alias_local.h revision 124621
1/*-
2 * Copyright (c) 2001 Charles Mott <cm@linktel.net>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: head/sys/netinet/libalias/alias_local.h 124621 2004-01-17 10:52:21Z phk $
27 */
28
29/*
30 * Alias_local.h contains the function prototypes for alias.c,
31 * alias_db.c, alias_util.c and alias_ftp.c, alias_irc.c (as well
32 * as any future add-ons).  It also includes macros, globals and
33 * struct definitions shared by more than one alias*.c file.
34 *
35 * This include file is intended to be used only within the aliasing
36 * software.  Outside world interfaces are defined in alias.h
37 *
38 * This software is placed into the public domain with no restrictions
39 * on its distribution.
40 *
41 * Initial version:  August, 1996  (cjm)
42 *
43 * <updated several times by original author and Eivind Eklund>
44 */
45
46#ifndef _ALIAS_LOCAL_H_
47#define	_ALIAS_LOCAL_H_
48
49#include <sys/queue.h>
50
51/* Sizes of input and output link tables */
52#define LINK_TABLE_OUT_SIZE         101
53#define LINK_TABLE_IN_SIZE         4001
54
55struct proxy_entry;
56
57struct libalias {
58	LIST_ENTRY(libalias)	instancelist;
59
60	int packetAliasMode;		/* Mode flags                      */
61					/*        - documented in alias.h  */
62
63	struct in_addr aliasAddress;	/* Address written onto source     */
64					/*   field of IP packet.           */
65
66	struct in_addr targetAddress;	/* IP address incoming packets     */
67					/*   are sent to if no aliasing    */
68					/*   link already exists           */
69
70	struct in_addr nullAddress;	/* Used as a dummy parameter for   */
71					/*   some function calls           */
72
73	LIST_HEAD(, alias_link) linkTableOut[LINK_TABLE_OUT_SIZE];
74					/* Lookup table of pointers to     */
75					/*   chains of link records. Each  */
76
77	LIST_HEAD(, alias_link) linkTableIn[LINK_TABLE_IN_SIZE];
78					/*   link record is doubly indexed */
79					/*   into input and output lookup  */
80					/*   tables.                       */
81
82					/* Link statistics                 */
83	int icmpLinkCount;
84	int udpLinkCount;
85	int tcpLinkCount;
86	int pptpLinkCount;
87	int protoLinkCount;
88	int fragmentIdLinkCount;
89	int fragmentPtrLinkCount;
90	int sockCount;
91
92	int cleanupIndex;		/* Index to chain of link table    */
93					/* being inspected for old links   */
94
95	int timeStamp;			/* System time in seconds for      */
96					/* current packet                  */
97
98	int lastCleanupTime;		/* Last time IncrementalCleanup()  */
99					/* was called                      */
100
101	int houseKeepingResidual;	/* used by HouseKeeping()          */
102
103	int deleteAllLinks;		/* If equal to zero, DeleteLink()  */
104					/* will not remove permanent links */
105
106	FILE *monitorFile;		/* File descriptor for link        */
107					/* statistics monitoring file      */
108
109	int newDefaultLink;		/* Indicates if a new aliasing     */
110					/* link has been created after a   */
111					/* call to PacketAliasIn/Out().    */
112
113#ifndef NO_FW_PUNCH
114	int fireWallFD;			/* File descriptor to be able to   */
115					/* control firewall.  Opened by    */
116					/* PacketAliasSetMode on first     */
117					/* setting the PKT_ALIAS_PUNCH_FW  */
118					/* flag.                           */
119	int fireWallBaseNum;     /* The first firewall entry free for our use */
120	int fireWallNumNums;     /* How many entries can we use? */
121	int fireWallActiveNum;   /* Which entry did we last use? */
122	char *fireWallField;     /* bool array for entries */
123#endif
124
125	unsigned int skinnyPort;	/* TCP port used by the Skinny     */
126					/* protocol.                       */
127
128	struct proxy_entry *proxyList;
129
130	struct in_addr true_addr;	/* in network byte order. */
131	u_short true_port;		/* in host byte order. */
132
133};
134
135/* Macros */
136
137/*
138 * The following macro is used to update an
139 * internet checksum.  "delta" is a 32-bit
140 * accumulation of all the changes to the
141 * checksum (adding in new 16-bit words and
142 * subtracting out old words), and "cksum"
143 * is the checksum value to be updated.
144 */
145#define	ADJUST_CHECKSUM(acc, cksum) \
146	do { \
147		acc += cksum; \
148		if (acc < 0) { \
149			acc = -acc; \
150			acc = (acc >> 16) + (acc & 0xffff); \
151			acc += acc >> 16; \
152			cksum = (u_short) ~acc; \
153		} else { \
154			acc = (acc >> 16) + (acc & 0xffff); \
155			acc += acc >> 16; \
156			cksum = (u_short) acc; \
157		} \
158	} while (0)
159
160
161/* Prototypes */
162
163/* General utilities */
164u_short	 IpChecksum(struct ip *_pip);
165u_short	 TcpChecksum(struct ip *_pip);
166void	 DifferentialChecksum(u_short *_cksum, u_short *_new, u_short *_old,
167	    int _n);
168
169/* Internal data access */
170struct alias_link *
171	 FindIcmpIn(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr,
172	    u_short _id_alias, int _create);
173struct alias_link *
174	 FindIcmpOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr,
175	    u_short _id, int _create);
176struct alias_link *
177	 FindFragmentIn1(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr,
178	    u_short _ip_id);
179struct alias_link *
180	 FindFragmentIn2(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr,
181	    u_short _ip_id);
182struct alias_link *
183	 AddFragmentPtrLink(struct libalias *la, struct in_addr _dst_addr, u_short _ip_id);
184struct alias_link *
185	 FindFragmentPtr(struct libalias *la, struct in_addr _dst_addr, u_short _ip_id);
186struct alias_link *
187	 FindProtoIn(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr,
188	    u_char _proto);
189struct alias_link *
190	 FindProtoOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr,
191	    u_char _proto);
192struct alias_link *
193	 FindUdpTcpIn(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr,
194	    u_short _dst_port, u_short _alias_port, u_char _proto, int _create);
195struct alias_link *
196	 FindUdpTcpOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr,
197	    u_short _src_port, u_short _dst_port, u_char _proto, int _create);
198struct alias_link *
199	 AddPptp(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr,
200	    struct in_addr _alias_addr, u_int16_t _src_call_id);
201struct alias_link *
202	 FindPptpOutByCallId(struct libalias *la, struct in_addr _src_addr,
203	    struct in_addr _dst_addr, u_int16_t _src_call_id);
204struct alias_link *
205	 FindPptpInByCallId(struct libalias *la, struct in_addr _dst_addr,
206	    struct in_addr _alias_addr, u_int16_t _dst_call_id);
207struct alias_link *
208	 FindPptpOutByPeerCallId(struct libalias *la, struct in_addr _src_addr,
209	    struct in_addr _dst_addr, u_int16_t _dst_call_id);
210struct alias_link *
211	 FindPptpInByPeerCallId(struct libalias *la, struct in_addr _dst_addr,
212	    struct in_addr _alias_addr, u_int16_t _alias_call_id);
213struct alias_link *
214	 FindRtspOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr,
215	    u_short _src_port, u_short _alias_port, u_char _proto);
216struct in_addr
217	 FindOriginalAddress(struct libalias *la, struct in_addr _alias_addr);
218struct in_addr
219	 FindAliasAddress(struct libalias *la, struct in_addr _original_addr);
220
221/* External data access/modification */
222int	 FindNewPortGroup(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr,
223                     u_short _src_port, u_short _dst_port, u_short _port_count,
224		     u_char _proto, u_char _align);
225void	 GetFragmentAddr(struct alias_link *_link, struct in_addr *_src_addr);
226void	 SetFragmentAddr(struct alias_link *_link, struct in_addr _src_addr);
227void	 GetFragmentPtr(struct alias_link *_link, char **_fptr);
228void	 SetFragmentPtr(struct alias_link *_link, char *fptr);
229void	 SetStateIn(struct alias_link *_link, int _state);
230void	 SetStateOut(struct alias_link *_link, int _state);
231int	 GetStateIn(struct alias_link *_link);
232int	 GetStateOut(struct alias_link *_link);
233struct in_addr
234	 GetOriginalAddress(struct alias_link *_link);
235struct in_addr
236	 GetDestAddress(struct alias_link *_link);
237struct in_addr
238	 GetAliasAddress(struct alias_link *_link);
239struct in_addr
240	 GetDefaultAliasAddress(struct libalias *la);
241void	 SetDefaultAliasAddress(struct libalias *la, struct in_addr _alias_addr);
242u_short	 GetOriginalPort(struct alias_link *_link);
243u_short	 GetAliasPort(struct alias_link *_link);
244struct in_addr
245	 GetProxyAddress(struct alias_link *_link);
246void	 SetProxyAddress(struct alias_link *_link, struct in_addr _addr);
247u_short	 GetProxyPort(struct alias_link *_link);
248void	 SetProxyPort(struct alias_link *_link, u_short _port);
249void	 SetAckModified(struct alias_link *_link);
250int	 GetAckModified(struct alias_link *_link);
251int	 GetDeltaAckIn(struct ip *_pip, struct alias_link *_link);
252int	 GetDeltaSeqOut(struct ip *_pip, struct alias_link *_link);
253void	 AddSeq(struct ip *_pip, struct alias_link *_link, int _delta);
254void	 SetExpire(struct alias_link *_link, int _expire);
255void	 ClearCheckNewLink(struct libalias *la);
256void	 SetProtocolFlags(struct alias_link *_link, int _pflags);
257int	 GetProtocolFlags(struct alias_link *_link);
258void	 SetDestCallId(struct alias_link *_link, u_int16_t _cid);
259#ifndef NO_FW_PUNCH
260void	 PunchFWHole(struct alias_link *_link);
261#endif
262
263/* Housekeeping function */
264void	 HouseKeeping(struct libalias *);
265
266/* Tcp specfic routines */
267/* lint -save -library Suppress flexelint warnings */
268
269/* FTP routines */
270void	 AliasHandleFtpOut(struct libalias *la, struct ip *_pip, struct alias_link *_link,
271	    int _maxpacketsize);
272
273/* IRC routines */
274void	 AliasHandleIrcOut(struct libalias *la, struct ip *_pip, struct alias_link *_link,
275	    int _maxsize);
276
277/* RTSP routines */
278void	 AliasHandleRtspOut(struct libalias *la, struct ip *_pip, struct alias_link *_link,
279	    int _maxpacketsize);
280
281/* PPTP routines */
282void	 AliasHandlePptpOut(struct libalias *la, struct ip *_pip, struct alias_link *_link);
283void	 AliasHandlePptpIn(struct libalias *la, struct ip *_pip, struct alias_link *_link);
284int	 AliasHandlePptpGreOut(struct libalias *la, struct ip *_pip);
285int	 AliasHandlePptpGreIn(struct libalias *la, struct ip *_pip);
286
287/* NetBIOS routines */
288int	 AliasHandleUdpNbt(struct libalias *la, struct ip *_pip, struct alias_link *_link,
289	    struct in_addr *_alias_address, u_short _alias_port);
290int	 AliasHandleUdpNbtNS(struct libalias *la, struct ip *_pip, struct alias_link *_link,
291	    struct in_addr *_alias_address, u_short *_alias_port,
292	    struct in_addr *_original_address, u_short *_original_port);
293
294/* CUSeeMe routines */
295void	 AliasHandleCUSeeMeOut(struct libalias *la, struct ip *_pip, struct alias_link *_link);
296void	 AliasHandleCUSeeMeIn(struct libalias *la, struct ip *_pip, struct in_addr _original_addr);
297
298/* Skinny routines */
299void	 AliasHandleSkinny(struct libalias *la, struct ip *_pip, struct alias_link *_link);
300
301/* Transparent proxy routines */
302int	 ProxyCheck(struct libalias *la, struct ip *_pip, struct in_addr *_proxy_server_addr,
303	    u_short *_proxy_server_port);
304void	 ProxyModify(struct libalias *la, struct alias_link *_link, struct ip *_pip,
305	    int _maxpacketsize, int _proxy_type);
306
307enum alias_tcp_state {
308	ALIAS_TCP_STATE_NOT_CONNECTED,
309	ALIAS_TCP_STATE_CONNECTED,
310	ALIAS_TCP_STATE_DISCONNECTED
311};
312
313/*lint -restore */
314
315#endif /* !_ALIAS_LOCAL_H_ */
316