summaryrefslogtreecommitdiff
path: root/source3/nmbd/nmbd_namerelease.c
blob: 4be7396f2e3a3c07cc5694204a4c11d5bb8d0497 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
/* 
   Unix SMB/CIFS implementation.
   NBT netbios routines and daemon - version 2
   Copyright (C) Andrew Tridgell 1994-1998
   Copyright (C) Luke Kenneth Casson Leighton 1994-1998
   Copyright (C) Jeremy Allison 1994-1998
   
   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"

/****************************************************************************
 Deal with a response packet when releasing one of our names.
****************************************************************************/

static void release_name_response(struct subnet_record *subrec,
				  struct response_record *rrec, struct packet_struct *p)
{
	/* 
	 * If we are releasing broadcast, then getting a response is an
	 * error. If we are releasing unicast, then we expect to get a response.
	 */
	struct nmb_packet *nmb = &p->packet.nmb;
	bool bcast = nmb->header.nm_flags.bcast;
	bool success = True;
	struct nmb_name *question_name = &rrec->packet->packet.nmb.question.question_name;
	struct nmb_name *answer_name = &nmb->answers->rr_name;
	struct in_addr released_ip;

	/* Sanity check. Ensure that the answer name in the incoming packet is the
	   same as the requested name in the outgoing packet. */
	if (!nmb_name_equal(question_name, answer_name)) {
		DEBUG(0,("release_name_response: Answer name %s differs from question name %s.\n", 
			 nmb_namestr(answer_name), nmb_namestr(question_name)));
		return;
	}

	if (bcast) {
		/* Someone sent a response to a bcast release? ignore it. */
		return;
	}

	/* Unicast - check to see if the response allows us to release the name. */
	if (nmb->header.rcode != 0) {
		/* Error code - we were told not to release the name ! What now ! */
		success = False;

		DEBUG(0,("release_name_response: WINS server at IP %s rejected our \
name release of name %s with error code %d.\n", 
			 inet_ntoa(p->ip), 
			 nmb_namestr(answer_name), nmb->header.rcode));
	} else if (nmb->header.opcode == NMB_WACK_OPCODE) {
		/* WINS server is telling us to wait. Pretend we didn't get
		   the response but don't send out any more release requests. */

		DEBUG(5,("release_name_response: WACK from WINS server %s in releasing \
name %s on subnet %s.\n", 
			 inet_ntoa(p->ip), nmb_namestr(answer_name), subrec->subnet_name));

		rrec->repeat_count = 0;
		/* How long we should wait for. */
		rrec->repeat_time = p->timestamp + nmb->answers->ttl;
		rrec->num_msgs--;
		return;
	}

	DEBUG(5,("release_name_response: %s in releasing name %s on subnet %s.\n",
		 success ? "success" : "failure", nmb_namestr(answer_name), subrec->subnet_name));
	if (success) {
		putip((char*)&released_ip ,&nmb->answers->rdata[2]);

		if(rrec->success_fn)
			(*(release_name_success_function)rrec->success_fn)(subrec, rrec->userdata, answer_name, released_ip);
		standard_success_release( subrec, rrec->userdata, answer_name, released_ip);
	} else {
		/* We have no standard_fail_release - maybe we should add one ? */
		if (rrec->fail_fn) {
			(*(release_name_fail_function)rrec->fail_fn)(subrec, rrec, answer_name);
		}
	}

	remove_response_record(subrec, rrec);
}

/****************************************************************************
 Deal with a timeout when releasing one of our names.
****************************************************************************/

static void release_name_timeout_response(struct subnet_record *subrec,
					  struct response_record *rrec)
{
	/* a release is *always* considered to be successful when it
	   times out. This doesn't cause problems as if a WINS server
	   doesn't respond and someone else wants the name then the
	   normal WACK/name query from the WINS server will cope */
	struct nmb_packet *sent_nmb = &rrec->packet->packet.nmb;
	bool bcast = sent_nmb->header.nm_flags.bcast;
	struct nmb_name *question_name = &sent_nmb->question.question_name;
	struct in_addr released_ip;

	/* Get the ip address we were trying to release. */
	putip((char*)&released_ip ,&sent_nmb->additional->rdata[2]);

	if (!bcast) {
		/* mark the WINS server temporarily dead */
		wins_srv_died(rrec->packet->ip, released_ip);
	}

	DEBUG(5,("release_name_timeout_response: success in releasing name %s on subnet %s.\n",
		 nmb_namestr(question_name), subrec->subnet_name));

	if (rrec->success_fn) {
		(*(release_name_success_function)rrec->success_fn)(subrec, rrec->userdata, question_name, released_ip);
	}

	standard_success_release( subrec, rrec->userdata, question_name, released_ip);
	remove_response_record(subrec, rrec);
}


/*
  when releasing a name with WINS we need to send the release to each of
  the WINS groups
*/
static void wins_release_name(struct name_record *namerec,
			      release_name_success_function success_fn,
			      release_name_fail_function fail_fn,
			      struct userdata_struct *userdata)			      
{
	int t, i;
	char **wins_tags;

	/* get the list of wins tags - we try to release for each of them */
	wins_tags = wins_srv_tags();

	for (t=0;wins_tags && wins_tags[t]; t++) {
		for (i = 0; i < namerec->data.num_ips; i++) {
			struct in_addr wins_ip = wins_srv_ip_tag(wins_tags[t], namerec->data.ip[i]);

			bool last_one = ((i==namerec->data.num_ips - 1) && !wins_tags[t+1]);
			if (queue_release_name(unicast_subnet,
					       release_name_response,
					       release_name_timeout_response,
					       last_one?success_fn : NULL,
					       last_one? fail_fn : NULL,
					       last_one? userdata : NULL,
					       &namerec->name,
					       namerec->data.nb_flags,
					       namerec->data.ip[i],
					       wins_ip) == NULL) {
				DEBUG(0,("release_name: Failed to send packet trying to release name %s IP %s\n",
					 nmb_namestr(&namerec->name), inet_ntoa(namerec->data.ip[i]) ));
			}
		}
	}

	wins_srv_tags_free(wins_tags);
}


/****************************************************************************
 Try and release one of our names.
****************************************************************************/

void release_name(struct subnet_record *subrec, struct name_record *namerec,
		  release_name_success_function success_fn,
		  release_name_fail_function fail_fn,
		  struct userdata_struct *userdata)
{
	int i;

	/* Ensure it's a SELF name, and in the ACTIVE state. */
	if ((namerec->data.source != SELF_NAME) || !NAME_IS_ACTIVE(namerec)) {
		DEBUG(0,("release_name: Cannot release name %s from subnet %s. Source was %d \n",
			 nmb_namestr(&namerec->name), subrec->subnet_name, namerec->data.source)); 
		return;
	}

	/* Set the name into the deregistering state. */
	namerec->data.nb_flags |= NB_DEREG;

	/* wins releases are a bit different */
	if (subrec == unicast_subnet) {
		wins_release_name(namerec, success_fn, fail_fn, userdata);
		return;
	}

	/*  
	 * Go through and release the name for all known ip addresses.
	 * Only call the success/fail function on the last one (it should
	 * only be done once).
	 */
	for (i = 0; i < namerec->data.num_ips; i++) {
		if (queue_release_name(subrec,
				       release_name_response,
				       release_name_timeout_response,
				       (i == (namerec->data.num_ips - 1)) ? success_fn : NULL,
				       (i == (namerec->data.num_ips - 1)) ? fail_fn : NULL,
				       (i == (namerec->data.num_ips - 1)) ? userdata : NULL,
				       &namerec->name,
				       namerec->data.nb_flags,
				       namerec->data.ip[i],
				       subrec->bcast_ip) == NULL) {
			DEBUG(0,("release_name: Failed to send packet trying to release name %s IP %s\n",
				 nmb_namestr(&namerec->name), inet_ntoa(namerec->data.ip[i]) ));
		}
	}
}