xref: /linux/fs/smb/client/sess.c (revision 8faabc041a001140564f718dabe37753e88b37fa)
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 	/* 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
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
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 void
119 cifs_chan_set_need_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;
126 
127 	set_bit(chan_index, &ses->chans_need_reconnect);
128 	cifs_dbg(FYI, "Set reconnect bitmask for chan %u; now 0x%lx\n",
129 		 chan_index, ses->chans_need_reconnect);
130 }
131 
132 void
133 cifs_chan_clear_need_reconnect(struct cifs_ses *ses,
134 			       struct TCP_Server_Info *server)
135 {
136 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
137 
138 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
139 		return;
140 
141 	clear_bit(chan_index, &ses->chans_need_reconnect);
142 	cifs_dbg(FYI, "Cleared reconnect bitmask for chan %u; now 0x%lx\n",
143 		 chan_index, ses->chans_need_reconnect);
144 }
145 
146 bool
147 cifs_chan_needs_reconnect(struct cifs_ses *ses,
148 			  struct TCP_Server_Info *server)
149 {
150 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
151 
152 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
153 		return true;	/* err on the safer side */
154 
155 	return CIFS_CHAN_NEEDS_RECONNECT(ses, chan_index);
156 }
157 
158 bool
159 cifs_chan_is_iface_active(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 ses->chans[chan_index].iface &&
168 		ses->chans[chan_index].iface->is_active;
169 }
170 
171 /* returns number of channels added */
172 int cifs_try_adding_channels(struct cifs_ses *ses)
173 {
174 	struct TCP_Server_Info *server = ses->server;
175 	int old_chan_count, new_chan_count;
176 	int left;
177 	int rc = 0;
178 	int tries = 0;
179 	size_t iface_weight = 0, iface_min_speed = 0;
180 	struct cifs_server_iface *iface = NULL, *niface = NULL;
181 	struct cifs_server_iface *last_iface = NULL;
182 
183 	spin_lock(&ses->chan_lock);
184 
185 	new_chan_count = old_chan_count = ses->chan_count;
186 	left = ses->chan_max - ses->chan_count;
187 
188 	if (left <= 0) {
189 		spin_unlock(&ses->chan_lock);
190 		cifs_dbg(FYI,
191 			 "ses already at max_channels (%zu), nothing to open\n",
192 			 ses->chan_max);
193 		return 0;
194 	}
195 
196 	if (server->dialect < SMB30_PROT_ID) {
197 		spin_unlock(&ses->chan_lock);
198 		cifs_dbg(VFS, "multichannel is not supported on this protocol version, use 3.0 or above\n");
199 		return 0;
200 	}
201 
202 	if (!(server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
203 		spin_unlock(&ses->chan_lock);
204 		cifs_server_dbg(VFS, "no multichannel support\n");
205 		return 0;
206 	}
207 	spin_unlock(&ses->chan_lock);
208 
209 	while (left > 0) {
210 
211 		tries++;
212 		if (tries > 3*ses->chan_max) {
213 			cifs_dbg(VFS, "too many channel open attempts (%d channels left to open)\n",
214 				 left);
215 			break;
216 		}
217 
218 		spin_lock(&ses->iface_lock);
219 		if (!ses->iface_count) {
220 			spin_unlock(&ses->iface_lock);
221 			cifs_dbg(ONCE, "server %s does not advertise interfaces\n",
222 				      ses->server->hostname);
223 			break;
224 		}
225 
226 		if (!iface)
227 			iface = list_first_entry(&ses->iface_list, struct cifs_server_iface,
228 						 iface_head);
229 		last_iface = list_last_entry(&ses->iface_list, struct cifs_server_iface,
230 					     iface_head);
231 		iface_min_speed = last_iface->speed;
232 
233 		list_for_each_entry_safe_from(iface, niface, &ses->iface_list,
234 				    iface_head) {
235 			/* do not mix rdma and non-rdma interfaces */
236 			if (iface->rdma_capable != ses->server->rdma)
237 				continue;
238 
239 			/* skip ifaces that are unusable */
240 			if (!iface->is_active ||
241 			    (is_ses_using_iface(ses, iface) &&
242 			     !iface->rss_capable))
243 				continue;
244 
245 			/* check if we already allocated enough channels */
246 			iface_weight = iface->speed / iface_min_speed;
247 
248 			if (iface->weight_fulfilled >= iface_weight)
249 				continue;
250 
251 			/* take ref before unlock */
252 			kref_get(&iface->refcount);
253 
254 			spin_unlock(&ses->iface_lock);
255 			rc = cifs_ses_add_channel(ses, iface);
256 			spin_lock(&ses->iface_lock);
257 
258 			if (rc) {
259 				cifs_dbg(VFS, "failed to open extra channel on iface:%pIS rc=%d\n",
260 					 &iface->sockaddr,
261 					 rc);
262 				kref_put(&iface->refcount, release_iface);
263 				/* failure to add chan should increase weight */
264 				iface->weight_fulfilled++;
265 				continue;
266 			}
267 
268 			iface->num_channels++;
269 			iface->weight_fulfilled++;
270 			cifs_dbg(VFS, "successfully opened new channel on iface:%pIS\n",
271 				 &iface->sockaddr);
272 			break;
273 		}
274 
275 		/* reached end of list. reset weight_fulfilled and start over */
276 		if (list_entry_is_head(iface, &ses->iface_list, iface_head)) {
277 			list_for_each_entry(iface, &ses->iface_list, iface_head)
278 				iface->weight_fulfilled = 0;
279 			spin_unlock(&ses->iface_lock);
280 			iface = NULL;
281 			continue;
282 		}
283 		spin_unlock(&ses->iface_lock);
284 
285 		left--;
286 		new_chan_count++;
287 	}
288 
289 	return new_chan_count - old_chan_count;
290 }
291 
292 /*
293  * called when multichannel is disabled by the server.
294  * this always gets called from smb2_reconnect
295  * and cannot get called in parallel threads.
296  */
297 void
298 cifs_disable_secondary_channels(struct cifs_ses *ses)
299 {
300 	int i, chan_count;
301 	struct TCP_Server_Info *server;
302 	struct cifs_server_iface *iface;
303 
304 	spin_lock(&ses->chan_lock);
305 	chan_count = ses->chan_count;
306 	if (chan_count == 1)
307 		goto done;
308 
309 	ses->chan_count = 1;
310 
311 	/* for all secondary channels reset the need reconnect bit */
312 	ses->chans_need_reconnect &= 1;
313 
314 	for (i = 1; i < chan_count; i++) {
315 		iface = ses->chans[i].iface;
316 		server = ses->chans[i].server;
317 
318 		/*
319 		 * remove these references first, since we need to unlock
320 		 * the chan_lock here, since iface_lock is a higher lock
321 		 */
322 		ses->chans[i].iface = NULL;
323 		ses->chans[i].server = NULL;
324 		spin_unlock(&ses->chan_lock);
325 
326 		if (iface) {
327 			spin_lock(&ses->iface_lock);
328 			iface->num_channels--;
329 			if (iface->weight_fulfilled)
330 				iface->weight_fulfilled--;
331 			kref_put(&iface->refcount, release_iface);
332 			spin_unlock(&ses->iface_lock);
333 		}
334 
335 		if (server) {
336 			if (!server->terminate) {
337 				server->terminate = true;
338 				cifs_signal_cifsd_for_reconnect(server, false);
339 			}
340 			cifs_put_tcp_session(server, false);
341 		}
342 
343 		spin_lock(&ses->chan_lock);
344 	}
345 
346 done:
347 	spin_unlock(&ses->chan_lock);
348 }
349 
350 /* update the iface for the channel if necessary. */
351 void
352 cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
353 {
354 	unsigned int chan_index;
355 	size_t iface_weight = 0, iface_min_speed = 0;
356 	struct cifs_server_iface *iface = NULL;
357 	struct cifs_server_iface *old_iface = NULL;
358 	struct cifs_server_iface *last_iface = NULL;
359 	struct sockaddr_storage ss;
360 
361 	spin_lock(&ses->chan_lock);
362 	chan_index = cifs_ses_get_chan_index(ses, server);
363 	if (chan_index == CIFS_INVAL_CHAN_INDEX) {
364 		spin_unlock(&ses->chan_lock);
365 		return;
366 	}
367 
368 	if (ses->chans[chan_index].iface) {
369 		old_iface = ses->chans[chan_index].iface;
370 		if (old_iface->is_active) {
371 			spin_unlock(&ses->chan_lock);
372 			return;
373 		}
374 	}
375 	spin_unlock(&ses->chan_lock);
376 
377 	spin_lock(&server->srv_lock);
378 	ss = server->dstaddr;
379 	spin_unlock(&server->srv_lock);
380 
381 	spin_lock(&ses->iface_lock);
382 	if (!ses->iface_count) {
383 		spin_unlock(&ses->iface_lock);
384 		cifs_dbg(ONCE, "server %s does not advertise interfaces\n", ses->server->hostname);
385 		return;
386 	}
387 
388 	last_iface = list_last_entry(&ses->iface_list, struct cifs_server_iface,
389 				     iface_head);
390 	iface_min_speed = last_iface->speed;
391 
392 	/* then look for a new one */
393 	list_for_each_entry(iface, &ses->iface_list, iface_head) {
394 		if (!chan_index) {
395 			/* if we're trying to get the updated iface for primary channel */
396 			if (!cifs_match_ipaddr((struct sockaddr *) &ss,
397 					       (struct sockaddr *) &iface->sockaddr))
398 				continue;
399 
400 			kref_get(&iface->refcount);
401 			break;
402 		}
403 
404 		/* do not mix rdma and non-rdma interfaces */
405 		if (iface->rdma_capable != server->rdma)
406 			continue;
407 
408 		if (!iface->is_active ||
409 		    (is_ses_using_iface(ses, iface) &&
410 		     !iface->rss_capable)) {
411 			continue;
412 		}
413 
414 		/* check if we already allocated enough channels */
415 		iface_weight = iface->speed / iface_min_speed;
416 
417 		if (iface->weight_fulfilled >= iface_weight)
418 			continue;
419 
420 		kref_get(&iface->refcount);
421 		break;
422 	}
423 
424 	if (list_entry_is_head(iface, &ses->iface_list, iface_head)) {
425 		iface = NULL;
426 		cifs_dbg(FYI, "unable to find a suitable iface\n");
427 	}
428 
429 	if (!iface) {
430 		if (!chan_index)
431 			cifs_dbg(FYI, "unable to get the interface matching: %pIS\n",
432 				 &ss);
433 		else {
434 			cifs_dbg(FYI, "unable to find another interface to replace: %pIS\n",
435 				 &old_iface->sockaddr);
436 		}
437 
438 		spin_unlock(&ses->iface_lock);
439 		return;
440 	}
441 
442 	/* now drop the ref to the current iface */
443 	if (old_iface) {
444 		cifs_dbg(FYI, "replacing iface: %pIS with %pIS\n",
445 			 &old_iface->sockaddr,
446 			 &iface->sockaddr);
447 
448 		old_iface->num_channels--;
449 		if (old_iface->weight_fulfilled)
450 			old_iface->weight_fulfilled--;
451 		iface->num_channels++;
452 		iface->weight_fulfilled++;
453 
454 		kref_put(&old_iface->refcount, release_iface);
455 	} else if (!chan_index) {
456 		/* special case: update interface for primary channel */
457 		cifs_dbg(FYI, "referencing primary channel iface: %pIS\n",
458 			 &iface->sockaddr);
459 		iface->num_channels++;
460 		iface->weight_fulfilled++;
461 	}
462 	spin_unlock(&ses->iface_lock);
463 
464 	spin_lock(&ses->chan_lock);
465 	chan_index = cifs_ses_get_chan_index(ses, server);
466 	if (chan_index == CIFS_INVAL_CHAN_INDEX) {
467 		spin_unlock(&ses->chan_lock);
468 		return;
469 	}
470 
471 	ses->chans[chan_index].iface = iface;
472 	spin_unlock(&ses->chan_lock);
473 }
474 
475 static int
476 cifs_ses_add_channel(struct cifs_ses *ses,
477 		     struct cifs_server_iface *iface)
478 {
479 	struct TCP_Server_Info *chan_server;
480 	struct cifs_chan *chan;
481 	struct smb3_fs_context *ctx;
482 	static const char unc_fmt[] = "\\%s\\foo";
483 	struct sockaddr_in *ipv4 = (struct sockaddr_in *)&iface->sockaddr;
484 	struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&iface->sockaddr;
485 	size_t len;
486 	int rc;
487 	unsigned int xid = get_xid();
488 
489 	if (iface->sockaddr.ss_family == AF_INET)
490 		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI4)\n",
491 			 ses, iface->speed, str_yes_no(iface->rdma_capable),
492 			 &ipv4->sin_addr);
493 	else
494 		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI6)\n",
495 			 ses, iface->speed, str_yes_no(iface->rdma_capable),
496 			 &ipv6->sin6_addr);
497 
498 	/*
499 	 * Setup a ctx with mostly the same info as the existing
500 	 * session and overwrite it with the requested iface data.
501 	 *
502 	 * We need to setup at least the fields used for negprot and
503 	 * sesssetup.
504 	 *
505 	 * We only need the ctx here, so we can reuse memory from
506 	 * the session and server without caring about memory
507 	 * management.
508 	 */
509 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
510 	if (!ctx) {
511 		rc = -ENOMEM;
512 		goto out_free_xid;
513 	}
514 
515 	/* Always make new connection for now (TODO?) */
516 	ctx->nosharesock = true;
517 
518 	/* Auth */
519 	ctx->domainauto = ses->domainAuto;
520 	ctx->domainname = ses->domainName;
521 
522 	/* no hostname for extra channels */
523 	ctx->server_hostname = "";
524 
525 	ctx->username = ses->user_name;
526 	ctx->password = ses->password;
527 	ctx->sectype = ses->sectype;
528 	ctx->sign = ses->sign;
529 
530 	/* UNC and paths */
531 	/* XXX: Use ses->server->hostname? */
532 	len = sizeof(unc_fmt) + SERVER_NAME_LEN_WITH_NULL;
533 	ctx->UNC = kzalloc(len, GFP_KERNEL);
534 	if (!ctx->UNC) {
535 		rc = -ENOMEM;
536 		goto out_free_ctx;
537 	}
538 	scnprintf(ctx->UNC, len, unc_fmt, ses->ip_addr);
539 	ctx->prepath = "";
540 
541 	/* Reuse same version as master connection */
542 	ctx->vals = ses->server->vals;
543 	ctx->ops = ses->server->ops;
544 
545 	ctx->noblocksnd = ses->server->noblocksnd;
546 	ctx->noautotune = ses->server->noautotune;
547 	ctx->sockopt_tcp_nodelay = ses->server->tcp_nodelay;
548 	ctx->echo_interval = ses->server->echo_interval / HZ;
549 	ctx->max_credits = ses->server->max_credits;
550 
551 	/*
552 	 * This will be used for encoding/decoding user/domain/pw
553 	 * during sess setup auth.
554 	 */
555 	ctx->local_nls = ses->local_nls;
556 
557 	/* Use RDMA if possible */
558 	ctx->rdma = iface->rdma_capable;
559 	memcpy(&ctx->dstaddr, &iface->sockaddr, sizeof(ctx->dstaddr));
560 
561 	/* reuse master con client guid */
562 	memcpy(&ctx->client_guid, ses->server->client_guid,
563 	       sizeof(ctx->client_guid));
564 	ctx->use_client_guid = true;
565 
566 	chan_server = cifs_get_tcp_session(ctx, ses->server);
567 
568 	spin_lock(&ses->chan_lock);
569 	chan = &ses->chans[ses->chan_count];
570 	chan->server = chan_server;
571 	if (IS_ERR(chan->server)) {
572 		rc = PTR_ERR(chan->server);
573 		chan->server = NULL;
574 		spin_unlock(&ses->chan_lock);
575 		goto out;
576 	}
577 	chan->iface = iface;
578 	ses->chan_count++;
579 	atomic_set(&ses->chan_seq, 0);
580 
581 	/* Mark this channel as needing connect/setup */
582 	cifs_chan_set_need_reconnect(ses, chan->server);
583 
584 	spin_unlock(&ses->chan_lock);
585 
586 	mutex_lock(&ses->session_mutex);
587 	/*
588 	 * We need to allocate the server crypto now as we will need
589 	 * to sign packets before we generate the channel signing key
590 	 * (we sign with the session key)
591 	 */
592 	rc = smb311_crypto_shash_allocate(chan->server);
593 	if (rc) {
594 		cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
595 		mutex_unlock(&ses->session_mutex);
596 		goto out;
597 	}
598 
599 	rc = cifs_negotiate_protocol(xid, ses, chan->server);
600 	if (!rc)
601 		rc = cifs_setup_session(xid, ses, chan->server, ses->local_nls);
602 
603 	mutex_unlock(&ses->session_mutex);
604 
605 out:
606 	if (rc && chan->server) {
607 		cifs_put_tcp_session(chan->server, 0);
608 
609 		spin_lock(&ses->chan_lock);
610 
611 		/* we rely on all bits beyond chan_count to be clear */
612 		cifs_chan_clear_need_reconnect(ses, chan->server);
613 		ses->chan_count--;
614 		/*
615 		 * chan_count should never reach 0 as at least the primary
616 		 * channel is always allocated
617 		 */
618 		WARN_ON(ses->chan_count < 1);
619 		spin_unlock(&ses->chan_lock);
620 	}
621 
622 	kfree(ctx->UNC);
623 out_free_ctx:
624 	kfree(ctx);
625 out_free_xid:
626 	free_xid(xid);
627 	return rc;
628 }
629 
630 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
631 static __u32 cifs_ssetup_hdr(struct cifs_ses *ses,
632 			     struct TCP_Server_Info *server,
633 			     SESSION_SETUP_ANDX *pSMB)
634 {
635 	__u32 capabilities = 0;
636 
637 	/* init fields common to all four types of SessSetup */
638 	/* Note that offsets for first seven fields in req struct are same  */
639 	/*	in CIFS Specs so does not matter which of 3 forms of struct */
640 	/*	that we use in next few lines                               */
641 	/* Note that header is initialized to zero in header_assemble */
642 	pSMB->req.AndXCommand = 0xFF;
643 	pSMB->req.MaxBufferSize = cpu_to_le16(min_t(u32,
644 					CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4,
645 					USHRT_MAX));
646 	pSMB->req.MaxMpxCount = cpu_to_le16(server->maxReq);
647 	pSMB->req.VcNumber = cpu_to_le16(1);
648 
649 	/* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
650 
651 	/* BB verify whether signing required on neg or just auth frame (and NTLM case) */
652 
653 	capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
654 			CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
655 
656 	if (server->sign)
657 		pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
658 
659 	if (ses->capabilities & CAP_UNICODE) {
660 		pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
661 		capabilities |= CAP_UNICODE;
662 	}
663 	if (ses->capabilities & CAP_STATUS32) {
664 		pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
665 		capabilities |= CAP_STATUS32;
666 	}
667 	if (ses->capabilities & CAP_DFS) {
668 		pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
669 		capabilities |= CAP_DFS;
670 	}
671 	if (ses->capabilities & CAP_UNIX)
672 		capabilities |= CAP_UNIX;
673 
674 	return capabilities;
675 }
676 
677 static void
678 unicode_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
679 {
680 	char *bcc_ptr = *pbcc_area;
681 	int bytes_ret = 0;
682 
683 	/* Copy OS version */
684 	bytes_ret = cifs_strtoUTF16((__le16 *)bcc_ptr, "Linux version ", 32,
685 				    nls_cp);
686 	bcc_ptr += 2 * bytes_ret;
687 	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, init_utsname()->release,
688 				    32, nls_cp);
689 	bcc_ptr += 2 * bytes_ret;
690 	bcc_ptr += 2; /* trailing null */
691 
692 	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
693 				    32, nls_cp);
694 	bcc_ptr += 2 * bytes_ret;
695 	bcc_ptr += 2; /* trailing null */
696 
697 	*pbcc_area = bcc_ptr;
698 }
699 
700 static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
701 				   const struct nls_table *nls_cp)
702 {
703 	char *bcc_ptr = *pbcc_area;
704 	int bytes_ret = 0;
705 
706 	/* copy domain */
707 	if (ses->domainName == NULL) {
708 		/*
709 		 * Sending null domain better than using a bogus domain name (as
710 		 * we did briefly in 2.6.18) since server will use its default
711 		 */
712 		*bcc_ptr = 0;
713 		*(bcc_ptr+1) = 0;
714 		bytes_ret = 0;
715 	} else
716 		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
717 					    CIFS_MAX_DOMAINNAME_LEN, nls_cp);
718 	bcc_ptr += 2 * bytes_ret;
719 	bcc_ptr += 2;  /* account for null terminator */
720 
721 	*pbcc_area = bcc_ptr;
722 }
723 
724 static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
725 				   const struct nls_table *nls_cp)
726 {
727 	char *bcc_ptr = *pbcc_area;
728 	int bytes_ret = 0;
729 
730 	/* BB FIXME add check that strings less than 335 or will need to send as arrays */
731 
732 	/* copy user */
733 	if (ses->user_name == NULL) {
734 		/* null user mount */
735 		*bcc_ptr = 0;
736 		*(bcc_ptr+1) = 0;
737 	} else {
738 		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->user_name,
739 					    CIFS_MAX_USERNAME_LEN, nls_cp);
740 	}
741 	bcc_ptr += 2 * bytes_ret;
742 	bcc_ptr += 2; /* account for null termination */
743 
744 	unicode_domain_string(&bcc_ptr, ses, nls_cp);
745 	unicode_oslm_strings(&bcc_ptr, nls_cp);
746 
747 	*pbcc_area = bcc_ptr;
748 }
749 
750 static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
751 				 const struct nls_table *nls_cp)
752 {
753 	char *bcc_ptr = *pbcc_area;
754 	int len;
755 
756 	/* copy user */
757 	/* BB what about null user mounts - check that we do this BB */
758 	/* copy user */
759 	if (ses->user_name != NULL) {
760 		len = strscpy(bcc_ptr, ses->user_name, CIFS_MAX_USERNAME_LEN);
761 		if (WARN_ON_ONCE(len < 0))
762 			len = CIFS_MAX_USERNAME_LEN - 1;
763 		bcc_ptr += len;
764 	}
765 	/* else null user mount */
766 	*bcc_ptr = 0;
767 	bcc_ptr++; /* account for null termination */
768 
769 	/* copy domain */
770 	if (ses->domainName != NULL) {
771 		len = strscpy(bcc_ptr, ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
772 		if (WARN_ON_ONCE(len < 0))
773 			len = CIFS_MAX_DOMAINNAME_LEN - 1;
774 		bcc_ptr += len;
775 	} /* else we send a null domain name so server will default to its own domain */
776 	*bcc_ptr = 0;
777 	bcc_ptr++;
778 
779 	/* BB check for overflow here */
780 
781 	strcpy(bcc_ptr, "Linux version ");
782 	bcc_ptr += strlen("Linux version ");
783 	strcpy(bcc_ptr, init_utsname()->release);
784 	bcc_ptr += strlen(init_utsname()->release) + 1;
785 
786 	strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
787 	bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;
788 
789 	*pbcc_area = bcc_ptr;
790 }
791 
792 static void
793 decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifs_ses *ses,
794 		      const struct nls_table *nls_cp)
795 {
796 	int len;
797 	char *data = *pbcc_area;
798 
799 	cifs_dbg(FYI, "bleft %d\n", bleft);
800 
801 	kfree(ses->serverOS);
802 	ses->serverOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
803 	cifs_dbg(FYI, "serverOS=%s\n", ses->serverOS);
804 	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
805 	data += len;
806 	bleft -= len;
807 	if (bleft <= 0)
808 		return;
809 
810 	kfree(ses->serverNOS);
811 	ses->serverNOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
812 	cifs_dbg(FYI, "serverNOS=%s\n", ses->serverNOS);
813 	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
814 	data += len;
815 	bleft -= len;
816 	if (bleft <= 0)
817 		return;
818 
819 	kfree(ses->serverDomain);
820 	ses->serverDomain = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
821 	cifs_dbg(FYI, "serverDomain=%s\n", ses->serverDomain);
822 
823 	return;
824 }
825 
826 static void decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
827 				struct cifs_ses *ses,
828 				const struct nls_table *nls_cp)
829 {
830 	int len;
831 	char *bcc_ptr = *pbcc_area;
832 
833 	cifs_dbg(FYI, "decode sessetup ascii. bleft %d\n", bleft);
834 
835 	len = strnlen(bcc_ptr, bleft);
836 	if (len >= bleft)
837 		return;
838 
839 	kfree(ses->serverOS);
840 
841 	ses->serverOS = kmalloc(len + 1, GFP_KERNEL);
842 	if (ses->serverOS) {
843 		memcpy(ses->serverOS, bcc_ptr, len);
844 		ses->serverOS[len] = 0;
845 		if (strncmp(ses->serverOS, "OS/2", 4) == 0)
846 			cifs_dbg(FYI, "OS/2 server\n");
847 	}
848 
849 	bcc_ptr += len + 1;
850 	bleft -= len + 1;
851 
852 	len = strnlen(bcc_ptr, bleft);
853 	if (len >= bleft)
854 		return;
855 
856 	kfree(ses->serverNOS);
857 
858 	ses->serverNOS = kmalloc(len + 1, GFP_KERNEL);
859 	if (ses->serverNOS) {
860 		memcpy(ses->serverNOS, bcc_ptr, len);
861 		ses->serverNOS[len] = 0;
862 	}
863 
864 	bcc_ptr += len + 1;
865 	bleft -= len + 1;
866 
867 	len = strnlen(bcc_ptr, bleft);
868 	if (len > bleft)
869 		return;
870 
871 	/*
872 	 * No domain field in LANMAN case. Domain is
873 	 * returned by old servers in the SMB negprot response
874 	 *
875 	 * BB For newer servers which do not support Unicode,
876 	 * but thus do return domain here, we could add parsing
877 	 * for it later, but it is not very important
878 	 */
879 	cifs_dbg(FYI, "ascii: bytes left %d\n", bleft);
880 }
881 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
882 
883 int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
884 				    struct cifs_ses *ses)
885 {
886 	unsigned int tioffset; /* challenge message target info area */
887 	unsigned int tilen; /* challenge message target info area length  */
888 	CHALLENGE_MESSAGE *pblob = (CHALLENGE_MESSAGE *)bcc_ptr;
889 	__u32 server_flags;
890 
891 	if (blob_len < sizeof(CHALLENGE_MESSAGE)) {
892 		cifs_dbg(VFS, "challenge blob len %d too small\n", blob_len);
893 		return -EINVAL;
894 	}
895 
896 	if (memcmp(pblob->Signature, "NTLMSSP", 8)) {
897 		cifs_dbg(VFS, "blob signature incorrect %s\n",
898 			 pblob->Signature);
899 		return -EINVAL;
900 	}
901 	if (pblob->MessageType != NtLmChallenge) {
902 		cifs_dbg(VFS, "Incorrect message type %d\n",
903 			 pblob->MessageType);
904 		return -EINVAL;
905 	}
906 
907 	server_flags = le32_to_cpu(pblob->NegotiateFlags);
908 	cifs_dbg(FYI, "%s: negotiate=0x%08x challenge=0x%08x\n", __func__,
909 		 ses->ntlmssp->client_flags, server_flags);
910 
911 	if ((ses->ntlmssp->client_flags & (NTLMSSP_NEGOTIATE_SEAL | NTLMSSP_NEGOTIATE_SIGN)) &&
912 	    (!(server_flags & NTLMSSP_NEGOTIATE_56) && !(server_flags & NTLMSSP_NEGOTIATE_128))) {
913 		cifs_dbg(VFS, "%s: requested signing/encryption but server did not return either 56-bit or 128-bit session key size\n",
914 			 __func__);
915 		return -EINVAL;
916 	}
917 	if (!(server_flags & NTLMSSP_NEGOTIATE_NTLM) && !(server_flags & NTLMSSP_NEGOTIATE_EXTENDED_SEC)) {
918 		cifs_dbg(VFS, "%s: server does not seem to support either NTLMv1 or NTLMv2\n", __func__);
919 		return -EINVAL;
920 	}
921 	if (ses->server->sign && !(server_flags & NTLMSSP_NEGOTIATE_SIGN)) {
922 		cifs_dbg(VFS, "%s: forced packet signing but server does not seem to support it\n",
923 			 __func__);
924 		return -EOPNOTSUPP;
925 	}
926 	if ((ses->ntlmssp->client_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
927 	    !(server_flags & NTLMSSP_NEGOTIATE_KEY_XCH))
928 		pr_warn_once("%s: authentication has been weakened as server does not support key exchange\n",
929 			     __func__);
930 
931 	ses->ntlmssp->server_flags = server_flags;
932 
933 	memcpy(ses->ntlmssp->cryptkey, pblob->Challenge, CIFS_CRYPTO_KEY_SIZE);
934 	/*
935 	 * In particular we can examine sign flags
936 	 *
937 	 * BB spec says that if AvId field of MsvAvTimestamp is populated then
938 	 * we must set the MIC field of the AUTHENTICATE_MESSAGE
939 	 */
940 
941 	tioffset = le32_to_cpu(pblob->TargetInfoArray.BufferOffset);
942 	tilen = le16_to_cpu(pblob->TargetInfoArray.Length);
943 	if (tioffset > blob_len || tioffset + tilen > blob_len) {
944 		cifs_dbg(VFS, "tioffset + tilen too high %u + %u\n",
945 			 tioffset, tilen);
946 		return -EINVAL;
947 	}
948 	if (tilen) {
949 		kfree_sensitive(ses->auth_key.response);
950 		ses->auth_key.response = kmemdup(bcc_ptr + tioffset, tilen,
951 						 GFP_KERNEL);
952 		if (!ses->auth_key.response) {
953 			cifs_dbg(VFS, "Challenge target info alloc failure\n");
954 			return -ENOMEM;
955 		}
956 		ses->auth_key.len = tilen;
957 	}
958 
959 	return 0;
960 }
961 
962 static int size_of_ntlmssp_blob(struct cifs_ses *ses, int base_size)
963 {
964 	int sz = base_size + ses->auth_key.len
965 		- CIFS_SESS_KEY_SIZE + CIFS_CPHTXT_SIZE + 2;
966 
967 	if (ses->domainName)
968 		sz += sizeof(__le16) * strnlen(ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
969 	else
970 		sz += sizeof(__le16);
971 
972 	if (ses->user_name)
973 		sz += sizeof(__le16) * strnlen(ses->user_name, CIFS_MAX_USERNAME_LEN);
974 	else
975 		sz += sizeof(__le16);
976 
977 	if (ses->workstation_name[0])
978 		sz += sizeof(__le16) * strnlen(ses->workstation_name,
979 					       ntlmssp_workstation_name_size(ses));
980 	else
981 		sz += sizeof(__le16);
982 
983 	return sz;
984 }
985 
986 static inline void cifs_security_buffer_from_str(SECURITY_BUFFER *pbuf,
987 						 char *str_value,
988 						 int str_length,
989 						 unsigned char *pstart,
990 						 unsigned char **pcur,
991 						 const struct nls_table *nls_cp)
992 {
993 	unsigned char *tmp = pstart;
994 	int len;
995 
996 	if (!pbuf)
997 		return;
998 
999 	if (!pcur)
1000 		pcur = &tmp;
1001 
1002 	if (!str_value) {
1003 		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
1004 		pbuf->Length = 0;
1005 		pbuf->MaximumLength = 0;
1006 		*pcur += sizeof(__le16);
1007 	} else {
1008 		len = cifs_strtoUTF16((__le16 *)*pcur,
1009 				      str_value,
1010 				      str_length,
1011 				      nls_cp);
1012 		len *= sizeof(__le16);
1013 		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
1014 		pbuf->Length = cpu_to_le16(len);
1015 		pbuf->MaximumLength = cpu_to_le16(len);
1016 		*pcur += len;
1017 	}
1018 }
1019 
1020 /* BB Move to ntlmssp.c eventually */
1021 
1022 int build_ntlmssp_negotiate_blob(unsigned char **pbuffer,
1023 				 u16 *buflen,
1024 				 struct cifs_ses *ses,
1025 				 struct TCP_Server_Info *server,
1026 				 const struct nls_table *nls_cp)
1027 {
1028 	int rc = 0;
1029 	NEGOTIATE_MESSAGE *sec_blob;
1030 	__u32 flags;
1031 	unsigned char *tmp;
1032 	int len;
1033 
1034 	len = size_of_ntlmssp_blob(ses, sizeof(NEGOTIATE_MESSAGE));
1035 	*pbuffer = kmalloc(len, GFP_KERNEL);
1036 	if (!*pbuffer) {
1037 		rc = -ENOMEM;
1038 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1039 		*buflen = 0;
1040 		goto setup_ntlm_neg_ret;
1041 	}
1042 	sec_blob = (NEGOTIATE_MESSAGE *)*pbuffer;
1043 
1044 	memset(*pbuffer, 0, sizeof(NEGOTIATE_MESSAGE));
1045 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1046 	sec_blob->MessageType = NtLmNegotiate;
1047 
1048 	/* BB is NTLMV2 session security format easier to use here? */
1049 	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
1050 		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
1051 		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
1052 		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
1053 		NTLMSSP_NEGOTIATE_SIGN;
1054 	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
1055 		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
1056 
1057 	tmp = *pbuffer + sizeof(NEGOTIATE_MESSAGE);
1058 	ses->ntlmssp->client_flags = flags;
1059 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1060 
1061 	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
1062 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1063 				      NULL,
1064 				      CIFS_MAX_DOMAINNAME_LEN,
1065 				      *pbuffer, &tmp,
1066 				      nls_cp);
1067 
1068 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1069 				      NULL,
1070 				      CIFS_MAX_WORKSTATION_LEN,
1071 				      *pbuffer, &tmp,
1072 				      nls_cp);
1073 
1074 	*buflen = tmp - *pbuffer;
1075 setup_ntlm_neg_ret:
1076 	return rc;
1077 }
1078 
1079 /*
1080  * Build ntlmssp blob with additional fields, such as version,
1081  * supported by modern servers. For safety limit to SMB3 or later
1082  * See notes in MS-NLMP Section 2.2.2.1 e.g.
1083  */
1084 int build_ntlmssp_smb3_negotiate_blob(unsigned char **pbuffer,
1085 				 u16 *buflen,
1086 				 struct cifs_ses *ses,
1087 				 struct TCP_Server_Info *server,
1088 				 const struct nls_table *nls_cp)
1089 {
1090 	int rc = 0;
1091 	struct negotiate_message *sec_blob;
1092 	__u32 flags;
1093 	unsigned char *tmp;
1094 	int len;
1095 
1096 	len = size_of_ntlmssp_blob(ses, sizeof(struct negotiate_message));
1097 	*pbuffer = kmalloc(len, GFP_KERNEL);
1098 	if (!*pbuffer) {
1099 		rc = -ENOMEM;
1100 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1101 		*buflen = 0;
1102 		goto setup_ntlm_smb3_neg_ret;
1103 	}
1104 	sec_blob = (struct negotiate_message *)*pbuffer;
1105 
1106 	memset(*pbuffer, 0, sizeof(struct negotiate_message));
1107 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1108 	sec_blob->MessageType = NtLmNegotiate;
1109 
1110 	/* BB is NTLMV2 session security format easier to use here? */
1111 	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
1112 		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
1113 		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
1114 		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
1115 		NTLMSSP_NEGOTIATE_SIGN | NTLMSSP_NEGOTIATE_VERSION;
1116 	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
1117 		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
1118 
1119 	sec_blob->Version.ProductMajorVersion = LINUX_VERSION_MAJOR;
1120 	sec_blob->Version.ProductMinorVersion = LINUX_VERSION_PATCHLEVEL;
1121 	sec_blob->Version.ProductBuild = cpu_to_le16(SMB3_PRODUCT_BUILD);
1122 	sec_blob->Version.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
1123 
1124 	tmp = *pbuffer + sizeof(struct negotiate_message);
1125 	ses->ntlmssp->client_flags = flags;
1126 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1127 
1128 	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
1129 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1130 				      NULL,
1131 				      CIFS_MAX_DOMAINNAME_LEN,
1132 				      *pbuffer, &tmp,
1133 				      nls_cp);
1134 
1135 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1136 				      NULL,
1137 				      CIFS_MAX_WORKSTATION_LEN,
1138 				      *pbuffer, &tmp,
1139 				      nls_cp);
1140 
1141 	*buflen = tmp - *pbuffer;
1142 setup_ntlm_smb3_neg_ret:
1143 	return rc;
1144 }
1145 
1146 
1147 /* See MS-NLMP 2.2.1.3 */
1148 int build_ntlmssp_auth_blob(unsigned char **pbuffer,
1149 					u16 *buflen,
1150 				   struct cifs_ses *ses,
1151 				   struct TCP_Server_Info *server,
1152 				   const struct nls_table *nls_cp)
1153 {
1154 	int rc;
1155 	AUTHENTICATE_MESSAGE *sec_blob;
1156 	__u32 flags;
1157 	unsigned char *tmp;
1158 	int len;
1159 
1160 	rc = setup_ntlmv2_rsp(ses, nls_cp);
1161 	if (rc) {
1162 		cifs_dbg(VFS, "Error %d during NTLMSSP authentication\n", rc);
1163 		*buflen = 0;
1164 		goto setup_ntlmv2_ret;
1165 	}
1166 
1167 	len = size_of_ntlmssp_blob(ses, sizeof(AUTHENTICATE_MESSAGE));
1168 	*pbuffer = kmalloc(len, GFP_KERNEL);
1169 	if (!*pbuffer) {
1170 		rc = -ENOMEM;
1171 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1172 		*buflen = 0;
1173 		goto setup_ntlmv2_ret;
1174 	}
1175 	sec_blob = (AUTHENTICATE_MESSAGE *)*pbuffer;
1176 
1177 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1178 	sec_blob->MessageType = NtLmAuthenticate;
1179 
1180 	/* send version information in ntlmssp authenticate also */
1181 	flags = ses->ntlmssp->server_flags | NTLMSSP_REQUEST_TARGET |
1182 		NTLMSSP_NEGOTIATE_TARGET_INFO | NTLMSSP_NEGOTIATE_VERSION |
1183 		NTLMSSP_NEGOTIATE_WORKSTATION_SUPPLIED;
1184 
1185 	sec_blob->Version.ProductMajorVersion = LINUX_VERSION_MAJOR;
1186 	sec_blob->Version.ProductMinorVersion = LINUX_VERSION_PATCHLEVEL;
1187 	sec_blob->Version.ProductBuild = cpu_to_le16(SMB3_PRODUCT_BUILD);
1188 	sec_blob->Version.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
1189 
1190 	tmp = *pbuffer + sizeof(AUTHENTICATE_MESSAGE);
1191 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1192 
1193 	sec_blob->LmChallengeResponse.BufferOffset =
1194 				cpu_to_le32(sizeof(AUTHENTICATE_MESSAGE));
1195 	sec_blob->LmChallengeResponse.Length = 0;
1196 	sec_blob->LmChallengeResponse.MaximumLength = 0;
1197 
1198 	sec_blob->NtChallengeResponse.BufferOffset =
1199 				cpu_to_le32(tmp - *pbuffer);
1200 	if (ses->user_name != NULL) {
1201 		memcpy(tmp, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
1202 				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1203 		tmp += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
1204 
1205 		sec_blob->NtChallengeResponse.Length =
1206 				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1207 		sec_blob->NtChallengeResponse.MaximumLength =
1208 				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1209 	} else {
1210 		/*
1211 		 * don't send an NT Response for anonymous access
1212 		 */
1213 		sec_blob->NtChallengeResponse.Length = 0;
1214 		sec_blob->NtChallengeResponse.MaximumLength = 0;
1215 	}
1216 
1217 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1218 				      ses->domainName,
1219 				      CIFS_MAX_DOMAINNAME_LEN,
1220 				      *pbuffer, &tmp,
1221 				      nls_cp);
1222 
1223 	cifs_security_buffer_from_str(&sec_blob->UserName,
1224 				      ses->user_name,
1225 				      CIFS_MAX_USERNAME_LEN,
1226 				      *pbuffer, &tmp,
1227 				      nls_cp);
1228 
1229 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1230 				      ses->workstation_name,
1231 				      ntlmssp_workstation_name_size(ses),
1232 				      *pbuffer, &tmp,
1233 				      nls_cp);
1234 
1235 	if ((ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
1236 	    (!ses->server->session_estab || ses->ntlmssp->sesskey_per_smbsess) &&
1237 	    !calc_seckey(ses)) {
1238 		memcpy(tmp, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
1239 		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
1240 		sec_blob->SessionKey.Length = cpu_to_le16(CIFS_CPHTXT_SIZE);
1241 		sec_blob->SessionKey.MaximumLength =
1242 				cpu_to_le16(CIFS_CPHTXT_SIZE);
1243 		tmp += CIFS_CPHTXT_SIZE;
1244 	} else {
1245 		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
1246 		sec_blob->SessionKey.Length = 0;
1247 		sec_blob->SessionKey.MaximumLength = 0;
1248 	}
1249 
1250 	*buflen = tmp - *pbuffer;
1251 setup_ntlmv2_ret:
1252 	return rc;
1253 }
1254 
1255 enum securityEnum
1256 cifs_select_sectype(struct TCP_Server_Info *server, enum securityEnum requested)
1257 {
1258 	switch (server->negflavor) {
1259 	case CIFS_NEGFLAVOR_EXTENDED:
1260 		switch (requested) {
1261 		case Kerberos:
1262 		case RawNTLMSSP:
1263 			return requested;
1264 		case Unspecified:
1265 			if (server->sec_ntlmssp &&
1266 			    (global_secflags & CIFSSEC_MAY_NTLMSSP))
1267 				return RawNTLMSSP;
1268 			if ((server->sec_kerberos || server->sec_mskerberos) &&
1269 			    (global_secflags & CIFSSEC_MAY_KRB5))
1270 				return Kerberos;
1271 			fallthrough;
1272 		default:
1273 			return Unspecified;
1274 		}
1275 	case CIFS_NEGFLAVOR_UNENCAP:
1276 		switch (requested) {
1277 		case NTLMv2:
1278 			return requested;
1279 		case Unspecified:
1280 			if (global_secflags & CIFSSEC_MAY_NTLMV2)
1281 				return NTLMv2;
1282 			break;
1283 		default:
1284 			break;
1285 		}
1286 		fallthrough;
1287 	default:
1288 		return Unspecified;
1289 	}
1290 }
1291 
1292 struct sess_data {
1293 	unsigned int xid;
1294 	struct cifs_ses *ses;
1295 	struct TCP_Server_Info *server;
1296 	struct nls_table *nls_cp;
1297 	void (*func)(struct sess_data *);
1298 	int result;
1299 
1300 	/* we will send the SMB in three pieces:
1301 	 * a fixed length beginning part, an optional
1302 	 * SPNEGO blob (which can be zero length), and a
1303 	 * last part which will include the strings
1304 	 * and rest of bcc area. This allows us to avoid
1305 	 * a large buffer 17K allocation
1306 	 */
1307 	int buf0_type;
1308 	struct kvec iov[3];
1309 };
1310 
1311 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
1312 static int
1313 sess_alloc_buffer(struct sess_data *sess_data, int wct)
1314 {
1315 	int rc;
1316 	struct cifs_ses *ses = sess_data->ses;
1317 	struct smb_hdr *smb_buf;
1318 
1319 	rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
1320 				  (void **)&smb_buf);
1321 
1322 	if (rc)
1323 		return rc;
1324 
1325 	sess_data->iov[0].iov_base = (char *)smb_buf;
1326 	sess_data->iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;
1327 	/*
1328 	 * This variable will be used to clear the buffer
1329 	 * allocated above in case of any error in the calling function.
1330 	 */
1331 	sess_data->buf0_type = CIFS_SMALL_BUFFER;
1332 
1333 	/* 2000 big enough to fit max user, domain, NOS name etc. */
1334 	sess_data->iov[2].iov_base = kmalloc(2000, GFP_KERNEL);
1335 	if (!sess_data->iov[2].iov_base) {
1336 		rc = -ENOMEM;
1337 		goto out_free_smb_buf;
1338 	}
1339 
1340 	return 0;
1341 
1342 out_free_smb_buf:
1343 	cifs_small_buf_release(smb_buf);
1344 	sess_data->iov[0].iov_base = NULL;
1345 	sess_data->iov[0].iov_len = 0;
1346 	sess_data->buf0_type = CIFS_NO_BUFFER;
1347 	return rc;
1348 }
1349 
1350 static void
1351 sess_free_buffer(struct sess_data *sess_data)
1352 {
1353 	struct kvec *iov = sess_data->iov;
1354 
1355 	/*
1356 	 * Zero the session data before freeing, as it might contain sensitive info (keys, etc).
1357 	 * Note that iov[1] is already freed by caller.
1358 	 */
1359 	if (sess_data->buf0_type != CIFS_NO_BUFFER && iov[0].iov_base)
1360 		memzero_explicit(iov[0].iov_base, iov[0].iov_len);
1361 
1362 	free_rsp_buf(sess_data->buf0_type, iov[0].iov_base);
1363 	sess_data->buf0_type = CIFS_NO_BUFFER;
1364 	kfree_sensitive(iov[2].iov_base);
1365 }
1366 
1367 static int
1368 sess_establish_session(struct sess_data *sess_data)
1369 {
1370 	struct cifs_ses *ses = sess_data->ses;
1371 	struct TCP_Server_Info *server = sess_data->server;
1372 
1373 	cifs_server_lock(server);
1374 	if (!server->session_estab) {
1375 		if (server->sign) {
1376 			server->session_key.response =
1377 				kmemdup(ses->auth_key.response,
1378 				ses->auth_key.len, GFP_KERNEL);
1379 			if (!server->session_key.response) {
1380 				cifs_server_unlock(server);
1381 				return -ENOMEM;
1382 			}
1383 			server->session_key.len =
1384 						ses->auth_key.len;
1385 		}
1386 		server->sequence_number = 0x2;
1387 		server->session_estab = true;
1388 	}
1389 	cifs_server_unlock(server);
1390 
1391 	cifs_dbg(FYI, "CIFS session established successfully\n");
1392 	return 0;
1393 }
1394 
1395 static int
1396 sess_sendreceive(struct sess_data *sess_data)
1397 {
1398 	int rc;
1399 	struct smb_hdr *smb_buf = (struct smb_hdr *) sess_data->iov[0].iov_base;
1400 	__u16 count;
1401 	struct kvec rsp_iov = { NULL, 0 };
1402 
1403 	count = sess_data->iov[1].iov_len + sess_data->iov[2].iov_len;
1404 	be32_add_cpu(&smb_buf->smb_buf_length, count);
1405 	put_bcc(count, smb_buf);
1406 
1407 	rc = SendReceive2(sess_data->xid, sess_data->ses,
1408 			  sess_data->iov, 3 /* num_iovecs */,
1409 			  &sess_data->buf0_type,
1410 			  CIFS_LOG_ERROR, &rsp_iov);
1411 	cifs_small_buf_release(sess_data->iov[0].iov_base);
1412 	memcpy(&sess_data->iov[0], &rsp_iov, sizeof(struct kvec));
1413 
1414 	return rc;
1415 }
1416 
1417 static void
1418 sess_auth_ntlmv2(struct sess_data *sess_data)
1419 {
1420 	int rc = 0;
1421 	struct smb_hdr *smb_buf;
1422 	SESSION_SETUP_ANDX *pSMB;
1423 	char *bcc_ptr;
1424 	struct cifs_ses *ses = sess_data->ses;
1425 	struct TCP_Server_Info *server = sess_data->server;
1426 	__u32 capabilities;
1427 	__u16 bytes_remaining;
1428 
1429 	/* old style NTLM sessionsetup */
1430 	/* wct = 13 */
1431 	rc = sess_alloc_buffer(sess_data, 13);
1432 	if (rc)
1433 		goto out;
1434 
1435 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1436 	bcc_ptr = sess_data->iov[2].iov_base;
1437 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1438 
1439 	pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
1440 
1441 	/* LM2 password would be here if we supported it */
1442 	pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
1443 
1444 	if (ses->user_name != NULL) {
1445 		/* calculate nlmv2 response and session key */
1446 		rc = setup_ntlmv2_rsp(ses, sess_data->nls_cp);
1447 		if (rc) {
1448 			cifs_dbg(VFS, "Error %d during NTLMv2 authentication\n", rc);
1449 			goto out;
1450 		}
1451 
1452 		memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
1453 				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1454 		bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
1455 
1456 		/* set case sensitive password length after tilen may get
1457 		 * assigned, tilen is 0 otherwise.
1458 		 */
1459 		pSMB->req_no_secext.CaseSensitivePasswordLength =
1460 			cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1461 	} else {
1462 		pSMB->req_no_secext.CaseSensitivePasswordLength = 0;
1463 	}
1464 
1465 	if (ses->capabilities & CAP_UNICODE) {
1466 		if (!IS_ALIGNED(sess_data->iov[0].iov_len, 2)) {
1467 			*bcc_ptr = 0;
1468 			bcc_ptr++;
1469 		}
1470 		unicode_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1471 	} else {
1472 		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1473 	}
1474 
1475 
1476 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1477 			(long) sess_data->iov[2].iov_base;
1478 
1479 	rc = sess_sendreceive(sess_data);
1480 	if (rc)
1481 		goto out;
1482 
1483 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1484 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1485 
1486 	if (smb_buf->WordCount != 3) {
1487 		rc = -EIO;
1488 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1489 		goto out;
1490 	}
1491 
1492 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1493 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1494 
1495 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1496 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1497 
1498 	bytes_remaining = get_bcc(smb_buf);
1499 	bcc_ptr = pByteArea(smb_buf);
1500 
1501 	/* BB check if Unicode and decode strings */
1502 	if (bytes_remaining == 0) {
1503 		/* no string area to decode, do nothing */
1504 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1505 		/* unicode string area must be word-aligned */
1506 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1507 			++bcc_ptr;
1508 			--bytes_remaining;
1509 		}
1510 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1511 				      sess_data->nls_cp);
1512 	} else {
1513 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1514 				    sess_data->nls_cp);
1515 	}
1516 
1517 	rc = sess_establish_session(sess_data);
1518 out:
1519 	sess_data->result = rc;
1520 	sess_data->func = NULL;
1521 	sess_free_buffer(sess_data);
1522 	kfree_sensitive(ses->auth_key.response);
1523 	ses->auth_key.response = NULL;
1524 }
1525 
1526 #ifdef CONFIG_CIFS_UPCALL
1527 static void
1528 sess_auth_kerberos(struct sess_data *sess_data)
1529 {
1530 	int rc = 0;
1531 	struct smb_hdr *smb_buf;
1532 	SESSION_SETUP_ANDX *pSMB;
1533 	char *bcc_ptr;
1534 	struct cifs_ses *ses = sess_data->ses;
1535 	struct TCP_Server_Info *server = sess_data->server;
1536 	__u32 capabilities;
1537 	__u16 bytes_remaining;
1538 	struct key *spnego_key = NULL;
1539 	struct cifs_spnego_msg *msg;
1540 	u16 blob_len;
1541 
1542 	/* extended security */
1543 	/* wct = 12 */
1544 	rc = sess_alloc_buffer(sess_data, 12);
1545 	if (rc)
1546 		goto out;
1547 
1548 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1549 	bcc_ptr = sess_data->iov[2].iov_base;
1550 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1551 
1552 	spnego_key = cifs_get_spnego_key(ses, server);
1553 	if (IS_ERR(spnego_key)) {
1554 		rc = PTR_ERR(spnego_key);
1555 		spnego_key = NULL;
1556 		goto out;
1557 	}
1558 
1559 	msg = spnego_key->payload.data[0];
1560 	/*
1561 	 * check version field to make sure that cifs.upcall is
1562 	 * sending us a response in an expected form
1563 	 */
1564 	if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
1565 		cifs_dbg(VFS, "incorrect version of cifs.upcall (expected %d but got %d)\n",
1566 			 CIFS_SPNEGO_UPCALL_VERSION, msg->version);
1567 		rc = -EKEYREJECTED;
1568 		goto out_put_spnego_key;
1569 	}
1570 
1571 	kfree_sensitive(ses->auth_key.response);
1572 	ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
1573 					 GFP_KERNEL);
1574 	if (!ses->auth_key.response) {
1575 		cifs_dbg(VFS, "Kerberos can't allocate (%u bytes) memory\n",
1576 			 msg->sesskey_len);
1577 		rc = -ENOMEM;
1578 		goto out_put_spnego_key;
1579 	}
1580 	ses->auth_key.len = msg->sesskey_len;
1581 
1582 	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
1583 	capabilities |= CAP_EXTENDED_SECURITY;
1584 	pSMB->req.Capabilities = cpu_to_le32(capabilities);
1585 	sess_data->iov[1].iov_base = msg->data + msg->sesskey_len;
1586 	sess_data->iov[1].iov_len = msg->secblob_len;
1587 	pSMB->req.SecurityBlobLength = cpu_to_le16(sess_data->iov[1].iov_len);
1588 
1589 	if (ses->capabilities & CAP_UNICODE) {
1590 		/* unicode strings must be word aligned */
1591 		if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
1592 			*bcc_ptr = 0;
1593 			bcc_ptr++;
1594 		}
1595 		unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1596 		unicode_domain_string(&bcc_ptr, ses, sess_data->nls_cp);
1597 	} else {
1598 		/* BB: is this right? */
1599 		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1600 	}
1601 
1602 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1603 			(long) sess_data->iov[2].iov_base;
1604 
1605 	rc = sess_sendreceive(sess_data);
1606 	if (rc)
1607 		goto out_put_spnego_key;
1608 
1609 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1610 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1611 
1612 	if (smb_buf->WordCount != 4) {
1613 		rc = -EIO;
1614 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1615 		goto out_put_spnego_key;
1616 	}
1617 
1618 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1619 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1620 
1621 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1622 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1623 
1624 	bytes_remaining = get_bcc(smb_buf);
1625 	bcc_ptr = pByteArea(smb_buf);
1626 
1627 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1628 	if (blob_len > bytes_remaining) {
1629 		cifs_dbg(VFS, "bad security blob length %d\n",
1630 				blob_len);
1631 		rc = -EINVAL;
1632 		goto out_put_spnego_key;
1633 	}
1634 	bcc_ptr += blob_len;
1635 	bytes_remaining -= blob_len;
1636 
1637 	/* BB check if Unicode and decode strings */
1638 	if (bytes_remaining == 0) {
1639 		/* no string area to decode, do nothing */
1640 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1641 		/* unicode string area must be word-aligned */
1642 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1643 			++bcc_ptr;
1644 			--bytes_remaining;
1645 		}
1646 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1647 				      sess_data->nls_cp);
1648 	} else {
1649 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1650 				    sess_data->nls_cp);
1651 	}
1652 
1653 	rc = sess_establish_session(sess_data);
1654 out_put_spnego_key:
1655 	key_invalidate(spnego_key);
1656 	key_put(spnego_key);
1657 out:
1658 	sess_data->result = rc;
1659 	sess_data->func = NULL;
1660 	sess_free_buffer(sess_data);
1661 	kfree_sensitive(ses->auth_key.response);
1662 	ses->auth_key.response = NULL;
1663 }
1664 
1665 #endif /* ! CONFIG_CIFS_UPCALL */
1666 
1667 /*
1668  * The required kvec buffers have to be allocated before calling this
1669  * function.
1670  */
1671 static int
1672 _sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
1673 {
1674 	SESSION_SETUP_ANDX *pSMB;
1675 	struct cifs_ses *ses = sess_data->ses;
1676 	struct TCP_Server_Info *server = sess_data->server;
1677 	__u32 capabilities;
1678 	char *bcc_ptr;
1679 
1680 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1681 
1682 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1683 	if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
1684 		cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
1685 		return -ENOSYS;
1686 	}
1687 
1688 	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
1689 	capabilities |= CAP_EXTENDED_SECURITY;
1690 	pSMB->req.Capabilities |= cpu_to_le32(capabilities);
1691 
1692 	bcc_ptr = sess_data->iov[2].iov_base;
1693 	/* unicode strings must be word aligned */
1694 	if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
1695 		*bcc_ptr = 0;
1696 		bcc_ptr++;
1697 	}
1698 	unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1699 
1700 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1701 					(long) sess_data->iov[2].iov_base;
1702 
1703 	return 0;
1704 }
1705 
1706 static void
1707 sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data);
1708 
1709 static void
1710 sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
1711 {
1712 	int rc;
1713 	struct smb_hdr *smb_buf;
1714 	SESSION_SETUP_ANDX *pSMB;
1715 	struct cifs_ses *ses = sess_data->ses;
1716 	struct TCP_Server_Info *server = sess_data->server;
1717 	__u16 bytes_remaining;
1718 	char *bcc_ptr;
1719 	unsigned char *ntlmsspblob = NULL;
1720 	u16 blob_len;
1721 
1722 	cifs_dbg(FYI, "rawntlmssp session setup negotiate phase\n");
1723 
1724 	/*
1725 	 * if memory allocation is successful, caller of this function
1726 	 * frees it.
1727 	 */
1728 	ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
1729 	if (!ses->ntlmssp) {
1730 		rc = -ENOMEM;
1731 		goto out;
1732 	}
1733 	ses->ntlmssp->sesskey_per_smbsess = false;
1734 
1735 	/* wct = 12 */
1736 	rc = sess_alloc_buffer(sess_data, 12);
1737 	if (rc)
1738 		goto out;
1739 
1740 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1741 
1742 	/* Build security blob before we assemble the request */
1743 	rc = build_ntlmssp_negotiate_blob(&ntlmsspblob,
1744 				     &blob_len, ses, server,
1745 				     sess_data->nls_cp);
1746 	if (rc)
1747 		goto out_free_ntlmsspblob;
1748 
1749 	sess_data->iov[1].iov_len = blob_len;
1750 	sess_data->iov[1].iov_base = ntlmsspblob;
1751 	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
1752 
1753 	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
1754 	if (rc)
1755 		goto out_free_ntlmsspblob;
1756 
1757 	rc = sess_sendreceive(sess_data);
1758 
1759 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1760 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1761 
1762 	/* If true, rc here is expected and not an error */
1763 	if (sess_data->buf0_type != CIFS_NO_BUFFER &&
1764 	    smb_buf->Status.CifsError ==
1765 			cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))
1766 		rc = 0;
1767 
1768 	if (rc)
1769 		goto out_free_ntlmsspblob;
1770 
1771 	cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n");
1772 
1773 	if (smb_buf->WordCount != 4) {
1774 		rc = -EIO;
1775 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1776 		goto out_free_ntlmsspblob;
1777 	}
1778 
1779 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1780 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1781 
1782 	bytes_remaining = get_bcc(smb_buf);
1783 	bcc_ptr = pByteArea(smb_buf);
1784 
1785 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1786 	if (blob_len > bytes_remaining) {
1787 		cifs_dbg(VFS, "bad security blob length %d\n",
1788 				blob_len);
1789 		rc = -EINVAL;
1790 		goto out_free_ntlmsspblob;
1791 	}
1792 
1793 	rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
1794 
1795 out_free_ntlmsspblob:
1796 	kfree_sensitive(ntlmsspblob);
1797 out:
1798 	sess_free_buffer(sess_data);
1799 
1800 	if (!rc) {
1801 		sess_data->func = sess_auth_rawntlmssp_authenticate;
1802 		return;
1803 	}
1804 
1805 	/* Else error. Cleanup */
1806 	kfree_sensitive(ses->auth_key.response);
1807 	ses->auth_key.response = NULL;
1808 	kfree_sensitive(ses->ntlmssp);
1809 	ses->ntlmssp = NULL;
1810 
1811 	sess_data->func = NULL;
1812 	sess_data->result = rc;
1813 }
1814 
1815 static void
1816 sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
1817 {
1818 	int rc;
1819 	struct smb_hdr *smb_buf;
1820 	SESSION_SETUP_ANDX *pSMB;
1821 	struct cifs_ses *ses = sess_data->ses;
1822 	struct TCP_Server_Info *server = sess_data->server;
1823 	__u16 bytes_remaining;
1824 	char *bcc_ptr;
1825 	unsigned char *ntlmsspblob = NULL;
1826 	u16 blob_len;
1827 
1828 	cifs_dbg(FYI, "rawntlmssp session setup authenticate phase\n");
1829 
1830 	/* wct = 12 */
1831 	rc = sess_alloc_buffer(sess_data, 12);
1832 	if (rc)
1833 		goto out;
1834 
1835 	/* Build security blob before we assemble the request */
1836 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1837 	smb_buf = (struct smb_hdr *)pSMB;
1838 	rc = build_ntlmssp_auth_blob(&ntlmsspblob,
1839 					&blob_len, ses, server,
1840 					sess_data->nls_cp);
1841 	if (rc)
1842 		goto out_free_ntlmsspblob;
1843 	sess_data->iov[1].iov_len = blob_len;
1844 	sess_data->iov[1].iov_base = ntlmsspblob;
1845 	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
1846 	/*
1847 	 * Make sure that we tell the server that we are using
1848 	 * the uid that it just gave us back on the response
1849 	 * (challenge)
1850 	 */
1851 	smb_buf->Uid = ses->Suid;
1852 
1853 	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
1854 	if (rc)
1855 		goto out_free_ntlmsspblob;
1856 
1857 	rc = sess_sendreceive(sess_data);
1858 	if (rc)
1859 		goto out_free_ntlmsspblob;
1860 
1861 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1862 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1863 	if (smb_buf->WordCount != 4) {
1864 		rc = -EIO;
1865 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1866 		goto out_free_ntlmsspblob;
1867 	}
1868 
1869 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1870 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1871 
1872 	if (ses->Suid != smb_buf->Uid) {
1873 		ses->Suid = smb_buf->Uid;
1874 		cifs_dbg(FYI, "UID changed! new UID = %llu\n", ses->Suid);
1875 	}
1876 
1877 	bytes_remaining = get_bcc(smb_buf);
1878 	bcc_ptr = pByteArea(smb_buf);
1879 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1880 	if (blob_len > bytes_remaining) {
1881 		cifs_dbg(VFS, "bad security blob length %d\n",
1882 				blob_len);
1883 		rc = -EINVAL;
1884 		goto out_free_ntlmsspblob;
1885 	}
1886 	bcc_ptr += blob_len;
1887 	bytes_remaining -= blob_len;
1888 
1889 
1890 	/* BB check if Unicode and decode strings */
1891 	if (bytes_remaining == 0) {
1892 		/* no string area to decode, do nothing */
1893 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1894 		/* unicode string area must be word-aligned */
1895 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1896 			++bcc_ptr;
1897 			--bytes_remaining;
1898 		}
1899 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1900 				      sess_data->nls_cp);
1901 	} else {
1902 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1903 				    sess_data->nls_cp);
1904 	}
1905 
1906 out_free_ntlmsspblob:
1907 	kfree_sensitive(ntlmsspblob);
1908 out:
1909 	sess_free_buffer(sess_data);
1910 
1911 	if (!rc)
1912 		rc = sess_establish_session(sess_data);
1913 
1914 	/* Cleanup */
1915 	kfree_sensitive(ses->auth_key.response);
1916 	ses->auth_key.response = NULL;
1917 	kfree_sensitive(ses->ntlmssp);
1918 	ses->ntlmssp = NULL;
1919 
1920 	sess_data->func = NULL;
1921 	sess_data->result = rc;
1922 }
1923 
1924 static int select_sec(struct sess_data *sess_data)
1925 {
1926 	int type;
1927 	struct cifs_ses *ses = sess_data->ses;
1928 	struct TCP_Server_Info *server = sess_data->server;
1929 
1930 	type = cifs_select_sectype(server, ses->sectype);
1931 	cifs_dbg(FYI, "sess setup type %d\n", type);
1932 	if (type == Unspecified) {
1933 		cifs_dbg(VFS, "Unable to select appropriate authentication method!\n");
1934 		return -EINVAL;
1935 	}
1936 
1937 	switch (type) {
1938 	case NTLMv2:
1939 		sess_data->func = sess_auth_ntlmv2;
1940 		break;
1941 	case Kerberos:
1942 #ifdef CONFIG_CIFS_UPCALL
1943 		sess_data->func = sess_auth_kerberos;
1944 		break;
1945 #else
1946 		cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
1947 		return -ENOSYS;
1948 #endif /* CONFIG_CIFS_UPCALL */
1949 	case RawNTLMSSP:
1950 		sess_data->func = sess_auth_rawntlmssp_negotiate;
1951 		break;
1952 	default:
1953 		cifs_dbg(VFS, "secType %d not supported!\n", type);
1954 		return -ENOSYS;
1955 	}
1956 
1957 	return 0;
1958 }
1959 
1960 int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
1961 		   struct TCP_Server_Info *server,
1962 		   const struct nls_table *nls_cp)
1963 {
1964 	int rc = 0;
1965 	struct sess_data *sess_data;
1966 
1967 	if (ses == NULL) {
1968 		WARN(1, "%s: ses == NULL!", __func__);
1969 		return -EINVAL;
1970 	}
1971 
1972 	sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
1973 	if (!sess_data)
1974 		return -ENOMEM;
1975 
1976 	sess_data->xid = xid;
1977 	sess_data->ses = ses;
1978 	sess_data->server = server;
1979 	sess_data->buf0_type = CIFS_NO_BUFFER;
1980 	sess_data->nls_cp = (struct nls_table *) nls_cp;
1981 
1982 	rc = select_sec(sess_data);
1983 	if (rc)
1984 		goto out;
1985 
1986 	while (sess_data->func)
1987 		sess_data->func(sess_data);
1988 
1989 	/* Store result before we free sess_data */
1990 	rc = sess_data->result;
1991 
1992 out:
1993 	kfree_sensitive(sess_data);
1994 	return rc;
1995 }
1996 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
1997