xref: /openbmc/linux/fs/smb/client/sess.c (revision 36db6e8484ed455bbb320d89a119378897ae991c)
1  // SPDX-License-Identifier: LGPL-2.1
2  /*
3   *
4   *   SMB/CIFS session setup handling routines
5   *
6   *   Copyright (c) International Business Machines  Corp., 2006, 2009
7   *   Author(s): Steve French (sfrench@us.ibm.com)
8   *
9   */
10  
11  #include "cifspdu.h"
12  #include "cifsglob.h"
13  #include "cifsproto.h"
14  #include "cifs_unicode.h"
15  #include "cifs_debug.h"
16  #include "ntlmssp.h"
17  #include "nterr.h"
18  #include <linux/utsname.h>
19  #include <linux/slab.h>
20  #include <linux/version.h>
21  #include "cifsfs.h"
22  #include "cifs_spnego.h"
23  #include "smb2proto.h"
24  #include "fs_context.h"
25  
26  static int
27  cifs_ses_add_channel(struct cifs_ses *ses,
28  		     struct cifs_server_iface *iface);
29  
30  bool
is_server_using_iface(struct TCP_Server_Info * server,struct cifs_server_iface * iface)31  is_server_using_iface(struct TCP_Server_Info *server,
32  		      struct cifs_server_iface *iface)
33  {
34  	struct sockaddr_in *i4 = (struct sockaddr_in *)&iface->sockaddr;
35  	struct sockaddr_in6 *i6 = (struct sockaddr_in6 *)&iface->sockaddr;
36  	struct sockaddr_in *s4 = (struct sockaddr_in *)&server->dstaddr;
37  	struct sockaddr_in6 *s6 = (struct sockaddr_in6 *)&server->dstaddr;
38  
39  	if (server->dstaddr.ss_family != iface->sockaddr.ss_family)
40  		return false;
41  	if (server->dstaddr.ss_family == AF_INET) {
42  		if (s4->sin_addr.s_addr != i4->sin_addr.s_addr)
43  			return false;
44  	} else if (server->dstaddr.ss_family == AF_INET6) {
45  		if (memcmp(&s6->sin6_addr, &i6->sin6_addr,
46  			   sizeof(i6->sin6_addr)) != 0)
47  			return false;
48  	} else {
49  		/* unknown family.. */
50  		return false;
51  	}
52  	return true;
53  }
54  
is_ses_using_iface(struct cifs_ses * ses,struct cifs_server_iface * iface)55  bool is_ses_using_iface(struct cifs_ses *ses, struct cifs_server_iface *iface)
56  {
57  	int i;
58  
59  	spin_lock(&ses->chan_lock);
60  	for (i = 0; i < ses->chan_count; i++) {
61  		if (ses->chans[i].iface == iface) {
62  			spin_unlock(&ses->chan_lock);
63  			return true;
64  		}
65  	}
66  	spin_unlock(&ses->chan_lock);
67  	return false;
68  }
69  
70  /* channel helper functions. assumed that chan_lock is held by caller. */
71  
72  int
cifs_ses_get_chan_index(struct cifs_ses * ses,struct TCP_Server_Info * server)73  cifs_ses_get_chan_index(struct cifs_ses *ses,
74  			struct TCP_Server_Info *server)
75  {
76  	unsigned int i;
77  
78  	/* if the channel is waiting for termination */
79  	if (server && server->terminate)
80  		return CIFS_INVAL_CHAN_INDEX;
81  
82  	for (i = 0; i < ses->chan_count; i++) {
83  		if (ses->chans[i].server == server)
84  			return i;
85  	}
86  
87  	/* If we didn't find the channel, it is likely a bug */
88  	if (server)
89  		cifs_dbg(VFS, "unable to get chan index for server: 0x%llx",
90  			 server->conn_id);
91  	return CIFS_INVAL_CHAN_INDEX;
92  }
93  
94  void
cifs_chan_set_in_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)95  cifs_chan_set_in_reconnect(struct cifs_ses *ses,
96  			     struct TCP_Server_Info *server)
97  {
98  	int chan_index = cifs_ses_get_chan_index(ses, server);
99  
100  	if (chan_index == CIFS_INVAL_CHAN_INDEX)
101  		return;
102  
103  	ses->chans[chan_index].in_reconnect = true;
104  }
105  
106  void
cifs_chan_clear_in_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)107  cifs_chan_clear_in_reconnect(struct cifs_ses *ses,
108  			     struct TCP_Server_Info *server)
109  {
110  	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
111  
112  	if (chan_index == CIFS_INVAL_CHAN_INDEX)
113  		return;
114  
115  	ses->chans[chan_index].in_reconnect = false;
116  }
117  
118  bool
cifs_chan_in_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)119  cifs_chan_in_reconnect(struct cifs_ses *ses,
120  			  struct TCP_Server_Info *server)
121  {
122  	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
123  
124  	if (chan_index == CIFS_INVAL_CHAN_INDEX)
125  		return true;	/* err on the safer side */
126  
127  	return CIFS_CHAN_IN_RECONNECT(ses, chan_index);
128  }
129  
130  void
cifs_chan_set_need_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)131  cifs_chan_set_need_reconnect(struct cifs_ses *ses,
132  			     struct TCP_Server_Info *server)
133  {
134  	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
135  
136  	if (chan_index == CIFS_INVAL_CHAN_INDEX)
137  		return;
138  
139  	set_bit(chan_index, &ses->chans_need_reconnect);
140  	cifs_dbg(FYI, "Set reconnect bitmask for chan %u; now 0x%lx\n",
141  		 chan_index, ses->chans_need_reconnect);
142  }
143  
144  void
cifs_chan_clear_need_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)145  cifs_chan_clear_need_reconnect(struct cifs_ses *ses,
146  			       struct TCP_Server_Info *server)
147  {
148  	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
149  
150  	if (chan_index == CIFS_INVAL_CHAN_INDEX)
151  		return;
152  
153  	clear_bit(chan_index, &ses->chans_need_reconnect);
154  	cifs_dbg(FYI, "Cleared reconnect bitmask for chan %u; now 0x%lx\n",
155  		 chan_index, ses->chans_need_reconnect);
156  }
157  
158  bool
cifs_chan_needs_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)159  cifs_chan_needs_reconnect(struct cifs_ses *ses,
160  			  struct TCP_Server_Info *server)
161  {
162  	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
163  
164  	if (chan_index == CIFS_INVAL_CHAN_INDEX)
165  		return true;	/* err on the safer side */
166  
167  	return CIFS_CHAN_NEEDS_RECONNECT(ses, chan_index);
168  }
169  
170  bool
cifs_chan_is_iface_active(struct cifs_ses * ses,struct TCP_Server_Info * server)171  cifs_chan_is_iface_active(struct cifs_ses *ses,
172  			  struct TCP_Server_Info *server)
173  {
174  	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
175  
176  	if (chan_index == CIFS_INVAL_CHAN_INDEX)
177  		return true;	/* err on the safer side */
178  
179  	return ses->chans[chan_index].iface &&
180  		ses->chans[chan_index].iface->is_active;
181  }
182  
183  /* returns number of channels added */
cifs_try_adding_channels(struct cifs_ses * ses)184  int cifs_try_adding_channels(struct cifs_ses *ses)
185  {
186  	struct TCP_Server_Info *server = ses->server;
187  	int old_chan_count, new_chan_count;
188  	int left;
189  	int rc = 0;
190  	int tries = 0;
191  	size_t iface_weight = 0, iface_min_speed = 0;
192  	struct cifs_server_iface *iface = NULL, *niface = NULL;
193  	struct cifs_server_iface *last_iface = NULL;
194  
195  	spin_lock(&ses->chan_lock);
196  
197  	new_chan_count = old_chan_count = ses->chan_count;
198  	left = ses->chan_max - ses->chan_count;
199  
200  	if (left <= 0) {
201  		spin_unlock(&ses->chan_lock);
202  		cifs_dbg(FYI,
203  			 "ses already at max_channels (%zu), nothing to open\n",
204  			 ses->chan_max);
205  		return 0;
206  	}
207  
208  	if (server->dialect < SMB30_PROT_ID) {
209  		spin_unlock(&ses->chan_lock);
210  		cifs_dbg(VFS, "multichannel is not supported on this protocol version, use 3.0 or above\n");
211  		return 0;
212  	}
213  
214  	if (!(server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
215  		spin_unlock(&ses->chan_lock);
216  		cifs_server_dbg(VFS, "no multichannel support\n");
217  		return 0;
218  	}
219  	spin_unlock(&ses->chan_lock);
220  
221  	while (left > 0) {
222  
223  		tries++;
224  		if (tries > 3*ses->chan_max) {
225  			cifs_dbg(VFS, "too many channel open attempts (%d channels left to open)\n",
226  				 left);
227  			break;
228  		}
229  
230  		spin_lock(&ses->iface_lock);
231  		if (!ses->iface_count) {
232  			spin_unlock(&ses->iface_lock);
233  			cifs_dbg(ONCE, "server %s does not advertise interfaces\n",
234  				      ses->server->hostname);
235  			break;
236  		}
237  
238  		if (!iface)
239  			iface = list_first_entry(&ses->iface_list, struct cifs_server_iface,
240  						 iface_head);
241  		last_iface = list_last_entry(&ses->iface_list, struct cifs_server_iface,
242  					     iface_head);
243  		iface_min_speed = last_iface->speed;
244  
245  		list_for_each_entry_safe_from(iface, niface, &ses->iface_list,
246  				    iface_head) {
247  			/* do not mix rdma and non-rdma interfaces */
248  			if (iface->rdma_capable != ses->server->rdma)
249  				continue;
250  
251  			/* skip ifaces that are unusable */
252  			if (!iface->is_active ||
253  			    (is_ses_using_iface(ses, iface) &&
254  			     !iface->rss_capable))
255  				continue;
256  
257  			/* check if we already allocated enough channels */
258  			iface_weight = iface->speed / iface_min_speed;
259  
260  			if (iface->weight_fulfilled >= iface_weight)
261  				continue;
262  
263  			/* take ref before unlock */
264  			kref_get(&iface->refcount);
265  
266  			spin_unlock(&ses->iface_lock);
267  			rc = cifs_ses_add_channel(ses, iface);
268  			spin_lock(&ses->iface_lock);
269  
270  			if (rc) {
271  				cifs_dbg(VFS, "failed to open extra channel on iface:%pIS rc=%d\n",
272  					 &iface->sockaddr,
273  					 rc);
274  				kref_put(&iface->refcount, release_iface);
275  				/* failure to add chan should increase weight */
276  				iface->weight_fulfilled++;
277  				continue;
278  			}
279  
280  			iface->num_channels++;
281  			iface->weight_fulfilled++;
282  			cifs_dbg(VFS, "successfully opened new channel on iface:%pIS\n",
283  				 &iface->sockaddr);
284  			break;
285  		}
286  
287  		/* reached end of list. reset weight_fulfilled and start over */
288  		if (list_entry_is_head(iface, &ses->iface_list, iface_head)) {
289  			list_for_each_entry(iface, &ses->iface_list, iface_head)
290  				iface->weight_fulfilled = 0;
291  			spin_unlock(&ses->iface_lock);
292  			iface = NULL;
293  			continue;
294  		}
295  		spin_unlock(&ses->iface_lock);
296  
297  		left--;
298  		new_chan_count++;
299  	}
300  
301  	return new_chan_count - old_chan_count;
302  }
303  
304  /*
305   * called when multichannel is disabled by the server.
306   * this always gets called from smb2_reconnect
307   * and cannot get called in parallel threads.
308   */
309  void
cifs_disable_secondary_channels(struct cifs_ses * ses)310  cifs_disable_secondary_channels(struct cifs_ses *ses)
311  {
312  	int i, chan_count;
313  	struct TCP_Server_Info *server;
314  	struct cifs_server_iface *iface;
315  
316  	spin_lock(&ses->chan_lock);
317  	chan_count = ses->chan_count;
318  	if (chan_count == 1)
319  		goto done;
320  
321  	ses->chan_count = 1;
322  
323  	/* for all secondary channels reset the need reconnect bit */
324  	ses->chans_need_reconnect &= 1;
325  
326  	for (i = 1; i < chan_count; i++) {
327  		iface = ses->chans[i].iface;
328  		server = ses->chans[i].server;
329  
330  		/*
331  		 * remove these references first, since we need to unlock
332  		 * the chan_lock here, since iface_lock is a higher lock
333  		 */
334  		ses->chans[i].iface = NULL;
335  		ses->chans[i].server = NULL;
336  		spin_unlock(&ses->chan_lock);
337  
338  		if (iface) {
339  			spin_lock(&ses->iface_lock);
340  			iface->num_channels--;
341  			if (iface->weight_fulfilled)
342  				iface->weight_fulfilled--;
343  			kref_put(&iface->refcount, release_iface);
344  			spin_unlock(&ses->iface_lock);
345  		}
346  
347  		if (server) {
348  			if (!server->terminate) {
349  				server->terminate = true;
350  				cifs_signal_cifsd_for_reconnect(server, false);
351  			}
352  			cifs_put_tcp_session(server, false);
353  		}
354  
355  		spin_lock(&ses->chan_lock);
356  	}
357  
358  done:
359  	spin_unlock(&ses->chan_lock);
360  }
361  
362  /*
363   * update the iface for the channel if necessary.
364   * Must be called with chan_lock held.
365   */
366  void
cifs_chan_update_iface(struct cifs_ses * ses,struct TCP_Server_Info * server)367  cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
368  {
369  	unsigned int chan_index;
370  	size_t iface_weight = 0, iface_min_speed = 0;
371  	struct cifs_server_iface *iface = NULL;
372  	struct cifs_server_iface *old_iface = NULL;
373  	struct cifs_server_iface *last_iface = NULL;
374  	struct sockaddr_storage ss;
375  
376  	spin_lock(&ses->chan_lock);
377  	chan_index = cifs_ses_get_chan_index(ses, server);
378  	if (chan_index == CIFS_INVAL_CHAN_INDEX) {
379  		spin_unlock(&ses->chan_lock);
380  		return;
381  	}
382  
383  	if (ses->chans[chan_index].iface) {
384  		old_iface = ses->chans[chan_index].iface;
385  		if (old_iface->is_active) {
386  			spin_unlock(&ses->chan_lock);
387  			return;
388  		}
389  	}
390  	spin_unlock(&ses->chan_lock);
391  
392  	spin_lock(&server->srv_lock);
393  	ss = server->dstaddr;
394  	spin_unlock(&server->srv_lock);
395  
396  	spin_lock(&ses->iface_lock);
397  	if (!ses->iface_count) {
398  		spin_unlock(&ses->iface_lock);
399  		cifs_dbg(ONCE, "server %s does not advertise interfaces\n", ses->server->hostname);
400  		return;
401  	}
402  
403  	last_iface = list_last_entry(&ses->iface_list, struct cifs_server_iface,
404  				     iface_head);
405  	iface_min_speed = last_iface->speed;
406  
407  	/* then look for a new one */
408  	list_for_each_entry(iface, &ses->iface_list, iface_head) {
409  		if (!chan_index) {
410  			/* if we're trying to get the updated iface for primary channel */
411  			if (!cifs_match_ipaddr((struct sockaddr *) &ss,
412  					       (struct sockaddr *) &iface->sockaddr))
413  				continue;
414  
415  			kref_get(&iface->refcount);
416  			break;
417  		}
418  
419  		/* do not mix rdma and non-rdma interfaces */
420  		if (iface->rdma_capable != server->rdma)
421  			continue;
422  
423  		if (!iface->is_active ||
424  		    (is_ses_using_iface(ses, iface) &&
425  		     !iface->rss_capable)) {
426  			continue;
427  		}
428  
429  		/* check if we already allocated enough channels */
430  		iface_weight = iface->speed / iface_min_speed;
431  
432  		if (iface->weight_fulfilled >= iface_weight)
433  			continue;
434  
435  		kref_get(&iface->refcount);
436  		break;
437  	}
438  
439  	if (list_entry_is_head(iface, &ses->iface_list, iface_head)) {
440  		iface = NULL;
441  		cifs_dbg(FYI, "unable to find a suitable iface\n");
442  	}
443  
444  	if (!iface) {
445  		if (!chan_index)
446  			cifs_dbg(FYI, "unable to get the interface matching: %pIS\n",
447  				 &ss);
448  		else {
449  			cifs_dbg(FYI, "unable to find another interface to replace: %pIS\n",
450  				 &old_iface->sockaddr);
451  		}
452  
453  		spin_unlock(&ses->iface_lock);
454  		return;
455  	}
456  
457  	/* now drop the ref to the current iface */
458  	if (old_iface) {
459  		cifs_dbg(FYI, "replacing iface: %pIS with %pIS\n",
460  			 &old_iface->sockaddr,
461  			 &iface->sockaddr);
462  
463  		old_iface->num_channels--;
464  		if (old_iface->weight_fulfilled)
465  			old_iface->weight_fulfilled--;
466  		iface->num_channels++;
467  		iface->weight_fulfilled++;
468  
469  		kref_put(&old_iface->refcount, release_iface);
470  	} else if (!chan_index) {
471  		/* special case: update interface for primary channel */
472  		cifs_dbg(FYI, "referencing primary channel iface: %pIS\n",
473  			 &iface->sockaddr);
474  		iface->num_channels++;
475  		iface->weight_fulfilled++;
476  	}
477  	spin_unlock(&ses->iface_lock);
478  
479  	spin_lock(&ses->chan_lock);
480  	chan_index = cifs_ses_get_chan_index(ses, server);
481  	if (chan_index == CIFS_INVAL_CHAN_INDEX) {
482  		spin_unlock(&ses->chan_lock);
483  		return;
484  	}
485  
486  	ses->chans[chan_index].iface = iface;
487  	spin_unlock(&ses->chan_lock);
488  }
489  
490  /*
491   * If server is a channel of ses, return the corresponding enclosing
492   * cifs_chan otherwise return NULL.
493   */
494  struct cifs_chan *
cifs_ses_find_chan(struct cifs_ses * ses,struct TCP_Server_Info * server)495  cifs_ses_find_chan(struct cifs_ses *ses, struct TCP_Server_Info *server)
496  {
497  	int i;
498  
499  	spin_lock(&ses->chan_lock);
500  	for (i = 0; i < ses->chan_count; i++) {
501  		if (ses->chans[i].server == server) {
502  			spin_unlock(&ses->chan_lock);
503  			return &ses->chans[i];
504  		}
505  	}
506  	spin_unlock(&ses->chan_lock);
507  	return NULL;
508  }
509  
510  static int
cifs_ses_add_channel(struct cifs_ses * ses,struct cifs_server_iface * iface)511  cifs_ses_add_channel(struct cifs_ses *ses,
512  		     struct cifs_server_iface *iface)
513  {
514  	struct TCP_Server_Info *chan_server;
515  	struct cifs_chan *chan;
516  	struct smb3_fs_context *ctx;
517  	static const char unc_fmt[] = "\\%s\\foo";
518  	struct sockaddr_in *ipv4 = (struct sockaddr_in *)&iface->sockaddr;
519  	struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&iface->sockaddr;
520  	size_t len;
521  	int rc;
522  	unsigned int xid = get_xid();
523  
524  	if (iface->sockaddr.ss_family == AF_INET)
525  		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI4)\n",
526  			 ses, iface->speed, iface->rdma_capable ? "yes" : "no",
527  			 &ipv4->sin_addr);
528  	else
529  		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI6)\n",
530  			 ses, iface->speed, iface->rdma_capable ? "yes" : "no",
531  			 &ipv6->sin6_addr);
532  
533  	/*
534  	 * Setup a ctx with mostly the same info as the existing
535  	 * session and overwrite it with the requested iface data.
536  	 *
537  	 * We need to setup at least the fields used for negprot and
538  	 * sesssetup.
539  	 *
540  	 * We only need the ctx here, so we can reuse memory from
541  	 * the session and server without caring about memory
542  	 * management.
543  	 */
544  	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
545  	if (!ctx) {
546  		rc = -ENOMEM;
547  		goto out_free_xid;
548  	}
549  
550  	/* Always make new connection for now (TODO?) */
551  	ctx->nosharesock = true;
552  
553  	/* Auth */
554  	ctx->domainauto = ses->domainAuto;
555  	ctx->domainname = ses->domainName;
556  
557  	/* no hostname for extra channels */
558  	ctx->server_hostname = "";
559  
560  	ctx->username = ses->user_name;
561  	ctx->password = ses->password;
562  	ctx->sectype = ses->sectype;
563  	ctx->sign = ses->sign;
564  
565  	/* UNC and paths */
566  	/* XXX: Use ses->server->hostname? */
567  	len = sizeof(unc_fmt) + SERVER_NAME_LEN_WITH_NULL;
568  	ctx->UNC = kzalloc(len, GFP_KERNEL);
569  	if (!ctx->UNC) {
570  		rc = -ENOMEM;
571  		goto out_free_ctx;
572  	}
573  	scnprintf(ctx->UNC, len, unc_fmt, ses->ip_addr);
574  	ctx->prepath = "";
575  
576  	/* Reuse same version as master connection */
577  	ctx->vals = ses->server->vals;
578  	ctx->ops = ses->server->ops;
579  
580  	ctx->noblocksnd = ses->server->noblocksnd;
581  	ctx->noautotune = ses->server->noautotune;
582  	ctx->sockopt_tcp_nodelay = ses->server->tcp_nodelay;
583  	ctx->echo_interval = ses->server->echo_interval / HZ;
584  	ctx->max_credits = ses->server->max_credits;
585  
586  	/*
587  	 * This will be used for encoding/decoding user/domain/pw
588  	 * during sess setup auth.
589  	 */
590  	ctx->local_nls = ses->local_nls;
591  
592  	/* Use RDMA if possible */
593  	ctx->rdma = iface->rdma_capable;
594  	memcpy(&ctx->dstaddr, &iface->sockaddr, sizeof(ctx->dstaddr));
595  
596  	/* reuse master con client guid */
597  	memcpy(&ctx->client_guid, ses->server->client_guid,
598  	       sizeof(ctx->client_guid));
599  	ctx->use_client_guid = true;
600  
601  	chan_server = cifs_get_tcp_session(ctx, ses->server);
602  
603  	spin_lock(&ses->chan_lock);
604  	chan = &ses->chans[ses->chan_count];
605  	chan->server = chan_server;
606  	if (IS_ERR(chan->server)) {
607  		rc = PTR_ERR(chan->server);
608  		chan->server = NULL;
609  		spin_unlock(&ses->chan_lock);
610  		goto out;
611  	}
612  	chan->iface = iface;
613  	ses->chan_count++;
614  	atomic_set(&ses->chan_seq, 0);
615  
616  	/* Mark this channel as needing connect/setup */
617  	cifs_chan_set_need_reconnect(ses, chan->server);
618  
619  	spin_unlock(&ses->chan_lock);
620  
621  	mutex_lock(&ses->session_mutex);
622  	/*
623  	 * We need to allocate the server crypto now as we will need
624  	 * to sign packets before we generate the channel signing key
625  	 * (we sign with the session key)
626  	 */
627  	rc = smb311_crypto_shash_allocate(chan->server);
628  	if (rc) {
629  		cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
630  		mutex_unlock(&ses->session_mutex);
631  		goto out;
632  	}
633  
634  	rc = cifs_negotiate_protocol(xid, ses, chan->server);
635  	if (!rc)
636  		rc = cifs_setup_session(xid, ses, chan->server, ses->local_nls);
637  
638  	mutex_unlock(&ses->session_mutex);
639  
640  out:
641  	if (rc && chan->server) {
642  		cifs_put_tcp_session(chan->server, 0);
643  
644  		spin_lock(&ses->chan_lock);
645  
646  		/* we rely on all bits beyond chan_count to be clear */
647  		cifs_chan_clear_need_reconnect(ses, chan->server);
648  		ses->chan_count--;
649  		/*
650  		 * chan_count should never reach 0 as at least the primary
651  		 * channel is always allocated
652  		 */
653  		WARN_ON(ses->chan_count < 1);
654  		spin_unlock(&ses->chan_lock);
655  	}
656  
657  	kfree(ctx->UNC);
658  out_free_ctx:
659  	kfree(ctx);
660  out_free_xid:
661  	free_xid(xid);
662  	return rc;
663  }
664  
665  #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
cifs_ssetup_hdr(struct cifs_ses * ses,struct TCP_Server_Info * server,SESSION_SETUP_ANDX * pSMB)666  static __u32 cifs_ssetup_hdr(struct cifs_ses *ses,
667  			     struct TCP_Server_Info *server,
668  			     SESSION_SETUP_ANDX *pSMB)
669  {
670  	__u32 capabilities = 0;
671  
672  	/* init fields common to all four types of SessSetup */
673  	/* Note that offsets for first seven fields in req struct are same  */
674  	/*	in CIFS Specs so does not matter which of 3 forms of struct */
675  	/*	that we use in next few lines                               */
676  	/* Note that header is initialized to zero in header_assemble */
677  	pSMB->req.AndXCommand = 0xFF;
678  	pSMB->req.MaxBufferSize = cpu_to_le16(min_t(u32,
679  					CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4,
680  					USHRT_MAX));
681  	pSMB->req.MaxMpxCount = cpu_to_le16(server->maxReq);
682  	pSMB->req.VcNumber = cpu_to_le16(1);
683  
684  	/* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
685  
686  	/* BB verify whether signing required on neg or just auth frame (and NTLM case) */
687  
688  	capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
689  			CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
690  
691  	if (server->sign)
692  		pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
693  
694  	if (ses->capabilities & CAP_UNICODE) {
695  		pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
696  		capabilities |= CAP_UNICODE;
697  	}
698  	if (ses->capabilities & CAP_STATUS32) {
699  		pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
700  		capabilities |= CAP_STATUS32;
701  	}
702  	if (ses->capabilities & CAP_DFS) {
703  		pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
704  		capabilities |= CAP_DFS;
705  	}
706  	if (ses->capabilities & CAP_UNIX)
707  		capabilities |= CAP_UNIX;
708  
709  	return capabilities;
710  }
711  
712  static void
unicode_oslm_strings(char ** pbcc_area,const struct nls_table * nls_cp)713  unicode_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
714  {
715  	char *bcc_ptr = *pbcc_area;
716  	int bytes_ret = 0;
717  
718  	/* Copy OS version */
719  	bytes_ret = cifs_strtoUTF16((__le16 *)bcc_ptr, "Linux version ", 32,
720  				    nls_cp);
721  	bcc_ptr += 2 * bytes_ret;
722  	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, init_utsname()->release,
723  				    32, nls_cp);
724  	bcc_ptr += 2 * bytes_ret;
725  	bcc_ptr += 2; /* trailing null */
726  
727  	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
728  				    32, nls_cp);
729  	bcc_ptr += 2 * bytes_ret;
730  	bcc_ptr += 2; /* trailing null */
731  
732  	*pbcc_area = bcc_ptr;
733  }
734  
unicode_domain_string(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)735  static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
736  				   const struct nls_table *nls_cp)
737  {
738  	char *bcc_ptr = *pbcc_area;
739  	int bytes_ret = 0;
740  
741  	/* copy domain */
742  	if (ses->domainName == NULL) {
743  		/*
744  		 * Sending null domain better than using a bogus domain name (as
745  		 * we did briefly in 2.6.18) since server will use its default
746  		 */
747  		*bcc_ptr = 0;
748  		*(bcc_ptr+1) = 0;
749  		bytes_ret = 0;
750  	} else
751  		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
752  					    CIFS_MAX_DOMAINNAME_LEN, nls_cp);
753  	bcc_ptr += 2 * bytes_ret;
754  	bcc_ptr += 2;  /* account for null terminator */
755  
756  	*pbcc_area = bcc_ptr;
757  }
758  
unicode_ssetup_strings(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)759  static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
760  				   const struct nls_table *nls_cp)
761  {
762  	char *bcc_ptr = *pbcc_area;
763  	int bytes_ret = 0;
764  
765  	/* BB FIXME add check that strings less than 335 or will need to send as arrays */
766  
767  	/* copy user */
768  	if (ses->user_name == NULL) {
769  		/* null user mount */
770  		*bcc_ptr = 0;
771  		*(bcc_ptr+1) = 0;
772  	} else {
773  		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->user_name,
774  					    CIFS_MAX_USERNAME_LEN, nls_cp);
775  	}
776  	bcc_ptr += 2 * bytes_ret;
777  	bcc_ptr += 2; /* account for null termination */
778  
779  	unicode_domain_string(&bcc_ptr, ses, nls_cp);
780  	unicode_oslm_strings(&bcc_ptr, nls_cp);
781  
782  	*pbcc_area = bcc_ptr;
783  }
784  
ascii_ssetup_strings(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)785  static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
786  				 const struct nls_table *nls_cp)
787  {
788  	char *bcc_ptr = *pbcc_area;
789  	int len;
790  
791  	/* copy user */
792  	/* BB what about null user mounts - check that we do this BB */
793  	/* copy user */
794  	if (ses->user_name != NULL) {
795  		len = strscpy(bcc_ptr, ses->user_name, CIFS_MAX_USERNAME_LEN);
796  		if (WARN_ON_ONCE(len < 0))
797  			len = CIFS_MAX_USERNAME_LEN - 1;
798  		bcc_ptr += len;
799  	}
800  	/* else null user mount */
801  	*bcc_ptr = 0;
802  	bcc_ptr++; /* account for null termination */
803  
804  	/* copy domain */
805  	if (ses->domainName != NULL) {
806  		len = strscpy(bcc_ptr, ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
807  		if (WARN_ON_ONCE(len < 0))
808  			len = CIFS_MAX_DOMAINNAME_LEN - 1;
809  		bcc_ptr += len;
810  	} /* else we send a null domain name so server will default to its own domain */
811  	*bcc_ptr = 0;
812  	bcc_ptr++;
813  
814  	/* BB check for overflow here */
815  
816  	strcpy(bcc_ptr, "Linux version ");
817  	bcc_ptr += strlen("Linux version ");
818  	strcpy(bcc_ptr, init_utsname()->release);
819  	bcc_ptr += strlen(init_utsname()->release) + 1;
820  
821  	strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
822  	bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;
823  
824  	*pbcc_area = bcc_ptr;
825  }
826  
827  static void
decode_unicode_ssetup(char ** pbcc_area,int bleft,struct cifs_ses * ses,const struct nls_table * nls_cp)828  decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifs_ses *ses,
829  		      const struct nls_table *nls_cp)
830  {
831  	int len;
832  	char *data = *pbcc_area;
833  
834  	cifs_dbg(FYI, "bleft %d\n", bleft);
835  
836  	kfree(ses->serverOS);
837  	ses->serverOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
838  	cifs_dbg(FYI, "serverOS=%s\n", ses->serverOS);
839  	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
840  	data += len;
841  	bleft -= len;
842  	if (bleft <= 0)
843  		return;
844  
845  	kfree(ses->serverNOS);
846  	ses->serverNOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
847  	cifs_dbg(FYI, "serverNOS=%s\n", ses->serverNOS);
848  	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
849  	data += len;
850  	bleft -= len;
851  	if (bleft <= 0)
852  		return;
853  
854  	kfree(ses->serverDomain);
855  	ses->serverDomain = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
856  	cifs_dbg(FYI, "serverDomain=%s\n", ses->serverDomain);
857  
858  	return;
859  }
860  
decode_ascii_ssetup(char ** pbcc_area,__u16 bleft,struct cifs_ses * ses,const struct nls_table * nls_cp)861  static void decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
862  				struct cifs_ses *ses,
863  				const struct nls_table *nls_cp)
864  {
865  	int len;
866  	char *bcc_ptr = *pbcc_area;
867  
868  	cifs_dbg(FYI, "decode sessetup ascii. bleft %d\n", bleft);
869  
870  	len = strnlen(bcc_ptr, bleft);
871  	if (len >= bleft)
872  		return;
873  
874  	kfree(ses->serverOS);
875  
876  	ses->serverOS = kmalloc(len + 1, GFP_KERNEL);
877  	if (ses->serverOS) {
878  		memcpy(ses->serverOS, bcc_ptr, len);
879  		ses->serverOS[len] = 0;
880  		if (strncmp(ses->serverOS, "OS/2", 4) == 0)
881  			cifs_dbg(FYI, "OS/2 server\n");
882  	}
883  
884  	bcc_ptr += len + 1;
885  	bleft -= len + 1;
886  
887  	len = strnlen(bcc_ptr, bleft);
888  	if (len >= bleft)
889  		return;
890  
891  	kfree(ses->serverNOS);
892  
893  	ses->serverNOS = kmalloc(len + 1, GFP_KERNEL);
894  	if (ses->serverNOS) {
895  		memcpy(ses->serverNOS, bcc_ptr, len);
896  		ses->serverNOS[len] = 0;
897  	}
898  
899  	bcc_ptr += len + 1;
900  	bleft -= len + 1;
901  
902  	len = strnlen(bcc_ptr, bleft);
903  	if (len > bleft)
904  		return;
905  
906  	/*
907  	 * No domain field in LANMAN case. Domain is
908  	 * returned by old servers in the SMB negprot response
909  	 *
910  	 * BB For newer servers which do not support Unicode,
911  	 * but thus do return domain here, we could add parsing
912  	 * for it later, but it is not very important
913  	 */
914  	cifs_dbg(FYI, "ascii: bytes left %d\n", bleft);
915  }
916  #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
917  
decode_ntlmssp_challenge(char * bcc_ptr,int blob_len,struct cifs_ses * ses)918  int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
919  				    struct cifs_ses *ses)
920  {
921  	unsigned int tioffset; /* challenge message target info area */
922  	unsigned int tilen; /* challenge message target info area length  */
923  	CHALLENGE_MESSAGE *pblob = (CHALLENGE_MESSAGE *)bcc_ptr;
924  	__u32 server_flags;
925  
926  	if (blob_len < sizeof(CHALLENGE_MESSAGE)) {
927  		cifs_dbg(VFS, "challenge blob len %d too small\n", blob_len);
928  		return -EINVAL;
929  	}
930  
931  	if (memcmp(pblob->Signature, "NTLMSSP", 8)) {
932  		cifs_dbg(VFS, "blob signature incorrect %s\n",
933  			 pblob->Signature);
934  		return -EINVAL;
935  	}
936  	if (pblob->MessageType != NtLmChallenge) {
937  		cifs_dbg(VFS, "Incorrect message type %d\n",
938  			 pblob->MessageType);
939  		return -EINVAL;
940  	}
941  
942  	server_flags = le32_to_cpu(pblob->NegotiateFlags);
943  	cifs_dbg(FYI, "%s: negotiate=0x%08x challenge=0x%08x\n", __func__,
944  		 ses->ntlmssp->client_flags, server_flags);
945  
946  	if ((ses->ntlmssp->client_flags & (NTLMSSP_NEGOTIATE_SEAL | NTLMSSP_NEGOTIATE_SIGN)) &&
947  	    (!(server_flags & NTLMSSP_NEGOTIATE_56) && !(server_flags & NTLMSSP_NEGOTIATE_128))) {
948  		cifs_dbg(VFS, "%s: requested signing/encryption but server did not return either 56-bit or 128-bit session key size\n",
949  			 __func__);
950  		return -EINVAL;
951  	}
952  	if (!(server_flags & NTLMSSP_NEGOTIATE_NTLM) && !(server_flags & NTLMSSP_NEGOTIATE_EXTENDED_SEC)) {
953  		cifs_dbg(VFS, "%s: server does not seem to support either NTLMv1 or NTLMv2\n", __func__);
954  		return -EINVAL;
955  	}
956  	if (ses->server->sign && !(server_flags & NTLMSSP_NEGOTIATE_SIGN)) {
957  		cifs_dbg(VFS, "%s: forced packet signing but server does not seem to support it\n",
958  			 __func__);
959  		return -EOPNOTSUPP;
960  	}
961  	if ((ses->ntlmssp->client_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
962  	    !(server_flags & NTLMSSP_NEGOTIATE_KEY_XCH))
963  		pr_warn_once("%s: authentication has been weakened as server does not support key exchange\n",
964  			     __func__);
965  
966  	ses->ntlmssp->server_flags = server_flags;
967  
968  	memcpy(ses->ntlmssp->cryptkey, pblob->Challenge, CIFS_CRYPTO_KEY_SIZE);
969  	/*
970  	 * In particular we can examine sign flags
971  	 *
972  	 * BB spec says that if AvId field of MsvAvTimestamp is populated then
973  	 * we must set the MIC field of the AUTHENTICATE_MESSAGE
974  	 */
975  
976  	tioffset = le32_to_cpu(pblob->TargetInfoArray.BufferOffset);
977  	tilen = le16_to_cpu(pblob->TargetInfoArray.Length);
978  	if (tioffset > blob_len || tioffset + tilen > blob_len) {
979  		cifs_dbg(VFS, "tioffset + tilen too high %u + %u\n",
980  			 tioffset, tilen);
981  		return -EINVAL;
982  	}
983  	if (tilen) {
984  		kfree_sensitive(ses->auth_key.response);
985  		ses->auth_key.response = kmemdup(bcc_ptr + tioffset, tilen,
986  						 GFP_KERNEL);
987  		if (!ses->auth_key.response) {
988  			cifs_dbg(VFS, "Challenge target info alloc failure\n");
989  			return -ENOMEM;
990  		}
991  		ses->auth_key.len = tilen;
992  	}
993  
994  	return 0;
995  }
996  
size_of_ntlmssp_blob(struct cifs_ses * ses,int base_size)997  static int size_of_ntlmssp_blob(struct cifs_ses *ses, int base_size)
998  {
999  	int sz = base_size + ses->auth_key.len
1000  		- CIFS_SESS_KEY_SIZE + CIFS_CPHTXT_SIZE + 2;
1001  
1002  	if (ses->domainName)
1003  		sz += sizeof(__le16) * strnlen(ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
1004  	else
1005  		sz += sizeof(__le16);
1006  
1007  	if (ses->user_name)
1008  		sz += sizeof(__le16) * strnlen(ses->user_name, CIFS_MAX_USERNAME_LEN);
1009  	else
1010  		sz += sizeof(__le16);
1011  
1012  	if (ses->workstation_name[0])
1013  		sz += sizeof(__le16) * strnlen(ses->workstation_name,
1014  					       ntlmssp_workstation_name_size(ses));
1015  	else
1016  		sz += sizeof(__le16);
1017  
1018  	return sz;
1019  }
1020  
cifs_security_buffer_from_str(SECURITY_BUFFER * pbuf,char * str_value,int str_length,unsigned char * pstart,unsigned char ** pcur,const struct nls_table * nls_cp)1021  static inline void cifs_security_buffer_from_str(SECURITY_BUFFER *pbuf,
1022  						 char *str_value,
1023  						 int str_length,
1024  						 unsigned char *pstart,
1025  						 unsigned char **pcur,
1026  						 const struct nls_table *nls_cp)
1027  {
1028  	unsigned char *tmp = pstart;
1029  	int len;
1030  
1031  	if (!pbuf)
1032  		return;
1033  
1034  	if (!pcur)
1035  		pcur = &tmp;
1036  
1037  	if (!str_value) {
1038  		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
1039  		pbuf->Length = 0;
1040  		pbuf->MaximumLength = 0;
1041  		*pcur += sizeof(__le16);
1042  	} else {
1043  		len = cifs_strtoUTF16((__le16 *)*pcur,
1044  				      str_value,
1045  				      str_length,
1046  				      nls_cp);
1047  		len *= sizeof(__le16);
1048  		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
1049  		pbuf->Length = cpu_to_le16(len);
1050  		pbuf->MaximumLength = cpu_to_le16(len);
1051  		*pcur += len;
1052  	}
1053  }
1054  
1055  /* BB Move to ntlmssp.c eventually */
1056  
build_ntlmssp_negotiate_blob(unsigned char ** pbuffer,u16 * buflen,struct cifs_ses * ses,struct TCP_Server_Info * server,const struct nls_table * nls_cp)1057  int build_ntlmssp_negotiate_blob(unsigned char **pbuffer,
1058  				 u16 *buflen,
1059  				 struct cifs_ses *ses,
1060  				 struct TCP_Server_Info *server,
1061  				 const struct nls_table *nls_cp)
1062  {
1063  	int rc = 0;
1064  	NEGOTIATE_MESSAGE *sec_blob;
1065  	__u32 flags;
1066  	unsigned char *tmp;
1067  	int len;
1068  
1069  	len = size_of_ntlmssp_blob(ses, sizeof(NEGOTIATE_MESSAGE));
1070  	*pbuffer = kmalloc(len, GFP_KERNEL);
1071  	if (!*pbuffer) {
1072  		rc = -ENOMEM;
1073  		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1074  		*buflen = 0;
1075  		goto setup_ntlm_neg_ret;
1076  	}
1077  	sec_blob = (NEGOTIATE_MESSAGE *)*pbuffer;
1078  
1079  	memset(*pbuffer, 0, sizeof(NEGOTIATE_MESSAGE));
1080  	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1081  	sec_blob->MessageType = NtLmNegotiate;
1082  
1083  	/* BB is NTLMV2 session security format easier to use here? */
1084  	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
1085  		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
1086  		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
1087  		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
1088  		NTLMSSP_NEGOTIATE_SIGN;
1089  	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
1090  		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
1091  
1092  	tmp = *pbuffer + sizeof(NEGOTIATE_MESSAGE);
1093  	ses->ntlmssp->client_flags = flags;
1094  	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1095  
1096  	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
1097  	cifs_security_buffer_from_str(&sec_blob->DomainName,
1098  				      NULL,
1099  				      CIFS_MAX_DOMAINNAME_LEN,
1100  				      *pbuffer, &tmp,
1101  				      nls_cp);
1102  
1103  	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1104  				      NULL,
1105  				      CIFS_MAX_WORKSTATION_LEN,
1106  				      *pbuffer, &tmp,
1107  				      nls_cp);
1108  
1109  	*buflen = tmp - *pbuffer;
1110  setup_ntlm_neg_ret:
1111  	return rc;
1112  }
1113  
1114  /*
1115   * Build ntlmssp blob with additional fields, such as version,
1116   * supported by modern servers. For safety limit to SMB3 or later
1117   * See notes in MS-NLMP Section 2.2.2.1 e.g.
1118   */
build_ntlmssp_smb3_negotiate_blob(unsigned char ** pbuffer,u16 * buflen,struct cifs_ses * ses,struct TCP_Server_Info * server,const struct nls_table * nls_cp)1119  int build_ntlmssp_smb3_negotiate_blob(unsigned char **pbuffer,
1120  				 u16 *buflen,
1121  				 struct cifs_ses *ses,
1122  				 struct TCP_Server_Info *server,
1123  				 const struct nls_table *nls_cp)
1124  {
1125  	int rc = 0;
1126  	struct negotiate_message *sec_blob;
1127  	__u32 flags;
1128  	unsigned char *tmp;
1129  	int len;
1130  
1131  	len = size_of_ntlmssp_blob(ses, sizeof(struct negotiate_message));
1132  	*pbuffer = kmalloc(len, GFP_KERNEL);
1133  	if (!*pbuffer) {
1134  		rc = -ENOMEM;
1135  		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1136  		*buflen = 0;
1137  		goto setup_ntlm_smb3_neg_ret;
1138  	}
1139  	sec_blob = (struct negotiate_message *)*pbuffer;
1140  
1141  	memset(*pbuffer, 0, sizeof(struct negotiate_message));
1142  	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1143  	sec_blob->MessageType = NtLmNegotiate;
1144  
1145  	/* BB is NTLMV2 session security format easier to use here? */
1146  	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
1147  		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
1148  		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
1149  		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
1150  		NTLMSSP_NEGOTIATE_SIGN | NTLMSSP_NEGOTIATE_VERSION;
1151  	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
1152  		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
1153  
1154  	sec_blob->Version.ProductMajorVersion = LINUX_VERSION_MAJOR;
1155  	sec_blob->Version.ProductMinorVersion = LINUX_VERSION_PATCHLEVEL;
1156  	sec_blob->Version.ProductBuild = cpu_to_le16(SMB3_PRODUCT_BUILD);
1157  	sec_blob->Version.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
1158  
1159  	tmp = *pbuffer + sizeof(struct negotiate_message);
1160  	ses->ntlmssp->client_flags = flags;
1161  	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1162  
1163  	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
1164  	cifs_security_buffer_from_str(&sec_blob->DomainName,
1165  				      NULL,
1166  				      CIFS_MAX_DOMAINNAME_LEN,
1167  				      *pbuffer, &tmp,
1168  				      nls_cp);
1169  
1170  	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1171  				      NULL,
1172  				      CIFS_MAX_WORKSTATION_LEN,
1173  				      *pbuffer, &tmp,
1174  				      nls_cp);
1175  
1176  	*buflen = tmp - *pbuffer;
1177  setup_ntlm_smb3_neg_ret:
1178  	return rc;
1179  }
1180  
1181  
1182  /* See MS-NLMP 2.2.1.3 */
build_ntlmssp_auth_blob(unsigned char ** pbuffer,u16 * buflen,struct cifs_ses * ses,struct TCP_Server_Info * server,const struct nls_table * nls_cp)1183  int build_ntlmssp_auth_blob(unsigned char **pbuffer,
1184  					u16 *buflen,
1185  				   struct cifs_ses *ses,
1186  				   struct TCP_Server_Info *server,
1187  				   const struct nls_table *nls_cp)
1188  {
1189  	int rc;
1190  	AUTHENTICATE_MESSAGE *sec_blob;
1191  	__u32 flags;
1192  	unsigned char *tmp;
1193  	int len;
1194  
1195  	rc = setup_ntlmv2_rsp(ses, nls_cp);
1196  	if (rc) {
1197  		cifs_dbg(VFS, "Error %d during NTLMSSP authentication\n", rc);
1198  		*buflen = 0;
1199  		goto setup_ntlmv2_ret;
1200  	}
1201  
1202  	len = size_of_ntlmssp_blob(ses, sizeof(AUTHENTICATE_MESSAGE));
1203  	*pbuffer = kmalloc(len, GFP_KERNEL);
1204  	if (!*pbuffer) {
1205  		rc = -ENOMEM;
1206  		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1207  		*buflen = 0;
1208  		goto setup_ntlmv2_ret;
1209  	}
1210  	sec_blob = (AUTHENTICATE_MESSAGE *)*pbuffer;
1211  
1212  	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1213  	sec_blob->MessageType = NtLmAuthenticate;
1214  
1215  	/* send version information in ntlmssp authenticate also */
1216  	flags = ses->ntlmssp->server_flags | NTLMSSP_REQUEST_TARGET |
1217  		NTLMSSP_NEGOTIATE_TARGET_INFO | NTLMSSP_NEGOTIATE_VERSION |
1218  		NTLMSSP_NEGOTIATE_WORKSTATION_SUPPLIED;
1219  
1220  	sec_blob->Version.ProductMajorVersion = LINUX_VERSION_MAJOR;
1221  	sec_blob->Version.ProductMinorVersion = LINUX_VERSION_PATCHLEVEL;
1222  	sec_blob->Version.ProductBuild = cpu_to_le16(SMB3_PRODUCT_BUILD);
1223  	sec_blob->Version.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
1224  
1225  	tmp = *pbuffer + sizeof(AUTHENTICATE_MESSAGE);
1226  	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1227  
1228  	sec_blob->LmChallengeResponse.BufferOffset =
1229  				cpu_to_le32(sizeof(AUTHENTICATE_MESSAGE));
1230  	sec_blob->LmChallengeResponse.Length = 0;
1231  	sec_blob->LmChallengeResponse.MaximumLength = 0;
1232  
1233  	sec_blob->NtChallengeResponse.BufferOffset =
1234  				cpu_to_le32(tmp - *pbuffer);
1235  	if (ses->user_name != NULL) {
1236  		memcpy(tmp, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
1237  				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1238  		tmp += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
1239  
1240  		sec_blob->NtChallengeResponse.Length =
1241  				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1242  		sec_blob->NtChallengeResponse.MaximumLength =
1243  				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1244  	} else {
1245  		/*
1246  		 * don't send an NT Response for anonymous access
1247  		 */
1248  		sec_blob->NtChallengeResponse.Length = 0;
1249  		sec_blob->NtChallengeResponse.MaximumLength = 0;
1250  	}
1251  
1252  	cifs_security_buffer_from_str(&sec_blob->DomainName,
1253  				      ses->domainName,
1254  				      CIFS_MAX_DOMAINNAME_LEN,
1255  				      *pbuffer, &tmp,
1256  				      nls_cp);
1257  
1258  	cifs_security_buffer_from_str(&sec_blob->UserName,
1259  				      ses->user_name,
1260  				      CIFS_MAX_USERNAME_LEN,
1261  				      *pbuffer, &tmp,
1262  				      nls_cp);
1263  
1264  	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1265  				      ses->workstation_name,
1266  				      ntlmssp_workstation_name_size(ses),
1267  				      *pbuffer, &tmp,
1268  				      nls_cp);
1269  
1270  	if ((ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
1271  	    (!ses->server->session_estab || ses->ntlmssp->sesskey_per_smbsess) &&
1272  	    !calc_seckey(ses)) {
1273  		memcpy(tmp, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
1274  		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
1275  		sec_blob->SessionKey.Length = cpu_to_le16(CIFS_CPHTXT_SIZE);
1276  		sec_blob->SessionKey.MaximumLength =
1277  				cpu_to_le16(CIFS_CPHTXT_SIZE);
1278  		tmp += CIFS_CPHTXT_SIZE;
1279  	} else {
1280  		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
1281  		sec_blob->SessionKey.Length = 0;
1282  		sec_blob->SessionKey.MaximumLength = 0;
1283  	}
1284  
1285  	*buflen = tmp - *pbuffer;
1286  setup_ntlmv2_ret:
1287  	return rc;
1288  }
1289  
1290  enum securityEnum
cifs_select_sectype(struct TCP_Server_Info * server,enum securityEnum requested)1291  cifs_select_sectype(struct TCP_Server_Info *server, enum securityEnum requested)
1292  {
1293  	switch (server->negflavor) {
1294  	case CIFS_NEGFLAVOR_EXTENDED:
1295  		switch (requested) {
1296  		case Kerberos:
1297  		case RawNTLMSSP:
1298  		case IAKerb:
1299  			return requested;
1300  		case Unspecified:
1301  			if (server->sec_ntlmssp &&
1302  			    (global_secflags & CIFSSEC_MAY_NTLMSSP))
1303  				return RawNTLMSSP;
1304  			if ((server->sec_kerberos || server->sec_mskerberos || server->sec_iakerb) &&
1305  			    (global_secflags & CIFSSEC_MAY_KRB5))
1306  				return Kerberos;
1307  			fallthrough;
1308  		default:
1309  			return Unspecified;
1310  		}
1311  	case CIFS_NEGFLAVOR_UNENCAP:
1312  		switch (requested) {
1313  		case NTLMv2:
1314  			return requested;
1315  		case Unspecified:
1316  			if (global_secflags & CIFSSEC_MAY_NTLMV2)
1317  				return NTLMv2;
1318  			break;
1319  		default:
1320  			break;
1321  		}
1322  		fallthrough;
1323  	default:
1324  		return Unspecified;
1325  	}
1326  }
1327  
1328  struct sess_data {
1329  	unsigned int xid;
1330  	struct cifs_ses *ses;
1331  	struct TCP_Server_Info *server;
1332  	struct nls_table *nls_cp;
1333  	void (*func)(struct sess_data *);
1334  	int result;
1335  
1336  	/* we will send the SMB in three pieces:
1337  	 * a fixed length beginning part, an optional
1338  	 * SPNEGO blob (which can be zero length), and a
1339  	 * last part which will include the strings
1340  	 * and rest of bcc area. This allows us to avoid
1341  	 * a large buffer 17K allocation
1342  	 */
1343  	int buf0_type;
1344  	struct kvec iov[3];
1345  };
1346  
1347  #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
1348  static int
sess_alloc_buffer(struct sess_data * sess_data,int wct)1349  sess_alloc_buffer(struct sess_data *sess_data, int wct)
1350  {
1351  	int rc;
1352  	struct cifs_ses *ses = sess_data->ses;
1353  	struct smb_hdr *smb_buf;
1354  
1355  	rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
1356  				  (void **)&smb_buf);
1357  
1358  	if (rc)
1359  		return rc;
1360  
1361  	sess_data->iov[0].iov_base = (char *)smb_buf;
1362  	sess_data->iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;
1363  	/*
1364  	 * This variable will be used to clear the buffer
1365  	 * allocated above in case of any error in the calling function.
1366  	 */
1367  	sess_data->buf0_type = CIFS_SMALL_BUFFER;
1368  
1369  	/* 2000 big enough to fit max user, domain, NOS name etc. */
1370  	sess_data->iov[2].iov_base = kmalloc(2000, GFP_KERNEL);
1371  	if (!sess_data->iov[2].iov_base) {
1372  		rc = -ENOMEM;
1373  		goto out_free_smb_buf;
1374  	}
1375  
1376  	return 0;
1377  
1378  out_free_smb_buf:
1379  	cifs_small_buf_release(smb_buf);
1380  	sess_data->iov[0].iov_base = NULL;
1381  	sess_data->iov[0].iov_len = 0;
1382  	sess_data->buf0_type = CIFS_NO_BUFFER;
1383  	return rc;
1384  }
1385  
1386  static void
sess_free_buffer(struct sess_data * sess_data)1387  sess_free_buffer(struct sess_data *sess_data)
1388  {
1389  	struct kvec *iov = sess_data->iov;
1390  
1391  	/*
1392  	 * Zero the session data before freeing, as it might contain sensitive info (keys, etc).
1393  	 * Note that iov[1] is already freed by caller.
1394  	 */
1395  	if (sess_data->buf0_type != CIFS_NO_BUFFER && iov[0].iov_base)
1396  		memzero_explicit(iov[0].iov_base, iov[0].iov_len);
1397  
1398  	free_rsp_buf(sess_data->buf0_type, iov[0].iov_base);
1399  	sess_data->buf0_type = CIFS_NO_BUFFER;
1400  	kfree_sensitive(iov[2].iov_base);
1401  }
1402  
1403  static int
sess_establish_session(struct sess_data * sess_data)1404  sess_establish_session(struct sess_data *sess_data)
1405  {
1406  	struct cifs_ses *ses = sess_data->ses;
1407  	struct TCP_Server_Info *server = sess_data->server;
1408  
1409  	cifs_server_lock(server);
1410  	if (!server->session_estab) {
1411  		if (server->sign) {
1412  			server->session_key.response =
1413  				kmemdup(ses->auth_key.response,
1414  				ses->auth_key.len, GFP_KERNEL);
1415  			if (!server->session_key.response) {
1416  				cifs_server_unlock(server);
1417  				return -ENOMEM;
1418  			}
1419  			server->session_key.len =
1420  						ses->auth_key.len;
1421  		}
1422  		server->sequence_number = 0x2;
1423  		server->session_estab = true;
1424  	}
1425  	cifs_server_unlock(server);
1426  
1427  	cifs_dbg(FYI, "CIFS session established successfully\n");
1428  	return 0;
1429  }
1430  
1431  static int
sess_sendreceive(struct sess_data * sess_data)1432  sess_sendreceive(struct sess_data *sess_data)
1433  {
1434  	int rc;
1435  	struct smb_hdr *smb_buf = (struct smb_hdr *) sess_data->iov[0].iov_base;
1436  	__u16 count;
1437  	struct kvec rsp_iov = { NULL, 0 };
1438  
1439  	count = sess_data->iov[1].iov_len + sess_data->iov[2].iov_len;
1440  	be32_add_cpu(&smb_buf->smb_buf_length, count);
1441  	put_bcc(count, smb_buf);
1442  
1443  	rc = SendReceive2(sess_data->xid, sess_data->ses,
1444  			  sess_data->iov, 3 /* num_iovecs */,
1445  			  &sess_data->buf0_type,
1446  			  CIFS_LOG_ERROR, &rsp_iov);
1447  	cifs_small_buf_release(sess_data->iov[0].iov_base);
1448  	memcpy(&sess_data->iov[0], &rsp_iov, sizeof(struct kvec));
1449  
1450  	return rc;
1451  }
1452  
1453  static void
sess_auth_ntlmv2(struct sess_data * sess_data)1454  sess_auth_ntlmv2(struct sess_data *sess_data)
1455  {
1456  	int rc = 0;
1457  	struct smb_hdr *smb_buf;
1458  	SESSION_SETUP_ANDX *pSMB;
1459  	char *bcc_ptr;
1460  	struct cifs_ses *ses = sess_data->ses;
1461  	struct TCP_Server_Info *server = sess_data->server;
1462  	__u32 capabilities;
1463  	__u16 bytes_remaining;
1464  
1465  	/* old style NTLM sessionsetup */
1466  	/* wct = 13 */
1467  	rc = sess_alloc_buffer(sess_data, 13);
1468  	if (rc)
1469  		goto out;
1470  
1471  	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1472  	bcc_ptr = sess_data->iov[2].iov_base;
1473  	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1474  
1475  	pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
1476  
1477  	/* LM2 password would be here if we supported it */
1478  	pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
1479  
1480  	if (ses->user_name != NULL) {
1481  		/* calculate nlmv2 response and session key */
1482  		rc = setup_ntlmv2_rsp(ses, sess_data->nls_cp);
1483  		if (rc) {
1484  			cifs_dbg(VFS, "Error %d during NTLMv2 authentication\n", rc);
1485  			goto out;
1486  		}
1487  
1488  		memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
1489  				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1490  		bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
1491  
1492  		/* set case sensitive password length after tilen may get
1493  		 * assigned, tilen is 0 otherwise.
1494  		 */
1495  		pSMB->req_no_secext.CaseSensitivePasswordLength =
1496  			cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1497  	} else {
1498  		pSMB->req_no_secext.CaseSensitivePasswordLength = 0;
1499  	}
1500  
1501  	if (ses->capabilities & CAP_UNICODE) {
1502  		if (!IS_ALIGNED(sess_data->iov[0].iov_len, 2)) {
1503  			*bcc_ptr = 0;
1504  			bcc_ptr++;
1505  		}
1506  		unicode_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1507  	} else {
1508  		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1509  	}
1510  
1511  
1512  	sess_data->iov[2].iov_len = (long) bcc_ptr -
1513  			(long) sess_data->iov[2].iov_base;
1514  
1515  	rc = sess_sendreceive(sess_data);
1516  	if (rc)
1517  		goto out;
1518  
1519  	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1520  	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1521  
1522  	if (smb_buf->WordCount != 3) {
1523  		rc = -EIO;
1524  		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1525  		goto out;
1526  	}
1527  
1528  	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1529  		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1530  
1531  	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1532  	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1533  
1534  	bytes_remaining = get_bcc(smb_buf);
1535  	bcc_ptr = pByteArea(smb_buf);
1536  
1537  	/* BB check if Unicode and decode strings */
1538  	if (bytes_remaining == 0) {
1539  		/* no string area to decode, do nothing */
1540  	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1541  		/* unicode string area must be word-aligned */
1542  		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1543  			++bcc_ptr;
1544  			--bytes_remaining;
1545  		}
1546  		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1547  				      sess_data->nls_cp);
1548  	} else {
1549  		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1550  				    sess_data->nls_cp);
1551  	}
1552  
1553  	rc = sess_establish_session(sess_data);
1554  out:
1555  	sess_data->result = rc;
1556  	sess_data->func = NULL;
1557  	sess_free_buffer(sess_data);
1558  	kfree_sensitive(ses->auth_key.response);
1559  	ses->auth_key.response = NULL;
1560  }
1561  
1562  #ifdef CONFIG_CIFS_UPCALL
1563  static void
sess_auth_kerberos(struct sess_data * sess_data)1564  sess_auth_kerberos(struct sess_data *sess_data)
1565  {
1566  	int rc = 0;
1567  	struct smb_hdr *smb_buf;
1568  	SESSION_SETUP_ANDX *pSMB;
1569  	char *bcc_ptr;
1570  	struct cifs_ses *ses = sess_data->ses;
1571  	struct TCP_Server_Info *server = sess_data->server;
1572  	__u32 capabilities;
1573  	__u16 bytes_remaining;
1574  	struct key *spnego_key = NULL;
1575  	struct cifs_spnego_msg *msg;
1576  	u16 blob_len;
1577  
1578  	/* extended security */
1579  	/* wct = 12 */
1580  	rc = sess_alloc_buffer(sess_data, 12);
1581  	if (rc)
1582  		goto out;
1583  
1584  	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1585  	bcc_ptr = sess_data->iov[2].iov_base;
1586  	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1587  
1588  	spnego_key = cifs_get_spnego_key(ses, server);
1589  	if (IS_ERR(spnego_key)) {
1590  		rc = PTR_ERR(spnego_key);
1591  		spnego_key = NULL;
1592  		goto out;
1593  	}
1594  
1595  	msg = spnego_key->payload.data[0];
1596  	/*
1597  	 * check version field to make sure that cifs.upcall is
1598  	 * sending us a response in an expected form
1599  	 */
1600  	if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
1601  		cifs_dbg(VFS, "incorrect version of cifs.upcall (expected %d but got %d)\n",
1602  			 CIFS_SPNEGO_UPCALL_VERSION, msg->version);
1603  		rc = -EKEYREJECTED;
1604  		goto out_put_spnego_key;
1605  	}
1606  
1607  	kfree_sensitive(ses->auth_key.response);
1608  	ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
1609  					 GFP_KERNEL);
1610  	if (!ses->auth_key.response) {
1611  		cifs_dbg(VFS, "Kerberos can't allocate (%u bytes) memory\n",
1612  			 msg->sesskey_len);
1613  		rc = -ENOMEM;
1614  		goto out_put_spnego_key;
1615  	}
1616  	ses->auth_key.len = msg->sesskey_len;
1617  
1618  	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
1619  	capabilities |= CAP_EXTENDED_SECURITY;
1620  	pSMB->req.Capabilities = cpu_to_le32(capabilities);
1621  	sess_data->iov[1].iov_base = msg->data + msg->sesskey_len;
1622  	sess_data->iov[1].iov_len = msg->secblob_len;
1623  	pSMB->req.SecurityBlobLength = cpu_to_le16(sess_data->iov[1].iov_len);
1624  
1625  	if (ses->capabilities & CAP_UNICODE) {
1626  		/* unicode strings must be word aligned */
1627  		if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
1628  			*bcc_ptr = 0;
1629  			bcc_ptr++;
1630  		}
1631  		unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1632  		unicode_domain_string(&bcc_ptr, ses, sess_data->nls_cp);
1633  	} else {
1634  		/* BB: is this right? */
1635  		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1636  	}
1637  
1638  	sess_data->iov[2].iov_len = (long) bcc_ptr -
1639  			(long) sess_data->iov[2].iov_base;
1640  
1641  	rc = sess_sendreceive(sess_data);
1642  	if (rc)
1643  		goto out_put_spnego_key;
1644  
1645  	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1646  	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1647  
1648  	if (smb_buf->WordCount != 4) {
1649  		rc = -EIO;
1650  		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1651  		goto out_put_spnego_key;
1652  	}
1653  
1654  	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1655  		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1656  
1657  	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1658  	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1659  
1660  	bytes_remaining = get_bcc(smb_buf);
1661  	bcc_ptr = pByteArea(smb_buf);
1662  
1663  	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1664  	if (blob_len > bytes_remaining) {
1665  		cifs_dbg(VFS, "bad security blob length %d\n",
1666  				blob_len);
1667  		rc = -EINVAL;
1668  		goto out_put_spnego_key;
1669  	}
1670  	bcc_ptr += blob_len;
1671  	bytes_remaining -= blob_len;
1672  
1673  	/* BB check if Unicode and decode strings */
1674  	if (bytes_remaining == 0) {
1675  		/* no string area to decode, do nothing */
1676  	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1677  		/* unicode string area must be word-aligned */
1678  		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1679  			++bcc_ptr;
1680  			--bytes_remaining;
1681  		}
1682  		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1683  				      sess_data->nls_cp);
1684  	} else {
1685  		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1686  				    sess_data->nls_cp);
1687  	}
1688  
1689  	rc = sess_establish_session(sess_data);
1690  out_put_spnego_key:
1691  	key_invalidate(spnego_key);
1692  	key_put(spnego_key);
1693  out:
1694  	sess_data->result = rc;
1695  	sess_data->func = NULL;
1696  	sess_free_buffer(sess_data);
1697  	kfree_sensitive(ses->auth_key.response);
1698  	ses->auth_key.response = NULL;
1699  }
1700  
1701  #endif /* ! CONFIG_CIFS_UPCALL */
1702  
1703  /*
1704   * The required kvec buffers have to be allocated before calling this
1705   * function.
1706   */
1707  static int
_sess_auth_rawntlmssp_assemble_req(struct sess_data * sess_data)1708  _sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
1709  {
1710  	SESSION_SETUP_ANDX *pSMB;
1711  	struct cifs_ses *ses = sess_data->ses;
1712  	struct TCP_Server_Info *server = sess_data->server;
1713  	__u32 capabilities;
1714  	char *bcc_ptr;
1715  
1716  	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1717  
1718  	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1719  	if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
1720  		cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
1721  		return -ENOSYS;
1722  	}
1723  
1724  	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
1725  	capabilities |= CAP_EXTENDED_SECURITY;
1726  	pSMB->req.Capabilities |= cpu_to_le32(capabilities);
1727  
1728  	bcc_ptr = sess_data->iov[2].iov_base;
1729  	/* unicode strings must be word aligned */
1730  	if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
1731  		*bcc_ptr = 0;
1732  		bcc_ptr++;
1733  	}
1734  	unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1735  
1736  	sess_data->iov[2].iov_len = (long) bcc_ptr -
1737  					(long) sess_data->iov[2].iov_base;
1738  
1739  	return 0;
1740  }
1741  
1742  static void
1743  sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data);
1744  
1745  static void
sess_auth_rawntlmssp_negotiate(struct sess_data * sess_data)1746  sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
1747  {
1748  	int rc;
1749  	struct smb_hdr *smb_buf;
1750  	SESSION_SETUP_ANDX *pSMB;
1751  	struct cifs_ses *ses = sess_data->ses;
1752  	struct TCP_Server_Info *server = sess_data->server;
1753  	__u16 bytes_remaining;
1754  	char *bcc_ptr;
1755  	unsigned char *ntlmsspblob = NULL;
1756  	u16 blob_len;
1757  
1758  	cifs_dbg(FYI, "rawntlmssp session setup negotiate phase\n");
1759  
1760  	/*
1761  	 * if memory allocation is successful, caller of this function
1762  	 * frees it.
1763  	 */
1764  	ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
1765  	if (!ses->ntlmssp) {
1766  		rc = -ENOMEM;
1767  		goto out;
1768  	}
1769  	ses->ntlmssp->sesskey_per_smbsess = false;
1770  
1771  	/* wct = 12 */
1772  	rc = sess_alloc_buffer(sess_data, 12);
1773  	if (rc)
1774  		goto out;
1775  
1776  	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1777  
1778  	/* Build security blob before we assemble the request */
1779  	rc = build_ntlmssp_negotiate_blob(&ntlmsspblob,
1780  				     &blob_len, ses, server,
1781  				     sess_data->nls_cp);
1782  	if (rc)
1783  		goto out_free_ntlmsspblob;
1784  
1785  	sess_data->iov[1].iov_len = blob_len;
1786  	sess_data->iov[1].iov_base = ntlmsspblob;
1787  	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
1788  
1789  	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
1790  	if (rc)
1791  		goto out_free_ntlmsspblob;
1792  
1793  	rc = sess_sendreceive(sess_data);
1794  
1795  	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1796  	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1797  
1798  	/* If true, rc here is expected and not an error */
1799  	if (sess_data->buf0_type != CIFS_NO_BUFFER &&
1800  	    smb_buf->Status.CifsError ==
1801  			cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))
1802  		rc = 0;
1803  
1804  	if (rc)
1805  		goto out_free_ntlmsspblob;
1806  
1807  	cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n");
1808  
1809  	if (smb_buf->WordCount != 4) {
1810  		rc = -EIO;
1811  		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1812  		goto out_free_ntlmsspblob;
1813  	}
1814  
1815  	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1816  	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1817  
1818  	bytes_remaining = get_bcc(smb_buf);
1819  	bcc_ptr = pByteArea(smb_buf);
1820  
1821  	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1822  	if (blob_len > bytes_remaining) {
1823  		cifs_dbg(VFS, "bad security blob length %d\n",
1824  				blob_len);
1825  		rc = -EINVAL;
1826  		goto out_free_ntlmsspblob;
1827  	}
1828  
1829  	rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
1830  
1831  out_free_ntlmsspblob:
1832  	kfree_sensitive(ntlmsspblob);
1833  out:
1834  	sess_free_buffer(sess_data);
1835  
1836  	if (!rc) {
1837  		sess_data->func = sess_auth_rawntlmssp_authenticate;
1838  		return;
1839  	}
1840  
1841  	/* Else error. Cleanup */
1842  	kfree_sensitive(ses->auth_key.response);
1843  	ses->auth_key.response = NULL;
1844  	kfree_sensitive(ses->ntlmssp);
1845  	ses->ntlmssp = NULL;
1846  
1847  	sess_data->func = NULL;
1848  	sess_data->result = rc;
1849  }
1850  
1851  static void
sess_auth_rawntlmssp_authenticate(struct sess_data * sess_data)1852  sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
1853  {
1854  	int rc;
1855  	struct smb_hdr *smb_buf;
1856  	SESSION_SETUP_ANDX *pSMB;
1857  	struct cifs_ses *ses = sess_data->ses;
1858  	struct TCP_Server_Info *server = sess_data->server;
1859  	__u16 bytes_remaining;
1860  	char *bcc_ptr;
1861  	unsigned char *ntlmsspblob = NULL;
1862  	u16 blob_len;
1863  
1864  	cifs_dbg(FYI, "rawntlmssp session setup authenticate phase\n");
1865  
1866  	/* wct = 12 */
1867  	rc = sess_alloc_buffer(sess_data, 12);
1868  	if (rc)
1869  		goto out;
1870  
1871  	/* Build security blob before we assemble the request */
1872  	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1873  	smb_buf = (struct smb_hdr *)pSMB;
1874  	rc = build_ntlmssp_auth_blob(&ntlmsspblob,
1875  					&blob_len, ses, server,
1876  					sess_data->nls_cp);
1877  	if (rc)
1878  		goto out_free_ntlmsspblob;
1879  	sess_data->iov[1].iov_len = blob_len;
1880  	sess_data->iov[1].iov_base = ntlmsspblob;
1881  	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
1882  	/*
1883  	 * Make sure that we tell the server that we are using
1884  	 * the uid that it just gave us back on the response
1885  	 * (challenge)
1886  	 */
1887  	smb_buf->Uid = ses->Suid;
1888  
1889  	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
1890  	if (rc)
1891  		goto out_free_ntlmsspblob;
1892  
1893  	rc = sess_sendreceive(sess_data);
1894  	if (rc)
1895  		goto out_free_ntlmsspblob;
1896  
1897  	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1898  	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1899  	if (smb_buf->WordCount != 4) {
1900  		rc = -EIO;
1901  		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1902  		goto out_free_ntlmsspblob;
1903  	}
1904  
1905  	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1906  		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1907  
1908  	if (ses->Suid != smb_buf->Uid) {
1909  		ses->Suid = smb_buf->Uid;
1910  		cifs_dbg(FYI, "UID changed! new UID = %llu\n", ses->Suid);
1911  	}
1912  
1913  	bytes_remaining = get_bcc(smb_buf);
1914  	bcc_ptr = pByteArea(smb_buf);
1915  	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1916  	if (blob_len > bytes_remaining) {
1917  		cifs_dbg(VFS, "bad security blob length %d\n",
1918  				blob_len);
1919  		rc = -EINVAL;
1920  		goto out_free_ntlmsspblob;
1921  	}
1922  	bcc_ptr += blob_len;
1923  	bytes_remaining -= blob_len;
1924  
1925  
1926  	/* BB check if Unicode and decode strings */
1927  	if (bytes_remaining == 0) {
1928  		/* no string area to decode, do nothing */
1929  	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1930  		/* unicode string area must be word-aligned */
1931  		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1932  			++bcc_ptr;
1933  			--bytes_remaining;
1934  		}
1935  		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1936  				      sess_data->nls_cp);
1937  	} else {
1938  		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1939  				    sess_data->nls_cp);
1940  	}
1941  
1942  out_free_ntlmsspblob:
1943  	kfree_sensitive(ntlmsspblob);
1944  out:
1945  	sess_free_buffer(sess_data);
1946  
1947  	if (!rc)
1948  		rc = sess_establish_session(sess_data);
1949  
1950  	/* Cleanup */
1951  	kfree_sensitive(ses->auth_key.response);
1952  	ses->auth_key.response = NULL;
1953  	kfree_sensitive(ses->ntlmssp);
1954  	ses->ntlmssp = NULL;
1955  
1956  	sess_data->func = NULL;
1957  	sess_data->result = rc;
1958  }
1959  
select_sec(struct sess_data * sess_data)1960  static int select_sec(struct sess_data *sess_data)
1961  {
1962  	int type;
1963  	struct cifs_ses *ses = sess_data->ses;
1964  	struct TCP_Server_Info *server = sess_data->server;
1965  
1966  	type = cifs_select_sectype(server, ses->sectype);
1967  	cifs_dbg(FYI, "sess setup type %d\n", type);
1968  	if (type == Unspecified) {
1969  		cifs_dbg(VFS, "Unable to select appropriate authentication method!\n");
1970  		return -EINVAL;
1971  	}
1972  
1973  	switch (type) {
1974  	case NTLMv2:
1975  		sess_data->func = sess_auth_ntlmv2;
1976  		break;
1977  	case Kerberos:
1978  #ifdef CONFIG_CIFS_UPCALL
1979  		sess_data->func = sess_auth_kerberos;
1980  		break;
1981  #else
1982  		cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
1983  		return -ENOSYS;
1984  #endif /* CONFIG_CIFS_UPCALL */
1985  	case RawNTLMSSP:
1986  		sess_data->func = sess_auth_rawntlmssp_negotiate;
1987  		break;
1988  	default:
1989  		cifs_dbg(VFS, "secType %d not supported!\n", type);
1990  		return -ENOSYS;
1991  	}
1992  
1993  	return 0;
1994  }
1995  
CIFS_SessSetup(const unsigned int xid,struct cifs_ses * ses,struct TCP_Server_Info * server,const struct nls_table * nls_cp)1996  int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
1997  		   struct TCP_Server_Info *server,
1998  		   const struct nls_table *nls_cp)
1999  {
2000  	int rc = 0;
2001  	struct sess_data *sess_data;
2002  
2003  	if (ses == NULL) {
2004  		WARN(1, "%s: ses == NULL!", __func__);
2005  		return -EINVAL;
2006  	}
2007  
2008  	sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
2009  	if (!sess_data)
2010  		return -ENOMEM;
2011  
2012  	sess_data->xid = xid;
2013  	sess_data->ses = ses;
2014  	sess_data->server = server;
2015  	sess_data->buf0_type = CIFS_NO_BUFFER;
2016  	sess_data->nls_cp = (struct nls_table *) nls_cp;
2017  
2018  	rc = select_sec(sess_data);
2019  	if (rc)
2020  		goto out;
2021  
2022  	while (sess_data->func)
2023  		sess_data->func(sess_data);
2024  
2025  	/* Store result before we free sess_data */
2026  	rc = sess_data->result;
2027  
2028  out:
2029  	kfree_sensitive(sess_data);
2030  	return rc;
2031  }
2032  #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
2033