2 Unix SMB/Netbios implementation.
4 NBT netbios routines and daemon - version 2
5 Copyright (C) Andrew Tridgell 1994-1996
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 Module name: nameelect.c
25 14 jan 96: lkcl@pires.co.uk
26 added multiple workgroup domain master support
28 04 jul 96: lkcl@pires.co.uk
29 added system to become a master browser by stages.
37 extern int ClientDGRAM
;
39 extern int DEBUGLEVEL
;
42 extern pstring myname
;
43 extern struct in_addr ipzero
;
44 extern struct in_addr ipgrp
;
46 /* here are my election parameters */
48 extern time_t StartupTime
;
50 extern struct subnet_record
*subnetlist
;
52 extern uint16 nb_type
; /* samba's NetBIOS name type */
54 /*******************************************************************
55 occasionally check to see if the master browser is around
56 ******************************************************************/
57 void check_master_browser(void)
59 static time_t lastrun
=0;
60 time_t t
= time(NULL
);
61 struct subnet_record
*d
;
63 if (!lastrun
) lastrun
= t
;
64 if (t
< lastrun
+ CHECK_TIME_MST_BROWSE
* 60)
70 for (d
= subnetlist
; d
; d
= d
->next
)
72 struct work_record
*work
;
74 for (work
= d
->workgrouplist
; work
; work
= work
->next
)
76 /* if we are not the browse master of a workgroup, and we can't
77 find a browser on the subnet, do something about it. */
81 queue_netbios_packet(d
,ClientNMB
,NMB_QUERY
,NAME_QUERY_MST_CHK
,
82 work
->work_group
,0x1d,0,0,0,NULL
,NULL
,
83 True
,False
,d
->bcast_ip
,d
->bcast_ip
);
90 /*******************************************************************
91 what to do if a master browser DOESN't exist
92 ******************************************************************/
93 void browser_gone(char *work_name
, struct in_addr ip
)
95 struct subnet_record
*d
= find_subnet(ip
);
96 struct work_record
*work
= find_workgroupstruct(d
, work_name
, False
);
98 /* i don't know about this workgroup, therefore i don't care */
99 if (!work
|| !d
) return;
101 /* don't do election stuff on the WINS subnet */
102 if (ip_equal(d
->bcast_ip
,ipgrp
))
105 if (strequal(work
->work_group
, lp_workgroup()))
108 DEBUG(2,("Forcing election on %s %s\n",
109 work
->work_group
,inet_ntoa(d
->bcast_ip
)));
111 /* we can attempt to become master browser */
112 work
->needelection
= True
;
116 /* local interfaces: force an election */
117 send_election(d
, work
->work_group
, 0, 0, myname
);
119 /* only removes workgroup completely on a local interface
120 persistent lmhosts entries on a local interface _will_ be removed).
122 remove_workgroup(d
, work
,True
);
127 /****************************************************************************
128 send an election packet
129 **************************************************************************/
130 void send_election(struct subnet_record
*d
, char *group
,uint32 criterion
,
131 int timeup
,char *name
)
138 DEBUG(2,("Sending election to %s for workgroup %s\n",
139 inet_ntoa(d
->bcast_ip
),group
));
141 bzero(outbuf
,sizeof(outbuf
));
143 CVAL(p
,0) = ANN_Election
; /* election */
146 CVAL(p
,0) = (criterion
== 0 && timeup
== 0) ? 0 : ELECTION_VERSION
;
147 SIVAL(p
,1,criterion
);
148 SIVAL(p
,5,timeup
*1000); /* ms - despite the spec */
152 p
= skip_string(p
,1);
154 send_mailslot_reply(BROWSE_MAILSLOT
,ClientDGRAM
,outbuf
,PTR_DIFF(p
,outbuf
),
155 name
,group
,0,0x1e,d
->bcast_ip
,*iface_ip(d
->bcast_ip
));
159 /****************************************************************************
160 un-register a SELF name that got rejected.
162 if this name happens to be rejected when samba is in the process
163 of becoming a master browser (registering __MSBROWSE__, WORKGROUP(1d)
164 or WORKGROUP(1b)) then we must stop being a master browser. sad.
166 **************************************************************************/
167 void name_unregister_work(struct subnet_record
*d
, char *name
, int name_type
)
169 struct work_record
*work
;
171 remove_netbios_name(d
,name
,name_type
,SELF
,ipzero
);
173 if (!(work
= find_workgroupstruct(d
, name
, False
))) return;
175 if (ms_browser_name(name
, name_type
) ||
176 (AM_MASTER(work
) && strequal(name
, lp_workgroup()) == 0 &&
177 (name_type
== 0x1d || name_type
== 0x1b)))
181 if (ms_browser_name(name
, name_type
))
182 remove_type
= SV_TYPE_MASTER_BROWSER
|SV_TYPE_DOMAIN_MASTER
;
183 if (name_type
== 0x1d)
184 remove_type
= SV_TYPE_MASTER_BROWSER
;
185 if (name_type
== 0x1b)
186 remove_type
= SV_TYPE_DOMAIN_MASTER
;
188 become_nonmaster(d
, work
, remove_type
);
193 /****************************************************************************
196 if the name being added is a SELF name, we must additionally check
197 whether to proceed to the next stage in samba becoming a master browser.
199 **************************************************************************/
200 void name_register_work(struct subnet_record
*d
, char *name
, int name_type
,
201 int nb_flags
, time_t ttl
, struct in_addr ip
, BOOL bcast
)
203 enum name_source source
= (ismyip(ip
) || ip_equal(ip
, ipzero
)) ?
208 struct work_record
*work
= find_workgroupstruct(d
, lp_workgroup(), False
);
210 add_netbios_entry(d
,name
,name_type
,nb_flags
,ttl
,source
,ip
,True
,!bcast
);
214 if (work
->state
!= MST_NONE
)
216 /* samba is in the process of working towards master browser-ness.
217 initiate the next stage.
219 become_master(d
, work
);
227 /*******************************************************************
228 become the master browser.
230 this is done in stages. note that this could take a while,
231 particularly on a broadcast subnet, as we have to wait for
232 the implicit registration of each name to be accepted.
234 as each name is successfully registered, become_master() is
235 called again, in order to initiate the next stage. see
236 dead_netbios_entry() - deals with implicit name registration
237 and response_name_reg() - deals with explicit registration
240 stage 1: was MST_NONE - go to MST_NONE and register ^1^2__MSBROWSE__^2^1.
241 stage 2: was MST_WON - go to MST_MSB and register WORKGROUP(0x1d)
242 stage 3: was MST_MSB - go to MST_BROWSER and register WORKGROUP(0x1b)
243 stage 4: was MST_BROWSER - go to MST_DOMAIN (do not pass GO, do not...)
245 XXXX note: this code still does not cope with the distinction
246 between different types of nodes, particularly between M and P
247 nodes. that comes later.
249 ******************************************************************/
250 void become_master(struct subnet_record
*d
, struct work_record
*work
)
252 uint32 domain_type
= SV_TYPE_DOMAIN_ENUM
|DFLT_SERVER_TYPE
|
253 SV_TYPE_POTENTIAL_BROWSER
;
257 DEBUG(2,("Becoming master for %s %s (currently at stage %d)\n",
258 work
->work_group
,inet_ntoa(d
->bcast_ip
),work
->state
));
262 case MST_NONE
: /* while we were nothing but a server... */
264 DEBUG(3,("go to first stage: register ^1^2__MSBROWSE__^2^1\n"));
265 work
->state
= MST_WON
; /* ... an election win was successful */
267 work
->ElectionCriterion
|= 0x5;
269 /* update our server status */
270 work
->ServerType
&= ~SV_TYPE_POTENTIAL_BROWSER
;
271 add_server_entry(d
,work
,myname
,work
->ServerType
,0,lp_serverstring(),True
);
273 /* add special browser name */
274 add_my_name_entry(d
,MSBROWSE
,0x01,nb_type
|NB_ACTIVE
|NB_GROUP
);
276 /* DON'T do anything else after calling add_my_name_entry() */
279 case MST_WON
: /* while nothing had happened except we won an election... */
281 DEBUG(3,("go to second stage: register as master browser\n"));
282 work
->state
= MST_MSB
; /* ... registering MSBROWSE was successful */
284 /* add server entry on successful registration of MSBROWSE */
285 add_server_entry(d
,work
,work
->work_group
,domain_type
,0,myname
,True
);
287 /* add master name */
288 add_my_name_entry(d
,work
->work_group
,0x1d,nb_type
|NB_ACTIVE
);
290 /* DON'T do anything else after calling add_my_name_entry() */
293 case MST_MSB
: /* while we were still only registered MSBROWSE state... */
295 DEBUG(3,("2nd stage complete: registered as master browser\n"));
296 work
->state
= MST_BROWSER
; /* ... registering WORKGROUP(1d) succeeded */
298 /* update our server status */
299 work
->ServerType
|= SV_TYPE_MASTER_BROWSER
;
300 add_server_entry(d
,work
,myname
,work
->ServerType
,0,lp_serverstring(),True
);
302 if (work
->serverlist
== NULL
) /* no servers! */
304 /* ask all servers on our local net to announce to us */
305 announce_request(work
, d
->bcast_ip
);
312 /* don't have to do anything: just report success */
313 DEBUG(3,("3rd stage: become master browser!\n"));
318 case MST_DOMAIN_NONE
:
320 if (lp_domain_master())
322 work
->state
= MST_DOMAIN_MEM
; /* ... become domain member */
323 DEBUG(3,("domain first stage: register as domain member\n"));
325 /* add domain member name */
326 add_my_name_entry(d
,work
->work_group
,0x1e,nb_type
|NB_ACTIVE
|NB_GROUP
);
328 /* DON'T do anything else after calling add_my_name_entry() */
333 DEBUG(4,("samba not configured as a domain master.\n"));
341 if (lp_domain_master())
343 work
->state
= MST_DOMAIN_TST
; /* ... possibly become domain master */
344 DEBUG(3,("domain second stage: register as domain master\n"));
346 if (lp_domain_logons())
348 work
->ServerType
|= SV_TYPE_DOMAIN_MEMBER
;
349 add_server_entry(d
,work
,myname
,work
->ServerType
,0,lp_serverstring(),True
);
352 /* add domain master name */
353 add_my_name_entry(d
,work
->work_group
,0x1b,nb_type
|NB_ACTIVE
);
355 /* DON'T do anything else after calling add_my_name_entry() */
360 DEBUG(4,("samba not configured as a domain master.\n"));
366 case MST_DOMAIN_TST
: /* while we were still a master browser... */
368 /* update our server status */
369 if (lp_domain_master())
371 struct subnet_record
*d1
;
372 uint32 update_type
= 0;
374 DEBUG(3,("domain third stage: samba is now a domain master.\n"));
375 work
->state
= MST_DOMAIN
; /* ... registering WORKGROUP(1b) succeeded */
377 update_type
|= DFLT_SERVER_TYPE
| SV_TYPE_DOMAIN_MASTER
|
378 SV_TYPE_POTENTIAL_BROWSER
;
380 work
->ServerType
|= update_type
;
381 add_server_entry(d
,work
,myname
,work
->ServerType
,0,lp_serverstring(),True
);
383 for (d1
= subnetlist
; d1
; d1
= d1
->next
)
385 struct work_record
*w
;
386 if (ip_equal(d1
->bcast_ip
, d
->bcast_ip
)) continue;
388 for (w
= d1
->workgrouplist
; w
; w
= w
->next
)
390 struct server_record
*s
= find_server(w
, myname
);
391 if (strequal(w
->work_group
, work
->work_group
))
393 w
->ServerType
|= update_type
;
397 s
->serv
.type
|= update_type
;
398 DEBUG(4,("found server %s on %s: update to %8x\n",
399 s
->serv
.name
, inet_ntoa(d1
->bcast_ip
),
411 /* don't have to do anything: just report success */
412 DEBUG(3,("fifth stage: there isn't one yet!\n"));
419 /*******************************************************************
420 unbecome the master browser. initates removal of necessary netbios
421 names, and tells the world that we are no longer a master browser.
422 ******************************************************************/
423 void become_nonmaster(struct subnet_record
*d
, struct work_record
*work
,
426 int new_server_type
= work
->ServerType
;
428 DEBUG(2,("Becoming non-master for %s\n",work
->work_group
));
430 /* can only remove master or domain types with this function */
431 remove_type
&= SV_TYPE_MASTER_BROWSER
|SV_TYPE_DOMAIN_MASTER
;
433 /* unbecome a master browser; unbecome a domain master, too :-( */
434 if (remove_type
& SV_TYPE_MASTER_BROWSER
)
435 remove_type
|= SV_TYPE_DOMAIN_MASTER
;
437 new_server_type
&= ~remove_type
;
439 if (!(new_server_type
& (SV_TYPE_MASTER_BROWSER
|SV_TYPE_DOMAIN_MASTER
)))
441 /* no longer a master browser of any sort */
443 work
->ServerType
|= SV_TYPE_POTENTIAL_BROWSER
;
444 work
->ElectionCriterion
&= ~0x4;
445 work
->state
= MST_NONE
;
447 /* announce ourselves as no longer active as a master browser. */
448 announce_server(d
, work
, work
->work_group
, myname
, 0, 0);
449 remove_name_entry(d
,MSBROWSE
,0x01);
452 work
->ServerType
= new_server_type
;
454 if (!(work
->ServerType
& SV_TYPE_DOMAIN_MASTER
))
456 if (work
->state
== MST_DOMAIN
)
457 work
->state
= MST_BROWSER
;
458 remove_name_entry(d
,work
->work_group
,0x1b);
461 if (!(work
->ServerType
& SV_TYPE_MASTER_BROWSER
))
463 if (work
->state
>= MST_BROWSER
)
464 work
->state
= MST_NONE
;
465 remove_name_entry(d
,work
->work_group
,0x1d);
470 /*******************************************************************
472 ******************************************************************/
473 void run_elections(void)
475 time_t t
= time(NULL
);
476 static time_t lastime
= 0;
478 struct subnet_record
*d
;
480 /* send election packets once a second */
481 if (lastime
&& t
-lastime
<= 0) return;
485 for (d
= subnetlist
; d
; d
= d
->next
)
487 struct work_record
*work
;
488 for (work
= d
->workgrouplist
; work
; work
= work
->next
)
490 if (work
->RunningElection
)
492 send_election(d
,work
->work_group
, work
->ElectionCriterion
,
493 t
-StartupTime
,myname
);
495 if (work
->ElectionCount
++ >= 4)
497 /* I won! now what :-) */
498 DEBUG(2,(">>> Won election on %s %s <<<\n",
499 work
->work_group
,inet_ntoa(d
->bcast_ip
)));
501 work
->RunningElection
= False
;
502 work
->state
= MST_NONE
;
504 become_master(d
, work
);
512 /*******************************************************************
513 work out if I win an election
514 ******************************************************************/
515 static BOOL
win_election(struct work_record
*work
,int version
,uint32 criterion
,
516 int timeup
,char *name
)
518 int mytimeup
= time(NULL
) - StartupTime
;
519 uint32 mycriterion
= work
->ElectionCriterion
;
521 DEBUG(4,("election comparison: %x:%x %x:%x %d:%d %s:%s\n",
522 version
,ELECTION_VERSION
,
523 criterion
,mycriterion
,
527 if (version
> ELECTION_VERSION
) return(False
);
528 if (version
< ELECTION_VERSION
) return(True
);
530 if (criterion
> mycriterion
) return(False
);
531 if (criterion
< mycriterion
) return(True
);
533 if (timeup
> mytimeup
) return(False
);
534 if (timeup
< mytimeup
) return(True
);
536 if (strcasecmp(myname
,name
) > 0) return(False
);
542 /*******************************************************************
543 process a election packet
545 An election dynamically decides who will be the master.
546 ******************************************************************/
547 void process_election(struct packet_struct
*p
,char *buf
)
549 struct dgram_packet
*dgram
= &p
->packet
.dgram
;
550 struct in_addr ip
= dgram
->header
.source_ip
;
551 struct subnet_record
*d
= find_subnet(ip
);
552 int version
= CVAL(buf
,0);
553 uint32 criterion
= IVAL(buf
,1);
554 int timeup
= IVAL(buf
,5)/1000;
556 struct work_record
*work
;
560 if (ip_equal(d
->bcast_ip
,ipgrp
)) {
561 DEBUG(3,("Unexpected election request from %s %s on WINS net\n",
562 name
, inet_ntoa(p
->ip
)));
568 DEBUG(3,("Election request from %s %s vers=%d criterion=%08x timeup=%d\n",
569 name
,inet_ntoa(p
->ip
),version
,criterion
,timeup
));
571 if (same_context(dgram
)) return;
573 for (work
= d
->workgrouplist
; work
; work
= work
->next
)
575 if (!strequal(work
->work_group
, lp_workgroup()))
578 if (win_election(work
, version
,criterion
,timeup
,name
)) {
579 if (!work
->RunningElection
) {
580 work
->needelection
= True
;
581 work
->ElectionCount
=0;
582 work
->state
= MST_NONE
;
585 work
->needelection
= False
;
587 if (work
->RunningElection
|| AM_MASTER(work
)) {
588 work
->RunningElection
= False
;
589 DEBUG(3,(">>> Lost election on %s %s <<<\n",
590 work
->work_group
,inet_ntoa(d
->bcast_ip
)));
592 become_nonmaster(d
, work
,
593 SV_TYPE_MASTER_BROWSER
|
594 SV_TYPE_DOMAIN_MASTER
);
601 /****************************************************************************
602 checks whether a browser election is to be run on any workgroup
604 this function really ought to return the time between election
605 packets (which depends on whether samba intends to be a domain
606 master or a master browser) in milliseconds.
608 ***************************************************************************/
609 BOOL
check_elections(void)
611 struct subnet_record
*d
;
612 BOOL run_any_election
= False
;
614 for (d
= subnetlist
; d
; d
= d
->next
)
616 struct work_record
*work
;
617 for (work
= d
->workgrouplist
; work
; work
= work
->next
)
619 run_any_election
|= work
->RunningElection
;
621 if (work
->needelection
&& !work
->RunningElection
)
623 DEBUG(3,(">>> Starting election on %s %s <<<\n",
624 work
->work_group
,inet_ntoa(d
->bcast_ip
)));
625 work
->ElectionCount
= 0;
626 work
->RunningElection
= True
;
627 work
->needelection
= False
;
631 return run_any_election
;