s4:libcli/smb2: don't try to check the signing if we got NT_STATUS_USER_SESSION_DELETED
[amitay/samba.git] / source4 / libcli / smb2 / transport.c
1 /* 
2    Unix SMB/CIFS implementation.
3
4    SMB2 client transport context management functions
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 "libcli/raw/libcliraw.h"
24 #include "libcli/raw/raw_proto.h"
25 #include "libcli/smb2/smb2.h"
26 #include "libcli/smb2/smb2_calls.h"
27 #include "lib/socket/socket.h"
28 #include "lib/events/events.h"
29 #include "lib/stream/packet.h"
30 #include "../lib/util/dlinklist.h"
31
32
33 /*
34   an event has happened on the socket
35 */
36 static void smb2_transport_event_handler(struct tevent_context *ev, 
37                                          struct tevent_fd *fde, 
38                                          uint16_t flags, void *private_data)
39 {
40         struct smb2_transport *transport = talloc_get_type(private_data,
41                                                            struct smb2_transport);
42         if (flags & TEVENT_FD_READ) {
43                 packet_recv(transport->packet);
44                 return;
45         }
46         if (flags & TEVENT_FD_WRITE) {
47                 packet_queue_run(transport->packet);
48         }
49 }
50
51 /*
52   destroy a transport
53  */
54 static int transport_destructor(struct smb2_transport *transport)
55 {
56         smb2_transport_dead(transport, NT_STATUS_LOCAL_DISCONNECT);
57         return 0;
58 }
59
60
61 /*
62   handle receive errors
63 */
64 static void smb2_transport_error(void *private_data, NTSTATUS status)
65 {
66         struct smb2_transport *transport = talloc_get_type(private_data,
67                                                            struct smb2_transport);
68         smb2_transport_dead(transport, status);
69 }
70
71 static NTSTATUS smb2_transport_finish_recv(void *private_data, DATA_BLOB blob);
72
73 /*
74   create a transport structure based on an established socket
75 */
76 struct smb2_transport *smb2_transport_init(struct smbcli_socket *sock,
77                                            TALLOC_CTX *parent_ctx,
78                                            struct smbcli_options *options)
79 {
80         struct smb2_transport *transport;
81
82         transport = talloc_zero(parent_ctx, struct smb2_transport);
83         if (!transport) return NULL;
84
85         transport->socket = talloc_steal(transport, sock);
86         transport->options = *options;
87         transport->credits.charge = 0;
88         transport->credits.ask_num = 1;
89
90         /* setup the stream -> packet parser */
91         transport->packet = packet_init(transport);
92         if (transport->packet == NULL) {
93                 talloc_free(transport);
94                 return NULL;
95         }
96         packet_set_private(transport->packet, transport);
97         packet_set_socket(transport->packet, transport->socket->sock);
98         packet_set_callback(transport->packet, smb2_transport_finish_recv);
99         packet_set_full_request(transport->packet, packet_full_request_nbt);
100         packet_set_error_handler(transport->packet, smb2_transport_error);
101         packet_set_event_context(transport->packet, transport->socket->event.ctx);
102         packet_set_nofree(transport->packet);
103
104         /* take over event handling from the socket layer - it only
105            handles events up until we are connected */
106         talloc_free(transport->socket->event.fde);
107         transport->socket->event.fde = tevent_add_fd(transport->socket->event.ctx,
108                                                     transport->socket,
109                                                     socket_get_fd(transport->socket->sock),
110                                                     TEVENT_FD_READ,
111                                                     smb2_transport_event_handler,
112                                                     transport);
113
114         packet_set_fde(transport->packet, transport->socket->event.fde);
115         packet_set_serialise(transport->packet);
116
117         talloc_set_destructor(transport, transport_destructor);
118
119         return transport;
120 }
121
122 /*
123   mark the transport as dead
124 */
125 void smb2_transport_dead(struct smb2_transport *transport, NTSTATUS status)
126 {
127         smbcli_sock_dead(transport->socket);
128
129         if (NT_STATUS_EQUAL(NT_STATUS_UNSUCCESSFUL, status)) {
130                 status = NT_STATUS_UNEXPECTED_NETWORK_ERROR;
131         }
132
133         /* kill all pending receives */
134         while (transport->pending_recv) {
135                 struct smb2_request *req = transport->pending_recv;
136                 req->state = SMB2_REQUEST_ERROR;
137                 req->status = status;
138                 DLIST_REMOVE(transport->pending_recv, req);
139                 if (req->async.fn) {
140                         req->async.fn(req);
141                 }
142         }
143 }
144
145 static NTSTATUS smb2_handle_oplock_break(struct smb2_transport *transport,
146                                          const DATA_BLOB *blob)
147 {
148         uint8_t *hdr;
149         uint8_t *body;
150         uint16_t len, bloblen;
151         bool lease;
152
153         hdr = blob->data+NBT_HDR_SIZE;
154         body = hdr+SMB2_HDR_BODY;
155         bloblen = blob->length - SMB2_HDR_BODY;
156
157         if (bloblen < 2) {
158                 DEBUG(1,("Discarding smb2 oplock reply of size %u\n",
159                         (unsigned)blob->length));
160                 return NT_STATUS_INVALID_NETWORK_RESPONSE;
161         }
162
163         len = CVAL(body, 0x00);
164         if (len > bloblen) {
165                 DEBUG(1,("Discarding smb2 oplock reply,"
166                         "packet claims %u byte body, only %u bytes seen\n",
167                         len, bloblen));
168                 return NT_STATUS_INVALID_NETWORK_RESPONSE;
169         }
170
171         if (len == 24) {
172                 lease = false;
173         } else if (len == 44) {
174                 lease = true;
175         } else {
176                 DEBUG(1,("Discarding smb2 oplock reply of invalid size %u\n",
177                         (unsigned)blob->length));
178                 return NT_STATUS_INVALID_NETWORK_RESPONSE;
179         }
180
181         if (!lease && transport->oplock.handler) {
182                 struct smb2_handle h;
183                 uint8_t level;
184
185                 level = CVAL(body, 0x02);
186                 smb2_pull_handle(body+0x08, &h);
187
188                 transport->oplock.handler(transport, &h, level,
189                                           transport->oplock.private_data);
190         } else if (lease && transport->lease.handler) {
191                 struct smb2_lease_break lb;
192
193                 ZERO_STRUCT(lb);
194                 lb.break_flags =                SVAL(body, 0x4);
195                 memcpy(&lb.current_lease.lease_key, body+0x8,
196                     sizeof(struct smb2_lease_key));
197                 lb.current_lease.lease_state =  SVAL(body, 0x18);
198                 lb.new_lease_state =            SVAL(body, 0x1C);
199                 lb.break_reason =               SVAL(body, 0x20);
200                 lb.access_mask_hint =           SVAL(body, 0x24);
201                 lb.share_mask_hint =            SVAL(body, 0x28);
202
203                 transport->lease.handler(transport, &lb,
204                     transport->lease.private_data);
205         } else {
206                 DEBUG(5,("Got SMB2 %s break with no handler\n",
207                         lease ? "lease" : "oplock"));
208         }
209
210         return NT_STATUS_OK;
211 }
212
213 struct smb2_transport_compount_response_state {
214         struct smb2_transport *transport;
215         DATA_BLOB blob;
216 };
217
218 static void smb2_transport_compound_response_handler(struct tevent_context *ctx,
219                                                      struct tevent_immediate *im,
220                                                      void *private_data)
221 {
222         struct smb2_transport_compount_response_state *state =
223                 talloc_get_type_abort(private_data,
224                 struct smb2_transport_compount_response_state);
225         struct smb2_transport *transport = state->transport;
226         NTSTATUS status;
227
228         status = smb2_transport_finish_recv(transport, state->blob);
229         TALLOC_FREE(state);
230         if (!NT_STATUS_IS_OK(status)) {
231                 smb2_transport_error(transport, status);
232         }
233 }
234
235 /*
236   we have a full request in our receive buffer - match it to a pending request
237   and process
238  */
239 static NTSTATUS smb2_transport_finish_recv(void *private_data, DATA_BLOB blob)
240 {
241         struct smb2_transport *transport = talloc_get_type(private_data,
242                                                              struct smb2_transport);
243         uint8_t *buffer, *hdr;
244         int len;
245         struct smb2_request *req = NULL;
246         uint64_t seqnum;
247         uint32_t flags;
248         uint16_t buffer_code;
249         uint32_t dynamic_size;
250         uint32_t i;
251         uint16_t opcode;
252         NTSTATUS status;
253         uint32_t next_ofs;
254
255         buffer = blob.data;
256         len = blob.length;
257
258         hdr = buffer+NBT_HDR_SIZE;
259
260         if (len < SMB2_MIN_SIZE) {
261                 DEBUG(1,("Discarding smb2 reply of size %d\n", len));
262                 goto error;
263         }
264
265         flags   = IVAL(hdr, SMB2_HDR_FLAGS);
266         seqnum  = BVAL(hdr, SMB2_HDR_MESSAGE_ID);
267         opcode  = SVAL(hdr, SMB2_HDR_OPCODE);
268
269         /* see MS-SMB2 3.2.5.19 */
270         if (seqnum == UINT64_MAX) {
271                 if (opcode != SMB2_OP_BREAK) {
272                         DEBUG(1,("Discarding packet with invalid seqnum, "
273                                 "opcode %u\n", opcode));
274                         return NT_STATUS_INVALID_NETWORK_RESPONSE;
275                 }
276
277                 return smb2_handle_oplock_break(transport, &blob);
278         }
279
280         /* match the incoming request against the list of pending requests */
281         for (req=transport->pending_recv; req; req=req->next) {
282                 if (req->seqnum == seqnum) break;
283         }
284
285         if (!req) {
286                 DEBUG(1,("Discarding unmatched reply with seqnum 0x%llx op %d\n", 
287                          (long long)seqnum, SVAL(hdr, SMB2_HDR_OPCODE)));
288                 goto error;
289         }
290
291         /* fill in the 'in' portion of the matching request */
292         req->in.buffer = buffer;
293         talloc_steal(req, buffer);
294         req->in.size = len;
295         req->in.allocated = req->in.size;
296
297         req->in.hdr       = hdr;
298         req->in.body      = hdr+SMB2_HDR_BODY;
299         req->in.body_size = req->in.size - (SMB2_HDR_BODY+NBT_HDR_SIZE);
300         req->status       = NT_STATUS(IVAL(hdr, SMB2_HDR_STATUS));
301
302         if ((flags & SMB2_HDR_FLAG_ASYNC) &&
303             NT_STATUS_EQUAL(req->status, STATUS_PENDING)) {
304                 req->cancel.can_cancel = true;
305                 req->cancel.async_id = BVAL(hdr, SMB2_HDR_ASYNC_ID);
306                 for (i=0; i< req->cancel.do_cancel; i++) {
307                         smb2_cancel(req);
308                 }
309                 talloc_free(buffer);
310                 return NT_STATUS_OK;
311         }
312
313         next_ofs = IVAL(req->in.hdr, SMB2_HDR_NEXT_COMMAND);
314         if (next_ofs > 0) {
315                 if (smb2_oob(&req->in, req->in.hdr + next_ofs, SMB2_HDR_BODY + 2)) {
316                         DEBUG(1,("SMB2 request invalid next offset 0x%x\n",
317                                  next_ofs));
318                         goto error;
319                 }
320
321                 req->in.size = NBT_HDR_SIZE + next_ofs;
322                 req->in.body_size = req->in.size - (SMB2_HDR_BODY+NBT_HDR_SIZE);
323         }
324
325         if (req->session && req->session->signing_active &&
326             !NT_STATUS_EQUAL(req->status, NT_STATUS_USER_SESSION_DELETED)) {
327                 status = smb2_check_signature(&req->in, 
328                                               req->session->session_key);
329                 if (!NT_STATUS_IS_OK(status)) {
330                         /* the spec says to ignore packets with a bad signature */
331                         talloc_free(buffer);
332                         return status;
333                 }
334         }
335
336         buffer_code = SVAL(req->in.body, 0);
337         req->in.body_fixed = (buffer_code & ~1);
338         req->in.dynamic = NULL;
339         dynamic_size = req->in.body_size - req->in.body_fixed;
340         if (dynamic_size != 0 && (buffer_code & 1)) {
341                 req->in.dynamic = req->in.body + req->in.body_fixed;
342                 if (smb2_oob(&req->in, req->in.dynamic, dynamic_size)) {
343                         DEBUG(1,("SMB2 request invalid dynamic size 0x%x\n", 
344                                  dynamic_size));
345                         goto error;
346                 }
347         }
348
349         smb2_setup_bufinfo(req);
350
351         DEBUG(2, ("SMB2 RECV seqnum=0x%llx\n", (long long)req->seqnum));
352         dump_data(5, req->in.body, req->in.body_size);
353
354         if (next_ofs > 0) {
355                 struct tevent_immediate *im;
356                 struct smb2_transport_compount_response_state *state;
357
358                 state = talloc(transport,
359                                struct smb2_transport_compount_response_state);
360                 if (!state) {
361                         goto error;
362                 }
363                 state->transport = transport;
364
365                 state->blob = data_blob_talloc(state, NULL,
366                                                blob.length - next_ofs);
367                 if (!state->blob.data) {
368                         goto error;
369                 }
370                 im = tevent_create_immediate(state);
371                 if (!im) {
372                         TALLOC_FREE(state);
373                         goto error;
374                 }
375                 _smb2_setlen(state->blob.data, state->blob.length - NBT_HDR_SIZE);
376                 memcpy(state->blob.data + NBT_HDR_SIZE,
377                        req->in.hdr + next_ofs,
378                        req->in.allocated - req->in.size);
379                 tevent_schedule_immediate(im, transport->socket->event.ctx,
380                                           smb2_transport_compound_response_handler,
381                                           state);
382         }
383
384         /* if this request has an async handler then call that to
385            notify that the reply has been received. This might destroy
386            the request so it must happen last */
387         DLIST_REMOVE(transport->pending_recv, req);
388         req->state = SMB2_REQUEST_DONE;
389         if (req->async.fn) {
390                 req->async.fn(req);
391         }
392         return NT_STATUS_OK;
393
394 error:
395         dump_data(5, buffer, len);
396         if (req) {
397                 DLIST_REMOVE(transport->pending_recv, req);
398                 req->state = SMB2_REQUEST_ERROR;
399                 if (req->async.fn) {
400                         req->async.fn(req);
401                 }
402         } else {
403                 talloc_free(buffer);
404         }
405         return NT_STATUS_UNSUCCESSFUL;
406 }
407
408 /*
409   handle timeouts of individual smb requests
410 */
411 static void smb2_timeout_handler(struct tevent_context *ev, struct tevent_timer *te, 
412                                  struct timeval t, void *private_data)
413 {
414         struct smb2_request *req = talloc_get_type(private_data, struct smb2_request);
415
416         if (req->state == SMB2_REQUEST_RECV) {
417                 DLIST_REMOVE(req->transport->pending_recv, req);
418         }
419         req->status = NT_STATUS_IO_TIMEOUT;
420         req->state = SMB2_REQUEST_ERROR;
421         if (req->async.fn) {
422                 req->async.fn(req);
423         }
424 }
425
426
427 /*
428   destroy a request
429 */
430 static int smb2_request_destructor(struct smb2_request *req)
431 {
432         if (req->state == SMB2_REQUEST_RECV) {
433                 DLIST_REMOVE(req->transport->pending_recv, req);
434         }
435         return 0;
436 }
437
438 static NTSTATUS smb2_transport_raw_send(struct smb2_transport *transport,
439                                         struct smb2_request_buffer *buffer)
440 {
441         DATA_BLOB blob;
442         NTSTATUS status;
443
444         /* check if the transport is dead */
445         if (transport->socket->sock == NULL) {
446                 return NT_STATUS_NET_WRITE_FAULT;
447         }
448
449         _smb2_setlen(buffer->buffer, buffer->size - NBT_HDR_SIZE);
450         blob = data_blob_const(buffer->buffer, buffer->size);
451         status = packet_send(transport->packet, blob);
452         if (!NT_STATUS_IS_OK(status)) {
453                 return status;
454         }
455
456         return NT_STATUS_OK;
457 }
458
459 /*
460   put a request into the send queue
461 */
462 void smb2_transport_send(struct smb2_request *req)
463 {
464         NTSTATUS status;
465
466         DEBUG(2, ("SMB2 send seqnum=0x%llx\n", (long long)req->seqnum));
467         dump_data(5, req->out.body, req->out.body_size);
468
469         if (req->transport->compound.missing > 0) {
470                 off_t next_ofs;
471                 size_t pad = 0;
472                 uint8_t *end;
473
474                 end = req->out.buffer + req->out.size;
475
476                 /*
477                  * we need to set dynamic otherwise
478                  * smb2_grow_buffer segfaults
479                  */
480                 if (req->out.dynamic == NULL) {
481                         req->out.dynamic = end;
482                 }
483
484                 next_ofs = end - req->out.hdr;
485                 if ((next_ofs % 8) > 0) {
486                         pad = 8 - (next_ofs % 8);
487                 }
488                 next_ofs += pad;
489
490                 status = smb2_grow_buffer(&req->out, pad);
491                 if (!NT_STATUS_IS_OK(status)) {
492                         req->state = SMB2_REQUEST_ERROR;
493                         req->status = status;
494                         return;
495                 }
496                 req->out.size += pad;
497
498                 SIVAL(req->out.hdr, SMB2_HDR_NEXT_COMMAND, next_ofs);
499         }
500
501         /* possibly sign the message */
502         if (req->session && req->session->signing_active) {
503                 status = smb2_sign_message(&req->out, req->session->session_key);
504                 if (!NT_STATUS_IS_OK(status)) {
505                         req->state = SMB2_REQUEST_ERROR;
506                         req->status = status;
507                         return;
508                 }
509         }
510
511         if (req->transport->compound.missing > 0) {
512                 req->transport->compound.buffer = req->out;
513         } else {
514                 status = smb2_transport_raw_send(req->transport,
515                                                  &req->out);
516                 if (!NT_STATUS_IS_OK(status)) {
517                         req->state = SMB2_REQUEST_ERROR;
518                         req->status = status;
519                         return;
520                 }
521         }
522         ZERO_STRUCT(req->out);
523
524         req->state = SMB2_REQUEST_RECV;
525         DLIST_ADD(req->transport->pending_recv, req);
526
527         /* add a timeout */
528         if (req->transport->options.request_timeout) {
529                 tevent_add_timer(req->transport->socket->event.ctx, req,
530                                 timeval_current_ofs(req->transport->options.request_timeout, 0), 
531                                 smb2_timeout_handler, req);
532         }
533
534         talloc_set_destructor(req, smb2_request_destructor);
535 }
536
537 NTSTATUS smb2_transport_compound_start(struct smb2_transport *transport,
538                                        uint32_t num)
539 {
540         ZERO_STRUCT(transport->compound);
541         transport->compound.missing = num;
542         return NT_STATUS_OK;
543 }
544
545 void smb2_transport_compound_set_related(struct smb2_transport *transport,
546                                          bool related)
547 {
548         transport->compound.related = related;
549 }
550
551 void smb2_transport_credits_ask_num(struct smb2_transport *transport,
552                                     uint16_t ask_num)
553 {
554         transport->credits.ask_num = ask_num;
555 }
556
557 void smb2_transport_credits_set_charge(struct smb2_transport *transport,
558                                        uint16_t charge)
559 {
560         transport->credits.charge = charge;
561 }
562
563 static void idle_handler(struct tevent_context *ev, 
564                          struct tevent_timer *te, struct timeval t, void *private_data)
565 {
566         struct smb2_transport *transport = talloc_get_type(private_data,
567                                                            struct smb2_transport);
568         struct timeval next = timeval_add(&t, 0, transport->idle.period);
569         transport->socket->event.te = tevent_add_timer(transport->socket->event.ctx,
570                                                       transport,
571                                                       next,
572                                                       idle_handler, transport);
573         transport->idle.func(transport, transport->idle.private_data);
574 }
575
576 /*
577   setup the idle handler for a transport
578   the period is in microseconds
579 */
580 void smb2_transport_idle_handler(struct smb2_transport *transport, 
581                                  void (*idle_func)(struct smb2_transport *, void *),
582                                  uint64_t period,
583                                  void *private_data)
584 {
585         transport->idle.func = idle_func;
586         transport->idle.private_data = private_data;
587         transport->idle.period = period;
588
589         if (transport->socket->event.te != NULL) {
590                 talloc_free(transport->socket->event.te);
591         }
592
593         transport->socket->event.te = tevent_add_timer(transport->socket->event.ctx,
594                                                       transport,
595                                                       timeval_current_ofs(0, period),
596                                                       idle_handler, transport);
597 }