Describe implication of upstream ICU-22610
[samba.git] / source3 / smbd / smb2_read.c
blob6c595a7c3406449b225131eb599efa27ee47e624
1 /*
2 Unix SMB/CIFS implementation.
3 Core SMB2 server
5 Copyright (C) Stefan Metzmacher 2009
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>.
21 #include "includes.h"
22 #include "system/filesys.h"
23 #include "smbd/smbd.h"
24 #include "smbd/globals.h"
25 #include "../libcli/smb/smb_common.h"
26 #include "libcli/security/security.h"
27 #include "../lib/util/tevent_ntstatus.h"
28 #include "rpc_server/srv_pipe_hnd.h"
29 #include "lib/util/sys_rw_data.h"
31 #undef DBGC_CLASS
32 #define DBGC_CLASS DBGC_SMB2
34 static struct tevent_req *smbd_smb2_read_send(TALLOC_CTX *mem_ctx,
35 struct tevent_context *ev,
36 struct smbd_smb2_request *smb2req,
37 struct files_struct *in_fsp,
38 uint8_t in_flags,
39 uint32_t in_length,
40 uint64_t in_offset,
41 uint32_t in_minimum,
42 uint32_t in_remaining);
43 static NTSTATUS smbd_smb2_read_recv(struct tevent_req *req,
44 TALLOC_CTX *mem_ctx,
45 DATA_BLOB *out_data,
46 uint32_t *out_remaining);
48 static void smbd_smb2_request_read_done(struct tevent_req *subreq);
49 NTSTATUS smbd_smb2_request_process_read(struct smbd_smb2_request *req)
51 struct smbXsrv_connection *xconn = req->xconn;
52 NTSTATUS status;
53 const uint8_t *inbody;
54 uint8_t in_flags;
55 uint32_t in_length;
56 uint64_t in_offset;
57 uint64_t in_file_id_persistent;
58 uint64_t in_file_id_volatile;
59 struct files_struct *in_fsp;
60 uint32_t in_minimum_count;
61 uint32_t in_remaining_bytes;
62 struct tevent_req *subreq;
64 status = smbd_smb2_request_verify_sizes(req, 0x31);
65 if (!NT_STATUS_IS_OK(status)) {
66 return smbd_smb2_request_error(req, status);
68 inbody = SMBD_SMB2_IN_BODY_PTR(req);
70 if (xconn->protocol >= PROTOCOL_SMB3_02) {
71 in_flags = CVAL(inbody, 0x03);
72 } else {
73 in_flags = 0;
75 in_length = IVAL(inbody, 0x04);
76 in_offset = BVAL(inbody, 0x08);
77 in_file_id_persistent = BVAL(inbody, 0x10);
78 in_file_id_volatile = BVAL(inbody, 0x18);
79 in_minimum_count = IVAL(inbody, 0x20);
80 in_remaining_bytes = IVAL(inbody, 0x28);
82 /* check the max read size */
83 if (in_length > xconn->smb2.server.max_read) {
84 DEBUG(2,("smbd_smb2_request_process_read: "
85 "client ignored max read: %s: 0x%08X: 0x%08X\n",
86 __location__, in_length, xconn->smb2.server.max_read));
87 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
90 status = smbd_smb2_request_verify_creditcharge(req, in_length);
91 if (!NT_STATUS_IS_OK(status)) {
92 return smbd_smb2_request_error(req, status);
95 in_fsp = file_fsp_smb2(req, in_file_id_persistent, in_file_id_volatile);
96 if (in_fsp == NULL) {
97 return smbd_smb2_request_error(req, NT_STATUS_FILE_CLOSED);
100 subreq = smbd_smb2_read_send(req, req->sconn->ev_ctx,
101 req, in_fsp,
102 in_flags,
103 in_length,
104 in_offset,
105 in_minimum_count,
106 in_remaining_bytes);
107 if (subreq == NULL) {
108 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
110 tevent_req_set_callback(subreq, smbd_smb2_request_read_done, req);
112 return smbd_smb2_request_pending_queue(req, subreq, 500);
115 static void smbd_smb2_request_read_done(struct tevent_req *subreq)
117 struct smbd_smb2_request *req = tevent_req_callback_data(subreq,
118 struct smbd_smb2_request);
119 uint16_t body_size;
120 uint8_t body_padding = req->xconn->smb2.smbtorture.read_body_padding;
121 DATA_BLOB outbody;
122 DATA_BLOB outdyn;
123 uint8_t out_data_offset;
124 DATA_BLOB out_data_buffer = data_blob_null;
125 uint32_t out_data_remaining = 0;
126 NTSTATUS status;
127 NTSTATUS error; /* transport error */
129 status = smbd_smb2_read_recv(subreq,
130 req,
131 &out_data_buffer,
132 &out_data_remaining);
133 TALLOC_FREE(subreq);
134 if (!NT_STATUS_IS_OK(status)) {
135 error = smbd_smb2_request_error(req, status);
136 if (!NT_STATUS_IS_OK(error)) {
137 smbd_server_connection_terminate(req->xconn,
138 nt_errstr(error));
139 return;
141 return;
145 * Only FSCTL_SMBTORTURE_GLOBAL_READ_RESPONSE_BODY_PADDING8
146 * sets body_padding to a value different from 0.
148 body_size = 0x10 + body_padding;
149 out_data_offset = SMB2_HDR_BODY + body_size;
151 outbody = smbd_smb2_generate_outbody(req, body_size);
152 if (outbody.data == NULL) {
153 error = smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
154 if (!NT_STATUS_IS_OK(error)) {
155 smbd_server_connection_terminate(req->xconn,
156 nt_errstr(error));
157 return;
159 return;
162 SSVAL(outbody.data, 0x00, 0x10 + 1); /* struct size */
163 SCVAL(outbody.data, 0x02,
164 out_data_offset); /* data offset */
165 SCVAL(outbody.data, 0x03, 0); /* reserved */
166 SIVAL(outbody.data, 0x04,
167 out_data_buffer.length); /* data length */
168 SIVAL(outbody.data, 0x08,
169 out_data_remaining); /* data remaining */
170 SIVAL(outbody.data, 0x0C, 0); /* reserved */
171 if (body_padding != 0) {
172 memset(outbody.data + 0x10, 0, body_padding);
175 outdyn = out_data_buffer;
177 error = smbd_smb2_request_done(req, outbody, &outdyn);
178 if (!NT_STATUS_IS_OK(error)) {
179 smbd_server_connection_terminate(req->xconn,
180 nt_errstr(error));
181 return;
185 struct smbd_smb2_read_state {
186 struct smbd_smb2_request *smb2req;
187 struct smb_request *smbreq;
188 files_struct *fsp;
189 uint8_t in_flags;
190 uint32_t in_length;
191 uint64_t in_offset;
192 uint32_t in_minimum;
193 DATA_BLOB out_headers;
194 uint8_t _out_hdr_buf[NBT_HDR_SIZE + SMB2_HDR_BODY + 0x10];
195 DATA_BLOB out_data;
196 uint32_t out_remaining;
199 static int smb2_smb2_read_state_deny_destructor(struct smbd_smb2_read_state *state)
201 return -1;
204 /* struct smbd_smb2_read_state destructor. Send the SMB2_READ data. */
205 static int smb2_sendfile_send_data(struct smbd_smb2_read_state *state)
207 uint32_t in_length = state->in_length;
208 uint64_t in_offset = state->in_offset;
209 files_struct *fsp = state->fsp;
210 const DATA_BLOB *hdr = state->smb2req->queue_entry.sendfile_header;
211 NTSTATUS *pstatus = state->smb2req->queue_entry.sendfile_status;
212 struct smbXsrv_connection *xconn = state->smb2req->xconn;
213 ssize_t nread;
214 ssize_t ret;
215 int saved_errno;
217 nread = SMB_VFS_SENDFILE(xconn->transport.sock,
218 fsp,
219 hdr,
220 in_offset,
221 in_length);
222 DBG_DEBUG("SMB_VFS_SENDFILE returned %zd on file %s\n",
223 nread,
224 fsp_str_dbg(fsp));
226 if (nread == -1) {
227 saved_errno = errno;
230 * Returning ENOSYS means no data at all was sent.
231 Do this as a normal read. */
232 if (errno == ENOSYS) {
233 goto normal_read;
236 if (errno == ENOTSUP) {
237 set_use_sendfile(SNUM(fsp->conn), false);
238 DBG_WARNING("Disabling sendfile use as sendfile is "
239 "not supported by the system\n");
240 goto normal_read;
243 if (errno == EINTR) {
245 * Special hack for broken Linux with no working sendfile. If we
246 * return EINTR we sent the header but not the rest of the data.
247 * Fake this up by doing read/write calls.
249 set_use_sendfile(SNUM(fsp->conn), false);
250 nread = fake_sendfile(xconn, fsp, in_offset, in_length);
251 if (nread == -1) {
252 saved_errno = errno;
253 DBG_ERR("fake_sendfile failed for file %s "
254 "(%s) for client %s. Terminating\n",
255 fsp_str_dbg(fsp),
256 strerror(saved_errno),
257 smbXsrv_connection_dbg(xconn));
258 *pstatus = map_nt_error_from_unix_common(saved_errno);
259 return 0;
261 goto out;
264 DBG_ERR("sendfile failed for file "
265 "%s (%s) for client %s. Terminating\n",
266 fsp_str_dbg(fsp),
267 strerror(saved_errno),
268 smbXsrv_connection_dbg(xconn));
269 *pstatus = map_nt_error_from_unix_common(saved_errno);
270 return 0;
271 } else if (nread == 0) {
273 * Some sendfile implementations return 0 to indicate
274 * that there was a short read, but nothing was
275 * actually written to the socket. In this case,
276 * fallback to the normal read path so the header gets
277 * the correct byte count.
279 DBG_NOTICE("sendfile sent zero bytes "
280 "falling back to the normal read: %s\n",
281 fsp_str_dbg(fsp));
282 goto normal_read;
286 * We got a short read
288 goto out;
290 normal_read:
291 /* Send out the header. */
292 ret = write_data(xconn->transport.sock,
293 (const char *)hdr->data, hdr->length);
294 if (ret != hdr->length) {
295 saved_errno = errno;
296 DBG_ERR("write_data failed for file "
297 "%s (%s) for client %s. Terminating\n",
298 fsp_str_dbg(fsp),
299 strerror(saved_errno),
300 smbXsrv_connection_dbg(xconn));
301 *pstatus = map_nt_error_from_unix_common(saved_errno);
302 return 0;
304 nread = fake_sendfile(xconn, fsp, in_offset, in_length);
305 if (nread == -1) {
306 saved_errno = errno;
307 DBG_ERR("fake_sendfile failed for file %s (%s) for client %s. "
308 "Terminating\n",
309 fsp_str_dbg(fsp),
310 strerror(saved_errno),
311 smbXsrv_connection_dbg(xconn));
312 *pstatus = map_nt_error_from_unix_common(saved_errno);
313 return 0;
316 out:
318 if (nread < in_length) {
319 ret = sendfile_short_send(xconn, fsp, nread,
320 hdr->length, in_length);
321 if (ret == -1) {
322 saved_errno = errno;
323 DBG_ERR("sendfile_short_send "
324 "failed for file %s (%s) for client %s. "
325 "Terminating\n",
326 fsp_str_dbg(fsp),
327 strerror(saved_errno),
328 smbXsrv_connection_dbg(xconn));
329 *pstatus = map_nt_error_from_unix_common(saved_errno);
330 return 0;
334 *pstatus = NT_STATUS_OK;
335 return 0;
338 static NTSTATUS schedule_smb2_sendfile_read(struct smbd_smb2_request *smb2req,
339 struct smbd_smb2_read_state *state)
341 files_struct *fsp = state->fsp;
344 * We cannot use sendfile if...
345 * We were not configured to do so OR
346 * Signing is active OR
347 * This is a compound SMB2 operation OR
348 * fsp is a STREAM file OR
349 * It's not a regular file OR
350 * Requested offset is greater than file size OR
351 * there's not enough data in the file.
352 * Phew :-). Luckily this means most
353 * reads on most normal files. JRA.
356 if (!lp__use_sendfile(SNUM(fsp->conn)) ||
357 smb2req->do_signing ||
358 smb2req->do_encryption ||
359 smbd_smb2_is_compound(smb2req) ||
360 fsp_is_alternate_stream(fsp) ||
361 (!S_ISREG(fsp->fsp_name->st.st_ex_mode)) ||
362 (state->in_offset >= fsp->fsp_name->st.st_ex_size) ||
363 (fsp->fsp_name->st.st_ex_size < state->in_offset + state->in_length))
365 return NT_STATUS_RETRY;
368 /* We've already checked there's this amount of data
369 to read. */
370 state->out_data.length = state->in_length;
371 state->out_remaining = 0;
373 state->out_headers = data_blob_const(state->_out_hdr_buf,
374 sizeof(state->_out_hdr_buf));
375 return NT_STATUS_OK;
378 static void smbd_smb2_read_pipe_done(struct tevent_req *subreq);
380 /*******************************************************************
381 Common read complete processing function for both synchronous and
382 asynchronous reads.
383 *******************************************************************/
385 NTSTATUS smb2_read_complete(struct tevent_req *req, ssize_t nread, int err)
387 struct smbd_smb2_read_state *state = tevent_req_data(req,
388 struct smbd_smb2_read_state);
389 files_struct *fsp = state->fsp;
391 if (nread < 0) {
392 NTSTATUS status = map_nt_error_from_unix(err);
394 DEBUG( 3,( "smb2_read_complete: file %s nread = %d. "
395 "Error = %s (NTSTATUS %s)\n",
396 fsp_str_dbg(fsp),
397 (int)nread,
398 strerror(err),
399 nt_errstr(status)));
401 return status;
403 if (nread == 0 && state->in_length != 0) {
404 DEBUG(5,("smb2_read_complete: read_file[%s] end of file\n",
405 fsp_str_dbg(fsp)));
406 return NT_STATUS_END_OF_FILE;
409 if (nread < state->in_minimum) {
410 DEBUG(5,("smb2_read_complete: read_file[%s] read less %d than "
411 "minimum requested %u. Returning end of file\n",
412 fsp_str_dbg(fsp),
413 (int)nread,
414 (unsigned int)state->in_minimum));
415 return NT_STATUS_END_OF_FILE;
418 DEBUG(3,("smbd_smb2_read: %s, file %s, length=%lu offset=%lu read=%lu\n",
419 fsp_fnum_dbg(fsp),
420 fsp_str_dbg(fsp),
421 (unsigned long)state->in_length,
422 (unsigned long)state->in_offset,
423 (unsigned long)nread));
425 state->out_data.length = nread;
426 state->out_remaining = 0;
428 return NT_STATUS_OK;
431 static bool smbd_smb2_read_cancel(struct tevent_req *req)
433 struct smbd_smb2_read_state *state =
434 tevent_req_data(req,
435 struct smbd_smb2_read_state);
437 return cancel_smb2_aio(state->smbreq);
440 static struct tevent_req *smbd_smb2_read_send(TALLOC_CTX *mem_ctx,
441 struct tevent_context *ev,
442 struct smbd_smb2_request *smb2req,
443 struct files_struct *fsp,
444 uint8_t in_flags,
445 uint32_t in_length,
446 uint64_t in_offset,
447 uint32_t in_minimum,
448 uint32_t in_remaining)
450 NTSTATUS status;
451 struct tevent_req *req = NULL;
452 struct smbd_smb2_read_state *state = NULL;
453 struct smb_request *smbreq = NULL;
454 connection_struct *conn = smb2req->tcon->compat;
455 ssize_t nread = -1;
456 struct lock_struct lock;
457 int saved_errno;
459 req = tevent_req_create(mem_ctx, &state,
460 struct smbd_smb2_read_state);
461 if (req == NULL) {
462 return NULL;
464 state->smb2req = smb2req;
465 state->in_flags = in_flags;
466 state->in_length = in_length;
467 state->in_offset = in_offset;
468 state->in_minimum = in_minimum;
469 state->out_data = data_blob_null;
470 state->out_remaining = 0;
472 DEBUG(10,("smbd_smb2_read: %s - %s\n",
473 fsp_str_dbg(fsp), fsp_fnum_dbg(fsp)));
475 smbreq = smbd_smb2_fake_smb_request(smb2req, fsp);
476 if (tevent_req_nomem(smbreq, req)) {
477 return tevent_req_post(req, ev);
479 state->smbreq = smbreq;
481 if (fsp->fsp_flags.is_directory) {
482 tevent_req_nterror(req, NT_STATUS_INVALID_DEVICE_REQUEST);
483 return tevent_req_post(req, ev);
486 state->fsp = fsp;
488 if (IS_IPC(smbreq->conn)) {
489 struct tevent_req *subreq = NULL;
490 bool ok;
492 state->out_data = data_blob_talloc(state, NULL, in_length);
493 if (in_length > 0 && tevent_req_nomem(state->out_data.data, req)) {
494 return tevent_req_post(req, ev);
497 if (!fsp_is_np(fsp)) {
498 tevent_req_nterror(req, NT_STATUS_FILE_CLOSED);
499 return tevent_req_post(req, ev);
502 subreq = np_read_send(state, ev,
503 fsp->fake_file_handle,
504 state->out_data.data,
505 state->out_data.length);
506 if (tevent_req_nomem(subreq, req)) {
507 return tevent_req_post(req, ev);
509 tevent_req_set_callback(subreq,
510 smbd_smb2_read_pipe_done,
511 req);
514 * Make sure we mark the fsp as having outstanding async
515 * activity so we don't crash on shutdown close.
518 ok = aio_add_req_to_fsp(fsp, req);
519 if (!ok) {
520 tevent_req_nterror(req, NT_STATUS_NO_MEMORY);
521 return tevent_req_post(req, ev);
524 return req;
527 if (!CHECK_READ_SMB2(fsp)) {
528 tevent_req_nterror(req, NT_STATUS_ACCESS_DENIED);
529 return tevent_req_post(req, ev);
532 status = schedule_smb2_aio_read(fsp->conn,
533 smbreq,
534 fsp,
535 state,
536 &state->out_data,
537 (off_t)in_offset,
538 (size_t)in_length);
540 if (NT_STATUS_IS_OK(status)) {
542 * Doing an async read, allow this
543 * request to be canceled
545 tevent_req_set_cancel_fn(req, smbd_smb2_read_cancel);
546 return req;
549 if (!NT_STATUS_EQUAL(status, NT_STATUS_RETRY)) {
550 /* Real error in setting up aio. Fail. */
551 tevent_req_nterror(req, status);
552 return tevent_req_post(req, ev);
555 /* Fallback to synchronous. */
557 init_strict_lock_struct(fsp,
558 fsp->op->global->open_persistent_id,
559 in_offset,
560 in_length,
561 READ_LOCK,
562 lp_posix_cifsu_locktype(fsp),
563 &lock);
565 if (!SMB_VFS_STRICT_LOCK_CHECK(conn, fsp, &lock)) {
566 tevent_req_nterror(req, NT_STATUS_FILE_LOCK_CONFLICT);
567 return tevent_req_post(req, ev);
570 /* Try sendfile in preference. */
571 status = schedule_smb2_sendfile_read(smb2req, state);
572 if (NT_STATUS_IS_OK(status)) {
573 tevent_req_done(req);
574 return tevent_req_post(req, ev);
576 if (!NT_STATUS_EQUAL(status, NT_STATUS_RETRY)) {
577 tevent_req_nterror(req, status);
578 return tevent_req_post(req, ev);
581 /* Ok, read into memory. Allocate the out buffer. */
582 state->out_data = data_blob_talloc(state, NULL, in_length);
583 if (in_length > 0 && tevent_req_nomem(state->out_data.data, req)) {
584 return tevent_req_post(req, ev);
587 nread = read_file(fsp,
588 (char *)state->out_data.data,
589 in_offset,
590 in_length);
592 saved_errno = errno;
594 DEBUG(10,("smbd_smb2_read: file %s, %s, offset=%llu "
595 "len=%llu returned %lld\n",
596 fsp_str_dbg(fsp),
597 fsp_fnum_dbg(fsp),
598 (unsigned long long)in_offset,
599 (unsigned long long)in_length,
600 (long long)nread));
602 status = smb2_read_complete(req, nread, saved_errno);
603 if (!NT_STATUS_IS_OK(status)) {
604 tevent_req_nterror(req, status);
605 } else {
606 /* Success. */
607 tevent_req_done(req);
609 return tevent_req_post(req, ev);
612 static void smbd_smb2_read_pipe_done(struct tevent_req *subreq)
614 struct tevent_req *req = tevent_req_callback_data(subreq,
615 struct tevent_req);
616 struct smbd_smb2_read_state *state = tevent_req_data(req,
617 struct smbd_smb2_read_state);
618 NTSTATUS status;
619 ssize_t nread = -1;
620 bool is_data_outstanding;
622 status = np_read_recv(subreq, &nread, &is_data_outstanding);
623 TALLOC_FREE(subreq);
624 if (!NT_STATUS_IS_OK(status)) {
625 NTSTATUS old = status;
626 status = nt_status_np_pipe(old);
627 tevent_req_nterror(req, status);
628 return;
631 if (nread == 0 && state->out_data.length != 0) {
632 tevent_req_nterror(req, NT_STATUS_END_OF_FILE);
633 return;
636 state->out_data.length = nread;
637 state->out_remaining = 0;
640 * TODO: add STATUS_BUFFER_OVERFLOW handling, once we also
641 * handle it in SMB1 pipe_read_andx_done().
644 tevent_req_done(req);
647 static NTSTATUS smbd_smb2_read_recv(struct tevent_req *req,
648 TALLOC_CTX *mem_ctx,
649 DATA_BLOB *out_data,
650 uint32_t *out_remaining)
652 NTSTATUS status;
653 struct smbd_smb2_read_state *state = tevent_req_data(req,
654 struct smbd_smb2_read_state);
656 if (tevent_req_is_nterror(req, &status)) {
657 tevent_req_received(req);
658 return status;
661 *out_data = state->out_data;
662 talloc_steal(mem_ctx, out_data->data);
663 *out_remaining = state->out_remaining;
665 if (state->out_headers.length > 0) {
666 talloc_steal(mem_ctx, state);
667 talloc_set_destructor(state, smb2_smb2_read_state_deny_destructor);
668 tevent_req_received(req);
669 state->smb2req->queue_entry.sendfile_header = &state->out_headers;
670 state->smb2req->queue_entry.sendfile_body_size = state->in_length;
671 talloc_set_destructor(state, smb2_sendfile_send_data);
672 } else {
673 tevent_req_received(req);
676 return NT_STATUS_OK;