2 Unix SMB/Netbios implementation.
4 NBT netbios routines and daemon - version 2
5 Copyright (C) Andrew Tridgell 1994-1995
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.
23 14 jan 96: lkcl@pires.co.uk
24 added multiple workgroup domain master support
32 extern int ClientDGRAM;
34 extern int DEBUGLEVEL;
37 extern pstring myname;
39 /* machine comment for host announcements */
40 extern pstring ServerComment;
42 /* here are my election parameters */
44 extern time_t StartupTime;
46 #define AM_MASTER(work) (work->ServerType & SV_TYPE_MASTER_BROWSER)
48 #define MSBROWSE "\001\002__MSBROWSE__\002"
49 #define BROWSE_MAILSLOT "\\MAILSLOT\\BROWSE"
51 extern struct domain_record *domainlist;
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 domain_record *d;
63 if (!lastrun) lastrun = t;
64 if (t < lastrun + 5*60) return;
69 for (d = domainlist; d; d = d->next)
71 struct work_record *work;
73 for (work = d->workgrouplist; work; work = work->next)
75 /* if we are not the browse master of a workgroup, and we can't
76 find a browser on the subnet, do something about it. */
80 queue_netbios_packet(ClientNMB,NMB_QUERY,CHECK_MASTER,
81 work->work_group,0x1d,0,
82 True,False,d->bcast_ip);
89 /*******************************************************************
90 what to do if a master browser DOESN't exist
91 ******************************************************************/
92 void browser_gone(char *work_name, struct in_addr ip)
94 struct domain_record *d = find_domain(ip);
95 struct work_record *work = find_workgroupstruct(d, work_name, False);
97 if (!work || !d) return;
99 if (strequal(work->work_group, lp_workgroup()) &&
100 ismybcast(d->bcast_ip))
103 DEBUG(2,("Forcing election on %s %s\n",
104 work->work_group,inet_ntoa(d->bcast_ip)));
106 /* we can attempt to become master browser */
107 work->needelection = True;
111 DEBUG(2,("no master browser for persistent entry %s %s\n",
112 work->work_group, inet_ntoa(d->bcast_ip)));
114 /* XXXX oh dear. we are going to have problems here. the
115 entry is a persistent one, there isn't anyone responsible
116 for this workgroup up and running, yet we can't find it
117 and we are going to continually have name_queries until
118 a master browser is found for this workgroup on the
124 /****************************************************************************
125 send an election packet
126 **************************************************************************/
127 void send_election(struct domain_record *d, char *group,uint32 criterion,
128 int timeup,char *name)
135 DEBUG(2,("Sending election to %s for workgroup %s\n",
136 inet_ntoa(d->bcast_ip),group));
138 bzero(outbuf,sizeof(outbuf));
140 CVAL(p,0) = 8; /* election */
143 CVAL(p,0) = (criterion == 0 && timeup == 0) ? 0 : ELECTION_VERSION;
144 SIVAL(p,1,criterion);
145 SIVAL(p,5,timeup*1000); /* ms - despite the spec */
149 p = skip_string(p,1);
151 send_mailslot_reply(BROWSE_MAILSLOT,ClientDGRAM,outbuf,PTR_DIFF(p,outbuf),
152 name,group,0,0x1e,d->bcast_ip,*iface_ip(d->bcast_ip));
156 /*******************************************************************
157 become the master browser
158 ******************************************************************/
159 static void become_master(struct domain_record *d, struct work_record *work)
161 uint32 domain_type = SV_TYPE_DOMAIN_ENUM | SV_TYPE_SERVER_UNIX | 0x00400000;
165 DEBUG(2,("Becoming master for %s\n",work->work_group));
167 work->ServerType |= SV_TYPE_MASTER_BROWSER;
168 work->ServerType &= ~SV_TYPE_POTENTIAL_BROWSER;
169 work->ElectionCriterion |= 0x5;
171 /* add browse, master and general names to database or register with WINS */
172 add_name_entry(MSBROWSE ,0x01,NB_ACTIVE|NB_GROUP);
173 add_name_entry(work->work_group,0x1d,NB_ACTIVE );
175 if (lp_domain_master())
177 DEBUG(4,("Domain master: adding names...\n"));
179 /* add domain master and domain member names or register with WINS */
180 add_name_entry(work->work_group,0x1b,NB_ACTIVE );
181 add_name_entry(work->work_group,0x1c,NB_ACTIVE|NB_GROUP);
183 work->ServerType |= SV_TYPE_DOMAIN_MASTER;
185 if (lp_domain_logons())
187 work->ServerType |= SV_TYPE_DOMAIN_CTRL;
188 work->ServerType |= SV_TYPE_DOMAIN_MEMBER;
192 /* update our server status */
193 add_server_entry(d,work,work->work_group,domain_type,0,myname,True);
194 add_server_entry(d,work,myname,work->ServerType,0,ServerComment,True);
196 if (ismybcast(d->bcast_ip))
198 /* ask all servers on our local net to announce to us */
199 announce_request(work, d->bcast_ip);
204 /*******************************************************************
205 unbecome the master browser
206 ******************************************************************/
207 void become_nonmaster(struct domain_record *d, struct work_record *work)
209 DEBUG(2,("Becoming non-master for %s\n",work->work_group));
211 work->ServerType &= ~SV_TYPE_MASTER_BROWSER;
212 work->ServerType &= ~SV_TYPE_DOMAIN_MASTER;
213 work->ServerType |= SV_TYPE_POTENTIAL_BROWSER;
215 work->ElectionCriterion &= ~0x4;
217 remove_name_entry(work->work_group,0x1b);
218 remove_name_entry(work->work_group,0x1c);
219 remove_name_entry(work->work_group,0x1d);
220 remove_name_entry(MSBROWSE ,0x01);
224 /*******************************************************************
226 ******************************************************************/
227 void run_elections(void)
229 time_t t = time(NULL);
230 static time_t lastime = 0;
232 struct domain_record *d;
234 /* send election packets once a second */
235 if (lastime && t-lastime <= 0) return;
239 for (d = domainlist; d; d = d->next)
241 struct work_record *work;
242 for (work = d->workgrouplist; work; work = work->next)
244 if (work->RunningElection)
246 send_election(d,work->work_group, work->ElectionCriterion,
247 t-StartupTime,myname);
249 if (work->ElectionCount++ >= 4)
251 /* I won! now what :-) */
252 DEBUG(2,(">>> Won election on %s %s <<<\n",
253 work->work_group,inet_ntoa(d->bcast_ip)));
255 work->RunningElection = False;
256 become_master(d, work);
264 /*******************************************************************
265 work out if I win an election
266 ******************************************************************/
267 static BOOL win_election(struct work_record *work,int version,uint32 criterion,
268 int timeup,char *name)
270 time_t t = time(NULL);
272 if (version > ELECTION_VERSION) return(False);
273 if (version < ELECTION_VERSION) return(True);
275 mycriterion = work->ElectionCriterion;
277 if (criterion > mycriterion) return(False);
278 if (criterion < mycriterion) return(True);
280 if (timeup > (t - StartupTime)) return(False);
281 if (timeup < (t - StartupTime)) return(True);
283 if (strcasecmp(myname,name) > 0) return(False);
289 /*******************************************************************
290 process a election packet
292 An election dynamically decides who will be the master.
293 ******************************************************************/
294 void process_election(struct packet_struct *p,char *buf)
296 struct dgram_packet *dgram = &p->packet.dgram;
297 struct in_addr ip = dgram->header.source_ip;
298 struct domain_record *d = find_domain(ip);
299 int version = CVAL(buf,0);
300 uint32 criterion = IVAL(buf,1);
301 int timeup = IVAL(buf,5)/1000;
303 struct work_record *work;
309 DEBUG(3,("Election request from %s vers=%d criterion=%08x timeup=%d\n",
310 name,version,criterion,timeup));
312 if (same_context(dgram)) return;
314 for (work = d->workgrouplist; work; work = work->next)
316 if (listening_name(work, &dgram->dest_name) &&
317 strequal(work->work_group, lp_workgroup()) &&
318 ismybcast(d->bcast_ip))
320 if (win_election(work, version,criterion,timeup,name))
322 if (!work->RunningElection)
324 work->needelection = True;
325 work->ElectionCount=0;
330 work->needelection = False;
332 if (work->RunningElection)
334 work->RunningElection = False;
335 DEBUG(3,(">>> Lost election on %s %s <<<\n",
336 work->work_group,inet_ntoa(d->bcast_ip)));
338 /* if we are the master then remove our masterly names */
341 become_nonmaster(d, work);
350 /****************************************************************************
351 checks whether a browser election is to be run on any workgroup
352 ***************************************************************************/
353 BOOL check_elections(void)
355 struct domain_record *d;
356 BOOL run_any_election = False;
358 for (d = domainlist; d; d = d->next)
360 struct work_record *work;
361 for (work = d->workgrouplist; work; work = work->next)
363 run_any_election |= work->RunningElection;
365 if (work->needelection && !work->RunningElection)
367 DEBUG(3,(">>> Starting election on %s %s <<<\n",
368 work->work_group,inet_ntoa(d->bcast_ip)));
369 work->ElectionCount = 0;
370 work->RunningElection = True;
371 work->needelection = False;
375 return run_any_election;