release/src-rt-6.x.4708/linux/linux-2.6.36/include/linux/netfilter/nf_conntrack_rtsp.h

   1 /*
   2  * RTSP extension for IP connection tracking.
   3  * (C) 2003 by Tom Marshall <tmarshall at real.com>
   4  * based on ip_conntrack_irc.h
   5  *
   6  *      This program is free software; you can redistribute it and/or
   7  *      modify it under the terms of the GNU General Public License
   8  *      as published by the Free Software Foundation; either version
   9  *      2 of the License, or (at your option) any later version.
  10  */
  11 #ifndef _IP_CONNTRACK_RTSP_H
  12 #define _IP_CONNTRACK_RTSP_H
  13
  14 //#define IP_NF_RTSP_DEBUG 1
  15 #define IP_NF_RTSP_VERSION "0.6.21"
  16
  17 #ifdef __KERNEL__
  18 /* port block types */
  19 typedef enum {
  20     pb_single,  /* client_port=x */
  21     pb_range,   /* client_port=x-y */
  22     pb_discon   /* client_port=x/y (rtspbis) */
  23 } portblock_t;
  24
  25 /* We record seq number and length of rtsp headers here, all in host order. */
  26
  27 /*
  28  * This structure is per expected connection.  It is a member of struct
  29  * ip_conntrack_expect.  The TCP SEQ for the conntrack expect is stored
  30  * there and we are expected to only store the length of the data which
  31  * needs replaced.  If a packet contains multiple RTSP messages, we create
  32  * one expected connection per message.
  33  *
  34  * We use these variables to mark the entire header block.  This may seem
  35  * like overkill, but the nature of RTSP requires it.  A header may appear
  36  * multiple times in a message.  We must treat two Transport headers the
  37  * same as one Transport header with two entries.
  38  */
  39 struct ip_ct_rtsp_expect
  40 {
  41     u_int32_t   len;        /* length of header block */
  42     portblock_t pbtype;     /* Type of port block that was requested */
  43     u_int16_t   loport;     /* Port that was requested, low or first */
  44     u_int16_t   hiport;     /* Port that was requested, high or second */
  45 #if 0
  46     uint        method;     /* RTSP method */
  47     uint        cseq;       /* CSeq from request */
  48 #endif
  49 };
  50
  51 extern unsigned int (*nf_nat_rtsp_hook)(struct sk_buff *skb,
  52                                  enum ip_conntrack_info ctinfo,
  53                                  unsigned int matchoff, unsigned int matchlen,
  54                                  struct ip_ct_rtsp_expect *prtspexp,
  55                                  struct nf_conntrack_expect *exp);
  56
  57 extern void (*nf_nat_rtsp_hook_expectfn)(struct nf_conn *ct, struct nf_conntrack_expect *exp);
  58
  59 #define RTSP_PORT   554
  60
  61 #endif /* __KERNEL__ */
  62
  63 #endif /* _IP_CONNTRACK_RTSP_H */