Current Path : /sys/netinet/libalias/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
Current File : //sys/netinet/libalias/alias_cuseeme.c |
/*- * Copyright (c) 1998 Brian Somers <brian@Awfulhak.org> * with the aid of code written by * Junichi SATOH <junichi@astec.co.jp> 1996, 1997. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include <sys/cdefs.h> __FBSDID("$FreeBSD: release/9.1.0/sys/netinet/libalias/alias_cuseeme.c 190841 2009-04-08 11:56:49Z piso $"); #ifdef _KERNEL #include <sys/param.h> #include <sys/kernel.h> #include <sys/module.h> #else #include <errno.h> #include <sys/types.h> #include <stdio.h> #endif #include <netinet/in_systm.h> #include <netinet/in.h> #include <netinet/ip.h> #include <netinet/udp.h> #ifdef _KERNEL #include <netinet/libalias/alias.h> #include <netinet/libalias/alias_local.h> #include <netinet/libalias/alias_mod.h> #else #include "alias_local.h" #include "alias_mod.h" #endif #define CUSEEME_PORT_NUMBER 7648 static void AliasHandleCUSeeMeOut(struct libalias *la, struct ip *pip, struct alias_link *lnk); static void AliasHandleCUSeeMeIn(struct libalias *la, struct ip *pip, struct in_addr original_addr); static int fingerprint(struct libalias *la, struct alias_data *ah) { if (ah->dport == NULL || ah->oaddr == NULL) return (-1); if (ntohs(*ah->dport) == CUSEEME_PORT_NUMBER) return (0); return (-1); } static int protohandlerin(struct libalias *la, struct ip *pip, struct alias_data *ah) { AliasHandleCUSeeMeIn(la, pip, *ah->oaddr); return (0); } static int protohandlerout(struct libalias *la, struct ip *pip, struct alias_data *ah) { AliasHandleCUSeeMeOut(la, pip, ah->lnk); return (0); } /* Kernel module definition. */ struct proto_handler handlers[] = { { .pri = 120, .dir = OUT, .proto = UDP, .fingerprint = &fingerprint, .protohandler = &protohandlerout }, { .pri = 120, .dir = IN, .proto = UDP, .fingerprint = &fingerprint, .protohandler = &protohandlerin }, { EOH } }; static int mod_handler(module_t mod, int type, void *data) { int error; switch (type) { case MOD_LOAD: error = 0; LibAliasAttachHandlers(handlers); break; case MOD_UNLOAD: error = 0; LibAliasDetachHandlers(handlers); break; default: error = EINVAL; } return (error); } #ifdef _KERNEL static #endif moduledata_t alias_mod = { "alias_cuseeme", mod_handler, NULL }; #ifdef _KERNEL DECLARE_MODULE(alias_cuseeme, alias_mod, SI_SUB_DRIVERS, SI_ORDER_SECOND); MODULE_VERSION(alias_cuseeme, 1); MODULE_DEPEND(alias_cuseeme, libalias, 1, 1, 1); #endif /* CU-SeeMe Data Header */ struct cu_header { u_int16_t dest_family; u_int16_t dest_port; u_int32_t dest_addr; int16_t family; u_int16_t port; u_int32_t addr; u_int32_t seq; u_int16_t msg; u_int16_t data_type; u_int16_t packet_len; }; /* Open Continue Header */ struct oc_header { u_int16_t client_count; /* Number of client info structs */ u_int32_t seq_no; char user_name [20]; char reserved [4]; /* flags, version stuff, etc */ }; /* client info structures */ struct client_info { u_int32_t address;/* Client address */ char reserved [8]; /* Flags, pruning bitfield, packet * counts etc */ }; static void AliasHandleCUSeeMeOut(struct libalias *la, struct ip *pip, struct alias_link *lnk) { struct udphdr *ud = ip_next(pip); if (ntohs(ud->uh_ulen) - sizeof(struct udphdr) >= sizeof(struct cu_header)) { struct cu_header *cu; struct alias_link *cu_lnk; cu = udp_next(ud); if (cu->addr) cu->addr = (u_int32_t) GetAliasAddress(lnk).s_addr; cu_lnk = FindUdpTcpOut(la, pip->ip_src, GetDestAddress(lnk), ud->uh_dport, 0, IPPROTO_UDP, 1); #ifndef NO_FW_PUNCH if (cu_lnk) PunchFWHole(cu_lnk); #endif } } static void AliasHandleCUSeeMeIn(struct libalias *la, struct ip *pip, struct in_addr original_addr) { struct in_addr alias_addr; struct udphdr *ud; struct cu_header *cu; struct oc_header *oc; struct client_info *ci; char *end; int i; (void)la; alias_addr.s_addr = pip->ip_dst.s_addr; ud = ip_next(pip); cu = udp_next(ud); oc = (struct oc_header *)(cu + 1); ci = (struct client_info *)(oc + 1); end = (char *)ud + ntohs(ud->uh_ulen); if ((char *)oc <= end) { if (cu->dest_addr) cu->dest_addr = (u_int32_t) original_addr.s_addr; if (ntohs(cu->data_type) == 101) /* Find and change our address */ for (i = 0; (char *)(ci + 1) <= end && i < oc->client_count; i++, ci++) if (ci->address == (u_int32_t) alias_addr.s_addr) { ci->address = (u_int32_t) original_addr.s_addr; break; } } }