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 /* 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) 57 #endif 58 59 /* XXX: LibAliasSetTarget() uses this constant. */ 60 #ifdef _KERNEL 61 #define INADDR_NONE 0xffffffff 62 #endif 63 64 /* Sizes of input and output link tables */ 65 #define LINK_TABLE_OUT_SIZE 101 66 #define LINK_TABLE_IN_SIZE 4001 67 68 struct proxy_entry; 69 70 struct libalias { 71 LIST_ENTRY(libalias) instancelist; 72 73 int packetAliasMode; /* Mode flags */ 74 /* - documented in alias.h */ 75 76 struct in_addr aliasAddress; /* Address written onto source */ 77 /* field of IP packet. */ 78 79 struct in_addr targetAddress; /* IP address incoming packets */ 80 /* are sent to if no aliasing */ 81 /* link already exists */ 82 83 struct in_addr nullAddress; /* Used as a dummy parameter for */ 84 /* some function calls */ 85 86 LIST_HEAD (, alias_link) linkTableOut[LINK_TABLE_OUT_SIZE]; 87 /* Lookup table of pointers to */ 88 /* chains of link records. Each */ 89 90 LIST_HEAD (, alias_link) linkTableIn[LINK_TABLE_IN_SIZE]; 91 /* link record is doubly indexed */ 92 /* into input and output lookup */ 93 /* tables. */ 94 95 /* Link statistics */ 96 int icmpLinkCount; 97 int udpLinkCount; 98 int tcpLinkCount; 99 int pptpLinkCount; 100 int protoLinkCount; 101 int fragmentIdLinkCount; 102 int fragmentPtrLinkCount; 103 int sockCount; 104 105 int cleanupIndex; /* Index to chain of link table */ 106 /* being inspected for old links */ 107 108 int timeStamp; /* System time in seconds for */ 109 /* current packet */ 110 111 int lastCleanupTime; /* Last time 112 * IncrementalCleanup() */ 113 /* was called */ 114 115 int houseKeepingResidual; /* used by HouseKeeping() */ 116 117 int deleteAllLinks; /* If equal to zero, DeleteLink() */ 118 /* will not remove permanent links */ 119 #ifndef NO_LOGGING 120 FILE *monitorFile; /* File descriptor for link */ 121 #endif 122 /* statistics monitoring file */ 123 124 int newDefaultLink; /* Indicates if a new aliasing */ 125 /* link has been created after a */ 126 /* call to PacketAliasIn/Out(). */ 127 128 #ifndef NO_FW_PUNCH 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 */ 133 /* flag. */ 134 int fireWallBaseNum; /* The first firewall entry 135 * free for our use */ 136 int fireWallNumNums; /* How many entries can we 137 * use? */ 138 int fireWallActiveNum; /* Which entry did we last 139 * use? */ 140 char *fireWallField; /* bool array for entries */ 141 #endif 142 143 unsigned int skinnyPort; /* TCP port used by the Skinny */ 144 /* protocol. */ 145 146 struct proxy_entry *proxyList; 147 148 struct in_addr true_addr; /* in network byte order. */ 149 u_short true_port; /* in host byte order. */ 150 151 }; 152 153 /* Macros */ 154 155 /* 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. 162 */ 163 #define ADJUST_CHECKSUM(acc, cksum) \ 164 do { \ 165 acc += cksum; \ 166 if (acc < 0) { \ 167 acc = -acc; \ 168 acc = (acc >> 16) + (acc & 0xffff); \ 169 acc += acc >> 16; \ 170 cksum = (u_short) ~acc; \ 171 } else { \ 172 acc = (acc >> 16) + (acc & 0xffff); \ 173 acc += acc >> 16; \ 174 cksum = (u_short) acc; \ 175 } \ 176 } while (0) 177 178 179 /* Prototypes */ 180 181 /* General utilities */ 182 u_short IpChecksum(struct ip *_pip); 183 u_short TcpChecksum(struct ip *_pip); 184 void 185 DifferentialChecksum(u_short * _cksum, void * _new, void * _old, int _n); 186 187 /* Internal data access */ 188 struct alias_link * 189 FindIcmpIn(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 190 u_short _id_alias, int _create); 191 struct alias_link * 192 FindIcmpOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr, 193 u_short _id, int _create); 194 struct alias_link * 195 FindFragmentIn1(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 196 u_short _ip_id); 197 struct alias_link * 198 FindFragmentIn2(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 199 u_short _ip_id); 200 struct alias_link * 201 AddFragmentPtrLink(struct libalias *la, struct in_addr _dst_addr, u_short _ip_id); 202 struct alias_link * 203 FindFragmentPtr(struct libalias *la, struct in_addr _dst_addr, u_short _ip_id); 204 struct alias_link * 205 FindProtoIn(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 206 u_char _proto); 207 struct alias_link * 208 FindProtoOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr, 209 u_char _proto); 210 struct alias_link * 211 FindUdpTcpIn(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 212 u_short _dst_port, u_short _alias_port, u_char _proto, int _create); 213 struct alias_link * 214 FindUdpTcpOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr, 215 u_short _src_port, u_short _dst_port, u_char _proto, int _create); 216 struct alias_link * 217 AddPptp(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr, 218 struct in_addr _alias_addr, u_int16_t _src_call_id); 219 struct alias_link * 220 FindPptpOutByCallId(struct libalias *la, struct in_addr _src_addr, 221 struct in_addr _dst_addr, u_int16_t _src_call_id); 222 struct alias_link * 223 FindPptpInByCallId(struct libalias *la, struct in_addr _dst_addr, 224 struct in_addr _alias_addr, u_int16_t _dst_call_id); 225 struct alias_link * 226 FindPptpOutByPeerCallId(struct libalias *la, struct in_addr _src_addr, 227 struct in_addr _dst_addr, u_int16_t _dst_call_id); 228 struct alias_link * 229 FindPptpInByPeerCallId(struct libalias *la, struct in_addr _dst_addr, 230 struct in_addr _alias_addr, u_int16_t _alias_call_id); 231 struct alias_link * 232 FindRtspOut(struct libalias *la, struct in_addr _src_addr, struct in_addr _dst_addr, 233 u_short _src_port, u_short _alias_port, u_char _proto); 234 struct in_addr 235 FindOriginalAddress(struct libalias *la, struct in_addr _alias_addr); 236 struct in_addr 237 FindAliasAddress(struct libalias *la, struct in_addr _original_addr); 238 239 /* External data access/modification */ 240 int 241 FindNewPortGroup(struct libalias *la, struct in_addr _dst_addr, struct in_addr _alias_addr, 242 u_short _src_port, u_short _dst_port, u_short _port_count, 243 u_char _proto, u_char _align); 244 void GetFragmentAddr(struct alias_link *_lnk, struct in_addr *_src_addr); 245 void SetFragmentAddr(struct alias_link *_lnk, struct in_addr _src_addr); 246 void GetFragmentPtr(struct alias_link *_lnk, char **_fptr); 247 void SetFragmentPtr(struct alias_link *_lnk, char *fptr); 248 void SetStateIn(struct alias_link *_lnk, int _state); 249 void SetStateOut(struct alias_link *_lnk, int _state); 250 int GetStateIn (struct alias_link *_lnk); 251 int GetStateOut(struct alias_link *_lnk); 252 struct in_addr 253 GetOriginalAddress(struct alias_link *_lnk); 254 struct in_addr 255 GetDestAddress(struct alias_link *_lnk); 256 struct in_addr 257 GetAliasAddress(struct alias_link *_lnk); 258 struct in_addr 259 GetDefaultAliasAddress(struct libalias *la); 260 void SetDefaultAliasAddress(struct libalias *la, struct in_addr _alias_addr); 261 u_short GetOriginalPort(struct alias_link *_lnk); 262 u_short GetAliasPort(struct alias_link *_lnk); 263 struct in_addr 264 GetProxyAddress(struct alias_link *_lnk); 265 void SetProxyAddress(struct alias_link *_lnk, struct in_addr _addr); 266 u_short GetProxyPort(struct alias_link *_lnk); 267 void SetProxyPort(struct alias_link *_lnk, u_short _port); 268 void SetAckModified(struct alias_link *_lnk); 269 int GetAckModified(struct alias_link *_lnk); 270 int GetDeltaAckIn(struct ip *_pip, struct alias_link *_lnk); 271 int GetDeltaSeqOut(struct ip *_pip, struct alias_link *_lnk); 272 void AddSeq (struct ip *_pip, struct alias_link *_lnk, int _delta); 273 void SetExpire (struct alias_link *_lnk, int _expire); 274 void ClearCheckNewLink(struct libalias *la); 275 void SetProtocolFlags(struct alias_link *_lnk, int _pflags); 276 int GetProtocolFlags(struct alias_link *_lnk); 277 void SetDestCallId(struct alias_link *_lnk, u_int16_t _cid); 278 279 #ifndef NO_FW_PUNCH 280 void PunchFWHole(struct alias_link *_lnk); 281 282 #endif 283 284 /* Housekeeping function */ 285 void HouseKeeping(struct libalias *); 286 287 /* Tcp specfic routines */ 288 /* lint -save -library Suppress flexelint warnings */ 289 290 /* FTP routines */ 291 void 292 AliasHandleFtpOut(struct libalias *la, struct ip *_pip, struct alias_link *_lnk, 293 int _maxpacketsize); 294 295 /* IRC routines */ 296 void 297 AliasHandleIrcOut(struct libalias *la, struct ip *_pip, struct alias_link *_lnk, 298 int _maxsize); 299 300 /* RTSP routines */ 301 void 302 AliasHandleRtspOut(struct libalias *la, struct ip *_pip, struct alias_link *_lnk, 303 int _maxpacketsize); 304 305 /* PPTP routines */ 306 void AliasHandlePptpOut(struct libalias *la, struct ip *_pip, struct alias_link *_lnk); 307 void AliasHandlePptpIn(struct libalias *la, struct ip *_pip, struct alias_link *_lnk); 308 int AliasHandlePptpGreOut(struct libalias *la, struct ip *_pip); 309 int AliasHandlePptpGreIn(struct libalias *la, struct ip *_pip); 310 311 /* NetBIOS routines */ 312 int 313 AliasHandleUdpNbt(struct libalias *la, struct ip *_pip, struct alias_link *_lnk, 314 struct in_addr *_alias_address, u_short _alias_port); 315 int 316 AliasHandleUdpNbtNS(struct libalias *la, struct ip *_pip, struct alias_link *_lnk, 317 struct in_addr *_alias_address, u_short * _alias_port, 318 struct in_addr *_original_address, u_short * _original_port); 319 320 /* CUSeeMe routines */ 321 void AliasHandleCUSeeMeOut(struct libalias *la, struct ip *_pip, struct alias_link *_lnk); 322 void AliasHandleCUSeeMeIn(struct libalias *la, struct ip *_pip, struct in_addr _original_addr); 323 324 /* Skinny routines */ 325 void AliasHandleSkinny(struct libalias *la, struct ip *_pip, struct alias_link *_lnk); 326 327 /* Transparent proxy routines */ 328 int 329 ProxyCheck(struct libalias *la, struct ip *_pip, struct in_addr *_proxy_server_addr, 330 u_short * _proxy_server_port); 331 void 332 ProxyModify(struct libalias *la, struct alias_link *_lnk, struct ip *_pip, 333 int _maxpacketsize, int _proxy_type); 334 335 enum alias_tcp_state { 336 ALIAS_TCP_STATE_NOT_CONNECTED, 337 ALIAS_TCP_STATE_CONNECTED, 338 ALIAS_TCP_STATE_DISCONNECTED 339 }; 340 341 #if defined(_NETINET_IP_H_) 342 static __inline void * 343 ip_next(struct ip *iphdr) 344 { 345 char *p = (char *)iphdr; 346 return (&p[iphdr->ip_hl * 4]); 347 } 348 #endif 349 350 #if defined(_NETINET_TCP_H_) 351 static __inline void * 352 tcp_next(struct tcphdr *tcphdr) 353 { 354 char *p = (char *)tcphdr; 355 return (&p[tcphdr->th_off * 4]); 356 } 357 #endif 358 359 #if defined(_NETINET_UDP_H_) 360 static __inline void * 361 udp_next(struct udphdr *udphdr) 362 { 363 return ((void *)(udphdr + 1)); 364 } 365 #endif 366 367 /*lint -restore */ 368 369 #endif /* !_ALIAS_LOCAL_H_ */ 370