diff options
Diffstat (limited to 'lib/libalias/alias_cuseeme.c')
| -rw-r--r-- | lib/libalias/alias_cuseeme.c | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/lib/libalias/alias_cuseeme.c b/lib/libalias/alias_cuseeme.c new file mode 100644 index 0000000..b1b95f4 --- /dev/null +++ b/lib/libalias/alias_cuseeme.c @@ -0,0 +1,120 @@ +/*- + * 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. + * + * $FreeBSD$ + */ + +#include <sys/types.h> +#include <netinet/in_systm.h> +#include <netinet/in.h> +#include <netinet/ip.h> +#include <netinet/udp.h> + +#include "alias_local.h" + +/* 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 */ +}; + +void +AliasHandleCUSeeMeOut(struct ip *pip, struct alias_link *link) +{ + struct udphdr *ud; + + ud = (struct udphdr *)((char *)pip + (pip->ip_hl << 2)); + if(ud->uh_ulen >= sizeof(struct cu_header)) { + struct cu_header *cu; + struct alias_link *cu_link; + + cu = (struct cu_header *)(ud + 1); + if (cu->addr) + cu->addr = (u_int32_t)GetAliasAddress(link).s_addr; + + cu_link = FindUdpTcpOut(pip->ip_src, GetDestAddress(link), + ud->uh_dport, 0, IPPROTO_UDP); + +#ifndef NO_FW_PUNCH + if (cu_link) + PunchFWHole(cu_link); +#endif + } +} + +void +AliasHandleCUSeeMeIn(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; + + alias_addr.s_addr = pip->ip_dst.s_addr; + ud = (struct udphdr *)((char *)pip + (pip->ip_hl << 2)); + cu = (struct cu_header *)(ud + 1); + oc = (struct oc_header *)(cu + 1); + ci = (struct client_info *)(oc + 1); + end = (char *)cu + 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; + } + } +} |
