--- /dev/null
+diff -urN linux-2.4.32.orig/arch/mips/kernel/mips_ksyms.c linux-2.4.32/arch/mips/kernel/mips_ksyms.c
+--- linux-2.4.32.orig/arch/mips/kernel/mips_ksyms.c 2005-12-29 12:17:49.000000000 +0100
++++ linux-2.4.32/arch/mips/kernel/mips_ksyms.c 2005-12-29 12:18:26.000000000 +0100
+@@ -52,6 +52,7 @@
+ /*
+ * String functions
+ */
++EXPORT_SYMBOL_NOVERS(memchr);
+ EXPORT_SYMBOL_NOVERS(memcmp);
+ EXPORT_SYMBOL_NOVERS(memset);
+ EXPORT_SYMBOL_NOVERS(memcpy);
+diff -urN linux-2.4.32.orig/Documentation/Configure.help linux-2.4.32/Documentation/Configure.help
+--- linux-2.4.32.orig/Documentation/Configure.help 2005-12-29 12:17:55.000000000 +0100
++++ linux-2.4.32/Documentation/Configure.help 2005-12-29 12:18:26.000000000 +0100
+@@ -2817,6 +2817,14 @@
+ Documentation/modules.txt. If unsure, say `N'.
+
+
++RTSP protocol support
++CONFIG_IP_NF_RTSP
++ Support the RTSP protocol. This allows UDP transports to be setup
++ properly, including RTP and RDT.
++
++ If you want to compile it as a module, say 'M' here and read
++ Documentation/modules.txt. If unsure, say 'Y'.
++
+ IRC Send/Chat protocol support
+ CONFIG_IP_NF_IRC
+ There is a commonly-used extension to IRC called
+diff -urN linux-2.4.32.orig/include/linux/netfilter_helpers.h linux-2.4.32/include/linux/netfilter_helpers.h
+--- linux-2.4.32.orig/include/linux/netfilter_helpers.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.4.32/include/linux/netfilter_helpers.h 2005-12-29 12:18:26.000000000 +0100
+@@ -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 */
+diff -urN linux-2.4.32.orig/include/linux/netfilter_ipv4/ip_conntrack.h linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack.h
+--- linux-2.4.32.orig/include/linux/netfilter_ipv4/ip_conntrack.h 2005-12-29 12:17:55.000000000 +0100
++++ linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack.h 2005-12-29 12:18:26.000000000 +0100
+@@ -66,6 +66,7 @@
+ };
+
+ /* Add protocol helper include file here */
++#include <linux/netfilter_ipv4/ip_conntrack_rtsp.h>
+ #include <linux/netfilter_ipv4/ip_conntrack_amanda.h>
+
+ #include <linux/netfilter_ipv4/ip_conntrack_ftp.h>
+@@ -78,6 +79,7 @@
+ /* per expectation: application helper private data */
+ union ip_conntrack_expect_help {
+ /* insert conntrack helper private data (expect) here */
++ struct ip_ct_rtsp_expect exp_rtsp_info;
+ struct ip_ct_amanda_expect exp_amanda_info;
+ struct ip_ct_ftp_expect exp_ftp_info;
+ struct ip_ct_irc_expect exp_irc_info;
+@@ -96,6 +98,7 @@
+ /* per conntrack: application helper private data */
+ union ip_conntrack_help {
+ /* insert conntrack helper private data (master) here */
++ struct ip_ct_rtsp_master ct_rtsp_info;
+ struct ip_ct_ftp_master ct_ftp_info;
+ struct ip_ct_irc_master ct_irc_info;
+ struct ip_ct_pptp_master ct_pptp_info;
+diff -urN linux-2.4.32.orig/include/linux/netfilter_ipv4/ip_conntrack_rtsp.h linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack_rtsp.h
+--- linux-2.4.32.orig/include/linux/netfilter_ipv4/ip_conntrack_rtsp.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.4.32/include/linux/netfilter_ipv4/ip_conntrack_rtsp.h 2005-12-29 12:18:26.000000000 +0100
+@@ -0,0 +1,68 @@
++/*
++ * RTSP extension for IP connection tracking.
++ * (C) 2003 by Tom Marshall <tmarshall@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 */
++#define IP_NF_RTSP_VERSION "0.01"
++
++/* 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
++};
++
++/* This structure exists only once per master */
++struct ip_ct_rtsp_master
++{
++ /* Empty (?) */
++};
++
++
++#ifdef __KERNEL__
++
++#include <linux/netfilter_ipv4/lockhelp.h>
++
++#define RTSP_PORT 554
++
++/* Protects rtsp part of conntracks */
++DECLARE_LOCK_EXTERN(ip_rtsp_lock);
++
++#endif /* __KERNEL__ */
++
++#endif /* _IP_CONNTRACK_RTSP_H */
+diff -urN linux-2.4.32.orig/include/linux/netfilter_mime.h linux-2.4.32/include/linux/netfilter_mime.h
+--- linux-2.4.32.orig/include/linux/netfilter_mime.h 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.4.32/include/linux/netfilter_mime.h 2005-12-29 12:18:26.000000000 +0100
+@@ -0,0 +1,90 @@
++/*
++ * 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/kernel.h>
++#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 */
+diff -urN linux-2.4.32.orig/net/ipv4/netfilter/Config.in linux-2.4.32/net/ipv4/netfilter/Config.in
+--- linux-2.4.32.orig/net/ipv4/netfilter/Config.in 2005-12-29 12:17:55.000000000 +0100
++++ linux-2.4.32/net/ipv4/netfilter/Config.in 2005-12-29 12:20:42.000000000 +0100
+@@ -18,6 +18,7 @@
+ dep_tristate ' SIP protocol support' CONFIG_IP_NF_SIP $CONFIG_IP_NF_CONNTRACK
+ dep_tristate ' H.323 (netmeeting) support' CONFIG_IP_NF_H323 $CONFIG_IP_NF_CONNTRACK
+ dep_tristate ' MMS protocol support' CONFIG_IP_NF_MMS $CONFIG_IP_NF_CONNTRACK
++ dep_tristate ' RTSP protocol support' CONFIG_IP_NF_RTSP $CONFIG_IP_NF_CONNTRACK
+ fi
+
+ if [ "$CONFIG_EXPERIMENTAL" = "y" ]; then
+@@ -128,6 +129,13 @@
+ define_tristate CONFIG_IP_NF_NAT_MMS $CONFIG_IP_NF_NAT
+ fi
+ fi
++ if [ "$CONFIG_IP_NF_RTSP" = "m" ]; then
++ define_tristate CONFIG_IP_NF_NAT_RTSP m
++ else
++ if [ "$CONFIG_IP_NF_RTSP" = "y" ]; then
++ define_tristate CONFIG_IP_NF_NAT_RTSP $CONFIG_IP_NF_NAT
++ fi
++ fi
+ if [ "$CONFIG_IP_NF_AMANDA" = "m" ]; then
+ define_tristate CONFIG_IP_NF_NAT_AMANDA m
+ else
+diff -urN linux-2.4.32.orig/net/ipv4/netfilter/ip_conntrack_rtsp.c linux-2.4.32/net/ipv4/netfilter/ip_conntrack_rtsp.c
+--- linux-2.4.32.orig/net/ipv4/netfilter/ip_conntrack_rtsp.c 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.4.32/net/ipv4/netfilter/ip_conntrack_rtsp.c 2005-12-29 12:18:26.000000000 +0100
+@@ -0,0 +1,507 @@
++/*
++ * RTSP extension for IP connection tracking
++ * (C) 2003 by Tom Marshall <tmarshall@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 ip_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).
++ */
++
++#include <linux/config.h>
++#include <linux/module.h>
++#include <linux/netfilter.h>
++#include <linux/ip.h>
++#include <net/checksum.h>
++#include <net/tcp.h>
++
++#include <linux/netfilter_ipv4/lockhelp.h>
++#include <linux/netfilter_ipv4/ip_conntrack_helper.h>
++#include <linux/netfilter_ipv4/ip_conntrack_rtsp.h>
++
++#include <linux/ctype.h>
++#define NF_NEED_STRNCASECMP
++#define NF_NEED_STRTOU16
++#define NF_NEED_STRTOU32
++#define NF_NEED_NEXTLINE
++#include <linux/netfilter_helpers.h>
++#define NF_NEED_MIME_NEXTLINE
++#include <linux/netfilter_mime.h>
++
++#define MAX_SIMUL_SETUP 8 /* XXX: use max_outstanding */
++
++#define INFOP(fmt, args...) printk(KERN_INFO "%s: %s: " fmt, __FILE__, __FUNCTION__ , ## args)
++#ifdef IP_NF_RTSP_DEBUG
++#define DEBUGP(fmt, args...) printk(KERN_DEBUG "%s: %s: " fmt, __FILE__, __FUNCTION__ , ## args)
++#else
++#define DEBUGP(fmt, args...)
++#endif
++
++#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@real.com>");
++MODULE_DESCRIPTION("RTSP connection tracking module");
++MODULE_LICENSE("GPL");
++#ifdef MODULE_PARM
++MODULE_PARM(ports, "1-" __MODULE_STRING(MAX_PORTS) "i");
++MODULE_PARM_DESC(ports, "port numbers of RTSP servers");
++MODULE_PARM(max_outstanding, "i");
++MODULE_PARM_DESC(max_outstanding, "max number of outstanding SETUP requests per RTSP session");
++MODULE_PARM(setup_timeout, "i");
++MODULE_PARM_DESC(setup_timeout, "timeout on for unestablished data channels");
++#endif
++
++DECLARE_LOCK(ip_rtsp_lock);
++struct module* ip_conntrack_rtsp = THIS_MODULE;
++
++/*
++ * 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 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)
++ {
++ INFOP("!! overrun !!\n");
++ break;
++ }
++
++ if (nf_strncasecmp(ptcp+lineoff, "CSeq:", 5) == 0)
++ {
++ *pcseqoff = lineoff;
++ *pcseqlen = 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)
++ {
++ INFOP("sanity check failed\n");
++ return 0;
++ }
++ DEBUGP("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)
++ {
++ DEBUGP("multiple ports found, port %hu ignored\n", port);
++ }
++ else
++ {
++ 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)
++ {
++ DEBUGP("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;
++}
++
++/*** conntrack functions ***/
++
++/* outbound packet: client->server */
++static int
++help_out(const struct iphdr* iph, size_t pktlen,
++ struct ip_conntrack* ct, enum ip_conntrack_info ctinfo)
++{
++ int dir = CTINFO2DIR(ctinfo); /* = IP_CT_DIR_ORIGINAL */
++ struct tcphdr* tcph = (void*)iph + iph->ihl * 4;
++ uint tcplen = pktlen - iph->ihl * 4;
++ char* pdata = (char*)tcph + tcph->doff * 4;
++ uint datalen = tcplen - tcph->doff * 4;
++ uint dataoff = 0;
++
++ struct ip_conntrack_expect exp;
++
++ while (dataoff < datalen)
++ {
++ uint cmdoff = dataoff;
++ uint hdrsoff = 0;
++ uint hdrslen = 0;
++ uint cseqoff = 0;
++ uint cseqlen = 0;
++ uint lineoff = 0;
++ uint linelen = 0;
++ uint off;
++ int rc;
++
++ if (!rtsp_parse_message(pdata, datalen, &dataoff,
++ &hdrsoff, &hdrslen,
++ &cseqoff, &cseqlen))
++ {
++ break; /* not a valid message */
++ }
++
++ if (strncmp(pdata+cmdoff, "SETUP ", 6) != 0)
++ {
++ continue; /* not a SETUP message */
++ }
++ DEBUGP("found a setup message\n");
++
++ memset(&exp, 0, sizeof(exp));
++
++ off = 0;
++ while (nf_mime_nextline(pdata+hdrsoff, hdrslen, &off,
++ &lineoff, &linelen))
++ {
++ if (linelen == 0)
++ {
++ break;
++ }
++ if (off > hdrsoff+hdrslen)
++ {
++ INFOP("!! overrun !!");
++ break;
++ }
++
++ if (nf_strncasecmp(pdata+hdrsoff+lineoff, "Transport:", 10) == 0)
++ {
++ rtsp_parse_transport(pdata+hdrsoff+lineoff, linelen,
++ &exp.help.exp_rtsp_info);
++ }
++ }
++
++ if (exp.help.exp_rtsp_info.loport == 0)
++ {
++ DEBUGP("no udp transports found\n");
++ continue; /* no udp transports found */
++ }
++
++ DEBUGP("udp transport found, ports=(%d,%hu,%hu)\n",
++ (int)exp.help.exp_rtsp_info.pbtype,
++ exp.help.exp_rtsp_info.loport,
++ exp.help.exp_rtsp_info.hiport);
++
++ LOCK_BH(&ip_rtsp_lock);
++ exp.seq = ntohl(tcph->seq) + hdrsoff; /* mark all the headers */
++ exp.help.exp_rtsp_info.len = hdrslen;
++
++ exp.tuple.src.ip = ct->tuplehash[!dir].tuple.src.ip;
++ exp.mask.src.ip = 0xffffffff;
++ exp.tuple.dst.ip = ct->tuplehash[dir].tuple.src.ip;
++ exp.mask.dst.ip = 0xffffffff;
++ exp.tuple.dst.u.udp.port = exp.help.exp_rtsp_info.loport;
++ exp.mask.dst.u.udp.port = (exp.help.exp_rtsp_info.pbtype == pb_range) ? 0xfffe : 0xffff;
++ exp.tuple.dst.protonum = IPPROTO_UDP;
++ exp.mask.dst.protonum = 0xffff;
++
++ DEBUGP("expect_related %u.%u.%u.%u:%u-%u.%u.%u.%u:%u\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));
++
++ /* pass the request off to the nat helper */
++ rc = ip_conntrack_expect_related(ct, &exp);
++ UNLOCK_BH(&ip_rtsp_lock);
++ if (rc == 0)
++ {
++ DEBUGP("ip_conntrack_expect_related succeeded\n");
++ }
++ else
++ {
++ INFOP("ip_conntrack_expect_related failed (%d)\n", rc);
++ }
++ }
++
++ return NF_ACCEPT;
++}
++
++/* inbound packet: server->client */
++static int
++help_in(const struct iphdr* iph, size_t pktlen,
++ struct ip_conntrack* ct, enum ip_conntrack_info ctinfo)
++{
++ return NF_ACCEPT;
++}
++
++static int
++help(const struct iphdr* iph, size_t pktlen,
++ struct ip_conntrack* ct, enum ip_conntrack_info ctinfo)
++{
++ /* tcplen not negative guarenteed by ip_conntrack_tcp.c */
++ struct tcphdr* tcph = (void*)iph + iph->ihl * 4;
++ u_int32_t tcplen = pktlen - iph->ihl * 4;
++
++ /* 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)
++ {
++ DEBUGP("conntrackinfo = %u\n", ctinfo);
++ return NF_ACCEPT;
++ }
++
++ /* Not whole TCP header? */
++ if (tcplen < sizeof(struct tcphdr) || tcplen < tcph->doff * 4)
++ {
++ DEBUGP("tcplen = %u\n", (unsigned)tcplen);
++ return NF_ACCEPT;
++ }
++
++ /* 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;
++ }
++
++ switch (CTINFO2DIR(ctinfo))
++ {
++ case IP_CT_DIR_ORIGINAL:
++ help_out(iph, pktlen, ct, ctinfo);
++ break;
++ case IP_CT_DIR_REPLY:
++ help_in(iph, pktlen, ct, ctinfo);
++ break;
++ }
++
++ return NF_ACCEPT;
++}
++
++static struct ip_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++)
++ {
++ DEBUGP("unregistering port %d\n", ports[i]);
++ ip_conntrack_helper_unregister(&rtsp_helpers[i]);
++ }
++}
++
++static int __init
++init(void)
++{
++ int i, ret;
++ struct ip_conntrack_helper *hlpr;
++ char *tmpname;
++
++ printk("ip_conntrack_rtsp v" IP_NF_RTSP_VERSION " loading\n");
++
++ if (max_outstanding < 1)
++ {
++ printk("ip_conntrack_rtsp: max_outstanding must be a positive integer\n");
++ return -EBUSY;
++ }
++ if (setup_timeout < 0)
++ {
++ printk("ip_conntrack_rtsp: setup_timeout must be a positive integer\n");
++ return -EBUSY;
++ }
++
++ /* 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 ip_conntrack_helper));
++ 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 = 0xFFFF;
++ hlpr->max_expected = max_outstanding;
++ hlpr->timeout = setup_timeout;
++ hlpr->flags = IP_CT_HELPER_F_REUSE_EXPECT;
++ hlpr->me = ip_conntrack_rtsp;
++ 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;
++
++ DEBUGP("port #%d: %d\n", i, ports[i]);
++
++ ret = ip_conntrack_helper_register(hlpr);
++
++ if (ret)
++ {
++ printk("ip_conntrack_rtsp: ERROR registering port %d\n", ports[i]);
++ fini();
++ return -EBUSY;
++ }
++ num_ports++;
++ }
++ return 0;
++}
++
++#ifdef CONFIG_IP_NF_NAT_NEEDED
++EXPORT_SYMBOL(ip_rtsp_lock);
++#endif
++
++module_init(init);
++module_exit(fini);
+diff -urN linux-2.4.32.orig/net/ipv4/netfilter/ip_nat_rtsp.c linux-2.4.32/net/ipv4/netfilter/ip_nat_rtsp.c
+--- linux-2.4.32.orig/net/ipv4/netfilter/ip_nat_rtsp.c 1970-01-01 01:00:00.000000000 +0100
++++ linux-2.4.32/net/ipv4/netfilter/ip_nat_rtsp.c 2005-12-29 12:18:26.000000000 +0100
+@@ -0,0 +1,621 @@
++/*
++ * RTSP extension for TCP NAT alteration
++ * (C) 2003 by Tom Marshall <tmarshall@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 ip_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 <linux/netfilter_ipv4.h>
++#include <linux/ip.h>
++#include <linux/tcp.h>
++#include <linux/kernel.h>
++#include <net/tcp.h>
++#include <linux/netfilter_ipv4/ip_nat.h>
++#include <linux/netfilter_ipv4/ip_nat_helper.h>
++#include <linux/netfilter_ipv4/ip_nat_rule.h>
++#include <linux/netfilter_ipv4/ip_conntrack_rtsp.h>
++#include <linux/netfilter_ipv4/ip_conntrack_helper.h>
++
++#include <linux/inet.h>
++#include <linux/ctype.h>
++#define NF_NEED_STRNCASECMP
++#define NF_NEED_STRTOU16
++#include <linux/netfilter_helpers.h>
++#define NF_NEED_MIME_NEXTLINE
++#include <linux/netfilter_mime.h>
++
++#define INFOP(fmt, args...) printk(KERN_INFO "%s: %s: " fmt, __FILE__, __FUNCTION__ , ## args)
++#ifdef IP_NF_RTSP_DEBUG
++#define DEBUGP(fmt, args...) printk(KERN_DEBUG "%s: %s: " fmt, __FILE__, __FUNCTION__ , ## args)
++#else
++#define DEBUGP(fmt, args...)
++#endif
++
++#define MAX_PORTS 8
++#define DSTACT_AUTO 0
++#define DSTACT_STRIP 1
++#define DSTACT_NONE 2
++
++static int ports[MAX_PORTS];
++static char* stunaddr = NULL;
++static char* destaction = NULL;
++
++static int num_ports = 0;
++static u_int32_t extip = 0;
++static int dstact = 0;
++
++MODULE_AUTHOR("Tom Marshall <tmarshall@real.com>");
++MODULE_DESCRIPTION("RTSP network address translation module");
++MODULE_LICENSE("GPL");
++#ifdef MODULE_PARM
++MODULE_PARM(ports, "1-" __MODULE_STRING(MAX_PORTS) "i");
++MODULE_PARM_DESC(ports, "port numbers of RTSP servers");
++MODULE_PARM(stunaddr, "s");
++MODULE_PARM_DESC(stunaddr, "Address for detecting STUN");
++MODULE_PARM(destaction, "s");
++MODULE_PARM_DESC(destaction, "Action for destination parameter (auto/strip/none)");
++#endif
++
++/* protects rtsp part of conntracks */
++DECLARE_LOCK_EXTERN(ip_rtsp_lock);
++
++#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 = (struct iphdr*)skb->nh.iph;
++ struct tcphdr* tcph = (struct tcphdr*)((char*)iph + iph->ihl*4);
++
++ *pptcpdata = (char*)tcph + tcph->doff*4;
++ *ptcpdatalen = ((char*)skb->h.raw + skb->len) - *pptcpdata;
++}
++
++/*** nat functions ***/
++
++/*
++ * Mangle the "Transport:" header:
++ * - Replace all occurences of "client_port=<spec>"
++ * - Handle destination parameter
++ *
++ * In:
++ * ct, ctinfo = conntrack context
++ * pskb = 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(struct ip_conntrack* ct, enum ip_conntrack_info ctinfo,
++ struct ip_conntrack_expect* exp,
++ struct sk_buff** pskb, 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 ip_ct_rtsp_expect* prtspexp = &exp->help.exp_rtsp_info;
++ struct ip_conntrack_tuple t;
++
++ char szextaddr[15+1];
++ uint extaddrlen;
++ int is_stun;
++
++ get_skb_tcpdata(*pskb, &ptcp, &tcplen);
++ ptran = ptcp+tranoff;
++
++ if (tranoff+tranlen > tcplen || tcplen-tranoff < tranlen ||
++ tranlen < 10 || !iseol(ptran[tranlen-1]) ||
++ nf_strncasecmp(ptran, "Transport:", 10) != 0)
++ {
++ INFOP("sanity check failed\n");
++ return 0;
++ }
++ off += 10;
++ SKIP_WSPACE(ptcp+tranoff, tranlen, off);
++
++ newip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip;
++ t = exp->tuple;
++ t.dst.ip = newip;
++
++ extaddrlen = extip ? sprintf(szextaddr, "%u.%u.%u.%u", NIPQUAD(extip))
++ : sprintf(szextaddr, "%u.%u.%u.%u", NIPQUAD(newip));
++ DEBUGP("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 (ip_conntrack_change_expect(exp, &t) == 0)
++ {
++ DEBUGP("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 (ip_conntrack_change_expect(exp, &t) == 0)
++ {
++ hiport = loport + ~exp->mask.dst.u.udp.port;
++ DEBUGP("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 (ip_conntrack_change_expect(exp, &t) == 0)
++ {
++ DEBUGP("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 (ip_conntrack_change_expect(exp, &t) == 0)
++ {
++ DEBUGP("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 (!ip_nat_mangle_tcp_packet(pskb, ct, ctinfo,
++ off, diff, NULL, 0))
++ {
++ /* mangle failed, all we can do is bail */
++ return 0;
++ }
++ get_skb_tcpdata(*pskb, &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)
++ {
++ DEBUGP("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 (!ip_nat_mangle_tcp_packet(pskb, ct, ctinfo,
++ origoff, origlen, rbuf, rbuflen))
++ {
++ /* mangle failed, all we can do is bail */
++ return 0;
++ }
++ get_skb_tcpdata(*pskb, &ptcp, &tcplen);
++ ptran = ptcp+tranoff;
++ tranlen -= diff;
++ nextparamoff -= diff;
++ nextfieldoff -= diff;
++ }
++ }
++
++ off = nextfieldoff;
++ }
++
++ off = nextparamoff;
++ }
++
++ return 1;
++}
++
++static unsigned int
++expected(struct sk_buff **pskb, uint hooknum, struct ip_conntrack* ct, struct ip_nat_info* info)
++{
++ struct ip_nat_multi_range mr;
++ u_int32_t newdstip, newsrcip, newip;
++
++ struct ip_conntrack *master = master_ct(ct);
++
++ IP_NF_ASSERT(info);
++ IP_NF_ASSERT(master);
++
++ IP_NF_ASSERT(!(info->initialized & (1 << HOOK2MANIP(hooknum))));
++
++ newdstip = master->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip;
++ newsrcip = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip;
++ newip = (HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC) ? newsrcip : newdstip;
++
++ DEBUGP("newsrcip=%u.%u.%u.%u, newdstip=%u.%u.%u.%u, newip=%u.%u.%u.%u\n",
++ NIPQUAD(newsrcip), NIPQUAD(newdstip), NIPQUAD(newip));
++
++ mr.rangesize = 1;
++ /* We don't want to manip the per-protocol, just the IPs. */
++ mr.range[0].flags = IP_NAT_RANGE_MAP_IPS;
++ mr.range[0].min_ip = mr.range[0].max_ip = newip;
++
++ return ip_nat_setup_info(ct, &mr, hooknum);
++}
++
++static uint
++help_out(struct ip_conntrack* ct, enum ip_conntrack_info ctinfo,
++ struct ip_conntrack_expect* exp, struct sk_buff** pskb)
++{
++ 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);
++
++ struct ip_ct_rtsp_expect* prtspexp = &exp->help.exp_rtsp_info;
++
++ get_skb_tcpdata(*pskb, &ptcp, &tcplen);
++
++ hdrsoff = exp->seq - ntohl(tcph->seq);
++ hdrslen = prtspexp->len;
++ off = hdrsoff;
++
++ while (nf_mime_nextline(ptcp, hdrsoff+hdrslen, &off, &lineoff, &linelen))
++ {
++ if (linelen == 0)
++ {
++ break;
++ }
++ if (off > hdrsoff+hdrslen)
++ {
++ INFOP("!! overrun !!");
++ break;
++ }
++ DEBUGP("hdr: len=%u, %.*s", linelen, (int)linelen, ptcp+lineoff);
++
++ if (nf_strncasecmp(ptcp+lineoff, "Transport:", 10) == 0)
++ {
++ uint oldtcplen = tcplen;
++ if (!rtsp_mangle_tran(ct, ctinfo, exp, pskb, lineoff, linelen))
++ {
++ break;
++ }
++ get_skb_tcpdata(*pskb, &ptcp, &tcplen);
++ hdrslen -= (oldtcplen-tcplen);
++ off -= (oldtcplen-tcplen);
++ lineoff -= (oldtcplen-tcplen);
++ linelen -= (oldtcplen-tcplen);
++ DEBUGP("rep: len=%u, %.*s", linelen, (int)linelen, ptcp+lineoff);
++ }
++ }
++
++ return NF_ACCEPT;
++}
++
++static uint
++help_in(struct ip_conntrack* ct, enum ip_conntrack_info ctinfo,
++ struct ip_conntrack_expect* exp, struct sk_buff** pskb)
++{
++ /* XXX: unmangle */
++ return NF_ACCEPT;
++}
++
++static uint
++help(struct ip_conntrack* ct,
++ struct ip_conntrack_expect* exp,
++ struct ip_nat_info* info,
++ enum ip_conntrack_info ctinfo,
++ unsigned int hooknum,
++ struct sk_buff** pskb)
++{
++ struct iphdr* iph = (struct iphdr*)(*pskb)->nh.iph;
++ struct tcphdr* tcph = (struct tcphdr*)((char*)iph + iph->ihl * 4);
++ uint datalen;
++ int dir;
++ struct ip_ct_rtsp_expect* ct_rtsp_info;
++ int rc = NF_ACCEPT;
++
++ if (ct == NULL || exp == NULL || info == NULL || pskb == NULL)
++ {
++ DEBUGP("!! null ptr (%p,%p,%p,%p) !!\n", ct, exp, info, pskb);
++ return NF_ACCEPT;
++ }
++
++ ct_rtsp_info = &exp->help.exp_rtsp_info;
++
++ /*
++ * Only mangle things once: original direction in POST_ROUTING
++ * and reply direction on PRE_ROUTING.
++ */
++ dir = CTINFO2DIR(ctinfo);
++ if (!((hooknum == NF_IP_POST_ROUTING && dir == IP_CT_DIR_ORIGINAL)
++ || (hooknum == NF_IP_PRE_ROUTING && dir == IP_CT_DIR_REPLY)))
++ {
++ DEBUGP("Not touching dir %s at hook %s\n",
++ dir == IP_CT_DIR_ORIGINAL ? "ORIG" : "REPLY",
++ hooknum == NF_IP_POST_ROUTING ? "POSTROUTING"
++ : hooknum == NF_IP_PRE_ROUTING ? "PREROUTING"
++ : hooknum == NF_IP_LOCAL_OUT ? "OUTPUT" : "???");
++ return NF_ACCEPT;
++ }
++ DEBUGP("got beyond not touching\n");
++
++ datalen = (*pskb)->len - iph->ihl * 4 - tcph->doff * 4;
++
++ LOCK_BH(&ip_rtsp_lock);
++ /* Ensure the packet contains all of the marked data */
++ if (!between(exp->seq + ct_rtsp_info->len,
++ ntohl(tcph->seq), ntohl(tcph->seq) + datalen))
++ {
++ /* Partial retransmission? Probably a hacker. */
++ if (net_ratelimit())
++ {
++ INFOP("partial packet %u/%u in %u/%u\n",
++ exp->seq, ct_rtsp_info->len, ntohl(tcph->seq), ntohl(tcph->seq) + datalen);
++ }
++ UNLOCK_BH(&ip_rtsp_lock);
++ return NF_DROP;
++ }
++
++ switch (dir)
++ {
++ case IP_CT_DIR_ORIGINAL:
++ rc = help_out(ct, ctinfo, exp, pskb);
++ break;
++ case IP_CT_DIR_REPLY:
++ rc = help_in(ct, ctinfo, exp, pskb);
++ break;
++ }
++ UNLOCK_BH(&ip_rtsp_lock);
++
++ return rc;
++}
++
++static struct ip_nat_helper ip_nat_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++)
++ {
++ DEBUGP("unregistering helper for port %d\n", ports[i]);
++ ip_nat_helper_unregister(&ip_nat_rtsp_helpers[i]);
++ }
++}
++
++static int __init
++init(void)
++{
++ int ret = 0;
++ int i;
++ struct ip_nat_helper* hlpr;
++ char* tmpname;
++
++ printk("ip_nat_rtsp v" IP_NF_RTSP_VERSION " loading\n");
++
++ if (ports[0] == 0)
++ {
++ ports[0] = RTSP_PORT;
++ }
++
++ for (i = 0; (i < MAX_PORTS) && ports[i] != 0; i++)
++ {
++ hlpr = &ip_nat_rtsp_helpers[i];
++ memset(hlpr, 0, sizeof(struct ip_nat_helper));
++
++ hlpr->tuple.dst.protonum = IPPROTO_TCP;
++ hlpr->tuple.src.u.tcp.port = htons(ports[i]);
++ hlpr->mask.src.u.tcp.port = 0xFFFF;
++ hlpr->mask.dst.protonum = 0xFFFF;
++ hlpr->help = help;
++ hlpr->flags = 0;
++ hlpr->me = THIS_MODULE;
++ hlpr->expect = expected;
++
++ tmpname = &rtsp_names[i][0];
++ if (ports[i] == RTSP_PORT)
++ {
++ sprintf(tmpname, "rtsp");
++ }
++ else
++ {
++ sprintf(tmpname, "rtsp-%d", i);
++ }
++ hlpr->name = tmpname;
++
++ DEBUGP("registering helper for port %d: name %s\n", ports[i], hlpr->name);
++ ret = ip_nat_helper_register(hlpr);
++
++ if (ret)
++ {
++ printk("ip_nat_rtsp: error registering helper for port %d\n", ports[i]);
++ fini();
++ return 1;
++ }
++ num_ports++;
++ }
++ 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 ret;
++}
++
++module_init(init);
++module_exit(fini);
+diff -urN linux-2.4.32.orig/net/ipv4/netfilter/Makefile linux-2.4.32/net/ipv4/netfilter/Makefile
+--- linux-2.4.32.orig/net/ipv4/netfilter/Makefile 2005-12-29 12:17:55.000000000 +0100
++++ linux-2.4.32/net/ipv4/netfilter/Makefile 2005-12-29 12:18:26.000000000 +0100
+@@ -32,6 +32,14 @@
+ obj-$(CONFIG_IP_NF_CONNTRACK) += ip_conntrack.o
+
+ # connection tracking helpers
++
++# rtsp protocol support
++obj-$(CONFIG_IP_NF_RTSP) += ip_conntrack_rtsp.o
++ifdef CONFIG_IP_NF_NAT_RTSP
++ export-objs += ip_conntrack_rtsp.o
++endif
++obj-$(CONFIG_IP_NF_NAT_RTSP) += ip_nat_rtsp.o
++
+ obj-$(CONFIG_IP_NF_AMANDA) += ip_conntrack_amanda.o
+ ifdef CONFIG_IP_NF_AMANDA
+ export-objs += ip_conntrack_amanda.o
projects / openwrt / openwrt.git / commitdiff