1 files changed, 426 insertions, 0 deletions

diff --git a/source4/nbt_server/interfaces.c b/source4/nbt_server/interfaces.c
new file mode 100644
index 0000000..93e1497
--- /dev/null
+++ b/source4/nbt_server/interfaces.c
@@ -0,0 +1,426 @@
+/* 
+   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 3 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, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "includes.h"
+#include "../lib/util/dlinklist.h"
+#include "nbt_server/nbt_server.h"
+#include "samba/service_task.h"
+#include "lib/socket/socket.h"
+#include "nbt_server/wins/winsserver.h"
+#include "nbt_server/dgram/proto.h"
+#include "system/network.h"
+#include "lib/socket/netif.h"
+#include "param/param.h"
+#include "lib/util/util_net.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, 
+				 struct socket_address *src)
+{
+	struct nbtd_interface *iface = talloc_get_type(nbtsock->incoming.private_data,
+						       struct nbtd_interface);
+	struct nbtd_server *nbtsrv = iface->nbtsrv;
+
+	nbtsrv->stats.total_received++;
+
+	/* see if it's from one of our own interfaces - if so, then ignore it */
+	if (nbtd_self_packet_and_bcast(nbtsock, packet, src)) {
+		DEBUG(10,("Ignoring bcast 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;
+	}
+}
+
+static void nbtd_unexpected_handler(struct nbt_name_socket *nbtsock,
+				    struct nbt_name_packet *packet,
+				    struct socket_address *src)
+{
+	struct nbtd_interface *iface = talloc_get_type(nbtsock->incoming.private_data,
+						       struct nbtd_interface);
+	struct nbtd_server *nbtsrv = iface->nbtsrv;
+	struct nbtd_interface *i;
+	struct nbt_name_request *req = NULL;
+
+	nbtsrv->stats.total_received++;
+
+	DEBUG(10,("unexpected from src[%s] on interface[%p] %s/%s\n",
+		src->addr, iface, iface->ip_address, iface->netmask));
+
+	/* try the broadcast interface */
+	if (nbtsrv->bcast_interface) {
+		i = nbtsrv->bcast_interface;
+		req = idr_find(i->nbtsock->idr, packet->name_trn_id);
+	}
+
+	/* try the wins server client interface */
+	if (!req && nbtsrv->wins_interface && nbtsrv->wins_interface->nbtsock) {
+		i = nbtsrv->wins_interface;
+		req = idr_find(i->nbtsock->idr, packet->name_trn_id);
+	}
+
+	/* try all other interfaces... */
+	if (!req) {
+		for (i = nbtsrv->interfaces; i; i = i->next) {
+			if (i == iface) {
+				continue;
+			}
+			req = idr_find(i->nbtsock->idr, packet->name_trn_id);
+			if (req) break;
+		}
+	}
+
+	if (!req) {
+		DEBUG(10,("unexpected from src[%s] unable to redirected\n", src->addr));
+		return;
+	}
+
+	DEBUG(10,("unexpected from src[%s] redirected to interface[%p] %s/%s\n",
+		src->addr, i, i->ip_address, i->netmask));
+
+	/*
+	 * redirect the incoming response to the socket
+	 * we sent the matching request
+	 */
+	nbt_name_socket_handle_response_packet(req, packet, src);
+}
+
+/*
+  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, 
+				struct loadparm_context *lp_ctx,
+				const char *bind_address, 
+				const char *address, 
+				const char *bcast, 
+				const char *netmask)
+{
+	struct nbtd_interface *iface;
+	NTSTATUS status;
+	struct socket_address *bcast_address;
+	struct socket_address *unicast_address;
+
+	DEBUG(6,("nbtd_add_socket(%s, %s, %s, %s)\n", bind_address, address, bcast, netmask));
+
+	/*
+	  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;
+	iface->wack_queue    = 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);
+		if (!bcast_nbtsock) {
+			talloc_free(iface);
+			return NT_STATUS_NO_MEMORY;
+		}
+
+		bcast_address = socket_address_from_strings(bcast_nbtsock, bcast_nbtsock->sock->backend_name, 
+							    bcast, lpcfg_nbt_port(lp_ctx));
+		if (!bcast_address) {
+			talloc_free(iface);
+			return NT_STATUS_NO_MEMORY;
+		}
+
+		status = socket_listen(bcast_nbtsock->sock, bcast_address, 0, 0);
+		if (!NT_STATUS_IS_OK(status)) {
+			DEBUG(0,("Failed to bind to %s:%d - %s\n", 
+				 bcast, lpcfg_nbt_port(lp_ctx), nt_errstr(status)));
+			talloc_free(iface);
+			return status;
+		}
+		talloc_free(bcast_address);
+
+		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);
+	if (!iface->nbtsock) {
+		talloc_free(iface);
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	unicast_address = socket_address_from_strings(iface->nbtsock, 
+						      iface->nbtsock->sock->backend_name, 
+						      bind_address, lpcfg_nbt_port(lp_ctx));
+
+	status = socket_listen(iface->nbtsock->sock, unicast_address, 0, 0);
+	if (!NT_STATUS_IS_OK(status)) {
+		DEBUG(0,("Failed to bind to %s:%d - %s\n", 
+			 bind_address, lpcfg_nbt_port(lp_ctx), nt_errstr(status)));
+		talloc_free(iface);
+		return status;
+	}
+	talloc_free(unicast_address);
+
+	nbt_set_incoming_handler(iface->nbtsock, nbtd_request_handler, iface);
+	nbt_set_unexpected_handler(iface->nbtsock, nbtd_unexpected_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, struct loadparm_context *lp_ctx,
+				 struct interface *ifaces)
+{
+	int num_interfaces = iface_list_count(ifaces);
+	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 (!lpcfg_bind_interfaces_only(lp_ctx)) {
+		const char *primary_address;
+
+		primary_address = iface_list_first_v4(ifaces);
+
+		/* the primary address is the address we will return
+		   for non-WINS queries not made on a specific
+		   interface */
+		if (primary_address == NULL) {
+			primary_address = inet_ntoa(interpret_addr2(
+							    lpcfg_netbios_name(lp_ctx)));
+		}
+
+		primary_address = talloc_strdup(tmp_ctx, primary_address);
+		NT_STATUS_HAVE_NO_MEMORY(primary_address);
+
+		status = nbtd_add_socket(nbtsrv, 
+					 lp_ctx,
+					 "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; i<num_interfaces; i++) {
+		const char *bcast;
+		const char *address, *netmask;
+
+		if (!iface_list_n_is_v4(ifaces, i)) {
+			/* v4 only for NBT protocol */
+			continue;
+		}
+
+		bcast = iface_list_n_bcast(ifaces, i);
+		/* we can't assume every interface is broadcast capable */
+		if (bcast == NULL) continue;
+
+		address = talloc_strdup(tmp_ctx, iface_list_n_ip(ifaces, i));
+		bcast   = talloc_strdup(tmp_ctx, bcast);
+		netmask = talloc_strdup(tmp_ctx, iface_list_n_netmask(ifaces, i));
+
+		status = nbtd_add_socket(nbtsrv, lp_ctx,
+					 address, address, bcast, netmask);
+		NT_STATUS_NOT_OK_RETURN(status);
+	}
+
+	if (lpcfg_wins_server_list(lp_ctx)) {
+		status = nbtd_add_wins_socket(nbtsrv);
+		NT_STATUS_NOT_OK_RETURN(status);
+	}
+
+	talloc_free(tmp_ctx);
+
+	return NT_STATUS_OK;
+}
+
+
+/*
+  form a list of addresses that we should use in name query replies
+  we always place the IP in the given interface first
+*/
+const char **nbtd_address_list(struct nbtd_interface *iface, TALLOC_CTX *mem_ctx)
+{
+	struct nbtd_server *nbtsrv = iface->nbtsrv;
+	const char **ret = NULL;
+	struct nbtd_interface *iface2;
+	bool is_loopback = false;
+
+	if (iface->ip_address) {
+		is_loopback = iface_list_same_net(iface->ip_address, "127.0.0.1", "255.0.0.0");
+		ret = str_list_add(ret, iface->ip_address);
+	}
+
+	for (iface2=nbtsrv->interfaces;iface2;iface2=iface2->next) {
+		if (iface2 == iface) continue;
+
+		if (!iface2->ip_address) continue;
+
+		if (!is_loopback) {
+			if (iface_list_same_net(iface2->ip_address, "127.0.0.1", "255.0.0.0")) {
+				continue;
+			}
+		}
+
+		ret = str_list_add(ret, iface2->ip_address);
+	}
+
+	talloc_steal(mem_ctx, ret);
+
+	return ret;
+}
+
+
+/*
+  find the interface to use for sending a outgoing request
+*/
+struct nbtd_interface *nbtd_find_request_iface(struct nbtd_server *nbtd_server,
+					       const char *address, bool allow_bcast_iface)
+{
+	struct nbtd_interface *cur;
+
+	/* try to find a exact match */
+	for (cur=nbtd_server->interfaces;cur;cur=cur->next) {
+		if (iface_list_same_net(address, cur->ip_address, cur->netmask)) {
+			DEBUG(10,("find interface for dst[%s] ip: %s/%s (iface[%p])\n",
+				  address, cur->ip_address, cur->netmask, cur));
+			return cur;
+		}
+	}
+
+	/* no exact match, if we have the broadcast interface, use that */
+	if (allow_bcast_iface && nbtd_server->bcast_interface) {
+		cur = nbtd_server->bcast_interface;
+		DEBUG(10,("find interface for dst[%s] ip: %s/%s (bcast iface[%p])\n",
+			address, cur->ip_address, cur->netmask, cur));
+		return cur;
+	}
+
+	/* fallback to first interface */
+	cur = nbtd_server->interfaces;
+	DEBUG(10,("find interface for dst[%s] ip: %s/%s (default iface[%p])\n",
+		address, cur->ip_address, cur->netmask, cur));
+	return cur;
+}
+
+/*
+ * find the interface to use for sending a outgoing reply
+ */
+struct nbtd_interface *nbtd_find_reply_iface(struct nbtd_interface *iface,
+					     const char *address, bool allow_bcast_iface)
+{
+	struct nbtd_server *nbtd_server = iface->nbtsrv;
+
+	/* first try to use the given interfacel when it's not the broadcast one */
+	if (iface != nbtd_server->bcast_interface) {
+		return iface;
+	}
+
+	return nbtd_find_request_iface(nbtd_server, address, allow_bcast_iface);
+}