xtables-addons: move to package/, add myself as maintainer

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@35193 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 1334 insertions, 0 deletions

diff --git a/package/network/utils/xtables-addons/patches-1.x/100-add-rtsp-conntrack.patch b/package/network/utils/xtables-addons/patches-1.x/100-add-rtsp-conntrack.patch
new file mode 100644
index 0000000000..34cdc8c17c
--- /dev/null
+++ b/package/network/utils/xtables-addons/patches-1.x/100-add-rtsp-conntrack.patch
@@ -0,0 +1,1334 @@
+--- /dev/null
++++ b/extensions/rtsp/Kbuild
+@@ -0,0 +1,4 @@
++# -*- Makefile -*-
++
++obj-m += nf_nat_rtsp.o
++obj-m += nf_conntrack_rtsp.o
+--- /dev/null
++++ b/extensions/rtsp/netfilter_helpers.h
+@@ -0,0 +1,133 @@
++/*
++ * Helpers for netfiler modules.  This file provides implementations for basic
++ * functions such as strncasecmp(), etc.
++ *
++ * gcc will warn for defined but unused functions, so we only include the
++ * functions requested.  The following macros are used:
++ *   NF_NEED_STRNCASECMP        nf_strncasecmp()
++ *   NF_NEED_STRTOU16           nf_strtou16()
++ *   NF_NEED_STRTOU32           nf_strtou32()
++ */
++#ifndef _NETFILTER_HELPERS_H
++#define _NETFILTER_HELPERS_H
++
++/* Only include these functions for kernel code. */
++#ifdef __KERNEL__
++
++#include <linux/ctype.h>
++#define iseol(c) ( (c) == '\r' || (c) == '\n' )
++
++/*
++ * The standard strncasecmp()
++ */
++#ifdef NF_NEED_STRNCASECMP
++static int
++nf_strncasecmp(const char* s1, const char* s2, u_int32_t len)
++{
++    if (s1 == NULL || s2 == NULL)
++    {
++        if (s1 == NULL && s2 == NULL)
++        {
++            return 0;
++        }
++        return (s1 == NULL) ? -1 : 1;
++    }
++    while (len > 0 && tolower(*s1) == tolower(*s2))
++    {
++        len--;
++        s1++;
++        s2++;
++    }
++    return ( (len == 0) ? 0 : (tolower(*s1) - tolower(*s2)) );
++}
++#endif /* NF_NEED_STRNCASECMP */
++
++/*
++ * Parse a string containing a 16-bit unsigned integer.
++ * Returns the number of chars used, or zero if no number is found.
++ */
++#ifdef NF_NEED_STRTOU16
++static int
++nf_strtou16(const char* pbuf, u_int16_t* pval)
++{
++    int n = 0;
++
++    *pval = 0;
++    while (isdigit(pbuf[n]))
++    {
++        *pval = (*pval * 10) + (pbuf[n] - '0');
++        n++;
++    }
++
++    return n;
++}
++#endif /* NF_NEED_STRTOU16 */
++
++/*
++ * Parse a string containing a 32-bit unsigned integer.
++ * Returns the number of chars used, or zero if no number is found.
++ */
++#ifdef NF_NEED_STRTOU32
++static int
++nf_strtou32(const char* pbuf, u_int32_t* pval)
++{
++    int n = 0;
++
++    *pval = 0;
++    while (pbuf[n] >= '0' && pbuf[n] <= '9')
++    {
++        *pval = (*pval * 10) + (pbuf[n] - '0');
++        n++;
++    }
++
++    return n;
++}
++#endif /* NF_NEED_STRTOU32 */
++
++/*
++ * Given a buffer and length, advance to the next line and mark the current
++ * line.
++ */
++#ifdef NF_NEED_NEXTLINE
++static int
++nf_nextline(char* p, uint len, uint* poff, uint* plineoff, uint* plinelen)
++{
++    uint    off = *poff;
++    uint    physlen = 0;
++
++    if (off >= len)
++    {
++        return 0;
++    }
++
++    while (p[off] != '\n')
++    {
++        if (len-off <= 1)
++        {
++            return 0;
++        }
++
++        physlen++;
++        off++;
++    }
++
++    /* if we saw a crlf, physlen needs adjusted */
++    if (physlen > 0 && p[off] == '\n' && p[off-1] == '\r')
++    {
++        physlen--;
++    }
++
++    /* advance past the newline */
++    off++;
++
++    *plineoff = *poff;
++    *plinelen = physlen;
++    *poff = off;
++
++    return 1;
++}
++#endif /* NF_NEED_NEXTLINE */
++
++#endif /* __KERNEL__ */
++
++#endif /* _NETFILTER_HELPERS_H */
+--- /dev/null
++++ b/extensions/rtsp/netfilter_mime.h
+@@ -0,0 +1,89 @@
++/*
++ * MIME functions for netfilter modules.  This file provides implementations
++ * for basic MIME parsing.  MIME headers are used in many protocols, such as
++ * HTTP, RTSP, SIP, etc.
++ *
++ * gcc will warn for defined but unused functions, so we only include the
++ * functions requested.  The following macros are used:
++ *   NF_NEED_MIME_NEXTLINE      nf_mime_nextline()
++ */
++#ifndef _NETFILTER_MIME_H
++#define _NETFILTER_MIME_H
++
++/* Only include these functions for kernel code. */
++#ifdef __KERNEL__
++
++#include <linux/ctype.h>
++
++/*
++ * Given a buffer and length, advance to the next line and mark the current
++ * line.  If the current line is empty, *plinelen will be set to zero.  If
++ * not, it will be set to the actual line length (including CRLF).
++ *
++ * 'line' in this context means logical line (includes LWS continuations).
++ * Returns 1 on success, 0 on failure.
++ */
++#ifdef NF_NEED_MIME_NEXTLINE
++static int
++nf_mime_nextline(char* p, uint len, uint* poff, uint* plineoff, uint* plinelen)
++{
++    uint    off = *poff;
++    uint    physlen = 0;
++    int     is_first_line = 1;
++
++    if (off >= len)
++    {
++        return 0;
++    }
++
++    do
++    {
++        while (p[off] != '\n')
++        {
++            if (len-off <= 1)
++            {
++                return 0;
++            }
++
++            physlen++;
++            off++;
++        }
++
++        /* if we saw a crlf, physlen needs adjusted */
++        if (physlen > 0 && p[off] == '\n' && p[off-1] == '\r')
++        {
++            physlen--;
++        }
++
++        /* advance past the newline */
++        off++;
++
++        /* check for an empty line */
++        if (physlen == 0)
++        {
++            break;
++        }
++
++        /* check for colon on the first physical line */
++        if (is_first_line)
++        {
++            is_first_line = 0;
++            if (memchr(p+(*poff), ':', physlen) == NULL)
++            {
++                return 0;
++            }
++        }
++    }
++    while (p[off] == ' ' || p[off] == '\t');
++
++    *plineoff = *poff;
++    *plinelen = (physlen == 0) ? 0 : (off - *poff);
++    *poff = off;
++
++    return 1;
++}
++#endif /* NF_NEED_MIME_NEXTLINE */
++
++#endif /* __KERNEL__ */
++
++#endif /* _NETFILTER_MIME_H */
+--- /dev/null
++++ b/extensions/rtsp/nf_conntrack_rtsp.c
+@@ -0,0 +1,519 @@
++/*
++ * RTSP extension for IP connection tracking
++ * (C) 2003 by Tom Marshall <tmarshall at real.com>
++ * based on ip_conntrack_irc.c
++ *
++ *      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.
++ *
++ * Module load syntax:
++ *   insmod nf_conntrack_rtsp.o ports=port1,port2,...port<MAX_PORTS>
++ *                              max_outstanding=n setup_timeout=secs
++ *
++ * If no ports are specified, the default will be port 554.
++ *
++ * With max_outstanding you can define the maximum number of not yet
++ * answered SETUP requests per RTSP session (default 8).
++ * With setup_timeout you can specify how long the system waits for
++ * an expected data channel (default 300 seconds).
++ *
++ * 2005-02-13: Harald Welte <laforge at netfilter.org>
++ * 	- port to 2.6
++ * 	- update to recent post-2.6.11 api changes
++ * 2006-09-14: Steven Van Acker <deepstar at singularity.be>
++ *      - removed calls to NAT code from conntrack helper: NAT no longer needed to use rtsp-conntrack
++ * 2007-04-18: Michael Guntsche <mike at it-loops.com>
++ * 			- Port to new NF API
++ */
++
++#include <linux/module.h>
++#include <linux/netfilter.h>
++#include <linux/ip.h>
++#include <linux/inet.h>
++#include <net/tcp.h>
++
++#include <net/netfilter/nf_conntrack.h>
++#include <net/netfilter/nf_conntrack_expect.h>
++#include <net/netfilter/nf_conntrack_helper.h>
++#include "nf_conntrack_rtsp.h"
++
++#define NF_NEED_STRNCASECMP
++#define NF_NEED_STRTOU16
++#define NF_NEED_STRTOU32
++#define NF_NEED_NEXTLINE
++#include "netfilter_helpers.h"
++#define NF_NEED_MIME_NEXTLINE
++#include "netfilter_mime.h"
++
++#include <linux/ctype.h>
++#define MAX_SIMUL_SETUP 8 /* XXX: use max_outstanding */
++
++#define MAX_PORTS 8
++static int ports[MAX_PORTS];
++static int num_ports = 0;
++static int max_outstanding = 8;
++static unsigned int setup_timeout = 300;
++
++MODULE_AUTHOR("Tom Marshall <tmarshall at real.com>");
++MODULE_DESCRIPTION("RTSP connection tracking module");
++MODULE_LICENSE("GPL");
++module_param_array(ports, int, &num_ports, 0400);
++MODULE_PARM_DESC(ports, "port numbers of RTSP servers");
++module_param(max_outstanding, int, 0400);
++MODULE_PARM_DESC(max_outstanding, "max number of outstanding SETUP requests per RTSP session");
++module_param(setup_timeout, int, 0400);
++MODULE_PARM_DESC(setup_timeout, "timeout on for unestablished data channels");
++
++static char *rtsp_buffer;
++static DEFINE_SPINLOCK(rtsp_buffer_lock);
++
++static struct nf_conntrack_expect_policy rtsp_exp_policy; 
++
++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);
++void (*nf_nat_rtsp_hook_expectfn)(struct nf_conn *ct, struct nf_conntrack_expect *exp);
++
++EXPORT_SYMBOL_GPL(nf_nat_rtsp_hook);
++
++/*
++ * Max mappings we will allow for one RTSP connection (for RTP, the number
++ * of allocated ports is twice this value).  Note that SMIL burns a lot of
++ * ports so keep this reasonably high.  If this is too low, you will see a
++ * lot of "no free client map entries" messages.
++ */
++#define MAX_PORT_MAPS 16
++
++/*** default port list was here in the masq code: 554, 3030, 4040 ***/
++
++#define SKIP_WSPACE(ptr,len,off) while(off < len && isspace(*(ptr+off))) { off++; }
++
++/*
++ * Parse an RTSP packet.
++ *
++ * Returns zero if parsing failed.
++ *
++ * Parameters:
++ *  IN      ptcp        tcp data pointer
++ *  IN      tcplen      tcp data len
++ *  IN/OUT  ptcpoff     points to current tcp offset
++ *  OUT     phdrsoff    set to offset of rtsp headers
++ *  OUT     phdrslen    set to length of rtsp headers
++ *  OUT     pcseqoff    set to offset of CSeq header
++ *  OUT     pcseqlen    set to length of CSeq header
++ */
++static int
++rtsp_parse_message(char* ptcp, uint tcplen, uint* ptcpoff,
++                   uint* phdrsoff, uint* phdrslen,
++                   uint* pcseqoff, uint* pcseqlen,
++                   uint* transoff, uint* translen)
++{
++	uint    entitylen = 0;
++	uint    lineoff;
++	uint    linelen;
++	
++	if (!nf_nextline(ptcp, tcplen, ptcpoff, &lineoff, &linelen))
++		return 0;
++	
++	*phdrsoff = *ptcpoff;
++	while (nf_mime_nextline(ptcp, tcplen, ptcpoff, &lineoff, &linelen)) {
++		if (linelen == 0) {
++			if (entitylen > 0)
++				*ptcpoff += min(entitylen, tcplen - *ptcpoff);
++			break;
++		}
++		if (lineoff+linelen > tcplen) {
++			pr_info("!! overrun !!\n");
++			break;
++		}
++		
++		if (nf_strncasecmp(ptcp+lineoff, "CSeq:", 5) == 0) {
++			*pcseqoff = lineoff;
++			*pcseqlen = linelen;
++		} 
++
++		if (nf_strncasecmp(ptcp+lineoff, "Transport:", 10) == 0) {
++			*transoff = lineoff;
++			*translen = linelen;
++		}
++		
++		if (nf_strncasecmp(ptcp+lineoff, "Content-Length:", 15) == 0) {
++			uint off = lineoff+15;
++			SKIP_WSPACE(ptcp+lineoff, linelen, off);
++			nf_strtou32(ptcp+off, &entitylen);
++		}
++	}
++	*phdrslen = (*ptcpoff) - (*phdrsoff);
++	
++	return 1;
++}
++
++/*
++ * Find lo/hi client ports (if any) in transport header
++ * In:
++ *   ptcp, tcplen = packet
++ *   tranoff, tranlen = buffer to search
++ *
++ * Out:
++ *   pport_lo, pport_hi = lo/hi ports (host endian)
++ *
++ * Returns nonzero if any client ports found
++ *
++ * Note: it is valid (and expected) for the client to request multiple
++ * transports, so we need to parse the entire line.
++ */
++static int
++rtsp_parse_transport(char* ptran, uint tranlen,
++                     struct ip_ct_rtsp_expect* prtspexp)
++{
++	int     rc = 0;
++	uint    off = 0;
++	
++	if (tranlen < 10 || !iseol(ptran[tranlen-1]) ||
++	    nf_strncasecmp(ptran, "Transport:", 10) != 0) {
++		pr_info("sanity check failed\n");
++		return 0;
++	}
++	
++	pr_debug("tran='%.*s'\n", (int)tranlen, ptran);
++	off += 10;
++	SKIP_WSPACE(ptran, tranlen, off);
++	
++	/* Transport: tran;field;field=val,tran;field;field=val,... */
++	while (off < tranlen) {
++		const char* pparamend;
++		uint        nextparamoff;
++		
++		pparamend = memchr(ptran+off, ',', tranlen-off);
++		pparamend = (pparamend == NULL) ? ptran+tranlen : pparamend+1;
++		nextparamoff = pparamend-ptran;
++		
++		while (off < nextparamoff) {
++			const char* pfieldend;
++			uint        nextfieldoff;
++			
++			pfieldend = memchr(ptran+off, ';', nextparamoff-off);
++			nextfieldoff = (pfieldend == NULL) ? nextparamoff : pfieldend-ptran+1;
++		   
++			if (strncmp(ptran+off, "client_port=", 12) == 0) {
++				u_int16_t   port;
++				uint        numlen;
++		    
++				off += 12;
++				numlen = nf_strtou16(ptran+off, &port);
++				off += numlen;
++				if (prtspexp->loport != 0 && prtspexp->loport != port)
++					pr_debug("multiple ports found, port %hu ignored\n", port);
++				else {
++					pr_debug("lo port found : %hu\n", port);
++					prtspexp->loport = prtspexp->hiport = port;
++					if (ptran[off] == '-') {
++						off++;
++						numlen = nf_strtou16(ptran+off, &port);
++						off += numlen;
++						prtspexp->pbtype = pb_range;
++						prtspexp->hiport = port;
++						
++						// If we have a range, assume rtp:
++						// loport must be even, hiport must be loport+1
++						if ((prtspexp->loport & 0x0001) != 0 ||
++						    prtspexp->hiport != prtspexp->loport+1) {
++							pr_debug("incorrect range: %hu-%hu, correcting\n",
++							       prtspexp->loport, prtspexp->hiport);
++							prtspexp->loport &= 0xfffe;
++							prtspexp->hiport = prtspexp->loport+1;
++						}
++					} else if (ptran[off] == '/') {
++						off++;
++						numlen = nf_strtou16(ptran+off, &port);
++						off += numlen;
++						prtspexp->pbtype = pb_discon;
++						prtspexp->hiport = port;
++					}
++					rc = 1;
++				}
++			}
++			
++			/*
++			 * Note we don't look for the destination parameter here.
++			 * If we are using NAT, the NAT module will handle it.  If not,
++			 * and the client is sending packets elsewhere, the expectation
++			 * will quietly time out.
++			 */
++			
++			off = nextfieldoff;
++		}
++		
++		off = nextparamoff;
++	}
++	
++	return rc;
++}
++
++void expected(struct nf_conn *ct, struct nf_conntrack_expect *exp)
++{
++		typeof(nf_nat_rtsp_hook_expectfn) nf_nat_rtsp_expectfn;
++		nf_nat_rtsp_expectfn = rcu_dereference(nf_nat_rtsp_hook_expectfn);
++    if(nf_nat_rtsp_expectfn && ct->master->status & IPS_NAT_MASK) {
++        nf_nat_rtsp_expectfn(ct,exp);
++    }
++}
++
++/*** conntrack functions ***/
++
++/* outbound packet: client->server */
++
++static inline int
++help_out(struct sk_buff *skb, unsigned char *rb_ptr, unsigned int datalen,
++                struct nf_conn *ct, enum ip_conntrack_info ctinfo)
++{
++	struct ip_ct_rtsp_expect expinfo;
++	
++	int dir = CTINFO2DIR(ctinfo);   /* = IP_CT_DIR_ORIGINAL */
++	//struct  tcphdr* tcph = (void*)iph + iph->ihl * 4;
++	//uint    tcplen = pktlen - iph->ihl * 4;
++	char*   pdata = rb_ptr;
++	//uint    datalen = tcplen - tcph->doff * 4;
++	uint    dataoff = 0;
++	int ret = NF_ACCEPT;
++	
++	struct nf_conntrack_expect *exp;
++	
++	__be16 be_loport;
++	
++	typeof(nf_nat_rtsp_hook) nf_nat_rtsp;
++
++	memset(&expinfo, 0, sizeof(expinfo));
++	
++	while (dataoff < datalen) {
++		uint    cmdoff = dataoff;
++		uint    hdrsoff = 0;
++		uint    hdrslen = 0;
++		uint    cseqoff = 0;
++		uint    cseqlen = 0;
++		uint    transoff = 0;
++		uint    translen = 0;
++		uint    off;
++		
++		if (!rtsp_parse_message(pdata, datalen, &dataoff,
++					&hdrsoff, &hdrslen,
++					&cseqoff, &cseqlen,
++					&transoff, &translen))
++			break;      /* not a valid message */
++		
++		if (strncmp(pdata+cmdoff, "SETUP ", 6) != 0)
++			continue;   /* not a SETUP message */
++		pr_debug("found a setup message\n");
++
++		off = 0;
++		if(translen) {
++			rtsp_parse_transport(pdata+transoff, translen, &expinfo);
++		}
++
++		if (expinfo.loport == 0) {
++			pr_debug("no udp transports found\n");
++			continue;   /* no udp transports found */
++		}
++
++		pr_debug("udp transport found, ports=(%d,%hu,%hu)\n",
++		       (int)expinfo.pbtype, expinfo.loport, expinfo.hiport);
++
++		exp = nf_ct_expect_alloc(ct);
++		if (!exp) {
++			ret = NF_DROP;
++			goto out;
++		}
++
++		be_loport = htons(expinfo.loport);
++
++		nf_ct_expect_init(exp, NF_CT_EXPECT_CLASS_DEFAULT, nf_ct_l3num(ct),
++			&ct->tuplehash[!dir].tuple.src.u3, &ct->tuplehash[!dir].tuple.dst.u3,
++			IPPROTO_UDP, NULL, &be_loport); 
++
++		exp->master = ct;
++
++		exp->expectfn = expected;
++		exp->flags = 0;
++
++		if (expinfo.pbtype == pb_range) {
++			pr_debug("Changing expectation mask to handle multiple ports\n");
++			//exp->mask.dst.u.udp.port  = 0xfffe;
++		}
++
++		pr_debug("expect_related %pI4:%u-%pI4:%u\n",
++		       &exp->tuple.src.u3.ip,
++		       ntohs(exp->tuple.src.u.udp.port),
++		       &exp->tuple.dst.u3.ip,
++		       ntohs(exp->tuple.dst.u.udp.port));
++
++		nf_nat_rtsp = rcu_dereference(nf_nat_rtsp_hook);
++		if (nf_nat_rtsp && ct->status & IPS_NAT_MASK)
++			/* pass the request off to the nat helper */
++			ret = nf_nat_rtsp(skb, ctinfo, hdrsoff, hdrslen, &expinfo, exp);
++		else if (nf_ct_expect_related(exp) != 0) {
++			pr_info("nf_conntrack_expect_related failed\n");
++			ret  = NF_DROP;
++		}
++		nf_ct_expect_put(exp);
++		goto out;
++	}
++out:
++
++	return ret;
++}
++
++
++static inline int
++help_in(struct sk_buff *skb, size_t pktlen,
++ struct nf_conn* ct, enum ip_conntrack_info ctinfo)
++{
++ return NF_ACCEPT;
++}
++
++static int help(struct sk_buff *skb, unsigned int protoff,
++		struct nf_conn *ct, enum ip_conntrack_info ctinfo) 
++{
++	struct tcphdr _tcph, *th;
++	unsigned int dataoff, datalen;
++	char *rb_ptr;
++	int ret = NF_DROP;
++
++	/* 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) {
++		pr_debug("conntrackinfo = %u\n", ctinfo);
++		return NF_ACCEPT;
++	} 
++
++	/* Not whole TCP header? */
++	th = skb_header_pointer(skb,protoff, sizeof(_tcph), &_tcph);
++
++	if (!th)
++		return NF_ACCEPT;
++   
++	/* No data ? */
++	dataoff = protoff + th->doff*4;
++	datalen = skb->len - dataoff;
++	if (dataoff >= skb->len)
++		return NF_ACCEPT;
++
++	spin_lock_bh(&rtsp_buffer_lock);
++	rb_ptr = skb_header_pointer(skb, dataoff,
++				    skb->len - dataoff, rtsp_buffer);
++	BUG_ON(rb_ptr == NULL);
++
++#if 0
++	/* Checksum invalid?  Ignore. */
++	/* FIXME: Source route IP option packets --RR */
++	if (tcp_v4_check(tcph, tcplen, iph->saddr, iph->daddr,
++			 csum_partial((char*)tcph, tcplen, 0)))
++	{
++		DEBUGP("bad csum: %p %u %u.%u.%u.%u %u.%u.%u.%u\n",
++		       tcph, tcplen, NIPQUAD(iph->saddr), NIPQUAD(iph->daddr));
++		return NF_ACCEPT;
++	}
++#endif
++
++	switch (CTINFO2DIR(ctinfo)) {
++	case IP_CT_DIR_ORIGINAL:
++		ret = help_out(skb, rb_ptr, datalen, ct, ctinfo);
++		break;
++	case IP_CT_DIR_REPLY:
++		pr_debug("IP_CT_DIR_REPLY\n");
++		/* inbound packet: server->client */
++		ret = NF_ACCEPT;
++		break;
++	}
++
++	spin_unlock_bh(&rtsp_buffer_lock);
++
++	return ret;
++}
++
++static struct nf_conntrack_helper rtsp_helpers[MAX_PORTS];
++static char rtsp_names[MAX_PORTS][10];
++
++/* This function is intentionally _NOT_ defined as __exit */
++static void
++fini(void)
++{
++	int i;
++	for (i = 0; i < num_ports; i++) {
++		pr_debug("unregistering port %d\n", ports[i]);
++		nf_conntrack_helper_unregister(&rtsp_helpers[i]);
++	}
++	kfree(rtsp_buffer);
++}
++
++static int __init
++init(void)
++{
++	int i, ret;
++	struct nf_conntrack_helper *hlpr;
++	char *tmpname;
++
++	printk("nf_conntrack_rtsp v" IP_NF_RTSP_VERSION " loading\n");
++
++	if (max_outstanding < 1) {
++		printk("nf_conntrack_rtsp: max_outstanding must be a positive integer\n");
++		return -EBUSY;
++	}
++	if (setup_timeout < 0) {
++		printk("nf_conntrack_rtsp: setup_timeout must be a positive integer\n");
++		return -EBUSY;
++	}
++
++  rtsp_exp_policy.max_expected = max_outstanding;
++  rtsp_exp_policy.timeout = setup_timeout;
++	
++	rtsp_buffer = kmalloc(65536, GFP_KERNEL);
++	if (!rtsp_buffer) 
++		return -ENOMEM;
++
++	/* If no port given, default to standard rtsp port */
++	if (ports[0] == 0) {
++		ports[0] = RTSP_PORT;
++	}
++
++	for (i = 0; (i < MAX_PORTS) && ports[i]; i++) {
++		hlpr = &rtsp_helpers[i];
++		memset(hlpr, 0, sizeof(struct nf_conntrack_helper));
++		hlpr->tuple.src.l3num = AF_INET;
++		hlpr->tuple.src.u.tcp.port = htons(ports[i]);
++		hlpr->tuple.dst.protonum = IPPROTO_TCP;
++		//hlpr->mask.src.u.tcp.port = 0xFFFF;
++		//hlpr->mask.dst.protonum = 0xFF;
++		hlpr->expect_policy = &rtsp_exp_policy;
++		hlpr->me = THIS_MODULE;
++		hlpr->help = help;
++
++		tmpname = &rtsp_names[i][0];
++		if (ports[i] == RTSP_PORT) {
++			sprintf(tmpname, "rtsp");
++		} else {
++			sprintf(tmpname, "rtsp-%d", i);
++		}
++		hlpr->name = tmpname;
++
++		pr_debug("port #%d: %d\n", i, ports[i]);
++
++		ret = nf_conntrack_helper_register(hlpr);
++
++		if (ret) {
++			printk("nf_conntrack_rtsp: ERROR registering port %d\n", ports[i]);
++			fini();
++			return -EBUSY;
++		}
++		num_ports++;
++	}
++	return 0;
++}
++
++module_init(init);
++module_exit(fini);
++
++EXPORT_SYMBOL(nf_nat_rtsp_hook_expectfn);
++
+--- /dev/null
++++ b/extensions/rtsp/nf_conntrack_rtsp.h
+@@ -0,0 +1,63 @@
++/*
++ * 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 */
+--- /dev/null
++++ b/extensions/rtsp/nf_nat_rtsp.c
+@@ -0,0 +1,491 @@
++/*
++ * RTSP extension for TCP NAT alteration
++ * (C) 2003 by Tom Marshall <tmarshall at real.com>
++ * based on ip_nat_irc.c
++ *
++ *      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.
++ *
++ * Module load syntax:
++ *      insmod nf_nat_rtsp.o ports=port1,port2,...port<MAX_PORTS>
++ *                           stunaddr=<address>
++ *                           destaction=[auto|strip|none]
++ *
++ * If no ports are specified, the default will be port 554 only.
++ *
++ * stunaddr specifies the address used to detect that a client is using STUN.
++ * If this address is seen in the destination parameter, it is assumed that
++ * the client has already punched a UDP hole in the firewall, so we don't
++ * mangle the client_port.  If none is specified, it is autodetected.  It
++ * only needs to be set if you have multiple levels of NAT.  It should be
++ * set to the external address that the STUN clients detect.  Note that in
++ * this case, it will not be possible for clients to use UDP with servers
++ * between the NATs.
++ *
++ * If no destaction is specified, auto is used.
++ *   destaction=auto:  strip destination parameter if it is not stunaddr.
++ *   destaction=strip: always strip destination parameter (not recommended).
++ *   destaction=none:  do not touch destination parameter (not recommended).
++ */
++
++#include <linux/module.h>
++#include <net/tcp.h>
++#include <net/netfilter/nf_nat_helper.h>
++#include <net/netfilter/nf_nat_rule.h>
++#include "nf_conntrack_rtsp.h"
++#include <net/netfilter/nf_conntrack_expect.h>
++
++#include <linux/inet.h>
++#include <linux/ctype.h>
++#define NF_NEED_STRNCASECMP
++#define NF_NEED_STRTOU16
++#include "netfilter_helpers.h"
++#define NF_NEED_MIME_NEXTLINE
++#include "netfilter_mime.h"
++
++#include "../compat_xtables.h"
++
++#define MAX_PORTS       8
++#define DSTACT_AUTO     0
++#define DSTACT_STRIP    1
++#define DSTACT_NONE     2
++
++static char*    stunaddr = NULL;
++static char*    destaction = NULL;
++
++static u_int32_t extip = 0;
++static int       dstact = 0;
++
++MODULE_AUTHOR("Tom Marshall <tmarshall at real.com>");
++MODULE_DESCRIPTION("RTSP network address translation module");
++MODULE_LICENSE("GPL");
++module_param(stunaddr, charp, 0644);
++MODULE_PARM_DESC(stunaddr, "Address for detecting STUN");
++module_param(destaction, charp, 0644);
++MODULE_PARM_DESC(destaction, "Action for destination parameter (auto/strip/none)");
++
++#define SKIP_WSPACE(ptr,len,off) while(off < len && isspace(*(ptr+off))) { off++; }
++
++/*** helper functions ***/
++
++static void
++get_skb_tcpdata(struct sk_buff* skb, char** pptcpdata, uint* ptcpdatalen)
++{
++    struct iphdr*   iph  = ip_hdr(skb);
++    struct tcphdr*  tcph = (void *)iph + ip_hdrlen(skb);
++
++    *pptcpdata = (char*)tcph +  tcph->doff*4;
++    *ptcpdatalen = ((char*)skb_transport_header(skb) + skb->len) - *pptcpdata;
++}
++
++/*** nat functions ***/
++
++/*
++ * Mangle the "Transport:" header:
++ *   - Replace all occurences of "client_port=<spec>"
++ *   - Handle destination parameter
++ *
++ * In:
++ *   ct, ctinfo = conntrack context
++ *   skb        = packet
++ *   tranoff    = Transport header offset from TCP data
++ *   tranlen    = Transport header length (incl. CRLF)
++ *   rport_lo   = replacement low  port (host endian)
++ *   rport_hi   = replacement high port (host endian)
++ *
++ * Returns packet size difference.
++ *
++ * Assumes that a complete transport header is present, ending with CR or LF
++ */
++static int
++rtsp_mangle_tran(enum ip_conntrack_info ctinfo,
++                 struct nf_conntrack_expect* exp,
++								 struct ip_ct_rtsp_expect* prtspexp,
++                 struct sk_buff* skb, uint tranoff, uint tranlen)
++{
++    char*       ptcp;
++    uint        tcplen;
++    char*       ptran;
++    char        rbuf1[16];      /* Replacement buffer (one port) */
++    uint        rbuf1len;       /* Replacement len (one port) */
++    char        rbufa[16];      /* Replacement buffer (all ports) */
++    uint        rbufalen;       /* Replacement len (all ports) */
++    u_int32_t   newip;
++    u_int16_t   loport, hiport;
++    uint        off = 0;
++    uint        diff;           /* Number of bytes we removed */
++
++    struct nf_conn *ct = exp->master;
++    struct nf_conntrack_tuple *t;
++
++    char    szextaddr[15+1];
++    uint    extaddrlen;
++    int     is_stun;
++
++    get_skb_tcpdata(skb, &ptcp, &tcplen);
++    ptran = ptcp+tranoff;
++
++    if (tranoff+tranlen > tcplen || tcplen-tranoff < tranlen ||
++        tranlen < 10 || !iseol(ptran[tranlen-1]) ||
++        nf_strncasecmp(ptran, "Transport:", 10) != 0)
++    {
++        pr_info("sanity check failed\n");
++        return 0;
++    }
++    off += 10;
++    SKIP_WSPACE(ptcp+tranoff, tranlen, off);
++
++    newip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u3.ip;
++    t = &exp->tuple;
++    t->dst.u3.ip = newip;
++
++    extaddrlen = extip ? sprintf(szextaddr, "%pI4", &extip)
++                       : sprintf(szextaddr, "%pI4", &newip);
++    pr_debug("stunaddr=%s (%s)\n", szextaddr, (extip?"forced":"auto"));
++
++    rbuf1len = rbufalen = 0;
++    switch (prtspexp->pbtype)
++    {
++    case pb_single:
++        for (loport = prtspexp->loport; loport != 0; loport++) /* XXX: improper wrap? */
++        {
++            t->dst.u.udp.port = htons(loport);
++            if (nf_ct_expect_related(exp) == 0)
++            {
++                pr_debug("using port %hu\n", loport);
++                break;
++            }
++        }
++        if (loport != 0)
++        {
++            rbuf1len = sprintf(rbuf1, "%hu", loport);
++            rbufalen = sprintf(rbufa, "%hu", loport);
++        }
++        break;
++    case pb_range:
++        for (loport = prtspexp->loport; loport != 0; loport += 2) /* XXX: improper wrap? */
++        {
++            t->dst.u.udp.port = htons(loport);
++            if (nf_ct_expect_related(exp) == 0)
++            {
++                hiport = loport + 1; //~exp->mask.dst.u.udp.port;
++                pr_debug("using ports %hu-%hu\n", loport, hiport);
++                break;
++            }
++        }
++        if (loport != 0)
++        {
++            rbuf1len = sprintf(rbuf1, "%hu", loport);
++            rbufalen = sprintf(rbufa, "%hu-%hu", loport, loport+1);
++        }
++        break;
++    case pb_discon:
++        for (loport = prtspexp->loport; loport != 0; loport++) /* XXX: improper wrap? */
++        {
++            t->dst.u.udp.port = htons(loport);
++            if (nf_ct_expect_related(exp) == 0)
++            {
++                pr_debug("using port %hu (1 of 2)\n", loport);
++                break;
++            }
++        }
++        for (hiport = prtspexp->hiport; hiport != 0; hiport++) /* XXX: improper wrap? */
++        {
++            t->dst.u.udp.port = htons(hiport);
++            if (nf_ct_expect_related(exp) == 0)
++            {
++                pr_debug("using port %hu (2 of 2)\n", hiport);
++                break;
++            }
++        }
++        if (loport != 0 && hiport != 0)
++        {
++            rbuf1len = sprintf(rbuf1, "%hu", loport);
++            if (hiport == loport+1)
++            {
++                rbufalen = sprintf(rbufa, "%hu-%hu", loport, hiport);
++            }
++            else
++            {
++                rbufalen = sprintf(rbufa, "%hu/%hu", loport, hiport);
++            }
++        }
++        break;
++    }
++
++    if (rbuf1len == 0)
++    {
++        return 0;   /* cannot get replacement port(s) */
++    }
++
++    /* Transport: tran;field;field=val,tran;field;field=val,... */
++    while (off < tranlen)
++    {
++        uint        saveoff;
++        const char* pparamend;
++        uint        nextparamoff;
++
++        pparamend = memchr(ptran+off, ',', tranlen-off);
++        pparamend = (pparamend == NULL) ? ptran+tranlen : pparamend+1;
++        nextparamoff = pparamend-ptcp;
++
++        /*
++         * We pass over each param twice.  On the first pass, we look for a
++         * destination= field.  It is handled by the security policy.  If it
++         * is present, allowed, and equal to our external address, we assume
++         * that STUN is being used and we leave the client_port= field alone.
++         */
++        is_stun = 0;
++        saveoff = off;
++        while (off < nextparamoff)
++        {
++            const char* pfieldend;
++            uint        nextfieldoff;
++
++            pfieldend = memchr(ptran+off, ';', nextparamoff-off);
++            nextfieldoff = (pfieldend == NULL) ? nextparamoff : pfieldend-ptran+1;
++
++            if (dstact != DSTACT_NONE && strncmp(ptran+off, "destination=", 12) == 0)
++            {
++                if (strncmp(ptran+off+12, szextaddr, extaddrlen) == 0)
++                {
++                    is_stun = 1;
++                }
++                if (dstact == DSTACT_STRIP || (dstact == DSTACT_AUTO && !is_stun))
++                {
++                    diff = nextfieldoff-off;
++                    if (!nf_nat_mangle_tcp_packet(skb, ct, ctinfo,
++                                                         off, diff, NULL, 0))
++                    {
++                        /* mangle failed, all we can do is bail */
++			nf_ct_unexpect_related(exp);
++                        return 0;
++                    }
++                    get_skb_tcpdata(skb, &ptcp, &tcplen);
++                    ptran = ptcp+tranoff;
++                    tranlen -= diff;
++                    nextparamoff -= diff;
++                    nextfieldoff -= diff;
++                }
++            }
++
++            off = nextfieldoff;
++        }
++        if (is_stun)
++        {
++            continue;
++        }
++        off = saveoff;
++        while (off < nextparamoff)
++        {
++            const char* pfieldend;
++            uint        nextfieldoff;
++
++            pfieldend = memchr(ptran+off, ';', nextparamoff-off);
++            nextfieldoff = (pfieldend == NULL) ? nextparamoff : pfieldend-ptran+1;
++
++            if (strncmp(ptran+off, "client_port=", 12) == 0)
++            {
++                u_int16_t   port;
++                uint        numlen;
++                uint        origoff;
++                uint        origlen;
++                char*       rbuf    = rbuf1;
++                uint        rbuflen = rbuf1len;
++
++                off += 12;
++                origoff = (ptran-ptcp)+off;
++                origlen = 0;
++                numlen = nf_strtou16(ptran+off, &port);
++                off += numlen;
++                origlen += numlen;
++                if (port != prtspexp->loport)
++                {
++                    pr_debug("multiple ports found, port %hu ignored\n", port);
++                }
++                else
++                {
++                    if (ptran[off] == '-' || ptran[off] == '/')
++                    {
++                        off++;
++                        origlen++;
++                        numlen = nf_strtou16(ptran+off, &port);
++                        off += numlen;
++                        origlen += numlen;
++                        rbuf = rbufa;
++                        rbuflen = rbufalen;
++                    }
++
++                    /*
++                     * note we cannot just memcpy() if the sizes are the same.
++                     * the mangle function does skb resizing, checks for a
++                     * cloned skb, and updates the checksums.
++                     *
++                     * parameter 4 below is offset from start of tcp data.
++                     */
++                    diff = origlen-rbuflen;
++                    if (!nf_nat_mangle_tcp_packet(skb, ct, ctinfo,
++                                              origoff, origlen, rbuf, rbuflen))
++                    {
++                        /* mangle failed, all we can do is bail */
++			nf_ct_unexpect_related(exp);
++                        return 0;
++                    }
++                    get_skb_tcpdata(skb, &ptcp, &tcplen);
++                    ptran = ptcp+tranoff;
++                    tranlen -= diff;
++                    nextparamoff -= diff;
++                    nextfieldoff -= diff;
++                }
++            }
++
++            off = nextfieldoff;
++        }
++
++        off = nextparamoff;
++    }
++
++    return 1;
++}
++
++static uint
++help_out(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)
++{
++    char*   ptcp;
++    uint    tcplen;
++    uint    hdrsoff;
++    uint    hdrslen;
++    uint    lineoff;
++    uint    linelen;
++    uint    off;
++
++    //struct iphdr* iph = (struct iphdr*)(*pskb)->nh.iph;
++    //struct tcphdr* tcph = (struct tcphdr*)((void*)iph + iph->ihl*4);
++
++    get_skb_tcpdata(skb, &ptcp, &tcplen);
++    hdrsoff = matchoff;//exp->seq - ntohl(tcph->seq);
++    hdrslen = matchlen;
++    off = hdrsoff;
++    pr_debug("NAT rtsp help_out\n");
++
++    while (nf_mime_nextline(ptcp, hdrsoff+hdrslen, &off, &lineoff, &linelen))
++    {
++        if (linelen == 0)
++        {
++            break;
++        }
++        if (off > hdrsoff+hdrslen)
++        {
++            pr_info("!! overrun !!");
++            break;
++        }
++        pr_debug("hdr: len=%u, %.*s", linelen, (int)linelen, ptcp+lineoff);
++
++        if (nf_strncasecmp(ptcp+lineoff, "Transport:", 10) == 0)
++        {
++            uint oldtcplen = tcplen;
++	    pr_debug("hdr: Transport\n");
++            if (!rtsp_mangle_tran(ctinfo, exp, prtspexp, skb, lineoff, linelen))
++            {
++		pr_debug("hdr: Transport mangle failed");
++                break;
++            }
++            get_skb_tcpdata(skb, &ptcp, &tcplen);
++            hdrslen -= (oldtcplen-tcplen);
++            off -= (oldtcplen-tcplen);
++            lineoff -= (oldtcplen-tcplen);
++            linelen -= (oldtcplen-tcplen);
++            pr_debug("rep: len=%u, %.*s", linelen, (int)linelen, ptcp+lineoff);
++        }
++    }
++
++    return NF_ACCEPT;
++}
++
++static unsigned int
++help(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)
++{
++    int dir = CTINFO2DIR(ctinfo);
++    int rc = NF_ACCEPT;
++
++    switch (dir)
++    {
++    case IP_CT_DIR_ORIGINAL:
++        rc = help_out(skb, ctinfo, matchoff, matchlen, prtspexp, exp);
++        break;
++    case IP_CT_DIR_REPLY:
++	pr_debug("unmangle ! %u\n", ctinfo);
++    	/* XXX: unmangle */
++	rc = NF_ACCEPT;
++        break;
++    }
++    //UNLOCK_BH(&ip_rtsp_lock);
++
++    return rc;
++}
++
++static void expected(struct nf_conn* ct, struct nf_conntrack_expect *exp)
++{
++    struct nf_nat_ipv4_multi_range_compat mr;
++    u_int32_t newdstip, newsrcip, newip;
++
++    struct nf_conn *master = ct->master;
++
++    newdstip = master->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.ip;
++    newsrcip = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.ip;
++    //FIXME (how to port that ?)
++    //code from 2.4 : newip = (HOOK2MANIP(hooknum) == NF_NAT_MANIP_SRC) ? newsrcip : newdstip;
++    newip = newdstip;
++
++    pr_debug("newsrcip=%pI4, newdstip=%pI4, newip=%pI4\n",
++           &newsrcip, &newdstip, &newip);
++
++    mr.rangesize = 1;
++    // We don't want to manip the per-protocol, just the IPs. 
++    mr.range[0].flags = NF_NAT_RANGE_MAP_IPS;
++    mr.range[0].min_ip = mr.range[0].max_ip = newip;
++
++    nf_nat_setup_info(ct, &mr.range[0], NF_NAT_MANIP_DST);
++}
++
++
++static void __exit fini(void)
++{
++	nf_nat_rtsp_hook = NULL;
++        nf_nat_rtsp_hook_expectfn = NULL;
++	synchronize_net();
++}
++
++static int __init init(void)
++{
++	printk("nf_nat_rtsp v" IP_NF_RTSP_VERSION " loading\n");
++
++	BUG_ON(nf_nat_rtsp_hook);
++	nf_nat_rtsp_hook = help;
++        nf_nat_rtsp_hook_expectfn = &expected;
++
++	if (stunaddr != NULL)
++		extip = in_aton(stunaddr);
++
++	if (destaction != NULL) {
++	        if (strcmp(destaction, "auto") == 0)
++			dstact = DSTACT_AUTO;
++
++		if (strcmp(destaction, "strip") == 0)
++			dstact = DSTACT_STRIP;
++
++		if (strcmp(destaction, "none") == 0)
++			dstact = DSTACT_NONE;
++	}
++
++	return 0;
++}
++
++module_init(init);
++module_exit(fini);
+--- a/extensions/Kbuild
++++ b/extensions/Kbuild
+@@ -35,6 +35,7 @@ obj-${build_lscan}       += xt_lscan.o
+ obj-${build_pknock}      += pknock/
+ obj-${build_psd}         += xt_psd.o
+ obj-${build_quota2}      += xt_quota2.o
++obj-${build_rtsp}        += rtsp/
+ 
+ -include ${M}/*.Kbuild
+ -include ${M}/Kbuild.*
+--- a/mconfig
++++ b/mconfig
+@@ -26,3 +26,4 @@ build_lscan=m
+ build_pknock=m
+ build_psd=m
+ build_quota2=m
++build_rtsp=m