, __be16 port)
{ … }

/****************************************************************************/
static int set_h245_addr(struct sk_buff *skb, unsigned protoff,
			 unsigned char **data, int dataoff,
			 H245_TransportAddress *taddr,
			 union nf_inet_addr *addr, __be16 port)
{ … }

/****************************************************************************/
static int set_sig_addr(struct sk_buff *skb, struct nf_conn *ct,
			enum ip_conntrack_info ctinfo,
			unsigned int protoff, unsigned char **data,
			TransportAddress *taddr, int count)
{ … }

/****************************************************************************/
static int set_ras_addr(struct sk_buff *skb, struct nf_conn *ct,
			enum ip_conntrack_info ctinfo,
			unsigned int protoff, unsigned char **data,
			TransportAddress *taddr, int count)
{ … }

/****************************************************************************/
static int nat_rtp_rtcp(struct sk_buff *skb, struct nf_conn *ct,
			enum ip_conntrack_info ctinfo,
			unsigned int protoff, 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)
{ … }

/****************************************************************************/
static int nat_t120(struct sk_buff *skb, struct nf_conn *ct,
		    enum ip_conntrack_info ctinfo,
		    unsigned int protoff, unsigned char **data, int dataoff,
		    H245_TransportAddress *taddr, __be16 port,
		    struct nf_conntrack_expect *exp)
{ … }

/****************************************************************************/
static int nat_h245(struct sk_buff *skb, struct nf_conn *ct,
		    enum ip_conntrack_info ctinfo,
		    unsigned int protoff, unsigned char **data, int dataoff,
		    TransportAddress *taddr, __be16 port,
		    struct nf_conntrack_expect *exp)
{ … }

/****************************************************************************
 * 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)
{ … }

/****************************************************************************/
static int nat_q931(struct sk_buff *skb, struct nf_conn *ct,
		    enum ip_conntrack_info ctinfo,
		    unsigned int protoff, unsigned char **data,
		    TransportAddress *taddr, int idx,
		    __be16 port, struct nf_conntrack_expect *exp)
{ … }

/****************************************************************************/
static void ip_nat_callforwarding_expect(struct nf_conn *new,
					 struct nf_conntrack_expect *this)
{ … }

/****************************************************************************/
static int nat_callforwarding(struct sk_buff *skb, struct nf_conn *ct,
			      enum ip_conntrack_info ctinfo,
			      unsigned int protoff,
			      unsigned char **data, int dataoff,
			      TransportAddress *taddr, __be16 port,
			      struct nf_conntrack_expect *exp)
{ … }

static struct nf_ct_helper_expectfn q931_nat = …;

static struct nf_ct_helper_expectfn callforwarding_nat = …;

static const struct nfct_h323_nat_hooks nathooks = …;

/****************************************************************************/
static int __init nf_nat_h323_init(void)
{ … }

/****************************************************************************/
static void __exit nf_nat_h323_fini(void)
{ … }

/****************************************************************************/
module_init(…) …;
module_exit(nf_nat_h323_fini);

MODULE_AUTHOR(…) …;
MODULE_DESCRIPTION(…) …;
MODULE_LICENSE(…) …;
MODULE_ALIAS_NF_NAT_HELPER(…) …;