source: trunk/server/source3/nmbd/nmbd_subnetdb.c

Last change on this file was 745, checked in by Silvan Scherrer, 13 years ago

Samba Server: updated trunk to 3.6.0
File size: 12.3 KB
Line 
1/*
2 Unix SMB/CIFS implementation.
3 NBT netbios routines and daemon - version 2
4 Copyright (C) Andrew Tridgell 1994-1998
5 Copyright (C) Luke Kenneth Casson Leighton 1994-1998
6 Copyright (C) Jeremy Allison 1994-1998
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>.
20
21 Revision History:
22
23*/
24
25#include "includes.h"
26#include "nmbd/nmbd.h"
27
28extern int global_nmb_port;
29
30/* This is the broadcast subnets database. */
31struct subnet_record *subnetlist = NULL;
32
33/* Extra subnets - keep these separate so enumeration code doesn't
34 run onto it by mistake. */
35
36struct subnet_record *unicast_subnet = NULL;
37struct subnet_record *remote_broadcast_subnet = NULL;
38struct subnet_record *wins_server_subnet = NULL;
39
40extern uint16 samba_nb_type; /* Samba's NetBIOS name type. */
41
42/****************************************************************************
43 Add a subnet into the list.
44 **************************************************************************/
45
46static void add_subnet(struct subnet_record *subrec)
47{
48 DLIST_ADD(subnetlist, subrec);
49}
50
51/****************************************************************************
52stop listening on a subnet
53we don't free the record as we don't have proper reference counting for it
54yet and it may be in use by a response record
55 ****************************************************************************/
56
57void close_subnet(struct subnet_record *subrec)
58{
59 if (subrec->nmb_sock != -1) {
60 close(subrec->nmb_sock);
61 subrec->nmb_sock = -1;
62 }
63 if (subrec->nmb_bcast != -1) {
64 close(subrec->nmb_bcast);
65 subrec->nmb_bcast = -1;
66 }
67 if (subrec->dgram_sock != -1) {
68 close(subrec->dgram_sock);
69 subrec->dgram_sock = -1;
70 }
71 if (subrec->dgram_bcast != -1) {
72 close(subrec->dgram_bcast);
73 subrec->dgram_bcast = -1;
74 }
75
76 DLIST_REMOVE(subnetlist, subrec);
77}
78
79/****************************************************************************
80 Create a subnet entry.
81 ****************************************************************************/
82
83static struct subnet_record *make_subnet(const char *name, enum subnet_type type,
84 struct in_addr myip, struct in_addr bcast_ip,
85 struct in_addr mask_ip)
86{
87 struct subnet_record *subrec = NULL;
88 int nmb_sock = -1;
89 int dgram_sock = -1;
90 int nmb_bcast = -1;
91 int dgram_bcast = -1;
92 bool bind_bcast = lp_nmbd_bind_explicit_broadcast();
93
94 /* Check if we are creating a non broadcast subnet - if so don't create
95 sockets. */
96
97 if (type == NORMAL_SUBNET) {
98 struct sockaddr_storage ss;
99 struct sockaddr_storage ss_bcast;
100
101 in_addr_to_sockaddr_storage(&ss, myip);
102 in_addr_to_sockaddr_storage(&ss_bcast, bcast_ip);
103
104 /*
105 * Attempt to open the sockets on port 137/138 for this interface
106 * and bind them.
107 * Fail the subnet creation if this fails.
108 */
109
110 nmb_sock = open_socket_in(SOCK_DGRAM, global_nmb_port,
111 0, &ss, true);
112 if (nmb_sock == -1) {
113 DEBUG(0, ("nmbd_subnetdb:make_subnet()\n"));
114 DEBUGADD(0,(" Failed to open nmb socket on interface %s ",
115 inet_ntoa(myip)));
116 DEBUGADD(0,("for port %d. ", global_nmb_port));
117 DEBUGADD(0,("Error was %s\n", strerror(errno)));
118 goto failed;
119 }
120 set_socket_options(nmb_sock,"SO_BROADCAST");
121 set_blocking(nmb_sock, false);
122
123 if (bind_bcast) {
124 nmb_bcast = open_socket_in(SOCK_DGRAM, global_nmb_port,
125 0, &ss_bcast, true);
126 if (nmb_bcast == -1) {
127 DEBUG(0, ("nmbd_subnetdb:make_subnet()\n"));
128 DEBUGADD(0,(" Failed to open nmb bcast socket on interface %s ",
129 inet_ntoa(bcast_ip)));
130 DEBUGADD(0,("for port %d. ", global_nmb_port));
131 DEBUGADD(0,("Error was %s\n", strerror(errno)));
132 goto failed;
133 }
134 set_socket_options(nmb_bcast, "SO_BROADCAST");
135 set_blocking(nmb_bcast, false);
136 }
137
138 dgram_sock = open_socket_in(SOCK_DGRAM, DGRAM_PORT,
139 3, &ss, true);
140 if (dgram_sock == -1) {
141 DEBUG(0, ("nmbd_subnetdb:make_subnet()\n"));
142 DEBUGADD(0,(" Failed to open dgram socket on interface %s ",
143 inet_ntoa(myip)));
144 DEBUGADD(0,("for port %d. ", DGRAM_PORT));
145 DEBUGADD(0,("Error was %s\n", strerror(errno)));
146 goto failed;
147 }
148 set_socket_options(dgram_sock, "SO_BROADCAST");
149 set_blocking(dgram_sock, false);
150
151 if (bind_bcast) {
152 dgram_bcast = open_socket_in(SOCK_DGRAM, DGRAM_PORT,
153 3, &ss_bcast, true);
154 if (dgram_bcast == -1) {
155 DEBUG(0, ("nmbd_subnetdb:make_subnet()\n"));
156 DEBUGADD(0,(" Failed to open dgram bcast socket on interface %s ",
157 inet_ntoa(bcast_ip)));
158 DEBUGADD(0,("for port %d. ", DGRAM_PORT));
159 DEBUGADD(0,("Error was %s\n", strerror(errno)));
160 goto failed;
161 }
162 set_socket_options(dgram_bcast, "SO_BROADCAST");
163 set_blocking(dgram_bcast, false);
164 }
165 }
166
167 subrec = SMB_MALLOC_P(struct subnet_record);
168 if (!subrec) {
169 DEBUG(0,("make_subnet: malloc fail !\n"));
170 goto failed;
171 }
172
173 ZERO_STRUCTP(subrec);
174
175 if((subrec->subnet_name = SMB_STRDUP(name)) == NULL) {
176 DEBUG(0,("make_subnet: malloc fail for subnet name !\n"));
177 goto failed;
178 }
179
180 DEBUG(2, ("making subnet name:%s ", name ));
181 DEBUG(2, ("Broadcast address:%s ", inet_ntoa(bcast_ip)));
182 DEBUG(2, ("Subnet mask:%s\n", inet_ntoa(mask_ip)));
183
184 subrec->namelist_changed = False;
185 subrec->work_changed = False;
186
187 subrec->bcast_ip = bcast_ip;
188 subrec->mask_ip = mask_ip;
189 subrec->myip = myip;
190 subrec->type = type;
191 subrec->nmb_sock = nmb_sock;
192 subrec->nmb_bcast = nmb_bcast;
193 subrec->dgram_sock = dgram_sock;
194 subrec->dgram_bcast = dgram_bcast;
195
196 return subrec;
197
198failed:
199 SAFE_FREE(subrec);
200 if (nmb_sock != -1) {
201 close(nmb_sock);
202 }
203 if (nmb_bcast != -1) {
204 close(nmb_bcast);
205 }
206 if (dgram_sock != -1) {
207 close(dgram_sock);
208 }
209 if (dgram_bcast != -1) {
210 close(dgram_bcast);
211 }
212 return NULL;
213}
214
215/****************************************************************************
216 Create a normal subnet
217**************************************************************************/
218
219struct subnet_record *make_normal_subnet(const struct interface *iface)
220{
221
222 struct subnet_record *subrec;
223 const struct in_addr *pip = &((const struct sockaddr_in *)&iface->ip)->sin_addr;
224 const struct in_addr *pbcast = &((const struct sockaddr_in *)&iface->bcast)->sin_addr;
225 const struct in_addr *pnmask = &((const struct sockaddr_in *)&iface->netmask)->sin_addr;
226
227 subrec = make_subnet(inet_ntoa(*pip), NORMAL_SUBNET,
228 *pip, *pbcast, *pnmask);
229 if (subrec) {
230 add_subnet(subrec);
231 }
232 return subrec;
233}
234
235/****************************************************************************
236 Create subnet entries.
237**************************************************************************/
238
239bool create_subnets(void)
240{
241 /* We only count IPv4 interfaces whilst we're waiting. */
242 int num_interfaces;
243 int i;
244 struct in_addr unicast_ip, ipzero;
245
246 try_interfaces_again:
247
248 /* Only count IPv4, non-loopback interfaces. */
249 if (iface_count_v4_nl() == 0) {
250 DEBUG(0,("create_subnets: No local IPv4 non-loopback interfaces !\n"));
251 DEBUG(0,("create_subnets: Waiting for an interface to appear ...\n"));
252 }
253
254 /* We only count IPv4, non-loopback interfaces here. */
255 while (iface_count_v4_nl() == 0) {
256 void (*saved_handler)(int);
257
258 /*
259 * Whilst we're waiting for an interface, allow SIGTERM to
260 * cause us to exit.
261 */
262
263 saved_handler = CatchSignal(SIGTERM, SIG_DFL);
264
265 sleep(5);
266 load_interfaces();
267
268 /*
269 * We got an interface, restore our normal term handler.
270 */
271
272 CatchSignal(SIGTERM, saved_handler);
273 }
274
275 /*
276 * Here we count v4 and v6 - we know there's at least one
277 * IPv4 interface and we filter on it below.
278 */
279 num_interfaces = iface_count();
280
281 /*
282 * Create subnets from all the local interfaces and thread them onto
283 * the linked list.
284 */
285
286 for (i = 0 ; i < num_interfaces; i++) {
287 const struct interface *iface = get_interface(i);
288
289 if (!iface) {
290 DEBUG(2,("create_subnets: can't get interface %d.\n", i ));
291 continue;
292 }
293
294 /* Ensure we're only dealing with IPv4 here. */
295 if (iface->ip.ss_family != AF_INET) {
296 DEBUG(2,("create_subnets: "
297 "ignoring non IPv4 interface.\n"));
298 continue;
299 }
300
301 /*
302 * We don't want to add a loopback interface, in case
303 * someone has added 127.0.0.1 for smbd, nmbd needs to
304 * ignore it here. JRA.
305 */
306
307 if (is_loopback_addr((struct sockaddr *)&iface->ip)) {
308 DEBUG(2,("create_subnets: Ignoring loopback interface.\n" ));
309 continue;
310 }
311
312 if (!make_normal_subnet(iface))
313 return False;
314 }
315
316 /* We must have at least one subnet. */
317 if (subnetlist == NULL) {
318 void (*saved_handler)(int);
319
320 DEBUG(0,("create_subnets: Unable to create any subnet from "
321 "given interfaces. Is your interface line in "
322 "smb.conf correct ?\n"));
323
324 saved_handler = CatchSignal(SIGTERM, SIG_DFL);
325
326 sleep(5);
327 load_interfaces();
328
329 CatchSignal(SIGTERM, saved_handler);
330 goto try_interfaces_again;
331 }
332
333 if (lp_we_are_a_wins_server()) {
334 /* Pick the first interface IPv4 address as the WINS server
335 * ip. */
336 const struct in_addr *nip = first_ipv4_iface();
337
338 if (!nip) {
339 return False;
340 }
341
342 unicast_ip = *nip;
343 } else {
344 /* note that we do not set the wins server IP here. We just
345 set it at zero and let the wins registration code cope
346 with getting the IPs right for each packet */
347 zero_ip_v4(&unicast_ip);
348 }
349
350 /*
351 * Create the unicast and remote broadcast subnets.
352 * Don't put these onto the linked list.
353 * The ip address of the unicast subnet is set to be
354 * the WINS server address, if it exists, or ipzero if not.
355 */
356
357 unicast_subnet = make_subnet( "UNICAST_SUBNET", UNICAST_SUBNET,
358 unicast_ip, unicast_ip, unicast_ip);
359
360 zero_ip_v4(&ipzero);
361
362 remote_broadcast_subnet = make_subnet( "REMOTE_BROADCAST_SUBNET",
363 REMOTE_BROADCAST_SUBNET,
364 ipzero, ipzero, ipzero);
365
366 if((unicast_subnet == NULL) || (remote_broadcast_subnet == NULL))
367 return False;
368
369 /*
370 * If we are WINS server, create the WINS_SERVER_SUBNET - don't put on
371 * the linked list.
372 */
373
374 if (lp_we_are_a_wins_server()) {
375 if( (wins_server_subnet = make_subnet( "WINS_SERVER_SUBNET",
376 WINS_SERVER_SUBNET,
377 ipzero, ipzero, ipzero )) == NULL )
378 return False;
379 }
380
381 return True;
382}
383
384/*******************************************************************
385Function to tell us if we can use the unicast subnet.
386******************************************************************/
387
388bool we_are_a_wins_client(void)
389{
390 if (wins_srv_count() > 0) {
391 return True;
392 }
393
394 return False;
395}
396
397/*******************************************************************
398Access function used by NEXT_SUBNET_INCLUDING_UNICAST
399******************************************************************/
400
401struct subnet_record *get_next_subnet_maybe_unicast(struct subnet_record *subrec)
402{
403 if(subrec == unicast_subnet)
404 return NULL;
405 else if((subrec->next == NULL) && we_are_a_wins_client())
406 return unicast_subnet;
407 else
408 return subrec->next;
409}
410
411/*******************************************************************
412 Access function used by retransmit_or_expire_response_records() in
413 nmbd_packets.c. Patch from Andrey Alekseyev <fetch@muffin.arcadia.spb.ru>
414 Needed when we need to enumerate all the broadcast, unicast and
415 WINS subnets.
416******************************************************************/
417
418struct subnet_record *get_next_subnet_maybe_unicast_or_wins_server(struct subnet_record *subrec)
419{
420 if(subrec == unicast_subnet) {
421 if(wins_server_subnet)
422 return wins_server_subnet;
423 else
424 return NULL;
425 }
426
427 if(wins_server_subnet && subrec == wins_server_subnet)
428 return NULL;
429
430 if((subrec->next == NULL) && we_are_a_wins_client())
431 return unicast_subnet;
432 else
433 return subrec->next;
434}
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