summaryrefslogtreecommitdiff
path: root/source3/libsmb/clientgen.c
blob: 1a6fb8f93fb9149dfe4ce1377a861f05ca74582d (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
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
/* 
   Unix SMB/CIFS implementation.
   SMB client generic functions
   Copyright (C) Andrew Tridgell 1994-1998
   Copyright (C) Jeremy Allison 2007.
   
   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"

/****************************************************************************
 Change the timeout (in milliseconds).
****************************************************************************/

unsigned int cli_set_timeout(struct cli_state *cli, unsigned int timeout)
{
	unsigned int old_timeout = cli->timeout;
	cli->timeout = timeout;
	return old_timeout;
}

/****************************************************************************
 Change the port number used to call on.
****************************************************************************/

int cli_set_port(struct cli_state *cli, int port)
{
	cli->port = port;
	return port;
}

/****************************************************************************
 Read an smb from a fd ignoring all keepalive packets. Note that the buffer 
 *MUST* be of size BUFFER_SIZE+SAFETY_MARGIN.
 The timeout is in milliseconds

 This is exactly the same as receive_smb except that it never returns
 a session keepalive packet (just as receive_smb used to do).
 receive_smb was changed to return keepalives as the oplock processing means this call
 should never go into a blocking read.
****************************************************************************/

static ssize_t client_receive_smb(struct cli_state *cli, size_t maxlen)
{
	ssize_t len;

	for(;;) {
		len = receive_smb_raw(cli->fd, cli->inbuf, cli->timeout,
				maxlen, &cli->smb_rw_error);

		if (len < 0) {
			DEBUG(10,("client_receive_smb failed\n"));
			show_msg(cli->inbuf);
			return len;
		}

		/* Ignore session keepalive packets. */
		if(CVAL(cli->inbuf,0) != SMBkeepalive) {
			break;
		}
	}
	show_msg(cli->inbuf);
	return len;
}

/****************************************************************************
 Recv an smb.
****************************************************************************/

bool cli_receive_smb(struct cli_state *cli)
{
	ssize_t len;

	/* fd == -1 causes segfaults -- Tom (tom@ninja.nl) */
	if (cli->fd == -1)
		return False; 

 again:
	len = client_receive_smb(cli, 0);
	
	if (len > 0) {
		/* it might be an oplock break request */
		if (!(CVAL(cli->inbuf, smb_flg) & FLAG_REPLY) &&
		    CVAL(cli->inbuf,smb_com) == SMBlockingX &&
		    SVAL(cli->inbuf,smb_vwv6) == 0 &&
		    SVAL(cli->inbuf,smb_vwv7) == 0) {
			if (cli->oplock_handler) {
				int fnum = SVAL(cli->inbuf,smb_vwv2);
				unsigned char level = CVAL(cli->inbuf,smb_vwv3+1);
				if (!cli->oplock_handler(cli, fnum, level)) {
					return False;
				}
			}
			/* try to prevent loops */
			SCVAL(cli->inbuf,smb_com,0xFF);
			goto again;
		}
	}

	/* If the server is not responding, note that now */
	if (len < 0) {
                DEBUG(0, ("Receiving SMB: Server stopped responding\n"));
		close(cli->fd);
		cli->fd = -1;
		return False;
	}

	if (!cli_check_sign_mac(cli)) {
		/*
		 * If we get a signature failure in sessionsetup, then
		 * the server sometimes just reflects the sent signature
		 * back to us. Detect this and allow the upper layer to
		 * retrieve the correct Windows error message.
		 */
		if (CVAL(cli->outbuf,smb_com) == SMBsesssetupX &&
			(smb_len(cli->inbuf) > (smb_ss_field + 8 - 4)) &&
			(SVAL(cli->inbuf,smb_flg2) & FLAGS2_SMB_SECURITY_SIGNATURES) &&
			memcmp(&cli->outbuf[smb_ss_field],&cli->inbuf[smb_ss_field],8) == 0 &&
			cli_is_error(cli)) {

			/*
			 * Reflected signature on login error. 
			 * Set bad sig but don't close fd.
			 */
			cli->smb_rw_error = SMB_READ_BAD_SIG;
			return True;
		}

		DEBUG(0, ("SMB Signature verification failed on incoming packet!\n"));
		cli->smb_rw_error = SMB_READ_BAD_SIG;
		close(cli->fd);
		cli->fd = -1;
		return False;
	};
	return True;
}

/****************************************************************************
 Read the data portion of a readX smb.
 The timeout is in milliseconds
****************************************************************************/

ssize_t cli_receive_smb_data(struct cli_state *cli, char *buffer, size_t len)
{
	if (cli->timeout > 0) {
		return read_socket_with_timeout(cli->fd, buffer, len,
						len, cli->timeout, &cli->smb_rw_error);
	} else {
		return read_data(cli->fd, buffer, len, &cli->smb_rw_error);
	}
}

/****************************************************************************
 Read a smb readX header.
****************************************************************************/

bool cli_receive_smb_readX_header(struct cli_state *cli)
{
	ssize_t len, offset;

	if (cli->fd == -1)
		return False; 

 again:

	/* Read up to the size of a readX header reply. */
	len = client_receive_smb(cli, (smb_size - 4) + 24);
	
	if (len > 0) {
		/* it might be an oplock break request */
		if (!(CVAL(cli->inbuf, smb_flg) & FLAG_REPLY) &&
		    CVAL(cli->inbuf,smb_com) == SMBlockingX &&
		    SVAL(cli->inbuf,smb_vwv6) == 0 &&
		    SVAL(cli->inbuf,smb_vwv7) == 0) {
			ssize_t total_len = smb_len(cli->inbuf);

			if (total_len > CLI_SAMBA_MAX_LARGE_READX_SIZE+SAFETY_MARGIN) {
				goto read_err;
			}

			/* Read the rest of the data. */
			if ((total_len - len > 0) &&
			    !cli_receive_smb_data(cli,cli->inbuf+len,total_len - len)) {
				goto read_err;
			}

			if (cli->oplock_handler) {
				int fnum = SVAL(cli->inbuf,smb_vwv2);
				unsigned char level = CVAL(cli->inbuf,smb_vwv3+1);
				if (!cli->oplock_handler(cli, fnum, level)) return False;
			}
			/* try to prevent loops */
			SCVAL(cli->inbuf,smb_com,0xFF);
			goto again;
		}
	}

	/* If it's not the above size it probably was an error packet. */

	if ((len == (smb_size - 4) + 24) && !cli_is_error(cli)) {
		/* Check it's a non-chained readX reply. */
		if (!(CVAL(cli->inbuf, smb_flg) & FLAG_REPLY) ||
			(CVAL(cli->inbuf,smb_vwv0) != 0xFF) ||
			(CVAL(cli->inbuf,smb_com) != SMBreadX)) {
			/* 
			 * We're not coping here with asnyc replies to
			 * other calls. Punt here - we need async client
			 * libs for this.
			 */
			goto read_err;
		}

		/* 
		 * We know it's a readX reply - ensure we've read the
		 * padding bytes also.
		 */

		offset = SVAL(cli->inbuf,smb_vwv6);
		if (offset > len) {
			ssize_t ret;
			size_t padbytes = offset - len;
			ret = cli_receive_smb_data(cli,smb_buf(cli->inbuf),padbytes);
			if (ret != padbytes) {
				goto read_err;
			}
		}
	}

	return True;

  read_err:

	cli->smb_rw_error = SMB_READ_ERROR;
	close(cli->fd);
	cli->fd = -1;
	return False;
}

static ssize_t write_socket(int fd, const char *buf, size_t len)
{
        ssize_t ret=0;

        DEBUG(6,("write_socket(%d,%d)\n",fd,(int)len));
        ret = write_data(fd,buf,len);

        DEBUG(6,("write_socket(%d,%d) wrote %d\n",fd,(int)len,(int)ret));
        if(ret <= 0)
                DEBUG(0,("write_socket: Error writing %d bytes to socket %d: ERRNO = %s\n",
                        (int)len, fd, strerror(errno) ));

        return(ret);
}

/****************************************************************************
 Send an smb to a fd.
****************************************************************************/

bool cli_send_smb(struct cli_state *cli)
{
	size_t len;
	size_t nwritten=0;
	ssize_t ret;

	/* fd == -1 causes segfaults -- Tom (tom@ninja.nl) */
	if (cli->fd == -1)
		return False;

	cli_calculate_sign_mac(cli);

	len = smb_len(cli->outbuf) + 4;

	while (nwritten < len) {
		ret = write_socket(cli->fd,cli->outbuf+nwritten,len - nwritten);
		if (ret <= 0) {
			close(cli->fd);
			cli->fd = -1;
			cli->smb_rw_error = SMB_WRITE_ERROR;
			DEBUG(0,("Error writing %d bytes to client. %d (%s)\n",
				(int)len,(int)ret, strerror(errno) ));
			return False;
		}
		nwritten += ret;
	}
	/* Increment the mid so we can tell between responses. */
	cli->mid++;
	if (!cli->mid)
		cli->mid++;
	return True;
}

/****************************************************************************
 Send a "direct" writeX smb to a fd.
****************************************************************************/

bool cli_send_smb_direct_writeX(struct cli_state *cli,
				const char *p,
				size_t extradata)
{
	/* First length to send is the offset to the data. */
	size_t len = SVAL(cli->outbuf,smb_vwv11) + 4;
	size_t nwritten=0;
	ssize_t ret;

	/* fd == -1 causes segfaults -- Tom (tom@ninja.nl) */
	if (cli->fd == -1) {
		return false;
	}

	if (client_is_signing_on(cli)) {
		DEBUG(0,("cli_send_smb_large: cannot send signed packet.\n"));
		return false;
	}

	while (nwritten < len) {
		ret = write_socket(cli->fd,cli->outbuf+nwritten,len - nwritten);
		if (ret <= 0) {
			close(cli->fd);
			cli->fd = -1;
			cli->smb_rw_error = SMB_WRITE_ERROR;
			DEBUG(0,("Error writing %d bytes to client. %d (%s)\n",
				(int)len,(int)ret, strerror(errno) ));
			return false;
		}
		nwritten += ret;
	}

	/* Now write the extra data. */
	nwritten=0;
	while (nwritten < extradata) {
		ret = write_socket(cli->fd,p+nwritten,extradata - nwritten);
		if (ret <= 0) {
			close(cli->fd);
			cli->fd = -1;
			cli->smb_rw_error = SMB_WRITE_ERROR;
			DEBUG(0,("Error writing %d extradata "
				"bytes to client. %d (%s)\n",
				(int)extradata,(int)ret, strerror(errno) ));
			return False;
		}
		nwritten += ret;
	}

	/* Increment the mid so we can tell between responses. */
	cli->mid++;
	if (!cli->mid)
		cli->mid++;
	return true;
}

/****************************************************************************
 Setup basics in a outgoing packet.
****************************************************************************/

void cli_setup_packet(struct cli_state *cli)
{
	cli->rap_error = 0;
	SSVAL(cli->outbuf,smb_pid,cli->pid);
	SSVAL(cli->outbuf,smb_uid,cli->vuid);
	SSVAL(cli->outbuf,smb_mid,cli->mid);
	if (cli->protocol > PROTOCOL_CORE) {
		uint16 flags2;
		if (cli->case_sensitive) {
			SCVAL(cli->outbuf,smb_flg,0x0);
		} else {
			/* Default setting, case insensitive. */
			SCVAL(cli->outbuf,smb_flg,0x8);
		}
		flags2 = FLAGS2_LONG_PATH_COMPONENTS;
		if (cli->capabilities & CAP_UNICODE)
			flags2 |= FLAGS2_UNICODE_STRINGS;
		if ((cli->capabilities & CAP_DFS) && cli->dfsroot)
			flags2 |= FLAGS2_DFS_PATHNAMES;
		if (cli->capabilities & CAP_STATUS32)
			flags2 |= FLAGS2_32_BIT_ERROR_CODES;
		if (cli->use_spnego)
			flags2 |= FLAGS2_EXTENDED_SECURITY;
		SSVAL(cli->outbuf,smb_flg2, flags2);
	}
}

/****************************************************************************
 Setup the bcc length of the packet from a pointer to the end of the data.
****************************************************************************/

void cli_setup_bcc(struct cli_state *cli, void *p)
{
	set_message_bcc(cli->outbuf, PTR_DIFF(p, smb_buf(cli->outbuf)));
}

/****************************************************************************
 Initialise credentials of a client structure.
****************************************************************************/

void cli_init_creds(struct cli_state *cli, const char *username, const char *domain, const char *password)
{
	fstrcpy(cli->domain, domain);
	fstrcpy(cli->user_name, username);
	pwd_set_cleartext(&cli->pwd, password);
	if (!*username) {
		cli->pwd.null_pwd = True;
	}

        DEBUG(10,("cli_init_creds: user %s domain %s\n", cli->user_name, cli->domain));
}

/****************************************************************************
 Set the signing state (used from the command line).
****************************************************************************/

void cli_setup_signing_state(struct cli_state *cli, int signing_state)
{
	if (signing_state == Undefined)
		return;

	if (signing_state == False) {
		cli->sign_info.allow_smb_signing = False;
		cli->sign_info.mandatory_signing = False;
		return;
	}

	cli->sign_info.allow_smb_signing = True;

	if (signing_state == Required) 
		cli->sign_info.mandatory_signing = True;
}

/****************************************************************************
 Initialise a client structure. Always returns a malloc'ed struct.
****************************************************************************/

struct cli_state *cli_initialise(void)
{
	struct cli_state *cli = NULL;

	/* Check the effective uid - make sure we are not setuid */
	if (is_setuid_root()) {
		DEBUG(0,("libsmb based programs must *NOT* be setuid root.\n"));
		return NULL;
	}

	cli = SMB_MALLOC_P(struct cli_state);
	if (!cli) {
		return NULL;
	}

	ZERO_STRUCTP(cli);

	cli->port = 0;
	cli->fd = -1;
	cli->cnum = -1;
	cli->pid = (uint16)sys_getpid();
	cli->mid = 1;
	cli->vuid = UID_FIELD_INVALID;
	cli->protocol = PROTOCOL_NT1;
	cli->timeout = 20000; /* Timeout is in milliseconds. */
	cli->bufsize = CLI_BUFFER_SIZE+4;
	cli->max_xmit = cli->bufsize;
	cli->outbuf = (char *)SMB_MALLOC(cli->bufsize+SAFETY_MARGIN);
	cli->inbuf = (char *)SMB_MALLOC(cli->bufsize+SAFETY_MARGIN);
	cli->oplock_handler = cli_oplock_ack;
	cli->case_sensitive = False;
	cli->smb_rw_error = 0;

	cli->use_spnego = lp_client_use_spnego();

	cli->capabilities = CAP_UNICODE | CAP_STATUS32 | CAP_DFS;

	/* Set the CLI_FORCE_DOSERR environment variable to test
	   client routines using DOS errors instead of STATUS32
	   ones.  This intended only as a temporary hack. */	
	if (getenv("CLI_FORCE_DOSERR"))
		cli->force_dos_errors = True;

	if (lp_client_signing()) 
		cli->sign_info.allow_smb_signing = True;

	if (lp_client_signing() == Required) 
		cli->sign_info.mandatory_signing = True;
                                   
	if (!cli->outbuf || !cli->inbuf)
                goto error;

	memset(cli->outbuf, 0, cli->bufsize);
	memset(cli->inbuf, 0, cli->bufsize);


#if defined(DEVELOPER)
	/* just because we over-allocate, doesn't mean it's right to use it */
	clobber_region(FUNCTION_MACRO, __LINE__, cli->outbuf+cli->bufsize, SAFETY_MARGIN);
	clobber_region(FUNCTION_MACRO, __LINE__, cli->inbuf+cli->bufsize, SAFETY_MARGIN);
#endif

	/* initialise signing */
	cli_null_set_signing(cli);

	cli->initialised = 1;

	return cli;

        /* Clean up after malloc() error */

 error:

        SAFE_FREE(cli->inbuf);
        SAFE_FREE(cli->outbuf);
	SAFE_FREE(cli);
        return NULL;
}

/****************************************************************************
 External interface.
 Close an open named pipe over SMB. Free any authentication data.
 Returns False if the cli_close call failed.
 ****************************************************************************/

bool cli_rpc_pipe_close(struct rpc_pipe_client *cli)
{
	bool ret;

	if (!cli) {
		return False;
	}

	ret = cli_close(cli->cli, cli->fnum);

	if (!ret) {
		DEBUG(1,("cli_rpc_pipe_close: cli_close failed on pipe %s, "
                         "fnum 0x%x "
                         "to machine %s.  Error was %s\n",
                         cli->pipe_name,
                         (int) cli->fnum,
                         cli->cli->desthost,
                         cli_errstr(cli->cli)));
	}

	if (cli->auth.cli_auth_data_free_func) {
		(*cli->auth.cli_auth_data_free_func)(&cli->auth);
	}

	DEBUG(10,("cli_rpc_pipe_close: closed pipe %s to machine %s\n",
		cli->pipe_name, cli->cli->desthost ));

	DLIST_REMOVE(cli->cli->pipe_list, cli);
	talloc_destroy(cli->mem_ctx);
	return ret;
}

/****************************************************************************
 Close all pipes open on this session.
****************************************************************************/

void cli_nt_pipes_close(struct cli_state *cli)
{
	struct rpc_pipe_client *cp, *next;

	for (cp = cli->pipe_list; cp; cp = next) {
		next = cp->next;
		cli_rpc_pipe_close(cp);
	}
}

/****************************************************************************
 Shutdown a client structure.
****************************************************************************/

void cli_shutdown(struct cli_state *cli)
{
	cli_nt_pipes_close(cli);

	/*
	 * tell our peer to free his resources.  Wihtout this, when an
	 * application attempts to do a graceful shutdown and calls
	 * smbc_free_context() to clean up all connections, some connections
	 * can remain active on the peer end, until some (long) timeout period
	 * later.  This tree disconnect forces the peer to clean up, since the
	 * connection will be going away.
	 *
	 * Also, do not do tree disconnect when cli->smb_rw_error is SMB_DO_NOT_DO_TDIS
	 * the only user for this so far is smbmount which passes opened connection
	 * down to kernel's smbfs module.
	 */
	if ( (cli->cnum != (uint16)-1) && (cli->smb_rw_error != SMB_DO_NOT_DO_TDIS ) ) {
		cli_tdis(cli);
	}
        
	SAFE_FREE(cli->outbuf);
	SAFE_FREE(cli->inbuf);

	cli_free_signing_context(cli);
	data_blob_free(&cli->secblob);
	data_blob_free(&cli->user_session_key);

	if (cli->fd != -1) {
		close(cli->fd);
	}
	cli->fd = -1;
	cli->smb_rw_error = 0;

	SAFE_FREE(cli);
}

/****************************************************************************
 Set socket options on a open connection.
****************************************************************************/

void cli_sockopt(struct cli_state *cli, const char *options)
{
	set_socket_options(cli->fd, options);
}

/****************************************************************************
 Set the PID to use for smb messages. Return the old pid.
****************************************************************************/

uint16 cli_setpid(struct cli_state *cli, uint16 pid)
{
	uint16 ret = cli->pid;
	cli->pid = pid;
	return ret;
}

/****************************************************************************
 Set the case sensitivity flag on the packets. Returns old state.
****************************************************************************/

bool cli_set_case_sensitive(struct cli_state *cli, bool case_sensitive)
{
	bool ret = cli->case_sensitive;
	cli->case_sensitive = case_sensitive;
	return ret;
}

/****************************************************************************
Send a keepalive packet to the server
****************************************************************************/

bool cli_send_keepalive(struct cli_state *cli)
{
        if (cli->fd == -1) {
                DEBUG(3, ("cli_send_keepalive: fd == -1\n"));
                return False;
        }
        if (!send_keepalive(cli->fd)) {
                close(cli->fd);
                cli->fd = -1;
                DEBUG(0,("Error sending keepalive packet to client.\n"));
                return False;
        }
        return True;
}

/****************************************************************************
 Send/receive a SMBecho command: ping the server
****************************************************************************/

bool cli_echo(struct cli_state *cli, uint16 num_echos,
	      unsigned char *data, size_t length)
{
	char *p;
	int i;

	SMB_ASSERT(length < 1024);

	memset(cli->outbuf,'\0',smb_size);
	set_message(cli->outbuf,1,length,True);
	SCVAL(cli->outbuf,smb_com,SMBecho);
	SSVAL(cli->outbuf,smb_tid,65535);
	SSVAL(cli->outbuf,smb_vwv0,num_echos);
	cli_setup_packet(cli);
	p = smb_buf(cli->outbuf);
	memcpy(p, data, length);
	p += length;

	cli_setup_bcc(cli, p);

	cli_send_smb(cli);

	for (i=0; i<num_echos; i++) {
		if (!cli_receive_smb(cli)) {
			return False;
		}

		if (cli_is_error(cli)) {
			return False;
		}
	}

	return True;
}