source: branches/samba-3.3.x/source/libsmb/async_smb.c

Last change on this file was 342, checked in by Herwig Bauernfeind, 16 years ago

Update 3.3 to 3.3.9
File size: 11.7 KB
Line 
1/*
2 Unix SMB/CIFS implementation.
3 Infrastructure for async SMB client requests
4 Copyright (C) Volker Lendecke 2008
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
18*/
19
20#include "includes.h"
21
22/*
23 * Fetch an error out of a NBT packet
24 */
25
26NTSTATUS cli_pull_error(char *buf)
27{
28 uint32_t flags2 = SVAL(buf, smb_flg2);
29
30 if (flags2 & FLAGS2_32_BIT_ERROR_CODES) {
31 return NT_STATUS(IVAL(buf, smb_rcls));
32 }
33
34 /* if the client uses dos errors, but there is no error,
35 we should return no error here, otherwise it looks
36 like an unknown bad NT_STATUS. jmcd */
37 if (CVAL(buf, smb_rcls) == 0)
38 return NT_STATUS_OK;
39
40 return NT_STATUS_DOS(CVAL(buf, smb_rcls), SVAL(buf,smb_err));
41}
42
43/*
44 * Compatibility helper for the sync APIs: Fake NTSTATUS in cli->inbuf
45 */
46
47void cli_set_error(struct cli_state *cli, NTSTATUS status)
48{
49 uint32_t flags2 = SVAL(cli->inbuf, smb_flg2);
50
51 if (NT_STATUS_IS_DOS(status)) {
52 SSVAL(cli->inbuf, smb_flg2,
53 flags2 & ~FLAGS2_32_BIT_ERROR_CODES);
54 SCVAL(cli->inbuf, smb_rcls, NT_STATUS_DOS_CLASS(status));
55 SSVAL(cli->inbuf, smb_err, NT_STATUS_DOS_CODE(status));
56 return;
57 }
58
59 SSVAL(cli->inbuf, smb_flg2, flags2 | FLAGS2_32_BIT_ERROR_CODES);
60 SIVAL(cli->inbuf, smb_rcls, NT_STATUS_V(status));
61 return;
62}
63
64/*
65 * Allocate a new mid
66 */
67
68static uint16_t cli_new_mid(struct cli_state *cli)
69{
70 uint16_t result;
71 struct cli_request *req;
72
73 while (true) {
74 result = cli->mid++;
75 if (result == 0) {
76 continue;
77 }
78
79 for (req = cli->outstanding_requests; req; req = req->next) {
80 if (result == req->mid) {
81 break;
82 }
83 }
84
85 if (req == NULL) {
86 return result;
87 }
88 }
89}
90
91static char *cli_request_print(TALLOC_CTX *mem_ctx, struct async_req *req)
92{
93 char *result = async_req_print(mem_ctx, req);
94 struct cli_request *cli_req = cli_request_get(req);
95
96 if (result == NULL) {
97 return NULL;
98 }
99
100 return talloc_asprintf_append_buffer(
101 result, "mid=%d\n", cli_req->mid);
102}
103
104static int cli_request_destructor(struct cli_request *req)
105{
106 if (req->enc_state != NULL) {
107 common_free_enc_buffer(req->enc_state, req->outbuf);
108 }
109 DLIST_REMOVE(req->cli->outstanding_requests, req);
110 return 0;
111}
112
113/*
114 * Create a fresh async smb request
115 */
116
117struct async_req *cli_request_new(TALLOC_CTX *mem_ctx,
118 struct event_context *ev,
119 struct cli_state *cli,
120 uint8_t num_words, size_t num_bytes,
121 struct cli_request **preq)
122{
123 struct async_req *result;
124 struct cli_request *cli_req;
125 size_t bufsize = smb_size + num_words * 2 + num_bytes;
126
127 result = async_req_new(mem_ctx, ev);
128 if (result == NULL) {
129 return NULL;
130 }
131
132 cli_req = (struct cli_request *)talloc_size(
133 result, sizeof(*cli_req) + bufsize);
134 if (cli_req == NULL) {
135 TALLOC_FREE(result);
136 return NULL;
137 }
138 talloc_set_name_const(cli_req, "struct cli_request");
139 result->private_data = cli_req;
140 result->print = cli_request_print;
141
142 cli_req->async = result;
143 cli_req->cli = cli;
144 cli_req->outbuf = ((char *)cli_req + sizeof(*cli_req));
145 cli_req->sent = 0;
146 cli_req->mid = cli_new_mid(cli);
147 cli_req->inbuf = NULL;
148 cli_req->enc_state = NULL;
149
150 SCVAL(cli_req->outbuf, smb_wct, num_words);
151 SSVAL(cli_req->outbuf, smb_vwv + num_words * 2, num_bytes);
152
153 DLIST_ADD_END(cli->outstanding_requests, cli_req,
154 struct cli_request *);
155 talloc_set_destructor(cli_req, cli_request_destructor);
156
157 DEBUG(10, ("cli_request_new: mid=%d\n", cli_req->mid));
158
159 *preq = cli_req;
160 return result;
161}
162
163/*
164 * Convenience function to get the SMB part out of an async_req
165 */
166
167struct cli_request *cli_request_get(struct async_req *req)
168{
169 if (req == NULL) {
170 return NULL;
171 }
172 return talloc_get_type_abort(req->private_data, struct cli_request);
173}
174
175/*
176 * A PDU has arrived on cli->evt_inbuf
177 */
178
179static void handle_incoming_pdu(struct cli_state *cli)
180{
181 struct cli_request *req;
182 uint16_t mid;
183 size_t raw_pdu_len, buf_len, pdu_len, rest_len;
184 char *pdu;
185 NTSTATUS status;
186
187 /*
188 * The encrypted PDU len might differ from the unencrypted one
189 */
190 raw_pdu_len = smb_len(cli->evt_inbuf) + 4;
191 buf_len = talloc_get_size(cli->evt_inbuf);
192 rest_len = buf_len - raw_pdu_len;
193
194 if (buf_len == raw_pdu_len) {
195 /*
196 * Optimal case: Exactly one PDU was in the socket buffer
197 */
198 pdu = cli->evt_inbuf;
199 cli->evt_inbuf = NULL;
200 }
201 else {
202 DEBUG(11, ("buf_len = %d, raw_pdu_len = %d, splitting "
203 "buffer\n", (int)buf_len, (int)raw_pdu_len));
204
205 if (raw_pdu_len < rest_len) {
206 /*
207 * The PDU is shorter, talloc_memdup that one.
208 */
209 pdu = (char *)talloc_memdup(
210 cli, cli->evt_inbuf, raw_pdu_len);
211
212 memmove(cli->evt_inbuf, cli->evt_inbuf + raw_pdu_len,
213 buf_len - raw_pdu_len);
214
215 cli->evt_inbuf = TALLOC_REALLOC_ARRAY(
216 NULL, cli->evt_inbuf, char, rest_len);
217
218 if (pdu == NULL) {
219 status = NT_STATUS_NO_MEMORY;
220 goto invalidate_requests;
221 }
222 }
223 else {
224 /*
225 * The PDU is larger than the rest, talloc_memdup the
226 * rest
227 */
228 pdu = cli->evt_inbuf;
229
230 cli->evt_inbuf = (char *)talloc_memdup(
231 cli, pdu + raw_pdu_len, rest_len);
232
233 if (cli->evt_inbuf == NULL) {
234 status = NT_STATUS_NO_MEMORY;
235 goto invalidate_requests;
236 }
237 }
238
239 }
240
241 if ((raw_pdu_len == 4) && (CVAL(pdu, 0) == SMBkeepalive)) {
242 DEBUG(10, ("Got keepalive\n"));
243 TALLOC_FREE(pdu);
244 return;
245 }
246
247 /*
248 * TODO: Handle oplock break requests
249 */
250
251 if (cli_encryption_on(cli) && CVAL(pdu, 0) == 0) {
252 uint16_t enc_ctx_num;
253
254 status = get_enc_ctx_num((uint8_t *)pdu, &enc_ctx_num);
255 if (!NT_STATUS_IS_OK(status)) {
256 DEBUG(10, ("get_enc_ctx_num returned %s\n",
257 nt_errstr(status)));
258 goto invalidate_requests;
259 }
260
261 if (enc_ctx_num != cli->trans_enc_state->enc_ctx_num) {
262 DEBUG(10, ("wrong enc_ctx %d, expected %d\n",
263 enc_ctx_num,
264 cli->trans_enc_state->enc_ctx_num));
265 status = NT_STATUS_INVALID_HANDLE;
266 goto invalidate_requests;
267 }
268
269 status = common_decrypt_buffer(cli->trans_enc_state,
270 pdu);
271 if (!NT_STATUS_IS_OK(status)) {
272 DEBUG(10, ("common_decrypt_buffer returned %s\n",
273 nt_errstr(status)));
274 goto invalidate_requests;
275 }
276 }
277
278 if (!cli_check_sign_mac(cli, pdu)) {
279 DEBUG(10, ("cli_check_sign_mac failed\n"));
280 status = NT_STATUS_ACCESS_DENIED;
281 goto invalidate_requests;
282 }
283
284 mid = SVAL(pdu, smb_mid);
285
286 DEBUG(10, ("handle_incoming_pdu: got mid %d\n", mid));
287
288 for (req = cli->outstanding_requests; req; req = req->next) {
289 if (req->mid == mid) {
290 break;
291 }
292 }
293
294 pdu_len = smb_len(pdu) + 4;
295
296 if (req == NULL) {
297 DEBUG(3, ("Request for mid %d not found, dumping PDU\n", mid));
298
299 TALLOC_FREE(pdu);
300 return;
301 }
302
303 req->inbuf = talloc_move(req, &pdu);
304
305 async_req_done(req->async);
306 return;
307
308 invalidate_requests:
309
310 DEBUG(10, ("handle_incoming_pdu: Aborting with %s\n",
311 nt_errstr(status)));
312
313 for (req = cli->outstanding_requests; req; req = req->next) {
314 async_req_error(req->async, status);
315 }
316 return;
317}
318
319/*
320 * fd event callback. This is the basic connection to the socket
321 */
322
323static void cli_state_handler(struct event_context *event_ctx,
324 struct fd_event *event, uint16 flags, void *p)
325{
326 struct cli_state *cli = (struct cli_state *)p;
327 struct cli_request *req, *next;
328 NTSTATUS status;
329
330 DEBUG(11, ("cli_state_handler called with flags %d\n", flags));
331
332 if (flags & EVENT_FD_READ) {
333 int res, available;
334 size_t old_size, new_size;
335 char *tmp;
336
337 res = ioctl(cli->fd, FIONREAD, &available);
338 if (res == -1) {
339 DEBUG(10, ("ioctl(FIONREAD) failed: %s\n",
340 strerror(errno)));
341 status = map_nt_error_from_unix(errno);
342 goto sock_error;
343 }
344
345 if (available == 0) {
346 /* EOF */
347 status = NT_STATUS_END_OF_FILE;
348 goto sock_error;
349 }
350
351 old_size = talloc_get_size(cli->evt_inbuf);
352 new_size = old_size + available;
353
354 if (new_size < old_size) {
355 /* wrap */
356 status = NT_STATUS_UNEXPECTED_IO_ERROR;
357 goto sock_error;
358 }
359
360 tmp = TALLOC_REALLOC_ARRAY(cli, cli->evt_inbuf, char,
361 new_size);
362 if (tmp == NULL) {
363 /* nomem */
364 status = NT_STATUS_NO_MEMORY;
365 goto sock_error;
366 }
367 cli->evt_inbuf = tmp;
368
369 res = sys_recv(cli->fd, cli->evt_inbuf + old_size, available, 0);
370 if (res == -1) {
371 DEBUG(10, ("recv failed: %s\n", strerror(errno)));
372 status = map_nt_error_from_unix(errno);
373 goto sock_error;
374 }
375
376 DEBUG(11, ("cli_state_handler: received %d bytes, "
377 "smb_len(evt_inbuf) = %d\n", (int)res,
378 smb_len(cli->evt_inbuf)));
379
380 /* recv *might* have returned less than announced */
381 new_size = old_size + res;
382
383 /* shrink, so I don't expect errors here */
384 cli->evt_inbuf = TALLOC_REALLOC_ARRAY(cli, cli->evt_inbuf,
385 char, new_size);
386
387 while ((cli->evt_inbuf != NULL)
388 && ((smb_len(cli->evt_inbuf) + 4) <= new_size)) {
389 /*
390 * we've got a complete NBT level PDU in evt_inbuf
391 */
392 handle_incoming_pdu(cli);
393 new_size = talloc_get_size(cli->evt_inbuf);
394 }
395 }
396
397 if (flags & EVENT_FD_WRITE) {
398 size_t to_send;
399 ssize_t sent;
400
401 for (req = cli->outstanding_requests; req; req = req->next) {
402 to_send = smb_len(req->outbuf)+4;
403 if (to_send > req->sent) {
404 break;
405 }
406 }
407
408 if (req == NULL) {
409 event_fd_set_not_writeable(event);
410 return;
411 }
412
413 sent = sys_send(cli->fd, req->outbuf + req->sent,
414 to_send - req->sent, 0);
415
416 if (sent < 0) {
417 status = map_nt_error_from_unix(errno);
418 goto sock_error;
419 }
420
421 req->sent += sent;
422
423 if (req->sent == to_send) {
424 return;
425 }
426 }
427 return;
428
429 sock_error:
430 for (req = cli->outstanding_requests; req; req = next) {
431 next = req;
432 async_req_error(req->async, status);
433 }
434 TALLOC_FREE(cli->fd_event);
435 close(cli->fd);
436 cli->fd = -1;
437}
438
439/*
440 * Holder for a talloc_destructor, we need to zero out the pointers in cli
441 * when deleting
442 */
443struct cli_tmp_event {
444 struct cli_state *cli;
445};
446
447static int cli_tmp_event_destructor(struct cli_tmp_event *e)
448{
449 TALLOC_FREE(e->cli->fd_event);
450 TALLOC_FREE(e->cli->event_ctx);
451 return 0;
452}
453
454/*
455 * Create a temporary event context for use in the sync helper functions
456 */
457
458struct cli_tmp_event *cli_tmp_event_ctx(TALLOC_CTX *mem_ctx,
459 struct cli_state *cli)
460{
461 struct cli_tmp_event *state;
462
463 if (cli->event_ctx != NULL) {
464 return NULL;
465 }
466
467 state = talloc(mem_ctx, struct cli_tmp_event);
468 if (state == NULL) {
469 return NULL;
470 }
471 state->cli = cli;
472 talloc_set_destructor(state, cli_tmp_event_destructor);
473
474 cli->event_ctx = event_context_init(state);
475 if (cli->event_ctx == NULL) {
476 TALLOC_FREE(state);
477 return NULL;
478 }
479
480 cli->fd_event = event_add_fd(cli->event_ctx, state, cli->fd,
481 EVENT_FD_READ, cli_state_handler, cli);
482 if (cli->fd_event == NULL) {
483 TALLOC_FREE(state);
484 return NULL;
485 }
486 return state;
487}
488
489/*
490 * Attach an event context permanently to a cli_struct
491 */
492
493NTSTATUS cli_add_event_ctx(struct cli_state *cli,
494 struct event_context *event_ctx)
495{
496 cli->event_ctx = event_ctx;
497 cli->fd_event = event_add_fd(event_ctx, cli, cli->fd, EVENT_FD_READ,
498 cli_state_handler, cli);
499 if (cli->fd_event == NULL) {
500 return NT_STATUS_NO_MEMORY;
501 }
502 return NT_STATUS_OK;
503}
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