Attempt to fix the merged build
[jra/samba/.git] / libcli / nbt / nbtsocket.c
1 /*
2    Unix SMB/CIFS implementation.
3
4    low level socket handling for nbt requests
5
6    Copyright (C) Andrew Tridgell 2005
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 3 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, see <http://www.gnu.org/licenses/>.
20 */
21
22 #include "includes.h"
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"
30
31 #define NBT_MAX_REPLIES 1000
32
33 /*
34   destroy a pending request
35 */
36 static int nbt_name_request_destructor(struct nbt_name_request *req)
37 {
38         if (req->state == NBT_REQUEST_SEND) {
39                 DLIST_REMOVE(req->nbtsock->send_queue, req);
40         }
41         if (req->state == NBT_REQUEST_WAIT) {
42                 req->nbtsock->num_pending--;
43         }
44         if (req->name_trn_id != 0 && !req->is_reply) {
45                 idr_remove(req->nbtsock->idr, req->name_trn_id);
46                 req->name_trn_id = 0;
47         }
48         if (req->te) {
49                 talloc_free(req->te);
50                 req->te = NULL;
51         }
52         if (req->nbtsock->send_queue == NULL) {
53                 EVENT_FD_NOT_WRITEABLE(req->nbtsock->fde);
54         }
55         if (req->nbtsock->num_pending == 0 &&
56             req->nbtsock->incoming.handler == NULL) {
57                 EVENT_FD_NOT_READABLE(req->nbtsock->fde);
58         }
59         return 0;
60 }
61
62
63 /*
64   handle send events on a nbt name socket
65 */
66 static void nbt_name_socket_send(struct nbt_name_socket *nbtsock)
67 {
68         struct nbt_name_request *req = nbtsock->send_queue;
69         TALLOC_CTX *tmp_ctx = talloc_new(nbtsock);
70         NTSTATUS status;
71
72         while ((req = nbtsock->send_queue)) {
73                 size_t len;
74
75                 len = req->encoded.length;
76                 status = socket_sendto(nbtsock->sock, &req->encoded, &len,
77                                        req->dest);
78                 if (NT_STATUS_IS_ERR(status)) goto failed;
79
80                 if (!NT_STATUS_IS_OK(status)) {
81                         talloc_free(tmp_ctx);
82                         return;
83                 }
84
85                 DLIST_REMOVE(nbtsock->send_queue, req);
86                 req->state = NBT_REQUEST_WAIT;
87                 if (req->is_reply) {
88                         talloc_free(req);
89                 } else {
90                         EVENT_FD_READABLE(nbtsock->fde);
91                         nbtsock->num_pending++;
92                 }
93         }
94
95         EVENT_FD_NOT_WRITEABLE(nbtsock->fde);
96         talloc_free(tmp_ctx);
97         return;
98
99 failed:
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);
105         if (req->async.fn) {
106                 req->async.fn(req);
107         } else if (req->is_reply) {
108                 talloc_free(req);
109         }
110         return;
111 }
112
113
114 /*
115   handle a request timeout
116 */
117 static void nbt_name_socket_timeout(struct tevent_context *ev, struct tevent_timer *te,
118                                     struct timeval t, void *private)
119 {
120         struct nbt_name_request *req = talloc_get_type(private,
121                                                        struct nbt_name_request);
122
123         if (req->num_retries != 0) {
124                 req->num_retries--;
125                 req->te = event_add_timed(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 *);
132                 }
133                 EVENT_FD_WRITEABLE(req->nbtsock->fde);
134                 return;
135         }
136
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;
141         } else {
142                 req->state = NBT_REQUEST_DONE;
143                 req->status = NT_STATUS_OK;
144         }
145         if (req->async.fn) {
146                 req->async.fn(req);
147         } else if (req->is_reply) {
148                 talloc_free(req);
149         }
150 }
151
152
153
154 /**
155   handle recv events on a nbt name socket
156 */
157 static void nbt_name_socket_recv(struct nbt_name_socket *nbtsock)
158 {
159         TALLOC_CTX *tmp_ctx = talloc_new(nbtsock);
160         NTSTATUS status;
161         enum ndr_err_code ndr_err;
162         struct socket_address *src;
163         DATA_BLOB blob;
164         size_t nread, dsize;
165         struct nbt_name_packet *packet;
166         struct nbt_name_request *req;
167
168         status = socket_pending(nbtsock->sock, &dsize);
169         if (!NT_STATUS_IS_OK(status)) {
170                 talloc_free(tmp_ctx);
171                 return;
172         }
173
174         blob = data_blob_talloc(tmp_ctx, NULL, dsize);
175         if (blob.data == NULL) {
176                 talloc_free(tmp_ctx);
177                 return;
178         }
179
180         status = socket_recvfrom(nbtsock->sock, blob.data, blob.length, &nread,
181                                  tmp_ctx, &src);
182         if (!NT_STATUS_IS_OK(status)) {
183                 talloc_free(tmp_ctx);
184                 return;
185         }
186
187         packet = talloc(tmp_ctx, struct nbt_name_packet);
188         if (packet == NULL) {
189                 talloc_free(tmp_ctx);
190                 return;
191         }
192
193         /* parse the request */
194         ndr_err = ndr_pull_struct_blob(&blob, packet, nbtsock->iconv_convenience, 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",
199                          nt_errstr(status)));
200                 talloc_free(tmp_ctx);
201                 return;
202         }
203
204         if (DEBUGLVL(10)) {
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);
208         }
209
210         /* if its not a reply then pass it off to the incoming request
211            handler, if any */
212         if (!(packet->operation & NBT_FLAG_REPLY)) {
213                 if (nbtsock->incoming.handler) {
214                         nbtsock->incoming.handler(nbtsock, packet, src);
215                 }
216                 talloc_free(tmp_ctx);
217                 return;
218         }
219
220         /* find the matching request */
221         req = (struct nbt_name_request *)idr_find(nbtsock->idr,
222                                                   packet->name_trn_id);
223         if (req == NULL) {
224                 if (nbtsock->unexpected.handler) {
225                         nbtsock->unexpected.handler(nbtsock, packet, src);
226                 } else {
227                         DEBUG(10,("Failed to match request for incoming name packet id 0x%04x on %p\n",
228                                  packet->name_trn_id, nbtsock));
229                 }
230                 talloc_free(tmp_ctx);
231                 return;
232         }
233
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);
238 }
239
240 void nbt_name_socket_handle_response_packet(struct nbt_name_request *req,
241                                             struct nbt_name_packet *packet,
242                                             struct socket_address *src)
243 {
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) {
247                 uint32_t ttl;
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;
252                         goto done;
253                 }
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;
259                 /*
260                  * there is a timeout in the packet,
261                  * it is 5 + 4 * num_old_addresses
262                  *
263                  * although w2k3 screws it up
264                  * and uses num_old_addresses = 0
265                  *
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).
270                  */
271                 ttl = packet->answers[0].ttl;
272                 if ((ttl < (5 + 4*1)) || (ttl > (5 + 4*25))) {
273                         ttl = 5 + 4*25;
274                 }
275                 req->timeout = ttl;
276                 req->te = event_add_timed(req->nbtsock->event_ctx, req,
277                                           timeval_current_ofs(req->timeout, 0),
278                                           nbt_name_socket_timeout, req);
279                 return;
280         }
281
282
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;
288                 goto done;
289         }
290
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;
295         req->num_replies++;
296
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) {
300                 return;
301         }
302
303         nbt_name_request_destructor(req);
304         req->state  = NBT_REQUEST_DONE;
305         req->status = NT_STATUS_OK;
306
307 done:
308         if (req->async.fn) {
309                 req->async.fn(req);
310         }
311 }
312
313 /*
314   handle fd events on a nbt_name_socket
315 */
316 static void nbt_name_socket_handler(struct tevent_context *ev, struct tevent_fd *fde,
317                                     uint16_t flags, void *private)
318 {
319         struct nbt_name_socket *nbtsock = talloc_get_type(private,
320                                                           struct nbt_name_socket);
321         if (flags & EVENT_FD_WRITE) {
322                 nbt_name_socket_send(nbtsock);
323         }
324         if (flags & EVENT_FD_READ) {
325                 nbt_name_socket_recv(nbtsock);
326         }
327 }
328
329
330 /*
331   initialise a nbt_name_socket. The event_ctx is optional, if provided
332   then operations will use that event context
333 */
334 _PUBLIC_ struct nbt_name_socket *nbt_name_socket_init(TALLOC_CTX *mem_ctx,
335                                              struct tevent_context *event_ctx,
336                                              struct smb_iconv_convenience *iconv_convenience)
337 {
338         struct nbt_name_socket *nbtsock;
339         NTSTATUS status;
340
341         nbtsock = talloc(mem_ctx, struct nbt_name_socket);
342         if (nbtsock == NULL) goto failed;
343
344         nbtsock->event_ctx = talloc_reference(nbtsock, event_ctx);
345         if (nbtsock->event_ctx == NULL) goto failed;
346
347         status = socket_create("ip", SOCKET_TYPE_DGRAM, &nbtsock->sock, 0);
348         if (!NT_STATUS_IS_OK(status)) goto failed;
349
350         socket_set_option(nbtsock->sock, "SO_BROADCAST", "1");
351
352         talloc_steal(nbtsock, nbtsock->sock);
353
354         nbtsock->idr = idr_init(nbtsock);
355         if (nbtsock->idr == NULL) goto failed;
356
357         nbtsock->send_queue = NULL;
358         nbtsock->num_pending = 0;
359         nbtsock->incoming.handler = NULL;
360         nbtsock->unexpected.handler = NULL;
361         nbtsock->iconv_convenience = iconv_convenience;
362
363         nbtsock->fde = event_add_fd(nbtsock->event_ctx, nbtsock,
364                                     socket_get_fd(nbtsock->sock), 0,
365                                     nbt_name_socket_handler, nbtsock);
366
367         return nbtsock;
368
369 failed:
370         talloc_free(nbtsock);
371         return NULL;
372 }
373
374 /*
375   send off a nbt name request
376 */
377 struct nbt_name_request *nbt_name_request_send(struct nbt_name_socket *nbtsock,
378                                                struct socket_address *dest,
379                                                struct nbt_name_packet *request,
380                                                int timeout, int retries,
381                                                bool allow_multiple_replies)
382 {
383         struct nbt_name_request *req;
384         int id;
385         enum ndr_err_code ndr_err;
386
387         req = talloc_zero(nbtsock, struct nbt_name_request);
388         if (req == NULL) goto failed;
389
390         req->nbtsock                = nbtsock;
391         req->allow_multiple_replies = allow_multiple_replies;
392         req->state                  = NBT_REQUEST_SEND;
393         req->is_reply               = false;
394         req->timeout                = timeout;
395         req->num_retries            = retries;
396         req->dest                   = dest;
397         if (talloc_reference(req, dest) == NULL) goto failed;
398
399         /* we select a random transaction id unless the user supplied one */
400         if (request->name_trn_id == 0) {
401                 id = idr_get_new_random(req->nbtsock->idr, req, UINT16_MAX);
402         } else {
403                 if (idr_find(req->nbtsock->idr, request->name_trn_id)) goto failed;
404                 id = idr_get_new_above(req->nbtsock->idr, req, request->name_trn_id,
405                                        UINT16_MAX);
406         }
407         if (id == -1) goto failed;
408
409         request->name_trn_id = id;
410         req->name_trn_id     = id;
411
412         req->te = event_add_timed(nbtsock->event_ctx, req,
413                                   timeval_current_ofs(req->timeout, 0),
414                                   nbt_name_socket_timeout, req);
415
416         talloc_set_destructor(req, nbt_name_request_destructor);
417
418         ndr_err = ndr_push_struct_blob(&req->encoded, req,
419                                        req->nbtsock->iconv_convenience,
420                                        request,
421                                        (ndr_push_flags_fn_t)ndr_push_nbt_name_packet);
422         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) goto failed;
423
424         DLIST_ADD_END(nbtsock->send_queue, req, struct nbt_name_request *);
425
426         if (DEBUGLVL(10)) {
427                 DEBUG(10,("Queueing nbt packet to %s:%d\n",
428                           req->dest->addr, req->dest->port));
429                 NDR_PRINT_DEBUG(nbt_name_packet, request);
430         }
431
432         EVENT_FD_WRITEABLE(nbtsock->fde);
433
434         return req;
435
436 failed:
437         talloc_free(req);
438         return NULL;
439 }
440
441
442 /*
443   send off a nbt name reply
444 */
445 _PUBLIC_ NTSTATUS nbt_name_reply_send(struct nbt_name_socket *nbtsock,
446                              struct socket_address *dest,
447                              struct nbt_name_packet *request)
448 {
449         struct nbt_name_request *req;
450         enum ndr_err_code ndr_err;
451
452         req = talloc_zero(nbtsock, struct nbt_name_request);
453         NT_STATUS_HAVE_NO_MEMORY(req);
454
455         req->nbtsock   = nbtsock;
456         req->dest = dest;
457         if (talloc_reference(req, dest) == NULL) goto failed;
458         req->state     = NBT_REQUEST_SEND;
459         req->is_reply = true;
460
461         talloc_set_destructor(req, nbt_name_request_destructor);
462
463         if (DEBUGLVL(10)) {
464                 NDR_PRINT_DEBUG(nbt_name_packet, request);
465         }
466
467         ndr_err = ndr_push_struct_blob(&req->encoded, req,
468                                        req->nbtsock->iconv_convenience,
469                                        request,
470                                        (ndr_push_flags_fn_t)ndr_push_nbt_name_packet);
471         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
472                 talloc_free(req);
473                 return ndr_map_error2ntstatus(ndr_err);
474         }
475
476         DLIST_ADD_END(nbtsock->send_queue, req, struct nbt_name_request *);
477
478         EVENT_FD_WRITEABLE(nbtsock->fde);
479
480         return NT_STATUS_OK;
481
482 failed:
483         talloc_free(req);
484         return NT_STATUS_NO_MEMORY;
485 }
486
487 /*
488   wait for a nbt request to complete
489 */
490 NTSTATUS nbt_name_request_recv(struct nbt_name_request *req)
491 {
492         if (!req) return NT_STATUS_NO_MEMORY;
493
494         while (req->state < NBT_REQUEST_DONE) {
495                 if (event_loop_once(req->nbtsock->event_ctx) != 0) {
496                         req->state = NBT_REQUEST_ERROR;
497                         req->status = NT_STATUS_UNEXPECTED_NETWORK_ERROR;
498                         break;
499                 }
500         }
501         return req->status;
502 }
503
504
505 /*
506   setup a handler for incoming requests
507 */
508 _PUBLIC_ NTSTATUS nbt_set_incoming_handler(struct nbt_name_socket *nbtsock,
509                                   void (*handler)(struct nbt_name_socket *, struct nbt_name_packet *,
510                                                   struct socket_address *),
511                                   void *private)
512 {
513         nbtsock->incoming.handler = handler;
514         nbtsock->incoming.private_data = private;
515         EVENT_FD_READABLE(nbtsock->fde);
516         return NT_STATUS_OK;
517 }
518
519 /*
520   setup a handler for unexpected requests
521 */
522 NTSTATUS nbt_set_unexpected_handler(struct nbt_name_socket *nbtsock,
523                                     void (*handler)(struct nbt_name_socket *, struct nbt_name_packet *,
524                                                     struct socket_address *),
525                                     void *private_data)
526 {
527         nbtsock->unexpected.handler = handler;
528         nbtsock->unexpected.private_data = private_data;
529         EVENT_FD_READABLE(nbtsock->fde);
530         return NT_STATUS_OK;
531 }
532
533 /*
534   turn a NBT rcode into a NTSTATUS
535 */
536 _PUBLIC_ NTSTATUS nbt_rcode_to_ntstatus(uint8_t rcode)
537 {
538         int i;
539         struct {
540                 enum nbt_rcode rcode;
541                 NTSTATUS status;
542         } map[] = {
543                 { NBT_RCODE_FMT, NT_STATUS_INVALID_PARAMETER },
544                 { NBT_RCODE_SVR, NT_STATUS_SERVER_DISABLED },
545                 { NBT_RCODE_NAM, NT_STATUS_OBJECT_NAME_NOT_FOUND },
546                 { NBT_RCODE_IMP, NT_STATUS_NOT_SUPPORTED },
547                 { NBT_RCODE_RFS, NT_STATUS_ACCESS_DENIED },
548                 { NBT_RCODE_ACT, NT_STATUS_ADDRESS_ALREADY_EXISTS },
549                 { NBT_RCODE_CFT, NT_STATUS_CONFLICTING_ADDRESSES }
550         };
551         for (i=0;i<ARRAY_SIZE(map);i++) {
552                 if (map[i].rcode == rcode) {
553                         return map[i].status;
554                 }
555         }
556         return NT_STATUS_UNSUCCESSFUL;
557 }