alias_local.h revision 162674
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 162674 2006-09-26 23:26:53Z piso $ 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/types.h> 50#include <sys/sysctl.h> 51 52#ifdef _KERNEL 53#include <sys/malloc.h> 54#include <sys/lock.h> 55/* XXX: LibAliasSetTarget() uses this constant. */ 56#define INADDR_NONE 0xffffffff 57#endif 58 59/* Sizes of input and output link tables */ 60#define LINK_TABLE_OUT_SIZE 101 61#define LINK_TABLE_IN_SIZE 4001 62 63struct proxy_entry; 64 65struct libalias { 66 LIST_ENTRY(libalias) instancelist; 67 68 int packetAliasMode; /* Mode flags */ 69 /* - documented in alias.h */ 70 71 struct in_addr aliasAddress; /* Address written onto source */ 72 /* field of IP packet. */ 73 74 struct in_addr targetAddress; /* IP address incoming packets */ 75 /* are sent to if no aliasing */ 76 /* link already exists */ 77 78 struct in_addr nullAddress; /* Used as a dummy parameter for */ 79 /* some function calls */ 80 81 LIST_HEAD (, alias_link) linkTableOut[LINK_TABLE_OUT_SIZE]; 82 /* Lookup table of pointers to */ 83 /* chains of link records. Each */ 84 85 LIST_HEAD (, alias_link) linkTableIn[LINK_TABLE_IN_SIZE]; 86 /* link record is doubly indexed */ 87 /* into input and output lookup */ 88 /* tables. */ 89 90 /* Link statistics */ 91 int icmpLinkCount; 92 int udpLinkCount; 93 int tcpLinkCount; 94 int pptpLinkCount; 95 int protoLinkCount; 96 int fragmentIdLinkCount; 97 int fragmentPtrLinkCount; 98 int sockCount; 99 100 int cleanupIndex; /* Index to chain of link table */ 101 /* being inspected for old links */ 102 103 int timeStamp; /* System time in seconds for */ 104 /* current packet */ 105 106 int lastCleanupTime; /* Last time 107 * IncrementalCleanup() */ 108 /* was called */ 109 110 int houseKeepingResidual; /* used by HouseKeeping() */ 111 112 int deleteAllLinks; /* If equal to zero, DeleteLink() */ 113 /* will not remove permanent links */ 114 115 /* log descriptor */ 116#ifdef _KERNEL 117 char *logDesc; 118#else 119 FILE *logDesc; 120#endif 121 /* statistics monitoring */ 122 123 int newDefaultLink; /* Indicates if a new aliasing */ 124 /* link has been created after a */ 125 /* call to PacketAliasIn/Out(). */ 126 127#ifndef NO_FW_PUNCH 128 int fireWallFD; /* File descriptor to be able to */ 129 /* control firewall. Opened by */ 130 /* PacketAliasSetMode on first */ 131 /* setting the PKT_ALIAS_PUNCH_FW */ 132 /* flag. */ 133 int fireWallBaseNum; /* The first firewall entry 134 * free for our use */ 135 int fireWallNumNums; /* How many entries can we 136 * use? */ 137 int fireWallActiveNum; /* Which entry did we last 138 * use? */ 139 char *fireWallField; /* bool array for entries */ 140#endif 141 142 unsigned int skinnyPort; /* TCP port used by the Skinny */ 143 /* protocol. */ 144 145 struct proxy_entry *proxyList; 146 147 struct in_addr true_addr; /* in network byte order. */ 148 u_short true_port; /* in host byte order. */ 149 150}; 151 152/* Macros */ 153 154/* 155 * The following macro is used to update an 156 * internet checksum. "delta" is a 32-bit 157 * accumulation of all the changes to the 158 * checksum (adding in new 16-bit words and 159 * subtracting out old words), and "cksum" 160 * is the checksum value to be updated. 161 */ 162#define ADJUST_CHECKSUM(acc, cksum) \ 163 do { \ 164 acc += cksum; \ 165 if (acc < 0) { \ 166 acc = -acc; \ 167 acc = (acc >> 16) + (acc & 0xffff); \ 168 acc += acc >> 16; \ 169 cksum = (u_short) ~acc; \ 170 } else { \ 171 acc = (acc >> 16) + (acc & 0xffff); \ 172 acc += acc >> 16; \ 173 cksum = (u_short) acc; \ 174 } \ 175 } while (0) 176 177 178/* Prototypes */ 179 180/* 181 * We do not calculate TCP checksums when libalias is a kernel 182 * module, since it has no idea about checksum offloading. 183 * If TCP data has changed, then we just set checksum to zero, 184 * and caller must recalculate it himself. 185 * In case if libalias will edit UDP data, the same approach 186 * should be used. 187 */ 188#ifndef _KERNEL 189u_short IpChecksum(struct ip *_pip); 190u_short TcpChecksum(struct ip *_pip); 191#endif 192void 193DifferentialChecksum(u_short * _cksum, void * _new, void * _old, int _n); 194 195/* Internal data access */ 196struct alias_link * 197FindIcmpIn(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 198 u_short _id_alias, int _create); 199struct alias_link * 200FindIcmpOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr, 201 u_short _id, int _create); 202struct alias_link * 203FindFragmentIn1(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 204 u_short _ip_id); 205struct alias_link * 206FindFragmentIn2(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 207 u_short _ip_id); 208struct alias_link * 209 AddFragmentPtrLink(struct libalias *la, struct in_addr _dst_addr, u_short _ip_id); 210struct alias_link * 211 FindFragmentPtr(struct libalias *la, struct in_addr _dst_addr, u_short _ip_id); 212struct alias_link * 213FindProtoIn(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 214 u_char _proto); 215struct alias_link * 216FindProtoOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr, 217 u_char _proto); 218struct alias_link * 219FindUdpTcpIn(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 220 u_short _dst_port, u_short _alias_port, u_char _proto, int _create); 221struct alias_link * 222FindUdpTcpOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr, 223 u_short _src_port, u_short _dst_port, u_char _proto, int _create); 224struct alias_link * 225AddPptp(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr, 226 struct in_addr _alias_addr, u_int16_t _src_call_id); 227struct alias_link * 228FindPptpOutByCallId(struct libalias *la, struct in_addr _src_addr, 229 struct in_addr _dst_addr, u_int16_t _src_call_id); 230struct alias_link * 231FindPptpInByCallId(struct libalias *la, struct in_addr _dst_addr, 232 struct in_addr _alias_addr, u_int16_t _dst_call_id); 233struct alias_link * 234FindPptpOutByPeerCallId(struct libalias *la, struct in_addr _src_addr, 235 struct in_addr _dst_addr, u_int16_t _dst_call_id); 236struct alias_link * 237FindPptpInByPeerCallId(struct libalias *la, struct in_addr _dst_addr, 238 struct in_addr _alias_addr, u_int16_t _alias_call_id); 239struct alias_link * 240FindRtspOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr, 241 u_short _src_port, u_short _alias_port, u_char _proto); 242struct in_addr 243 FindOriginalAddress(struct libalias *la, struct in_addr _alias_addr); 244struct in_addr 245 FindAliasAddress(struct libalias *la, struct in_addr _original_addr); 246 247/* External data access/modification */ 248int 249FindNewPortGroup(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 250 u_short _src_port, u_short _dst_port, u_short _port_count, 251 u_char _proto, u_char _align); 252void GetFragmentAddr(struct alias_link *_lnk, struct in_addr *_src_addr); 253void SetFragmentAddr(struct alias_link *_lnk, struct in_addr _src_addr); 254void GetFragmentPtr(struct alias_link *_lnk, char **_fptr); 255void SetFragmentPtr(struct alias_link *_lnk, char *fptr); 256void SetStateIn(struct alias_link *_lnk, int _state); 257void SetStateOut(struct alias_link *_lnk, int _state); 258int GetStateIn (struct alias_link *_lnk); 259int GetStateOut(struct alias_link *_lnk); 260struct in_addr 261 GetOriginalAddress(struct alias_link *_lnk); 262struct in_addr 263 GetDestAddress(struct alias_link *_lnk); 264struct in_addr 265 GetAliasAddress(struct alias_link *_lnk); 266struct in_addr 267 GetDefaultAliasAddress(struct libalias *la); 268void SetDefaultAliasAddress(struct libalias *la, struct in_addr _alias_addr); 269u_short GetOriginalPort(struct alias_link *_lnk); 270u_short GetAliasPort(struct alias_link *_lnk); 271struct in_addr 272 GetProxyAddress(struct alias_link *_lnk); 273void SetProxyAddress(struct alias_link *_lnk, struct in_addr _addr); 274u_short GetProxyPort(struct alias_link *_lnk); 275void SetProxyPort(struct alias_link *_lnk, u_short _port); 276void SetAckModified(struct alias_link *_lnk); 277int GetAckModified(struct alias_link *_lnk); 278int GetDeltaAckIn(struct ip *_pip, struct alias_link *_lnk); 279int GetDeltaSeqOut(struct ip *_pip, struct alias_link *_lnk); 280void AddSeq (struct ip *_pip, struct alias_link *_lnk, int _delta); 281void SetExpire (struct alias_link *_lnk, int _expire); 282void ClearCheckNewLink(struct libalias *la); 283void SetProtocolFlags(struct alias_link *_lnk, int _pflags); 284int GetProtocolFlags(struct alias_link *_lnk); 285void SetDestCallId(struct alias_link *_lnk, u_int16_t _cid); 286 287#ifndef NO_FW_PUNCH 288void PunchFWHole(struct alias_link *_lnk); 289 290#endif 291 292/* Housekeeping function */ 293void HouseKeeping(struct libalias *); 294 295/* Tcp specfic routines */ 296/* lint -save -library Suppress flexelint warnings */ 297 298/* Transparent proxy routines */ 299int 300ProxyCheck(struct libalias *la, struct ip *_pip, struct in_addr *_proxy_server_addr, 301 u_short * _proxy_server_port); 302void 303ProxyModify(struct libalias *la, struct alias_link *_lnk, struct ip *_pip, 304 int _maxpacketsize, int _proxy_type); 305 306enum alias_tcp_state { 307 ALIAS_TCP_STATE_NOT_CONNECTED, 308 ALIAS_TCP_STATE_CONNECTED, 309 ALIAS_TCP_STATE_DISCONNECTED 310}; 311 312#if defined(_NETINET_IP_H_) 313static __inline void * 314ip_next(struct ip *iphdr) 315{ 316 char *p = (char *)iphdr; 317 return (&p[iphdr->ip_hl * 4]); 318} 319#endif 320 321#if defined(_NETINET_TCP_H_) 322static __inline void * 323tcp_next(struct tcphdr *tcphdr) 324{ 325 char *p = (char *)tcphdr; 326 return (&p[tcphdr->th_off * 4]); 327} 328#endif 329 330#if defined(_NETINET_UDP_H_) 331static __inline void * 332udp_next(struct udphdr *udphdr) 333{ 334 return ((void *)(udphdr + 1)); 335} 336#endif 337 338#endif /* !_ALIAS_LOCAL_H_ */ 339