2 * Copyright (c) 2001 Charles Mott <cm@linktel.net>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
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.
35 * This include file is intended to be used only within the aliasing
36 * software. Outside world interfaces are defined in alias.h
38 * This software is placed into the public domain with no restrictions
39 * on its distribution.
41 * Initial version: August, 1996 (cjm)
43 * <updated several times by original author and Eivind Eklund>
46 #ifndef _ALIAS_LOCAL_H_
47 #define _ALIAS_LOCAL_H_
49 #include <sys/queue.h>
51 /* Use kernel allocator. */
52 #if defined(_KERNEL) && defined(_SYS_MALLOC_H_)
53 MALLOC_DECLARE(M_ALIAS);
54 #define malloc(x) malloc(x, M_ALIAS, M_NOWAIT|M_ZERO)
55 #define calloc(x, n) malloc(x*n)
56 #define free(x) free(x, M_ALIAS)
59 /* XXX: LibAliasSetTarget() uses this constant. */
61 #define INADDR_NONE 0xffffffff
64 /* Sizes of input and output link tables */
65 #define LINK_TABLE_OUT_SIZE 101
66 #define LINK_TABLE_IN_SIZE 4001
71 LIST_ENTRY(libalias) instancelist;
73 int packetAliasMode; /* Mode flags */
74 /* - documented in alias.h */
76 struct in_addr aliasAddress; /* Address written onto source */
77 /* field of IP packet. */
79 struct in_addr targetAddress; /* IP address incoming packets */
80 /* are sent to if no aliasing */
81 /* link already exists */
83 struct in_addr nullAddress; /* Used as a dummy parameter for */
84 /* some function calls */
86 LIST_HEAD (, alias_link) linkTableOut[LINK_TABLE_OUT_SIZE];
87 /* Lookup table of pointers to */
88 /* chains of link records. Each */
90 LIST_HEAD (, alias_link) linkTableIn[LINK_TABLE_IN_SIZE];
91 /* link record is doubly indexed */
92 /* into input and output lookup */
101 int fragmentIdLinkCount;
102 int fragmentPtrLinkCount;
105 int cleanupIndex; /* Index to chain of link table */
106 /* being inspected for old links */
108 int timeStamp; /* System time in seconds for */
111 int lastCleanupTime; /* Last time
112 * IncrementalCleanup() */
115 int houseKeepingResidual; /* used by HouseKeeping() */
117 int deleteAllLinks; /* If equal to zero, DeleteLink() */
118 /* will not remove permanent links */
120 FILE *monitorFile; /* File descriptor for link */
122 /* statistics monitoring file */
124 int newDefaultLink; /* Indicates if a new aliasing */
125 /* link has been created after a */
126 /* call to PacketAliasIn/Out(). */
129 int fireWallFD; /* File descriptor to be able to */
130 /* control firewall. Opened by */
131 /* PacketAliasSetMode on first */
132 /* setting the PKT_ALIAS_PUNCH_FW */
134 int fireWallBaseNum; /* The first firewall entry
135 * free for our use */
136 int fireWallNumNums; /* How many entries can we
138 int fireWallActiveNum; /* Which entry did we last
140 char *fireWallField; /* bool array for entries */
143 unsigned int skinnyPort; /* TCP port used by the Skinny */
146 struct proxy_entry *proxyList;
148 struct in_addr true_addr; /* in network byte order. */
149 u_short true_port; /* in host byte order. */
156 * The following macro is used to update an
157 * internet checksum. "delta" is a 32-bit
158 * accumulation of all the changes to the
159 * checksum (adding in new 16-bit words and
160 * subtracting out old words), and "cksum"
161 * is the checksum value to be updated.
163 #define ADJUST_CHECKSUM(acc, cksum) \
168 acc = (acc >> 16) + (acc & 0xffff); \
170 cksum = (u_short) ~acc; \
172 acc = (acc >> 16) + (acc & 0xffff); \
174 cksum = (u_short) acc; \
182 * We do not calculate TCP checksums when libalias is a kernel
183 * module, since it has no idea about checksum offloading.
184 * If TCP data has changed, then we just set checksum to zero,
185 * and caller must recalculate it himself.
186 * In case if libalias will edit UDP data, the same approach
190 u_short IpChecksum(struct ip *_pip);
191 u_short TcpChecksum(struct ip *_pip);
194 DifferentialChecksum(u_short * _cksum, void * _new, void * _old, int _n);
196 /* Internal data access */
198 FindIcmpIn(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr,
199 u_short _id_alias, int _create);
201 FindIcmpOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr,
202 u_short _id, int _create);
204 FindFragmentIn1(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr,
207 FindFragmentIn2(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr,
210 AddFragmentPtrLink(struct libalias *la, struct in_addr _dst_addr, u_short _ip_id);
212 FindFragmentPtr(struct libalias *la, struct in_addr _dst_addr, u_short _ip_id);
214 FindProtoIn(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr,
217 FindProtoOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr,
220 FindUdpTcpIn(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr,
221 u_short _dst_port, u_short _alias_port, u_char _proto, int _create);
223 FindUdpTcpOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr,
224 u_short _src_port, u_short _dst_port, u_char _proto, int _create);
226 AddPptp(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr,
227 struct in_addr _alias_addr, u_int16_t _src_call_id);
229 FindPptpOutByCallId(struct libalias *la, struct in_addr _src_addr,
230 struct in_addr _dst_addr, u_int16_t _src_call_id);
232 FindPptpInByCallId(struct libalias *la, struct in_addr _dst_addr,
233 struct in_addr _alias_addr, u_int16_t _dst_call_id);
235 FindPptpOutByPeerCallId(struct libalias *la, struct in_addr _src_addr,
236 struct in_addr _dst_addr, u_int16_t _dst_call_id);
238 FindPptpInByPeerCallId(struct libalias *la, struct in_addr _dst_addr,
239 struct in_addr _alias_addr, u_int16_t _alias_call_id);
241 FindRtspOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr,
242 u_short _src_port, u_short _alias_port, u_char _proto);
244 FindOriginalAddress(struct libalias *la, struct in_addr _alias_addr);
246 FindAliasAddress(struct libalias *la, struct in_addr _original_addr);
248 /* External data access/modification */
250 FindNewPortGroup(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr,
251 u_short _src_port, u_short _dst_port, u_short _port_count,
252 u_char _proto, u_char _align);
253 void GetFragmentAddr(struct alias_link *_lnk, struct in_addr *_src_addr);
254 void SetFragmentAddr(struct alias_link *_lnk, struct in_addr _src_addr);
255 void GetFragmentPtr(struct alias_link *_lnk, char **_fptr);
256 void SetFragmentPtr(struct alias_link *_lnk, char *fptr);
257 void SetStateIn(struct alias_link *_lnk, int _state);
258 void SetStateOut(struct alias_link *_lnk, int _state);
259 int GetStateIn (struct alias_link *_lnk);
260 int GetStateOut(struct alias_link *_lnk);
262 GetOriginalAddress(struct alias_link *_lnk);
264 GetDestAddress(struct alias_link *_lnk);
266 GetAliasAddress(struct alias_link *_lnk);
268 GetDefaultAliasAddress(struct libalias *la);
269 void SetDefaultAliasAddress(struct libalias *la, struct in_addr _alias_addr);
270 u_short GetOriginalPort(struct alias_link *_lnk);
271 u_short GetAliasPort(struct alias_link *_lnk);
273 GetProxyAddress(struct alias_link *_lnk);
274 void SetProxyAddress(struct alias_link *_lnk, struct in_addr _addr);
275 u_short GetProxyPort(struct alias_link *_lnk);
276 void SetProxyPort(struct alias_link *_lnk, u_short _port);
277 void SetAckModified(struct alias_link *_lnk);
278 int GetAckModified(struct alias_link *_lnk);
279 int GetDeltaAckIn(struct ip *_pip, struct alias_link *_lnk);
280 int GetDeltaSeqOut(struct ip *_pip, struct alias_link *_lnk);
281 void AddSeq (struct ip *_pip, struct alias_link *_lnk, int _delta);
282 void SetExpire (struct alias_link *_lnk, int _expire);
283 void ClearCheckNewLink(struct libalias *la);
284 void SetProtocolFlags(struct alias_link *_lnk, int _pflags);
285 int GetProtocolFlags(struct alias_link *_lnk);
286 void SetDestCallId(struct alias_link *_lnk, u_int16_t _cid);
289 void PunchFWHole(struct alias_link *_lnk);
293 /* Housekeeping function */
294 void HouseKeeping(struct libalias *);
296 /* Tcp specfic routines */
297 /* lint -save -library Suppress flexelint warnings */
301 AliasHandleFtpOut(struct libalias *la, struct ip *_pip, struct alias_link *_lnk,
306 AliasHandleIrcOut(struct libalias *la, struct ip *_pip, struct alias_link *_lnk,
311 AliasHandleRtspOut(struct libalias *la, struct ip *_pip, struct alias_link *_lnk,
315 void AliasHandlePptpOut(struct libalias *la, struct ip *_pip, struct alias_link *_lnk);
316 void AliasHandlePptpIn(struct libalias *la, struct ip *_pip, struct alias_link *_lnk);
317 int AliasHandlePptpGreOut(struct libalias *la, struct ip *_pip);
318 int AliasHandlePptpGreIn(struct libalias *la, struct ip *_pip);
320 /* NetBIOS routines */
322 AliasHandleUdpNbt(struct libalias *la, struct ip *_pip, struct alias_link *_lnk,
323 struct in_addr *_alias_address, u_short _alias_port);
325 AliasHandleUdpNbtNS(struct libalias *la, struct ip *_pip, struct alias_link *_lnk,
326 struct in_addr *_alias_address, u_short * _alias_port,
327 struct in_addr *_original_address, u_short * _original_port);
329 /* CUSeeMe routines */
330 void AliasHandleCUSeeMeOut(struct libalias *la, struct ip *_pip, struct alias_link *_lnk);
331 void AliasHandleCUSeeMeIn(struct libalias *la, struct ip *_pip, struct in_addr _original_addr);
333 /* Skinny routines */
334 void AliasHandleSkinny(struct libalias *la, struct ip *_pip, struct alias_link *_lnk);
336 /* Transparent proxy routines */
338 ProxyCheck(struct libalias *la, struct ip *_pip, struct in_addr *_proxy_server_addr,
339 u_short * _proxy_server_port);
341 ProxyModify(struct libalias *la, struct alias_link *_lnk, struct ip *_pip,
342 int _maxpacketsize, int _proxy_type);
344 enum alias_tcp_state {
345 ALIAS_TCP_STATE_NOT_CONNECTED,
346 ALIAS_TCP_STATE_CONNECTED,
347 ALIAS_TCP_STATE_DISCONNECTED
350 #if defined(_NETINET_IP_H_)
351 static __inline void *
352 ip_next(struct ip *iphdr)
354 char *p = (char *)iphdr;
355 return (&p[iphdr->ip_hl * 4]);
359 #if defined(_NETINET_TCP_H_)
360 static __inline void *
361 tcp_next(struct tcphdr *tcphdr)
363 char *p = (char *)tcphdr;
364 return (&p[tcphdr->th_off * 4]);
368 #if defined(_NETINET_UDP_H_)
369 static __inline void *
370 udp_next(struct udphdr *udphdr)
372 return ((void *)(udphdr + 1));
378 #endif /* !_ALIAS_LOCAL_H_ */