summaryrefslogtreecommitdiff
path: root/source4/libcli/smb2/transport.c
blob: 6d7531f4b5bd77b3bf14a8a5a61e7326a21caa58 (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
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
/* 
   Unix SMB/CIFS implementation.

   SMB2 client transport context management 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 3 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, see <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "libcli/raw/libcliraw.h"
#include "libcli/raw/raw_proto.h"
#include "libcli/smb2/smb2.h"
#include "libcli/smb2/smb2_calls.h"
#include "lib/socket/socket.h"
#include "lib/events/events.h"
#include "lib/stream/packet.h"
#include "../lib/util/dlinklist.h"


/*
  an event has happened on the socket
*/
static void smb2_transport_event_handler(struct event_context *ev, 
					 struct fd_event *fde, 
					 uint16_t flags, void *private)
{
	struct smb2_transport *transport = talloc_get_type(private,
							   struct smb2_transport);
	if (flags & EVENT_FD_READ) {
		packet_recv(transport->packet);
		return;
	}
	if (flags & EVENT_FD_WRITE) {
		packet_queue_run(transport->packet);
	}
}

/*
  destroy a transport
 */
static int transport_destructor(struct smb2_transport *transport)
{
	smb2_transport_dead(transport, NT_STATUS_LOCAL_DISCONNECT);
	return 0;
}


/*
  handle receive errors
*/
static void smb2_transport_error(void *private, NTSTATUS status)
{
	struct smb2_transport *transport = talloc_get_type(private, 
							   struct smb2_transport);
	smb2_transport_dead(transport, status);
}

static NTSTATUS smb2_transport_finish_recv(void *private, DATA_BLOB blob);

/*
  create a transport structure based on an established socket
*/
struct smb2_transport *smb2_transport_init(struct smbcli_socket *sock,
					   TALLOC_CTX *parent_ctx,
					   struct smbcli_options *options)
{
	struct smb2_transport *transport;

	transport = talloc_zero(parent_ctx, struct smb2_transport);
	if (!transport) return NULL;

	transport->socket = talloc_steal(transport, sock);
	transport->options = *options;

	/* setup the stream -> packet parser */
	transport->packet = packet_init(transport);
	if (transport->packet == NULL) {
		talloc_free(transport);
		return NULL;
	}
	packet_set_private(transport->packet, transport);
	packet_set_socket(transport->packet, transport->socket->sock);
	packet_set_callback(transport->packet, smb2_transport_finish_recv);
	packet_set_full_request(transport->packet, packet_full_request_nbt);
	packet_set_error_handler(transport->packet, smb2_transport_error);
	packet_set_event_context(transport->packet, transport->socket->event.ctx);
	packet_set_nofree(transport->packet);

	/* take over event handling from the socket layer - it only
	   handles events up until we are connected */
	talloc_free(transport->socket->event.fde);
	transport->socket->event.fde = event_add_fd(transport->socket->event.ctx,
						    transport->socket,
						    socket_get_fd(transport->socket->sock),
						    EVENT_FD_READ,
						    smb2_transport_event_handler,
						    transport);

	packet_set_fde(transport->packet, transport->socket->event.fde);
	packet_set_serialise(transport->packet);

	talloc_set_destructor(transport, transport_destructor);

	return transport;
}

/*
  mark the transport as dead
*/
void smb2_transport_dead(struct smb2_transport *transport, NTSTATUS status)
{
	smbcli_sock_dead(transport->socket);

	if (NT_STATUS_EQUAL(NT_STATUS_UNSUCCESSFUL, status)) {
		status = NT_STATUS_UNEXPECTED_NETWORK_ERROR;
	}

	/* kill all pending receives */
	while (transport->pending_recv) {
		struct smb2_request *req = transport->pending_recv;
		req->state = SMB2_REQUEST_ERROR;
		req->status = status;
		DLIST_REMOVE(transport->pending_recv, req);
		if (req->async.fn) {
			req->async.fn(req);
		}
	}
}

static NTSTATUS smb2_handle_oplock_break(struct smb2_transport *transport,
					 const DATA_BLOB *blob)
{
	uint8_t *hdr;
	uint16_t opcode;

	hdr = blob->data+NBT_HDR_SIZE;

	if (blob->length < (SMB2_MIN_SIZE+0x18)) {
		DEBUG(1,("Discarding smb2 oplock reply of size %u\n",
			 (unsigned)blob->length));
		return NT_STATUS_INVALID_NETWORK_RESPONSE;
	}

	opcode	= SVAL(hdr, SMB2_HDR_OPCODE);

	if (opcode != SMB2_OP_BREAK) {
		return NT_STATUS_INVALID_NETWORK_RESPONSE;
	}

	if (transport->oplock.handler) {
		uint8_t *body = hdr+SMB2_HDR_BODY;
		struct smb2_handle h;
		uint8_t level;

		level = CVAL(body, 0x02);
		smb2_pull_handle(body+0x08, &h);

		transport->oplock.handler(transport, &h, level,
					  transport->oplock.private_data);
	} else {
		DEBUG(5,("Got SMB2 oplock break with no handler\n"));
	}

	return NT_STATUS_OK;
}

/*
  we have a full request in our receive buffer - match it to a pending request
  and process
 */
static NTSTATUS smb2_transport_finish_recv(void *private, DATA_BLOB blob)
{
	struct smb2_transport *transport = talloc_get_type(private, 
							     struct smb2_transport);
	uint8_t *buffer, *hdr;
	int len;
	struct smb2_request *req = NULL;
	uint64_t seqnum;
	uint32_t flags;
	uint16_t buffer_code;
	uint32_t dynamic_size;
	uint32_t i;
	NTSTATUS status;

	buffer = blob.data;
	len = blob.length;

	hdr = buffer+NBT_HDR_SIZE;

	if (len < SMB2_MIN_SIZE) {
		DEBUG(1,("Discarding smb2 reply of size %d\n", len));
		goto error;
	}

	flags	= IVAL(hdr, SMB2_HDR_FLAGS);
	seqnum	= BVAL(hdr, SMB2_HDR_MESSAGE_ID);

	/* see MS-SMB2 3.2.5.19 */
	if (seqnum == UINT64_MAX) {
		return smb2_handle_oplock_break(transport, &blob);
	}

	/* match the incoming request against the list of pending requests */
	for (req=transport->pending_recv; req; req=req->next) {
		if (req->seqnum == seqnum) break;
	}

	if (!req) {
		DEBUG(1,("Discarding unmatched reply with seqnum 0x%llx op %d\n", 
			 (long long)seqnum, SVAL(hdr, SMB2_HDR_OPCODE)));
		goto error;
	}

	/* fill in the 'in' portion of the matching request */
	req->in.buffer = buffer;
	talloc_steal(req, buffer);
	req->in.size = len;
	req->in.allocated = req->in.size;

	req->in.hdr       = hdr;
	req->in.body      = hdr+SMB2_HDR_BODY;
	req->in.body_size = req->in.size - (SMB2_HDR_BODY+NBT_HDR_SIZE);
	req->status       = NT_STATUS(IVAL(hdr, SMB2_HDR_STATUS));

	if ((flags & SMB2_HDR_FLAG_ASYNC) &&
	    NT_STATUS_EQUAL(req->status, STATUS_PENDING)) {
		req->cancel.can_cancel = true;
		req->cancel.pending_id = IVAL(hdr, SMB2_HDR_PID);
		for (i=0; i< req->cancel.do_cancel; i++) {
			smb2_cancel(req);
		}
		talloc_free(buffer);
		return NT_STATUS_OK;
	}

	if (req->session && req->session->signing_active) {
		status = smb2_check_signature(&req->in, 
					      req->session->session_key);
		if (!NT_STATUS_IS_OK(status)) {
			/* the spec says to ignore packets with a bad signature */
			talloc_free(buffer);
			return status;
		}
	}

	buffer_code = SVAL(req->in.body, 0);
	req->in.body_fixed = (buffer_code & ~1);
	req->in.dynamic = NULL;
	dynamic_size = req->in.body_size - req->in.body_fixed;
	if (dynamic_size != 0 && (buffer_code & 1)) {
		req->in.dynamic = req->in.body + req->in.body_fixed;
		if (smb2_oob(&req->in, req->in.dynamic, dynamic_size)) {
			DEBUG(1,("SMB2 request invalid dynamic size 0x%x\n", 
				 dynamic_size));
			goto error;
		}
	}

	smb2_setup_bufinfo(req);

	DEBUG(2, ("SMB2 RECV seqnum=0x%llx\n", (long long)req->seqnum));
	dump_data(5, req->in.body, req->in.body_size);

	/* if this request has an async handler then call that to
	   notify that the reply has been received. This might destroy
	   the request so it must happen last */
	DLIST_REMOVE(transport->pending_recv, req);
	req->state = SMB2_REQUEST_DONE;
	if (req->async.fn) {
		req->async.fn(req);
	}
	return NT_STATUS_OK;

error:
	dump_data(5, buffer, len);
	if (req) {
		DLIST_REMOVE(transport->pending_recv, req);
		req->state = SMB2_REQUEST_ERROR;
		if (req->async.fn) {
			req->async.fn(req);
		}
	} else {
		talloc_free(buffer);
	}
	return NT_STATUS_UNSUCCESSFUL;
}

/*
  handle timeouts of individual smb requests
*/
static void smb2_timeout_handler(struct event_context *ev, struct timed_event *te, 
				 struct timeval t, void *private)
{
	struct smb2_request *req = talloc_get_type(private, struct smb2_request);

	if (req->state == SMB2_REQUEST_RECV) {
		DLIST_REMOVE(req->transport->pending_recv, req);
	}
	req->status = NT_STATUS_IO_TIMEOUT;
	req->state = SMB2_REQUEST_ERROR;
	if (req->async.fn) {
		req->async.fn(req);
	}
}


/*
  destroy a request
*/
static int smb2_request_destructor(struct smb2_request *req)
{
	if (req->state == SMB2_REQUEST_RECV) {
		DLIST_REMOVE(req->transport->pending_recv, req);
	}
	return 0;
}


/*
  put a request into the send queue
*/
void smb2_transport_send(struct smb2_request *req)
{
	DATA_BLOB blob;
	NTSTATUS status;

	_smb2_setlen(req->out.buffer, req->out.size - NBT_HDR_SIZE);

	DEBUG(2, ("SMB2 send seqnum=0x%llx\n", (long long)req->seqnum));
	dump_data(5, req->out.body, req->out.body_size);

	/* check if the transport is dead */
	if (req->transport->socket->sock == NULL) {
		req->state = SMB2_REQUEST_ERROR;
		req->status = NT_STATUS_NET_WRITE_FAULT;
		return;
	}

	/* possibly sign the message */
	if (req->session && req->session->signing_active) {
		status = smb2_sign_message(&req->out, req->session->session_key);
		if (!NT_STATUS_IS_OK(status)) {
			req->state = SMB2_REQUEST_ERROR;
			req->status = status;
			return;
		}
	}
	
	blob = data_blob_const(req->out.buffer, req->out.size);
	status = packet_send(req->transport->packet, blob);
	if (!NT_STATUS_IS_OK(status)) {
		req->state = SMB2_REQUEST_ERROR;
		req->status = status;
		return;
	}

	req->state = SMB2_REQUEST_RECV;
	DLIST_ADD(req->transport->pending_recv, req);

	/* add a timeout */
	if (req->transport->options.request_timeout) {
		event_add_timed(req->transport->socket->event.ctx, req, 
				timeval_current_ofs(req->transport->options.request_timeout, 0), 
				smb2_timeout_handler, req);
	}

	talloc_set_destructor(req, smb2_request_destructor);
}

static void idle_handler(struct event_context *ev, 
			 struct timed_event *te, struct timeval t, void *private)
{
	struct smb2_transport *transport = talloc_get_type(private,
							   struct smb2_transport);
	struct timeval next = timeval_add(&t, 0, transport->idle.period);
	transport->socket->event.te = event_add_timed(transport->socket->event.ctx, 
						      transport,
						      next,
						      idle_handler, transport);
	transport->idle.func(transport, transport->idle.private);
}

/*
  setup the idle handler for a transport
  the period is in microseconds
*/
void smb2_transport_idle_handler(struct smb2_transport *transport, 
				 void (*idle_func)(struct smb2_transport *, void *),
				 uint64_t period,
				 void *private)
{
	transport->idle.func = idle_func;
	transport->idle.private = private;
	transport->idle.period = period;

	if (transport->socket->event.te != NULL) {
		talloc_free(transport->socket->event.te);
	}

	transport->socket->event.te = event_add_timed(transport->socket->event.ctx, 
						      transport,
						      timeval_current_ofs(0, period),
						      idle_handler, transport);
}