summaryrefslogtreecommitdiff
path: root/source4/nbt_server/packet.c
blob: c1e0c4411bfb516548b0b36826139d3b9c4bce3c (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
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
/* 
   Unix SMB/CIFS implementation.

   packet utility functions

   Copyright (C) Andrew Tridgell	2005
   
   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 2 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, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "includes.h"
#include "dlinklist.h"
#include "nbt_server/nbt_server.h"

/*
  we received a badly formed packet - log it
*/
void nbtd_bad_packet(struct nbt_name_packet *packet, 
		     const char *src_address, const char *reason)
{
	DEBUG(2,("nbtd: bad packet '%s' from %s\n", reason, src_address));
	if (DEBUGLVL(5)) {
		NDR_PRINT_DEBUG(nbt_name_packet, packet);		
	}
}


/*
  see if an incoming packet is a broadcast packet from one of our own
  interfaces
*/
BOOL nbtd_self_packet(struct nbt_name_socket *nbtsock, 
		      struct nbt_name_packet *packet, 
		      const char *src_address, int src_port)
{
	struct nbtd_interface *iface = talloc_get_type(nbtsock->incoming.private, 
						       struct nbtd_interface);
	struct nbtd_server *nbtsrv = iface->nbtsrv;
	
	/* if its not a broadcast then its not considered a self packet */
	if (!(packet->operation & NBT_FLAG_BROADCAST)) {
		return False;
	}

	/* if its not from the nbt port, then it wasn't a broadcast from us */
	if (src_port != lp_nbt_port()) {
		return False;
	}

	/* this uses the fact that iface->nbtsock is our non-broadcast
	   listen address */
	if (iface->nbtsock == nbtsock &&
	    iface != iface->nbtsrv->bcast_interface) {
		return False;
	}

	/* we have to loop over our interface list, seeing if its from
	   one of our own interfaces */
	for (iface=nbtsrv->interfaces;iface;iface=iface->next) {
		if (strcmp(src_address, iface->ip_address) == 0) {
			return True;
		}
	}

	return False;
}


/*
  send a name query reply
*/
void nbtd_name_query_reply(struct nbt_name_socket *nbtsock, 
			   struct nbt_name_packet *request_packet, 
			   const char *src_address, int src_port,
			   struct nbt_name *name, uint32_t ttl,
			   uint16_t nb_flags, const char **addresses)
{
	struct nbt_name_packet *packet;
	size_t num_addresses = str_list_length(addresses);
	struct nbtd_interface *iface = talloc_get_type(nbtsock->incoming.private, 
						       struct nbtd_interface);
	struct nbtd_server *nbtsrv = iface->nbtsrv;
	int i;

	if (num_addresses == 0) {
		DEBUG(3,("No addresses in name query reply - failing\n"));
		return;
	}

	packet = talloc_zero(nbtsock, struct nbt_name_packet);
	if (packet == NULL) return;

	packet->name_trn_id = request_packet->name_trn_id;
	packet->ancount = 1;
	packet->operation = 
		NBT_FLAG_REPLY | 
		NBT_OPCODE_QUERY | 
		NBT_FLAG_AUTHORITIVE |
		NBT_FLAG_RECURSION_DESIRED |
		NBT_FLAG_RECURSION_AVAIL;

	packet->answers = talloc_array(packet, struct nbt_res_rec, 1);
	if (packet->answers == NULL) goto failed;

	packet->answers[0].name     = *name;
	packet->answers[0].rr_type  = NBT_QTYPE_NETBIOS;
	packet->answers[0].rr_class = NBT_QCLASS_IP;
	packet->answers[0].ttl      = ttl;
	packet->answers[0].rdata.netbios.length = num_addresses*6;
	packet->answers[0].rdata.netbios.addresses = 
		talloc_array(packet->answers, struct nbt_rdata_address, num_addresses);
	if (packet->answers[0].rdata.netbios.addresses == NULL) goto failed;

	for (i=0;i<num_addresses;i++) {
		struct nbt_rdata_address *addr = 
			&packet->answers[0].rdata.netbios.addresses[i];
		addr->nb_flags = nb_flags;
		addr->ipaddr = talloc_strdup(packet->answers, addresses[i]);
		if (addr->ipaddr == NULL) goto failed;
	}

	DEBUG(7,("Sending name query reply for %s at %s to %s:%d\n", 
		 nbt_name_string(packet, name), addresses[0], src_address, src_port));
	
	nbtsrv->stats.total_sent++;
	nbt_name_reply_send(nbtsock, src_address, src_port, packet);

failed:
	talloc_free(packet);
}


/*
  send a negative name query reply
*/
void nbtd_negative_name_query_reply(struct nbt_name_socket *nbtsock, 
				    struct nbt_name_packet *request_packet, 
				    const char *src_address, int src_port)
{
	struct nbt_name_packet *packet;
	struct nbt_name *name = &request_packet->questions[0].name;
	struct nbtd_interface *iface = talloc_get_type(nbtsock->incoming.private, 
						       struct nbtd_interface);
	struct nbtd_server *nbtsrv = iface->nbtsrv;

	packet = talloc_zero(nbtsock, struct nbt_name_packet);
	if (packet == NULL) return;

	packet->name_trn_id = request_packet->name_trn_id;
	packet->ancount = 1;
	packet->operation = 
		NBT_FLAG_REPLY | 
		NBT_OPCODE_QUERY | 
		NBT_FLAG_AUTHORITIVE |
		NBT_RCODE_NAM;

	packet->answers = talloc_array(packet, struct nbt_res_rec, 1);
	if (packet->answers == NULL) goto failed;

	packet->answers[0].name      = *name;
	packet->answers[0].rr_type   = NBT_QTYPE_NULL;
	packet->answers[0].rr_class  = NBT_QCLASS_IP;
	packet->answers[0].ttl       = 0;
	ZERO_STRUCT(packet->answers[0].rdata);

	DEBUG(7,("Sending negative name query reply for %s to %s:%d\n", 
		 nbt_name_string(packet, name), src_address, src_port));
	
	nbtsrv->stats.total_sent++;
	nbt_name_reply_send(nbtsock, src_address, src_port, packet);

failed:
	talloc_free(packet);
}

/*
  send a name registration reply
*/
void nbtd_name_registration_reply(struct nbt_name_socket *nbtsock, 
				  struct nbt_name_packet *request_packet, 
				  const char *src_address, int src_port,
				  uint8_t rcode)
{
	struct nbt_name_packet *packet;
	struct nbt_name *name = &request_packet->questions[0].name;
	struct nbtd_interface *iface = talloc_get_type(nbtsock->incoming.private, 
						       struct nbtd_interface);
	struct nbtd_server *nbtsrv = iface->nbtsrv;

	packet = talloc_zero(nbtsock, struct nbt_name_packet);
	if (packet == NULL) return;

	packet->name_trn_id = request_packet->name_trn_id;
	packet->ancount = 1;
	packet->operation = 
		NBT_FLAG_REPLY | 
		NBT_OPCODE_REGISTER |
		NBT_FLAG_AUTHORITIVE |
		NBT_FLAG_RECURSION_DESIRED |
		NBT_FLAG_RECURSION_AVAIL |
		rcode;
	
	packet->answers = talloc_array(packet, struct nbt_res_rec, 1);
	if (packet->answers == NULL) goto failed;

	packet->answers[0].name     = *name;
	packet->answers[0].rr_type  = NBT_QTYPE_NETBIOS;
	packet->answers[0].rr_class = NBT_QCLASS_IP;
	packet->answers[0].ttl      = request_packet->additional[0].ttl;
	packet->answers[0].rdata    = request_packet->additional[0].rdata;

	DEBUG(7,("Sending %s name registration reply for %s to %s:%d\n", 
		 rcode==0?"positive":"negative",
		 nbt_name_string(packet, name), src_address, src_port));
	
	nbtsrv->stats.total_sent++;
	nbt_name_reply_send(nbtsock, src_address, src_port, packet);

failed:
	talloc_free(packet);
}


/*
  send a name release reply
*/
void nbtd_name_release_reply(struct nbt_name_socket *nbtsock, 
			     struct nbt_name_packet *request_packet, 
			     const char *src_address, int src_port,
			     uint8_t rcode)
{
	struct nbt_name_packet *packet;
	struct nbt_name *name = &request_packet->questions[0].name;
	struct nbtd_interface *iface = talloc_get_type(nbtsock->incoming.private, 
						       struct nbtd_interface);
	struct nbtd_server *nbtsrv = iface->nbtsrv;

	packet = talloc_zero(nbtsock, struct nbt_name_packet);
	if (packet == NULL) return;

	packet->name_trn_id = request_packet->name_trn_id;
	packet->ancount = 1;
	packet->operation = 
		NBT_FLAG_REPLY | 
		NBT_OPCODE_RELEASE |
		NBT_FLAG_AUTHORITIVE |
		rcode;
	
	packet->answers = talloc_array(packet, struct nbt_res_rec, 1);
	if (packet->answers == NULL) goto failed;

	packet->answers[0].name     = *name;
	packet->answers[0].rr_type  = NBT_QTYPE_NETBIOS;
	packet->answers[0].rr_class = NBT_QCLASS_IP;
	packet->answers[0].ttl      = request_packet->additional[0].ttl;
	packet->answers[0].rdata    = request_packet->additional[0].rdata;

	DEBUG(7,("Sending %s name release reply for %s to %s:%d\n", 
		 rcode==0?"positive":"negative",
		 nbt_name_string(packet, name), src_address, src_port));
	
	nbtsrv->stats.total_sent++;
	nbt_name_reply_send(nbtsock, src_address, src_port, packet);

failed:
	talloc_free(packet);
}


/*
  send a WACK reply
*/
void nbtd_wack_reply(struct nbt_name_socket *nbtsock, 
		     struct nbt_name_packet *request_packet, 
		     const char *src_address, int src_port,
		     uint32_t ttl)
{
	struct nbt_name_packet *packet;
	struct nbt_name *name = &request_packet->questions[0].name;
	struct nbtd_interface *iface = talloc_get_type(nbtsock->incoming.private, 
						       struct nbtd_interface);
	struct nbtd_server *nbtsrv = iface->nbtsrv;

	packet = talloc_zero(nbtsock, struct nbt_name_packet);
	if (packet == NULL) return;

	packet->name_trn_id = request_packet->name_trn_id;
	packet->ancount = 1;
	packet->operation = 
		NBT_FLAG_REPLY | 
		NBT_OPCODE_WACK |
		NBT_FLAG_AUTHORITIVE;
	
	packet->answers = talloc_array(packet, struct nbt_res_rec, 1);
	if (packet->answers == NULL) goto failed;

	packet->answers[0].name              = *name;
	packet->answers[0].rr_type           = NBT_QTYPE_NETBIOS;
	packet->answers[0].rr_class          = NBT_QCLASS_IP;
	packet->answers[0].ttl               = ttl;
	packet->answers[0].rdata.data.length = 2;
	packet->answers[0].rdata.data.data   = talloc_size(packet, 2);
	if (packet->answers[0].rdata.data.data == NULL) goto failed;
	RSSVAL(packet->answers[0].rdata.data.data, 0, request_packet->operation);

	DEBUG(7,("Sending WACK reply for %s to %s:%d\n", 
		 nbt_name_string(packet, name), src_address, src_port));
	
	nbtsrv->stats.total_sent++;
	nbt_name_reply_send(nbtsock, src_address, src_port, packet);

failed:
	talloc_free(packet);
}