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/*
* RTSP extension for IP connection tracking.
* (C) 2003 by Tom Marshall <tmarshall at real.com>
* based on ip_conntrack_irc.h
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef _IP_CONNTRACK_RTSP_H
#define _IP_CONNTRACK_RTSP_H
//#define IP_NF_RTSP_DEBUG 1
#define IP_NF_RTSP_VERSION "0.6.21"
#ifdef __KERNEL__
/* port block types */
typedef enum {
pb_single, /* client_port=x */
pb_range, /* client_port=x-y */
pb_discon /* client_port=x/y (rtspbis) */
} portblock_t;
/* We record seq number and length of rtsp headers here, all in host order. */
/*
* This structure is per expected connection. It is a member of struct
* ip_conntrack_expect. The TCP SEQ for the conntrack expect is stored
* there and we are expected to only store the length of the data which
* needs replaced. If a packet contains multiple RTSP messages, we create
* one expected connection per message.
*
* We use these variables to mark the entire header block. This may seem
* like overkill, but the nature of RTSP requires it. A header may appear
* multiple times in a message. We must treat two Transport headers the
* same as one Transport header with two entries.
*/
struct ip_ct_rtsp_expect
{
u_int32_t len; /* length of header block */
portblock_t pbtype; /* Type of port block that was requested */
u_int16_t loport; /* Port that was requested, low or first */
u_int16_t hiport; /* Port that was requested, high or second */
#if 0
uint method; /* RTSP method */
uint cseq; /* CSeq from request */
#endif
};
extern unsigned int (*nf_nat_rtsp_hook)(struct sk_buff *skb,
enum ip_conntrack_info ctinfo,
unsigned int matchoff, unsigned int matchlen,
struct ip_ct_rtsp_expect *prtspexp,
struct nf_conntrack_expect *exp);
extern void (*nf_nat_rtsp_hook_expectfn)(struct nf_conn *ct, struct nf_conntrack_expect *exp);
#define RTSP_PORT 554
#endif /* __KERNEL__ */
#endif /* _IP_CONNTRACK_RTSP_H */
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