/* Unix SMB/CIFS implementation. NBT interface handling Copyright (C) Andrew Tridgell 2005 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "includes.h" #include "dlinklist.h" #include "nbt_server/nbt_server.h" #include "smbd/service_task.h" #include "lib/socket/socket.h" /* receive an incoming request and dispatch it to the right place */ static void nbtd_request_handler(struct nbt_name_socket *nbtsock, struct nbt_name_packet *packet, const struct nbt_peer_socket *src) { struct nbtd_interface *iface = talloc_get_type(nbtsock->incoming.private, struct nbtd_interface); struct nbtd_server *nbtsrv = iface->nbtsrv; nbtsrv->stats.total_received++; /* see if its from one of our own interfaces - if so, then ignore it */ if (nbtd_self_packet(nbtsock, packet, src)) { DEBUG(10,("Ignoring self packet from %s:%d\n", src->addr, src->port)); return; } switch (packet->operation & NBT_OPCODE) { case NBT_OPCODE_QUERY: nbtsrv->stats.query_count++; nbtd_request_query(nbtsock, packet, src); break; case NBT_OPCODE_REGISTER: case NBT_OPCODE_REFRESH: case NBT_OPCODE_REFRESH2: nbtsrv->stats.register_count++; nbtd_request_defense(nbtsock, packet, src); break; case NBT_OPCODE_RELEASE: case NBT_OPCODE_MULTI_HOME_REG: nbtsrv->stats.release_count++; nbtd_winsserver_request(nbtsock, packet, src); break; default: nbtd_bad_packet(packet, src, "Unexpected opcode"); break; } } /* find a registered name on an interface */ struct nbtd_iface_name *nbtd_find_iname(struct nbtd_interface *iface, struct nbt_name *name, uint16_t nb_flags) { struct nbtd_iface_name *iname; for (iname=iface->names;iname;iname=iname->next) { if (iname->name.type == name->type && strcmp(name->name, iname->name.name) == 0 && ((iname->nb_flags & nb_flags) == nb_flags)) { return iname; } } return NULL; } /* start listening on the given address */ static NTSTATUS nbtd_add_socket(struct nbtd_server *nbtsrv, const char *bind_address, const char *address, const char *bcast, const char *netmask) { struct nbtd_interface *iface; NTSTATUS status; /* we actually create two sockets. One listens on the broadcast address for the interface, and the other listens on our specific address. This allows us to run with "bind interfaces only" while still receiving broadcast addresses, and also simplifies matching incoming requests to interfaces */ iface = talloc(nbtsrv, struct nbtd_interface); NT_STATUS_HAVE_NO_MEMORY(iface); iface->nbtsrv = nbtsrv; iface->bcast_address = talloc_steal(iface, bcast); iface->ip_address = talloc_steal(iface, address); iface->netmask = talloc_steal(iface, netmask); iface->names = NULL; if (strcmp(netmask, "0.0.0.0") != 0) { struct nbt_name_socket *bcast_nbtsock; /* listen for broadcasts on port 137 */ bcast_nbtsock = nbt_name_socket_init(iface, nbtsrv->task->event_ctx); NT_STATUS_HAVE_NO_MEMORY(bcast_nbtsock); status = socket_listen(bcast_nbtsock->sock, bcast, lp_nbt_port(), 0, 0); if (!NT_STATUS_IS_OK(status)) { DEBUG(0,("Failed to bind to %s:%d - %s\n", bcast, lp_nbt_port(), nt_errstr(status))); talloc_free(iface); return status; } nbt_set_incoming_handler(bcast_nbtsock, nbtd_request_handler, iface); } /* listen for unicasts on port 137 */ iface->nbtsock = nbt_name_socket_init(iface, nbtsrv->task->event_ctx); NT_STATUS_HAVE_NO_MEMORY(iface->nbtsock); status = socket_listen(iface->nbtsock->sock, bind_address, lp_nbt_port(), 0, 0); if (!NT_STATUS_IS_OK(status)) { DEBUG(0,("Failed to bind to %s:%d - %s\n", bind_address, lp_nbt_port(), nt_errstr(status))); talloc_free(iface); return status; } nbt_set_incoming_handler(iface->nbtsock, nbtd_request_handler, iface); /* also setup the datagram listeners */ status = nbtd_dgram_setup(iface, bind_address); if (!NT_STATUS_IS_OK(status)) { DEBUG(0,("Failed to setup dgram listen on %s - %s\n", bind_address, nt_errstr(status))); talloc_free(iface); return status; } if (strcmp(netmask, "0.0.0.0") == 0) { DLIST_ADD(nbtsrv->bcast_interface, iface); } else { DLIST_ADD(nbtsrv->interfaces, iface); } return NT_STATUS_OK; } /* setup a socket for talking to our WINS servers */ static NTSTATUS nbtd_add_wins_socket(struct nbtd_server *nbtsrv) { struct nbtd_interface *iface; iface = talloc_zero(nbtsrv, struct nbtd_interface); NT_STATUS_HAVE_NO_MEMORY(iface); iface->nbtsrv = nbtsrv; DLIST_ADD(nbtsrv->wins_interface, iface); return NT_STATUS_OK; } /* setup our listening sockets on the configured network interfaces */ NTSTATUS nbtd_startup_interfaces(struct nbtd_server *nbtsrv) { int num_interfaces = iface_count(); int i; TALLOC_CTX *tmp_ctx = talloc_new(nbtsrv); NTSTATUS status; /* if we are allowing incoming packets from any address, then we also need to bind to the wildcard address */ if (!lp_bind_interfaces_only()) { const char *primary_address; /* the primary address is the address we will return for non-WINS queries not made on a specific interface */ if (num_interfaces > 0) { primary_address = iface_n_ip(0); } else { primary_address = sys_inet_ntoa(interpret_addr2( lp_netbios_name())); } primary_address = talloc_strdup(tmp_ctx, primary_address); NT_STATUS_HAVE_NO_MEMORY(primary_address); status = nbtd_add_socket(nbtsrv, "0.0.0.0", primary_address, talloc_strdup(tmp_ctx, "255.255.255.255"), talloc_strdup(tmp_ctx, "0.0.0.0")); NT_STATUS_NOT_OK_RETURN(status); } for (i=0; inbtsrv; const char **ret = NULL; struct nbtd_interface *iface2; if (iface->ip_address) { ret = str_list_add(ret, iface->ip_address); } for (iface2=nbtsrv->interfaces;iface2;iface2=iface2->next) { if (iface->ip_address && strcmp(iface2->ip_address, iface->ip_address) == 0) { continue; } ret = str_list_add(ret, iface2->ip_address); } talloc_steal(mem_ctx, ret); /* if the query didn't come from loopback, then never give out loopback in the reply, as loopback means something different for the recipient than for us */ if (ret != NULL && iface->ip_address != NULL && strcmp(iface->ip_address, "127.0.0.1") != 0) { str_list_remove(ret, "127.0.0.1"); } return ret; } /* find the interface to use for sending a outgoing request */ struct nbtd_interface *nbtd_find_interface(struct nbtd_server *nbtd_server, const char *address) { struct nbtd_interface *iface; /* try to find a exact match */ for (iface=nbtd_server->interfaces;iface;iface=iface->next) { if (iface_same_net(address, iface->ip_address, iface->netmask)) { return iface; } } /* no exact match, if we have the broadcast interface, use that */ if (nbtd_server->bcast_interface) { return nbtd_server->bcast_interface; } /* fallback to first interface */ return nbtd_server->interfaces; }