2 Unix SMB/CIFS implementation.
4 low level socket handling for nbt requests
6 Copyright (C) Andrew Tridgell 2005
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 3 of the License, or
11 (at your option) any later version.
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.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>.
23 #include "lib/events/events.h"
24 #include "../lib/util/dlinklist.h"
25 #include "../libcli/nbt/libnbt.h"
26 #include "../libcli/nbt/nbt_proto.h"
27 #include "lib/socket/socket.h"
28 #include "librpc/gen_ndr/ndr_nbt.h"
29 #include "param/param.h"
31 #define NBT_MAX_REPLIES 1000
34 destroy a pending request
36 static int nbt_name_request_destructor(struct nbt_name_request
*req
)
38 if (req
->state
== NBT_REQUEST_SEND
) {
39 DLIST_REMOVE(req
->nbtsock
->send_queue
, req
);
41 if (req
->state
== NBT_REQUEST_WAIT
) {
42 req
->nbtsock
->num_pending
--;
44 if (req
->name_trn_id
!= 0 && !req
->is_reply
) {
45 idr_remove(req
->nbtsock
->idr
, req
->name_trn_id
);
52 if (req
->nbtsock
->send_queue
== NULL
) {
53 TEVENT_FD_NOT_WRITEABLE(req
->nbtsock
->fde
);
55 if (req
->nbtsock
->num_pending
== 0 &&
56 req
->nbtsock
->incoming
.handler
== NULL
) {
57 TEVENT_FD_NOT_READABLE(req
->nbtsock
->fde
);
64 handle send events on a nbt name socket
66 static void nbt_name_socket_send(struct nbt_name_socket
*nbtsock
)
68 struct nbt_name_request
*req
= nbtsock
->send_queue
;
69 TALLOC_CTX
*tmp_ctx
= talloc_new(nbtsock
);
72 while ((req
= nbtsock
->send_queue
)) {
75 len
= req
->encoded
.length
;
76 status
= socket_sendto(nbtsock
->sock
, &req
->encoded
, &len
,
78 if (NT_STATUS_IS_ERR(status
)) goto failed
;
80 if (!NT_STATUS_IS_OK(status
)) {
85 DLIST_REMOVE(nbtsock
->send_queue
, req
);
86 req
->state
= NBT_REQUEST_WAIT
;
90 TEVENT_FD_READABLE(nbtsock
->fde
);
91 nbtsock
->num_pending
++;
95 TEVENT_FD_NOT_WRITEABLE(nbtsock
->fde
);
100 DLIST_REMOVE(nbtsock
->send_queue
, req
);
101 nbt_name_request_destructor(req
);
102 req
->status
= status
;
103 req
->state
= NBT_REQUEST_ERROR
;
104 talloc_free(tmp_ctx
);
107 } else if (req
->is_reply
) {
115 handle a request timeout
117 static void nbt_name_socket_timeout(struct tevent_context
*ev
, struct tevent_timer
*te
,
118 struct timeval t
, void *private_data
)
120 struct nbt_name_request
*req
= talloc_get_type(private_data
,
121 struct nbt_name_request
);
123 if (req
->num_retries
!= 0) {
125 req
->te
= tevent_add_timer(req
->nbtsock
->event_ctx
, req
,
126 timeval_add(&t
, req
->timeout
, 0),
127 nbt_name_socket_timeout
, req
);
128 if (req
->state
!= NBT_REQUEST_SEND
) {
129 req
->state
= NBT_REQUEST_SEND
;
130 DLIST_ADD_END(req
->nbtsock
->send_queue
, req
,
131 struct nbt_name_request
*);
133 TEVENT_FD_WRITEABLE(req
->nbtsock
->fde
);
137 nbt_name_request_destructor(req
);
138 if (req
->num_replies
== 0) {
139 req
->state
= NBT_REQUEST_TIMEOUT
;
140 req
->status
= NT_STATUS_IO_TIMEOUT
;
142 req
->state
= NBT_REQUEST_DONE
;
143 req
->status
= NT_STATUS_OK
;
147 } else if (req
->is_reply
) {
155 handle recv events on a nbt name socket
157 static void nbt_name_socket_recv(struct nbt_name_socket
*nbtsock
)
159 TALLOC_CTX
*tmp_ctx
= talloc_new(nbtsock
);
161 enum ndr_err_code ndr_err
;
162 struct socket_address
*src
;
165 struct nbt_name_packet
*packet
;
166 struct nbt_name_request
*req
;
168 status
= socket_pending(nbtsock
->sock
, &dsize
);
169 if (!NT_STATUS_IS_OK(status
)) {
170 talloc_free(tmp_ctx
);
174 blob
= data_blob_talloc(tmp_ctx
, NULL
, dsize
);
175 if (blob
.data
== NULL
) {
176 talloc_free(tmp_ctx
);
180 status
= socket_recvfrom(nbtsock
->sock
, blob
.data
, blob
.length
, &nread
,
182 if (!NT_STATUS_IS_OK(status
)) {
183 talloc_free(tmp_ctx
);
187 packet
= talloc(tmp_ctx
, struct nbt_name_packet
);
188 if (packet
== NULL
) {
189 talloc_free(tmp_ctx
);
193 /* parse the request */
194 ndr_err
= ndr_pull_struct_blob(&blob
, packet
, packet
,
195 (ndr_pull_flags_fn_t
)ndr_pull_nbt_name_packet
);
196 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err
)) {
197 status
= ndr_map_error2ntstatus(ndr_err
);
198 DEBUG(2,("Failed to parse incoming NBT name packet - %s\n",
200 talloc_free(tmp_ctx
);
205 DEBUG(10,("Received nbt packet of length %d from %s:%d\n",
206 (int)blob
.length
, src
->addr
, src
->port
));
207 NDR_PRINT_DEBUG(nbt_name_packet
, packet
);
210 /* if its not a reply then pass it off to the incoming request
212 if (!(packet
->operation
& NBT_FLAG_REPLY
)) {
213 if (nbtsock
->incoming
.handler
) {
214 nbtsock
->incoming
.handler(nbtsock
, packet
, src
);
216 talloc_free(tmp_ctx
);
220 /* find the matching request */
221 req
= (struct nbt_name_request
*)idr_find(nbtsock
->idr
,
222 packet
->name_trn_id
);
224 if (nbtsock
->unexpected
.handler
) {
225 nbtsock
->unexpected
.handler(nbtsock
, packet
, src
);
227 DEBUG(10,("Failed to match request for incoming name packet id 0x%04x on %p\n",
228 packet
->name_trn_id
, nbtsock
));
230 talloc_free(tmp_ctx
);
234 talloc_steal(req
, packet
);
235 talloc_steal(req
, src
);
236 talloc_free(tmp_ctx
);
237 nbt_name_socket_handle_response_packet(req
, packet
, src
);
240 void nbt_name_socket_handle_response_packet(struct nbt_name_request
*req
,
241 struct nbt_name_packet
*packet
,
242 struct socket_address
*src
)
244 /* if this is a WACK response, this we need to go back to waiting,
245 but perhaps increase the timeout */
246 if ((packet
->operation
& NBT_OPCODE
) == NBT_OPCODE_WACK
) {
248 if (req
->received_wack
|| packet
->ancount
< 1) {
249 nbt_name_request_destructor(req
);
250 req
->status
= NT_STATUS_INVALID_NETWORK_RESPONSE
;
251 req
->state
= NBT_REQUEST_ERROR
;
254 talloc_free(req
->te
);
255 /* we know we won't need any more retries - the server
256 has received our request */
257 req
->num_retries
= 0;
258 req
->received_wack
= true;
260 * there is a timeout in the packet,
261 * it is 5 + 4 * num_old_addresses
263 * although w2k3 screws it up
264 * and uses num_old_addresses = 0
266 * so we better fallback to the maximum
267 * of num_old_addresses = 25 if we got
268 * a timeout of less than 9s (5 + 4*1)
269 * or more than 105s (5 + 4*25).
271 ttl
= packet
->answers
[0].ttl
;
272 if ((ttl
< (5 + 4*1)) || (ttl
> (5 + 4*25))) {
276 req
->te
= tevent_add_timer(req
->nbtsock
->event_ctx
, req
,
277 timeval_current_ofs(req
->timeout
, 0),
278 nbt_name_socket_timeout
, req
);
283 req
->replies
= talloc_realloc(req
, req
->replies
, struct nbt_name_reply
, req
->num_replies
+1);
284 if (req
->replies
== NULL
) {
285 nbt_name_request_destructor(req
);
286 req
->state
= NBT_REQUEST_ERROR
;
287 req
->status
= NT_STATUS_NO_MEMORY
;
291 talloc_steal(req
, src
);
292 req
->replies
[req
->num_replies
].dest
= src
;
293 talloc_steal(req
, packet
);
294 req
->replies
[req
->num_replies
].packet
= packet
;
297 /* if we don't want multiple replies then we are done */
298 if (req
->allow_multiple_replies
&&
299 req
->num_replies
< NBT_MAX_REPLIES
) {
303 nbt_name_request_destructor(req
);
304 req
->state
= NBT_REQUEST_DONE
;
305 req
->status
= NT_STATUS_OK
;
314 handle fd events on a nbt_name_socket
316 static void nbt_name_socket_handler(struct tevent_context
*ev
, struct tevent_fd
*fde
,
317 uint16_t flags
, void *private_data
)
319 struct nbt_name_socket
*nbtsock
= talloc_get_type(private_data
,
320 struct nbt_name_socket
);
321 if (flags
& TEVENT_FD_WRITE
) {
322 nbt_name_socket_send(nbtsock
);
324 if (flags
& TEVENT_FD_READ
) {
325 nbt_name_socket_recv(nbtsock
);
331 initialise a nbt_name_socket. The event_ctx is optional, if provided
332 then operations will use that event context
334 _PUBLIC_
struct nbt_name_socket
*nbt_name_socket_init(TALLOC_CTX
*mem_ctx
,
335 struct tevent_context
*event_ctx
)
337 struct nbt_name_socket
*nbtsock
;
340 nbtsock
= talloc(mem_ctx
, struct nbt_name_socket
);
341 if (nbtsock
== NULL
) goto failed
;
343 nbtsock
->event_ctx
= event_ctx
;
344 if (nbtsock
->event_ctx
== NULL
) goto failed
;
346 status
= socket_create("ip", SOCKET_TYPE_DGRAM
, &nbtsock
->sock
, 0);
347 if (!NT_STATUS_IS_OK(status
)) goto failed
;
349 socket_set_option(nbtsock
->sock
, "SO_BROADCAST", "1");
351 talloc_steal(nbtsock
, nbtsock
->sock
);
353 nbtsock
->idr
= idr_init(nbtsock
);
354 if (nbtsock
->idr
== NULL
) goto failed
;
356 nbtsock
->send_queue
= NULL
;
357 nbtsock
->num_pending
= 0;
358 nbtsock
->incoming
.handler
= NULL
;
359 nbtsock
->unexpected
.handler
= NULL
;
361 nbtsock
->fde
= tevent_add_fd(nbtsock
->event_ctx
, nbtsock
,
362 socket_get_fd(nbtsock
->sock
), 0,
363 nbt_name_socket_handler
, nbtsock
);
368 talloc_free(nbtsock
);
373 send off a nbt name request
375 struct nbt_name_request
*nbt_name_request_send(struct nbt_name_socket
*nbtsock
,
376 struct socket_address
*dest
,
377 struct nbt_name_packet
*request
,
378 int timeout
, int retries
,
379 bool allow_multiple_replies
)
381 struct nbt_name_request
*req
;
383 enum ndr_err_code ndr_err
;
385 req
= talloc_zero(nbtsock
, struct nbt_name_request
);
386 if (req
== NULL
) goto failed
;
388 req
->nbtsock
= nbtsock
;
389 req
->allow_multiple_replies
= allow_multiple_replies
;
390 req
->state
= NBT_REQUEST_SEND
;
391 req
->is_reply
= false;
392 req
->timeout
= timeout
;
393 req
->num_retries
= retries
;
395 if (talloc_reference(req
, dest
) == NULL
) goto failed
;
397 /* we select a random transaction id unless the user supplied one */
398 if (request
->name_trn_id
== 0) {
399 id
= idr_get_new_random(req
->nbtsock
->idr
, req
, UINT16_MAX
);
401 if (idr_find(req
->nbtsock
->idr
, request
->name_trn_id
)) goto failed
;
402 id
= idr_get_new_above(req
->nbtsock
->idr
, req
, request
->name_trn_id
,
405 if (id
== -1) goto failed
;
407 request
->name_trn_id
= id
;
408 req
->name_trn_id
= id
;
410 req
->te
= tevent_add_timer(nbtsock
->event_ctx
, req
,
411 timeval_current_ofs(req
->timeout
, 0),
412 nbt_name_socket_timeout
, req
);
414 talloc_set_destructor(req
, nbt_name_request_destructor
);
416 ndr_err
= ndr_push_struct_blob(&req
->encoded
, req
,
418 (ndr_push_flags_fn_t
)ndr_push_nbt_name_packet
);
419 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err
)) goto failed
;
421 DLIST_ADD_END(nbtsock
->send_queue
, req
, struct nbt_name_request
*);
424 DEBUG(10,("Queueing nbt packet to %s:%d\n",
425 req
->dest
->addr
, req
->dest
->port
));
426 NDR_PRINT_DEBUG(nbt_name_packet
, request
);
429 TEVENT_FD_WRITEABLE(nbtsock
->fde
);
440 send off a nbt name reply
442 _PUBLIC_ NTSTATUS
nbt_name_reply_send(struct nbt_name_socket
*nbtsock
,
443 struct socket_address
*dest
,
444 struct nbt_name_packet
*request
)
446 struct nbt_name_request
*req
;
447 enum ndr_err_code ndr_err
;
449 req
= talloc_zero(nbtsock
, struct nbt_name_request
);
450 NT_STATUS_HAVE_NO_MEMORY(req
);
452 req
->nbtsock
= nbtsock
;
454 if (talloc_reference(req
, dest
) == NULL
) goto failed
;
455 req
->state
= NBT_REQUEST_SEND
;
456 req
->is_reply
= true;
458 talloc_set_destructor(req
, nbt_name_request_destructor
);
461 NDR_PRINT_DEBUG(nbt_name_packet
, request
);
464 ndr_err
= ndr_push_struct_blob(&req
->encoded
, req
,
466 (ndr_push_flags_fn_t
)ndr_push_nbt_name_packet
);
467 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err
)) {
469 return ndr_map_error2ntstatus(ndr_err
);
472 DLIST_ADD_END(nbtsock
->send_queue
, req
, struct nbt_name_request
*);
474 TEVENT_FD_WRITEABLE(nbtsock
->fde
);
480 return NT_STATUS_NO_MEMORY
;
484 wait for a nbt request to complete
486 NTSTATUS
nbt_name_request_recv(struct nbt_name_request
*req
)
488 if (!req
) return NT_STATUS_NO_MEMORY
;
490 while (req
->state
< NBT_REQUEST_DONE
) {
491 if (tevent_loop_once(req
->nbtsock
->event_ctx
) != 0) {
492 req
->state
= NBT_REQUEST_ERROR
;
493 req
->status
= NT_STATUS_UNEXPECTED_NETWORK_ERROR
;
502 setup a handler for incoming requests
504 _PUBLIC_ NTSTATUS
nbt_set_incoming_handler(struct nbt_name_socket
*nbtsock
,
505 void (*handler
)(struct nbt_name_socket
*, struct nbt_name_packet
*,
506 struct socket_address
*),
509 nbtsock
->incoming
.handler
= handler
;
510 nbtsock
->incoming
.private_data
= private_data
;
511 TEVENT_FD_READABLE(nbtsock
->fde
);
516 setup a handler for unexpected requests
518 NTSTATUS
nbt_set_unexpected_handler(struct nbt_name_socket
*nbtsock
,
519 void (*handler
)(struct nbt_name_socket
*, struct nbt_name_packet
*,
520 struct socket_address
*),
523 nbtsock
->unexpected
.handler
= handler
;
524 nbtsock
->unexpected
.private_data
= private_data
;
525 TEVENT_FD_READABLE(nbtsock
->fde
);
530 turn a NBT rcode into a NTSTATUS
532 _PUBLIC_ NTSTATUS
nbt_rcode_to_ntstatus(uint8_t rcode
)
536 enum nbt_rcode rcode
;
539 { NBT_RCODE_FMT
, NT_STATUS_INVALID_PARAMETER
},
540 { NBT_RCODE_SVR
, NT_STATUS_SERVER_DISABLED
},
541 { NBT_RCODE_NAM
, NT_STATUS_OBJECT_NAME_NOT_FOUND
},
542 { NBT_RCODE_IMP
, NT_STATUS_NOT_SUPPORTED
},
543 { NBT_RCODE_RFS
, NT_STATUS_ACCESS_DENIED
},
544 { NBT_RCODE_ACT
, NT_STATUS_ADDRESS_ALREADY_EXISTS
},
545 { NBT_RCODE_CFT
, NT_STATUS_CONFLICTING_ADDRESSES
}
547 for (i
=0;i
<ARRAY_SIZE(map
);i
++) {
548 if (map
[i
].rcode
== rcode
) {
549 return map
[i
].status
;
552 return NT_STATUS_UNSUCCESSFUL
;