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 * $FreeBSD$ 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 55 struct proxy_entry; 56 57 struct 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 */ 164 u_short IpChecksum(struct ip *_pip); 165 u_short TcpChecksum(struct ip *_pip); 166 void DifferentialChecksum(u_short *_cksum, u_short *_new, u_short *_old, 167 int _n); 168 169 /* Internal data access */ 170 struct alias_link * 171 FindIcmpIn(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 172 u_short _id_alias, int _create); 173 struct alias_link * 174 FindIcmpOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr, 175 u_short _id, int _create); 176 struct alias_link * 177 FindFragmentIn1(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 178 u_short _ip_id); 179 struct alias_link * 180 FindFragmentIn2(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 181 u_short _ip_id); 182 struct alias_link * 183 AddFragmentPtrLink(struct libalias *la, struct in_addr _dst_addr, u_short _ip_id); 184 struct alias_link * 185 FindFragmentPtr(struct libalias *la, struct in_addr _dst_addr, u_short _ip_id); 186 struct alias_link * 187 FindProtoIn(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 188 u_char _proto); 189 struct alias_link * 190 FindProtoOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr, 191 u_char _proto); 192 struct 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); 195 struct 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); 198 struct 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); 201 struct alias_link * 202 FindPptpOutByCallId(struct libalias *la, struct in_addr _src_addr, 203 struct in_addr _dst_addr, u_int16_t _src_call_id); 204 struct alias_link * 205 FindPptpInByCallId(struct libalias *la, struct in_addr _dst_addr, 206 struct in_addr _alias_addr, u_int16_t _dst_call_id); 207 struct alias_link * 208 FindPptpOutByPeerCallId(struct libalias *la, struct in_addr _src_addr, 209 struct in_addr _dst_addr, u_int16_t _dst_call_id); 210 struct alias_link * 211 FindPptpInByPeerCallId(struct libalias *la, struct in_addr _dst_addr, 212 struct in_addr _alias_addr, u_int16_t _alias_call_id); 213 struct 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); 216 struct in_addr 217 FindOriginalAddress(struct libalias *la, struct in_addr _alias_addr); 218 struct in_addr 219 FindAliasAddress(struct libalias *la, struct in_addr _original_addr); 220 221 /* External data access/modification */ 222 int 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); 225 void GetFragmentAddr(struct alias_link *_link, struct in_addr *_src_addr); 226 void SetFragmentAddr(struct alias_link *_link, struct in_addr _src_addr); 227 void GetFragmentPtr(struct alias_link *_link, char **_fptr); 228 void SetFragmentPtr(struct alias_link *_link, char *fptr); 229 void SetStateIn(struct alias_link *_link, int _state); 230 void SetStateOut(struct alias_link *_link, int _state); 231 int GetStateIn(struct alias_link *_link); 232 int GetStateOut(struct alias_link *_link); 233 struct in_addr 234 GetOriginalAddress(struct alias_link *_link); 235 struct in_addr 236 GetDestAddress(struct alias_link *_link); 237 struct in_addr 238 GetAliasAddress(struct alias_link *_link); 239 struct in_addr 240 GetDefaultAliasAddress(struct libalias *la); 241 void SetDefaultAliasAddress(struct libalias *la, struct in_addr _alias_addr); 242 u_short GetOriginalPort(struct alias_link *_link); 243 u_short GetAliasPort(struct alias_link *_link); 244 struct in_addr 245 GetProxyAddress(struct alias_link *_link); 246 void SetProxyAddress(struct alias_link *_link, struct in_addr _addr); 247 u_short GetProxyPort(struct alias_link *_link); 248 void SetProxyPort(struct alias_link *_link, u_short _port); 249 void SetAckModified(struct alias_link *_link); 250 int GetAckModified(struct alias_link *_link); 251 int GetDeltaAckIn(struct ip *_pip, struct alias_link *_link); 252 int GetDeltaSeqOut(struct ip *_pip, struct alias_link *_link); 253 void AddSeq(struct ip *_pip, struct alias_link *_link, int _delta); 254 void SetExpire(struct alias_link *_link, int _expire); 255 void ClearCheckNewLink(struct libalias *la); 256 void SetProtocolFlags(struct alias_link *_link, int _pflags); 257 int GetProtocolFlags(struct alias_link *_link); 258 void SetDestCallId(struct alias_link *_link, u_int16_t _cid); 259 #ifndef NO_FW_PUNCH 260 void PunchFWHole(struct alias_link *_link); 261 #endif 262 263 /* Housekeeping function */ 264 void HouseKeeping(struct libalias *); 265 266 /* Tcp specfic routines */ 267 /* lint -save -library Suppress flexelint warnings */ 268 269 /* FTP routines */ 270 void AliasHandleFtpOut(struct libalias *la, struct ip *_pip, struct alias_link *_link, 271 int _maxpacketsize); 272 273 /* IRC routines */ 274 void AliasHandleIrcOut(struct libalias *la, struct ip *_pip, struct alias_link *_link, 275 int _maxsize); 276 277 /* RTSP routines */ 278 void AliasHandleRtspOut(struct libalias *la, struct ip *_pip, struct alias_link *_link, 279 int _maxpacketsize); 280 281 /* PPTP routines */ 282 void AliasHandlePptpOut(struct libalias *la, struct ip *_pip, struct alias_link *_link); 283 void AliasHandlePptpIn(struct libalias *la, struct ip *_pip, struct alias_link *_link); 284 int AliasHandlePptpGreOut(struct libalias *la, struct ip *_pip); 285 int AliasHandlePptpGreIn(struct libalias *la, struct ip *_pip); 286 287 /* NetBIOS routines */ 288 int AliasHandleUdpNbt(struct libalias *la, struct ip *_pip, struct alias_link *_link, 289 struct in_addr *_alias_address, u_short _alias_port); 290 int 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 */ 295 void AliasHandleCUSeeMeOut(struct libalias *la, struct ip *_pip, struct alias_link *_link); 296 void AliasHandleCUSeeMeIn(struct libalias *la, struct ip *_pip, struct in_addr _original_addr); 297 298 /* Skinny routines */ 299 void AliasHandleSkinny(struct libalias *la, struct ip *_pip, struct alias_link *_link); 300 301 /* Transparent proxy routines */ 302 int ProxyCheck(struct libalias *la, struct ip *_pip, struct in_addr *_proxy_server_addr, 303 u_short *_proxy_server_port); 304 void ProxyModify(struct libalias *la, struct alias_link *_link, struct ip *_pip, 305 int _maxpacketsize, int _proxy_type); 306 307 enum 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