source: branches/samba-3.0/source/nmbd/nmbd_namequery.c

Last change on this file was 1, checked in by Paul Smedley, 18 years ago

Initial code import
File size: 9.3 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 1994-2003
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 2 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, write to the Free Software
20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21
22*/
23
24#include "includes.h"
25
26/****************************************************************************
27 Deal with a response packet when querying a name.
28****************************************************************************/
29
30static void query_name_response( struct subnet_record *subrec,
31 struct response_record *rrec,
32 struct packet_struct *p)
33{
34 struct nmb_packet *nmb = &p->packet.nmb;
35 BOOL success = False;
36 struct nmb_name *question_name = &rrec->packet->packet.nmb.question.question_name;
37 struct in_addr answer_ip;
38
39 zero_ip(&answer_ip);
40
41 /* Ensure we don't retry the query but leave the response record cleanup
42 to the timeout code. We may get more answer responses in which case
43 we should mark the name in conflict.. */
44 rrec->repeat_count = 0;
45
46 if(rrec->num_msgs == 1) {
47 /* This is the first response. */
48
49 if(nmb->header.opcode == NMB_WACK_OPCODE) {
50 /* WINS server is telling us to wait. Pretend we didn't get
51 the response but don't send out any more query requests. */
52
53 if( DEBUGLVL( 5 ) ) {
54 dbgtext( "query_name_response: " );
55 dbgtext( "WACK from WINS server %s ", inet_ntoa(p->ip) );
56 dbgtext( "in querying name %s ", nmb_namestr(question_name) );
57 dbgtext( "on subnet %s.\n", subrec->subnet_name );
58 }
59
60 rrec->repeat_count = 0;
61 /* How long we should wait for. */
62 if (nmb->answers) {
63 rrec->repeat_time = p->timestamp + nmb->answers->ttl;
64 } else {
65 /* No answer - this is probably a corrupt
66 packet.... */
67 DEBUG(0,("query_name_response: missing answer record in "
68 "NMB_WACK_OPCODE response.\n"));
69 rrec->repeat_time = p->timestamp + 10;
70 }
71 rrec->num_msgs--;
72 return;
73 } else if(nmb->header.rcode != 0) {
74
75 success = False;
76
77 if( DEBUGLVL( 5 ) ) {
78 dbgtext( "query_name_response: On subnet %s ", subrec->subnet_name );
79 dbgtext( "- negative response from IP %s ", inet_ntoa(p->ip) );
80 dbgtext( "for name %s. ", nmb_namestr(question_name) );
81 dbgtext( "Error code was %d.\n", nmb->header.rcode );
82 }
83 } else {
84 if (!nmb->answers) {
85 dbgtext( "query_name_response: On subnet %s ", subrec->subnet_name );
86 dbgtext( "IP %s ", inet_ntoa(p->ip) );
87 dbgtext( "returned a success response with no answer\n" );
88 return;
89 }
90
91 success = True;
92
93 putip((char *)&answer_ip,&nmb->answers->rdata[2]);
94
95 if( DEBUGLVL( 5 ) ) {
96 dbgtext( "query_name_response: On subnet %s ", subrec->subnet_name );
97 dbgtext( "- positive response from IP %s ", inet_ntoa(p->ip) );
98 dbgtext( "for name %s. ", nmb_namestr(question_name) );
99 dbgtext( "IP of that name is %s\n", inet_ntoa(answer_ip) );
100 }
101
102 /* Interestingly, we could add these names to our namelists, and
103 change nmbd to a model that checked its own name cache first,
104 before sending out a query. This is a task for another day, though.
105 */
106 }
107 } else if( rrec->num_msgs > 1) {
108
109 if( DEBUGLVL( 0 ) ) {
110 if (nmb->answers)
111 putip( (char *)&answer_ip, &nmb->answers->rdata[2] );
112 dbgtext( "query_name_response: " );
113 dbgtext( "Multiple (%d) responses ", rrec->num_msgs );
114 dbgtext( "received for a query on subnet %s ", subrec->subnet_name );
115 dbgtext( "for name %s.\nThis response ", nmb_namestr(question_name) );
116 dbgtext( "was from IP %s, reporting ", inet_ntoa(p->ip) );
117 dbgtext( "an IP address of %s.\n", inet_ntoa(answer_ip) );
118 }
119
120 /* We have already called the success or fail function, so we
121 don't call again here. Leave the response record around in
122 case we get more responses. */
123
124 return;
125 }
126
127 if(success && rrec->success_fn)
128 (*(query_name_success_function)rrec->success_fn)(subrec, rrec->userdata, question_name, answer_ip, nmb->answers);
129 else if( rrec->fail_fn)
130 (*(query_name_fail_function)rrec->fail_fn)(subrec, rrec, question_name, nmb->header.rcode);
131
132}
133
134/****************************************************************************
135 Deal with a timeout when querying a name.
136****************************************************************************/
137
138static void query_name_timeout_response(struct subnet_record *subrec,
139 struct response_record *rrec)
140{
141 struct nmb_packet *sent_nmb = &rrec->packet->packet.nmb;
142 /* We can only fail here, never succeed. */
143 BOOL failed = True;
144 struct nmb_name *question_name = &sent_nmb->question.question_name;
145
146 if(rrec->num_msgs != 0) {
147 /* We got at least one response, and have called the success/fail
148 function already. */
149
150 failed = False;
151 }
152
153 if(failed) {
154 if( DEBUGLVL( 5 ) ) {
155 dbgtext( "query_name_timeout_response: No response to " );
156 dbgtext( "query for name %s ", nmb_namestr(question_name) );
157 dbgtext( "on subnet %s.\n", subrec->subnet_name );
158 }
159
160 if(rrec->fail_fn)
161 (*(query_name_fail_function)rrec->fail_fn)(subrec, rrec, question_name, 0);
162 }
163
164 remove_response_record(subrec, rrec);
165}
166
167/****************************************************************************
168 Lookup a name on our local namelists. We check the lmhosts file first. If the
169 name is not there we look for the name on the given subnet.
170****************************************************************************/
171
172static BOOL query_local_namelists(struct subnet_record *subrec, struct nmb_name *nmbname,
173 struct name_record **namerecp)
174{
175 struct name_record *namerec;
176
177 *namerecp = NULL;
178
179 if(find_name_in_lmhosts(nmbname, namerecp))
180 return True;
181
182 if((namerec = find_name_on_subnet(subrec, nmbname, FIND_ANY_NAME))==NULL)
183 return False;
184
185 if( NAME_IS_ACTIVE(namerec) && ( (namerec->data.source == SELF_NAME) || (namerec->data.source == LMHOSTS_NAME) ) ) {
186 *namerecp = namerec;
187 return True;
188 }
189 return False;
190}
191
192/****************************************************************************
193 Try and query for a name.
194****************************************************************************/
195
196BOOL query_name(struct subnet_record *subrec, const char *name, int type,
197 query_name_success_function success_fn,
198 query_name_fail_function fail_fn,
199 struct userdata_struct *userdata)
200{
201 struct nmb_name nmbname;
202 struct name_record *namerec;
203
204 make_nmb_name(&nmbname, name, type);
205
206 /*
207 * We need to check our local namelists first.
208 * It may be an magic name, lmhosts name or just
209 * a name we have registered.
210 */
211
212 if(query_local_namelists(subrec, &nmbname, &namerec) == True) {
213 struct res_rec rrec;
214 int i;
215
216 memset((char *)&rrec, '\0', sizeof(struct res_rec));
217
218 /* Fake up the needed res_rec just in case it's used. */
219 rrec.rr_name = nmbname;
220 rrec.rr_type = RR_TYPE_NB;
221 rrec.rr_class = RR_CLASS_IN;
222 rrec.ttl = PERMANENT_TTL;
223 rrec.rdlength = namerec->data.num_ips * 6;
224 if(rrec.rdlength > MAX_DGRAM_SIZE) {
225 if( DEBUGLVL( 0 ) ) {
226 dbgtext( "query_name: nmbd internal error - " );
227 dbgtext( "there are %d ip addresses ", namerec->data.num_ips );
228 dbgtext( "for name %s.\n", nmb_namestr(&nmbname) );
229 }
230 return False;
231 }
232
233 for( i = 0; i < namerec->data.num_ips; i++) {
234 set_nb_flags( &rrec.rdata[i*6], namerec->data.nb_flags );
235 putip( &rrec.rdata[(i*6) + 2], (char *)&namerec->data.ip[i]);
236 }
237
238 /* Call the success function directly. */
239 if(success_fn)
240 (*(query_name_success_function)success_fn)(subrec, userdata, &nmbname, namerec->data.ip[0], &rrec);
241 return False;
242 }
243
244 if(queue_query_name( subrec, query_name_response, query_name_timeout_response, success_fn, fail_fn, userdata, &nmbname) == NULL) {
245 if( DEBUGLVL( 0 ) ) {
246 dbgtext( "query_name: Failed to send packet " );
247 dbgtext( "trying to query name %s\n", nmb_namestr(&nmbname) );
248 }
249 return True;
250 }
251 return False;
252}
253
254/****************************************************************************
255 Try and query for a name from nmbd acting as a WINS server.
256****************************************************************************/
257
258BOOL query_name_from_wins_server(struct in_addr ip_to,
259 const char *name, int type,
260 query_name_success_function success_fn,
261 query_name_fail_function fail_fn,
262 struct userdata_struct *userdata)
263{
264 struct nmb_name nmbname;
265
266 make_nmb_name(&nmbname, name, type);
267
268 if(queue_query_name_from_wins_server( ip_to, query_name_response, query_name_timeout_response, success_fn, fail_fn, userdata, &nmbname) == NULL) {
269 if( DEBUGLVL( 0 ) ) {
270 dbgtext( "query_name_from_wins_server: Failed to send packet " );
271 dbgtext( "trying to query name %s\n", nmb_namestr(&nmbname) );
272 }
273 return True;
274 }
275 return False;
276}
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