xref: /linux/fs/smb/client/sess.c (revision 8e07e0e3964ca4e23ce7b68e2096fe660a888942)
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
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 
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
73 cifs_ses_get_chan_index(struct cifs_ses *ses,
74 			struct TCP_Server_Info *server)
75 {
76 	unsigned int i;
77 
78 	for (i = 0; i < ses->chan_count; i++) {
79 		if (ses->chans[i].server == server)
80 			return i;
81 	}
82 
83 	/* If we didn't find the channel, it is likely a bug */
84 	if (server)
85 		cifs_dbg(VFS, "unable to get chan index for server: 0x%llx",
86 			 server->conn_id);
87 	WARN_ON(1);
88 	return CIFS_INVAL_CHAN_INDEX;
89 }
90 
91 void
92 cifs_chan_set_in_reconnect(struct cifs_ses *ses,
93 			     struct TCP_Server_Info *server)
94 {
95 	int chan_index = cifs_ses_get_chan_index(ses, server);
96 
97 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
98 		return;
99 
100 	ses->chans[chan_index].in_reconnect = true;
101 }
102 
103 void
104 cifs_chan_clear_in_reconnect(struct cifs_ses *ses,
105 			     struct TCP_Server_Info *server)
106 {
107 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
108 
109 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
110 		return;
111 
112 	ses->chans[chan_index].in_reconnect = false;
113 }
114 
115 bool
116 cifs_chan_in_reconnect(struct cifs_ses *ses,
117 			  struct TCP_Server_Info *server)
118 {
119 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
120 
121 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
122 		return true;	/* err on the safer side */
123 
124 	return CIFS_CHAN_IN_RECONNECT(ses, chan_index);
125 }
126 
127 void
128 cifs_chan_set_need_reconnect(struct cifs_ses *ses,
129 			     struct TCP_Server_Info *server)
130 {
131 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
132 
133 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
134 		return;
135 
136 	set_bit(chan_index, &ses->chans_need_reconnect);
137 	cifs_dbg(FYI, "Set reconnect bitmask for chan %u; now 0x%lx\n",
138 		 chan_index, ses->chans_need_reconnect);
139 }
140 
141 void
142 cifs_chan_clear_need_reconnect(struct cifs_ses *ses,
143 			       struct TCP_Server_Info *server)
144 {
145 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
146 
147 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
148 		return;
149 
150 	clear_bit(chan_index, &ses->chans_need_reconnect);
151 	cifs_dbg(FYI, "Cleared reconnect bitmask for chan %u; now 0x%lx\n",
152 		 chan_index, ses->chans_need_reconnect);
153 }
154 
155 bool
156 cifs_chan_needs_reconnect(struct cifs_ses *ses,
157 			  struct TCP_Server_Info *server)
158 {
159 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
160 
161 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
162 		return true;	/* err on the safer side */
163 
164 	return CIFS_CHAN_NEEDS_RECONNECT(ses, chan_index);
165 }
166 
167 bool
168 cifs_chan_is_iface_active(struct cifs_ses *ses,
169 			  struct TCP_Server_Info *server)
170 {
171 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
172 
173 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
174 		return true;	/* err on the safer side */
175 
176 	return ses->chans[chan_index].iface &&
177 		ses->chans[chan_index].iface->is_active;
178 }
179 
180 /* returns number of channels added */
181 int cifs_try_adding_channels(struct cifs_ses *ses)
182 {
183 	struct TCP_Server_Info *server = ses->server;
184 	int old_chan_count, new_chan_count;
185 	int left;
186 	int rc = 0;
187 	int tries = 0;
188 	size_t iface_weight = 0, iface_min_speed = 0;
189 	struct cifs_server_iface *iface = NULL, *niface = NULL;
190 	struct cifs_server_iface *last_iface = NULL;
191 
192 	spin_lock(&ses->chan_lock);
193 
194 	new_chan_count = old_chan_count = ses->chan_count;
195 	left = ses->chan_max - ses->chan_count;
196 
197 	if (left <= 0) {
198 		spin_unlock(&ses->chan_lock);
199 		cifs_dbg(FYI,
200 			 "ses already at max_channels (%zu), nothing to open\n",
201 			 ses->chan_max);
202 		return 0;
203 	}
204 
205 	if (server->dialect < SMB30_PROT_ID) {
206 		spin_unlock(&ses->chan_lock);
207 		cifs_dbg(VFS, "multichannel is not supported on this protocol version, use 3.0 or above\n");
208 		return 0;
209 	}
210 
211 	if (!(server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
212 		spin_unlock(&ses->chan_lock);
213 		cifs_server_dbg(VFS, "no multichannel support\n");
214 		return 0;
215 	}
216 	spin_unlock(&ses->chan_lock);
217 
218 	while (left > 0) {
219 
220 		tries++;
221 		if (tries > 3*ses->chan_max) {
222 			cifs_dbg(VFS, "too many channel open attempts (%d channels left to open)\n",
223 				 left);
224 			break;
225 		}
226 
227 		spin_lock(&ses->iface_lock);
228 		if (!ses->iface_count) {
229 			spin_unlock(&ses->iface_lock);
230 			cifs_dbg(VFS, "server %s does not advertise interfaces\n",
231 				      ses->server->hostname);
232 			break;
233 		}
234 
235 		if (!iface)
236 			iface = list_first_entry(&ses->iface_list, struct cifs_server_iface,
237 						 iface_head);
238 		last_iface = list_last_entry(&ses->iface_list, struct cifs_server_iface,
239 					     iface_head);
240 		iface_min_speed = last_iface->speed;
241 
242 		list_for_each_entry_safe_from(iface, niface, &ses->iface_list,
243 				    iface_head) {
244 			/* do not mix rdma and non-rdma interfaces */
245 			if (iface->rdma_capable != ses->server->rdma)
246 				continue;
247 
248 			/* skip ifaces that are unusable */
249 			if (!iface->is_active ||
250 			    (is_ses_using_iface(ses, iface) &&
251 			     !iface->rss_capable))
252 				continue;
253 
254 			/* check if we already allocated enough channels */
255 			iface_weight = iface->speed / iface_min_speed;
256 
257 			if (iface->weight_fulfilled >= iface_weight)
258 				continue;
259 
260 			/* take ref before unlock */
261 			kref_get(&iface->refcount);
262 
263 			spin_unlock(&ses->iface_lock);
264 			rc = cifs_ses_add_channel(ses, iface);
265 			spin_lock(&ses->iface_lock);
266 
267 			if (rc) {
268 				cifs_dbg(VFS, "failed to open extra channel on iface:%pIS rc=%d\n",
269 					 &iface->sockaddr,
270 					 rc);
271 				kref_put(&iface->refcount, release_iface);
272 				continue;
273 			}
274 
275 			iface->num_channels++;
276 			iface->weight_fulfilled++;
277 			cifs_dbg(VFS, "successfully opened new channel on iface:%pIS\n",
278 				 &iface->sockaddr);
279 			break;
280 		}
281 
282 		/* reached end of list. reset weight_fulfilled and start over */
283 		if (list_entry_is_head(iface, &ses->iface_list, iface_head)) {
284 			list_for_each_entry(iface, &ses->iface_list, iface_head)
285 				iface->weight_fulfilled = 0;
286 			spin_unlock(&ses->iface_lock);
287 			iface = NULL;
288 			continue;
289 		}
290 		spin_unlock(&ses->iface_lock);
291 
292 		left--;
293 		new_chan_count++;
294 	}
295 
296 	return new_chan_count - old_chan_count;
297 }
298 
299 /*
300  * called when multichannel is disabled by the server.
301  * this always gets called from smb2_reconnect
302  * and cannot get called in parallel threads.
303  */
304 void
305 cifs_disable_secondary_channels(struct cifs_ses *ses)
306 {
307 	int i, chan_count;
308 	struct TCP_Server_Info *server;
309 	struct cifs_server_iface *iface;
310 
311 	spin_lock(&ses->chan_lock);
312 	chan_count = ses->chan_count;
313 	if (chan_count == 1)
314 		goto done;
315 
316 	ses->chan_count = 1;
317 
318 	/* for all secondary channels reset the need reconnect bit */
319 	ses->chans_need_reconnect &= 1;
320 
321 	for (i = 1; i < chan_count; i++) {
322 		iface = ses->chans[i].iface;
323 		server = ses->chans[i].server;
324 
325 		/*
326 		 * remove these references first, since we need to unlock
327 		 * the chan_lock here, since iface_lock is a higher lock
328 		 */
329 		ses->chans[i].iface = NULL;
330 		ses->chans[i].server = NULL;
331 		spin_unlock(&ses->chan_lock);
332 
333 		if (iface) {
334 			spin_lock(&ses->iface_lock);
335 			iface->num_channels--;
336 			if (iface->weight_fulfilled)
337 				iface->weight_fulfilled--;
338 			kref_put(&iface->refcount, release_iface);
339 			spin_unlock(&ses->iface_lock);
340 		}
341 
342 		if (server) {
343 			if (!server->terminate) {
344 				server->terminate = true;
345 				cifs_signal_cifsd_for_reconnect(server, false);
346 			}
347 			cifs_put_tcp_session(server, false);
348 		}
349 
350 		spin_lock(&ses->chan_lock);
351 	}
352 
353 done:
354 	spin_unlock(&ses->chan_lock);
355 }
356 
357 /*
358  * update the iface for the channel if necessary.
359  * will return 0 when iface is updated, 1 if removed, 2 otherwise
360  * Must be called with chan_lock held.
361  */
362 int
363 cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
364 {
365 	unsigned int chan_index;
366 	size_t iface_weight = 0, iface_min_speed = 0;
367 	struct cifs_server_iface *iface = NULL;
368 	struct cifs_server_iface *old_iface = NULL;
369 	struct cifs_server_iface *last_iface = NULL;
370 	struct sockaddr_storage ss;
371 	int rc = 0;
372 
373 	spin_lock(&ses->chan_lock);
374 	chan_index = cifs_ses_get_chan_index(ses, server);
375 	if (chan_index == CIFS_INVAL_CHAN_INDEX) {
376 		spin_unlock(&ses->chan_lock);
377 		return 0;
378 	}
379 
380 	if (ses->chans[chan_index].iface) {
381 		old_iface = ses->chans[chan_index].iface;
382 		if (old_iface->is_active) {
383 			spin_unlock(&ses->chan_lock);
384 			return 1;
385 		}
386 	}
387 	spin_unlock(&ses->chan_lock);
388 
389 	spin_lock(&server->srv_lock);
390 	ss = server->dstaddr;
391 	spin_unlock(&server->srv_lock);
392 
393 	spin_lock(&ses->iface_lock);
394 	if (!ses->iface_count) {
395 		spin_unlock(&ses->iface_lock);
396 		cifs_dbg(VFS, "server %s does not advertise interfaces\n", ses->server->hostname);
397 		return 0;
398 	}
399 
400 	last_iface = list_last_entry(&ses->iface_list, struct cifs_server_iface,
401 				     iface_head);
402 	iface_min_speed = last_iface->speed;
403 
404 	/* then look for a new one */
405 	list_for_each_entry(iface, &ses->iface_list, iface_head) {
406 		if (!chan_index) {
407 			/* if we're trying to get the updated iface for primary channel */
408 			if (!cifs_match_ipaddr((struct sockaddr *) &ss,
409 					       (struct sockaddr *) &iface->sockaddr))
410 				continue;
411 
412 			kref_get(&iface->refcount);
413 			break;
414 		}
415 
416 		/* do not mix rdma and non-rdma interfaces */
417 		if (iface->rdma_capable != server->rdma)
418 			continue;
419 
420 		if (!iface->is_active ||
421 		    (is_ses_using_iface(ses, iface) &&
422 		     !iface->rss_capable)) {
423 			continue;
424 		}
425 
426 		/* check if we already allocated enough channels */
427 		iface_weight = iface->speed / iface_min_speed;
428 
429 		if (iface->weight_fulfilled >= iface_weight)
430 			continue;
431 
432 		kref_get(&iface->refcount);
433 		break;
434 	}
435 
436 	if (list_entry_is_head(iface, &ses->iface_list, iface_head)) {
437 		rc = 1;
438 		iface = NULL;
439 		cifs_dbg(FYI, "unable to find a suitable iface\n");
440 	}
441 
442 	if (!iface) {
443 		cifs_dbg(FYI, "unable to get the interface matching: %pIS\n",
444 			 &ss);
445 		spin_unlock(&ses->iface_lock);
446 		return 0;
447 	}
448 
449 	/* now drop the ref to the current iface */
450 	if (old_iface) {
451 		cifs_dbg(FYI, "replacing iface: %pIS with %pIS\n",
452 			 &old_iface->sockaddr,
453 			 &iface->sockaddr);
454 
455 		old_iface->num_channels--;
456 		if (old_iface->weight_fulfilled)
457 			old_iface->weight_fulfilled--;
458 		iface->num_channels++;
459 		iface->weight_fulfilled++;
460 
461 		kref_put(&old_iface->refcount, release_iface);
462 	} else if (old_iface) {
463 		/* if a new candidate is not found, keep things as is */
464 		cifs_dbg(FYI, "could not replace iface: %pIS\n",
465 			 &old_iface->sockaddr);
466 	} else if (!chan_index) {
467 		/* special case: update interface for primary channel */
468 		if (iface) {
469 			cifs_dbg(FYI, "referencing primary channel iface: %pIS\n",
470 				 &iface->sockaddr);
471 			iface->num_channels++;
472 			iface->weight_fulfilled++;
473 		}
474 	}
475 	spin_unlock(&ses->iface_lock);
476 
477 	if (iface) {
478 		spin_lock(&ses->chan_lock);
479 		chan_index = cifs_ses_get_chan_index(ses, server);
480 		if (chan_index == CIFS_INVAL_CHAN_INDEX) {
481 			spin_unlock(&ses->chan_lock);
482 			return 0;
483 		}
484 
485 		ses->chans[chan_index].iface = iface;
486 		spin_unlock(&ses->chan_lock);
487 	}
488 
489 	return rc;
490 }
491 
492 /*
493  * If server is a channel of ses, return the corresponding enclosing
494  * cifs_chan otherwise return NULL.
495  */
496 struct cifs_chan *
497 cifs_ses_find_chan(struct cifs_ses *ses, struct TCP_Server_Info *server)
498 {
499 	int i;
500 
501 	spin_lock(&ses->chan_lock);
502 	for (i = 0; i < ses->chan_count; i++) {
503 		if (ses->chans[i].server == server) {
504 			spin_unlock(&ses->chan_lock);
505 			return &ses->chans[i];
506 		}
507 	}
508 	spin_unlock(&ses->chan_lock);
509 	return NULL;
510 }
511 
512 static int
513 cifs_ses_add_channel(struct cifs_ses *ses,
514 		     struct cifs_server_iface *iface)
515 {
516 	struct TCP_Server_Info *chan_server;
517 	struct cifs_chan *chan;
518 	struct smb3_fs_context *ctx;
519 	static const char unc_fmt[] = "\\%s\\foo";
520 	struct sockaddr_in *ipv4 = (struct sockaddr_in *)&iface->sockaddr;
521 	struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&iface->sockaddr;
522 	size_t len;
523 	int rc;
524 	unsigned int xid = get_xid();
525 
526 	if (iface->sockaddr.ss_family == AF_INET)
527 		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI4)\n",
528 			 ses, iface->speed, iface->rdma_capable ? "yes" : "no",
529 			 &ipv4->sin_addr);
530 	else
531 		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI6)\n",
532 			 ses, iface->speed, iface->rdma_capable ? "yes" : "no",
533 			 &ipv6->sin6_addr);
534 
535 	/*
536 	 * Setup a ctx with mostly the same info as the existing
537 	 * session and overwrite it with the requested iface data.
538 	 *
539 	 * We need to setup at least the fields used for negprot and
540 	 * sesssetup.
541 	 *
542 	 * We only need the ctx here, so we can reuse memory from
543 	 * the session and server without caring about memory
544 	 * management.
545 	 */
546 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
547 	if (!ctx) {
548 		rc = -ENOMEM;
549 		goto out_free_xid;
550 	}
551 
552 	/* Always make new connection for now (TODO?) */
553 	ctx->nosharesock = true;
554 
555 	/* Auth */
556 	ctx->domainauto = ses->domainAuto;
557 	ctx->domainname = ses->domainName;
558 
559 	/* no hostname for extra channels */
560 	ctx->server_hostname = "";
561 
562 	ctx->username = ses->user_name;
563 	ctx->password = ses->password;
564 	ctx->sectype = ses->sectype;
565 	ctx->sign = ses->sign;
566 
567 	/* UNC and paths */
568 	/* XXX: Use ses->server->hostname? */
569 	len = sizeof(unc_fmt) + SERVER_NAME_LEN_WITH_NULL;
570 	ctx->UNC = kzalloc(len, GFP_KERNEL);
571 	if (!ctx->UNC) {
572 		rc = -ENOMEM;
573 		goto out_free_ctx;
574 	}
575 	scnprintf(ctx->UNC, len, unc_fmt, ses->ip_addr);
576 	ctx->prepath = "";
577 
578 	/* Reuse same version as master connection */
579 	ctx->vals = ses->server->vals;
580 	ctx->ops = ses->server->ops;
581 
582 	ctx->noblocksnd = ses->server->noblocksnd;
583 	ctx->noautotune = ses->server->noautotune;
584 	ctx->sockopt_tcp_nodelay = ses->server->tcp_nodelay;
585 	ctx->echo_interval = ses->server->echo_interval / HZ;
586 	ctx->max_credits = ses->server->max_credits;
587 
588 	/*
589 	 * This will be used for encoding/decoding user/domain/pw
590 	 * during sess setup auth.
591 	 */
592 	ctx->local_nls = ses->local_nls;
593 
594 	/* Use RDMA if possible */
595 	ctx->rdma = iface->rdma_capable;
596 	memcpy(&ctx->dstaddr, &iface->sockaddr, sizeof(ctx->dstaddr));
597 
598 	/* reuse master con client guid */
599 	memcpy(&ctx->client_guid, ses->server->client_guid,
600 	       sizeof(ctx->client_guid));
601 	ctx->use_client_guid = true;
602 
603 	chan_server = cifs_get_tcp_session(ctx, ses->server);
604 
605 	spin_lock(&ses->chan_lock);
606 	chan = &ses->chans[ses->chan_count];
607 	chan->server = chan_server;
608 	if (IS_ERR(chan->server)) {
609 		rc = PTR_ERR(chan->server);
610 		chan->server = NULL;
611 		spin_unlock(&ses->chan_lock);
612 		goto out;
613 	}
614 	chan->iface = iface;
615 	ses->chan_count++;
616 	atomic_set(&ses->chan_seq, 0);
617 
618 	/* Mark this channel as needing connect/setup */
619 	cifs_chan_set_need_reconnect(ses, chan->server);
620 
621 	spin_unlock(&ses->chan_lock);
622 
623 	mutex_lock(&ses->session_mutex);
624 	/*
625 	 * We need to allocate the server crypto now as we will need
626 	 * to sign packets before we generate the channel signing key
627 	 * (we sign with the session key)
628 	 */
629 	rc = smb311_crypto_shash_allocate(chan->server);
630 	if (rc) {
631 		cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
632 		mutex_unlock(&ses->session_mutex);
633 		goto out;
634 	}
635 
636 	rc = cifs_negotiate_protocol(xid, ses, chan->server);
637 	if (!rc)
638 		rc = cifs_setup_session(xid, ses, chan->server, ses->local_nls);
639 
640 	mutex_unlock(&ses->session_mutex);
641 
642 out:
643 	if (rc && chan->server) {
644 		cifs_put_tcp_session(chan->server, 0);
645 
646 		spin_lock(&ses->chan_lock);
647 
648 		/* we rely on all bits beyond chan_count to be clear */
649 		cifs_chan_clear_need_reconnect(ses, chan->server);
650 		ses->chan_count--;
651 		/*
652 		 * chan_count should never reach 0 as at least the primary
653 		 * channel is always allocated
654 		 */
655 		WARN_ON(ses->chan_count < 1);
656 		spin_unlock(&ses->chan_lock);
657 	}
658 
659 	kfree(ctx->UNC);
660 out_free_ctx:
661 	kfree(ctx);
662 out_free_xid:
663 	free_xid(xid);
664 	return rc;
665 }
666 
667 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
668 static __u32 cifs_ssetup_hdr(struct cifs_ses *ses,
669 			     struct TCP_Server_Info *server,
670 			     SESSION_SETUP_ANDX *pSMB)
671 {
672 	__u32 capabilities = 0;
673 
674 	/* init fields common to all four types of SessSetup */
675 	/* Note that offsets for first seven fields in req struct are same  */
676 	/*	in CIFS Specs so does not matter which of 3 forms of struct */
677 	/*	that we use in next few lines                               */
678 	/* Note that header is initialized to zero in header_assemble */
679 	pSMB->req.AndXCommand = 0xFF;
680 	pSMB->req.MaxBufferSize = cpu_to_le16(min_t(u32,
681 					CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4,
682 					USHRT_MAX));
683 	pSMB->req.MaxMpxCount = cpu_to_le16(server->maxReq);
684 	pSMB->req.VcNumber = cpu_to_le16(1);
685 
686 	/* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
687 
688 	/* BB verify whether signing required on neg or just auth frame (and NTLM case) */
689 
690 	capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
691 			CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
692 
693 	if (server->sign)
694 		pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
695 
696 	if (ses->capabilities & CAP_UNICODE) {
697 		pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
698 		capabilities |= CAP_UNICODE;
699 	}
700 	if (ses->capabilities & CAP_STATUS32) {
701 		pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
702 		capabilities |= CAP_STATUS32;
703 	}
704 	if (ses->capabilities & CAP_DFS) {
705 		pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
706 		capabilities |= CAP_DFS;
707 	}
708 	if (ses->capabilities & CAP_UNIX)
709 		capabilities |= CAP_UNIX;
710 
711 	return capabilities;
712 }
713 
714 static void
715 unicode_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
716 {
717 	char *bcc_ptr = *pbcc_area;
718 	int bytes_ret = 0;
719 
720 	/* Copy OS version */
721 	bytes_ret = cifs_strtoUTF16((__le16 *)bcc_ptr, "Linux version ", 32,
722 				    nls_cp);
723 	bcc_ptr += 2 * bytes_ret;
724 	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, init_utsname()->release,
725 				    32, nls_cp);
726 	bcc_ptr += 2 * bytes_ret;
727 	bcc_ptr += 2; /* trailing null */
728 
729 	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
730 				    32, nls_cp);
731 	bcc_ptr += 2 * bytes_ret;
732 	bcc_ptr += 2; /* trailing null */
733 
734 	*pbcc_area = bcc_ptr;
735 }
736 
737 static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
738 				   const struct nls_table *nls_cp)
739 {
740 	char *bcc_ptr = *pbcc_area;
741 	int bytes_ret = 0;
742 
743 	/* copy domain */
744 	if (ses->domainName == NULL) {
745 		/*
746 		 * Sending null domain better than using a bogus domain name (as
747 		 * we did briefly in 2.6.18) since server will use its default
748 		 */
749 		*bcc_ptr = 0;
750 		*(bcc_ptr+1) = 0;
751 		bytes_ret = 0;
752 	} else
753 		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
754 					    CIFS_MAX_DOMAINNAME_LEN, nls_cp);
755 	bcc_ptr += 2 * bytes_ret;
756 	bcc_ptr += 2;  /* account for null terminator */
757 
758 	*pbcc_area = bcc_ptr;
759 }
760 
761 static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
762 				   const struct nls_table *nls_cp)
763 {
764 	char *bcc_ptr = *pbcc_area;
765 	int bytes_ret = 0;
766 
767 	/* BB FIXME add check that strings less than 335 or will need to send as arrays */
768 
769 	/* copy user */
770 	if (ses->user_name == NULL) {
771 		/* null user mount */
772 		*bcc_ptr = 0;
773 		*(bcc_ptr+1) = 0;
774 	} else {
775 		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->user_name,
776 					    CIFS_MAX_USERNAME_LEN, nls_cp);
777 	}
778 	bcc_ptr += 2 * bytes_ret;
779 	bcc_ptr += 2; /* account for null termination */
780 
781 	unicode_domain_string(&bcc_ptr, ses, nls_cp);
782 	unicode_oslm_strings(&bcc_ptr, nls_cp);
783 
784 	*pbcc_area = bcc_ptr;
785 }
786 
787 static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
788 				 const struct nls_table *nls_cp)
789 {
790 	char *bcc_ptr = *pbcc_area;
791 	int len;
792 
793 	/* copy user */
794 	/* BB what about null user mounts - check that we do this BB */
795 	/* copy user */
796 	if (ses->user_name != NULL) {
797 		len = strscpy(bcc_ptr, ses->user_name, CIFS_MAX_USERNAME_LEN);
798 		if (WARN_ON_ONCE(len < 0))
799 			len = CIFS_MAX_USERNAME_LEN - 1;
800 		bcc_ptr += len;
801 	}
802 	/* else null user mount */
803 	*bcc_ptr = 0;
804 	bcc_ptr++; /* account for null termination */
805 
806 	/* copy domain */
807 	if (ses->domainName != NULL) {
808 		len = strscpy(bcc_ptr, ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
809 		if (WARN_ON_ONCE(len < 0))
810 			len = CIFS_MAX_DOMAINNAME_LEN - 1;
811 		bcc_ptr += len;
812 	} /* else we send a null domain name so server will default to its own domain */
813 	*bcc_ptr = 0;
814 	bcc_ptr++;
815 
816 	/* BB check for overflow here */
817 
818 	strcpy(bcc_ptr, "Linux version ");
819 	bcc_ptr += strlen("Linux version ");
820 	strcpy(bcc_ptr, init_utsname()->release);
821 	bcc_ptr += strlen(init_utsname()->release) + 1;
822 
823 	strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
824 	bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;
825 
826 	*pbcc_area = bcc_ptr;
827 }
828 
829 static void
830 decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifs_ses *ses,
831 		      const struct nls_table *nls_cp)
832 {
833 	int len;
834 	char *data = *pbcc_area;
835 
836 	cifs_dbg(FYI, "bleft %d\n", bleft);
837 
838 	kfree(ses->serverOS);
839 	ses->serverOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
840 	cifs_dbg(FYI, "serverOS=%s\n", ses->serverOS);
841 	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
842 	data += len;
843 	bleft -= len;
844 	if (bleft <= 0)
845 		return;
846 
847 	kfree(ses->serverNOS);
848 	ses->serverNOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
849 	cifs_dbg(FYI, "serverNOS=%s\n", ses->serverNOS);
850 	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
851 	data += len;
852 	bleft -= len;
853 	if (bleft <= 0)
854 		return;
855 
856 	kfree(ses->serverDomain);
857 	ses->serverDomain = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
858 	cifs_dbg(FYI, "serverDomain=%s\n", ses->serverDomain);
859 
860 	return;
861 }
862 
863 static void decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
864 				struct cifs_ses *ses,
865 				const struct nls_table *nls_cp)
866 {
867 	int len;
868 	char *bcc_ptr = *pbcc_area;
869 
870 	cifs_dbg(FYI, "decode sessetup ascii. bleft %d\n", bleft);
871 
872 	len = strnlen(bcc_ptr, bleft);
873 	if (len >= bleft)
874 		return;
875 
876 	kfree(ses->serverOS);
877 
878 	ses->serverOS = kmalloc(len + 1, GFP_KERNEL);
879 	if (ses->serverOS) {
880 		memcpy(ses->serverOS, bcc_ptr, len);
881 		ses->serverOS[len] = 0;
882 		if (strncmp(ses->serverOS, "OS/2", 4) == 0)
883 			cifs_dbg(FYI, "OS/2 server\n");
884 	}
885 
886 	bcc_ptr += len + 1;
887 	bleft -= len + 1;
888 
889 	len = strnlen(bcc_ptr, bleft);
890 	if (len >= bleft)
891 		return;
892 
893 	kfree(ses->serverNOS);
894 
895 	ses->serverNOS = kmalloc(len + 1, GFP_KERNEL);
896 	if (ses->serverNOS) {
897 		memcpy(ses->serverNOS, bcc_ptr, len);
898 		ses->serverNOS[len] = 0;
899 	}
900 
901 	bcc_ptr += len + 1;
902 	bleft -= len + 1;
903 
904 	len = strnlen(bcc_ptr, bleft);
905 	if (len > bleft)
906 		return;
907 
908 	/*
909 	 * No domain field in LANMAN case. Domain is
910 	 * returned by old servers in the SMB negprot response
911 	 *
912 	 * BB For newer servers which do not support Unicode,
913 	 * but thus do return domain here, we could add parsing
914 	 * for it later, but it is not very important
915 	 */
916 	cifs_dbg(FYI, "ascii: bytes left %d\n", bleft);
917 }
918 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
919 
920 int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
921 				    struct cifs_ses *ses)
922 {
923 	unsigned int tioffset; /* challenge message target info area */
924 	unsigned int tilen; /* challenge message target info area length  */
925 	CHALLENGE_MESSAGE *pblob = (CHALLENGE_MESSAGE *)bcc_ptr;
926 	__u32 server_flags;
927 
928 	if (blob_len < sizeof(CHALLENGE_MESSAGE)) {
929 		cifs_dbg(VFS, "challenge blob len %d too small\n", blob_len);
930 		return -EINVAL;
931 	}
932 
933 	if (memcmp(pblob->Signature, "NTLMSSP", 8)) {
934 		cifs_dbg(VFS, "blob signature incorrect %s\n",
935 			 pblob->Signature);
936 		return -EINVAL;
937 	}
938 	if (pblob->MessageType != NtLmChallenge) {
939 		cifs_dbg(VFS, "Incorrect message type %d\n",
940 			 pblob->MessageType);
941 		return -EINVAL;
942 	}
943 
944 	server_flags = le32_to_cpu(pblob->NegotiateFlags);
945 	cifs_dbg(FYI, "%s: negotiate=0x%08x challenge=0x%08x\n", __func__,
946 		 ses->ntlmssp->client_flags, server_flags);
947 
948 	if ((ses->ntlmssp->client_flags & (NTLMSSP_NEGOTIATE_SEAL | NTLMSSP_NEGOTIATE_SIGN)) &&
949 	    (!(server_flags & NTLMSSP_NEGOTIATE_56) && !(server_flags & NTLMSSP_NEGOTIATE_128))) {
950 		cifs_dbg(VFS, "%s: requested signing/encryption but server did not return either 56-bit or 128-bit session key size\n",
951 			 __func__);
952 		return -EINVAL;
953 	}
954 	if (!(server_flags & NTLMSSP_NEGOTIATE_NTLM) && !(server_flags & NTLMSSP_NEGOTIATE_EXTENDED_SEC)) {
955 		cifs_dbg(VFS, "%s: server does not seem to support either NTLMv1 or NTLMv2\n", __func__);
956 		return -EINVAL;
957 	}
958 	if (ses->server->sign && !(server_flags & NTLMSSP_NEGOTIATE_SIGN)) {
959 		cifs_dbg(VFS, "%s: forced packet signing but server does not seem to support it\n",
960 			 __func__);
961 		return -EOPNOTSUPP;
962 	}
963 	if ((ses->ntlmssp->client_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
964 	    !(server_flags & NTLMSSP_NEGOTIATE_KEY_XCH))
965 		pr_warn_once("%s: authentication has been weakened as server does not support key exchange\n",
966 			     __func__);
967 
968 	ses->ntlmssp->server_flags = server_flags;
969 
970 	memcpy(ses->ntlmssp->cryptkey, pblob->Challenge, CIFS_CRYPTO_KEY_SIZE);
971 	/*
972 	 * In particular we can examine sign flags
973 	 *
974 	 * BB spec says that if AvId field of MsvAvTimestamp is populated then
975 	 * we must set the MIC field of the AUTHENTICATE_MESSAGE
976 	 */
977 
978 	tioffset = le32_to_cpu(pblob->TargetInfoArray.BufferOffset);
979 	tilen = le16_to_cpu(pblob->TargetInfoArray.Length);
980 	if (tioffset > blob_len || tioffset + tilen > blob_len) {
981 		cifs_dbg(VFS, "tioffset + tilen too high %u + %u\n",
982 			 tioffset, tilen);
983 		return -EINVAL;
984 	}
985 	if (tilen) {
986 		kfree_sensitive(ses->auth_key.response);
987 		ses->auth_key.response = kmemdup(bcc_ptr + tioffset, tilen,
988 						 GFP_KERNEL);
989 		if (!ses->auth_key.response) {
990 			cifs_dbg(VFS, "Challenge target info alloc failure\n");
991 			return -ENOMEM;
992 		}
993 		ses->auth_key.len = tilen;
994 	}
995 
996 	return 0;
997 }
998 
999 static int size_of_ntlmssp_blob(struct cifs_ses *ses, int base_size)
1000 {
1001 	int sz = base_size + ses->auth_key.len
1002 		- CIFS_SESS_KEY_SIZE + CIFS_CPHTXT_SIZE + 2;
1003 
1004 	if (ses->domainName)
1005 		sz += sizeof(__le16) * strnlen(ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
1006 	else
1007 		sz += sizeof(__le16);
1008 
1009 	if (ses->user_name)
1010 		sz += sizeof(__le16) * strnlen(ses->user_name, CIFS_MAX_USERNAME_LEN);
1011 	else
1012 		sz += sizeof(__le16);
1013 
1014 	if (ses->workstation_name[0])
1015 		sz += sizeof(__le16) * strnlen(ses->workstation_name,
1016 					       ntlmssp_workstation_name_size(ses));
1017 	else
1018 		sz += sizeof(__le16);
1019 
1020 	return sz;
1021 }
1022 
1023 static inline void cifs_security_buffer_from_str(SECURITY_BUFFER *pbuf,
1024 						 char *str_value,
1025 						 int str_length,
1026 						 unsigned char *pstart,
1027 						 unsigned char **pcur,
1028 						 const struct nls_table *nls_cp)
1029 {
1030 	unsigned char *tmp = pstart;
1031 	int len;
1032 
1033 	if (!pbuf)
1034 		return;
1035 
1036 	if (!pcur)
1037 		pcur = &tmp;
1038 
1039 	if (!str_value) {
1040 		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
1041 		pbuf->Length = 0;
1042 		pbuf->MaximumLength = 0;
1043 		*pcur += sizeof(__le16);
1044 	} else {
1045 		len = cifs_strtoUTF16((__le16 *)*pcur,
1046 				      str_value,
1047 				      str_length,
1048 				      nls_cp);
1049 		len *= sizeof(__le16);
1050 		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
1051 		pbuf->Length = cpu_to_le16(len);
1052 		pbuf->MaximumLength = cpu_to_le16(len);
1053 		*pcur += len;
1054 	}
1055 }
1056 
1057 /* BB Move to ntlmssp.c eventually */
1058 
1059 int build_ntlmssp_negotiate_blob(unsigned char **pbuffer,
1060 				 u16 *buflen,
1061 				 struct cifs_ses *ses,
1062 				 struct TCP_Server_Info *server,
1063 				 const struct nls_table *nls_cp)
1064 {
1065 	int rc = 0;
1066 	NEGOTIATE_MESSAGE *sec_blob;
1067 	__u32 flags;
1068 	unsigned char *tmp;
1069 	int len;
1070 
1071 	len = size_of_ntlmssp_blob(ses, sizeof(NEGOTIATE_MESSAGE));
1072 	*pbuffer = kmalloc(len, GFP_KERNEL);
1073 	if (!*pbuffer) {
1074 		rc = -ENOMEM;
1075 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1076 		*buflen = 0;
1077 		goto setup_ntlm_neg_ret;
1078 	}
1079 	sec_blob = (NEGOTIATE_MESSAGE *)*pbuffer;
1080 
1081 	memset(*pbuffer, 0, sizeof(NEGOTIATE_MESSAGE));
1082 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1083 	sec_blob->MessageType = NtLmNegotiate;
1084 
1085 	/* BB is NTLMV2 session security format easier to use here? */
1086 	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
1087 		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
1088 		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
1089 		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
1090 		NTLMSSP_NEGOTIATE_SIGN;
1091 	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
1092 		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
1093 
1094 	tmp = *pbuffer + sizeof(NEGOTIATE_MESSAGE);
1095 	ses->ntlmssp->client_flags = flags;
1096 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1097 
1098 	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
1099 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1100 				      NULL,
1101 				      CIFS_MAX_DOMAINNAME_LEN,
1102 				      *pbuffer, &tmp,
1103 				      nls_cp);
1104 
1105 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1106 				      NULL,
1107 				      CIFS_MAX_WORKSTATION_LEN,
1108 				      *pbuffer, &tmp,
1109 				      nls_cp);
1110 
1111 	*buflen = tmp - *pbuffer;
1112 setup_ntlm_neg_ret:
1113 	return rc;
1114 }
1115 
1116 /*
1117  * Build ntlmssp blob with additional fields, such as version,
1118  * supported by modern servers. For safety limit to SMB3 or later
1119  * See notes in MS-NLMP Section 2.2.2.1 e.g.
1120  */
1121 int build_ntlmssp_smb3_negotiate_blob(unsigned char **pbuffer,
1122 				 u16 *buflen,
1123 				 struct cifs_ses *ses,
1124 				 struct TCP_Server_Info *server,
1125 				 const struct nls_table *nls_cp)
1126 {
1127 	int rc = 0;
1128 	struct negotiate_message *sec_blob;
1129 	__u32 flags;
1130 	unsigned char *tmp;
1131 	int len;
1132 
1133 	len = size_of_ntlmssp_blob(ses, sizeof(struct negotiate_message));
1134 	*pbuffer = kmalloc(len, GFP_KERNEL);
1135 	if (!*pbuffer) {
1136 		rc = -ENOMEM;
1137 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1138 		*buflen = 0;
1139 		goto setup_ntlm_smb3_neg_ret;
1140 	}
1141 	sec_blob = (struct negotiate_message *)*pbuffer;
1142 
1143 	memset(*pbuffer, 0, sizeof(struct negotiate_message));
1144 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1145 	sec_blob->MessageType = NtLmNegotiate;
1146 
1147 	/* BB is NTLMV2 session security format easier to use here? */
1148 	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
1149 		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
1150 		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
1151 		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
1152 		NTLMSSP_NEGOTIATE_SIGN | NTLMSSP_NEGOTIATE_VERSION;
1153 	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
1154 		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
1155 
1156 	sec_blob->Version.ProductMajorVersion = LINUX_VERSION_MAJOR;
1157 	sec_blob->Version.ProductMinorVersion = LINUX_VERSION_PATCHLEVEL;
1158 	sec_blob->Version.ProductBuild = cpu_to_le16(SMB3_PRODUCT_BUILD);
1159 	sec_blob->Version.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
1160 
1161 	tmp = *pbuffer + sizeof(struct negotiate_message);
1162 	ses->ntlmssp->client_flags = flags;
1163 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1164 
1165 	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
1166 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1167 				      NULL,
1168 				      CIFS_MAX_DOMAINNAME_LEN,
1169 				      *pbuffer, &tmp,
1170 				      nls_cp);
1171 
1172 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1173 				      NULL,
1174 				      CIFS_MAX_WORKSTATION_LEN,
1175 				      *pbuffer, &tmp,
1176 				      nls_cp);
1177 
1178 	*buflen = tmp - *pbuffer;
1179 setup_ntlm_smb3_neg_ret:
1180 	return rc;
1181 }
1182 
1183 
1184 /* See MS-NLMP 2.2.1.3 */
1185 int build_ntlmssp_auth_blob(unsigned char **pbuffer,
1186 					u16 *buflen,
1187 				   struct cifs_ses *ses,
1188 				   struct TCP_Server_Info *server,
1189 				   const struct nls_table *nls_cp)
1190 {
1191 	int rc;
1192 	AUTHENTICATE_MESSAGE *sec_blob;
1193 	__u32 flags;
1194 	unsigned char *tmp;
1195 	int len;
1196 
1197 	rc = setup_ntlmv2_rsp(ses, nls_cp);
1198 	if (rc) {
1199 		cifs_dbg(VFS, "Error %d during NTLMSSP authentication\n", rc);
1200 		*buflen = 0;
1201 		goto setup_ntlmv2_ret;
1202 	}
1203 
1204 	len = size_of_ntlmssp_blob(ses, sizeof(AUTHENTICATE_MESSAGE));
1205 	*pbuffer = kmalloc(len, GFP_KERNEL);
1206 	if (!*pbuffer) {
1207 		rc = -ENOMEM;
1208 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1209 		*buflen = 0;
1210 		goto setup_ntlmv2_ret;
1211 	}
1212 	sec_blob = (AUTHENTICATE_MESSAGE *)*pbuffer;
1213 
1214 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1215 	sec_blob->MessageType = NtLmAuthenticate;
1216 
1217 	/* send version information in ntlmssp authenticate also */
1218 	flags = ses->ntlmssp->server_flags | NTLMSSP_REQUEST_TARGET |
1219 		NTLMSSP_NEGOTIATE_TARGET_INFO | NTLMSSP_NEGOTIATE_VERSION |
1220 		NTLMSSP_NEGOTIATE_WORKSTATION_SUPPLIED;
1221 
1222 	sec_blob->Version.ProductMajorVersion = LINUX_VERSION_MAJOR;
1223 	sec_blob->Version.ProductMinorVersion = LINUX_VERSION_PATCHLEVEL;
1224 	sec_blob->Version.ProductBuild = cpu_to_le16(SMB3_PRODUCT_BUILD);
1225 	sec_blob->Version.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
1226 
1227 	tmp = *pbuffer + sizeof(AUTHENTICATE_MESSAGE);
1228 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1229 
1230 	sec_blob->LmChallengeResponse.BufferOffset =
1231 				cpu_to_le32(sizeof(AUTHENTICATE_MESSAGE));
1232 	sec_blob->LmChallengeResponse.Length = 0;
1233 	sec_blob->LmChallengeResponse.MaximumLength = 0;
1234 
1235 	sec_blob->NtChallengeResponse.BufferOffset =
1236 				cpu_to_le32(tmp - *pbuffer);
1237 	if (ses->user_name != NULL) {
1238 		memcpy(tmp, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
1239 				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1240 		tmp += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
1241 
1242 		sec_blob->NtChallengeResponse.Length =
1243 				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1244 		sec_blob->NtChallengeResponse.MaximumLength =
1245 				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1246 	} else {
1247 		/*
1248 		 * don't send an NT Response for anonymous access
1249 		 */
1250 		sec_blob->NtChallengeResponse.Length = 0;
1251 		sec_blob->NtChallengeResponse.MaximumLength = 0;
1252 	}
1253 
1254 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1255 				      ses->domainName,
1256 				      CIFS_MAX_DOMAINNAME_LEN,
1257 				      *pbuffer, &tmp,
1258 				      nls_cp);
1259 
1260 	cifs_security_buffer_from_str(&sec_blob->UserName,
1261 				      ses->user_name,
1262 				      CIFS_MAX_USERNAME_LEN,
1263 				      *pbuffer, &tmp,
1264 				      nls_cp);
1265 
1266 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1267 				      ses->workstation_name,
1268 				      ntlmssp_workstation_name_size(ses),
1269 				      *pbuffer, &tmp,
1270 				      nls_cp);
1271 
1272 	if ((ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
1273 	    (!ses->server->session_estab || ses->ntlmssp->sesskey_per_smbsess) &&
1274 	    !calc_seckey(ses)) {
1275 		memcpy(tmp, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
1276 		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
1277 		sec_blob->SessionKey.Length = cpu_to_le16(CIFS_CPHTXT_SIZE);
1278 		sec_blob->SessionKey.MaximumLength =
1279 				cpu_to_le16(CIFS_CPHTXT_SIZE);
1280 		tmp += CIFS_CPHTXT_SIZE;
1281 	} else {
1282 		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
1283 		sec_blob->SessionKey.Length = 0;
1284 		sec_blob->SessionKey.MaximumLength = 0;
1285 	}
1286 
1287 	*buflen = tmp - *pbuffer;
1288 setup_ntlmv2_ret:
1289 	return rc;
1290 }
1291 
1292 enum securityEnum
1293 cifs_select_sectype(struct TCP_Server_Info *server, enum securityEnum requested)
1294 {
1295 	switch (server->negflavor) {
1296 	case CIFS_NEGFLAVOR_EXTENDED:
1297 		switch (requested) {
1298 		case Kerberos:
1299 		case RawNTLMSSP:
1300 			return requested;
1301 		case Unspecified:
1302 			if (server->sec_ntlmssp &&
1303 			    (global_secflags & CIFSSEC_MAY_NTLMSSP))
1304 				return RawNTLMSSP;
1305 			if ((server->sec_kerberos || server->sec_mskerberos) &&
1306 			    (global_secflags & CIFSSEC_MAY_KRB5))
1307 				return Kerberos;
1308 			fallthrough;
1309 		default:
1310 			return Unspecified;
1311 		}
1312 	case CIFS_NEGFLAVOR_UNENCAP:
1313 		switch (requested) {
1314 		case NTLMv2:
1315 			return requested;
1316 		case Unspecified:
1317 			if (global_secflags & CIFSSEC_MAY_NTLMV2)
1318 				return NTLMv2;
1319 			break;
1320 		default:
1321 			break;
1322 		}
1323 		fallthrough;
1324 	default:
1325 		return Unspecified;
1326 	}
1327 }
1328 
1329 struct sess_data {
1330 	unsigned int xid;
1331 	struct cifs_ses *ses;
1332 	struct TCP_Server_Info *server;
1333 	struct nls_table *nls_cp;
1334 	void (*func)(struct sess_data *);
1335 	int result;
1336 
1337 	/* we will send the SMB in three pieces:
1338 	 * a fixed length beginning part, an optional
1339 	 * SPNEGO blob (which can be zero length), and a
1340 	 * last part which will include the strings
1341 	 * and rest of bcc area. This allows us to avoid
1342 	 * a large buffer 17K allocation
1343 	 */
1344 	int buf0_type;
1345 	struct kvec iov[3];
1346 };
1347 
1348 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
1349 static int
1350 sess_alloc_buffer(struct sess_data *sess_data, int wct)
1351 {
1352 	int rc;
1353 	struct cifs_ses *ses = sess_data->ses;
1354 	struct smb_hdr *smb_buf;
1355 
1356 	rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
1357 				  (void **)&smb_buf);
1358 
1359 	if (rc)
1360 		return rc;
1361 
1362 	sess_data->iov[0].iov_base = (char *)smb_buf;
1363 	sess_data->iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;
1364 	/*
1365 	 * This variable will be used to clear the buffer
1366 	 * allocated above in case of any error in the calling function.
1367 	 */
1368 	sess_data->buf0_type = CIFS_SMALL_BUFFER;
1369 
1370 	/* 2000 big enough to fit max user, domain, NOS name etc. */
1371 	sess_data->iov[2].iov_base = kmalloc(2000, GFP_KERNEL);
1372 	if (!sess_data->iov[2].iov_base) {
1373 		rc = -ENOMEM;
1374 		goto out_free_smb_buf;
1375 	}
1376 
1377 	return 0;
1378 
1379 out_free_smb_buf:
1380 	cifs_small_buf_release(smb_buf);
1381 	sess_data->iov[0].iov_base = NULL;
1382 	sess_data->iov[0].iov_len = 0;
1383 	sess_data->buf0_type = CIFS_NO_BUFFER;
1384 	return rc;
1385 }
1386 
1387 static void
1388 sess_free_buffer(struct sess_data *sess_data)
1389 {
1390 	struct kvec *iov = sess_data->iov;
1391 
1392 	/*
1393 	 * Zero the session data before freeing, as it might contain sensitive info (keys, etc).
1394 	 * Note that iov[1] is already freed by caller.
1395 	 */
1396 	if (sess_data->buf0_type != CIFS_NO_BUFFER && iov[0].iov_base)
1397 		memzero_explicit(iov[0].iov_base, iov[0].iov_len);
1398 
1399 	free_rsp_buf(sess_data->buf0_type, iov[0].iov_base);
1400 	sess_data->buf0_type = CIFS_NO_BUFFER;
1401 	kfree_sensitive(iov[2].iov_base);
1402 }
1403 
1404 static int
1405 sess_establish_session(struct sess_data *sess_data)
1406 {
1407 	struct cifs_ses *ses = sess_data->ses;
1408 	struct TCP_Server_Info *server = sess_data->server;
1409 
1410 	cifs_server_lock(server);
1411 	if (!server->session_estab) {
1412 		if (server->sign) {
1413 			server->session_key.response =
1414 				kmemdup(ses->auth_key.response,
1415 				ses->auth_key.len, GFP_KERNEL);
1416 			if (!server->session_key.response) {
1417 				cifs_server_unlock(server);
1418 				return -ENOMEM;
1419 			}
1420 			server->session_key.len =
1421 						ses->auth_key.len;
1422 		}
1423 		server->sequence_number = 0x2;
1424 		server->session_estab = true;
1425 	}
1426 	cifs_server_unlock(server);
1427 
1428 	cifs_dbg(FYI, "CIFS session established successfully\n");
1429 	return 0;
1430 }
1431 
1432 static int
1433 sess_sendreceive(struct sess_data *sess_data)
1434 {
1435 	int rc;
1436 	struct smb_hdr *smb_buf = (struct smb_hdr *) sess_data->iov[0].iov_base;
1437 	__u16 count;
1438 	struct kvec rsp_iov = { NULL, 0 };
1439 
1440 	count = sess_data->iov[1].iov_len + sess_data->iov[2].iov_len;
1441 	be32_add_cpu(&smb_buf->smb_buf_length, count);
1442 	put_bcc(count, smb_buf);
1443 
1444 	rc = SendReceive2(sess_data->xid, sess_data->ses,
1445 			  sess_data->iov, 3 /* num_iovecs */,
1446 			  &sess_data->buf0_type,
1447 			  CIFS_LOG_ERROR, &rsp_iov);
1448 	cifs_small_buf_release(sess_data->iov[0].iov_base);
1449 	memcpy(&sess_data->iov[0], &rsp_iov, sizeof(struct kvec));
1450 
1451 	return rc;
1452 }
1453 
1454 static void
1455 sess_auth_ntlmv2(struct sess_data *sess_data)
1456 {
1457 	int rc = 0;
1458 	struct smb_hdr *smb_buf;
1459 	SESSION_SETUP_ANDX *pSMB;
1460 	char *bcc_ptr;
1461 	struct cifs_ses *ses = sess_data->ses;
1462 	struct TCP_Server_Info *server = sess_data->server;
1463 	__u32 capabilities;
1464 	__u16 bytes_remaining;
1465 
1466 	/* old style NTLM sessionsetup */
1467 	/* wct = 13 */
1468 	rc = sess_alloc_buffer(sess_data, 13);
1469 	if (rc)
1470 		goto out;
1471 
1472 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1473 	bcc_ptr = sess_data->iov[2].iov_base;
1474 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1475 
1476 	pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
1477 
1478 	/* LM2 password would be here if we supported it */
1479 	pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
1480 
1481 	if (ses->user_name != NULL) {
1482 		/* calculate nlmv2 response and session key */
1483 		rc = setup_ntlmv2_rsp(ses, sess_data->nls_cp);
1484 		if (rc) {
1485 			cifs_dbg(VFS, "Error %d during NTLMv2 authentication\n", rc);
1486 			goto out;
1487 		}
1488 
1489 		memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
1490 				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1491 		bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
1492 
1493 		/* set case sensitive password length after tilen may get
1494 		 * assigned, tilen is 0 otherwise.
1495 		 */
1496 		pSMB->req_no_secext.CaseSensitivePasswordLength =
1497 			cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1498 	} else {
1499 		pSMB->req_no_secext.CaseSensitivePasswordLength = 0;
1500 	}
1501 
1502 	if (ses->capabilities & CAP_UNICODE) {
1503 		if (!IS_ALIGNED(sess_data->iov[0].iov_len, 2)) {
1504 			*bcc_ptr = 0;
1505 			bcc_ptr++;
1506 		}
1507 		unicode_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1508 	} else {
1509 		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1510 	}
1511 
1512 
1513 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1514 			(long) sess_data->iov[2].iov_base;
1515 
1516 	rc = sess_sendreceive(sess_data);
1517 	if (rc)
1518 		goto out;
1519 
1520 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1521 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1522 
1523 	if (smb_buf->WordCount != 3) {
1524 		rc = -EIO;
1525 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1526 		goto out;
1527 	}
1528 
1529 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1530 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1531 
1532 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1533 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1534 
1535 	bytes_remaining = get_bcc(smb_buf);
1536 	bcc_ptr = pByteArea(smb_buf);
1537 
1538 	/* BB check if Unicode and decode strings */
1539 	if (bytes_remaining == 0) {
1540 		/* no string area to decode, do nothing */
1541 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1542 		/* unicode string area must be word-aligned */
1543 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1544 			++bcc_ptr;
1545 			--bytes_remaining;
1546 		}
1547 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1548 				      sess_data->nls_cp);
1549 	} else {
1550 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1551 				    sess_data->nls_cp);
1552 	}
1553 
1554 	rc = sess_establish_session(sess_data);
1555 out:
1556 	sess_data->result = rc;
1557 	sess_data->func = NULL;
1558 	sess_free_buffer(sess_data);
1559 	kfree_sensitive(ses->auth_key.response);
1560 	ses->auth_key.response = NULL;
1561 }
1562 
1563 #ifdef CONFIG_CIFS_UPCALL
1564 static void
1565 sess_auth_kerberos(struct sess_data *sess_data)
1566 {
1567 	int rc = 0;
1568 	struct smb_hdr *smb_buf;
1569 	SESSION_SETUP_ANDX *pSMB;
1570 	char *bcc_ptr;
1571 	struct cifs_ses *ses = sess_data->ses;
1572 	struct TCP_Server_Info *server = sess_data->server;
1573 	__u32 capabilities;
1574 	__u16 bytes_remaining;
1575 	struct key *spnego_key = NULL;
1576 	struct cifs_spnego_msg *msg;
1577 	u16 blob_len;
1578 
1579 	/* extended security */
1580 	/* wct = 12 */
1581 	rc = sess_alloc_buffer(sess_data, 12);
1582 	if (rc)
1583 		goto out;
1584 
1585 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1586 	bcc_ptr = sess_data->iov[2].iov_base;
1587 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1588 
1589 	spnego_key = cifs_get_spnego_key(ses, server);
1590 	if (IS_ERR(spnego_key)) {
1591 		rc = PTR_ERR(spnego_key);
1592 		spnego_key = NULL;
1593 		goto out;
1594 	}
1595 
1596 	msg = spnego_key->payload.data[0];
1597 	/*
1598 	 * check version field to make sure that cifs.upcall is
1599 	 * sending us a response in an expected form
1600 	 */
1601 	if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
1602 		cifs_dbg(VFS, "incorrect version of cifs.upcall (expected %d but got %d)\n",
1603 			 CIFS_SPNEGO_UPCALL_VERSION, msg->version);
1604 		rc = -EKEYREJECTED;
1605 		goto out_put_spnego_key;
1606 	}
1607 
1608 	kfree_sensitive(ses->auth_key.response);
1609 	ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
1610 					 GFP_KERNEL);
1611 	if (!ses->auth_key.response) {
1612 		cifs_dbg(VFS, "Kerberos can't allocate (%u bytes) memory\n",
1613 			 msg->sesskey_len);
1614 		rc = -ENOMEM;
1615 		goto out_put_spnego_key;
1616 	}
1617 	ses->auth_key.len = msg->sesskey_len;
1618 
1619 	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
1620 	capabilities |= CAP_EXTENDED_SECURITY;
1621 	pSMB->req.Capabilities = cpu_to_le32(capabilities);
1622 	sess_data->iov[1].iov_base = msg->data + msg->sesskey_len;
1623 	sess_data->iov[1].iov_len = msg->secblob_len;
1624 	pSMB->req.SecurityBlobLength = cpu_to_le16(sess_data->iov[1].iov_len);
1625 
1626 	if (ses->capabilities & CAP_UNICODE) {
1627 		/* unicode strings must be word aligned */
1628 		if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
1629 			*bcc_ptr = 0;
1630 			bcc_ptr++;
1631 		}
1632 		unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1633 		unicode_domain_string(&bcc_ptr, ses, sess_data->nls_cp);
1634 	} else {
1635 		/* BB: is this right? */
1636 		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1637 	}
1638 
1639 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1640 			(long) sess_data->iov[2].iov_base;
1641 
1642 	rc = sess_sendreceive(sess_data);
1643 	if (rc)
1644 		goto out_put_spnego_key;
1645 
1646 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1647 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1648 
1649 	if (smb_buf->WordCount != 4) {
1650 		rc = -EIO;
1651 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1652 		goto out_put_spnego_key;
1653 	}
1654 
1655 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1656 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1657 
1658 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1659 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1660 
1661 	bytes_remaining = get_bcc(smb_buf);
1662 	bcc_ptr = pByteArea(smb_buf);
1663 
1664 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1665 	if (blob_len > bytes_remaining) {
1666 		cifs_dbg(VFS, "bad security blob length %d\n",
1667 				blob_len);
1668 		rc = -EINVAL;
1669 		goto out_put_spnego_key;
1670 	}
1671 	bcc_ptr += blob_len;
1672 	bytes_remaining -= blob_len;
1673 
1674 	/* BB check if Unicode and decode strings */
1675 	if (bytes_remaining == 0) {
1676 		/* no string area to decode, do nothing */
1677 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1678 		/* unicode string area must be word-aligned */
1679 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1680 			++bcc_ptr;
1681 			--bytes_remaining;
1682 		}
1683 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1684 				      sess_data->nls_cp);
1685 	} else {
1686 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1687 				    sess_data->nls_cp);
1688 	}
1689 
1690 	rc = sess_establish_session(sess_data);
1691 out_put_spnego_key:
1692 	key_invalidate(spnego_key);
1693 	key_put(spnego_key);
1694 out:
1695 	sess_data->result = rc;
1696 	sess_data->func = NULL;
1697 	sess_free_buffer(sess_data);
1698 	kfree_sensitive(ses->auth_key.response);
1699 	ses->auth_key.response = NULL;
1700 }
1701 
1702 #endif /* ! CONFIG_CIFS_UPCALL */
1703 
1704 /*
1705  * The required kvec buffers have to be allocated before calling this
1706  * function.
1707  */
1708 static int
1709 _sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
1710 {
1711 	SESSION_SETUP_ANDX *pSMB;
1712 	struct cifs_ses *ses = sess_data->ses;
1713 	struct TCP_Server_Info *server = sess_data->server;
1714 	__u32 capabilities;
1715 	char *bcc_ptr;
1716 
1717 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1718 
1719 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1720 	if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
1721 		cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
1722 		return -ENOSYS;
1723 	}
1724 
1725 	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
1726 	capabilities |= CAP_EXTENDED_SECURITY;
1727 	pSMB->req.Capabilities |= cpu_to_le32(capabilities);
1728 
1729 	bcc_ptr = sess_data->iov[2].iov_base;
1730 	/* unicode strings must be word aligned */
1731 	if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
1732 		*bcc_ptr = 0;
1733 		bcc_ptr++;
1734 	}
1735 	unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1736 
1737 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1738 					(long) sess_data->iov[2].iov_base;
1739 
1740 	return 0;
1741 }
1742 
1743 static void
1744 sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data);
1745 
1746 static void
1747 sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
1748 {
1749 	int rc;
1750 	struct smb_hdr *smb_buf;
1751 	SESSION_SETUP_ANDX *pSMB;
1752 	struct cifs_ses *ses = sess_data->ses;
1753 	struct TCP_Server_Info *server = sess_data->server;
1754 	__u16 bytes_remaining;
1755 	char *bcc_ptr;
1756 	unsigned char *ntlmsspblob = NULL;
1757 	u16 blob_len;
1758 
1759 	cifs_dbg(FYI, "rawntlmssp session setup negotiate phase\n");
1760 
1761 	/*
1762 	 * if memory allocation is successful, caller of this function
1763 	 * frees it.
1764 	 */
1765 	ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
1766 	if (!ses->ntlmssp) {
1767 		rc = -ENOMEM;
1768 		goto out;
1769 	}
1770 	ses->ntlmssp->sesskey_per_smbsess = false;
1771 
1772 	/* wct = 12 */
1773 	rc = sess_alloc_buffer(sess_data, 12);
1774 	if (rc)
1775 		goto out;
1776 
1777 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1778 
1779 	/* Build security blob before we assemble the request */
1780 	rc = build_ntlmssp_negotiate_blob(&ntlmsspblob,
1781 				     &blob_len, ses, server,
1782 				     sess_data->nls_cp);
1783 	if (rc)
1784 		goto out_free_ntlmsspblob;
1785 
1786 	sess_data->iov[1].iov_len = blob_len;
1787 	sess_data->iov[1].iov_base = ntlmsspblob;
1788 	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
1789 
1790 	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
1791 	if (rc)
1792 		goto out_free_ntlmsspblob;
1793 
1794 	rc = sess_sendreceive(sess_data);
1795 
1796 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1797 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1798 
1799 	/* If true, rc here is expected and not an error */
1800 	if (sess_data->buf0_type != CIFS_NO_BUFFER &&
1801 	    smb_buf->Status.CifsError ==
1802 			cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))
1803 		rc = 0;
1804 
1805 	if (rc)
1806 		goto out_free_ntlmsspblob;
1807 
1808 	cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n");
1809 
1810 	if (smb_buf->WordCount != 4) {
1811 		rc = -EIO;
1812 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1813 		goto out_free_ntlmsspblob;
1814 	}
1815 
1816 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1817 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1818 
1819 	bytes_remaining = get_bcc(smb_buf);
1820 	bcc_ptr = pByteArea(smb_buf);
1821 
1822 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1823 	if (blob_len > bytes_remaining) {
1824 		cifs_dbg(VFS, "bad security blob length %d\n",
1825 				blob_len);
1826 		rc = -EINVAL;
1827 		goto out_free_ntlmsspblob;
1828 	}
1829 
1830 	rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
1831 
1832 out_free_ntlmsspblob:
1833 	kfree_sensitive(ntlmsspblob);
1834 out:
1835 	sess_free_buffer(sess_data);
1836 
1837 	if (!rc) {
1838 		sess_data->func = sess_auth_rawntlmssp_authenticate;
1839 		return;
1840 	}
1841 
1842 	/* Else error. Cleanup */
1843 	kfree_sensitive(ses->auth_key.response);
1844 	ses->auth_key.response = NULL;
1845 	kfree_sensitive(ses->ntlmssp);
1846 	ses->ntlmssp = NULL;
1847 
1848 	sess_data->func = NULL;
1849 	sess_data->result = rc;
1850 }
1851 
1852 static void
1853 sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
1854 {
1855 	int rc;
1856 	struct smb_hdr *smb_buf;
1857 	SESSION_SETUP_ANDX *pSMB;
1858 	struct cifs_ses *ses = sess_data->ses;
1859 	struct TCP_Server_Info *server = sess_data->server;
1860 	__u16 bytes_remaining;
1861 	char *bcc_ptr;
1862 	unsigned char *ntlmsspblob = NULL;
1863 	u16 blob_len;
1864 
1865 	cifs_dbg(FYI, "rawntlmssp session setup authenticate phase\n");
1866 
1867 	/* wct = 12 */
1868 	rc = sess_alloc_buffer(sess_data, 12);
1869 	if (rc)
1870 		goto out;
1871 
1872 	/* Build security blob before we assemble the request */
1873 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1874 	smb_buf = (struct smb_hdr *)pSMB;
1875 	rc = build_ntlmssp_auth_blob(&ntlmsspblob,
1876 					&blob_len, ses, server,
1877 					sess_data->nls_cp);
1878 	if (rc)
1879 		goto out_free_ntlmsspblob;
1880 	sess_data->iov[1].iov_len = blob_len;
1881 	sess_data->iov[1].iov_base = ntlmsspblob;
1882 	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
1883 	/*
1884 	 * Make sure that we tell the server that we are using
1885 	 * the uid that it just gave us back on the response
1886 	 * (challenge)
1887 	 */
1888 	smb_buf->Uid = ses->Suid;
1889 
1890 	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
1891 	if (rc)
1892 		goto out_free_ntlmsspblob;
1893 
1894 	rc = sess_sendreceive(sess_data);
1895 	if (rc)
1896 		goto out_free_ntlmsspblob;
1897 
1898 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1899 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1900 	if (smb_buf->WordCount != 4) {
1901 		rc = -EIO;
1902 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1903 		goto out_free_ntlmsspblob;
1904 	}
1905 
1906 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1907 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1908 
1909 	if (ses->Suid != smb_buf->Uid) {
1910 		ses->Suid = smb_buf->Uid;
1911 		cifs_dbg(FYI, "UID changed! new UID = %llu\n", ses->Suid);
1912 	}
1913 
1914 	bytes_remaining = get_bcc(smb_buf);
1915 	bcc_ptr = pByteArea(smb_buf);
1916 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1917 	if (blob_len > bytes_remaining) {
1918 		cifs_dbg(VFS, "bad security blob length %d\n",
1919 				blob_len);
1920 		rc = -EINVAL;
1921 		goto out_free_ntlmsspblob;
1922 	}
1923 	bcc_ptr += blob_len;
1924 	bytes_remaining -= blob_len;
1925 
1926 
1927 	/* BB check if Unicode and decode strings */
1928 	if (bytes_remaining == 0) {
1929 		/* no string area to decode, do nothing */
1930 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1931 		/* unicode string area must be word-aligned */
1932 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1933 			++bcc_ptr;
1934 			--bytes_remaining;
1935 		}
1936 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1937 				      sess_data->nls_cp);
1938 	} else {
1939 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1940 				    sess_data->nls_cp);
1941 	}
1942 
1943 out_free_ntlmsspblob:
1944 	kfree_sensitive(ntlmsspblob);
1945 out:
1946 	sess_free_buffer(sess_data);
1947 
1948 	if (!rc)
1949 		rc = sess_establish_session(sess_data);
1950 
1951 	/* Cleanup */
1952 	kfree_sensitive(ses->auth_key.response);
1953 	ses->auth_key.response = NULL;
1954 	kfree_sensitive(ses->ntlmssp);
1955 	ses->ntlmssp = NULL;
1956 
1957 	sess_data->func = NULL;
1958 	sess_data->result = rc;
1959 }
1960 
1961 static int select_sec(struct sess_data *sess_data)
1962 {
1963 	int type;
1964 	struct cifs_ses *ses = sess_data->ses;
1965 	struct TCP_Server_Info *server = sess_data->server;
1966 
1967 	type = cifs_select_sectype(server, ses->sectype);
1968 	cifs_dbg(FYI, "sess setup type %d\n", type);
1969 	if (type == Unspecified) {
1970 		cifs_dbg(VFS, "Unable to select appropriate authentication method!\n");
1971 		return -EINVAL;
1972 	}
1973 
1974 	switch (type) {
1975 	case NTLMv2:
1976 		sess_data->func = sess_auth_ntlmv2;
1977 		break;
1978 	case Kerberos:
1979 #ifdef CONFIG_CIFS_UPCALL
1980 		sess_data->func = sess_auth_kerberos;
1981 		break;
1982 #else
1983 		cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
1984 		return -ENOSYS;
1985 #endif /* CONFIG_CIFS_UPCALL */
1986 	case RawNTLMSSP:
1987 		sess_data->func = sess_auth_rawntlmssp_negotiate;
1988 		break;
1989 	default:
1990 		cifs_dbg(VFS, "secType %d not supported!\n", type);
1991 		return -ENOSYS;
1992 	}
1993 
1994 	return 0;
1995 }
1996 
1997 int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
1998 		   struct TCP_Server_Info *server,
1999 		   const struct nls_table *nls_cp)
2000 {
2001 	int rc = 0;
2002 	struct sess_data *sess_data;
2003 
2004 	if (ses == NULL) {
2005 		WARN(1, "%s: ses == NULL!", __func__);
2006 		return -EINVAL;
2007 	}
2008 
2009 	sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
2010 	if (!sess_data)
2011 		return -ENOMEM;
2012 
2013 	sess_data->xid = xid;
2014 	sess_data->ses = ses;
2015 	sess_data->server = server;
2016 	sess_data->buf0_type = CIFS_NO_BUFFER;
2017 	sess_data->nls_cp = (struct nls_table *) nls_cp;
2018 
2019 	rc = select_sec(sess_data);
2020 	if (rc)
2021 		goto out;
2022 
2023 	while (sess_data->func)
2024 		sess_data->func(sess_data);
2025 
2026 	/* Store result before we free sess_data */
2027 	rc = sess_data->result;
2028 
2029 out:
2030 	kfree_sensitive(sess_data);
2031 	return rc;
2032 }
2033 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
2034