linux-mtx-2: fixed acm driver to produce more stable behaviour with HSDPA datacards

1 files changed, 5092 insertions, 0 deletions

diff --git a/packages/linux/linux-mtx-1-2.4.27/48-pptp.patch b/packages/linux/linux-mtx-1-2.4.27/48-pptp.patch
new file mode 100644
index 0000000000..5896f90370
--- /dev/null
+++ b/packages/linux/linux-mtx-1-2.4.27/48-pptp.patch
@@ -0,0 +1,5092 @@
+diff -uNr linux_org/Documentation/Configure.help linux/Documentation/Configure.help
+--- linux_org/Documentation/Configure.help	2006-10-27 14:08:20.000000000 +0200
++++ linux/Documentation/Configure.help	2006-10-27 14:11:52.000000000 +0200
+@@ -2848,6 +2848,31 @@
+   If you want to compile it as a module, say M here and read
+   <file:Documentation/modules.txt>.  If unsure, say `Y'.
+ 
++PPTP conntrack and NAT support
++CONFIG_IP_NF_PPTP
++  This module adds support for PPTP (Point to Point Tunnelling Protocol, 
++  RFC2637) conncection tracking and NAT. 
++
++  If you are running PPTP sessions over a stateful firewall or NAT box,
++  you may want to enable this feature.  
++
++  Please note that not all PPTP modes of operation are supported yet.
++  For more info, read top of the file net/ipv4/netfilter/ip_conntrack_pptp.c
++
++  If you want to compile it as a module, say M here and read
++  Documentation/modules.txt.  If unsure, say `N'.
++
++GRE protocol conntrack and NAT support
++CONFIG_IP_NF_CT_PROTO_GRE
++  This module adds generic support for connection tracking and NAT of the
++  GRE protocol (RFC1701, RFC2784).  Please note that this will only work
++  with GRE connections using the key field of the GRE header.
++
++  You will need GRE support to enable PPTP support.
++
++  If you want to compile it as a module, say `M' here and read
++  Documentation/modules.txt.  If unsire, say `N'.
++
+ User space queueing via NETLINK
+ CONFIG_IP_NF_QUEUE
+   Netfilter has the ability to queue packets to user space: the
+diff -uNr linux_org/include/linux/netfilter_ipv4/ip_conntrack.h linux/include/linux/netfilter_ipv4/ip_conntrack.h
+--- linux_org/include/linux/netfilter_ipv4/ip_conntrack.h	2004-11-24 12:13:57.000000000 +0100
++++ linux/include/linux/netfilter_ipv4/ip_conntrack.h	2006-10-27 14:11:52.000000000 +0200
+@@ -50,19 +50,23 @@
+ 
+ #include <linux/netfilter_ipv4/ip_conntrack_tcp.h>
+ #include <linux/netfilter_ipv4/ip_conntrack_icmp.h>
++#include <linux/netfilter_ipv4/ip_conntrack_proto_gre.h>
+ 
+ /* per conntrack: protocol private data */
+ union ip_conntrack_proto {
+ 	/* insert conntrack proto private data here */
++	struct ip_ct_gre gre;
+ 	struct ip_ct_tcp tcp;
+ 	struct ip_ct_icmp icmp;
+ };
+ 
+ union ip_conntrack_expect_proto {
+ 	/* insert expect proto private data here */
++	struct ip_ct_gre_expect gre;
+ };
+ 
+ /* Add protocol helper include file here */
++#include <linux/netfilter_ipv4/ip_conntrack_pptp.h>
+ #include <linux/netfilter_ipv4/ip_conntrack_amanda.h>
+ 
+ #include <linux/netfilter_ipv4/ip_conntrack_ftp.h>
+@@ -71,6 +75,7 @@
+ /* per expectation: application helper private data */
+ union ip_conntrack_expect_help {
+ 	/* insert conntrack helper private data (expect) here */
++	struct ip_ct_pptp_expect exp_pptp_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;
+@@ -85,16 +90,19 @@
+ /* per conntrack: application helper private data */
+ union ip_conntrack_help {
+ 	/* insert conntrack helper private data (master) here */
++	struct ip_ct_pptp_master ct_pptp_info;
+ 	struct ip_ct_ftp_master ct_ftp_info;
+ 	struct ip_ct_irc_master ct_irc_info;
+ };
+ 
+ #ifdef CONFIG_IP_NF_NAT_NEEDED
+ #include <linux/netfilter_ipv4/ip_nat.h>
++#include <linux/netfilter_ipv4/ip_nat_pptp.h>
+ 
+ /* per conntrack: nat application helper private data */
+ union ip_conntrack_nat_help {
+ 	/* insert nat helper private data here */
++	struct ip_nat_pptp nat_pptp_info;
+ };
+ #endif
+ 
+diff -uNr linux_org/include/linux/netfilter_ipv4/ip_conntrack_pptp.h linux/include/linux/netfilter_ipv4/ip_conntrack_pptp.h
+--- linux_org/include/linux/netfilter_ipv4/ip_conntrack_pptp.h	1970-01-01 01:00:00.000000000 +0100
++++ linux/include/linux/netfilter_ipv4/ip_conntrack_pptp.h	2006-10-27 14:11:52.000000000 +0200
+@@ -0,0 +1,313 @@
++/* PPTP constants and structs */
++#ifndef _CONNTRACK_PPTP_H
++#define _CONNTRACK_PPTP_H
++
++/* state of the control session */
++enum pptp_ctrlsess_state {
++	PPTP_SESSION_NONE,			/* no session present */
++	PPTP_SESSION_ERROR,			/* some session error */
++	PPTP_SESSION_STOPREQ,			/* stop_sess request seen */
++	PPTP_SESSION_REQUESTED,			/* start_sess request seen */
++	PPTP_SESSION_CONFIRMED,			/* session established */
++};
++
++/* state of the call inside the control session */
++enum pptp_ctrlcall_state {
++	PPTP_CALL_NONE,
++	PPTP_CALL_ERROR,
++	PPTP_CALL_OUT_REQ,
++	PPTP_CALL_OUT_CONF,
++	PPTP_CALL_IN_REQ,
++	PPTP_CALL_IN_REP,
++	PPTP_CALL_IN_CONF,
++	PPTP_CALL_CLEAR_REQ,
++};
++
++
++/* conntrack private data */
++struct ip_ct_pptp_master {
++	enum pptp_ctrlsess_state sstate;	/* session state */
++
++	/* everything below is going to be per-expectation in newnat,
++	 * since there could be more than one call within one session */
++	enum pptp_ctrlcall_state cstate;	/* call state */
++	u_int16_t pac_call_id;			/* call id of PAC, host byte order */
++	u_int16_t pns_call_id;			/* call id of PNS, host byte order */
++};
++
++/* conntrack_expect private member */
++struct ip_ct_pptp_expect {
++	enum pptp_ctrlcall_state cstate; 	/* call state */
++	u_int16_t pac_call_id;			/* call id of PAC */
++	u_int16_t pns_call_id;			/* call id of PNS */
++};
++
++
++#ifdef __KERNEL__
++
++#include <linux/netfilter_ipv4/lockhelp.h>
++DECLARE_LOCK_EXTERN(ip_pptp_lock);
++
++#define IP_CONNTR_PPTP		PPTP_CONTROL_PORT
++
++union pptp_ctrl_union {
++                void				*rawreq;
++		struct PptpStartSessionRequest	*sreq;
++		struct PptpStartSessionReply	*srep;
++		struct PptpStopSessionReqest	*streq;
++		struct PptpStopSessionReply	*strep;
++                struct PptpOutCallRequest       *ocreq;
++                struct PptpOutCallReply         *ocack;
++                struct PptpInCallRequest        *icreq;
++                struct PptpInCallReply          *icack;
++                struct PptpInCallConnected      *iccon;
++		struct PptpClearCallRequest	*clrreq;
++                struct PptpCallDisconnectNotify *disc;
++                struct PptpWanErrorNotify       *wanerr;
++                struct PptpSetLinkInfo          *setlink;
++};
++
++
++
++#define PPTP_CONTROL_PORT	1723
++
++#define PPTP_PACKET_CONTROL	1
++#define PPTP_PACKET_MGMT	2
++
++#define PPTP_MAGIC_COOKIE	0x1a2b3c4d
++
++struct pptp_pkt_hdr {
++	__u16	packetLength;
++	__u16	packetType;
++	__u32	magicCookie;
++};
++
++/* PptpControlMessageType values */
++#define PPTP_START_SESSION_REQUEST	1
++#define PPTP_START_SESSION_REPLY	2
++#define PPTP_STOP_SESSION_REQUEST	3
++#define PPTP_STOP_SESSION_REPLY		4
++#define PPTP_ECHO_REQUEST		5
++#define PPTP_ECHO_REPLY			6
++#define PPTP_OUT_CALL_REQUEST		7
++#define PPTP_OUT_CALL_REPLY		8
++#define PPTP_IN_CALL_REQUEST		9
++#define PPTP_IN_CALL_REPLY		10
++#define PPTP_IN_CALL_CONNECT		11
++#define PPTP_CALL_CLEAR_REQUEST		12
++#define PPTP_CALL_DISCONNECT_NOTIFY	13
++#define PPTP_WAN_ERROR_NOTIFY		14
++#define PPTP_SET_LINK_INFO		15
++
++#define PPTP_MSG_MAX			15
++
++/* PptpGeneralError values */
++#define PPTP_ERROR_CODE_NONE		0
++#define PPTP_NOT_CONNECTED		1
++#define PPTP_BAD_FORMAT			2
++#define PPTP_BAD_VALUE			3
++#define PPTP_NO_RESOURCE		4
++#define PPTP_BAD_CALLID			5
++#define PPTP_REMOVE_DEVICE_ERROR	6
++
++struct PptpControlHeader {
++	__u16	messageType;
++	__u16	reserved;
++};
++
++/* FramingCapability Bitmap Values */
++#define PPTP_FRAME_CAP_ASYNC		0x1
++#define PPTP_FRAME_CAP_SYNC		0x2
++
++/* BearerCapability Bitmap Values */
++#define PPTP_BEARER_CAP_ANALOG		0x1
++#define PPTP_BEARER_CAP_DIGITAL		0x2
++
++struct PptpStartSessionRequest {
++	__u16	protocolVersion;
++	__u8	reserved1;
++	__u8	reserved2;
++	__u32	framingCapability;
++	__u32	bearerCapability;
++	__u16	maxChannels;
++	__u16	firmwareRevision;
++	__u8	hostName[64];
++	__u8	vendorString[64];
++};
++
++/* PptpStartSessionResultCode Values */
++#define PPTP_START_OK			1
++#define PPTP_START_GENERAL_ERROR	2
++#define PPTP_START_ALREADY_CONNECTED	3
++#define PPTP_START_NOT_AUTHORIZED	4
++#define PPTP_START_UNKNOWN_PROTOCOL	5
++
++struct PptpStartSessionReply {
++	__u16	protocolVersion;
++	__u8	resultCode;
++	__u8	generalErrorCode;
++	__u32	framingCapability;
++	__u32	bearerCapability;
++	__u16	maxChannels;
++	__u16	firmwareRevision;
++	__u8	hostName[64];
++	__u8	vendorString[64];
++};
++
++/* PptpStopReasons */
++#define PPTP_STOP_NONE			1
++#define PPTP_STOP_PROTOCOL		2
++#define PPTP_STOP_LOCAL_SHUTDOWN	3
++
++struct PptpStopSessionRequest {
++	__u8	reason;
++};
++
++/* PptpStopSessionResultCode */
++#define PPTP_STOP_OK			1
++#define PPTP_STOP_GENERAL_ERROR		2
++
++struct PptpStopSessionReply {
++	__u8	resultCode;
++	__u8	generalErrorCode;
++};
++
++struct PptpEchoRequest {
++	__u32 identNumber;
++};
++
++/* PptpEchoReplyResultCode */
++#define PPTP_ECHO_OK			1
++#define PPTP_ECHO_GENERAL_ERROR		2
++
++struct PptpEchoReply {
++	__u32	identNumber;
++	__u8	resultCode;
++	__u8	generalErrorCode;
++	__u16	reserved;
++};
++
++/* PptpFramingType */
++#define PPTP_ASYNC_FRAMING		1
++#define PPTP_SYNC_FRAMING		2
++#define PPTP_DONT_CARE_FRAMING		3
++
++/* PptpCallBearerType */
++#define PPTP_ANALOG_TYPE		1
++#define PPTP_DIGITAL_TYPE		2
++#define PPTP_DONT_CARE_BEARER_TYPE	3
++
++struct PptpOutCallRequest {
++	__u16	callID;
++	__u16	callSerialNumber;
++	__u32	minBPS;
++	__u32	maxBPS;
++	__u32	bearerType;
++	__u32	framingType;
++	__u16	packetWindow;
++	__u16	packetProcDelay;
++	__u16	reserved1;
++	__u16	phoneNumberLength;
++	__u16	reserved2;
++	__u8	phoneNumber[64];
++	__u8	subAddress[64];
++};
++
++/* PptpCallResultCode */
++#define PPTP_OUTCALL_CONNECT		1
++#define PPTP_OUTCALL_GENERAL_ERROR	2
++#define PPTP_OUTCALL_NO_CARRIER		3
++#define PPTP_OUTCALL_BUSY		4
++#define PPTP_OUTCALL_NO_DIAL_TONE	5
++#define PPTP_OUTCALL_TIMEOUT		6
++#define PPTP_OUTCALL_DONT_ACCEPT	7
++
++struct PptpOutCallReply {
++	__u16	callID;
++	__u16	peersCallID;
++	__u8	resultCode;
++	__u8	generalErrorCode;
++	__u16	causeCode;
++	__u32	connectSpeed;
++	__u16	packetWindow;
++	__u16	packetProcDelay;
++	__u32	physChannelID;
++};
++
++struct PptpInCallRequest {
++	__u16	callID;
++	__u16	callSerialNumber;
++	__u32	callBearerType;
++	__u32	physChannelID;
++	__u16	dialedNumberLength;
++	__u16	dialingNumberLength;
++	__u8	dialedNumber[64];
++	__u8	dialingNumber[64];
++	__u8	subAddress[64];
++};
++
++/* PptpInCallResultCode */
++#define PPTP_INCALL_ACCEPT		1
++#define PPTP_INCALL_GENERAL_ERROR	2
++#define PPTP_INCALL_DONT_ACCEPT		3
++
++struct PptpInCallReply {
++	__u16	callID;
++	__u16	peersCallID;
++	__u8	resultCode;
++	__u8	generalErrorCode;
++	__u16	packetWindow;
++	__u16	packetProcDelay;
++	__u16	reserved;
++};
++
++struct PptpInCallConnected {
++	__u16	peersCallID;
++	__u16	reserved;
++	__u32	connectSpeed;
++	__u16	packetWindow;
++	__u16	packetProcDelay;
++	__u32	callFramingType;
++};
++
++struct PptpClearCallRequest {
++	__u16	callID;
++	__u16	reserved;
++};
++
++struct PptpCallDisconnectNotify {
++	__u16	callID;
++	__u8	resultCode;
++	__u8	generalErrorCode;
++	__u16	causeCode;
++	__u16	reserved;
++	__u8	callStatistics[128];
++};
++
++struct PptpWanErrorNotify {
++	__u16	peersCallID;
++	__u16	reserved;
++	__u32	crcErrors;
++	__u32	framingErrors;
++	__u32	hardwareOverRuns;
++	__u32	bufferOverRuns;
++	__u32	timeoutErrors;
++	__u32	alignmentErrors;
++};
++
++struct PptpSetLinkInfo {
++	__u16	peersCallID;
++	__u16	reserved;
++	__u32	sendAccm;
++	__u32	recvAccm;
++};
++
++
++struct pptp_priv_data {
++	__u16	call_id;
++	__u16	mcall_id;
++	__u16	pcall_id;
++};
++
++#endif /* __KERNEL__ */
++#endif /* _CONNTRACK_PPTP_H */
+diff -uNr linux_org/include/linux/netfilter_ipv4/ip_conntrack_proto_gre.h linux/include/linux/netfilter_ipv4/ip_conntrack_proto_gre.h
+--- linux_org/include/linux/netfilter_ipv4/ip_conntrack_proto_gre.h	1970-01-01 01:00:00.000000000 +0100
++++ linux/include/linux/netfilter_ipv4/ip_conntrack_proto_gre.h	2006-10-27 14:11:52.000000000 +0200
+@@ -0,0 +1,123 @@
++#ifndef _CONNTRACK_PROTO_GRE_H
++#define _CONNTRACK_PROTO_GRE_H
++#include <asm/byteorder.h>
++
++/* GRE PROTOCOL HEADER */
++
++/* GRE Version field */
++#define GRE_VERSION_1701	0x0
++#define GRE_VERSION_PPTP	0x1
++
++/* GRE Protocol field */
++#define GRE_PROTOCOL_PPTP	0x880B
++
++/* GRE Flags */
++#define GRE_FLAG_C		0x80
++#define GRE_FLAG_R		0x40
++#define GRE_FLAG_K		0x20
++#define GRE_FLAG_S		0x10
++#define GRE_FLAG_A		0x80
++
++#define GRE_IS_C(f)	((f)&GRE_FLAG_C)
++#define GRE_IS_R(f)	((f)&GRE_FLAG_R)
++#define GRE_IS_K(f)	((f)&GRE_FLAG_K)
++#define GRE_IS_S(f)	((f)&GRE_FLAG_S)
++#define GRE_IS_A(f)	((f)&GRE_FLAG_A)
++
++/* GRE is a mess: Four different standards */
++struct gre_hdr {
++#if defined(__LITTLE_ENDIAN_BITFIELD)
++	__u16	rec:3,
++		srr:1,
++		seq:1,
++		key:1,
++		routing:1,
++		csum:1,
++		version:3,
++		reserved:4,
++		ack:1;
++#elif defined(__BIG_ENDIAN_BITFIELD)
++	__u16	csum:1,
++		routing:1,
++		key:1,
++		seq:1,
++		srr:1,
++		rec:3,
++		ack:1,
++		reserved:4,
++		version:3;
++#else
++#error "Adjust your <asm/byteorder.h> defines"
++#endif
++	__u16	protocol;
++};
++
++/* modified GRE header for PPTP */
++struct gre_hdr_pptp {
++	__u8  flags;		/* bitfield */
++	__u8  version;		/* should be GRE_VERSION_PPTP */
++	__u16 protocol;		/* should be GRE_PROTOCOL_PPTP */
++	__u16 payload_len;	/* size of ppp payload, not inc. gre header */
++	__u16 call_id;		/* peer's call_id for this session */
++	__u32 seq;		/* sequence number.  Present if S==1 */
++	__u32 ack;		/* seq number of highest packet recieved by */
++				/*  sender in this session */
++};
++
++
++/* this is part of ip_conntrack */
++struct ip_ct_gre {
++	unsigned int stream_timeout;
++	unsigned int timeout;
++};
++
++/* this is part of ip_conntrack_expect */
++struct ip_ct_gre_expect {
++	struct ip_ct_gre_keymap *keymap_orig, *keymap_reply;
++};
++
++#ifdef __KERNEL__
++struct ip_conntrack_expect;
++
++/* structure for original <-> reply keymap */
++struct ip_ct_gre_keymap {
++	struct list_head list;
++
++	struct ip_conntrack_tuple tuple;
++};
++
++
++/* add new tuple->key_reply pair to keymap */
++int ip_ct_gre_keymap_add(struct ip_conntrack_expect *exp,
++			 struct ip_conntrack_tuple *t,
++			 int reply);
++
++/* change an existing keymap entry */
++void ip_ct_gre_keymap_change(struct ip_ct_gre_keymap *km,
++			     struct ip_conntrack_tuple *t);
++
++/* delete keymap entries */
++void ip_ct_gre_keymap_destroy(struct ip_conntrack_expect *exp);
++
++
++/* get pointer to gre key, if present */
++static inline u_int32_t *gre_key(struct gre_hdr *greh)
++{
++	if (!greh->key)
++		return NULL;
++	if (greh->csum || greh->routing)
++		return (u_int32_t *) (greh+sizeof(*greh)+4);
++	return (u_int32_t *) (greh+sizeof(*greh));
++}
++
++/* get pointer ot gre csum, if present */
++static inline u_int16_t *gre_csum(struct gre_hdr *greh)
++{
++	if (!greh->csum)
++		return NULL;
++	return (u_int16_t *) (greh+sizeof(*greh));
++}
++
++#endif /* __KERNEL__ */
++
++#endif /* _CONNTRACK_PROTO_GRE_H */
+diff -uNr linux_org/include/linux/netfilter_ipv4/ip_conntrack_tuple.h linux/include/linux/netfilter_ipv4/ip_conntrack_tuple.h
+--- linux_org/include/linux/netfilter_ipv4/ip_conntrack_tuple.h	2003-11-17 02:07:46.000000000 +0100
++++ linux/include/linux/netfilter_ipv4/ip_conntrack_tuple.h	2006-10-27 14:11:52.000000000 +0200
+@@ -14,7 +14,7 @@
+ union ip_conntrack_manip_proto
+ {
+ 	/* Add other protocols here. */
+-	u_int16_t all;
++	u_int32_t all;
+ 
+ 	struct {
+ 		u_int16_t port;
+@@ -25,6 +25,9 @@
+ 	struct {
+ 		u_int16_t id;
+ 	} icmp;
++	struct {
++		u_int32_t key;
++	} gre;
+ };
+ 
+ /* The manipulable part of the tuple. */
+@@ -44,7 +47,7 @@
+ 		u_int32_t ip;
+ 		union {
+ 			/* Add other protocols here. */
+-			u_int16_t all;
++			u_int64_t all;
+ 
+ 			struct {
+ 				u_int16_t port;
+@@ -55,6 +58,11 @@
+ 			struct {
+ 				u_int8_t type, code;
+ 			} icmp;
++			struct {
++				u_int16_t protocol;
++				u_int8_t version;
++				u_int32_t key;
++			} gre;
+ 		} u;
+ 
+ 		/* The protocol. */
+@@ -80,10 +88,16 @@
+ #ifdef __KERNEL__
+ 
+ #define DUMP_TUPLE(tp)						\
+-DEBUGP("tuple %p: %u %u.%u.%u.%u:%hu -> %u.%u.%u.%u:%hu\n",	\
++DEBUGP("tuple %p: %u %u.%u.%u.%u:%u -> %u.%u.%u.%u:%u\n",	\
+        (tp), (tp)->dst.protonum,				\
+-       NIPQUAD((tp)->src.ip), ntohs((tp)->src.u.all),		\
+-       NIPQUAD((tp)->dst.ip), ntohs((tp)->dst.u.all))
++       NIPQUAD((tp)->src.ip), ntohl((tp)->src.u.all),		\
++       NIPQUAD((tp)->dst.ip), ntohl((tp)->dst.u.all))
++
++#define DUMP_TUPLE_RAW(x) 						\
++	DEBUGP("tuple %p: %u %u.%u.%u.%u:0x%08x -> %u.%u.%u.%u:0x%08x\n",\
++	(x), (x)->dst.protonum,						\
++	NIPQUAD((x)->src.ip), ntohl((x)->src.u.all), 			\
++	NIPQUAD((x)->dst.ip), ntohl((x)->dst.u.all))
+ 
+ #define CTINFO2DIR(ctinfo) ((ctinfo) >= IP_CT_IS_REPLY ? IP_CT_DIR_REPLY : IP_CT_DIR_ORIGINAL)
+ 
+diff -uNr linux_org/include/linux/netfilter_ipv4/ip_conntrack_tuple.h.orig linux/include/linux/netfilter_ipv4/ip_conntrack_tuple.h.orig
+--- linux_org/include/linux/netfilter_ipv4/ip_conntrack_tuple.h.orig	1970-01-01 01:00:00.000000000 +0100
++++ linux/include/linux/netfilter_ipv4/ip_conntrack_tuple.h.orig	2003-11-17 02:07:46.000000000 +0100
+@@ -0,0 +1,139 @@
++#ifndef _IP_CONNTRACK_TUPLE_H
++#define _IP_CONNTRACK_TUPLE_H
++
++/* A `tuple' is a structure containing the information to uniquely
++  identify a connection.  ie. if two packets have the same tuple, they
++  are in the same connection; if not, they are not.
++
++  We divide the structure along "manipulatable" and
++  "non-manipulatable" lines, for the benefit of the NAT code.
++*/
++
++/* The protocol-specific manipulable parts of the tuple: always in
++   network order! */
++union ip_conntrack_manip_proto
++{
++	/* Add other protocols here. */
++	u_int16_t all;
++
++	struct {
++		u_int16_t port;
++	} tcp;
++	struct {
++		u_int16_t port;
++	} udp;
++	struct {
++		u_int16_t id;
++	} icmp;
++};
++
++/* The manipulable part of the tuple. */
++struct ip_conntrack_manip
++{
++	u_int32_t ip;
++	union ip_conntrack_manip_proto u;
++};
++
++/* This contains the information to distinguish a connection. */
++struct ip_conntrack_tuple
++{
++	struct ip_conntrack_manip src;
++
++	/* These are the parts of the tuple which are fixed. */
++	struct {
++		u_int32_t ip;
++		union {
++			/* Add other protocols here. */
++			u_int16_t all;
++
++			struct {
++				u_int16_t port;
++			} tcp;
++			struct {
++				u_int16_t port;
++			} udp;
++			struct {
++				u_int8_t type, code;
++			} icmp;
++		} u;
++
++		/* The protocol. */
++		u_int16_t protonum;
++	} dst;
++};
++
++/* This is optimized opposed to a memset of the whole structure.  Everything we
++ * really care about is the  source/destination unions */
++#define IP_CT_TUPLE_U_BLANK(tuple) 				\
++	do {							\
++		(tuple)->src.u.all = 0;				\
++		(tuple)->dst.u.all = 0;				\
++	} while (0)
++
++enum ip_conntrack_dir
++{
++	IP_CT_DIR_ORIGINAL,
++	IP_CT_DIR_REPLY,
++	IP_CT_DIR_MAX
++};
++
++#ifdef __KERNEL__
++
++#define DUMP_TUPLE(tp)						\
++DEBUGP("tuple %p: %u %u.%u.%u.%u:%hu -> %u.%u.%u.%u:%hu\n",	\
++       (tp), (tp)->dst.protonum,				\
++       NIPQUAD((tp)->src.ip), ntohs((tp)->src.u.all),		\
++       NIPQUAD((tp)->dst.ip), ntohs((tp)->dst.u.all))
++
++#define CTINFO2DIR(ctinfo) ((ctinfo) >= IP_CT_IS_REPLY ? IP_CT_DIR_REPLY : IP_CT_DIR_ORIGINAL)
++
++/* If we're the first tuple, it's the original dir. */
++#define DIRECTION(h) ((enum ip_conntrack_dir)(&(h)->ctrack->tuplehash[1] == (h)))
++
++/* Connections have two entries in the hash table: one for each way */
++struct ip_conntrack_tuple_hash
++{
++	struct list_head list;
++
++	struct ip_conntrack_tuple tuple;
++
++	/* this == &ctrack->tuplehash[DIRECTION(this)]. */
++	struct ip_conntrack *ctrack;
++};
++
++#endif /* __KERNEL__ */
++
++static inline int ip_ct_tuple_src_equal(const struct ip_conntrack_tuple *t1,
++				        const struct ip_conntrack_tuple *t2)
++{
++	return t1->src.ip == t2->src.ip
++		&& t1->src.u.all == t2->src.u.all;
++}
++
++static inline int ip_ct_tuple_dst_equal(const struct ip_conntrack_tuple *t1,
++				        const struct ip_conntrack_tuple *t2)
++{
++	return t1->dst.ip == t2->dst.ip
++		&& t1->dst.u.all == t2->dst.u.all
++		&& t1->dst.protonum == t2->dst.protonum;
++}
++
++static inline int ip_ct_tuple_equal(const struct ip_conntrack_tuple *t1,
++				    const struct ip_conntrack_tuple *t2)
++{
++	return ip_ct_tuple_src_equal(t1, t2) && ip_ct_tuple_dst_equal(t1, t2);
++}
++
++static inline int ip_ct_tuple_mask_cmp(const struct ip_conntrack_tuple *t,
++				       const struct ip_conntrack_tuple *tuple,
++				       const struct ip_conntrack_tuple *mask)
++{
++	return !(((t->src.ip ^ tuple->src.ip) & mask->src.ip)
++		 || ((t->dst.ip ^ tuple->dst.ip) & mask->dst.ip)
++		 || ((t->src.u.all ^ tuple->src.u.all) & mask->src.u.all)
++		 || ((t->dst.u.all ^ tuple->dst.u.all) & mask->dst.u.all)
++		 || ((t->dst.protonum ^ tuple->dst.protonum)
++		     & mask->dst.protonum));
++}
++
++#endif /* _IP_CONNTRACK_TUPLE_H */
+diff -uNr linux_org/include/linux/netfilter_ipv4/ip_nat_pptp.h linux/include/linux/netfilter_ipv4/ip_nat_pptp.h
+--- linux_org/include/linux/netfilter_ipv4/ip_nat_pptp.h	1970-01-01 01:00:00.000000000 +0100
++++ linux/include/linux/netfilter_ipv4/ip_nat_pptp.h	2006-10-27 14:11:52.000000000 +0200
+@@ -0,0 +1,11 @@
++/* PPTP constants and structs */
++#ifndef _NAT_PPTP_H
++#define _NAT_PPTP_H
++
++/* conntrack private data */
++struct ip_nat_pptp {
++	u_int16_t pns_call_id;		/* NAT'ed PNS call id */
++	u_int16_t pac_call_id;		/* NAT'ed PAC call id */
++};
++
++#endif /* _NAT_PPTP_H */
+diff -uNr linux_org/net/ipv4/netfilter/Config.in linux/net/ipv4/netfilter/Config.in
+--- linux_org/net/ipv4/netfilter/Config.in	2003-08-13 19:19:30.000000000 +0200
++++ linux/net/ipv4/netfilter/Config.in	2006-10-27 14:11:52.000000000 +0200
+@@ -7,6 +7,11 @@
+ tristate 'Connection tracking (required for masq/NAT)' CONFIG_IP_NF_CONNTRACK
+ if [ "$CONFIG_IP_NF_CONNTRACK" != "n" ]; then
+   dep_tristate '  FTP protocol support' CONFIG_IP_NF_FTP $CONFIG_IP_NF_CONNTRACK
++  dep_tristate '  GRE protocol support' CONFIG_IP_NF_CT_PROTO_GRE $CONFIG_IP_NF_CONNTRACK
++  dep_tristate '  PPTP protocol support' CONFIG_IP_NF_PPTP $CONFIG_IP_NF_CONNTRACK
++  if [ "$CONFIG_IP_NF_PPTP" != "n" ]; then
++	bool   '    PPTP verbose debug' CONFIG_IP_NF_PPTP_DEBUG
++  fi
+   dep_tristate '  Amanda protocol support' CONFIG_IP_NF_AMANDA $CONFIG_IP_NF_CONNTRACK
+   dep_tristate '  TFTP protocol support' CONFIG_IP_NF_TFTP $CONFIG_IP_NF_CONNTRACK
+   dep_tristate '  IRC protocol support' CONFIG_IP_NF_IRC $CONFIG_IP_NF_CONNTRACK
+@@ -67,6 +72,20 @@
+         fi
+       fi
+       bool '    NAT of local connections (READ HELP)' CONFIG_IP_NF_NAT_LOCAL
++      if [ "$CONFIG_IP_NF_PPTP" = "m" ]; then
++        define_tristate CONFIG_IP_NF_NAT_PPTP m
++      else
++        if [ "$CONFIG_IP_NF_PPTP" = "y" ]; then
++          define_tristate CONFIG_IP_NF_NAT_PPTP $CONFIG_IP_NF_NAT
++        fi
++      fi
++      if [ "$CONFIG_IP_NF_CT_PROTO_GRE" = "m" ]; then
++        define_tristate CONFIG_IP_NF_NAT_PROTO_GRE m
++      else
++        if [ "$CONFIG_IP_NF_CT_PROTO_GRE" = "y" ]; then
++	  define_tristate CONFIG_IP_NF_NAT_PROTO_GRE $CONFIG_IP_NF_NAT
++	fi
++      fi
+       if [ "$CONFIG_EXPERIMENTAL" = "y" ]; then
+         dep_tristate '    Basic SNMP-ALG support (EXPERIMENTAL)' CONFIG_IP_NF_NAT_SNMP_BASIC $CONFIG_IP_NF_NAT
+       fi
+diff -uNr linux_org/net/ipv4/netfilter/Makefile linux/net/ipv4/netfilter/Makefile
+--- linux_org/net/ipv4/netfilter/Makefile	2003-08-13 19:19:30.000000000 +0200
++++ linux/net/ipv4/netfilter/Makefile	2006-10-27 14:11:52.000000000 +0200
+@@ -30,8 +30,21 @@
+ 
+ # connection tracking
+ obj-$(CONFIG_IP_NF_CONNTRACK) += ip_conntrack.o
++ 
++# connection tracking protocol helpers
++obj-$(CONFIG_IP_NF_CT_PROTO_GRE) += ip_conntrack_proto_gre.o
++ifdef CONFIG_IP_NF_CT_PROTO_GRE
++	export-objs += ip_conntrack_proto_gre.o
++endif
++
++# NAT protocol helpers
++obj-$(CONFIG_IP_NF_NAT_PROTO_GRE) += ip_nat_proto_gre.o
+ 
+ # connection tracking helpers
++obj-$(CONFIG_IP_NF_PPTP) += ip_conntrack_pptp.o
++ifdef CONFIG_IP_NF_NAT_PPTP
++	export-objs += ip_conntrack_pptp.o
++endif
+ obj-$(CONFIG_IP_NF_AMANDA) += ip_conntrack_amanda.o
+ ifdef CONFIG_IP_NF_AMANDA
+ 	export-objs += ip_conntrack_amanda.o
+@@ -49,6 +62,7 @@
+ endif
+ 
+ # NAT helpers 
++obj-$(CONFIG_IP_NF_NAT_PPTP) += ip_nat_pptp.o
+ obj-$(CONFIG_IP_NF_NAT_AMANDA) += ip_nat_amanda.o
+ obj-$(CONFIG_IP_NF_NAT_TFTP) += ip_nat_tftp.o
+ obj-$(CONFIG_IP_NF_NAT_FTP) += ip_nat_ftp.o
+diff -uNr linux_org/net/ipv4/netfilter/ip_conntrack_core.c linux/net/ipv4/netfilter/ip_conntrack_core.c
+--- linux_org/net/ipv4/netfilter/ip_conntrack_core.c	2004-11-24 12:14:04.000000000 +0100
++++ linux/net/ipv4/netfilter/ip_conntrack_core.c	2006-10-27 14:11:52.000000000 +0200
+@@ -142,6 +142,8 @@
+ 	tuple->dst.ip = iph->daddr;
+ 	tuple->dst.protonum = iph->protocol;
+ 
++	tuple->src.u.all = tuple->dst.u.all = 0;
++
+ 	ret = protocol->pkt_to_tuple((u_int32_t *)iph + iph->ihl,
+ 				     len - 4*iph->ihl,
+ 				     tuple);
+@@ -157,6 +159,8 @@
+ 	inverse->dst.ip = orig->src.ip;
+ 	inverse->dst.protonum = orig->dst.protonum;
+ 
++	inverse->src.u.all = inverse->dst.u.all = 0;
++
+ 	return protocol->invert_tuple(inverse, orig);
+ }
+ 
+@@ -945,8 +949,8 @@
+ 	 * so there is no need to use the tuple lock too */
+ 
+ 	DEBUGP("ip_conntrack_expect_related %p\n", related_to);
+-	DEBUGP("tuple: "); DUMP_TUPLE(&expect->tuple);
+-	DEBUGP("mask:  "); DUMP_TUPLE(&expect->mask);
++	DEBUGP("tuple: "); DUMP_TUPLE_RAW(&expect->tuple);
++	DEBUGP("mask:  "); DUMP_TUPLE_RAW(&expect->mask);
+ 
+ 	old = LIST_FIND(&ip_conntrack_expect_list, resent_expect,
+ 		        struct ip_conntrack_expect *, &expect->tuple, 
+@@ -1063,15 +1067,14 @@
+ 
+ 	MUST_BE_READ_LOCKED(&ip_conntrack_lock);
+ 	WRITE_LOCK(&ip_conntrack_expect_tuple_lock);
+-
+ 	DEBUGP("change_expect:\n");
+-	DEBUGP("exp tuple: "); DUMP_TUPLE(&expect->tuple);
+-	DEBUGP("exp mask:  "); DUMP_TUPLE(&expect->mask);
+-	DEBUGP("newtuple:  "); DUMP_TUPLE(newtuple);
++	DEBUGP("exp tuple: "); DUMP_TUPLE_RAW(&expect->tuple);
++	DEBUGP("exp mask:  "); DUMP_TUPLE_RAW(&expect->mask);
++	DEBUGP("newtuple:  "); DUMP_TUPLE_RAW(newtuple);
+ 	if (expect->ct_tuple.dst.protonum == 0) {
+ 		/* Never seen before */
+ 		DEBUGP("change expect: never seen before\n");
+-		if (!ip_ct_tuple_equal(&expect->tuple, newtuple) 
++		if (!ip_ct_tuple_mask_cmp(&expect->tuple, newtuple, &expect->mask)
+ 		    && LIST_FIND(&ip_conntrack_expect_list, expect_clash,
+ 			         struct ip_conntrack_expect *, newtuple, &expect->mask)) {
+ 			/* Force NAT to find an unused tuple */
+diff -uNr linux_org/net/ipv4/netfilter/ip_conntrack_core.c.orig linux/net/ipv4/netfilter/ip_conntrack_core.c.orig
+--- linux_org/net/ipv4/netfilter/ip_conntrack_core.c.orig	1970-01-01 01:00:00.000000000 +0100
++++ linux/net/ipv4/netfilter/ip_conntrack_core.c.orig	2004-11-24 12:14:04.000000000 +0100
+@@ -0,0 +1,1446 @@
++/* Connection state tracking for netfilter.  This is separated from,
++   but required by, the NAT layer; it can also be used by an iptables
++   extension. */
++
++/* (c) 1999 Paul `Rusty' Russell.  Licenced under the GNU General
++ * Public Licence. 
++ *
++ * 23 Apr 2001: Harald Welte <laforge@gnumonks.org>
++ * 	- new API and handling of conntrack/nat helpers
++ * 	- now capable of multiple expectations for one master
++ * 16 Jul 2002: Harald Welte <laforge@gnumonks.org>
++ * 	- add usage/reference counts to ip_conntrack_expect
++ *	- export ip_conntrack[_expect]_{find_get,put} functions
++ * */
++
++#include <linux/version.h>
++#include <linux/config.h>
++#include <linux/types.h>
++#include <linux/ip.h>
++#include <linux/netfilter.h>
++#include <linux/netfilter_ipv4.h>
++#include <linux/module.h>
++#include <linux/skbuff.h>
++#include <linux/proc_fs.h>
++#include <linux/vmalloc.h>
++#include <linux/brlock.h>
++#include <net/checksum.h>
++#include <linux/stddef.h>
++#include <linux/sysctl.h>
++#include <linux/slab.h>
++#include <linux/random.h>
++#include <linux/jhash.h>
++/* For ERR_PTR().  Yeah, I know... --RR */
++#include <linux/fs.h>
++
++/* This rwlock protects the main hash table, protocol/helper/expected
++   registrations, conntrack timers*/
++#define ASSERT_READ_LOCK(x) MUST_BE_READ_LOCKED(&ip_conntrack_lock)
++#define ASSERT_WRITE_LOCK(x) MUST_BE_WRITE_LOCKED(&ip_conntrack_lock)
++
++#include <linux/netfilter_ipv4/ip_conntrack.h>
++#include <linux/netfilter_ipv4/ip_conntrack_protocol.h>
++#include <linux/netfilter_ipv4/ip_conntrack_helper.h>
++#include <linux/netfilter_ipv4/ip_conntrack_core.h>
++#include <linux/netfilter_ipv4/listhelp.h>
++
++#define IP_CONNTRACK_VERSION	"2.1"
++
++#if 0
++#define DEBUGP printk
++#else
++#define DEBUGP(format, args...)
++#endif
++
++DECLARE_RWLOCK(ip_conntrack_lock);
++DECLARE_RWLOCK(ip_conntrack_expect_tuple_lock);
++
++void (*ip_conntrack_destroyed)(struct ip_conntrack *conntrack) = NULL;
++LIST_HEAD(ip_conntrack_expect_list);
++LIST_HEAD(protocol_list);
++static LIST_HEAD(helpers);
++unsigned int ip_conntrack_htable_size = 0;
++int ip_conntrack_max = 0;
++static atomic_t ip_conntrack_count = ATOMIC_INIT(0);
++struct list_head *ip_conntrack_hash;
++static kmem_cache_t *ip_conntrack_cachep;
++
++extern struct ip_conntrack_protocol ip_conntrack_generic_protocol;
++
++static inline int proto_cmpfn(const struct ip_conntrack_protocol *curr,
++			      u_int8_t protocol)
++{
++	return protocol == curr->proto;
++}
++
++struct ip_conntrack_protocol *__ip_ct_find_proto(u_int8_t protocol)
++{
++	struct ip_conntrack_protocol *p;
++
++	MUST_BE_READ_LOCKED(&ip_conntrack_lock);
++	p = LIST_FIND(&protocol_list, proto_cmpfn,
++		      struct ip_conntrack_protocol *, protocol);
++	if (!p)
++		p = &ip_conntrack_generic_protocol;
++
++	return p;
++}
++
++struct ip_conntrack_protocol *ip_ct_find_proto(u_int8_t protocol)
++{
++	struct ip_conntrack_protocol *p;
++
++	READ_LOCK(&ip_conntrack_lock);
++	p = __ip_ct_find_proto(protocol);
++	READ_UNLOCK(&ip_conntrack_lock);
++	return p;
++}
++
++inline void 
++ip_conntrack_put(struct ip_conntrack *ct)
++{
++	IP_NF_ASSERT(ct);
++	IP_NF_ASSERT(ct->infos[0].master);
++	/* nf_conntrack_put wants to go via an info struct, so feed it
++           one at random. */
++	nf_conntrack_put(&ct->infos[0]);
++}
++
++static int ip_conntrack_hash_rnd_initted;
++static unsigned int ip_conntrack_hash_rnd;
++
++static u_int32_t
++hash_conntrack(const struct ip_conntrack_tuple *tuple)
++{
++#if 0
++	dump_tuple(tuple);
++#endif
++	return (jhash_3words(tuple->src.ip,
++	                     (tuple->dst.ip ^ tuple->dst.protonum),
++	                     (tuple->src.u.all | (tuple->dst.u.all << 16)),
++	                     ip_conntrack_hash_rnd) % ip_conntrack_htable_size);
++}
++
++inline int
++get_tuple(const struct iphdr *iph, size_t len,
++	  struct ip_conntrack_tuple *tuple,
++	  struct ip_conntrack_protocol *protocol)
++{
++	int ret;
++
++	/* Never happen */
++	if (iph->frag_off & htons(IP_OFFSET)) {
++		printk("ip_conntrack_core: Frag of proto %u.\n",
++		       iph->protocol);
++		return 0;
++	}
++	/* Guarantee 8 protocol bytes: if more wanted, use len param */
++	else if (iph->ihl * 4 + 8 > len)
++		return 0;
++
++	tuple->src.ip = iph->saddr;
++	tuple->dst.ip = iph->daddr;
++	tuple->dst.protonum = iph->protocol;
++
++	ret = protocol->pkt_to_tuple((u_int32_t *)iph + iph->ihl,
++				     len - 4*iph->ihl,
++				     tuple);
++	return ret;
++}
++
++static int
++invert_tuple(struct ip_conntrack_tuple *inverse,
++	     const struct ip_conntrack_tuple *orig,
++	     const struct ip_conntrack_protocol *protocol)
++{
++	inverse->src.ip = orig->dst.ip;
++	inverse->dst.ip = orig->src.ip;
++	inverse->dst.protonum = orig->dst.protonum;
++
++	return protocol->invert_tuple(inverse, orig);
++}
++
++
++/* ip_conntrack_expect helper functions */
++
++/* Compare tuple parts depending on mask. */
++static inline int expect_cmp(const struct ip_conntrack_expect *i,
++			     const struct ip_conntrack_tuple *tuple)
++{
++	MUST_BE_READ_LOCKED(&ip_conntrack_expect_tuple_lock);
++	return ip_ct_tuple_mask_cmp(tuple, &i->tuple, &i->mask);
++}
++
++static void
++destroy_expect(struct ip_conntrack_expect *exp)
++{
++	DEBUGP("destroy_expect(%p) use=%d\n", exp, atomic_read(&exp->use));
++	IP_NF_ASSERT(atomic_read(&exp->use) == 0);
++	IP_NF_ASSERT(!timer_pending(&exp->timeout));
++
++	kfree(exp);
++}
++
++inline void ip_conntrack_expect_put(struct ip_conntrack_expect *exp)
++{
++	IP_NF_ASSERT(exp);
++
++	if (atomic_dec_and_test(&exp->use)) {
++		/* usage count dropped to zero */
++		destroy_expect(exp);
++	}
++}
++
++static inline struct ip_conntrack_expect *
++__ip_ct_expect_find(const struct ip_conntrack_tuple *tuple)
++{
++	MUST_BE_READ_LOCKED(&ip_conntrack_lock);
++	MUST_BE_READ_LOCKED(&ip_conntrack_expect_tuple_lock);
++	return LIST_FIND(&ip_conntrack_expect_list, expect_cmp, 
++			 struct ip_conntrack_expect *, tuple);
++}
++
++/* Find a expectation corresponding to a tuple. */
++struct ip_conntrack_expect *
++ip_conntrack_expect_find_get(const struct ip_conntrack_tuple *tuple)
++{
++	struct ip_conntrack_expect *exp;
++
++	READ_LOCK(&ip_conntrack_lock);
++	READ_LOCK(&ip_conntrack_expect_tuple_lock);
++	exp = __ip_ct_expect_find(tuple);
++	if (exp)
++		atomic_inc(&exp->use);
++	READ_UNLOCK(&ip_conntrack_expect_tuple_lock);
++	READ_UNLOCK(&ip_conntrack_lock);
++
++	return exp;
++}
++
++/* remove one specific expectation from all lists and drop refcount,
++ * does _NOT_ delete the timer. */
++static void __unexpect_related(struct ip_conntrack_expect *expect)
++{
++	DEBUGP("unexpect_related(%p)\n", expect);
++	MUST_BE_WRITE_LOCKED(&ip_conntrack_lock);
++
++	/* we're not allowed to unexpect a confirmed expectation! */
++	IP_NF_ASSERT(!expect->sibling);
++
++	/* delete from global and local lists */
++	list_del(&expect->list);
++	list_del(&expect->expected_list);
++
++	/* decrement expect-count of master conntrack */
++	if (expect->expectant)
++		expect->expectant->expecting--;
++
++	ip_conntrack_expect_put(expect);
++}
++
++/* remove one specific expecatation from all lists, drop refcount
++ * and expire timer. 
++ * This function can _NOT_ be called for confirmed expects! */
++static void unexpect_related(struct ip_conntrack_expect *expect)
++{
++	IP_NF_ASSERT(expect->expectant);
++	IP_NF_ASSERT(expect->expectant->helper);
++	/* if we are supposed to have a timer, but we can't delete
++	 * it: race condition.  __unexpect_related will
++	 * be calledd by timeout function */
++	if (expect->expectant->helper->timeout
++	    && !del_timer(&expect->timeout))
++		return;
++
++	__unexpect_related(expect);
++}
++
++/* delete all unconfirmed expectations for this conntrack */
++static void remove_expectations(struct ip_conntrack *ct, int drop_refcount)
++{
++	struct list_head *exp_entry, *next;
++	struct ip_conntrack_expect *exp;
++
++	DEBUGP("remove_expectations(%p)\n", ct);
++
++	list_for_each_safe(exp_entry, next, &ct->sibling_list) {
++		exp = list_entry(exp_entry, struct ip_conntrack_expect,
++				 expected_list);
++
++		/* we skip established expectations, as we want to delete
++		 * the un-established ones only */
++		if (exp->sibling) {
++			DEBUGP("remove_expectations: skipping established %p of %p\n", exp->sibling, ct);
++			if (drop_refcount) {
++				/* Indicate that this expectations parent is dead */
++				ip_conntrack_put(exp->expectant);
++				exp->expectant = NULL;
++			}
++			continue;
++		}
++
++		IP_NF_ASSERT(list_inlist(&ip_conntrack_expect_list, exp));
++		IP_NF_ASSERT(exp->expectant == ct);
++
++		/* delete expectation from global and private lists */
++		unexpect_related(exp);
++	}
++}
++
++static void
++clean_from_lists(struct ip_conntrack *ct)
++{
++	unsigned int ho, hr;
++	
++	DEBUGP("clean_from_lists(%p)\n", ct);
++	MUST_BE_WRITE_LOCKED(&ip_conntrack_lock);
++
++	ho = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
++	hr = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
++	LIST_DELETE(&ip_conntrack_hash[ho], &ct->tuplehash[IP_CT_DIR_ORIGINAL]);
++	LIST_DELETE(&ip_conntrack_hash[hr], &ct->tuplehash[IP_CT_DIR_REPLY]);
++
++	/* Destroy all un-established, pending expectations */
++	remove_expectations(ct, 1);
++}
++
++static void
++destroy_conntrack(struct nf_conntrack *nfct)
++{
++	struct ip_conntrack *ct = (struct ip_conntrack *)nfct, *master = NULL;
++	struct ip_conntrack_protocol *proto;
++
++	DEBUGP("destroy_conntrack(%p)\n", ct);
++	IP_NF_ASSERT(atomic_read(&nfct->use) == 0);
++	IP_NF_ASSERT(!timer_pending(&ct->timeout));
++
++	/* To make sure we don't get any weird locking issues here:
++	 * destroy_conntrack() MUST NOT be called with a write lock
++	 * to ip_conntrack_lock!!! -HW */
++	proto = ip_ct_find_proto(ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.protonum);
++	if (proto && proto->destroy)
++		proto->destroy(ct);
++
++	if (ip_conntrack_destroyed)
++		ip_conntrack_destroyed(ct);
++
++	WRITE_LOCK(&ip_conntrack_lock);
++	/* Make sure don't leave any orphaned expectations lying around */
++	if (ct->expecting)
++		remove_expectations(ct, 1);
++
++	/* Delete our master expectation */
++	if (ct->master) {
++		if (ct->master->expectant) {
++			/* can't call __unexpect_related here,
++			 * since it would screw up expect_list */
++			list_del(&ct->master->expected_list);
++			master = ct->master->expectant;
++		}
++		kfree(ct->master);
++	}
++	WRITE_UNLOCK(&ip_conntrack_lock);
++
++	if (master)
++		ip_conntrack_put(master);
++
++	DEBUGP("destroy_conntrack: returning ct=%p to slab\n", ct);
++	kmem_cache_free(ip_conntrack_cachep, ct);
++	atomic_dec(&ip_conntrack_count);
++}
++
++static void death_by_timeout(unsigned long ul_conntrack)
++{
++	struct ip_conntrack *ct = (void *)ul_conntrack;
++
++	WRITE_LOCK(&ip_conntrack_lock);
++	clean_from_lists(ct);
++	WRITE_UNLOCK(&ip_conntrack_lock);
++	ip_conntrack_put(ct);
++}
++
++static inline int
++conntrack_tuple_cmp(const struct ip_conntrack_tuple_hash *i,
++		    const struct ip_conntrack_tuple *tuple,
++		    const struct ip_conntrack *ignored_conntrack)
++{
++	MUST_BE_READ_LOCKED(&ip_conntrack_lock);
++	return i->ctrack != ignored_conntrack
++		&& ip_ct_tuple_equal(tuple, &i->tuple);
++}
++
++static struct ip_conntrack_tuple_hash *
++__ip_conntrack_find(const struct ip_conntrack_tuple *tuple,
++		    const struct ip_conntrack *ignored_conntrack)
++{
++	struct ip_conntrack_tuple_hash *h;
++	unsigned int hash = hash_conntrack(tuple);
++
++	MUST_BE_READ_LOCKED(&ip_conntrack_lock);
++	h = LIST_FIND(&ip_conntrack_hash[hash],
++		      conntrack_tuple_cmp,
++		      struct ip_conntrack_tuple_hash *,
++		      tuple, ignored_conntrack);
++	return h;
++}
++
++/* Find a connection corresponding to a tuple. */
++struct ip_conntrack_tuple_hash *
++ip_conntrack_find_get(const struct ip_conntrack_tuple *tuple,
++		      const struct ip_conntrack *ignored_conntrack)
++{
++	struct ip_conntrack_tuple_hash *h;
++
++	READ_LOCK(&ip_conntrack_lock);
++	h = __ip_conntrack_find(tuple, ignored_conntrack);
++	if (h)
++		atomic_inc(&h->ctrack->ct_general.use);
++	READ_UNLOCK(&ip_conntrack_lock);
++
++	return h;
++}
++
++static inline struct ip_conntrack *
++__ip_conntrack_get(struct nf_ct_info *nfct, enum ip_conntrack_info *ctinfo)
++{
++	struct ip_conntrack *ct
++		= (struct ip_conntrack *)nfct->master;
++
++	/* ctinfo is the index of the nfct inside the conntrack */
++	*ctinfo = nfct - ct->infos;
++	IP_NF_ASSERT(*ctinfo >= 0 && *ctinfo < IP_CT_NUMBER);
++	return ct;
++}
++
++/* Return conntrack and conntrack_info given skb->nfct->master */
++struct ip_conntrack *
++ip_conntrack_get(struct sk_buff *skb, enum ip_conntrack_info *ctinfo)
++{
++	if (skb->nfct) 
++		return __ip_conntrack_get(skb->nfct, ctinfo);
++	return NULL;
++}
++
++/* Confirm a connection given skb->nfct; places it in hash table */
++int
++__ip_conntrack_confirm(struct nf_ct_info *nfct)
++{
++	unsigned int hash, repl_hash;
++	struct ip_conntrack *ct;
++	enum ip_conntrack_info ctinfo;
++
++	ct = __ip_conntrack_get(nfct, &ctinfo);
++
++	/* ipt_REJECT uses ip_conntrack_attach to attach related
++	   ICMP/TCP RST packets in other direction.  Actual packet
++	   which created connection will be IP_CT_NEW or for an
++	   expected connection, IP_CT_RELATED. */
++	if (CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL)
++		return NF_ACCEPT;
++
++	hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
++	repl_hash = hash_conntrack(&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
++
++	/* We're not in hash table, and we refuse to set up related
++	   connections for unconfirmed conns.  But packet copies and
++	   REJECT will give spurious warnings here. */
++	/* IP_NF_ASSERT(atomic_read(&ct->ct_general.use) == 1); */
++
++	/* No external references means noone else could have
++           confirmed us. */
++	IP_NF_ASSERT(!is_confirmed(ct));
++	DEBUGP("Confirming conntrack %p\n", ct);
++
++	WRITE_LOCK(&ip_conntrack_lock);
++	/* See if there's one in the list already, including reverse:
++           NAT could have grabbed it without realizing, since we're
++           not in the hash.  If there is, we lost race. */
++	if (!LIST_FIND(&ip_conntrack_hash[hash],
++		       conntrack_tuple_cmp,
++		       struct ip_conntrack_tuple_hash *,
++		       &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple, NULL)
++	    && !LIST_FIND(&ip_conntrack_hash[repl_hash],
++			  conntrack_tuple_cmp,
++			  struct ip_conntrack_tuple_hash *,
++			  &ct->tuplehash[IP_CT_DIR_REPLY].tuple, NULL)) {
++		list_prepend(&ip_conntrack_hash[hash],
++			     &ct->tuplehash[IP_CT_DIR_ORIGINAL]);
++		list_prepend(&ip_conntrack_hash[repl_hash],
++			     &ct->tuplehash[IP_CT_DIR_REPLY]);
++		/* Timer relative to confirmation time, not original
++		   setting time, otherwise we'd get timer wrap in
++		   weird delay cases. */
++		ct->timeout.expires += jiffies;
++		add_timer(&ct->timeout);
++		atomic_inc(&ct->ct_general.use);
++		set_bit(IPS_CONFIRMED_BIT, &ct->status);
++		WRITE_UNLOCK(&ip_conntrack_lock);
++		return NF_ACCEPT;
++	}
++
++	WRITE_UNLOCK(&ip_conntrack_lock);
++	return NF_DROP;
++}
++
++/* Returns true if a connection correspondings to the tuple (required
++   for NAT). */
++int
++ip_conntrack_tuple_taken(const struct ip_conntrack_tuple *tuple,
++			 const struct ip_conntrack *ignored_conntrack)
++{
++	struct ip_conntrack_tuple_hash *h;
++
++	READ_LOCK(&ip_conntrack_lock);
++	h = __ip_conntrack_find(tuple, ignored_conntrack);
++	READ_UNLOCK(&ip_conntrack_lock);
++
++	return h != NULL;
++}
++
++/* Returns conntrack if it dealt with ICMP, and filled in skb fields */
++struct ip_conntrack *
++icmp_error_track(struct sk_buff *skb,
++		 enum ip_conntrack_info *ctinfo,
++		 unsigned int hooknum)
++{
++	const struct iphdr *iph = skb->nh.iph;
++	struct icmphdr *hdr;
++	struct ip_conntrack_tuple innertuple, origtuple;
++	struct iphdr *inner;
++	size_t datalen;
++	struct ip_conntrack_protocol *innerproto;
++	struct ip_conntrack_tuple_hash *h;
++
++	IP_NF_ASSERT(iph->protocol == IPPROTO_ICMP);
++	IP_NF_ASSERT(skb->nfct == NULL);
++
++	hdr = (struct icmphdr *)((u_int32_t *)iph + iph->ihl);
++	inner = (struct iphdr *)(hdr + 1);
++	datalen = skb->len - iph->ihl*4 - sizeof(*hdr);
++
++	if (skb->len < iph->ihl * 4 + sizeof(*hdr) + sizeof(*iph)) {
++		DEBUGP("icmp_error_track: too short\n");
++		return NULL;
++	}
++
++	if (hdr->type != ICMP_DEST_UNREACH
++	    && hdr->type != ICMP_SOURCE_QUENCH
++	    && hdr->type != ICMP_TIME_EXCEEDED
++	    && hdr->type != ICMP_PARAMETERPROB
++	    && hdr->type != ICMP_REDIRECT)
++		return NULL;
++
++	/* Ignore ICMP's containing fragments (shouldn't happen) */
++	if (inner->frag_off & htons(IP_OFFSET)) {
++		DEBUGP("icmp_error_track: fragment of proto %u\n",
++		       inner->protocol);
++		return NULL;
++	}
++
++	/* Ignore it if the checksum's bogus. */
++	if (ip_compute_csum((unsigned char *)hdr, sizeof(*hdr) + datalen)) {
++		DEBUGP("icmp_error_track: bad csum\n");
++		return NULL;
++	}
++
++	innerproto = ip_ct_find_proto(inner->protocol);
++	/* Are they talking about one of our connections? */
++	if (inner->ihl * 4 + 8 > datalen
++	    || !get_tuple(inner, datalen, &origtuple, innerproto)) {
++		DEBUGP("icmp_error: ! get_tuple p=%u (%u*4+%u dlen=%u)\n",
++		       inner->protocol, inner->ihl, 8,
++		       datalen);
++		return NULL;
++	}
++
++	/* Ordinarily, we'd expect the inverted tupleproto, but it's
++	   been preserved inside the ICMP. */
++	if (!invert_tuple(&innertuple, &origtuple, innerproto)) {
++		DEBUGP("icmp_error_track: Can't invert tuple\n");
++		return NULL;
++	}
++
++	*ctinfo = IP_CT_RELATED;
++
++	h = ip_conntrack_find_get(&innertuple, NULL);
++	if (!h) {
++		/* Locally generated ICMPs will match inverted if they
++		   haven't been SNAT'ed yet */
++		/* FIXME: NAT code has to handle half-done double NAT --RR */
++		if (hooknum == NF_IP_LOCAL_OUT)
++			h = ip_conntrack_find_get(&origtuple, NULL);
++
++		if (!h) {
++			DEBUGP("icmp_error_track: no match\n");
++			return NULL;
++		}
++		/* Reverse direction from that found */
++		if (DIRECTION(h) != IP_CT_DIR_REPLY)
++			*ctinfo += IP_CT_IS_REPLY;
++	} else {
++		if (DIRECTION(h) == IP_CT_DIR_REPLY)
++			*ctinfo += IP_CT_IS_REPLY;
++	}
++
++	/* Update skb to refer to this connection */
++	skb->nfct = &h->ctrack->infos[*ctinfo];
++	return h->ctrack;
++}
++
++/* There's a small race here where we may free a just-assured
++   connection.  Too bad: we're in trouble anyway. */
++static inline int unreplied(const struct ip_conntrack_tuple_hash *i)
++{
++	return !(test_bit(IPS_ASSURED_BIT, &i->ctrack->status));
++}
++
++static int early_drop(struct list_head *chain)
++{
++	/* Traverse backwards: gives us oldest, which is roughly LRU */
++	struct ip_conntrack_tuple_hash *h;
++	int dropped = 0;
++
++	READ_LOCK(&ip_conntrack_lock);
++	h = LIST_FIND_B(chain, unreplied, struct ip_conntrack_tuple_hash *);
++	if (h)
++		atomic_inc(&h->ctrack->ct_general.use);
++	READ_UNLOCK(&ip_conntrack_lock);
++
++	if (!h)
++		return dropped;
++
++	if (del_timer(&h->ctrack->timeout)) {
++		death_by_timeout((unsigned long)h->ctrack);
++		dropped = 1;
++	}
++	ip_conntrack_put(h->ctrack);
++	return dropped;
++}
++
++static inline int helper_cmp(const struct ip_conntrack_helper *i,
++			     const struct ip_conntrack_tuple *rtuple)
++{
++	return ip_ct_tuple_mask_cmp(rtuple, &i->tuple, &i->mask);
++}
++
++struct ip_conntrack_helper *ip_ct_find_helper(const struct ip_conntrack_tuple *tuple)
++{
++	return LIST_FIND(&helpers, helper_cmp,
++			 struct ip_conntrack_helper *,
++			 tuple);
++}
++
++/* Allocate a new conntrack: we return -ENOMEM if classification
++   failed due to stress.  Otherwise it really is unclassifiable. */
++static struct ip_conntrack_tuple_hash *
++init_conntrack(const struct ip_conntrack_tuple *tuple,
++	       struct ip_conntrack_protocol *protocol,
++	       struct sk_buff *skb)
++{
++	struct ip_conntrack *conntrack;
++	struct ip_conntrack_tuple repl_tuple;
++	size_t hash;
++	struct ip_conntrack_expect *expected;
++	int i;
++	static unsigned int drop_next = 0;
++
++	if (!ip_conntrack_hash_rnd_initted) {
++		get_random_bytes(&ip_conntrack_hash_rnd, 4);
++		ip_conntrack_hash_rnd_initted = 1;
++	}
++
++	hash = hash_conntrack(tuple);
++
++	if (ip_conntrack_max &&
++	    atomic_read(&ip_conntrack_count) >= ip_conntrack_max) {
++		/* Try dropping from random chain, or else from the
++                   chain about to put into (in case they're trying to
++                   bomb one hash chain). */
++		unsigned int next = (drop_next++)%ip_conntrack_htable_size;
++
++		if (!early_drop(&ip_conntrack_hash[next])
++		    && !early_drop(&ip_conntrack_hash[hash])) {
++			if (net_ratelimit())
++				printk(KERN_WARNING
++				       "ip_conntrack: table full, dropping"
++				       " packet.\n");
++			return ERR_PTR(-ENOMEM);
++		}
++	}
++
++	if (!invert_tuple(&repl_tuple, tuple, protocol)) {
++		DEBUGP("Can't invert tuple.\n");
++		return NULL;
++	}
++
++	conntrack = kmem_cache_alloc(ip_conntrack_cachep, GFP_ATOMIC);
++	if (!conntrack) {
++		DEBUGP("Can't allocate conntrack.\n");
++		return ERR_PTR(-ENOMEM);
++	}
++
++	memset(conntrack, 0, sizeof(*conntrack));
++	atomic_set(&conntrack->ct_general.use, 1);
++	conntrack->ct_general.destroy = destroy_conntrack;
++	conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple = *tuple;
++	conntrack->tuplehash[IP_CT_DIR_ORIGINAL].ctrack = conntrack;
++	conntrack->tuplehash[IP_CT_DIR_REPLY].tuple = repl_tuple;
++	conntrack->tuplehash[IP_CT_DIR_REPLY].ctrack = conntrack;
++	for (i=0; i < IP_CT_NUMBER; i++)
++		conntrack->infos[i].master = &conntrack->ct_general;
++
++	if (!protocol->new(conntrack, skb->nh.iph, skb->len)) {
++		kmem_cache_free(ip_conntrack_cachep, conntrack);
++		return NULL;
++	}
++	/* Don't set timer yet: wait for confirmation */
++	init_timer(&conntrack->timeout);
++	conntrack->timeout.data = (unsigned long)conntrack;
++	conntrack->timeout.function = death_by_timeout;
++
++	INIT_LIST_HEAD(&conntrack->sibling_list);
++
++	WRITE_LOCK(&ip_conntrack_lock);
++	/* Need finding and deleting of expected ONLY if we win race */
++	READ_LOCK(&ip_conntrack_expect_tuple_lock);
++	expected = LIST_FIND(&ip_conntrack_expect_list, expect_cmp,
++			     struct ip_conntrack_expect *, tuple);
++	READ_UNLOCK(&ip_conntrack_expect_tuple_lock);
++
++	/* If master is not in hash table yet (ie. packet hasn't left
++	   this machine yet), how can other end know about expected?
++	   Hence these are not the droids you are looking for (if
++	   master ct never got confirmed, we'd hold a reference to it
++	   and weird things would happen to future packets). */
++	if (expected && !is_confirmed(expected->expectant))
++		expected = NULL;
++
++	/* Look up the conntrack helper for master connections only */
++	if (!expected)
++		conntrack->helper = ip_ct_find_helper(&repl_tuple);
++
++	/* If the expectation is dying, then this is a looser. */
++	if (expected
++	    && expected->expectant->helper->timeout
++	    && ! del_timer(&expected->timeout))
++		expected = NULL;
++
++	if (expected) {
++		DEBUGP("conntrack: expectation arrives ct=%p exp=%p\n",
++			conntrack, expected);
++		/* Welcome, Mr. Bond.  We've been expecting you... */
++		__set_bit(IPS_EXPECTED_BIT, &conntrack->status);
++		conntrack->master = expected;
++		expected->sibling = conntrack;
++		LIST_DELETE(&ip_conntrack_expect_list, expected);
++		expected->expectant->expecting--;
++		nf_conntrack_get(&master_ct(conntrack)->infos[0]);
++	}
++	atomic_inc(&ip_conntrack_count);
++	WRITE_UNLOCK(&ip_conntrack_lock);
++
++	if (expected && expected->expectfn)
++		expected->expectfn(conntrack);
++	return &conntrack->tuplehash[IP_CT_DIR_ORIGINAL];
++}
++
++/* On success, returns conntrack ptr, sets skb->nfct and ctinfo */
++static inline struct ip_conntrack *
++resolve_normal_ct(struct sk_buff *skb,
++		  struct ip_conntrack_protocol *proto,
++		  int *set_reply,
++		  unsigned int hooknum,
++		  enum ip_conntrack_info *ctinfo)
++{
++	struct ip_conntrack_tuple tuple;
++	struct ip_conntrack_tuple_hash *h;
++
++	IP_NF_ASSERT((skb->nh.iph->frag_off & htons(IP_OFFSET)) == 0);
++
++	if (!get_tuple(skb->nh.iph, skb->len, &tuple, proto))
++		return NULL;
++
++	/* look for tuple match */
++	h = ip_conntrack_find_get(&tuple, NULL);
++	if (!h) {
++		h = init_conntrack(&tuple, proto, skb);
++		if (!h)
++			return NULL;
++		if (IS_ERR(h))
++			return (void *)h;
++	}
++
++	/* It exists; we have (non-exclusive) reference. */
++	if (DIRECTION(h) == IP_CT_DIR_REPLY) {
++		*ctinfo = IP_CT_ESTABLISHED + IP_CT_IS_REPLY;
++		/* Please set reply bit if this packet OK */
++		*set_reply = 1;
++	} else {
++		/* Once we've had two way comms, always ESTABLISHED. */
++		if (test_bit(IPS_SEEN_REPLY_BIT, &h->ctrack->status)) {
++			DEBUGP("ip_conntrack_in: normal packet for %p\n",
++			       h->ctrack);
++		        *ctinfo = IP_CT_ESTABLISHED;
++		} else if (test_bit(IPS_EXPECTED_BIT, &h->ctrack->status)) {
++			DEBUGP("ip_conntrack_in: related packet for %p\n",
++			       h->ctrack);
++			*ctinfo = IP_CT_RELATED;
++		} else {
++			DEBUGP("ip_conntrack_in: new packet for %p\n",
++			       h->ctrack);
++			*ctinfo = IP_CT_NEW;
++		}
++		*set_reply = 0;
++	}
++	skb->nfct = &h->ctrack->infos[*ctinfo];
++	return h->ctrack;
++}
++
++/* Netfilter hook itself. */
++unsigned int ip_conntrack_in(unsigned int hooknum,
++			     struct sk_buff **pskb,
++			     const struct net_device *in,
++			     const struct net_device *out,
++			     int (*okfn)(struct sk_buff *))
++{
++	struct ip_conntrack *ct;
++	enum ip_conntrack_info ctinfo;
++	struct ip_conntrack_protocol *proto;
++	int set_reply;
++	int ret;
++
++	/* FIXME: Do this right please. --RR */
++	(*pskb)->nfcache |= NFC_UNKNOWN;
++
++/* Doesn't cover locally-generated broadcast, so not worth it. */
++#if 0
++	/* Ignore broadcast: no `connection'. */
++	if ((*pskb)->pkt_type == PACKET_BROADCAST) {
++		printk("Broadcast packet!\n");
++		return NF_ACCEPT;
++	} else if (((*pskb)->nh.iph->daddr & htonl(0x000000FF)) 
++		   == htonl(0x000000FF)) {
++		printk("Should bcast: %u.%u.%u.%u->%u.%u.%u.%u (sk=%p, ptype=%u)\n",
++		       NIPQUAD((*pskb)->nh.iph->saddr),
++		       NIPQUAD((*pskb)->nh.iph->daddr),
++		       (*pskb)->sk, (*pskb)->pkt_type);
++	}
++#endif
++
++	/* Previously seen (loopback)?  Ignore.  Do this before
++           fragment check. */
++	if ((*pskb)->nfct)
++		return NF_ACCEPT;
++
++	/* Gather fragments. */
++	if ((*pskb)->nh.iph->frag_off & htons(IP_MF|IP_OFFSET)) {
++		*pskb = ip_ct_gather_frags(*pskb);
++		if (!*pskb)
++			return NF_STOLEN;
++	}
++
++	proto = ip_ct_find_proto((*pskb)->nh.iph->protocol);
++
++	/* It may be an icmp error... */
++	if ((*pskb)->nh.iph->protocol == IPPROTO_ICMP 
++	    && icmp_error_track(*pskb, &ctinfo, hooknum))
++		return NF_ACCEPT;
++
++	if (!(ct = resolve_normal_ct(*pskb, proto,&set_reply,hooknum,&ctinfo)))
++		/* Not valid part of a connection */
++		return NF_ACCEPT;
++
++	if (IS_ERR(ct))
++		/* Too stressed to deal. */
++		return NF_DROP;
++
++	IP_NF_ASSERT((*pskb)->nfct);
++
++	ret = proto->packet(ct, (*pskb)->nh.iph, (*pskb)->len, ctinfo);
++	if (ret == -1) {
++		/* Invalid */
++		nf_conntrack_put((*pskb)->nfct);
++		(*pskb)->nfct = NULL;
++		return NF_ACCEPT;
++	}
++
++	if (ret != NF_DROP && ct->helper) {
++		ret = ct->helper->help((*pskb)->nh.iph, (*pskb)->len,
++				       ct, ctinfo);
++		if (ret == -1) {
++			/* Invalid */
++			nf_conntrack_put((*pskb)->nfct);
++			(*pskb)->nfct = NULL;
++			return NF_ACCEPT;
++		}
++	}
++	if (set_reply)
++		set_bit(IPS_SEEN_REPLY_BIT, &ct->status);
++
++	return ret;
++}
++
++int invert_tuplepr(struct ip_conntrack_tuple *inverse,
++		   const struct ip_conntrack_tuple *orig)
++{
++	return invert_tuple(inverse, orig, ip_ct_find_proto(orig->dst.protonum));
++}
++
++static inline int resent_expect(const struct ip_conntrack_expect *i,
++			        const struct ip_conntrack_tuple *tuple,
++			        const struct ip_conntrack_tuple *mask)
++{
++	DEBUGP("resent_expect\n");
++	DEBUGP("   tuple:   "); DUMP_TUPLE(&i->tuple);
++	DEBUGP("ct_tuple:   "); DUMP_TUPLE(&i->ct_tuple);
++	DEBUGP("test tuple: "); DUMP_TUPLE(tuple);
++	return (((i->ct_tuple.dst.protonum == 0 && ip_ct_tuple_equal(&i->tuple, tuple))
++	         || (i->ct_tuple.dst.protonum && ip_ct_tuple_equal(&i->ct_tuple, tuple)))
++		&& ip_ct_tuple_equal(&i->mask, mask));
++}
++
++/* Would two expected things clash? */
++static inline int expect_clash(const struct ip_conntrack_expect *i,
++			       const struct ip_conntrack_tuple *tuple,
++			       const struct ip_conntrack_tuple *mask)
++{
++	/* Part covered by intersection of masks must be unequal,
++           otherwise they clash */
++	struct ip_conntrack_tuple intersect_mask
++		= { { i->mask.src.ip & mask->src.ip,
++		      { i->mask.src.u.all & mask->src.u.all } },
++		    { i->mask.dst.ip & mask->dst.ip,
++		      { i->mask.dst.u.all & mask->dst.u.all },
++		      i->mask.dst.protonum & mask->dst.protonum } };
++
++	return ip_ct_tuple_mask_cmp(&i->tuple, tuple, &intersect_mask);
++}
++
++inline void ip_conntrack_unexpect_related(struct ip_conntrack_expect *expect)
++{
++	WRITE_LOCK(&ip_conntrack_lock);
++	unexpect_related(expect);
++	WRITE_UNLOCK(&ip_conntrack_lock);
++}
++	
++static void expectation_timed_out(unsigned long ul_expect)
++{
++	struct ip_conntrack_expect *expect = (void *) ul_expect;
++
++	DEBUGP("expectation %p timed out\n", expect);	
++	WRITE_LOCK(&ip_conntrack_lock);
++	__unexpect_related(expect);
++	WRITE_UNLOCK(&ip_conntrack_lock);
++}
++
++/* Add a related connection. */
++int ip_conntrack_expect_related(struct ip_conntrack *related_to,
++				struct ip_conntrack_expect *expect)
++{
++	struct ip_conntrack_expect *old, *new;
++	int ret = 0;
++
++	WRITE_LOCK(&ip_conntrack_lock);
++	/* Because of the write lock, no reader can walk the lists,
++	 * so there is no need to use the tuple lock too */
++
++	DEBUGP("ip_conntrack_expect_related %p\n", related_to);
++	DEBUGP("tuple: "); DUMP_TUPLE(&expect->tuple);
++	DEBUGP("mask:  "); DUMP_TUPLE(&expect->mask);
++
++	old = LIST_FIND(&ip_conntrack_expect_list, resent_expect,
++		        struct ip_conntrack_expect *, &expect->tuple, 
++			&expect->mask);
++	if (old) {
++		/* Helper private data may contain offsets but no pointers
++		   pointing into the payload - otherwise we should have to copy 
++		   the data filled out by the helper over the old one */
++		DEBUGP("expect_related: resent packet\n");
++		if (related_to->helper->timeout) {
++			if (!del_timer(&old->timeout)) {
++				/* expectation is dying. Fall through */
++				old = NULL;
++			} else {
++				old->timeout.expires = jiffies + 
++					related_to->helper->timeout * HZ;
++				add_timer(&old->timeout);
++			}
++		}
++
++		if (old) {
++			WRITE_UNLOCK(&ip_conntrack_lock);
++			return -EEXIST;
++		}
++	} else if (related_to->helper->max_expected && 
++		   related_to->expecting >= related_to->helper->max_expected) {
++		/* old == NULL */
++		if (!(related_to->helper->flags & 
++		      IP_CT_HELPER_F_REUSE_EXPECT)) {
++			WRITE_UNLOCK(&ip_conntrack_lock);
++ 		    	if (net_ratelimit())
++ 			    	printk(KERN_WARNING
++				       "ip_conntrack: max number of expected "
++				       "connections %i of %s reached for "
++				       "%u.%u.%u.%u->%u.%u.%u.%u\n",
++				       related_to->helper->max_expected,
++				       related_to->helper->name,
++ 		    	       	       NIPQUAD(related_to->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip),
++ 		    	       	       NIPQUAD(related_to->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.ip));
++			return -EPERM;
++		}
++		DEBUGP("ip_conntrack: max number of expected "
++		       "connections %i of %s reached for "
++		       "%u.%u.%u.%u->%u.%u.%u.%u, reusing\n",
++ 		       related_to->helper->max_expected,
++		       related_to->helper->name,
++		       NIPQUAD(related_to->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip),
++		       NIPQUAD(related_to->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.ip));
++ 
++		/* choose the the oldest expectation to evict */
++		list_for_each_entry(old, &related_to->sibling_list, 
++		                                      expected_list)
++			if (old->sibling == NULL)
++				break;
++
++		/* We cannot fail since related_to->expecting is the number
++		 * of unconfirmed expectations */
++		IP_NF_ASSERT(old && old->sibling == NULL);
++
++		/* newnat14 does not reuse the real allocated memory
++		 * structures but rather unexpects the old and
++		 * allocates a new.  unexpect_related will decrement
++		 * related_to->expecting. 
++		 */
++		unexpect_related(old);
++		ret = -EPERM;
++	} else if (LIST_FIND(&ip_conntrack_expect_list, expect_clash,
++			     struct ip_conntrack_expect *, &expect->tuple, 
++			     &expect->mask)) {
++		WRITE_UNLOCK(&ip_conntrack_lock);
++		DEBUGP("expect_related: busy!\n");
++		return -EBUSY;
++	}
++	
++	new = (struct ip_conntrack_expect *) 
++	      kmalloc(sizeof(struct ip_conntrack_expect), GFP_ATOMIC);
++	if (!new) {
++		WRITE_UNLOCK(&ip_conntrack_lock);
++		DEBUGP("expect_relaed: OOM allocating expect\n");
++		return -ENOMEM;
++	}
++	
++	DEBUGP("new expectation %p of conntrack %p\n", new, related_to);
++	memcpy(new, expect, sizeof(*expect));
++	new->expectant = related_to;
++	new->sibling = NULL;
++	atomic_set(&new->use, 1);
++	
++	/* add to expected list for this connection */	
++	list_add_tail(&new->expected_list, &related_to->sibling_list);
++	/* add to global list of expectations */
++	list_prepend(&ip_conntrack_expect_list, &new->list);
++	/* add and start timer if required */
++	if (related_to->helper->timeout) {
++		init_timer(&new->timeout);
++		new->timeout.data = (unsigned long)new;
++		new->timeout.function = expectation_timed_out;
++		new->timeout.expires = jiffies + 
++					related_to->helper->timeout * HZ;
++		add_timer(&new->timeout);
++	}
++	related_to->expecting++;
++
++	WRITE_UNLOCK(&ip_conntrack_lock);
++
++	return ret;
++}
++
++/* Change tuple in an existing expectation */
++int ip_conntrack_change_expect(struct ip_conntrack_expect *expect,
++			       struct ip_conntrack_tuple *newtuple)
++{
++	int ret;
++
++	MUST_BE_READ_LOCKED(&ip_conntrack_lock);
++	WRITE_LOCK(&ip_conntrack_expect_tuple_lock);
++
++	DEBUGP("change_expect:\n");
++	DEBUGP("exp tuple: "); DUMP_TUPLE(&expect->tuple);
++	DEBUGP("exp mask:  "); DUMP_TUPLE(&expect->mask);
++	DEBUGP("newtuple:  "); DUMP_TUPLE(newtuple);
++	if (expect->ct_tuple.dst.protonum == 0) {
++		/* Never seen before */
++		DEBUGP("change expect: never seen before\n");
++		if (!ip_ct_tuple_equal(&expect->tuple, newtuple) 
++		    && LIST_FIND(&ip_conntrack_expect_list, expect_clash,
++			         struct ip_conntrack_expect *, newtuple, &expect->mask)) {
++			/* Force NAT to find an unused tuple */
++			ret = -1;
++		} else {
++			memcpy(&expect->ct_tuple, &expect->tuple, sizeof(expect->tuple));
++			memcpy(&expect->tuple, newtuple, sizeof(expect->tuple));
++			ret = 0;
++		}
++	} else {
++		/* Resent packet */
++		DEBUGP("change expect: resent packet\n");
++		if (ip_ct_tuple_equal(&expect->tuple, newtuple)) {
++			ret = 0;
++		} else {
++			/* Force NAT to choose again the same port */
++			ret = -1;
++		}
++	}
++	WRITE_UNLOCK(&ip_conntrack_expect_tuple_lock);
++	
++	return ret;
++}
++
++/* Alter reply tuple (maybe alter helper).  If it's already taken,
++   return 0 and don't do alteration. */
++int ip_conntrack_alter_reply(struct ip_conntrack *conntrack,
++			     const struct ip_conntrack_tuple *newreply)
++{
++	WRITE_LOCK(&ip_conntrack_lock);
++	if (__ip_conntrack_find(newreply, conntrack)) {
++		WRITE_UNLOCK(&ip_conntrack_lock);
++		return 0;
++	}
++	/* Should be unconfirmed, so not in hash table yet */
++	IP_NF_ASSERT(!is_confirmed(conntrack));
++
++	DEBUGP("Altering reply tuple of %p to ", conntrack);
++	DUMP_TUPLE(newreply);
++
++	conntrack->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply;
++	if (!conntrack->master && list_empty(&conntrack->sibling_list))
++		conntrack->helper = ip_ct_find_helper(newreply);
++	WRITE_UNLOCK(&ip_conntrack_lock);
++
++	return 1;
++}
++
++int ip_conntrack_helper_register(struct ip_conntrack_helper *me)
++{
++	MOD_INC_USE_COUNT;
++
++	WRITE_LOCK(&ip_conntrack_lock);
++	list_prepend(&helpers, me);
++	WRITE_UNLOCK(&ip_conntrack_lock);
++
++	return 0;
++}
++
++static inline int unhelp(struct ip_conntrack_tuple_hash *i,
++			 const struct ip_conntrack_helper *me)
++{
++	if (i->ctrack->helper == me) {
++		/* Get rid of any expected. */
++		remove_expectations(i->ctrack, 0);
++		/* And *then* set helper to NULL */
++		i->ctrack->helper = NULL;
++	}
++	return 0;
++}
++
++void ip_conntrack_helper_unregister(struct ip_conntrack_helper *me)
++{
++	unsigned int i;
++
++	/* Need write lock here, to delete helper. */
++	WRITE_LOCK(&ip_conntrack_lock);
++	LIST_DELETE(&helpers, me);
++
++	/* Get rid of expecteds, set helpers to NULL. */
++	for (i = 0; i < ip_conntrack_htable_size; i++)
++		LIST_FIND_W(&ip_conntrack_hash[i], unhelp,
++			    struct ip_conntrack_tuple_hash *, me);
++	WRITE_UNLOCK(&ip_conntrack_lock);
++
++	/* Someone could be still looking at the helper in a bh. */
++	br_write_lock_bh(BR_NETPROTO_LOCK);
++	br_write_unlock_bh(BR_NETPROTO_LOCK);
++
++	MOD_DEC_USE_COUNT;
++}
++
++/* Refresh conntrack for this many jiffies. */
++void ip_ct_refresh(struct ip_conntrack *ct, unsigned long extra_jiffies)
++{
++	IP_NF_ASSERT(ct->timeout.data == (unsigned long)ct);
++
++	WRITE_LOCK(&ip_conntrack_lock);
++	/* If not in hash table, timer will not be active yet */
++	if (!is_confirmed(ct))
++		ct->timeout.expires = extra_jiffies;
++	else {
++		/* Need del_timer for race avoidance (may already be dying). */
++		if (del_timer(&ct->timeout)) {
++			ct->timeout.expires = jiffies + extra_jiffies;
++			add_timer(&ct->timeout);
++		}
++	}
++	WRITE_UNLOCK(&ip_conntrack_lock);
++}
++
++/* Returns new sk_buff, or NULL */
++struct sk_buff *
++ip_ct_gather_frags(struct sk_buff *skb)
++{
++	struct sock *sk = skb->sk;
++#ifdef CONFIG_NETFILTER_DEBUG
++	unsigned int olddebug = skb->nf_debug;
++#endif
++	if (sk) {
++		sock_hold(sk);
++		skb_orphan(skb);
++	}
++
++	local_bh_disable(); 
++	skb = ip_defrag(skb);
++	local_bh_enable();
++
++	if (!skb) {
++		if (sk) sock_put(sk);
++		return skb;
++	} else if (skb_is_nonlinear(skb) && skb_linearize(skb, GFP_ATOMIC) != 0) {
++		kfree_skb(skb);
++		if (sk) sock_put(sk);
++		return NULL;
++	}
++
++	if (sk) {
++		skb_set_owner_w(skb, sk);
++		sock_put(sk);
++	}
++
++	ip_send_check(skb->nh.iph);
++	skb->nfcache |= NFC_ALTERED;
++#ifdef CONFIG_NETFILTER_DEBUG
++	/* Packet path as if nothing had happened. */
++	skb->nf_debug = olddebug;
++#endif
++	return skb;
++}
++
++/* Used by ipt_REJECT. */
++static void ip_conntrack_attach(struct sk_buff *nskb, struct nf_ct_info *nfct)
++{
++	struct ip_conntrack *ct;
++	enum ip_conntrack_info ctinfo;
++
++	ct = __ip_conntrack_get(nfct, &ctinfo);
++
++	/* This ICMP is in reverse direction to the packet which
++           caused it */
++	if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL)
++		ctinfo = IP_CT_RELATED + IP_CT_IS_REPLY;
++	else
++		ctinfo = IP_CT_RELATED;
++
++	/* Attach new skbuff, and increment count */
++	nskb->nfct = &ct->infos[ctinfo];
++	atomic_inc(&ct->ct_general.use);
++}
++
++static inline int
++do_kill(const struct ip_conntrack_tuple_hash *i,
++	int (*kill)(const struct ip_conntrack *i, void *data),
++	void *data)
++{
++	return kill(i->ctrack, data);
++}
++
++/* Bring out ya dead! */
++static struct ip_conntrack_tuple_hash *
++get_next_corpse(int (*kill)(const struct ip_conntrack *i, void *data),
++		void *data, unsigned int *bucket)
++{
++	struct ip_conntrack_tuple_hash *h = NULL;
++
++	READ_LOCK(&ip_conntrack_lock);
++	for (; !h && *bucket < ip_conntrack_htable_size; (*bucket)++) {
++		h = LIST_FIND(&ip_conntrack_hash[*bucket], do_kill,
++			      struct ip_conntrack_tuple_hash *, kill, data);
++	}
++	if (h)
++		atomic_inc(&h->ctrack->ct_general.use);
++	READ_UNLOCK(&ip_conntrack_lock);
++
++	return h;
++}
++
++void
++ip_ct_selective_cleanup(int (*kill)(const struct ip_conntrack *i, void *data),
++			void *data)
++{
++	struct ip_conntrack_tuple_hash *h;
++	unsigned int bucket = 0;
++
++	while ((h = get_next_corpse(kill, data, &bucket)) != NULL) {
++		/* Time to push up daises... */
++		if (del_timer(&h->ctrack->timeout))
++			death_by_timeout((unsigned long)h->ctrack);
++		/* ... else the timer will get him soon. */
++
++		ip_conntrack_put(h->ctrack);
++	}
++}
++
++/* Fast function for those who don't want to parse /proc (and I don't
++   blame them). */
++/* Reversing the socket's dst/src point of view gives us the reply
++   mapping. */
++static int
++getorigdst(struct sock *sk, int optval, void *user, int *len)
++{
++	struct ip_conntrack_tuple_hash *h;
++	struct ip_conntrack_tuple tuple;
++
++	IP_CT_TUPLE_U_BLANK(&tuple);
++	tuple.src.ip = sk->rcv_saddr;
++	tuple.src.u.tcp.port = sk->sport;
++	tuple.dst.ip = sk->daddr;
++	tuple.dst.u.tcp.port = sk->dport;
++	tuple.dst.protonum = IPPROTO_TCP;
++
++	/* We only do TCP at the moment: is there a better way? */
++	if (strcmp(sk->prot->name, "TCP") != 0) {
++		DEBUGP("SO_ORIGINAL_DST: Not a TCP socket\n");
++		return -ENOPROTOOPT;
++	}
++
++	if ((unsigned int) *len < sizeof(struct sockaddr_in)) {
++		DEBUGP("SO_ORIGINAL_DST: len %u not %u\n",
++		       *len, sizeof(struct sockaddr_in));
++		return -EINVAL;
++	}
++
++	h = ip_conntrack_find_get(&tuple, NULL);
++	if (h) {
++		struct sockaddr_in sin;
++
++		sin.sin_family = AF_INET;
++		sin.sin_port = h->ctrack->tuplehash[IP_CT_DIR_ORIGINAL]
++			.tuple.dst.u.tcp.port;
++		sin.sin_addr.s_addr = h->ctrack->tuplehash[IP_CT_DIR_ORIGINAL]
++			.tuple.dst.ip;
++
++		DEBUGP("SO_ORIGINAL_DST: %u.%u.%u.%u %u\n",
++		       NIPQUAD(sin.sin_addr.s_addr), ntohs(sin.sin_port));
++		ip_conntrack_put(h->ctrack);
++		if (copy_to_user(user, &sin, sizeof(sin)) != 0)
++			return -EFAULT;
++		else
++			return 0;
++	}
++	DEBUGP("SO_ORIGINAL_DST: Can't find %u.%u.%u.%u/%u-%u.%u.%u.%u/%u.\n",
++	       NIPQUAD(tuple.src.ip), ntohs(tuple.src.u.tcp.port),
++	       NIPQUAD(tuple.dst.ip), ntohs(tuple.dst.u.tcp.port));
++	return -ENOENT;
++}
++
++static struct nf_sockopt_ops so_getorigdst
++= { { NULL, NULL }, PF_INET,
++    0, 0, NULL, /* Setsockopts */
++    SO_ORIGINAL_DST, SO_ORIGINAL_DST+1, &getorigdst,
++    0, NULL };
++
++static int kill_all(const struct ip_conntrack *i, void *data)
++{
++	return 1;
++}
++
++/* Mishearing the voices in his head, our hero wonders how he's
++   supposed to kill the mall. */
++void ip_conntrack_cleanup(void)
++{
++	ip_ct_attach = NULL;
++	/* This makes sure all current packets have passed through
++           netfilter framework.  Roll on, two-stage module
++           delete... */
++	br_write_lock_bh(BR_NETPROTO_LOCK);
++	br_write_unlock_bh(BR_NETPROTO_LOCK);
++ 
++ i_see_dead_people:
++	ip_ct_selective_cleanup(kill_all, NULL);
++	if (atomic_read(&ip_conntrack_count) != 0) {
++		schedule();
++		goto i_see_dead_people;
++	}
++
++	kmem_cache_destroy(ip_conntrack_cachep);
++	vfree(ip_conntrack_hash);
++	nf_unregister_sockopt(&so_getorigdst);
++}
++
++static int hashsize = 0;
++MODULE_PARM(hashsize, "i");
++
++int __init ip_conntrack_init(void)
++{
++	unsigned int i;
++	int ret;
++
++	/* Idea from tcp.c: use 1/16384 of memory.  On i386: 32MB
++	 * machine has 256 buckets.  >= 1GB machines have 8192 buckets. */
++ 	if (hashsize) {
++ 		ip_conntrack_htable_size = hashsize;
++ 	} else {
++		ip_conntrack_htable_size
++			= (((num_physpages << PAGE_SHIFT) / 16384)
++			   / sizeof(struct list_head));
++		if (num_physpages > (1024 * 1024 * 1024 / PAGE_SIZE))
++			ip_conntrack_htable_size = 8192;
++		if (ip_conntrack_htable_size < 16)
++			ip_conntrack_htable_size = 16;
++	}
++	ip_conntrack_max = 8 * ip_conntrack_htable_size;
++
++	printk("ip_conntrack version %s (%u buckets, %d max)"
++	       " - %Zd bytes per conntrack\n", IP_CONNTRACK_VERSION,
++	       ip_conntrack_htable_size, ip_conntrack_max,
++	       sizeof(struct ip_conntrack));
++
++	ret = nf_register_sockopt(&so_getorigdst);
++	if (ret != 0) {
++		printk(KERN_ERR "Unable to register netfilter socket option\n");
++		return ret;
++	}
++
++	ip_conntrack_hash = vmalloc(sizeof(struct list_head)
++				    * ip_conntrack_htable_size);
++	if (!ip_conntrack_hash) {
++		printk(KERN_ERR "Unable to create ip_conntrack_hash\n");
++		goto err_unreg_sockopt;
++	}
++
++	ip_conntrack_cachep = kmem_cache_create("ip_conntrack",
++	                                        sizeof(struct ip_conntrack), 0,
++	                                        SLAB_HWCACHE_ALIGN, NULL, NULL);
++	if (!ip_conntrack_cachep) {
++		printk(KERN_ERR "Unable to create ip_conntrack slab cache\n");
++		goto err_free_hash;
++	}
++	/* Don't NEED lock here, but good form anyway. */
++	WRITE_LOCK(&ip_conntrack_lock);
++	/* Sew in builtin protocols. */
++	list_append(&protocol_list, &ip_conntrack_protocol_tcp);
++	list_append(&protocol_list, &ip_conntrack_protocol_udp);
++	list_append(&protocol_list, &ip_conntrack_protocol_icmp);
++	WRITE_UNLOCK(&ip_conntrack_lock);
++
++	for (i = 0; i < ip_conntrack_htable_size; i++)
++		INIT_LIST_HEAD(&ip_conntrack_hash[i]);
++
++	/* For use by ipt_REJECT */
++	ip_ct_attach = ip_conntrack_attach;
++	return ret;
++
++err_free_hash:
++	vfree(ip_conntrack_hash);
++err_unreg_sockopt:
++	nf_unregister_sockopt(&so_getorigdst);
++
++	return -ENOMEM;
++}
+diff -uNr linux_org/net/ipv4/netfilter/ip_conntrack_pptp.c linux/net/ipv4/netfilter/ip_conntrack_pptp.c
+--- linux_org/net/ipv4/netfilter/ip_conntrack_pptp.c	1970-01-01 01:00:00.000000000 +0100
++++ linux/net/ipv4/netfilter/ip_conntrack_pptp.c	2006-10-27 14:11:52.000000000 +0200
+@@ -0,0 +1,637 @@
++/*
++ * ip_conntrack_pptp.c	- Version 1.9
++ *
++ * Connection tracking support for PPTP (Point to Point Tunneling Protocol).
++ * PPTP is a a protocol for creating virtual private networks.
++ * It is a specification defined by Microsoft and some vendors
++ * working with Microsoft.  PPTP is built on top of a modified
++ * version of the Internet Generic Routing Encapsulation Protocol.
++ * GRE is defined in RFC 1701 and RFC 1702.  Documentation of
++ * PPTP can be found in RFC 2637
++ *
++ * (C) 2000-2003 by Harald Welte <laforge@gnumonks.org>
++ *
++ * Development of this code funded by Astaro AG (http://www.astaro.com/)
++ *
++ * Limitations:
++ * 	 - We blindly assume that control connections are always
++ * 	   established in PNS->PAC direction.  This is a violation
++ * 	   of RFFC2673
++ *
++ * TODO: - finish support for multiple calls within one session
++ * 	   (needs expect reservations in newnat)
++ *	 - testing of incoming PPTP calls 
++ *
++ * Changes: 
++ * 	2002-02-05 - Version 1.3
++ * 	  - Call ip_conntrack_unexpect_related() from 
++ * 	    pptp_timeout_related() to destroy expectations in case
++ * 	    CALL_DISCONNECT_NOTIFY or tcp fin packet was seen
++ * 	    (Philip Craig <philipc@snapgear.com>)
++ * 	  - Add Version information at module loadtime
++ * 	2002-02-10 - Version 1.6
++ * 	  - move to C99 style initializers
++ * 	  - remove second expectation if first arrives
++ *
++ */
++
++#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_proto_gre.h>
++#include <linux/netfilter_ipv4/ip_conntrack_pptp.h>
++
++#define IP_CT_PPTP_VERSION "1.9"
++
++MODULE_LICENSE("GPL");
++MODULE_AUTHOR("Harald Welte <laforge@gnumonks.org>");
++MODULE_DESCRIPTION("Netfilter connection tracking helper module for PPTP");
++
++DECLARE_LOCK(ip_pptp_lock);
++
++#if 0
++#include "ip_conntrack_pptp_priv.h"
++#define DEBUGP(format, args...)	printk(KERN_DEBUG __FILE__ ":" __FUNCTION__ \
++					": " format, ## args)
++#else
++#define DEBUGP(format, args...)
++#endif
++
++#define SECS *HZ
++#define MINS * 60 SECS
++#define HOURS * 60 MINS
++#define DAYS * 24 HOURS
++
++#define PPTP_GRE_TIMEOUT 		(10 MINS)
++#define PPTP_GRE_STREAM_TIMEOUT 	(5 DAYS)
++
++static int pptp_expectfn(struct ip_conntrack *ct)
++{
++	struct ip_conntrack *master;
++	struct ip_conntrack_expect *exp;
++
++	DEBUGP("increasing timeouts\n");
++	/* increase timeout of GRE data channel conntrack entry */
++	ct->proto.gre.timeout = PPTP_GRE_TIMEOUT;
++	ct->proto.gre.stream_timeout = PPTP_GRE_STREAM_TIMEOUT;
++
++	master = master_ct(ct);
++	if (!master) {
++		DEBUGP(" no master!!!\n");
++		return 0;
++	}
++
++	exp = ct->master;
++	if (!exp) {
++		DEBUGP("no expectation!!\n");
++		return 0;
++	}
++
++	DEBUGP("completing tuples with ct info\n");
++	/* we can do this, since we're unconfirmed */
++	if (ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.gre.key == 
++		htonl(master->help.ct_pptp_info.pac_call_id)) {	
++		/* assume PNS->PAC */
++		ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.gre.key = 
++			htonl(master->help.ct_pptp_info.pns_call_id);
++		ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u.gre.key =
++			htonl(master->help.ct_pptp_info.pns_call_id);
++	} else {
++		/* assume PAC->PNS */
++		ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.gre.key =
++			htonl(master->help.ct_pptp_info.pac_call_id);
++		ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u.gre.key =
++			htonl(master->help.ct_pptp_info.pac_call_id);
++	}
++	
++	/* delete other expectation */
++	if (exp->expected_list.next != &exp->expected_list) {
++		struct ip_conntrack_expect *other_exp;
++		struct list_head *cur_item, *next;
++
++		for (cur_item = master->sibling_list.next;
++		     cur_item != &master->sibling_list; cur_item = next) {
++			next = cur_item->next;
++			other_exp = list_entry(cur_item,
++					       struct ip_conntrack_expect,
++					       expected_list);
++			/* remove only if occurred at same sequence number */
++			if (other_exp != exp && other_exp->seq == exp->seq) {
++				DEBUGP("unexpecting other direction\n");
++				ip_ct_gre_keymap_destroy(other_exp);
++				ip_conntrack_unexpect_related(other_exp);
++			}
++		}
++	}
++
++	return 0;
++}
++
++/* timeout GRE data connections */
++static int pptp_timeout_related(struct ip_conntrack *ct)
++{
++	struct list_head *cur_item, *next;
++	struct ip_conntrack_expect *exp;
++
++	/* FIXME: do we have to lock something ? */
++	for (cur_item = ct->sibling_list.next;
++	    cur_item != &ct->sibling_list; cur_item = next) {
++		next = cur_item->next;
++		exp = list_entry(cur_item, struct ip_conntrack_expect,
++				 expected_list);
++
++		ip_ct_gre_keymap_destroy(exp);
++		if (!exp->sibling) {
++			ip_conntrack_unexpect_related(exp);
++			continue;
++		}
++
++		DEBUGP("setting timeout of conntrack %p to 0\n",
++			exp->sibling);
++		exp->sibling->proto.gre.timeout = 0;
++		exp->sibling->proto.gre.stream_timeout = 0;
++		ip_ct_refresh(exp->sibling, 0);
++	}
++
++	return 0;
++}
++
++/* expect GRE connections (PNS->PAC and PAC->PNS direction) */
++static inline int
++exp_gre(struct ip_conntrack *master,
++	u_int32_t seq,
++	u_int16_t callid,
++	u_int16_t peer_callid)
++{
++	struct ip_conntrack_expect exp;
++	struct ip_conntrack_tuple inv_tuple;
++
++	memset(&exp, 0, sizeof(exp));
++	/* tuple in original direction, PNS->PAC */
++	exp.tuple.src.ip = master->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip;
++	exp.tuple.src.u.gre.key = htonl(ntohs(peer_callid));
++	exp.tuple.dst.ip = master->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.ip;
++	exp.tuple.dst.u.gre.key = htonl(ntohs(callid));
++	exp.tuple.dst.u.gre.protocol = __constant_htons(GRE_PROTOCOL_PPTP);
++	exp.tuple.dst.u.gre.version = GRE_VERSION_PPTP;
++	exp.tuple.dst.protonum = IPPROTO_GRE;
++
++	exp.mask.src.ip = 0xffffffff;
++	exp.mask.src.u.all = 0;
++	exp.mask.dst.u.all = 0;
++	exp.mask.dst.u.gre.key = 0xffffffff;
++	exp.mask.dst.u.gre.version = 0xff;
++	exp.mask.dst.u.gre.protocol = 0xffff;
++	exp.mask.dst.ip = 0xffffffff;
++	exp.mask.dst.protonum = 0xffff;
++			
++	exp.seq = seq;
++	exp.expectfn = pptp_expectfn;
++
++	exp.help.exp_pptp_info.pac_call_id = ntohs(callid);
++	exp.help.exp_pptp_info.pns_call_id = ntohs(peer_callid);
++
++	DEBUGP("calling expect_related ");
++	DUMP_TUPLE_RAW(&exp.tuple);
++	
++	/* Add GRE keymap entries */
++	if (ip_ct_gre_keymap_add(&exp, &exp.tuple, 0) != 0)
++		return 1;
++
++	invert_tuplepr(&inv_tuple, &exp.tuple);
++	if (ip_ct_gre_keymap_add(&exp, &inv_tuple, 1) != 0) {
++		ip_ct_gre_keymap_destroy(&exp);
++		return 1;
++	}
++	
++	if (ip_conntrack_expect_related(master, &exp) != 0) {
++		ip_ct_gre_keymap_destroy(&exp);
++		DEBUGP("cannot expect_related()\n");
++		return 1;
++	}
++
++	/* tuple in reply direction, PAC->PNS */
++	exp.tuple.src.ip = master->tuplehash[IP_CT_DIR_REPLY].tuple.src.ip;
++	exp.tuple.src.u.gre.key = htonl(ntohs(callid));
++	exp.tuple.dst.ip = master->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip;
++	exp.tuple.dst.u.gre.key = htonl(ntohs(peer_callid));
++
++	DEBUGP("calling expect_related ");
++	DUMP_TUPLE_RAW(&exp.tuple);
++	
++	/* Add GRE keymap entries */
++	ip_ct_gre_keymap_add(&exp, &exp.tuple, 0);
++	invert_tuplepr(&inv_tuple, &exp.tuple);
++	ip_ct_gre_keymap_add(&exp, &inv_tuple, 1);
++	/* FIXME: cannot handle error correctly, since we need to free
++	 * the above keymap :( */
++	
++	if (ip_conntrack_expect_related(master, &exp) != 0) {
++		/* free the second pair of keypmaps */
++		ip_ct_gre_keymap_destroy(&exp);
++		DEBUGP("cannot expect_related():\n");
++		return 1;
++	}
++
++	return 0;
++}
++
++static inline int 
++pptp_inbound_pkt(struct tcphdr *tcph,
++		 struct pptp_pkt_hdr *pptph, 
++		 size_t datalen,
++		 struct ip_conntrack *ct,
++		 enum ip_conntrack_info ctinfo)
++{
++	struct PptpControlHeader *ctlh;
++        union pptp_ctrl_union pptpReq;
++	
++	struct ip_ct_pptp_master *info = &ct->help.ct_pptp_info;
++	u_int16_t msg, *cid, *pcid;
++	u_int32_t seq;	
++
++	ctlh = (struct PptpControlHeader *) 
++		((char *) pptph + sizeof(struct pptp_pkt_hdr));
++	pptpReq.rawreq = (void *) 
++		((char *) ctlh + sizeof(struct PptpControlHeader));
++
++	msg = ntohs(ctlh->messageType);
++	DEBUGP("inbound control message %s\n", strMName[msg]);
++
++	switch (msg) {
++	case PPTP_START_SESSION_REPLY:
++		/* server confirms new control session */
++		if (info->sstate < PPTP_SESSION_REQUESTED) {
++			DEBUGP("%s without START_SESS_REQUEST\n",
++				strMName[msg]);
++			break;
++		}
++		if (pptpReq.srep->resultCode == PPTP_START_OK)
++			info->sstate = PPTP_SESSION_CONFIRMED;
++		else 
++			info->sstate = PPTP_SESSION_ERROR;
++		break;
++
++	case PPTP_STOP_SESSION_REPLY:
++		/* server confirms end of control session */
++		if (info->sstate > PPTP_SESSION_STOPREQ) {
++			DEBUGP("%s without STOP_SESS_REQUEST\n",
++				strMName[msg]);
++			break;
++		}
++		if (pptpReq.strep->resultCode == PPTP_STOP_OK)
++			info->sstate = PPTP_SESSION_NONE;
++		else
++			info->sstate = PPTP_SESSION_ERROR;
++		break;
++
++	case PPTP_OUT_CALL_REPLY:
++		/* server accepted call, we now expect GRE frames */
++		if (info->sstate != PPTP_SESSION_CONFIRMED) {
++			DEBUGP("%s but no session\n", strMName[msg]);
++			break;
++		}
++		if (info->cstate != PPTP_CALL_OUT_REQ &&
++		    info->cstate != PPTP_CALL_OUT_CONF) {
++			DEBUGP("%s without OUTCALL_REQ\n", strMName[msg]);
++			break;
++		}
++		if (pptpReq.ocack->resultCode != PPTP_OUTCALL_CONNECT) {
++			info->cstate = PPTP_CALL_NONE;
++			break;
++		}
++
++		cid = &pptpReq.ocack->callID;
++		pcid = &pptpReq.ocack->peersCallID;
++
++		info->pac_call_id = ntohs(*cid);
++		
++		if (htons(info->pns_call_id) != *pcid) {
++			DEBUGP("%s for unknown callid %u\n",
++				strMName[msg], ntohs(*pcid));
++			break;
++		}
++
++		DEBUGP("%s, CID=%X, PCID=%X\n", strMName[msg], 
++			ntohs(*cid), ntohs(*pcid));
++		
++		info->cstate = PPTP_CALL_OUT_CONF;
++
++		seq = ntohl(tcph->seq) + ((void *)pcid - (void *)pptph);
++		if (exp_gre(ct, seq, *cid, *pcid) != 0)
++			printk("ip_conntrack_pptp: error during exp_gre\n");
++		break;
++
++	case PPTP_IN_CALL_REQUEST:
++		/* server tells us about incoming call request */
++		if (info->sstate != PPTP_SESSION_CONFIRMED) {
++			DEBUGP("%s but no session\n", strMName[msg]);
++			break;
++		}
++		pcid = &pptpReq.icack->peersCallID;
++		DEBUGP("%s, PCID=%X\n", strMName[msg], ntohs(*pcid));
++		info->cstate = PPTP_CALL_IN_REQ;
++		info->pac_call_id= ntohs(*pcid);
++		break;
++
++	case PPTP_IN_CALL_CONNECT:
++		/* server tells us about incoming call established */
++		if (info->sstate != PPTP_SESSION_CONFIRMED) {
++			DEBUGP("%s but no session\n", strMName[msg]);
++			break;
++		}
++		if (info->sstate != PPTP_CALL_IN_REP
++		    && info->sstate != PPTP_CALL_IN_CONF) {
++			DEBUGP("%s but never sent IN_CALL_REPLY\n",
++				strMName[msg]);
++			break;
++		}
++
++		pcid = &pptpReq.iccon->peersCallID;
++		cid = &info->pac_call_id;
++
++		if (info->pns_call_id != ntohs(*pcid)) {
++			DEBUGP("%s for unknown CallID %u\n", 
++				strMName[msg], ntohs(*cid));
++			break;
++		}
++
++		DEBUGP("%s, PCID=%X\n", strMName[msg], ntohs(*pcid));
++		info->cstate = PPTP_CALL_IN_CONF;
++
++		/* we expect a GRE connection from PAC to PNS */
++		seq = ntohl(tcph->seq) + ((void *)pcid - (void *)pptph);
++		if (exp_gre(ct, seq, *cid, *pcid) != 0)
++			printk("ip_conntrack_pptp: error during exp_gre\n");
++
++		break;
++
++	case PPTP_CALL_DISCONNECT_NOTIFY:
++		/* server confirms disconnect */
++		cid = &pptpReq.disc->callID;
++		DEBUGP("%s, CID=%X\n", strMName[msg], ntohs(*cid));
++		info->cstate = PPTP_CALL_NONE;
++
++		/* untrack this call id, unexpect GRE packets */
++		pptp_timeout_related(ct);
++		break;
++
++	case PPTP_WAN_ERROR_NOTIFY:
++		break;
++
++	case PPTP_ECHO_REQUEST:
++	case PPTP_ECHO_REPLY:
++		/* I don't have to explain these ;) */
++		break;
++	default:
++		DEBUGP("invalid %s (TY=%d)\n", (msg <= PPTP_MSG_MAX)
++			? strMName[msg]:strMName[0], msg);
++		break;
++	}
++
++	return NF_ACCEPT;
++
++}
++
++static inline int
++pptp_outbound_pkt(struct tcphdr *tcph,
++		  struct pptp_pkt_hdr *pptph,
++		  size_t datalen,
++		  struct ip_conntrack *ct,
++		  enum ip_conntrack_info ctinfo)
++{
++	struct PptpControlHeader *ctlh;
++        union pptp_ctrl_union pptpReq;
++	struct ip_ct_pptp_master *info = &ct->help.ct_pptp_info;
++	u_int16_t msg, *cid, *pcid;
++
++	ctlh = (struct PptpControlHeader *) ((void *) pptph + sizeof(*pptph));
++	pptpReq.rawreq = (void *) ((void *) ctlh + sizeof(*ctlh));
++
++	msg = ntohs(ctlh->messageType);
++	DEBUGP("outbound control message %s\n", strMName[msg]);
++
++	switch (msg) {
++	case PPTP_START_SESSION_REQUEST:
++		/* client requests for new control session */
++		if (info->sstate != PPTP_SESSION_NONE) {
++			DEBUGP("%s but we already have one",
++				strMName[msg]);
++		}
++		info->sstate = PPTP_SESSION_REQUESTED;
++		break;
++	case PPTP_STOP_SESSION_REQUEST:
++		/* client requests end of control session */
++		info->sstate = PPTP_SESSION_STOPREQ;
++		break;
++
++	case PPTP_OUT_CALL_REQUEST:
++		/* client initiating connection to server */
++		if (info->sstate != PPTP_SESSION_CONFIRMED) {
++			DEBUGP("%s but no session\n",
++				strMName[msg]);
++			break;
++		}
++		info->cstate = PPTP_CALL_OUT_REQ;
++		/* track PNS call id */
++		cid = &pptpReq.ocreq->callID;
++		DEBUGP("%s, CID=%X\n", strMName[msg], ntohs(*cid));
++		info->pns_call_id = ntohs(*cid);
++		break;
++	case PPTP_IN_CALL_REPLY:
++		/* client answers incoming call */
++		if (info->cstate != PPTP_CALL_IN_REQ
++		    && info->cstate != PPTP_CALL_IN_REP) {
++			DEBUGP("%s without incall_req\n", 
++				strMName[msg]);
++			break;
++		}
++		if (pptpReq.icack->resultCode != PPTP_INCALL_ACCEPT) {
++			info->cstate = PPTP_CALL_NONE;
++			break;
++		}
++		pcid = &pptpReq.icack->peersCallID;
++		if (info->pac_call_id != ntohs(*pcid)) {
++			DEBUGP("%s for unknown call %u\n", 
++				strMName[msg], ntohs(*pcid));
++			break;
++		}
++		DEBUGP("%s, CID=%X\n", strMName[msg], ntohs(*pcid));
++		/* part two of the three-way handshake */
++		info->cstate = PPTP_CALL_IN_REP;
++		info->pns_call_id = ntohs(pptpReq.icack->callID);
++		break;
++
++	case PPTP_CALL_CLEAR_REQUEST:
++		/* client requests hangup of call */
++		if (info->sstate != PPTP_SESSION_CONFIRMED) {
++			DEBUGP("CLEAR_CALL but no session\n");
++			break;
++		}
++		/* FUTURE: iterate over all calls and check if
++		 * call ID is valid.  We don't do this without newnat,
++		 * because we only know about last call */
++		info->cstate = PPTP_CALL_CLEAR_REQ;
++		break;
++	case PPTP_SET_LINK_INFO:
++		break;
++	case PPTP_ECHO_REQUEST:
++	case PPTP_ECHO_REPLY:
++		/* I don't have to explain these ;) */
++		break;
++	default:
++		DEBUGP("invalid %s (TY=%d)\n", (msg <= PPTP_MSG_MAX)? 
++			strMName[msg]:strMName[0], msg);
++		/* unknown: no need to create GRE masq table entry */
++		break;
++	}
++
++	return NF_ACCEPT;
++}
++
++
++/* track caller id inside control connection, call expect_related */
++static int 
++conntrack_pptp_help(const struct iphdr *iph, size_t len,
++		    struct ip_conntrack *ct, enum ip_conntrack_info ctinfo)
++
++{
++	struct pptp_pkt_hdr *pptph;
++	
++	struct tcphdr *tcph = (void *) iph + iph->ihl * 4;
++	u_int32_t tcplen = len - iph->ihl * 4;
++	u_int32_t datalen = tcplen - tcph->doff * 4;
++	void *datalimit;
++	int dir = CTINFO2DIR(ctinfo);
++	struct ip_ct_pptp_master *info = &ct->help.ct_pptp_info;
++
++	int oldsstate, oldcstate;
++	int ret;
++
++	/* don't do any tracking before tcp handshake complete */
++	if (ctinfo != IP_CT_ESTABLISHED 
++	    && ctinfo != IP_CT_ESTABLISHED+IP_CT_IS_REPLY) {
++		DEBUGP("ctinfo = %u, skipping\n", ctinfo);
++		return NF_ACCEPT;
++	}
++	
++	/* not a complete TCP header? */
++	if (tcplen < sizeof(struct tcphdr) || tcplen < tcph->doff * 4) {
++		DEBUGP("tcplen = %u\n", tcplen);
++		return NF_ACCEPT;
++	}
++
++	/* checksum invalid? */
++	if (tcp_v4_check(tcph, tcplen, iph->saddr, iph->daddr,
++			csum_partial((char *) tcph, tcplen, 0))) {
++		printk(KERN_NOTICE __FILE__ ": bad csum\n");
++		/* W2K PPTP server sends TCP packets with wrong checksum :(( */
++		//return NF_ACCEPT;
++	}
++
++	if (tcph->fin || tcph->rst) {
++		DEBUGP("RST/FIN received, timeouting GRE\n");
++		/* can't do this after real newnat */
++		info->cstate = PPTP_CALL_NONE;
++
++		/* untrack this call id, unexpect GRE packets */
++		pptp_timeout_related(ct);
++	}
++
++
++	pptph = (struct pptp_pkt_hdr *) ((void *) tcph + tcph->doff * 4);
++	datalimit = (void *) pptph + datalen;
++
++	/* not a full pptp packet header? */
++	if ((void *) pptph+sizeof(*pptph) >= datalimit) {
++		DEBUGP("no full PPTP header, can't track\n");
++		return NF_ACCEPT;
++	}
++	
++	/* if it's not a control message we can't do anything with it */
++        if (ntohs(pptph->packetType) != PPTP_PACKET_CONTROL ||
++	    ntohl(pptph->magicCookie) != PPTP_MAGIC_COOKIE) {
++		DEBUGP("not a control packet\n");
++		return NF_ACCEPT;
++	}
++
++	oldsstate = info->sstate;
++	oldcstate = info->cstate;
++
++	LOCK_BH(&ip_pptp_lock);
++
++	/* FIXME: We just blindly assume that the control connection is always
++	 * established from PNS->PAC.  However, RFC makes no guarantee */
++	if (dir == IP_CT_DIR_ORIGINAL)
++		/* client -> server (PNS -> PAC) */
++		ret = pptp_outbound_pkt(tcph, pptph, datalen, ct, ctinfo);
++	else
++		/* server -> client (PAC -> PNS) */
++		ret = pptp_inbound_pkt(tcph, pptph, datalen, ct, ctinfo);
++	DEBUGP("sstate: %d->%d, cstate: %d->%d\n",
++		oldsstate, info->sstate, oldcstate, info->cstate);
++	UNLOCK_BH(&ip_pptp_lock);
++
++	return ret;
++}
++
++/* control protocol helper */
++static struct ip_conntrack_helper pptp = { 
++	.list = { NULL, NULL },
++	.name = "pptp", 
++	.flags = IP_CT_HELPER_F_REUSE_EXPECT,
++	.me = THIS_MODULE,
++	.max_expected = 2,
++	.timeout = 0,
++	.tuple = { .src = { .ip = 0, 
++		 	    .u = { .tcp = { .port =  
++				    __constant_htons(PPTP_CONTROL_PORT) } } 
++			  }, 
++		   .dst = { .ip = 0, 
++			    .u = { .all = 0 },
++			    .protonum = IPPROTO_TCP
++			  } 
++		 },
++	.mask = { .src = { .ip = 0, 
++			   .u = { .tcp = { .port = 0xffff } } 
++			 }, 
++		  .dst = { .ip = 0, 
++			   .u = { .all = 0 },
++			   .protonum = 0xffff 
++		 	 } 
++		},
++	.help = conntrack_pptp_help
++};
++
++/* ip_conntrack_pptp initialization */
++static int __init init(void)
++{
++	int retcode;
++
++	DEBUGP(__FILE__ ": registering helper\n");
++	if ((retcode = ip_conntrack_helper_register(&pptp))) {
++                printk(KERN_ERR "Unable to register conntrack application "
++				"helper for pptp: %d\n", retcode);
++		return -EIO;
++	}
++
++	printk("ip_conntrack_pptp version %s loaded\n", IP_CT_PPTP_VERSION);
++	return 0;
++}
++
++static void __exit fini(void)
++{
++	ip_conntrack_helper_unregister(&pptp);
++	printk("ip_conntrack_pptp version %s unloaded\n", IP_CT_PPTP_VERSION);
++}
++
++module_init(init);
++module_exit(fini);
++
++EXPORT_SYMBOL(ip_pptp_lock);
+diff -uNr linux_org/net/ipv4/netfilter/ip_conntrack_pptp_priv.h linux/net/ipv4/netfilter/ip_conntrack_pptp_priv.h
+--- linux_org/net/ipv4/netfilter/ip_conntrack_pptp_priv.h	1970-01-01 01:00:00.000000000 +0100
++++ linux/net/ipv4/netfilter/ip_conntrack_pptp_priv.h	2006-10-27 14:11:52.000000000 +0200
+@@ -0,0 +1,24 @@
++#ifndef _IP_CT_PPTP_PRIV_H
++#define _IP_CT_PPTP_PRIV_H
++
++/* PptpControlMessageType names */
++static const char *strMName[] = {
++	"UNKNOWN_MESSAGE",
++	"START_SESSION_REQUEST",
++	"START_SESSION_REPLY",
++	"STOP_SESSION_REQUEST",
++	"STOP_SESSION_REPLY",
++	"ECHO_REQUEST",
++	"ECHO_REPLY",
++	"OUT_CALL_REQUEST",
++	"OUT_CALL_REPLY",
++	"IN_CALL_REQUEST",
++	"IN_CALL_REPLY",
++	"IN_CALL_CONNECT",
++	"CALL_CLEAR_REQUEST",
++	"CALL_DISCONNECT_NOTIFY",
++	"WAN_ERROR_NOTIFY",
++	"SET_LINK_INFO"
++};
++
++#endif
+diff -uNr linux_org/net/ipv4/netfilter/ip_conntrack_proto_gre.c linux/net/ipv4/netfilter/ip_conntrack_proto_gre.c
+--- linux_org/net/ipv4/netfilter/ip_conntrack_proto_gre.c	1970-01-01 01:00:00.000000000 +0100
++++ linux/net/ipv4/netfilter/ip_conntrack_proto_gre.c	2006-10-27 14:11:52.000000000 +0200
+@@ -0,0 +1,343 @@
++/*
++ * ip_conntrack_proto_gre.c - Version 1.2 
++ *
++ * Connection tracking protocol helper module for GRE.
++ *
++ * GRE is a generic encapsulation protocol, which is generally not very
++ * suited for NAT, as it has no protocol-specific part as port numbers.
++ *
++ * It has an optional key field, which may help us distinguishing two 
++ * connections between the same two hosts.
++ *
++ * GRE is defined in RFC 1701 and RFC 1702, as well as RFC 2784 
++ *
++ * PPTP is built on top of a modified version of GRE, and has a mandatory
++ * field called "CallID", which serves us for the same purpose as the key
++ * field in plain GRE.
++ *
++ * Documentation about PPTP can be found in RFC 2637
++ *
++ * (C) 2000-2003 by Harald Welte <laforge@gnumonks.org>
++ *
++ * Development of this code funded by Astaro AG (http://www.astaro.com/)
++ *
++ */
++
++#include <linux/config.h>
++#include <linux/module.h>
++#include <linux/types.h>
++#include <linux/timer.h>
++#include <linux/netfilter.h>
++#include <linux/ip.h>
++#include <linux/in.h>
++#include <linux/list.h>
++
++#include <linux/netfilter_ipv4/lockhelp.h>
++
++DECLARE_RWLOCK(ip_ct_gre_lock);
++#define ASSERT_READ_LOCK(x) MUST_BE_READ_LOCKED(&ip_ct_gre_lock)
++#define ASSERT_WRITE_LOCK(x) MUST_BE_WRITE_LOCKED(&ip_ct_gre_lock)
++
++#include <linux/netfilter_ipv4/listhelp.h>
++#include <linux/netfilter_ipv4/ip_conntrack_protocol.h>
++#include <linux/netfilter_ipv4/ip_conntrack_helper.h>
++#include <linux/netfilter_ipv4/ip_conntrack_core.h>
++
++#include <linux/netfilter_ipv4/ip_conntrack_proto_gre.h>
++#include <linux/netfilter_ipv4/ip_conntrack_pptp.h>
++
++MODULE_LICENSE("GPL");
++MODULE_AUTHOR("Harald Welte <laforge@gnumonks.org>");
++MODULE_DESCRIPTION("netfilter connection tracking protocol helper for GRE");
++
++/* shamelessly stolen from ip_conntrack_proto_udp.c */
++#define GRE_TIMEOUT		(30*HZ)
++#define GRE_STREAM_TIMEOUT	(180*HZ)
++
++#if 0
++#define DEBUGP(format, args...) printk(KERN_DEBUG __FILE__ ":" __FUNCTION__ \
++		                       ": " format, ## args)
++#define DUMP_TUPLE_GRE(x) printk("%u.%u.%u.%u:0x%x -> %u.%u.%u.%u:0x%x:%u:0x%x\n", \
++			NIPQUAD((x)->src.ip), ntohl((x)->src.u.gre.key), \
++			NIPQUAD((x)->dst.ip), ntohl((x)->dst.u.gre.key), \
++			(x)->dst.u.gre.version, \
++			ntohs((x)->dst.u.gre.protocol))
++#else
++#define DEBUGP(x, args...)
++#define DUMP_TUPLE_GRE(x)
++#endif
++				
++/* GRE KEYMAP HANDLING FUNCTIONS */
++static LIST_HEAD(gre_keymap_list);
++
++static inline int gre_key_cmpfn(const struct ip_ct_gre_keymap *km,
++				const struct ip_conntrack_tuple *t)
++{
++	return ((km->tuple.src.ip == t->src.ip) &&
++		(km->tuple.dst.ip == t->dst.ip) &&
++	        (km->tuple.dst.protonum == t->dst.protonum) &&
++	        (km->tuple.dst.u.all == t->dst.u.all));
++}
++
++/* look up the source key for a given tuple */
++static u_int32_t gre_keymap_lookup(struct ip_conntrack_tuple *t)
++{
++	struct ip_ct_gre_keymap *km;
++	u_int32_t key;
++
++	READ_LOCK(&ip_ct_gre_lock);
++	km = LIST_FIND(&gre_keymap_list, gre_key_cmpfn,
++			struct ip_ct_gre_keymap *, t);
++	if (!km) {
++		READ_UNLOCK(&ip_ct_gre_lock);
++		return 0;
++	}
++
++	key = km->tuple.src.u.gre.key;
++	READ_UNLOCK(&ip_ct_gre_lock);
++
++	return key;
++}
++
++/* add a single keymap entry, associate with specified expect */
++int ip_ct_gre_keymap_add(struct ip_conntrack_expect *exp,
++			 struct ip_conntrack_tuple *t, int reply)
++{
++	struct ip_ct_gre_keymap *km;
++
++	km = kmalloc(sizeof(*km), GFP_ATOMIC);
++	if (!km)
++		return -1;
++
++	/* initializing list head should be sufficient */
++	memset(km, 0, sizeof(*km));
++
++	memcpy(&km->tuple, t, sizeof(*t));
++
++	if (!reply)
++		exp->proto.gre.keymap_orig = km;
++	else
++		exp->proto.gre.keymap_reply = km;
++
++	DEBUGP("adding new entry %p: ", km);
++	DUMP_TUPLE_GRE(&km->tuple);
++
++	WRITE_LOCK(&ip_ct_gre_lock);
++	list_append(&gre_keymap_list, km);
++	WRITE_UNLOCK(&ip_ct_gre_lock);
++
++	return 0;
++}
++
++/* change the tuple of a keymap entry (used by nat helper) */
++void ip_ct_gre_keymap_change(struct ip_ct_gre_keymap *km,
++			     struct ip_conntrack_tuple *t)
++{
++	DEBUGP("changing entry %p to: ", km);
++	DUMP_TUPLE_GRE(t);
++
++	WRITE_LOCK(&ip_ct_gre_lock);
++	memcpy(&km->tuple, t, sizeof(km->tuple));
++	WRITE_UNLOCK(&ip_ct_gre_lock);
++}
++
++/* destroy the keymap entries associated with specified expect */
++void ip_ct_gre_keymap_destroy(struct ip_conntrack_expect *exp)
++{
++	DEBUGP("entering for exp %p\n", exp);
++	WRITE_LOCK(&ip_ct_gre_lock);
++	if (exp->proto.gre.keymap_orig) {
++		DEBUGP("removing %p from list\n", exp->proto.gre.keymap_orig);
++		list_del(&exp->proto.gre.keymap_orig->list);
++		kfree(exp->proto.gre.keymap_orig);
++		exp->proto.gre.keymap_orig = NULL;
++	}
++	if (exp->proto.gre.keymap_reply) {
++		DEBUGP("removing %p from list\n", exp->proto.gre.keymap_reply);
++		list_del(&exp->proto.gre.keymap_reply->list);
++		kfree(exp->proto.gre.keymap_reply);
++		exp->proto.gre.keymap_reply = NULL;
++	}
++	WRITE_UNLOCK(&ip_ct_gre_lock);
++}
++
++
++/* PUBLIC CONNTRACK PROTO HELPER FUNCTIONS */
++
++/* invert gre part of tuple */
++static int gre_invert_tuple(struct ip_conntrack_tuple *tuple,
++			    const struct ip_conntrack_tuple *orig)
++{
++	tuple->dst.u.gre.protocol = orig->dst.u.gre.protocol;
++	tuple->dst.u.gre.version = orig->dst.u.gre.version;
++
++	tuple->dst.u.gre.key = orig->src.u.gre.key;
++	tuple->src.u.gre.key = orig->dst.u.gre.key;
++
++	return 1;
++}
++
++/* gre hdr info to tuple */
++static int gre_pkt_to_tuple(const void *datah, size_t datalen,
++			    struct ip_conntrack_tuple *tuple)
++{
++	struct gre_hdr *grehdr = (struct gre_hdr *) datah;
++	struct gre_hdr_pptp *pgrehdr = (struct gre_hdr_pptp *) datah;
++	u_int32_t srckey;
++
++	/* core guarantees 8 protocol bytes, no need for size check */
++
++	tuple->dst.u.gre.version = grehdr->version; 
++	tuple->dst.u.gre.protocol = grehdr->protocol;
++
++	switch (grehdr->version) {
++		case GRE_VERSION_1701:
++			if (!grehdr->key) {
++				DEBUGP("Can't track GRE without key\n");
++				return 0;
++			}
++			tuple->dst.u.gre.key = *(gre_key(grehdr));
++			break;
++
++		case GRE_VERSION_PPTP:
++			if (ntohs(grehdr->protocol) != GRE_PROTOCOL_PPTP) {
++				DEBUGP("GRE_VERSION_PPTP but unknown proto\n");
++				return 0;
++			}
++			tuple->dst.u.gre.key = htonl(ntohs(pgrehdr->call_id));
++			break;
++
++		default:
++			printk(KERN_WARNING "unknown GRE version %hu\n",
++				tuple->dst.u.gre.version);
++			return 0;
++	}
++
++	srckey = gre_keymap_lookup(tuple);
++
++#if 0
++	DEBUGP("found src key %x for tuple ", ntohl(srckey));
++	DUMP_TUPLE_GRE(tuple);
++#endif
++	tuple->src.u.gre.key = srckey;
++
++	return 1;
++}
++
++/* print gre part of tuple */
++static unsigned int gre_print_tuple(char *buffer,
++				    const struct ip_conntrack_tuple *tuple)
++{
++	return sprintf(buffer, "version=%d protocol=0x%04x srckey=0x%x dstkey=0x%x ", 
++			tuple->dst.u.gre.version,
++			ntohs(tuple->dst.u.gre.protocol),
++			ntohl(tuple->src.u.gre.key),
++			ntohl(tuple->dst.u.gre.key));
++}
++
++/* print private data for conntrack */
++static unsigned int gre_print_conntrack(char *buffer,
++					const struct ip_conntrack *ct)
++{
++	return sprintf(buffer, "timeout=%u, stream_timeout=%u ",
++		       (ct->proto.gre.timeout / HZ),
++		       (ct->proto.gre.stream_timeout / HZ));
++}
++
++/* Returns verdict for packet, and may modify conntrack */
++static int gre_packet(struct ip_conntrack *ct,
++		      struct iphdr *iph, size_t len,
++		      enum ip_conntrack_info conntrackinfo)
++{
++	/* If we've seen traffic both ways, this is a GRE connection.
++	 * Extend timeout. */
++	if (ct->status & IPS_SEEN_REPLY) {
++		ip_ct_refresh(ct, ct->proto.gre.stream_timeout);
++		/* Also, more likely to be important, and not a probe. */
++		set_bit(IPS_ASSURED_BIT, &ct->status);
++	} else
++		ip_ct_refresh(ct, ct->proto.gre.timeout);
++	
++	return NF_ACCEPT;
++}
++
++/* Called when a new connection for this protocol found. */
++static int gre_new(struct ip_conntrack *ct,
++		   struct iphdr *iph, size_t len)
++{ 
++	DEBUGP(": ");
++	DUMP_TUPLE_GRE(&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
++
++	/* initialize to sane value.  Ideally a conntrack helper
++	 * (e.g. in case of pptp) is increasing them */
++	ct->proto.gre.stream_timeout = GRE_STREAM_TIMEOUT;
++	ct->proto.gre.timeout = GRE_TIMEOUT;
++
++	return 1;
++}
++
++/* Called when a conntrack entry has already been removed from the hashes
++ * and is about to be deleted from memory */
++static void gre_destroy(struct ip_conntrack *ct)
++{
++	struct ip_conntrack_expect *master = ct->master;
++
++	DEBUGP(" entering\n");
++
++	if (!master) {
++		DEBUGP("no master exp for ct %p\n", ct);
++		return;
++	}
++
++	ip_ct_gre_keymap_destroy(master);
++}
++
++/* protocol helper struct */
++static struct ip_conntrack_protocol gre = { { NULL, NULL }, IPPROTO_GRE,
++					    "gre", 
++					    gre_pkt_to_tuple,
++					    gre_invert_tuple,
++					    gre_print_tuple,
++					    gre_print_conntrack,
++					    gre_packet,
++					    gre_new,
++					    gre_destroy,
++					    NULL,
++					    THIS_MODULE };
++
++/* ip_conntrack_proto_gre initialization */
++static int __init init(void)
++{
++	int retcode;
++
++	if ((retcode = ip_conntrack_protocol_register(&gre))) {
++                printk(KERN_ERR "Unable to register conntrack protocol "
++			        "helper for gre: %d\n",	retcode);
++		return -EIO;
++	}
++
++	return 0;
++}
++
++static void __exit fini(void)
++{
++	struct list_head *pos, *n;
++
++	/* delete all keymap entries */
++	WRITE_LOCK(&ip_ct_gre_lock);
++	list_for_each_safe(pos, n, &gre_keymap_list) {
++		DEBUGP("deleting keymap %p at module unload time\n", pos);
++		list_del(pos);
++		kfree(pos);
++	}
++	WRITE_UNLOCK(&ip_ct_gre_lock);
++
++	ip_conntrack_protocol_unregister(&gre); 
++}
++
++EXPORT_SYMBOL(ip_ct_gre_keymap_add);
++EXPORT_SYMBOL(ip_ct_gre_keymap_change);
++EXPORT_SYMBOL(ip_ct_gre_keymap_destroy);
++
++module_init(init);
++module_exit(fini);
+diff -uNr linux_org/net/ipv4/netfilter/ip_nat_core.c linux/net/ipv4/netfilter/ip_nat_core.c
+--- linux_org/net/ipv4/netfilter/ip_nat_core.c	2004-11-24 12:14:04.000000000 +0100
++++ linux/net/ipv4/netfilter/ip_nat_core.c	2006-10-27 14:11:52.000000000 +0200
+@@ -430,7 +430,7 @@
+ 	*tuple = *orig_tuple;
+ 	while ((rptr = find_best_ips_proto_fast(tuple, mr, conntrack, hooknum))
+ 	       != NULL) {
+-		DEBUGP("Found best for "); DUMP_TUPLE(tuple);
++		DEBUGP("Found best for "); DUMP_TUPLE_RAW(tuple);
+ 		/* 3) The per-protocol part of the manip is made to
+ 		   map into the range to make a unique tuple. */
+ 
+@@ -572,9 +572,9 @@
+ 		       HOOK2MANIP(hooknum)==IP_NAT_MANIP_SRC ? "SRC" : "DST",
+ 		       conntrack);
+ 		DEBUGP("Original: ");
+-		DUMP_TUPLE(&orig_tp);
++		DUMP_TUPLE_RAW(&orig_tp);
+ 		DEBUGP("New: ");
+-		DUMP_TUPLE(&new_tuple);
++		DUMP_TUPLE_RAW(&new_tuple);
+ #endif
+ 
+ 		/* We now have two tuples (SRCIP/SRCPT/DSTIP/DSTPT):
+diff -uNr linux_org/net/ipv4/netfilter/ip_nat_core.c.orig linux/net/ipv4/netfilter/ip_nat_core.c.orig
+--- linux_org/net/ipv4/netfilter/ip_nat_core.c.orig	1970-01-01 01:00:00.000000000 +0100
++++ linux/net/ipv4/netfilter/ip_nat_core.c.orig	2004-11-24 12:14:04.000000000 +0100
+@@ -0,0 +1,1014 @@
++/* NAT for netfilter; shared with compatibility layer. */
++
++/* (c) 1999 Paul `Rusty' Russell.  Licenced under the GNU General
++   Public Licence. */
++#include <linux/version.h>
++#include <linux/module.h>
++#include <linux/types.h>
++#include <linux/timer.h>
++#include <linux/skbuff.h>
++#include <linux/netfilter_ipv4.h>
++#include <linux/brlock.h>
++#include <linux/vmalloc.h>
++#include <net/checksum.h>
++#include <net/icmp.h>
++#include <net/ip.h>
++#include <net/tcp.h>  /* For tcp_prot in getorigdst */
++
++#define ASSERT_READ_LOCK(x) MUST_BE_READ_LOCKED(&ip_nat_lock)
++#define ASSERT_WRITE_LOCK(x) MUST_BE_WRITE_LOCKED(&ip_nat_lock)
++
++#include <linux/netfilter_ipv4/ip_conntrack.h>
++#include <linux/netfilter_ipv4/ip_conntrack_core.h>
++#include <linux/netfilter_ipv4/ip_conntrack_protocol.h>
++#include <linux/netfilter_ipv4/ip_nat.h>
++#include <linux/netfilter_ipv4/ip_nat_protocol.h>
++#include <linux/netfilter_ipv4/ip_nat_core.h>
++#include <linux/netfilter_ipv4/ip_nat_helper.h>
++#include <linux/netfilter_ipv4/ip_conntrack_helper.h>
++#include <linux/netfilter_ipv4/listhelp.h>
++
++#if 0
++#define DEBUGP printk
++#else
++#define DEBUGP(format, args...)
++#endif
++
++DECLARE_RWLOCK(ip_nat_lock);
++DECLARE_RWLOCK_EXTERN(ip_conntrack_lock);
++
++/* Calculated at init based on memory size */
++static unsigned int ip_nat_htable_size;
++
++static struct list_head *bysource;
++static struct list_head *byipsproto;
++LIST_HEAD(protos);
++LIST_HEAD(helpers);
++
++extern struct ip_nat_protocol unknown_nat_protocol;
++
++/* We keep extra hashes for each conntrack, for fast searching. */
++static inline size_t
++hash_by_ipsproto(u_int32_t src, u_int32_t dst, u_int16_t proto)
++{
++	/* Modified src and dst, to ensure we don't create two
++           identical streams. */
++	return (src + dst + proto) % ip_nat_htable_size;
++}
++
++static inline size_t
++hash_by_src(const struct ip_conntrack_manip *manip, u_int16_t proto)
++{
++	/* Original src, to ensure we map it consistently if poss. */
++	return (manip->ip + manip->u.all + proto) % ip_nat_htable_size;
++}
++
++/* Noone using conntrack by the time this called. */
++static void ip_nat_cleanup_conntrack(struct ip_conntrack *conn)
++{
++	struct ip_nat_info *info = &conn->nat.info;
++	unsigned int hs, hp;
++
++	if (!info->initialized)
++		return;
++
++	IP_NF_ASSERT(info->bysource.conntrack);
++	IP_NF_ASSERT(info->byipsproto.conntrack);
++
++	hs = hash_by_src(&conn->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src,
++	                 conn->tuplehash[IP_CT_DIR_ORIGINAL]
++	                 .tuple.dst.protonum);
++
++	hp = hash_by_ipsproto(conn->tuplehash[IP_CT_DIR_REPLY].tuple.src.ip,
++	                      conn->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip,
++	                      conn->tuplehash[IP_CT_DIR_REPLY]
++	                      .tuple.dst.protonum);
++
++	WRITE_LOCK(&ip_nat_lock);
++	LIST_DELETE(&bysource[hs], &info->bysource);
++	LIST_DELETE(&byipsproto[hp], &info->byipsproto);
++	WRITE_UNLOCK(&ip_nat_lock);
++}
++
++/* We do checksum mangling, so if they were wrong before they're still
++ * wrong.  Also works for incomplete packets (eg. ICMP dest
++ * unreachables.) */
++u_int16_t
++ip_nat_cheat_check(u_int32_t oldvalinv, u_int32_t newval, u_int16_t oldcheck)
++{
++	u_int32_t diffs[] = { oldvalinv, newval };
++	return csum_fold(csum_partial((char *)diffs, sizeof(diffs),
++				      oldcheck^0xFFFF));
++}
++
++static inline int cmp_proto(const struct ip_nat_protocol *i, int proto)
++{
++	return i->protonum == proto;
++}
++
++struct ip_nat_protocol *
++find_nat_proto(u_int16_t protonum)
++{
++	struct ip_nat_protocol *i;
++
++	MUST_BE_READ_LOCKED(&ip_nat_lock);
++	i = LIST_FIND(&protos, cmp_proto, struct ip_nat_protocol *, protonum);
++	if (!i)
++		i = &unknown_nat_protocol;
++	return i;
++}
++
++/* Is this tuple already taken? (not by us) */
++int
++ip_nat_used_tuple(const struct ip_conntrack_tuple *tuple,
++		  const struct ip_conntrack *ignored_conntrack)
++{
++	/* Conntrack tracking doesn't keep track of outgoing tuples; only
++	   incoming ones.  NAT means they don't have a fixed mapping,
++	   so we invert the tuple and look for the incoming reply.
++
++	   We could keep a separate hash if this proves too slow. */
++	struct ip_conntrack_tuple reply;
++
++	invert_tuplepr(&reply, tuple);
++	return ip_conntrack_tuple_taken(&reply, ignored_conntrack);
++}
++
++/* Does tuple + the source manip come within the range mr */
++static int
++in_range(const struct ip_conntrack_tuple *tuple,
++	 const struct ip_conntrack_manip *manip,
++	 const struct ip_nat_multi_range *mr)
++{
++	struct ip_nat_protocol *proto = find_nat_proto(tuple->dst.protonum);
++	unsigned int i;
++	struct ip_conntrack_tuple newtuple = { *manip, tuple->dst };
++
++	for (i = 0; i < mr->rangesize; i++) {
++		/* If we are allowed to map IPs, then we must be in the
++		   range specified, otherwise we must be unchanged. */
++		if (mr->range[i].flags & IP_NAT_RANGE_MAP_IPS) {
++			if (ntohl(newtuple.src.ip) < ntohl(mr->range[i].min_ip)
++			    || (ntohl(newtuple.src.ip)
++				> ntohl(mr->range[i].max_ip)))
++				continue;
++		} else {
++			if (newtuple.src.ip != tuple->src.ip)
++				continue;
++		}
++
++		if ((mr->range[i].flags & IP_NAT_RANGE_PROTO_SPECIFIED)
++		    && proto->in_range(&newtuple, IP_NAT_MANIP_SRC,
++				       &mr->range[i].min, &mr->range[i].max))
++			return 1;
++	}
++	return 0;
++}
++
++static inline int
++src_cmp(const struct ip_nat_hash *i,
++	const struct ip_conntrack_tuple *tuple,
++	const struct ip_nat_multi_range *mr)
++{
++	return (i->conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum
++		== tuple->dst.protonum
++		&& i->conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip
++		== tuple->src.ip
++		&& i->conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.all
++		== tuple->src.u.all
++		&& in_range(tuple,
++			    &i->conntrack->tuplehash[IP_CT_DIR_ORIGINAL]
++			    .tuple.src,
++			    mr));
++}
++
++/* Only called for SRC manip */
++static struct ip_conntrack_manip *
++find_appropriate_src(const struct ip_conntrack_tuple *tuple,
++		     const struct ip_nat_multi_range *mr)
++{
++	unsigned int h = hash_by_src(&tuple->src, tuple->dst.protonum);
++	struct ip_nat_hash *i;
++
++	MUST_BE_READ_LOCKED(&ip_nat_lock);
++	i = LIST_FIND(&bysource[h], src_cmp, struct ip_nat_hash *, tuple, mr);
++	if (i)
++		return &i->conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src;
++	else
++		return NULL;
++}
++
++#ifdef CONFIG_IP_NF_NAT_LOCAL
++/* If it's really a local destination manip, it may need to do a
++   source manip too. */
++static int
++do_extra_mangle(u_int32_t var_ip, u_int32_t *other_ipp)
++{
++	struct rtable *rt;
++
++	/* FIXME: IPTOS_TOS(iph->tos) --RR */
++	if (ip_route_output(&rt, var_ip, 0, 0, 0) != 0) {
++		DEBUGP("do_extra_mangle: Can't get route to %u.%u.%u.%u\n",
++		       NIPQUAD(var_ip));
++		return 0;
++	}
++
++	*other_ipp = rt->rt_src;
++	ip_rt_put(rt);
++	return 1;
++}
++#endif
++
++/* Simple way to iterate through all. */
++static inline int fake_cmp(const struct ip_nat_hash *i,
++			   u_int32_t src, u_int32_t dst, u_int16_t protonum,
++			   unsigned int *score,
++			   const struct ip_conntrack *conntrack)
++{
++	/* Compare backwards: we're dealing with OUTGOING tuples, and
++           inside the conntrack is the REPLY tuple.  Don't count this
++           conntrack. */
++	if (i->conntrack != conntrack
++	    && i->conntrack->tuplehash[IP_CT_DIR_REPLY].tuple.src.ip == dst
++	    && i->conntrack->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip == src
++	    && (i->conntrack->tuplehash[IP_CT_DIR_REPLY].tuple.dst.protonum
++		== protonum))
++		(*score)++;
++	return 0;
++}
++
++static inline unsigned int
++count_maps(u_int32_t src, u_int32_t dst, u_int16_t protonum,
++	   const struct ip_conntrack *conntrack)
++{
++	unsigned int score = 0;
++	unsigned int h;
++
++	MUST_BE_READ_LOCKED(&ip_nat_lock);
++	h = hash_by_ipsproto(src, dst, protonum);
++	LIST_FIND(&byipsproto[h], fake_cmp, struct ip_nat_hash *,
++	          src, dst, protonum, &score, conntrack);
++
++	return score;
++}
++
++/* For [FUTURE] fragmentation handling, we want the least-used
++   src-ip/dst-ip/proto triple.  Fairness doesn't come into it.  Thus
++   if the range specifies 1.2.3.4 ports 10000-10005 and 1.2.3.5 ports
++   1-65535, we don't do pro-rata allocation based on ports; we choose
++   the ip with the lowest src-ip/dst-ip/proto usage.
++
++   If an allocation then fails (eg. all 6 ports used in the 1.2.3.4
++   range), we eliminate that and try again.  This is not the most
++   efficient approach, but if you're worried about that, don't hand us
++   ranges you don't really have.  */
++static struct ip_nat_range *
++find_best_ips_proto(struct ip_conntrack_tuple *tuple,
++		    const struct ip_nat_multi_range *mr,
++		    const struct ip_conntrack *conntrack,
++		    unsigned int hooknum)
++{
++	unsigned int i;
++	struct {
++		const struct ip_nat_range *range;
++		unsigned int score;
++		struct ip_conntrack_tuple tuple;
++	} best = { NULL,  0xFFFFFFFF };
++	u_int32_t *var_ipp, *other_ipp, saved_ip, orig_dstip;
++	static unsigned int randomness = 0;
++
++	if (HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC) {
++		var_ipp = &tuple->src.ip;
++		saved_ip = tuple->dst.ip;
++		other_ipp = &tuple->dst.ip;
++	} else {
++		var_ipp = &tuple->dst.ip;
++		saved_ip = tuple->src.ip;
++		other_ipp = &tuple->src.ip;
++	}
++	/* Don't do do_extra_mangle unless neccessary (overrides
++           explicit socket bindings, for example) */
++	orig_dstip = tuple->dst.ip;
++
++	IP_NF_ASSERT(mr->rangesize >= 1);
++	for (i = 0; i < mr->rangesize; i++) {
++		/* Host order */
++		u_int32_t minip, maxip, j;
++
++		/* Don't do ranges which are already eliminated. */
++		if (mr->range[i].flags & IP_NAT_RANGE_FULL) {
++			continue;
++		}
++
++		if (mr->range[i].flags & IP_NAT_RANGE_MAP_IPS) {
++			minip = ntohl(mr->range[i].min_ip);
++			maxip = ntohl(mr->range[i].max_ip);
++		} else
++			minip = maxip = ntohl(*var_ipp);
++
++		randomness++;
++		for (j = 0; j < maxip - minip + 1; j++) {
++			unsigned int score;
++
++			*var_ipp = htonl(minip + (randomness + j) 
++					 % (maxip - minip + 1));
++
++			/* Reset the other ip in case it was mangled by
++			 * do_extra_mangle last time. */
++			*other_ipp = saved_ip;
++
++#ifdef CONFIG_IP_NF_NAT_LOCAL
++			if (hooknum == NF_IP_LOCAL_OUT
++			    && *var_ipp != orig_dstip
++			    && !do_extra_mangle(*var_ipp, other_ipp)) {
++				DEBUGP("Range %u %u.%u.%u.%u rt failed!\n",
++				       i, NIPQUAD(*var_ipp));
++				/* Can't route?  This whole range part is
++				 * probably screwed, but keep trying
++				 * anyway. */
++				continue;
++			}
++#endif
++
++			/* Count how many others map onto this. */
++			score = count_maps(tuple->src.ip, tuple->dst.ip,
++					   tuple->dst.protonum, conntrack);
++			if (score < best.score) {
++				/* Optimization: doesn't get any better than
++				   this. */
++				if (score == 0)
++					return (struct ip_nat_range *)
++						&mr->range[i];
++
++				best.score = score;
++				best.tuple = *tuple;
++				best.range = &mr->range[i];
++			}
++		}
++	}
++	*tuple = best.tuple;
++
++	/* Discard const. */
++	return (struct ip_nat_range *)best.range;
++}
++
++/* Fast version doesn't iterate through hash chains, but only handles
++   common case of single IP address (null NAT, masquerade) */
++static struct ip_nat_range *
++find_best_ips_proto_fast(struct ip_conntrack_tuple *tuple,
++			 const struct ip_nat_multi_range *mr,
++			 const struct ip_conntrack *conntrack,
++			 unsigned int hooknum)
++{
++	if (mr->rangesize != 1
++	    || (mr->range[0].flags & IP_NAT_RANGE_FULL)
++	    || ((mr->range[0].flags & IP_NAT_RANGE_MAP_IPS)
++		&& mr->range[0].min_ip != mr->range[0].max_ip))
++		return find_best_ips_proto(tuple, mr, conntrack, hooknum);
++
++	if (mr->range[0].flags & IP_NAT_RANGE_MAP_IPS) {
++		if (HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC)
++			tuple->src.ip = mr->range[0].min_ip;
++		else {
++			/* Only do extra mangle when required (breaks
++                           socket binding) */
++#ifdef CONFIG_IP_NF_NAT_LOCAL
++			if (tuple->dst.ip != mr->range[0].min_ip
++			    && hooknum == NF_IP_LOCAL_OUT
++			    && !do_extra_mangle(mr->range[0].min_ip,
++						&tuple->src.ip))
++				return NULL;
++#endif
++			tuple->dst.ip = mr->range[0].min_ip;
++		}
++	}
++
++	/* Discard const. */
++	return (struct ip_nat_range *)&mr->range[0];
++}
++
++static int
++get_unique_tuple(struct ip_conntrack_tuple *tuple,
++		 const struct ip_conntrack_tuple *orig_tuple,
++		 const struct ip_nat_multi_range *mrr,
++		 struct ip_conntrack *conntrack,
++		 unsigned int hooknum)
++{
++	struct ip_nat_protocol *proto
++		= find_nat_proto(orig_tuple->dst.protonum);
++	struct ip_nat_range *rptr;
++	unsigned int i;
++	int ret;
++
++	/* We temporarily use flags for marking full parts, but we
++	   always clean up afterwards */
++	struct ip_nat_multi_range *mr = (void *)mrr;
++
++	/* 1) If this srcip/proto/src-proto-part is currently mapped,
++	   and that same mapping gives a unique tuple within the given
++	   range, use that.
++
++	   This is only required for source (ie. NAT/masq) mappings.
++	   So far, we don't do local source mappings, so multiple
++	   manips not an issue.  */
++	if (hooknum == NF_IP_POST_ROUTING) {
++		struct ip_conntrack_manip *manip;
++
++		manip = find_appropriate_src(orig_tuple, mr);
++		if (manip) {
++			/* Apply same source manipulation. */
++			*tuple = ((struct ip_conntrack_tuple)
++				  { *manip, orig_tuple->dst });
++			DEBUGP("get_unique_tuple: Found current src map\n");
++			return 1;
++		}
++	}
++
++	/* 2) Select the least-used IP/proto combination in the given
++	   range.
++	*/
++	*tuple = *orig_tuple;
++	while ((rptr = find_best_ips_proto_fast(tuple, mr, conntrack, hooknum))
++	       != NULL) {
++		DEBUGP("Found best for "); DUMP_TUPLE(tuple);
++		/* 3) The per-protocol part of the manip is made to
++		   map into the range to make a unique tuple. */
++
++		/* Only bother mapping if it's not already in range
++		   and unique */
++		if ((!(rptr->flags & IP_NAT_RANGE_PROTO_SPECIFIED)
++		     || proto->in_range(tuple, HOOK2MANIP(hooknum),
++					&rptr->min, &rptr->max))
++		    && !ip_nat_used_tuple(tuple, conntrack)) {
++			ret = 1;
++			goto clear_fulls;
++		} else {
++			if (proto->unique_tuple(tuple, rptr,
++						HOOK2MANIP(hooknum),
++						conntrack)) {
++				/* Must be unique. */
++				IP_NF_ASSERT(!ip_nat_used_tuple(tuple,
++								conntrack));
++				ret = 1;
++				goto clear_fulls;
++			} else if (HOOK2MANIP(hooknum) == IP_NAT_MANIP_DST) {
++				/* Try implicit source NAT; protocol
++                                   may be able to play with ports to
++                                   make it unique. */
++				struct ip_nat_range r
++					= { IP_NAT_RANGE_MAP_IPS, 
++					    tuple->src.ip, tuple->src.ip,
++					    { 0 }, { 0 } };
++				DEBUGP("Trying implicit mapping\n");
++				if (proto->unique_tuple(tuple, &r,
++							IP_NAT_MANIP_SRC,
++							conntrack)) {
++					/* Must be unique. */
++					IP_NF_ASSERT(!ip_nat_used_tuple
++						     (tuple, conntrack));
++					ret = 1;
++					goto clear_fulls;
++				}
++			}
++			DEBUGP("Protocol can't get unique tuple %u.\n",
++			       hooknum);
++		}
++
++		/* Eliminate that from range, and try again. */
++		rptr->flags |= IP_NAT_RANGE_FULL;
++		*tuple = *orig_tuple;
++	}
++
++	ret = 0;
++
++ clear_fulls:
++	/* Clear full flags. */
++	IP_NF_ASSERT(mr->rangesize >= 1);
++	for (i = 0; i < mr->rangesize; i++)
++		mr->range[i].flags &= ~IP_NAT_RANGE_FULL;
++
++	return ret;
++}
++
++static inline int
++helper_cmp(const struct ip_nat_helper *helper,
++	   const struct ip_conntrack_tuple *tuple)
++{
++	return ip_ct_tuple_mask_cmp(tuple, &helper->tuple, &helper->mask);
++}
++
++/* Where to manip the reply packets (will be reverse manip). */
++static unsigned int opposite_hook[NF_IP_NUMHOOKS]
++= { [NF_IP_PRE_ROUTING] = NF_IP_POST_ROUTING,
++    [NF_IP_POST_ROUTING] = NF_IP_PRE_ROUTING,
++#ifdef CONFIG_IP_NF_NAT_LOCAL
++    [NF_IP_LOCAL_OUT] = NF_IP_LOCAL_IN,
++    [NF_IP_LOCAL_IN] = NF_IP_LOCAL_OUT,
++#endif
++};
++
++unsigned int
++ip_nat_setup_info(struct ip_conntrack *conntrack,
++		  const struct ip_nat_multi_range *mr,
++		  unsigned int hooknum)
++{
++	struct ip_conntrack_tuple new_tuple, inv_tuple, reply;
++	struct ip_conntrack_tuple orig_tp;
++	struct ip_nat_info *info = &conntrack->nat.info;
++	int in_hashes = info->initialized;
++
++	MUST_BE_WRITE_LOCKED(&ip_nat_lock);
++	IP_NF_ASSERT(hooknum == NF_IP_PRE_ROUTING
++		     || hooknum == NF_IP_POST_ROUTING
++		     || hooknum == NF_IP_LOCAL_IN
++		     || hooknum == NF_IP_LOCAL_OUT);
++	IP_NF_ASSERT(info->num_manips < IP_NAT_MAX_MANIPS);
++	IP_NF_ASSERT(!(info->initialized & (1 << HOOK2MANIP(hooknum))));
++
++	/* What we've got will look like inverse of reply. Normally
++	   this is what is in the conntrack, except for prior
++	   manipulations (future optimization: if num_manips == 0,
++	   orig_tp =
++	   conntrack->tuplehash[IP_CT_DIR_ORIGINAL].tuple) */
++	invert_tuplepr(&orig_tp,
++		       &conntrack->tuplehash[IP_CT_DIR_REPLY].tuple);
++
++#if 0
++	{
++	unsigned int i;
++
++	DEBUGP("Hook %u (%s), ", hooknum,
++	       HOOK2MANIP(hooknum)==IP_NAT_MANIP_SRC ? "SRC" : "DST");
++	DUMP_TUPLE(&orig_tp);
++	DEBUGP("Range %p: ", mr);
++	for (i = 0; i < mr->rangesize; i++) {
++		DEBUGP("%u:%s%s%s %u.%u.%u.%u - %u.%u.%u.%u %u - %u\n",
++		       i,
++		       (mr->range[i].flags & IP_NAT_RANGE_MAP_IPS)
++		       ? " MAP_IPS" : "",
++		       (mr->range[i].flags
++			& IP_NAT_RANGE_PROTO_SPECIFIED)
++		       ? " PROTO_SPECIFIED" : "",
++		       (mr->range[i].flags & IP_NAT_RANGE_FULL)
++		       ? " FULL" : "",
++		       NIPQUAD(mr->range[i].min_ip),
++		       NIPQUAD(mr->range[i].max_ip),
++		       mr->range[i].min.all,
++		       mr->range[i].max.all);
++	}
++	}
++#endif
++
++	do {
++		if (!get_unique_tuple(&new_tuple, &orig_tp, mr, conntrack,
++				      hooknum)) {
++			DEBUGP("ip_nat_setup_info: Can't get unique for %p.\n",
++			       conntrack);
++			return NF_DROP;
++		}
++
++#if 0
++		DEBUGP("Hook %u (%s) %p\n", hooknum,
++		       HOOK2MANIP(hooknum)==IP_NAT_MANIP_SRC ? "SRC" : "DST",
++		       conntrack);
++		DEBUGP("Original: ");
++		DUMP_TUPLE(&orig_tp);
++		DEBUGP("New: ");
++		DUMP_TUPLE(&new_tuple);
++#endif
++
++		/* We now have two tuples (SRCIP/SRCPT/DSTIP/DSTPT):
++		   the original (A/B/C/D') and the mangled one (E/F/G/H').
++
++		   We're only allowed to work with the SRC per-proto
++		   part, so we create inverses of both to start, then
++		   derive the other fields we need.  */
++
++		/* Reply connection: simply invert the new tuple
++                   (G/H/E/F') */
++		invert_tuplepr(&reply, &new_tuple);
++
++		/* Alter conntrack table so it recognizes replies.
++                   If fail this race (reply tuple now used), repeat. */
++	} while (!ip_conntrack_alter_reply(conntrack, &reply));
++
++	/* FIXME: We can simply used existing conntrack reply tuple
++           here --RR */
++	/* Create inverse of original: C/D/A/B' */
++	invert_tuplepr(&inv_tuple, &orig_tp);
++
++	/* Has source changed?. */
++	if (!ip_ct_tuple_src_equal(&new_tuple, &orig_tp)) {
++		/* In this direction, a source manip. */
++		info->manips[info->num_manips++] =
++			((struct ip_nat_info_manip)
++			 { IP_CT_DIR_ORIGINAL, hooknum,
++			   IP_NAT_MANIP_SRC, new_tuple.src });
++
++		IP_NF_ASSERT(info->num_manips < IP_NAT_MAX_MANIPS);
++
++		/* In the reverse direction, a destination manip. */
++		info->manips[info->num_manips++] =
++			((struct ip_nat_info_manip)
++			 { IP_CT_DIR_REPLY, opposite_hook[hooknum],
++			   IP_NAT_MANIP_DST, orig_tp.src });
++		IP_NF_ASSERT(info->num_manips <= IP_NAT_MAX_MANIPS);
++	}
++
++	/* Has destination changed? */
++	if (!ip_ct_tuple_dst_equal(&new_tuple, &orig_tp)) {
++		/* In this direction, a destination manip */
++		info->manips[info->num_manips++] =
++			((struct ip_nat_info_manip)
++			 { IP_CT_DIR_ORIGINAL, hooknum,
++			   IP_NAT_MANIP_DST, reply.src });
++
++		IP_NF_ASSERT(info->num_manips < IP_NAT_MAX_MANIPS);
++
++		/* In the reverse direction, a source manip. */
++		info->manips[info->num_manips++] =
++			((struct ip_nat_info_manip)
++			 { IP_CT_DIR_REPLY, opposite_hook[hooknum],
++			   IP_NAT_MANIP_SRC, inv_tuple.src });
++		IP_NF_ASSERT(info->num_manips <= IP_NAT_MAX_MANIPS);
++	}
++
++	/* If there's a helper, assign it; based on new tuple. */
++	if (!conntrack->master)
++		info->helper = LIST_FIND(&helpers, helper_cmp, struct ip_nat_helper *,
++					 &reply);
++
++	/* It's done. */
++	info->initialized |= (1 << HOOK2MANIP(hooknum));
++
++	if (in_hashes) {
++		IP_NF_ASSERT(info->bysource.conntrack);
++		replace_in_hashes(conntrack, info);
++	} else {
++		place_in_hashes(conntrack, info);
++	}
++
++	return NF_ACCEPT;
++}
++
++void replace_in_hashes(struct ip_conntrack *conntrack,
++		       struct ip_nat_info *info)
++{
++	/* Source has changed, so replace in hashes. */
++	unsigned int srchash
++		= hash_by_src(&conntrack->tuplehash[IP_CT_DIR_ORIGINAL]
++			      .tuple.src,
++			      conntrack->tuplehash[IP_CT_DIR_ORIGINAL]
++			      .tuple.dst.protonum);
++	/* We place packet as seen OUTGOUNG in byips_proto hash
++           (ie. reverse dst and src of reply packet. */
++	unsigned int ipsprotohash
++		= hash_by_ipsproto(conntrack->tuplehash[IP_CT_DIR_REPLY]
++				   .tuple.dst.ip,
++				   conntrack->tuplehash[IP_CT_DIR_REPLY]
++				   .tuple.src.ip,
++				   conntrack->tuplehash[IP_CT_DIR_REPLY]
++				   .tuple.dst.protonum);
++
++	IP_NF_ASSERT(info->bysource.conntrack == conntrack);
++	MUST_BE_WRITE_LOCKED(&ip_nat_lock);
++
++	list_del(&info->bysource.list);
++	list_del(&info->byipsproto.list);
++
++	list_prepend(&bysource[srchash], &info->bysource);
++	list_prepend(&byipsproto[ipsprotohash], &info->byipsproto);
++}
++
++void place_in_hashes(struct ip_conntrack *conntrack,
++		     struct ip_nat_info *info)
++{
++	unsigned int srchash
++		= hash_by_src(&conntrack->tuplehash[IP_CT_DIR_ORIGINAL]
++			      .tuple.src,
++			      conntrack->tuplehash[IP_CT_DIR_ORIGINAL]
++			      .tuple.dst.protonum);
++	/* We place packet as seen OUTGOUNG in byips_proto hash
++           (ie. reverse dst and src of reply packet. */
++	unsigned int ipsprotohash
++		= hash_by_ipsproto(conntrack->tuplehash[IP_CT_DIR_REPLY]
++				   .tuple.dst.ip,
++				   conntrack->tuplehash[IP_CT_DIR_REPLY]
++				   .tuple.src.ip,
++				   conntrack->tuplehash[IP_CT_DIR_REPLY]
++				   .tuple.dst.protonum);
++
++	IP_NF_ASSERT(!info->bysource.conntrack);
++
++	MUST_BE_WRITE_LOCKED(&ip_nat_lock);
++	info->byipsproto.conntrack = conntrack;
++	info->bysource.conntrack = conntrack;
++
++	list_prepend(&bysource[srchash], &info->bysource);
++	list_prepend(&byipsproto[ipsprotohash], &info->byipsproto);
++}
++
++static void
++manip_pkt(u_int16_t proto, struct iphdr *iph, size_t len,
++	  const struct ip_conntrack_manip *manip,
++	  enum ip_nat_manip_type maniptype,
++	  __u32 *nfcache)
++{
++	*nfcache |= NFC_ALTERED;
++	find_nat_proto(proto)->manip_pkt(iph, len, manip, maniptype);
++
++	if (maniptype == IP_NAT_MANIP_SRC) {
++		iph->check = ip_nat_cheat_check(~iph->saddr, manip->ip,
++						iph->check);
++		iph->saddr = manip->ip;
++	} else {
++		iph->check = ip_nat_cheat_check(~iph->daddr, manip->ip,
++						iph->check);
++		iph->daddr = manip->ip;
++	}
++#if 0
++	if (ip_fast_csum((u8 *)iph, iph->ihl) != 0)
++		DEBUGP("IP: checksum on packet bad.\n");
++
++	if (proto == IPPROTO_TCP) {
++		void *th = (u_int32_t *)iph + iph->ihl;
++		if (tcp_v4_check(th, len - 4*iph->ihl, iph->saddr, iph->daddr,
++				 csum_partial((char *)th, len-4*iph->ihl, 0)))
++			DEBUGP("TCP: checksum on packet bad\n");
++	}
++#endif
++}
++
++static inline int exp_for_packet(struct ip_conntrack_expect *exp,
++			         struct sk_buff **pskb)
++{
++	struct ip_conntrack_protocol *proto;
++	int ret = 1;
++
++	MUST_BE_READ_LOCKED(&ip_conntrack_lock);
++	proto = __ip_ct_find_proto((*pskb)->nh.iph->protocol);
++	if (proto->exp_matches_pkt)
++		ret = proto->exp_matches_pkt(exp, pskb);
++
++	return ret;
++}
++
++/* Do packet manipulations according to binding. */
++unsigned int
++do_bindings(struct ip_conntrack *ct,
++	    enum ip_conntrack_info ctinfo,
++	    struct ip_nat_info *info,
++	    unsigned int hooknum,
++	    struct sk_buff **pskb)
++{
++	unsigned int i;
++	struct ip_nat_helper *helper;
++	enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
++	int is_tcp = (*pskb)->nh.iph->protocol == IPPROTO_TCP;
++
++	/* Need nat lock to protect against modification, but neither
++	   conntrack (referenced) and helper (deleted with
++	   synchronize_bh()) can vanish. */
++	READ_LOCK(&ip_nat_lock);
++	for (i = 0; i < info->num_manips; i++) {
++		/* raw socket (tcpdump) may have clone of incoming
++                   skb: don't disturb it --RR */
++		if (skb_cloned(*pskb) && !(*pskb)->sk) {
++			struct sk_buff *nskb = skb_copy(*pskb, GFP_ATOMIC);
++			if (!nskb) {
++				READ_UNLOCK(&ip_nat_lock);
++				return NF_DROP;
++			}
++			kfree_skb(*pskb);
++			*pskb = nskb;
++		}
++
++		if (info->manips[i].direction == dir
++		    && info->manips[i].hooknum == hooknum) {
++			DEBUGP("Mangling %p: %s to %u.%u.%u.%u %u\n",
++			       *pskb,
++			       info->manips[i].maniptype == IP_NAT_MANIP_SRC
++			       ? "SRC" : "DST",
++			       NIPQUAD(info->manips[i].manip.ip),
++			       htons(info->manips[i].manip.u.all));
++			manip_pkt((*pskb)->nh.iph->protocol,
++				  (*pskb)->nh.iph,
++				  (*pskb)->len,
++				  &info->manips[i].manip,
++				  info->manips[i].maniptype,
++				  &(*pskb)->nfcache);
++		}
++	}
++	helper = info->helper;
++	READ_UNLOCK(&ip_nat_lock);
++
++	if (helper) {
++		struct ip_conntrack_expect *exp = NULL;
++		struct list_head *cur_item;
++		int ret = NF_ACCEPT;
++		int helper_called = 0;
++
++		DEBUGP("do_bindings: helper existing for (%p)\n", ct);
++
++		/* Always defragged for helpers */
++		IP_NF_ASSERT(!((*pskb)->nh.iph->frag_off
++			       & htons(IP_MF|IP_OFFSET)));
++
++		/* Have to grab read lock before sibling_list traversal */
++		READ_LOCK(&ip_conntrack_lock);
++		list_for_each_prev(cur_item, &ct->sibling_list) { 
++			exp = list_entry(cur_item, struct ip_conntrack_expect, 
++					 expected_list);
++					 
++			/* if this expectation is already established, skip */
++			if (exp->sibling)
++				continue;
++
++			if (exp_for_packet(exp, pskb)) {
++				/* FIXME: May be true multiple times in the
++				 * case of UDP!! */
++				DEBUGP("calling nat helper (exp=%p) for	packet\n", exp);
++				ret = helper->help(ct, exp, info, ctinfo, 
++						   hooknum, pskb);
++				if (ret != NF_ACCEPT) {
++					READ_UNLOCK(&ip_conntrack_lock);
++					return ret;
++				}
++				helper_called = 1;
++			}
++		}
++		/* Helper might want to manip the packet even when there is no
++		 * matching expectation for this packet */
++		if (!helper_called && helper->flags & IP_NAT_HELPER_F_ALWAYS) {
++			DEBUGP("calling nat helper for packet without expectation\n");
++			ret = helper->help(ct, NULL, info, ctinfo, 
++					   hooknum, pskb);
++			if (ret != NF_ACCEPT) {
++				READ_UNLOCK(&ip_conntrack_lock);
++				return ret;
++			}
++		}
++		READ_UNLOCK(&ip_conntrack_lock);
++		
++		/* Adjust sequence number only once per packet 
++		 * (helper is called at all hooks) */
++		if (is_tcp && (hooknum == NF_IP_POST_ROUTING
++			       || hooknum == NF_IP_LOCAL_IN)) {
++			DEBUGP("ip_nat_core: adjusting sequence number\n");
++			/* future: put this in a l4-proto specific function,
++			 * and call this function here. */
++			ip_nat_seq_adjust(*pskb, ct, ctinfo);
++		}
++
++		return ret;
++
++	} else 
++		return NF_ACCEPT;
++
++	/* not reached */
++}
++
++unsigned int
++icmp_reply_translation(struct sk_buff *skb,
++		       struct ip_conntrack *conntrack,
++		       unsigned int hooknum,
++		       int dir)
++{
++	struct iphdr *iph = skb->nh.iph;
++	struct icmphdr *hdr = (struct icmphdr *)((u_int32_t *)iph + iph->ihl);
++	struct iphdr *inner = (struct iphdr *)(hdr + 1);
++	size_t datalen = skb->len - ((void *)inner - (void *)iph);
++	unsigned int i;
++	struct ip_nat_info *info = &conntrack->nat.info;
++
++	IP_NF_ASSERT(skb->len >= iph->ihl*4 + sizeof(struct icmphdr));
++	/* Must be RELATED */
++	IP_NF_ASSERT(skb->nfct
++		     - ((struct ip_conntrack *)skb->nfct->master)->infos
++		     == IP_CT_RELATED
++		     || skb->nfct
++		     - ((struct ip_conntrack *)skb->nfct->master)->infos
++		     == IP_CT_RELATED+IP_CT_IS_REPLY);
++
++	/* Redirects on non-null nats must be dropped, else they'll
++           start talking to each other without our translation, and be
++           confused... --RR */
++	if (hdr->type == ICMP_REDIRECT) {
++		/* Don't care about races here. */
++		if (info->initialized
++		    != ((1 << IP_NAT_MANIP_SRC) | (1 << IP_NAT_MANIP_DST))
++		    || info->num_manips != 0)
++			return NF_DROP;
++	}
++
++	DEBUGP("icmp_reply_translation: translating error %p hook %u dir %s\n",
++	       skb, hooknum, dir == IP_CT_DIR_ORIGINAL ? "ORIG" : "REPLY");
++	/* Note: May not be from a NAT'd host, but probably safest to
++	   do translation always as if it came from the host itself
++	   (even though a "host unreachable" coming from the host
++	   itself is a bit weird).
++
++	   More explanation: some people use NAT for anonymizing.
++	   Also, CERT recommends dropping all packets from private IP
++	   addresses (although ICMP errors from internal links with
++	   such addresses are not too uncommon, as Alan Cox points
++	   out) */
++
++	READ_LOCK(&ip_nat_lock);
++	for (i = 0; i < info->num_manips; i++) {
++		DEBUGP("icmp_reply: manip %u dir %s hook %u\n",
++		       i, info->manips[i].direction == IP_CT_DIR_ORIGINAL ?
++		       "ORIG" : "REPLY", info->manips[i].hooknum);
++
++		if (info->manips[i].direction != dir)
++			continue;
++
++		/* Mapping the inner packet is just like a normal
++		   packet, except it was never src/dst reversed, so
++		   where we would normally apply a dst manip, we apply
++		   a src, and vice versa. */
++		if (info->manips[i].hooknum == hooknum) {
++			DEBUGP("icmp_reply: inner %s -> %u.%u.%u.%u %u\n",
++			       info->manips[i].maniptype == IP_NAT_MANIP_SRC
++			       ? "DST" : "SRC",
++			       NIPQUAD(info->manips[i].manip.ip),
++			       ntohs(info->manips[i].manip.u.udp.port));
++			manip_pkt(inner->protocol, inner,
++				  skb->len - ((void *)inner - (void *)iph),
++				  &info->manips[i].manip,
++				  !info->manips[i].maniptype,
++				  &skb->nfcache);
++			/* Outer packet needs to have IP header NATed like
++	                   it's a reply. */
++
++			/* Use mapping to map outer packet: 0 give no
++                           per-proto mapping */
++			DEBUGP("icmp_reply: outer %s -> %u.%u.%u.%u\n",
++			       info->manips[i].maniptype == IP_NAT_MANIP_SRC
++			       ? "SRC" : "DST",
++			       NIPQUAD(info->manips[i].manip.ip));
++			manip_pkt(0, iph, skb->len,
++				  &info->manips[i].manip,
++				  info->manips[i].maniptype,
++				  &skb->nfcache);
++		}
++	}
++	READ_UNLOCK(&ip_nat_lock);
++
++	/* Since we mangled inside ICMP packet, recalculate its
++	   checksum from scratch.  (Hence the handling of incorrect
++	   checksums in conntrack, so we don't accidentally fix one.)  */
++	hdr->checksum = 0;
++	hdr->checksum = ip_compute_csum((unsigned char *)hdr,
++					sizeof(*hdr) + datalen);
++
++	return NF_ACCEPT;
++}
++
++int __init ip_nat_init(void)
++{
++	size_t i;
++
++	/* Leave them the same for the moment. */
++	ip_nat_htable_size = ip_conntrack_htable_size;
++
++	/* One vmalloc for both hash tables */
++	bysource = vmalloc(sizeof(struct list_head) * ip_nat_htable_size*2);
++	if (!bysource) {
++		return -ENOMEM;
++	}
++	byipsproto = bysource + ip_nat_htable_size;
++
++	/* Sew in builtin protocols. */
++	WRITE_LOCK(&ip_nat_lock);
++	list_append(&protos, &ip_nat_protocol_tcp);
++	list_append(&protos, &ip_nat_protocol_udp);
++	list_append(&protos, &ip_nat_protocol_icmp);
++	WRITE_UNLOCK(&ip_nat_lock);
++
++	for (i = 0; i < ip_nat_htable_size; i++) {
++		INIT_LIST_HEAD(&bysource[i]);
++		INIT_LIST_HEAD(&byipsproto[i]);
++	}
++
++	/* FIXME: Man, this is a hack.  <SIGH> */
++	IP_NF_ASSERT(ip_conntrack_destroyed == NULL);
++	ip_conntrack_destroyed = &ip_nat_cleanup_conntrack;
++
++	return 0;
++}
++
++/* Clear NAT section of all conntracks, in case we're loaded again. */
++static int clean_nat(const struct ip_conntrack *i, void *data)
++{
++	memset((void *)&i->nat, 0, sizeof(i->nat));
++	return 0;
++}
++
++/* Not __exit: called from ip_nat_standalone.c:init_or_cleanup() --RR */
++void ip_nat_cleanup(void)
++{
++	ip_ct_selective_cleanup(&clean_nat, NULL);
++	ip_conntrack_destroyed = NULL;
++	vfree(bysource);
++}
+diff -uNr linux_org/net/ipv4/netfilter/ip_nat_pptp.c linux/net/ipv4/netfilter/ip_nat_pptp.c
+--- linux_org/net/ipv4/netfilter/ip_nat_pptp.c	1970-01-01 01:00:00.000000000 +0100
++++ linux/net/ipv4/netfilter/ip_nat_pptp.c	2006-10-27 14:11:52.000000000 +0200
+@@ -0,0 +1,475 @@
++/*
++ * ip_nat_pptp.c	- Version 1.5
++ *
++ * NAT support for PPTP (Point to Point Tunneling Protocol).
++ * PPTP is a a protocol for creating virtual private networks.
++ * It is a specification defined by Microsoft and some vendors
++ * working with Microsoft.  PPTP is built on top of a modified
++ * version of the Internet Generic Routing Encapsulation Protocol.
++ * GRE is defined in RFC 1701 and RFC 1702.  Documentation of
++ * PPTP can be found in RFC 2637
++ *
++ * (C) 2000-2003 by Harald Welte <laforge@gnumonks.org>
++ *
++ * Development of this code funded by Astaro AG (http://www.astaro.com/)
++ *
++ * TODO: - Support for multiple calls within one session
++ * 	   (needs netfilter newnat code)
++ * 	 - NAT to a unique tuple, not to TCP source port
++ * 	   (needs netfilter tuple reservation)
++ *
++ * Changes:
++ *     2002-02-10 - Version 1.3
++ *       - Use ip_nat_mangle_tcp_packet() because of cloned skb's
++ *	   in local connections (Philip Craig <philipc@snapgear.com>)
++ *       - add checks for magicCookie and pptp version
++ *       - make argument list of pptp_{out,in}bound_packet() shorter
++ *       - move to C99 style initializers
++ *       - print version number at module loadtime
++ *     2003-09-22 - Version 1.5
++ *       - use SNATed tcp sourceport as callid, since we get called before
++ *         TCP header is mangled (Philip Craig <philipc@snapgear.com>)
++ * 
++ */
++
++#include <linux/config.h>
++#include <linux/module.h>
++#include <linux/ip.h>
++#include <linux/tcp.h>
++#include <net/tcp.h>
++#include <linux/netfilter_ipv4/ip_nat.h>
++#include <linux/netfilter_ipv4/ip_nat_rule.h>
++#include <linux/netfilter_ipv4/ip_nat_helper.h>
++#include <linux/netfilter_ipv4/ip_nat_pptp.h>
++#include <linux/netfilter_ipv4/ip_conntrack_helper.h>
++#include <linux/netfilter_ipv4/ip_conntrack_proto_gre.h>
++#include <linux/netfilter_ipv4/ip_conntrack_pptp.h>
++
++#define IP_NAT_PPTP_VERSION "1.5"
++
++MODULE_LICENSE("GPL");
++MODULE_AUTHOR("Harald Welte <laforge@gnumonks.org>");
++MODULE_DESCRIPTION("Netfilter NAT helper module for PPTP");
++
++
++#if 0
++#include "ip_conntrack_pptp_priv.h"
++#define DEBUGP(format, args...) printk(KERN_DEBUG __FILE__ ":" __FUNCTION__ \
++				       ": " format, ## args)
++#else
++#define DEBUGP(format, args...)
++#endif
++
++static unsigned int
++pptp_nat_expected(struct sk_buff **pskb,
++		  unsigned int hooknum,
++		  struct ip_conntrack *ct,
++		  struct ip_nat_info *info)
++{
++	struct ip_conntrack *master = master_ct(ct);
++	struct ip_nat_multi_range mr;
++	struct ip_ct_pptp_master *ct_pptp_info;
++	struct ip_nat_pptp *nat_pptp_info;
++	u_int32_t newip, newcid;
++	int ret;
++
++	IP_NF_ASSERT(info);
++	IP_NF_ASSERT(master);
++	IP_NF_ASSERT(!(info->initialized & (1 << HOOK2MANIP(hooknum))));
++
++	DEBUGP("we have a connection!\n");
++
++	LOCK_BH(&ip_pptp_lock);
++	ct_pptp_info = &master->help.ct_pptp_info;
++	nat_pptp_info = &master->nat.help.nat_pptp_info;
++
++	/* need to alter GRE tuple because conntrack expectfn() used 'wrong'
++	 * (unmanipulated) values */
++	if (HOOK2MANIP(hooknum) == IP_NAT_MANIP_DST) {
++		DEBUGP("completing tuples with NAT info \n");
++		/* we can do this, since we're unconfirmed */
++		if (ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.gre.key ==
++			htonl(ct_pptp_info->pac_call_id)) {	
++			/* assume PNS->PAC */
++			ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.gre.key =
++				htonl(nat_pptp_info->pns_call_id);
++			ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u.gre.key =
++				htonl(nat_pptp_info->pns_call_id);
++			newip = master->tuplehash[IP_CT_DIR_REPLY].tuple.src.ip;
++			newcid = htonl(nat_pptp_info->pac_call_id);
++		} else {
++			/* assume PAC->PNS */
++			ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.gre.key =
++				htonl(nat_pptp_info->pac_call_id);
++			ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u.gre.key =
++				htonl(nat_pptp_info->pac_call_id);
++			newip = master->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip;
++			newcid = htonl(nat_pptp_info->pns_call_id);
++		}
++	} else {
++		if (ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.gre.key ==
++			htonl(ct_pptp_info->pac_call_id)) {	
++			/* assume PNS->PAC */
++			newip = master->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip;
++			newcid = htonl(ct_pptp_info->pns_call_id);
++		}
++		else {
++			/* assume PAC->PNS */
++			newip = master->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.ip;
++			newcid = htonl(ct_pptp_info->pac_call_id);
++		}
++	}
++
++	mr.rangesize = 1;
++	mr.range[0].flags = IP_NAT_RANGE_MAP_IPS | IP_NAT_RANGE_PROTO_SPECIFIED;
++	mr.range[0].min_ip = mr.range[0].max_ip = newip;
++	mr.range[0].min = mr.range[0].max = 
++		((union ip_conntrack_manip_proto ) { newcid }); 
++	DEBUGP("change ip to %u.%u.%u.%u\n", 
++		NIPQUAD(newip));
++	DEBUGP("change key to 0x%x\n", ntohl(newcid));
++	ret = ip_nat_setup_info(ct, &mr, hooknum);
++
++	UNLOCK_BH(&ip_pptp_lock);
++
++	return ret;
++
++}
++
++/* outbound packets == from PNS to PAC */
++static inline unsigned int
++pptp_outbound_pkt(struct sk_buff **pskb,
++		  struct ip_conntrack *ct,
++		  enum ip_conntrack_info ctinfo,
++		  struct ip_conntrack_expect *exp)
++
++{
++	struct iphdr *iph = (*pskb)->nh.iph;
++	struct tcphdr *tcph = (void *) iph + iph->ihl*4;
++	struct pptp_pkt_hdr *pptph = (struct pptp_pkt_hdr *) 
++					((void *)tcph + tcph->doff*4);
++
++	struct PptpControlHeader *ctlh;
++	union pptp_ctrl_union pptpReq;
++	struct ip_ct_pptp_master *ct_pptp_info = &ct->help.ct_pptp_info;
++	struct ip_nat_pptp *nat_pptp_info = &ct->nat.help.nat_pptp_info;
++
++	u_int16_t msg, *cid = NULL, new_callid;
++
++	/* FIXME: size checks !!! */
++	ctlh = (struct PptpControlHeader *) ((void *) pptph + sizeof(*pptph));
++	pptpReq.rawreq = (void *) ((void *) ctlh + sizeof(*ctlh));
++
++	new_callid = htons(ct_pptp_info->pns_call_id);
++	
++	switch (msg = ntohs(ctlh->messageType)) {
++		case PPTP_OUT_CALL_REQUEST:
++			cid = &pptpReq.ocreq->callID;
++			/* FIXME: ideally we would want to reserve a call ID
++			 * here.  current netfilter NAT core is not able to do
++			 * this :( For now we use TCP source port. This breaks
++			 * multiple calls within one control session */
++
++			/* save original call ID in nat_info */
++			nat_pptp_info->pns_call_id = ct_pptp_info->pns_call_id;
++
++			/* don't use tcph->source since we are at a DSTmanip
++			 * hook (e.g. PREROUTING) and pkt is not mangled yet */
++			new_callid = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.u.tcp.port;
++
++			/* save new call ID in ct info */
++			ct_pptp_info->pns_call_id = ntohs(new_callid);
++			break;
++		case PPTP_IN_CALL_REPLY:
++			cid = &pptpReq.icreq->callID;
++			break;
++		case PPTP_CALL_CLEAR_REQUEST:
++			cid = &pptpReq.clrreq->callID;
++			break;
++		default:
++			DEBUGP("unknown outbound packet 0x%04x:%s\n", msg,
++			      (msg <= PPTP_MSG_MAX)? strMName[msg]:strMName[0]);
++			/* fall through */
++
++		case PPTP_SET_LINK_INFO:
++			/* only need to NAT in case PAC is behind NAT box */
++		case PPTP_START_SESSION_REQUEST:
++		case PPTP_START_SESSION_REPLY:
++		case PPTP_STOP_SESSION_REQUEST:
++		case PPTP_STOP_SESSION_REPLY:
++		case PPTP_ECHO_REQUEST:
++		case PPTP_ECHO_REPLY:
++			/* no need to alter packet */
++			return NF_ACCEPT;
++	}
++
++	IP_NF_ASSERT(cid);
++
++	DEBUGP("altering call id from 0x%04x to 0x%04x\n",
++		ntohs(*cid), ntohs(new_callid));
++
++	/* mangle packet */
++	ip_nat_mangle_tcp_packet(pskb, ct, ctinfo, (void *)cid - (void *)pptph,
++				 sizeof(new_callid), (char *)&new_callid,
++				 sizeof(new_callid));
++
++	return NF_ACCEPT;
++}
++
++/* inbound packets == from PAC to PNS */
++static inline unsigned int
++pptp_inbound_pkt(struct sk_buff **pskb,
++		 struct ip_conntrack *ct,
++		 enum ip_conntrack_info ctinfo,
++		 struct ip_conntrack_expect *oldexp)
++{
++	struct iphdr *iph = (*pskb)->nh.iph;
++	struct tcphdr *tcph = (void *) iph + iph->ihl*4;
++	struct pptp_pkt_hdr *pptph = (struct pptp_pkt_hdr *) 
++					((void *)tcph + tcph->doff*4);
++
++	struct PptpControlHeader *ctlh;
++	union pptp_ctrl_union pptpReq;
++	struct ip_ct_pptp_master *ct_pptp_info = &ct->help.ct_pptp_info;
++	struct ip_nat_pptp *nat_pptp_info = &ct->nat.help.nat_pptp_info;
++
++	u_int16_t msg, new_cid = 0, new_pcid, *pcid = NULL, *cid = NULL;
++	u_int32_t old_dst_ip;
++
++	struct ip_conntrack_tuple t, inv_t;
++	struct ip_conntrack_tuple *orig_t, *reply_t;
++
++	/* FIXME: size checks !!! */
++	ctlh = (struct PptpControlHeader *) ((void *) pptph + sizeof(*pptph));
++	pptpReq.rawreq = (void *) ((void *) ctlh + sizeof(*ctlh));
++
++	new_pcid = htons(nat_pptp_info->pns_call_id);
++
++	switch (msg = ntohs(ctlh->messageType)) {
++	case PPTP_OUT_CALL_REPLY:
++		pcid = &pptpReq.ocack->peersCallID;	
++		cid = &pptpReq.ocack->callID;
++		if (!oldexp) {
++			DEBUGP("outcall but no expectation\n");
++			break;
++		}
++		old_dst_ip = oldexp->tuple.dst.ip;
++		t = oldexp->tuple;
++		invert_tuplepr(&inv_t, &t);
++
++		/* save original PAC call ID in nat_info */
++		nat_pptp_info->pac_call_id = ct_pptp_info->pac_call_id;
++
++		/* alter expectation */
++		orig_t = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
++		reply_t = &ct->tuplehash[IP_CT_DIR_REPLY].tuple;
++		if (t.src.ip == orig_t->src.ip && t.dst.ip == orig_t->dst.ip) {
++			/* expectation for PNS->PAC direction */
++			t.src.u.gre.key = htonl(nat_pptp_info->pns_call_id);
++			t.dst.u.gre.key = htonl(ct_pptp_info->pac_call_id);
++			inv_t.src.ip = reply_t->src.ip;
++			inv_t.dst.ip = reply_t->dst.ip;
++			inv_t.src.u.gre.key = htonl(nat_pptp_info->pac_call_id);
++			inv_t.dst.u.gre.key = htonl(ct_pptp_info->pns_call_id);
++		} else {
++			/* expectation for PAC->PNS direction */
++			t.src.u.gre.key = htonl(nat_pptp_info->pac_call_id);
++			t.dst.u.gre.key = htonl(ct_pptp_info->pns_call_id);
++			inv_t.src.ip = orig_t->src.ip;
++			inv_t.dst.ip = orig_t->dst.ip;
++			inv_t.src.u.gre.key = htonl(nat_pptp_info->pns_call_id);
++			inv_t.dst.u.gre.key = htonl(ct_pptp_info->pac_call_id);
++		}
++
++		if (!ip_conntrack_change_expect(oldexp, &t)) {
++			DEBUGP("successfully changed expect\n");
++		} else {
++			DEBUGP("can't change expect\n");
++		}
++		ip_ct_gre_keymap_change(oldexp->proto.gre.keymap_orig, &t);
++		ip_ct_gre_keymap_change(oldexp->proto.gre.keymap_reply, &inv_t);
++		break;
++	case PPTP_IN_CALL_CONNECT:
++		pcid = &pptpReq.iccon->peersCallID;
++		if (!oldexp)
++			break;
++		old_dst_ip = oldexp->tuple.dst.ip;
++		t = oldexp->tuple;
++
++		/* alter expectation, no need for callID */
++		if (t.dst.ip == ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.ip) {
++			/* expectation for PNS->PAC direction */
++			t.src.ip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip;
++		} else {
++			/* expectation for PAC->PNS direction */
++			t.dst.ip = ct->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip;
++		}
++
++		if (!ip_conntrack_change_expect(oldexp, &t)) {
++			DEBUGP("successfully changed expect\n");
++		} else {
++			DEBUGP("can't change expect\n");
++		}
++		break;
++	case PPTP_IN_CALL_REQUEST:
++		/* only need to nat in case PAC is behind NAT box */
++		break;
++	case PPTP_WAN_ERROR_NOTIFY:
++		pcid = &pptpReq.wanerr->peersCallID;
++		break;
++	case PPTP_CALL_DISCONNECT_NOTIFY:
++		pcid = &pptpReq.disc->callID;
++		break;
++
++	default:
++		DEBUGP("unknown inbound packet %s\n",
++			(msg <= PPTP_MSG_MAX)? strMName[msg]:strMName[0]);
++		/* fall through */
++
++	case PPTP_START_SESSION_REQUEST:
++	case PPTP_START_SESSION_REPLY:
++	case PPTP_STOP_SESSION_REQUEST:
++	case PPTP_STOP_SESSION_REPLY:
++	case PPTP_ECHO_REQUEST:
++	case PPTP_ECHO_REPLY:
++		/* no need to alter packet */
++		return NF_ACCEPT;
++	}
++
++	/* mangle packet */
++	IP_NF_ASSERT(pcid);
++	DEBUGP("altering peer call id from 0x%04x to 0x%04x\n",
++		ntohs(*pcid), ntohs(new_pcid));
++	ip_nat_mangle_tcp_packet(pskb, ct, ctinfo, (void *)pcid - (void *)pptph,
++				 sizeof(new_pcid), (char *)&new_pcid, 
++				 sizeof(new_pcid));
++
++	if (new_cid) {
++		IP_NF_ASSERT(cid);
++		DEBUGP("altering call id from 0x%04x to 0x%04x\n",
++			ntohs(*cid), ntohs(new_cid));
++		ip_nat_mangle_tcp_packet(pskb, ct, ctinfo, 
++					 (void *)cid - (void *)pptph, 
++					 sizeof(new_cid), (char *)&new_cid, 
++					 sizeof(new_cid));
++	}
++
++	/* great, at least we don't need to resize packets */
++	return NF_ACCEPT;
++}
++
++
++static unsigned int tcp_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 = (*pskb)->nh.iph;
++	struct tcphdr *tcph = (void *) iph + iph->ihl*4;
++	unsigned int datalen = (*pskb)->len - iph->ihl*4 - tcph->doff*4;
++	struct pptp_pkt_hdr *pptph;
++
++	int dir;
++
++	DEBUGP("entering\n");
++
++	/* Only mangle things once: DST for original direction
++	   and SRC for reply direction. */
++	dir = CTINFO2DIR(ctinfo);
++	if (!((HOOK2MANIP(hooknum) == IP_NAT_MANIP_SRC
++	     && dir == IP_CT_DIR_ORIGINAL)
++	      || (HOOK2MANIP(hooknum) == IP_NAT_MANIP_DST
++		  && 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"
++		       : hooknum == NF_IP_LOCAL_IN ? "INPUT" : "???");
++		return NF_ACCEPT;
++	}
++
++	/* if packet is too small, just skip it */
++	if (datalen < sizeof(struct pptp_pkt_hdr)+
++		      sizeof(struct PptpControlHeader)) {
++		DEBUGP("pptp packet too short\n");
++		return NF_ACCEPT;	
++	}
++
++	pptph = (struct pptp_pkt_hdr *) ((void *)tcph + tcph->doff*4);
++
++	/* if it's not a control message, we can't handle it */
++	if (ntohs(pptph->packetType) != PPTP_PACKET_CONTROL ||
++	    ntohl(pptph->magicCookie) != PPTP_MAGIC_COOKIE) {
++		DEBUGP("not a pptp control packet\n");
++		return NF_ACCEPT;
++	}
++
++	LOCK_BH(&ip_pptp_lock);
++
++	if (dir == IP_CT_DIR_ORIGINAL) {
++		/* reuqests sent by client to server (PNS->PAC) */
++		pptp_outbound_pkt(pskb, ct, ctinfo, exp);
++	} else {
++		/* response from the server to the client (PAC->PNS) */
++		pptp_inbound_pkt(pskb, ct, ctinfo, exp);
++	}
++
++	UNLOCK_BH(&ip_pptp_lock);
++
++	return NF_ACCEPT;
++}
++
++/* nat helper struct for control connection */
++static struct ip_nat_helper pptp_tcp_helper = { 
++	.list = { NULL, NULL },
++	.name = "pptp", 
++	.flags = IP_NAT_HELPER_F_ALWAYS, 
++	.me = THIS_MODULE,
++	.tuple = { .src = { .ip = 0, 
++			    .u = { .tcp = { .port = 
++				    	__constant_htons(PPTP_CONTROL_PORT) } 
++				 } 
++			  },
++	  	   .dst = { .ip = 0, 
++			    .u = { .all = 0 }, 
++			    .protonum = IPPROTO_TCP 
++		   	  } 
++		 },
++
++	.mask = { .src = { .ip = 0, 
++			   .u = { .tcp = { .port = 0xFFFF } } 
++			 },
++		  .dst = { .ip = 0, 
++			   .u = { .all = 0 }, 
++			   .protonum = 0xFFFF 
++		  	 } 
++		},
++	.help = tcp_help, 
++	.expect = pptp_nat_expected 
++};
++
++			  
++static int __init init(void)
++{
++	DEBUGP("%s: registering NAT helper\n", __FILE__);
++	if (ip_nat_helper_register(&pptp_tcp_helper)) {
++		printk(KERN_ERR "Unable to register NAT application helper "
++				"for pptp\n");
++		return -EIO;
++	}
++
++	printk("ip_nat_pptp version %s loaded\n", IP_NAT_PPTP_VERSION);
++	return 0;
++}
++
++static void __exit fini(void)
++{
++	DEBUGP("cleanup_module\n" );
++	ip_nat_helper_unregister(&pptp_tcp_helper);
++	printk("ip_nat_pptp version %s unloaded\n", IP_NAT_PPTP_VERSION);
++}
++
++module_init(init);
++module_exit(fini);
+diff -uNr linux_org/net/ipv4/netfilter/ip_nat_proto_gre.c linux/net/ipv4/netfilter/ip_nat_proto_gre.c
+--- linux_org/net/ipv4/netfilter/ip_nat_proto_gre.c	1970-01-01 01:00:00.000000000 +0100
++++ linux/net/ipv4/netfilter/ip_nat_proto_gre.c	2006-10-27 14:11:52.000000000 +0200
+@@ -0,0 +1,225 @@
++/*
++ * ip_nat_proto_gre.c - Version 1.2
++ *
++ * NAT protocol helper module for GRE.
++ *
++ * GRE is a generic encapsulation protocol, which is generally not very
++ * suited for NAT, as it has no protocol-specific part as port numbers.
++ *
++ * It has an optional key field, which may help us distinguishing two 
++ * connections between the same two hosts.
++ *
++ * GRE is defined in RFC 1701 and RFC 1702, as well as RFC 2784 
++ *
++ * PPTP is built on top of a modified version of GRE, and has a mandatory
++ * field called "CallID", which serves us for the same purpose as the key
++ * field in plain GRE.
++ *
++ * Documentation about PPTP can be found in RFC 2637
++ *
++ * (C) 2000-2003 by Harald Welte <laforge@gnumonks.org>
++ *
++ * Development of this code funded by Astaro AG (http://www.astaro.com/)
++ *
++ */
++
++#include <linux/config.h>
++#include <linux/module.h>
++#include <linux/ip.h>
++#include <linux/netfilter_ipv4/ip_nat.h>
++#include <linux/netfilter_ipv4/ip_nat_rule.h>
++#include <linux/netfilter_ipv4/ip_nat_protocol.h>
++#include <linux/netfilter_ipv4/ip_conntrack_proto_gre.h>
++
++MODULE_LICENSE("GPL");
++MODULE_AUTHOR("Harald Welte <laforge@gnumonks.org>");
++MODULE_DESCRIPTION("Netfilter NAT protocol helper module for GRE");
++
++#if 0
++#define DEBUGP(format, args...) printk(KERN_DEBUG __FILE__ ":" __FUNCTION__ \
++				       ": " format, ## args)
++#else
++#define DEBUGP(x, args...)
++#endif
++
++/* is key in given range between min and max */
++static int
++gre_in_range(const struct ip_conntrack_tuple *tuple,
++	     enum ip_nat_manip_type maniptype,
++	     const union ip_conntrack_manip_proto *min,
++	     const union ip_conntrack_manip_proto *max)
++{
++	u_int32_t key;
++
++	if (maniptype == IP_NAT_MANIP_SRC)
++		key = tuple->src.u.gre.key;
++	else
++		key = tuple->dst.u.gre.key;
++
++	return ntohl(key) >= ntohl(min->gre.key)
++		&& ntohl(key) <= ntohl(max->gre.key);
++}
++
++/* generate unique tuple ... */
++static int 
++gre_unique_tuple(struct ip_conntrack_tuple *tuple,
++		 const struct ip_nat_range *range,
++		 enum ip_nat_manip_type maniptype,
++		 const struct ip_conntrack *conntrack)
++{
++	u_int32_t min, i, range_size;
++	u_int32_t key = 0, *keyptr;
++
++	if (maniptype == IP_NAT_MANIP_SRC)
++		keyptr = &tuple->src.u.gre.key;
++	else
++		keyptr = &tuple->dst.u.gre.key;
++
++	if (!(range->flags & IP_NAT_RANGE_PROTO_SPECIFIED)) {
++
++		switch (tuple->dst.u.gre.version) {
++		case 0:
++			DEBUGP("NATing GRE version 0 (ct=%p)\n",
++				conntrack);
++			min = 1;
++			range_size = 0xffffffff;
++			break;
++		case GRE_VERSION_PPTP:
++			DEBUGP("%p: NATing GRE PPTP\n", 
++				conntrack);
++			min = 1;
++			range_size = 0xffff;
++			break;
++		default:
++			printk(KERN_WARNING "nat_gre: unknown GRE version\n");
++			return 0;
++			break;
++		}
++
++	} else {
++		min = ntohl(range->min.gre.key);
++		range_size = ntohl(range->max.gre.key) - min + 1;
++	}
++
++	DEBUGP("min = %u, range_size = %u\n", min, range_size); 
++
++	for (i = 0; i < range_size; i++, key++) {
++		*keyptr = htonl(min + key % range_size);
++		if (!ip_nat_used_tuple(tuple, conntrack))
++			return 1;
++	}
++
++	DEBUGP("%p: no NAT mapping\n", conntrack);
++
++	return 0;
++}
++
++/* manipulate a GRE packet according to maniptype */
++static void 
++gre_manip_pkt(struct iphdr *iph, size_t len, 
++	      const struct ip_conntrack_manip *manip,
++	      enum ip_nat_manip_type maniptype)
++{
++	struct gre_hdr *greh = (struct gre_hdr *)((u_int32_t *)iph+iph->ihl);
++	struct gre_hdr_pptp *pgreh = (struct gre_hdr_pptp *) greh;
++
++	/* we only have destination manip of a packet, since 'source key' 
++	 * is not present in the packet itself */
++	if (maniptype == IP_NAT_MANIP_DST) {
++		/* key manipulation is always dest */
++		switch (greh->version) {
++		case 0:
++			if (!greh->key) {
++				DEBUGP("can't nat GRE w/o key\n");
++				break;
++			}
++			if (greh->csum) {
++				/* FIXME: Never tested this code... */
++				*(gre_csum(greh)) = 
++					ip_nat_cheat_check(~*(gre_key(greh)),
++							manip->u.gre.key,
++							*(gre_csum(greh)));
++			}
++			*(gre_key(greh)) = manip->u.gre.key;
++			break;
++		case GRE_VERSION_PPTP:
++			DEBUGP("call_id -> 0x%04x\n", 
++				ntohl(manip->u.gre.key));
++			pgreh->call_id = htons(ntohl(manip->u.gre.key));
++			break;
++		default:
++			DEBUGP("can't nat unknown GRE version\n");
++			break;
++		}
++	}
++}
++
++/* print out a nat tuple */
++static unsigned int 
++gre_print(char *buffer, 
++	  const struct ip_conntrack_tuple *match,
++	  const struct ip_conntrack_tuple *mask)
++{
++	unsigned int len = 0;
++
++	if (mask->dst.u.gre.version)
++		len += sprintf(buffer + len, "version=%d ",
++				ntohs(match->dst.u.gre.version));
++
++	if (mask->dst.u.gre.protocol)
++		len += sprintf(buffer + len, "protocol=0x%x ",
++				ntohs(match->dst.u.gre.protocol));
++
++	if (mask->src.u.gre.key)
++		len += sprintf(buffer + len, "srckey=0x%x ", 
++				ntohl(match->src.u.gre.key));
++
++	if (mask->dst.u.gre.key)
++		len += sprintf(buffer + len, "dstkey=0x%x ",
++				ntohl(match->src.u.gre.key));
++
++	return len;
++}
++
++/* print a range of keys */
++static unsigned int 
++gre_print_range(char *buffer, const struct ip_nat_range *range)
++{
++	if (range->min.gre.key != 0 
++	    || range->max.gre.key != 0xFFFF) {
++		if (range->min.gre.key == range->max.gre.key)
++			return sprintf(buffer, "key 0x%x ",
++					ntohl(range->min.gre.key));
++		else
++			return sprintf(buffer, "keys 0x%u-0x%u ",
++					ntohl(range->min.gre.key),
++					ntohl(range->max.gre.key));
++	} else
++		return 0;
++}
++
++/* nat helper struct */
++static struct ip_nat_protocol gre = 
++	{ { NULL, NULL }, "GRE", IPPROTO_GRE,
++	  gre_manip_pkt,
++	  gre_in_range,
++	  gre_unique_tuple,
++	  gre_print,
++	  gre_print_range 
++	};
++				  
++static int __init init(void)
++{
++        if (ip_nat_protocol_register(&gre))
++                return -EIO;
++
++        return 0;
++}
++
++static void __exit fini(void)
++{
++        ip_nat_protocol_unregister(&gre);
++}
++
++module_init(init);
++module_exit(fini);