13b160b8bSBrian Somers /* lint -save -library Flexelint comment for external headers */ 23b160b8bSBrian Somers 371593f95SBrian Somers /*- 4e83aaae3SBrian Somers * Copyright (c) 2001 Charles Mott <cm@linktel.net> 5f987e1bdSBrian Somers * All rights reserved. 6f987e1bdSBrian Somers * 7f987e1bdSBrian Somers * Redistribution and use in source and binary forms, with or without 8f987e1bdSBrian Somers * modification, are permitted provided that the following conditions 9f987e1bdSBrian Somers * are met: 10f987e1bdSBrian Somers * 1. Redistributions of source code must retain the above copyright 11f987e1bdSBrian Somers * notice, this list of conditions and the following disclaimer. 12f987e1bdSBrian Somers * 2. Redistributions in binary form must reproduce the above copyright 13f987e1bdSBrian Somers * notice, this list of conditions and the following disclaimer in the 14f987e1bdSBrian Somers * documentation and/or other materials provided with the distribution. 15f987e1bdSBrian Somers * 16f987e1bdSBrian Somers * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17f987e1bdSBrian Somers * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18f987e1bdSBrian Somers * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19f987e1bdSBrian Somers * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20f987e1bdSBrian Somers * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21f987e1bdSBrian Somers * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22f987e1bdSBrian Somers * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23f987e1bdSBrian Somers * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24f987e1bdSBrian Somers * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25f987e1bdSBrian Somers * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26f987e1bdSBrian Somers * SUCH DAMAGE. 27f987e1bdSBrian Somers * 28f987e1bdSBrian Somers * $FreeBSD$ 29f987e1bdSBrian Somers */ 30f987e1bdSBrian Somers 31be4f3cd0SPaolo Pisati /* 3271593f95SBrian Somers * Alias.h defines the outside world interfaces for the packet aliasing 3371593f95SBrian Somers * software. 3471593f95SBrian Somers * 3571593f95SBrian Somers * This software is placed into the public domain with no restrictions on its 3671593f95SBrian Somers * distribution. 373b160b8bSBrian Somers */ 383b160b8bSBrian Somers 393b160b8bSBrian Somers #ifndef _ALIAS_H_ 403b160b8bSBrian Somers #define _ALIAS_H_ 413b160b8bSBrian Somers 42be4f3cd0SPaolo Pisati #include <netinet/in_systm.h> 43be4f3cd0SPaolo Pisati #include <netinet/in.h> 44be4f3cd0SPaolo Pisati #include <netinet/ip.h> 45be4f3cd0SPaolo Pisati 46be4f3cd0SPaolo Pisati #define LIBALIAS_BUF_SIZE 128 47f87fe393SGleb Smirnoff #ifdef _KERNEL 48f87fe393SGleb Smirnoff /* 49f87fe393SGleb Smirnoff * The kernel version of libalias does not support these features. 50f87fe393SGleb Smirnoff */ 51f87fe393SGleb Smirnoff #define NO_FW_PUNCH 52f87fe393SGleb Smirnoff #define NO_USE_SOCKETS 53f87fe393SGleb Smirnoff #endif 54f87fe393SGleb Smirnoff 555e289f9eSPoul-Henning Kamp /* 565e289f9eSPoul-Henning Kamp * The external interface to libalias, the packet aliasing engine. 575e289f9eSPoul-Henning Kamp * 585e289f9eSPoul-Henning Kamp * There are two sets of functions: 595e289f9eSPoul-Henning Kamp * 605e289f9eSPoul-Henning Kamp * PacketAlias*() the old API which doesn't take an instance pointer 615e289f9eSPoul-Henning Kamp * and therefore can only have one packet engine at a time. 625e289f9eSPoul-Henning Kamp * 635e289f9eSPoul-Henning Kamp * LibAlias*() the new API which takes as first argument a pointer to 645e289f9eSPoul-Henning Kamp * the instance of the packet aliasing engine. 655e289f9eSPoul-Henning Kamp * 665e289f9eSPoul-Henning Kamp * The functions otherwise correspond to each other one for one, except 675e289f9eSPoul-Henning Kamp * for the LibAliasUnaliasOut()/PacketUnaliasOut() function which were 685e289f9eSPoul-Henning Kamp * were misnamed in the old API. 695e289f9eSPoul-Henning Kamp */ 705e289f9eSPoul-Henning Kamp 715e289f9eSPoul-Henning Kamp /* 725e289f9eSPoul-Henning Kamp * The instance structure 735e289f9eSPoul-Henning Kamp */ 745e289f9eSPoul-Henning Kamp struct libalias; 755e289f9eSPoul-Henning Kamp 765e289f9eSPoul-Henning Kamp /* 775e289f9eSPoul-Henning Kamp * An anonymous structure, a pointer to which is returned from 785e289f9eSPoul-Henning Kamp * PacketAliasRedirectAddr(), PacketAliasRedirectPort() or 795e289f9eSPoul-Henning Kamp * PacketAliasRedirectProto(), passed to PacketAliasAddServer(), 805e289f9eSPoul-Henning Kamp * and freed by PacketAliasRedirectDelete(). 815e289f9eSPoul-Henning Kamp */ 825e289f9eSPoul-Henning Kamp struct alias_link; 835e289f9eSPoul-Henning Kamp 845e289f9eSPoul-Henning Kamp /* Initialization and control functions. */ 855e289f9eSPoul-Henning Kamp struct libalias *LibAliasInit(struct libalias *); 865e289f9eSPoul-Henning Kamp void LibAliasSetAddress(struct libalias *, struct in_addr _addr); 875e289f9eSPoul-Henning Kamp void LibAliasSetFWBase(struct libalias *, unsigned int _base, unsigned int _num); 885e289f9eSPoul-Henning Kamp void LibAliasSetSkinnyPort(struct libalias *, unsigned int _port); 895e289f9eSPoul-Henning Kamp unsigned int 905e289f9eSPoul-Henning Kamp LibAliasSetMode(struct libalias *, unsigned int _flags, unsigned int _mask); 915e289f9eSPoul-Henning Kamp void LibAliasUninit(struct libalias *); 925e289f9eSPoul-Henning Kamp 935e289f9eSPoul-Henning Kamp /* Packet Handling functions. */ 945e289f9eSPoul-Henning Kamp int LibAliasIn (struct libalias *, char *_ptr, int _maxpacketsize); 955e289f9eSPoul-Henning Kamp int LibAliasOut(struct libalias *, char *_ptr, int _maxpacketsize); 96e6bbb691SPoul-Henning Kamp int LibAliasOutTry(struct libalias *, char *_ptr, int _maxpacketsize, int _create); 975e289f9eSPoul-Henning Kamp int LibAliasUnaliasOut(struct libalias *, char *_ptr, int _maxpacketsize); 985e289f9eSPoul-Henning Kamp 995e289f9eSPoul-Henning Kamp /* Port and address redirection functions. */ 1005e289f9eSPoul-Henning Kamp 101f0f93429SDag-Erling Smørgrav int 102ed01a582SDag-Erling Smørgrav LibAliasAddServer(struct libalias *, struct alias_link *_lnk, 1035e289f9eSPoul-Henning Kamp struct in_addr _addr, unsigned short _port); 1045e289f9eSPoul-Henning Kamp struct alias_link * 1055e289f9eSPoul-Henning Kamp LibAliasRedirectAddr(struct libalias *, struct in_addr _src_addr, 1065e289f9eSPoul-Henning Kamp struct in_addr _alias_addr); 107ed01a582SDag-Erling Smørgrav int LibAliasRedirectDynamic(struct libalias *, struct alias_link *_lnk); 108ed01a582SDag-Erling Smørgrav void LibAliasRedirectDelete(struct libalias *, struct alias_link *_lnk); 1095e289f9eSPoul-Henning Kamp struct alias_link * 1105e289f9eSPoul-Henning Kamp LibAliasRedirectPort(struct libalias *, struct in_addr _src_addr, 1115e289f9eSPoul-Henning Kamp unsigned short _src_port, struct in_addr _dst_addr, 1125e289f9eSPoul-Henning Kamp unsigned short _dst_port, struct in_addr _alias_addr, 1135e289f9eSPoul-Henning Kamp unsigned short _alias_port, unsigned char _proto); 1145e289f9eSPoul-Henning Kamp struct alias_link * 1155e289f9eSPoul-Henning Kamp LibAliasRedirectProto(struct libalias *, struct in_addr _src_addr, 1165e289f9eSPoul-Henning Kamp struct in_addr _dst_addr, struct in_addr _alias_addr, 1175e289f9eSPoul-Henning Kamp unsigned char _proto); 1185e289f9eSPoul-Henning Kamp 1195e289f9eSPoul-Henning Kamp /* Fragment Handling functions. */ 1205e289f9eSPoul-Henning Kamp void LibAliasFragmentIn(struct libalias *, char *_ptr, char *_ptr_fragment); 1215e289f9eSPoul-Henning Kamp char *LibAliasGetFragment(struct libalias *, char *_ptr); 1225e289f9eSPoul-Henning Kamp int LibAliasSaveFragment(struct libalias *, char *_ptr); 1235e289f9eSPoul-Henning Kamp 1245e289f9eSPoul-Henning Kamp /* Miscellaneous functions. */ 1255e289f9eSPoul-Henning Kamp int LibAliasCheckNewLink(struct libalias *); 1265e289f9eSPoul-Henning Kamp unsigned short 1275e289f9eSPoul-Henning Kamp LibAliasInternetChecksum(struct libalias *, unsigned short *_ptr, int _nbytes); 1285e289f9eSPoul-Henning Kamp void LibAliasSetTarget(struct libalias *, struct in_addr _target_addr); 1295e289f9eSPoul-Henning Kamp 1305e289f9eSPoul-Henning Kamp /* Transparent proxying routines. */ 1315e289f9eSPoul-Henning Kamp int LibAliasProxyRule(struct libalias *, const char *_cmd); 1325e289f9eSPoul-Henning Kamp 133be4f3cd0SPaolo Pisati /* Module handling API */ 134be4f3cd0SPaolo Pisati int LibAliasLoadModule(char *); 135be4f3cd0SPaolo Pisati int LibAliasUnLoadAllModule(void); 136be4f3cd0SPaolo Pisati int LibAliasRefreshModules(void); 1375e289f9eSPoul-Henning Kamp 138e876228eSPaolo Pisati /* Mbuf helper function. */ 139e876228eSPaolo Pisati struct mbuf *m_megapullup(struct mbuf *, int); 140e876228eSPaolo Pisati 1415e289f9eSPoul-Henning Kamp /* 1425e289f9eSPoul-Henning Kamp * Mode flags and other constants. 1435e289f9eSPoul-Henning Kamp */ 1445e289f9eSPoul-Henning Kamp 1455e289f9eSPoul-Henning Kamp 14671593f95SBrian Somers /* Mode flags, set using PacketAliasSetMode() */ 1473efa11bbSBrian Somers 14871593f95SBrian Somers /* 14971593f95SBrian Somers * If PKT_ALIAS_LOG is set, a message will be printed to /var/log/alias.log 15071593f95SBrian Somers * every time a link is created or deleted. This is useful for debugging. 15171593f95SBrian Somers */ 1523efa11bbSBrian Somers #define PKT_ALIAS_LOG 0x01 1533b160b8bSBrian Somers 15471593f95SBrian Somers /* 15571593f95SBrian Somers * If PKT_ALIAS_DENY_INCOMING is set, then incoming connections (e.g. to ftp, 15671593f95SBrian Somers * telnet or web servers will be prevented by the aliasing mechanism. 15771593f95SBrian Somers */ 1583efa11bbSBrian Somers #define PKT_ALIAS_DENY_INCOMING 0x02 1593b160b8bSBrian Somers 16071593f95SBrian Somers /* 16171593f95SBrian Somers * If PKT_ALIAS_SAME_PORTS is set, packets will be attempted sent from the 16271593f95SBrian Somers * same port as they originated on. This allows e.g. rsh to work *99% of the 16371593f95SBrian Somers * time*, but _not_ 100% (it will be slightly flakey instead of not working 16471593f95SBrian Somers * at all). This mode bit is set by PacketAliasInit(), so it is a default 16571593f95SBrian Somers * mode of operation. 16671593f95SBrian Somers */ 1673efa11bbSBrian Somers #define PKT_ALIAS_SAME_PORTS 0x04 1683b160b8bSBrian Somers 16971593f95SBrian Somers /* 17071593f95SBrian Somers * If PKT_ALIAS_USE_SOCKETS is set, then when partially specified links (e.g. 17171593f95SBrian Somers * destination port and/or address is zero), the packet aliasing engine will 17271593f95SBrian Somers * attempt to allocate a socket for the aliasing port it chooses. This will 17371593f95SBrian Somers * avoid interference with the host machine. Fully specified links do not 17471593f95SBrian Somers * require this. This bit is set after a call to PacketAliasInit(), so it is 17571593f95SBrian Somers * a default mode of operation. 17671593f95SBrian Somers */ 17700fc9a5bSGleb Smirnoff #ifndef NO_USE_SOCKETS 1783efa11bbSBrian Somers #define PKT_ALIAS_USE_SOCKETS 0x08 17900fc9a5bSGleb Smirnoff #endif 18071593f95SBrian Somers /*- 18171593f95SBrian Somers * If PKT_ALIAS_UNREGISTERED_ONLY is set, then only packets with 18271593f95SBrian Somers * unregistered source addresses will be aliased. Private 18371593f95SBrian Somers * addresses are those in the following ranges: 18471593f95SBrian Somers * 18571593f95SBrian Somers * 10.0.0.0 -> 10.255.255.255 18671593f95SBrian Somers * 172.16.0.0 -> 172.31.255.255 18771593f95SBrian Somers * 192.168.0.0 -> 192.168.255.255 18871593f95SBrian Somers */ 1893efa11bbSBrian Somers #define PKT_ALIAS_UNREGISTERED_ONLY 0x10 1903b160b8bSBrian Somers 19171593f95SBrian Somers /* 19271593f95SBrian Somers * If PKT_ALIAS_RESET_ON_ADDR_CHANGE is set, then the table of dynamic 19371593f95SBrian Somers * aliasing links will be reset whenever PacketAliasSetAddress() changes the 19471593f95SBrian Somers * default aliasing address. If the default aliasing address is left 19571593f95SBrian Somers * unchanged by this function call, then the table of dynamic aliasing links 19671593f95SBrian Somers * will be left intact. This bit is set after a call to PacketAliasInit(). 19771593f95SBrian Somers */ 1983efa11bbSBrian Somers #define PKT_ALIAS_RESET_ON_ADDR_CHANGE 0x20 1993b160b8bSBrian Somers 20071593f95SBrian Somers /* 20171593f95SBrian Somers * If PKT_ALIAS_PROXY_ONLY is set, then NAT will be disabled and only 20271593f95SBrian Somers * transparent proxying is performed. 20371593f95SBrian Somers */ 2047d96f4efSBrian Somers #define PKT_ALIAS_PROXY_ONLY 0x40 2057d96f4efSBrian Somers 20671593f95SBrian Somers /* 20771593f95SBrian Somers * If PKT_ALIAS_REVERSE is set, the actions of PacketAliasIn() and 20871593f95SBrian Somers * PacketAliasOut() are reversed. 20971593f95SBrian Somers */ 2107d96f4efSBrian Somers #define PKT_ALIAS_REVERSE 0x80 2117d96f4efSBrian Somers 212*81a65464SAndrey V. Elsukov #ifndef NO_FW_PUNCH 213*81a65464SAndrey V. Elsukov /* 214*81a65464SAndrey V. Elsukov * If PKT_ALIAS_PUNCH_FW is set, active FTP and IRC DCC connections will 215*81a65464SAndrey V. Elsukov * create a 'hole' in the firewall to allow the transfers to work. The 216*81a65464SAndrey V. Elsukov * ipfw rule number that the hole is created with is controlled by 217*81a65464SAndrey V. Elsukov * PacketAliasSetFWBase(). The hole will be attached to that 218*81a65464SAndrey V. Elsukov * particular alias_link, so when the link goes away the hole is deleted. 219*81a65464SAndrey V. Elsukov */ 220*81a65464SAndrey V. Elsukov #define PKT_ALIAS_PUNCH_FW 0x100 221*81a65464SAndrey V. Elsukov #endif 222*81a65464SAndrey V. Elsukov 22371593f95SBrian Somers /* Function return codes. */ 2243b160b8bSBrian Somers #define PKT_ALIAS_ERROR -1 2253b160b8bSBrian Somers #define PKT_ALIAS_OK 1 2263b160b8bSBrian Somers #define PKT_ALIAS_IGNORED 2 2273b160b8bSBrian Somers #define PKT_ALIAS_UNRESOLVED_FRAGMENT 3 2283b160b8bSBrian Somers #define PKT_ALIAS_FOUND_HEADER_FRAGMENT 4 2293b160b8bSBrian Somers 23071593f95SBrian Somers #endif /* !_ALIAS_H_ */ 23171593f95SBrian Somers 2323b160b8bSBrian Somers /* lint -restore */ 233