xref: /linux/fs/smb/client/sess.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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 /*
351  * update the iface for the channel if necessary.
352  * Must be called with chan_lock held.
353  */
354 void
355 cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
356 {
357 	unsigned int chan_index;
358 	size_t iface_weight = 0, iface_min_speed = 0;
359 	struct cifs_server_iface *iface = NULL;
360 	struct cifs_server_iface *old_iface = NULL;
361 	struct cifs_server_iface *last_iface = NULL;
362 	struct sockaddr_storage ss;
363 
364 	spin_lock(&ses->chan_lock);
365 	chan_index = cifs_ses_get_chan_index(ses, server);
366 	if (chan_index == CIFS_INVAL_CHAN_INDEX) {
367 		spin_unlock(&ses->chan_lock);
368 		return;
369 	}
370 
371 	if (ses->chans[chan_index].iface) {
372 		old_iface = ses->chans[chan_index].iface;
373 		if (old_iface->is_active) {
374 			spin_unlock(&ses->chan_lock);
375 			return;
376 		}
377 	}
378 	spin_unlock(&ses->chan_lock);
379 
380 	spin_lock(&server->srv_lock);
381 	ss = server->dstaddr;
382 	spin_unlock(&server->srv_lock);
383 
384 	spin_lock(&ses->iface_lock);
385 	if (!ses->iface_count) {
386 		spin_unlock(&ses->iface_lock);
387 		cifs_dbg(ONCE, "server %s does not advertise interfaces\n", ses->server->hostname);
388 		return;
389 	}
390 
391 	last_iface = list_last_entry(&ses->iface_list, struct cifs_server_iface,
392 				     iface_head);
393 	iface_min_speed = last_iface->speed;
394 
395 	/* then look for a new one */
396 	list_for_each_entry(iface, &ses->iface_list, iface_head) {
397 		if (!chan_index) {
398 			/* if we're trying to get the updated iface for primary channel */
399 			if (!cifs_match_ipaddr((struct sockaddr *) &ss,
400 					       (struct sockaddr *) &iface->sockaddr))
401 				continue;
402 
403 			kref_get(&iface->refcount);
404 			break;
405 		}
406 
407 		/* do not mix rdma and non-rdma interfaces */
408 		if (iface->rdma_capable != server->rdma)
409 			continue;
410 
411 		if (!iface->is_active ||
412 		    (is_ses_using_iface(ses, iface) &&
413 		     !iface->rss_capable)) {
414 			continue;
415 		}
416 
417 		/* check if we already allocated enough channels */
418 		iface_weight = iface->speed / iface_min_speed;
419 
420 		if (iface->weight_fulfilled >= iface_weight)
421 			continue;
422 
423 		kref_get(&iface->refcount);
424 		break;
425 	}
426 
427 	if (list_entry_is_head(iface, &ses->iface_list, iface_head)) {
428 		iface = NULL;
429 		cifs_dbg(FYI, "unable to find a suitable iface\n");
430 	}
431 
432 	if (!iface) {
433 		if (!chan_index)
434 			cifs_dbg(FYI, "unable to get the interface matching: %pIS\n",
435 				 &ss);
436 		else {
437 			cifs_dbg(FYI, "unable to find another interface to replace: %pIS\n",
438 				 &old_iface->sockaddr);
439 		}
440 
441 		spin_unlock(&ses->iface_lock);
442 		return;
443 	}
444 
445 	/* now drop the ref to the current iface */
446 	if (old_iface) {
447 		cifs_dbg(FYI, "replacing iface: %pIS with %pIS\n",
448 			 &old_iface->sockaddr,
449 			 &iface->sockaddr);
450 
451 		old_iface->num_channels--;
452 		if (old_iface->weight_fulfilled)
453 			old_iface->weight_fulfilled--;
454 		iface->num_channels++;
455 		iface->weight_fulfilled++;
456 
457 		kref_put(&old_iface->refcount, release_iface);
458 	} else if (!chan_index) {
459 		/* special case: update interface for primary channel */
460 		cifs_dbg(FYI, "referencing primary channel iface: %pIS\n",
461 			 &iface->sockaddr);
462 		iface->num_channels++;
463 		iface->weight_fulfilled++;
464 	}
465 	spin_unlock(&ses->iface_lock);
466 
467 	spin_lock(&ses->chan_lock);
468 	chan_index = cifs_ses_get_chan_index(ses, server);
469 	if (chan_index == CIFS_INVAL_CHAN_INDEX) {
470 		spin_unlock(&ses->chan_lock);
471 		return;
472 	}
473 
474 	ses->chans[chan_index].iface = iface;
475 	spin_unlock(&ses->chan_lock);
476 }
477 
478 static int
479 cifs_ses_add_channel(struct cifs_ses *ses,
480 		     struct cifs_server_iface *iface)
481 {
482 	struct TCP_Server_Info *chan_server;
483 	struct cifs_chan *chan;
484 	struct smb3_fs_context *ctx;
485 	static const char unc_fmt[] = "\\%s\\foo";
486 	struct sockaddr_in *ipv4 = (struct sockaddr_in *)&iface->sockaddr;
487 	struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&iface->sockaddr;
488 	size_t len;
489 	int rc;
490 	unsigned int xid = get_xid();
491 
492 	if (iface->sockaddr.ss_family == AF_INET)
493 		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI4)\n",
494 			 ses, iface->speed, iface->rdma_capable ? "yes" : "no",
495 			 &ipv4->sin_addr);
496 	else
497 		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI6)\n",
498 			 ses, iface->speed, iface->rdma_capable ? "yes" : "no",
499 			 &ipv6->sin6_addr);
500 
501 	/*
502 	 * Setup a ctx with mostly the same info as the existing
503 	 * session and overwrite it with the requested iface data.
504 	 *
505 	 * We need to setup at least the fields used for negprot and
506 	 * sesssetup.
507 	 *
508 	 * We only need the ctx here, so we can reuse memory from
509 	 * the session and server without caring about memory
510 	 * management.
511 	 */
512 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
513 	if (!ctx) {
514 		rc = -ENOMEM;
515 		goto out_free_xid;
516 	}
517 
518 	/* Always make new connection for now (TODO?) */
519 	ctx->nosharesock = true;
520 
521 	/* Auth */
522 	ctx->domainauto = ses->domainAuto;
523 	ctx->domainname = ses->domainName;
524 
525 	/* no hostname for extra channels */
526 	ctx->server_hostname = "";
527 
528 	ctx->username = ses->user_name;
529 	ctx->password = ses->password;
530 	ctx->sectype = ses->sectype;
531 	ctx->sign = ses->sign;
532 
533 	/* UNC and paths */
534 	/* XXX: Use ses->server->hostname? */
535 	len = sizeof(unc_fmt) + SERVER_NAME_LEN_WITH_NULL;
536 	ctx->UNC = kzalloc(len, GFP_KERNEL);
537 	if (!ctx->UNC) {
538 		rc = -ENOMEM;
539 		goto out_free_ctx;
540 	}
541 	scnprintf(ctx->UNC, len, unc_fmt, ses->ip_addr);
542 	ctx->prepath = "";
543 
544 	/* Reuse same version as master connection */
545 	ctx->vals = ses->server->vals;
546 	ctx->ops = ses->server->ops;
547 
548 	ctx->noblocksnd = ses->server->noblocksnd;
549 	ctx->noautotune = ses->server->noautotune;
550 	ctx->sockopt_tcp_nodelay = ses->server->tcp_nodelay;
551 	ctx->echo_interval = ses->server->echo_interval / HZ;
552 	ctx->max_credits = ses->server->max_credits;
553 
554 	/*
555 	 * This will be used for encoding/decoding user/domain/pw
556 	 * during sess setup auth.
557 	 */
558 	ctx->local_nls = ses->local_nls;
559 
560 	/* Use RDMA if possible */
561 	ctx->rdma = iface->rdma_capable;
562 	memcpy(&ctx->dstaddr, &iface->sockaddr, sizeof(ctx->dstaddr));
563 
564 	/* reuse master con client guid */
565 	memcpy(&ctx->client_guid, ses->server->client_guid,
566 	       sizeof(ctx->client_guid));
567 	ctx->use_client_guid = true;
568 
569 	chan_server = cifs_get_tcp_session(ctx, ses->server);
570 
571 	spin_lock(&ses->chan_lock);
572 	chan = &ses->chans[ses->chan_count];
573 	chan->server = chan_server;
574 	if (IS_ERR(chan->server)) {
575 		rc = PTR_ERR(chan->server);
576 		chan->server = NULL;
577 		spin_unlock(&ses->chan_lock);
578 		goto out;
579 	}
580 	chan->iface = iface;
581 	ses->chan_count++;
582 	atomic_set(&ses->chan_seq, 0);
583 
584 	/* Mark this channel as needing connect/setup */
585 	cifs_chan_set_need_reconnect(ses, chan->server);
586 
587 	spin_unlock(&ses->chan_lock);
588 
589 	mutex_lock(&ses->session_mutex);
590 	/*
591 	 * We need to allocate the server crypto now as we will need
592 	 * to sign packets before we generate the channel signing key
593 	 * (we sign with the session key)
594 	 */
595 	rc = smb311_crypto_shash_allocate(chan->server);
596 	if (rc) {
597 		cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
598 		mutex_unlock(&ses->session_mutex);
599 		goto out;
600 	}
601 
602 	rc = cifs_negotiate_protocol(xid, ses, chan->server);
603 	if (!rc)
604 		rc = cifs_setup_session(xid, ses, chan->server, ses->local_nls);
605 
606 	mutex_unlock(&ses->session_mutex);
607 
608 out:
609 	if (rc && chan->server) {
610 		cifs_put_tcp_session(chan->server, 0);
611 
612 		spin_lock(&ses->chan_lock);
613 
614 		/* we rely on all bits beyond chan_count to be clear */
615 		cifs_chan_clear_need_reconnect(ses, chan->server);
616 		ses->chan_count--;
617 		/*
618 		 * chan_count should never reach 0 as at least the primary
619 		 * channel is always allocated
620 		 */
621 		WARN_ON(ses->chan_count < 1);
622 		spin_unlock(&ses->chan_lock);
623 	}
624 
625 	kfree(ctx->UNC);
626 out_free_ctx:
627 	kfree(ctx);
628 out_free_xid:
629 	free_xid(xid);
630 	return rc;
631 }
632 
633 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
634 static __u32 cifs_ssetup_hdr(struct cifs_ses *ses,
635 			     struct TCP_Server_Info *server,
636 			     SESSION_SETUP_ANDX *pSMB)
637 {
638 	__u32 capabilities = 0;
639 
640 	/* init fields common to all four types of SessSetup */
641 	/* Note that offsets for first seven fields in req struct are same  */
642 	/*	in CIFS Specs so does not matter which of 3 forms of struct */
643 	/*	that we use in next few lines                               */
644 	/* Note that header is initialized to zero in header_assemble */
645 	pSMB->req.AndXCommand = 0xFF;
646 	pSMB->req.MaxBufferSize = cpu_to_le16(min_t(u32,
647 					CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4,
648 					USHRT_MAX));
649 	pSMB->req.MaxMpxCount = cpu_to_le16(server->maxReq);
650 	pSMB->req.VcNumber = cpu_to_le16(1);
651 
652 	/* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
653 
654 	/* BB verify whether signing required on neg or just auth frame (and NTLM case) */
655 
656 	capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
657 			CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
658 
659 	if (server->sign)
660 		pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
661 
662 	if (ses->capabilities & CAP_UNICODE) {
663 		pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
664 		capabilities |= CAP_UNICODE;
665 	}
666 	if (ses->capabilities & CAP_STATUS32) {
667 		pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
668 		capabilities |= CAP_STATUS32;
669 	}
670 	if (ses->capabilities & CAP_DFS) {
671 		pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
672 		capabilities |= CAP_DFS;
673 	}
674 	if (ses->capabilities & CAP_UNIX)
675 		capabilities |= CAP_UNIX;
676 
677 	return capabilities;
678 }
679 
680 static void
681 unicode_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
682 {
683 	char *bcc_ptr = *pbcc_area;
684 	int bytes_ret = 0;
685 
686 	/* Copy OS version */
687 	bytes_ret = cifs_strtoUTF16((__le16 *)bcc_ptr, "Linux version ", 32,
688 				    nls_cp);
689 	bcc_ptr += 2 * bytes_ret;
690 	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, init_utsname()->release,
691 				    32, nls_cp);
692 	bcc_ptr += 2 * bytes_ret;
693 	bcc_ptr += 2; /* trailing null */
694 
695 	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
696 				    32, nls_cp);
697 	bcc_ptr += 2 * bytes_ret;
698 	bcc_ptr += 2; /* trailing null */
699 
700 	*pbcc_area = bcc_ptr;
701 }
702 
703 static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
704 				   const struct nls_table *nls_cp)
705 {
706 	char *bcc_ptr = *pbcc_area;
707 	int bytes_ret = 0;
708 
709 	/* copy domain */
710 	if (ses->domainName == NULL) {
711 		/*
712 		 * Sending null domain better than using a bogus domain name (as
713 		 * we did briefly in 2.6.18) since server will use its default
714 		 */
715 		*bcc_ptr = 0;
716 		*(bcc_ptr+1) = 0;
717 		bytes_ret = 0;
718 	} else
719 		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
720 					    CIFS_MAX_DOMAINNAME_LEN, nls_cp);
721 	bcc_ptr += 2 * bytes_ret;
722 	bcc_ptr += 2;  /* account for null terminator */
723 
724 	*pbcc_area = bcc_ptr;
725 }
726 
727 static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
728 				   const struct nls_table *nls_cp)
729 {
730 	char *bcc_ptr = *pbcc_area;
731 	int bytes_ret = 0;
732 
733 	/* BB FIXME add check that strings less than 335 or will need to send as arrays */
734 
735 	/* copy user */
736 	if (ses->user_name == NULL) {
737 		/* null user mount */
738 		*bcc_ptr = 0;
739 		*(bcc_ptr+1) = 0;
740 	} else {
741 		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->user_name,
742 					    CIFS_MAX_USERNAME_LEN, nls_cp);
743 	}
744 	bcc_ptr += 2 * bytes_ret;
745 	bcc_ptr += 2; /* account for null termination */
746 
747 	unicode_domain_string(&bcc_ptr, ses, nls_cp);
748 	unicode_oslm_strings(&bcc_ptr, nls_cp);
749 
750 	*pbcc_area = bcc_ptr;
751 }
752 
753 static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
754 				 const struct nls_table *nls_cp)
755 {
756 	char *bcc_ptr = *pbcc_area;
757 	int len;
758 
759 	/* copy user */
760 	/* BB what about null user mounts - check that we do this BB */
761 	/* copy user */
762 	if (ses->user_name != NULL) {
763 		len = strscpy(bcc_ptr, ses->user_name, CIFS_MAX_USERNAME_LEN);
764 		if (WARN_ON_ONCE(len < 0))
765 			len = CIFS_MAX_USERNAME_LEN - 1;
766 		bcc_ptr += len;
767 	}
768 	/* else null user mount */
769 	*bcc_ptr = 0;
770 	bcc_ptr++; /* account for null termination */
771 
772 	/* copy domain */
773 	if (ses->domainName != NULL) {
774 		len = strscpy(bcc_ptr, ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
775 		if (WARN_ON_ONCE(len < 0))
776 			len = CIFS_MAX_DOMAINNAME_LEN - 1;
777 		bcc_ptr += len;
778 	} /* else we send a null domain name so server will default to its own domain */
779 	*bcc_ptr = 0;
780 	bcc_ptr++;
781 
782 	/* BB check for overflow here */
783 
784 	strcpy(bcc_ptr, "Linux version ");
785 	bcc_ptr += strlen("Linux version ");
786 	strcpy(bcc_ptr, init_utsname()->release);
787 	bcc_ptr += strlen(init_utsname()->release) + 1;
788 
789 	strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
790 	bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;
791 
792 	*pbcc_area = bcc_ptr;
793 }
794 
795 static void
796 decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifs_ses *ses,
797 		      const struct nls_table *nls_cp)
798 {
799 	int len;
800 	char *data = *pbcc_area;
801 
802 	cifs_dbg(FYI, "bleft %d\n", bleft);
803 
804 	kfree(ses->serverOS);
805 	ses->serverOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
806 	cifs_dbg(FYI, "serverOS=%s\n", ses->serverOS);
807 	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
808 	data += len;
809 	bleft -= len;
810 	if (bleft <= 0)
811 		return;
812 
813 	kfree(ses->serverNOS);
814 	ses->serverNOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
815 	cifs_dbg(FYI, "serverNOS=%s\n", ses->serverNOS);
816 	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
817 	data += len;
818 	bleft -= len;
819 	if (bleft <= 0)
820 		return;
821 
822 	kfree(ses->serverDomain);
823 	ses->serverDomain = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
824 	cifs_dbg(FYI, "serverDomain=%s\n", ses->serverDomain);
825 
826 	return;
827 }
828 
829 static void decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
830 				struct cifs_ses *ses,
831 				const struct nls_table *nls_cp)
832 {
833 	int len;
834 	char *bcc_ptr = *pbcc_area;
835 
836 	cifs_dbg(FYI, "decode sessetup ascii. bleft %d\n", bleft);
837 
838 	len = strnlen(bcc_ptr, bleft);
839 	if (len >= bleft)
840 		return;
841 
842 	kfree(ses->serverOS);
843 
844 	ses->serverOS = kmalloc(len + 1, GFP_KERNEL);
845 	if (ses->serverOS) {
846 		memcpy(ses->serverOS, bcc_ptr, len);
847 		ses->serverOS[len] = 0;
848 		if (strncmp(ses->serverOS, "OS/2", 4) == 0)
849 			cifs_dbg(FYI, "OS/2 server\n");
850 	}
851 
852 	bcc_ptr += len + 1;
853 	bleft -= len + 1;
854 
855 	len = strnlen(bcc_ptr, bleft);
856 	if (len >= bleft)
857 		return;
858 
859 	kfree(ses->serverNOS);
860 
861 	ses->serverNOS = kmalloc(len + 1, GFP_KERNEL);
862 	if (ses->serverNOS) {
863 		memcpy(ses->serverNOS, bcc_ptr, len);
864 		ses->serverNOS[len] = 0;
865 	}
866 
867 	bcc_ptr += len + 1;
868 	bleft -= len + 1;
869 
870 	len = strnlen(bcc_ptr, bleft);
871 	if (len > bleft)
872 		return;
873 
874 	/*
875 	 * No domain field in LANMAN case. Domain is
876 	 * returned by old servers in the SMB negprot response
877 	 *
878 	 * BB For newer servers which do not support Unicode,
879 	 * but thus do return domain here, we could add parsing
880 	 * for it later, but it is not very important
881 	 */
882 	cifs_dbg(FYI, "ascii: bytes left %d\n", bleft);
883 }
884 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
885 
886 int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
887 				    struct cifs_ses *ses)
888 {
889 	unsigned int tioffset; /* challenge message target info area */
890 	unsigned int tilen; /* challenge message target info area length  */
891 	CHALLENGE_MESSAGE *pblob = (CHALLENGE_MESSAGE *)bcc_ptr;
892 	__u32 server_flags;
893 
894 	if (blob_len < sizeof(CHALLENGE_MESSAGE)) {
895 		cifs_dbg(VFS, "challenge blob len %d too small\n", blob_len);
896 		return -EINVAL;
897 	}
898 
899 	if (memcmp(pblob->Signature, "NTLMSSP", 8)) {
900 		cifs_dbg(VFS, "blob signature incorrect %s\n",
901 			 pblob->Signature);
902 		return -EINVAL;
903 	}
904 	if (pblob->MessageType != NtLmChallenge) {
905 		cifs_dbg(VFS, "Incorrect message type %d\n",
906 			 pblob->MessageType);
907 		return -EINVAL;
908 	}
909 
910 	server_flags = le32_to_cpu(pblob->NegotiateFlags);
911 	cifs_dbg(FYI, "%s: negotiate=0x%08x challenge=0x%08x\n", __func__,
912 		 ses->ntlmssp->client_flags, server_flags);
913 
914 	if ((ses->ntlmssp->client_flags & (NTLMSSP_NEGOTIATE_SEAL | NTLMSSP_NEGOTIATE_SIGN)) &&
915 	    (!(server_flags & NTLMSSP_NEGOTIATE_56) && !(server_flags & NTLMSSP_NEGOTIATE_128))) {
916 		cifs_dbg(VFS, "%s: requested signing/encryption but server did not return either 56-bit or 128-bit session key size\n",
917 			 __func__);
918 		return -EINVAL;
919 	}
920 	if (!(server_flags & NTLMSSP_NEGOTIATE_NTLM) && !(server_flags & NTLMSSP_NEGOTIATE_EXTENDED_SEC)) {
921 		cifs_dbg(VFS, "%s: server does not seem to support either NTLMv1 or NTLMv2\n", __func__);
922 		return -EINVAL;
923 	}
924 	if (ses->server->sign && !(server_flags & NTLMSSP_NEGOTIATE_SIGN)) {
925 		cifs_dbg(VFS, "%s: forced packet signing but server does not seem to support it\n",
926 			 __func__);
927 		return -EOPNOTSUPP;
928 	}
929 	if ((ses->ntlmssp->client_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
930 	    !(server_flags & NTLMSSP_NEGOTIATE_KEY_XCH))
931 		pr_warn_once("%s: authentication has been weakened as server does not support key exchange\n",
932 			     __func__);
933 
934 	ses->ntlmssp->server_flags = server_flags;
935 
936 	memcpy(ses->ntlmssp->cryptkey, pblob->Challenge, CIFS_CRYPTO_KEY_SIZE);
937 	/*
938 	 * In particular we can examine sign flags
939 	 *
940 	 * BB spec says that if AvId field of MsvAvTimestamp is populated then
941 	 * we must set the MIC field of the AUTHENTICATE_MESSAGE
942 	 */
943 
944 	tioffset = le32_to_cpu(pblob->TargetInfoArray.BufferOffset);
945 	tilen = le16_to_cpu(pblob->TargetInfoArray.Length);
946 	if (tioffset > blob_len || tioffset + tilen > blob_len) {
947 		cifs_dbg(VFS, "tioffset + tilen too high %u + %u\n",
948 			 tioffset, tilen);
949 		return -EINVAL;
950 	}
951 	if (tilen) {
952 		kfree_sensitive(ses->auth_key.response);
953 		ses->auth_key.response = kmemdup(bcc_ptr + tioffset, tilen,
954 						 GFP_KERNEL);
955 		if (!ses->auth_key.response) {
956 			cifs_dbg(VFS, "Challenge target info alloc failure\n");
957 			return -ENOMEM;
958 		}
959 		ses->auth_key.len = tilen;
960 	}
961 
962 	return 0;
963 }
964 
965 static int size_of_ntlmssp_blob(struct cifs_ses *ses, int base_size)
966 {
967 	int sz = base_size + ses->auth_key.len
968 		- CIFS_SESS_KEY_SIZE + CIFS_CPHTXT_SIZE + 2;
969 
970 	if (ses->domainName)
971 		sz += sizeof(__le16) * strnlen(ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
972 	else
973 		sz += sizeof(__le16);
974 
975 	if (ses->user_name)
976 		sz += sizeof(__le16) * strnlen(ses->user_name, CIFS_MAX_USERNAME_LEN);
977 	else
978 		sz += sizeof(__le16);
979 
980 	if (ses->workstation_name[0])
981 		sz += sizeof(__le16) * strnlen(ses->workstation_name,
982 					       ntlmssp_workstation_name_size(ses));
983 	else
984 		sz += sizeof(__le16);
985 
986 	return sz;
987 }
988 
989 static inline void cifs_security_buffer_from_str(SECURITY_BUFFER *pbuf,
990 						 char *str_value,
991 						 int str_length,
992 						 unsigned char *pstart,
993 						 unsigned char **pcur,
994 						 const struct nls_table *nls_cp)
995 {
996 	unsigned char *tmp = pstart;
997 	int len;
998 
999 	if (!pbuf)
1000 		return;
1001 
1002 	if (!pcur)
1003 		pcur = &tmp;
1004 
1005 	if (!str_value) {
1006 		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
1007 		pbuf->Length = 0;
1008 		pbuf->MaximumLength = 0;
1009 		*pcur += sizeof(__le16);
1010 	} else {
1011 		len = cifs_strtoUTF16((__le16 *)*pcur,
1012 				      str_value,
1013 				      str_length,
1014 				      nls_cp);
1015 		len *= sizeof(__le16);
1016 		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
1017 		pbuf->Length = cpu_to_le16(len);
1018 		pbuf->MaximumLength = cpu_to_le16(len);
1019 		*pcur += len;
1020 	}
1021 }
1022 
1023 /* BB Move to ntlmssp.c eventually */
1024 
1025 int build_ntlmssp_negotiate_blob(unsigned char **pbuffer,
1026 				 u16 *buflen,
1027 				 struct cifs_ses *ses,
1028 				 struct TCP_Server_Info *server,
1029 				 const struct nls_table *nls_cp)
1030 {
1031 	int rc = 0;
1032 	NEGOTIATE_MESSAGE *sec_blob;
1033 	__u32 flags;
1034 	unsigned char *tmp;
1035 	int len;
1036 
1037 	len = size_of_ntlmssp_blob(ses, sizeof(NEGOTIATE_MESSAGE));
1038 	*pbuffer = kmalloc(len, GFP_KERNEL);
1039 	if (!*pbuffer) {
1040 		rc = -ENOMEM;
1041 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1042 		*buflen = 0;
1043 		goto setup_ntlm_neg_ret;
1044 	}
1045 	sec_blob = (NEGOTIATE_MESSAGE *)*pbuffer;
1046 
1047 	memset(*pbuffer, 0, sizeof(NEGOTIATE_MESSAGE));
1048 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1049 	sec_blob->MessageType = NtLmNegotiate;
1050 
1051 	/* BB is NTLMV2 session security format easier to use here? */
1052 	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
1053 		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
1054 		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
1055 		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
1056 		NTLMSSP_NEGOTIATE_SIGN;
1057 	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
1058 		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
1059 
1060 	tmp = *pbuffer + sizeof(NEGOTIATE_MESSAGE);
1061 	ses->ntlmssp->client_flags = flags;
1062 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1063 
1064 	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
1065 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1066 				      NULL,
1067 				      CIFS_MAX_DOMAINNAME_LEN,
1068 				      *pbuffer, &tmp,
1069 				      nls_cp);
1070 
1071 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1072 				      NULL,
1073 				      CIFS_MAX_WORKSTATION_LEN,
1074 				      *pbuffer, &tmp,
1075 				      nls_cp);
1076 
1077 	*buflen = tmp - *pbuffer;
1078 setup_ntlm_neg_ret:
1079 	return rc;
1080 }
1081 
1082 /*
1083  * Build ntlmssp blob with additional fields, such as version,
1084  * supported by modern servers. For safety limit to SMB3 or later
1085  * See notes in MS-NLMP Section 2.2.2.1 e.g.
1086  */
1087 int build_ntlmssp_smb3_negotiate_blob(unsigned char **pbuffer,
1088 				 u16 *buflen,
1089 				 struct cifs_ses *ses,
1090 				 struct TCP_Server_Info *server,
1091 				 const struct nls_table *nls_cp)
1092 {
1093 	int rc = 0;
1094 	struct negotiate_message *sec_blob;
1095 	__u32 flags;
1096 	unsigned char *tmp;
1097 	int len;
1098 
1099 	len = size_of_ntlmssp_blob(ses, sizeof(struct negotiate_message));
1100 	*pbuffer = kmalloc(len, GFP_KERNEL);
1101 	if (!*pbuffer) {
1102 		rc = -ENOMEM;
1103 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1104 		*buflen = 0;
1105 		goto setup_ntlm_smb3_neg_ret;
1106 	}
1107 	sec_blob = (struct negotiate_message *)*pbuffer;
1108 
1109 	memset(*pbuffer, 0, sizeof(struct negotiate_message));
1110 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1111 	sec_blob->MessageType = NtLmNegotiate;
1112 
1113 	/* BB is NTLMV2 session security format easier to use here? */
1114 	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
1115 		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
1116 		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
1117 		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
1118 		NTLMSSP_NEGOTIATE_SIGN | NTLMSSP_NEGOTIATE_VERSION;
1119 	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
1120 		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
1121 
1122 	sec_blob->Version.ProductMajorVersion = LINUX_VERSION_MAJOR;
1123 	sec_blob->Version.ProductMinorVersion = LINUX_VERSION_PATCHLEVEL;
1124 	sec_blob->Version.ProductBuild = cpu_to_le16(SMB3_PRODUCT_BUILD);
1125 	sec_blob->Version.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
1126 
1127 	tmp = *pbuffer + sizeof(struct negotiate_message);
1128 	ses->ntlmssp->client_flags = flags;
1129 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1130 
1131 	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
1132 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1133 				      NULL,
1134 				      CIFS_MAX_DOMAINNAME_LEN,
1135 				      *pbuffer, &tmp,
1136 				      nls_cp);
1137 
1138 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1139 				      NULL,
1140 				      CIFS_MAX_WORKSTATION_LEN,
1141 				      *pbuffer, &tmp,
1142 				      nls_cp);
1143 
1144 	*buflen = tmp - *pbuffer;
1145 setup_ntlm_smb3_neg_ret:
1146 	return rc;
1147 }
1148 
1149 
1150 /* See MS-NLMP 2.2.1.3 */
1151 int build_ntlmssp_auth_blob(unsigned char **pbuffer,
1152 					u16 *buflen,
1153 				   struct cifs_ses *ses,
1154 				   struct TCP_Server_Info *server,
1155 				   const struct nls_table *nls_cp)
1156 {
1157 	int rc;
1158 	AUTHENTICATE_MESSAGE *sec_blob;
1159 	__u32 flags;
1160 	unsigned char *tmp;
1161 	int len;
1162 
1163 	rc = setup_ntlmv2_rsp(ses, nls_cp);
1164 	if (rc) {
1165 		cifs_dbg(VFS, "Error %d during NTLMSSP authentication\n", rc);
1166 		*buflen = 0;
1167 		goto setup_ntlmv2_ret;
1168 	}
1169 
1170 	len = size_of_ntlmssp_blob(ses, sizeof(AUTHENTICATE_MESSAGE));
1171 	*pbuffer = kmalloc(len, GFP_KERNEL);
1172 	if (!*pbuffer) {
1173 		rc = -ENOMEM;
1174 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1175 		*buflen = 0;
1176 		goto setup_ntlmv2_ret;
1177 	}
1178 	sec_blob = (AUTHENTICATE_MESSAGE *)*pbuffer;
1179 
1180 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1181 	sec_blob->MessageType = NtLmAuthenticate;
1182 
1183 	/* send version information in ntlmssp authenticate also */
1184 	flags = ses->ntlmssp->server_flags | NTLMSSP_REQUEST_TARGET |
1185 		NTLMSSP_NEGOTIATE_TARGET_INFO | NTLMSSP_NEGOTIATE_VERSION |
1186 		NTLMSSP_NEGOTIATE_WORKSTATION_SUPPLIED;
1187 
1188 	sec_blob->Version.ProductMajorVersion = LINUX_VERSION_MAJOR;
1189 	sec_blob->Version.ProductMinorVersion = LINUX_VERSION_PATCHLEVEL;
1190 	sec_blob->Version.ProductBuild = cpu_to_le16(SMB3_PRODUCT_BUILD);
1191 	sec_blob->Version.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
1192 
1193 	tmp = *pbuffer + sizeof(AUTHENTICATE_MESSAGE);
1194 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1195 
1196 	sec_blob->LmChallengeResponse.BufferOffset =
1197 				cpu_to_le32(sizeof(AUTHENTICATE_MESSAGE));
1198 	sec_blob->LmChallengeResponse.Length = 0;
1199 	sec_blob->LmChallengeResponse.MaximumLength = 0;
1200 
1201 	sec_blob->NtChallengeResponse.BufferOffset =
1202 				cpu_to_le32(tmp - *pbuffer);
1203 	if (ses->user_name != NULL) {
1204 		memcpy(tmp, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
1205 				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1206 		tmp += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
1207 
1208 		sec_blob->NtChallengeResponse.Length =
1209 				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1210 		sec_blob->NtChallengeResponse.MaximumLength =
1211 				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1212 	} else {
1213 		/*
1214 		 * don't send an NT Response for anonymous access
1215 		 */
1216 		sec_blob->NtChallengeResponse.Length = 0;
1217 		sec_blob->NtChallengeResponse.MaximumLength = 0;
1218 	}
1219 
1220 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1221 				      ses->domainName,
1222 				      CIFS_MAX_DOMAINNAME_LEN,
1223 				      *pbuffer, &tmp,
1224 				      nls_cp);
1225 
1226 	cifs_security_buffer_from_str(&sec_blob->UserName,
1227 				      ses->user_name,
1228 				      CIFS_MAX_USERNAME_LEN,
1229 				      *pbuffer, &tmp,
1230 				      nls_cp);
1231 
1232 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1233 				      ses->workstation_name,
1234 				      ntlmssp_workstation_name_size(ses),
1235 				      *pbuffer, &tmp,
1236 				      nls_cp);
1237 
1238 	if ((ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
1239 	    (!ses->server->session_estab || ses->ntlmssp->sesskey_per_smbsess) &&
1240 	    !calc_seckey(ses)) {
1241 		memcpy(tmp, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
1242 		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
1243 		sec_blob->SessionKey.Length = cpu_to_le16(CIFS_CPHTXT_SIZE);
1244 		sec_blob->SessionKey.MaximumLength =
1245 				cpu_to_le16(CIFS_CPHTXT_SIZE);
1246 		tmp += CIFS_CPHTXT_SIZE;
1247 	} else {
1248 		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
1249 		sec_blob->SessionKey.Length = 0;
1250 		sec_blob->SessionKey.MaximumLength = 0;
1251 	}
1252 
1253 	*buflen = tmp - *pbuffer;
1254 setup_ntlmv2_ret:
1255 	return rc;
1256 }
1257 
1258 enum securityEnum
1259 cifs_select_sectype(struct TCP_Server_Info *server, enum securityEnum requested)
1260 {
1261 	switch (server->negflavor) {
1262 	case CIFS_NEGFLAVOR_EXTENDED:
1263 		switch (requested) {
1264 		case Kerberos:
1265 		case RawNTLMSSP:
1266 			return requested;
1267 		case Unspecified:
1268 			if (server->sec_ntlmssp &&
1269 			    (global_secflags & CIFSSEC_MAY_NTLMSSP))
1270 				return RawNTLMSSP;
1271 			if ((server->sec_kerberos || server->sec_mskerberos) &&
1272 			    (global_secflags & CIFSSEC_MAY_KRB5))
1273 				return Kerberos;
1274 			fallthrough;
1275 		default:
1276 			return Unspecified;
1277 		}
1278 	case CIFS_NEGFLAVOR_UNENCAP:
1279 		switch (requested) {
1280 		case NTLMv2:
1281 			return requested;
1282 		case Unspecified:
1283 			if (global_secflags & CIFSSEC_MAY_NTLMV2)
1284 				return NTLMv2;
1285 			break;
1286 		default:
1287 			break;
1288 		}
1289 		fallthrough;
1290 	default:
1291 		return Unspecified;
1292 	}
1293 }
1294 
1295 struct sess_data {
1296 	unsigned int xid;
1297 	struct cifs_ses *ses;
1298 	struct TCP_Server_Info *server;
1299 	struct nls_table *nls_cp;
1300 	void (*func)(struct sess_data *);
1301 	int result;
1302 
1303 	/* we will send the SMB in three pieces:
1304 	 * a fixed length beginning part, an optional
1305 	 * SPNEGO blob (which can be zero length), and a
1306 	 * last part which will include the strings
1307 	 * and rest of bcc area. This allows us to avoid
1308 	 * a large buffer 17K allocation
1309 	 */
1310 	int buf0_type;
1311 	struct kvec iov[3];
1312 };
1313 
1314 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
1315 static int
1316 sess_alloc_buffer(struct sess_data *sess_data, int wct)
1317 {
1318 	int rc;
1319 	struct cifs_ses *ses = sess_data->ses;
1320 	struct smb_hdr *smb_buf;
1321 
1322 	rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
1323 				  (void **)&smb_buf);
1324 
1325 	if (rc)
1326 		return rc;
1327 
1328 	sess_data->iov[0].iov_base = (char *)smb_buf;
1329 	sess_data->iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;
1330 	/*
1331 	 * This variable will be used to clear the buffer
1332 	 * allocated above in case of any error in the calling function.
1333 	 */
1334 	sess_data->buf0_type = CIFS_SMALL_BUFFER;
1335 
1336 	/* 2000 big enough to fit max user, domain, NOS name etc. */
1337 	sess_data->iov[2].iov_base = kmalloc(2000, GFP_KERNEL);
1338 	if (!sess_data->iov[2].iov_base) {
1339 		rc = -ENOMEM;
1340 		goto out_free_smb_buf;
1341 	}
1342 
1343 	return 0;
1344 
1345 out_free_smb_buf:
1346 	cifs_small_buf_release(smb_buf);
1347 	sess_data->iov[0].iov_base = NULL;
1348 	sess_data->iov[0].iov_len = 0;
1349 	sess_data->buf0_type = CIFS_NO_BUFFER;
1350 	return rc;
1351 }
1352 
1353 static void
1354 sess_free_buffer(struct sess_data *sess_data)
1355 {
1356 	struct kvec *iov = sess_data->iov;
1357 
1358 	/*
1359 	 * Zero the session data before freeing, as it might contain sensitive info (keys, etc).
1360 	 * Note that iov[1] is already freed by caller.
1361 	 */
1362 	if (sess_data->buf0_type != CIFS_NO_BUFFER && iov[0].iov_base)
1363 		memzero_explicit(iov[0].iov_base, iov[0].iov_len);
1364 
1365 	free_rsp_buf(sess_data->buf0_type, iov[0].iov_base);
1366 	sess_data->buf0_type = CIFS_NO_BUFFER;
1367 	kfree_sensitive(iov[2].iov_base);
1368 }
1369 
1370 static int
1371 sess_establish_session(struct sess_data *sess_data)
1372 {
1373 	struct cifs_ses *ses = sess_data->ses;
1374 	struct TCP_Server_Info *server = sess_data->server;
1375 
1376 	cifs_server_lock(server);
1377 	if (!server->session_estab) {
1378 		if (server->sign) {
1379 			server->session_key.response =
1380 				kmemdup(ses->auth_key.response,
1381 				ses->auth_key.len, GFP_KERNEL);
1382 			if (!server->session_key.response) {
1383 				cifs_server_unlock(server);
1384 				return -ENOMEM;
1385 			}
1386 			server->session_key.len =
1387 						ses->auth_key.len;
1388 		}
1389 		server->sequence_number = 0x2;
1390 		server->session_estab = true;
1391 	}
1392 	cifs_server_unlock(server);
1393 
1394 	cifs_dbg(FYI, "CIFS session established successfully\n");
1395 	return 0;
1396 }
1397 
1398 static int
1399 sess_sendreceive(struct sess_data *sess_data)
1400 {
1401 	int rc;
1402 	struct smb_hdr *smb_buf = (struct smb_hdr *) sess_data->iov[0].iov_base;
1403 	__u16 count;
1404 	struct kvec rsp_iov = { NULL, 0 };
1405 
1406 	count = sess_data->iov[1].iov_len + sess_data->iov[2].iov_len;
1407 	be32_add_cpu(&smb_buf->smb_buf_length, count);
1408 	put_bcc(count, smb_buf);
1409 
1410 	rc = SendReceive2(sess_data->xid, sess_data->ses,
1411 			  sess_data->iov, 3 /* num_iovecs */,
1412 			  &sess_data->buf0_type,
1413 			  CIFS_LOG_ERROR, &rsp_iov);
1414 	cifs_small_buf_release(sess_data->iov[0].iov_base);
1415 	memcpy(&sess_data->iov[0], &rsp_iov, sizeof(struct kvec));
1416 
1417 	return rc;
1418 }
1419 
1420 static void
1421 sess_auth_ntlmv2(struct sess_data *sess_data)
1422 {
1423 	int rc = 0;
1424 	struct smb_hdr *smb_buf;
1425 	SESSION_SETUP_ANDX *pSMB;
1426 	char *bcc_ptr;
1427 	struct cifs_ses *ses = sess_data->ses;
1428 	struct TCP_Server_Info *server = sess_data->server;
1429 	__u32 capabilities;
1430 	__u16 bytes_remaining;
1431 
1432 	/* old style NTLM sessionsetup */
1433 	/* wct = 13 */
1434 	rc = sess_alloc_buffer(sess_data, 13);
1435 	if (rc)
1436 		goto out;
1437 
1438 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1439 	bcc_ptr = sess_data->iov[2].iov_base;
1440 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1441 
1442 	pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
1443 
1444 	/* LM2 password would be here if we supported it */
1445 	pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
1446 
1447 	if (ses->user_name != NULL) {
1448 		/* calculate nlmv2 response and session key */
1449 		rc = setup_ntlmv2_rsp(ses, sess_data->nls_cp);
1450 		if (rc) {
1451 			cifs_dbg(VFS, "Error %d during NTLMv2 authentication\n", rc);
1452 			goto out;
1453 		}
1454 
1455 		memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
1456 				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1457 		bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
1458 
1459 		/* set case sensitive password length after tilen may get
1460 		 * assigned, tilen is 0 otherwise.
1461 		 */
1462 		pSMB->req_no_secext.CaseSensitivePasswordLength =
1463 			cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1464 	} else {
1465 		pSMB->req_no_secext.CaseSensitivePasswordLength = 0;
1466 	}
1467 
1468 	if (ses->capabilities & CAP_UNICODE) {
1469 		if (!IS_ALIGNED(sess_data->iov[0].iov_len, 2)) {
1470 			*bcc_ptr = 0;
1471 			bcc_ptr++;
1472 		}
1473 		unicode_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1474 	} else {
1475 		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1476 	}
1477 
1478 
1479 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1480 			(long) sess_data->iov[2].iov_base;
1481 
1482 	rc = sess_sendreceive(sess_data);
1483 	if (rc)
1484 		goto out;
1485 
1486 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1487 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1488 
1489 	if (smb_buf->WordCount != 3) {
1490 		rc = -EIO;
1491 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1492 		goto out;
1493 	}
1494 
1495 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1496 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1497 
1498 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1499 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1500 
1501 	bytes_remaining = get_bcc(smb_buf);
1502 	bcc_ptr = pByteArea(smb_buf);
1503 
1504 	/* BB check if Unicode and decode strings */
1505 	if (bytes_remaining == 0) {
1506 		/* no string area to decode, do nothing */
1507 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1508 		/* unicode string area must be word-aligned */
1509 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1510 			++bcc_ptr;
1511 			--bytes_remaining;
1512 		}
1513 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1514 				      sess_data->nls_cp);
1515 	} else {
1516 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1517 				    sess_data->nls_cp);
1518 	}
1519 
1520 	rc = sess_establish_session(sess_data);
1521 out:
1522 	sess_data->result = rc;
1523 	sess_data->func = NULL;
1524 	sess_free_buffer(sess_data);
1525 	kfree_sensitive(ses->auth_key.response);
1526 	ses->auth_key.response = NULL;
1527 }
1528 
1529 #ifdef CONFIG_CIFS_UPCALL
1530 static void
1531 sess_auth_kerberos(struct sess_data *sess_data)
1532 {
1533 	int rc = 0;
1534 	struct smb_hdr *smb_buf;
1535 	SESSION_SETUP_ANDX *pSMB;
1536 	char *bcc_ptr;
1537 	struct cifs_ses *ses = sess_data->ses;
1538 	struct TCP_Server_Info *server = sess_data->server;
1539 	__u32 capabilities;
1540 	__u16 bytes_remaining;
1541 	struct key *spnego_key = NULL;
1542 	struct cifs_spnego_msg *msg;
1543 	u16 blob_len;
1544 
1545 	/* extended security */
1546 	/* wct = 12 */
1547 	rc = sess_alloc_buffer(sess_data, 12);
1548 	if (rc)
1549 		goto out;
1550 
1551 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1552 	bcc_ptr = sess_data->iov[2].iov_base;
1553 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1554 
1555 	spnego_key = cifs_get_spnego_key(ses, server);
1556 	if (IS_ERR(spnego_key)) {
1557 		rc = PTR_ERR(spnego_key);
1558 		spnego_key = NULL;
1559 		goto out;
1560 	}
1561 
1562 	msg = spnego_key->payload.data[0];
1563 	/*
1564 	 * check version field to make sure that cifs.upcall is
1565 	 * sending us a response in an expected form
1566 	 */
1567 	if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
1568 		cifs_dbg(VFS, "incorrect version of cifs.upcall (expected %d but got %d)\n",
1569 			 CIFS_SPNEGO_UPCALL_VERSION, msg->version);
1570 		rc = -EKEYREJECTED;
1571 		goto out_put_spnego_key;
1572 	}
1573 
1574 	kfree_sensitive(ses->auth_key.response);
1575 	ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
1576 					 GFP_KERNEL);
1577 	if (!ses->auth_key.response) {
1578 		cifs_dbg(VFS, "Kerberos can't allocate (%u bytes) memory\n",
1579 			 msg->sesskey_len);
1580 		rc = -ENOMEM;
1581 		goto out_put_spnego_key;
1582 	}
1583 	ses->auth_key.len = msg->sesskey_len;
1584 
1585 	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
1586 	capabilities |= CAP_EXTENDED_SECURITY;
1587 	pSMB->req.Capabilities = cpu_to_le32(capabilities);
1588 	sess_data->iov[1].iov_base = msg->data + msg->sesskey_len;
1589 	sess_data->iov[1].iov_len = msg->secblob_len;
1590 	pSMB->req.SecurityBlobLength = cpu_to_le16(sess_data->iov[1].iov_len);
1591 
1592 	if (ses->capabilities & CAP_UNICODE) {
1593 		/* unicode strings must be word aligned */
1594 		if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
1595 			*bcc_ptr = 0;
1596 			bcc_ptr++;
1597 		}
1598 		unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1599 		unicode_domain_string(&bcc_ptr, ses, sess_data->nls_cp);
1600 	} else {
1601 		/* BB: is this right? */
1602 		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1603 	}
1604 
1605 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1606 			(long) sess_data->iov[2].iov_base;
1607 
1608 	rc = sess_sendreceive(sess_data);
1609 	if (rc)
1610 		goto out_put_spnego_key;
1611 
1612 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1613 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1614 
1615 	if (smb_buf->WordCount != 4) {
1616 		rc = -EIO;
1617 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1618 		goto out_put_spnego_key;
1619 	}
1620 
1621 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1622 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1623 
1624 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1625 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1626 
1627 	bytes_remaining = get_bcc(smb_buf);
1628 	bcc_ptr = pByteArea(smb_buf);
1629 
1630 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1631 	if (blob_len > bytes_remaining) {
1632 		cifs_dbg(VFS, "bad security blob length %d\n",
1633 				blob_len);
1634 		rc = -EINVAL;
1635 		goto out_put_spnego_key;
1636 	}
1637 	bcc_ptr += blob_len;
1638 	bytes_remaining -= blob_len;
1639 
1640 	/* BB check if Unicode and decode strings */
1641 	if (bytes_remaining == 0) {
1642 		/* no string area to decode, do nothing */
1643 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1644 		/* unicode string area must be word-aligned */
1645 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1646 			++bcc_ptr;
1647 			--bytes_remaining;
1648 		}
1649 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1650 				      sess_data->nls_cp);
1651 	} else {
1652 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1653 				    sess_data->nls_cp);
1654 	}
1655 
1656 	rc = sess_establish_session(sess_data);
1657 out_put_spnego_key:
1658 	key_invalidate(spnego_key);
1659 	key_put(spnego_key);
1660 out:
1661 	sess_data->result = rc;
1662 	sess_data->func = NULL;
1663 	sess_free_buffer(sess_data);
1664 	kfree_sensitive(ses->auth_key.response);
1665 	ses->auth_key.response = NULL;
1666 }
1667 
1668 #endif /* ! CONFIG_CIFS_UPCALL */
1669 
1670 /*
1671  * The required kvec buffers have to be allocated before calling this
1672  * function.
1673  */
1674 static int
1675 _sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
1676 {
1677 	SESSION_SETUP_ANDX *pSMB;
1678 	struct cifs_ses *ses = sess_data->ses;
1679 	struct TCP_Server_Info *server = sess_data->server;
1680 	__u32 capabilities;
1681 	char *bcc_ptr;
1682 
1683 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1684 
1685 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1686 	if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
1687 		cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
1688 		return -ENOSYS;
1689 	}
1690 
1691 	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
1692 	capabilities |= CAP_EXTENDED_SECURITY;
1693 	pSMB->req.Capabilities |= cpu_to_le32(capabilities);
1694 
1695 	bcc_ptr = sess_data->iov[2].iov_base;
1696 	/* unicode strings must be word aligned */
1697 	if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
1698 		*bcc_ptr = 0;
1699 		bcc_ptr++;
1700 	}
1701 	unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1702 
1703 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1704 					(long) sess_data->iov[2].iov_base;
1705 
1706 	return 0;
1707 }
1708 
1709 static void
1710 sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data);
1711 
1712 static void
1713 sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
1714 {
1715 	int rc;
1716 	struct smb_hdr *smb_buf;
1717 	SESSION_SETUP_ANDX *pSMB;
1718 	struct cifs_ses *ses = sess_data->ses;
1719 	struct TCP_Server_Info *server = sess_data->server;
1720 	__u16 bytes_remaining;
1721 	char *bcc_ptr;
1722 	unsigned char *ntlmsspblob = NULL;
1723 	u16 blob_len;
1724 
1725 	cifs_dbg(FYI, "rawntlmssp session setup negotiate phase\n");
1726 
1727 	/*
1728 	 * if memory allocation is successful, caller of this function
1729 	 * frees it.
1730 	 */
1731 	ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
1732 	if (!ses->ntlmssp) {
1733 		rc = -ENOMEM;
1734 		goto out;
1735 	}
1736 	ses->ntlmssp->sesskey_per_smbsess = false;
1737 
1738 	/* wct = 12 */
1739 	rc = sess_alloc_buffer(sess_data, 12);
1740 	if (rc)
1741 		goto out;
1742 
1743 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1744 
1745 	/* Build security blob before we assemble the request */
1746 	rc = build_ntlmssp_negotiate_blob(&ntlmsspblob,
1747 				     &blob_len, ses, server,
1748 				     sess_data->nls_cp);
1749 	if (rc)
1750 		goto out_free_ntlmsspblob;
1751 
1752 	sess_data->iov[1].iov_len = blob_len;
1753 	sess_data->iov[1].iov_base = ntlmsspblob;
1754 	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
1755 
1756 	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
1757 	if (rc)
1758 		goto out_free_ntlmsspblob;
1759 
1760 	rc = sess_sendreceive(sess_data);
1761 
1762 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1763 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1764 
1765 	/* If true, rc here is expected and not an error */
1766 	if (sess_data->buf0_type != CIFS_NO_BUFFER &&
1767 	    smb_buf->Status.CifsError ==
1768 			cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))
1769 		rc = 0;
1770 
1771 	if (rc)
1772 		goto out_free_ntlmsspblob;
1773 
1774 	cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n");
1775 
1776 	if (smb_buf->WordCount != 4) {
1777 		rc = -EIO;
1778 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1779 		goto out_free_ntlmsspblob;
1780 	}
1781 
1782 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1783 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1784 
1785 	bytes_remaining = get_bcc(smb_buf);
1786 	bcc_ptr = pByteArea(smb_buf);
1787 
1788 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1789 	if (blob_len > bytes_remaining) {
1790 		cifs_dbg(VFS, "bad security blob length %d\n",
1791 				blob_len);
1792 		rc = -EINVAL;
1793 		goto out_free_ntlmsspblob;
1794 	}
1795 
1796 	rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
1797 
1798 out_free_ntlmsspblob:
1799 	kfree_sensitive(ntlmsspblob);
1800 out:
1801 	sess_free_buffer(sess_data);
1802 
1803 	if (!rc) {
1804 		sess_data->func = sess_auth_rawntlmssp_authenticate;
1805 		return;
1806 	}
1807 
1808 	/* Else error. Cleanup */
1809 	kfree_sensitive(ses->auth_key.response);
1810 	ses->auth_key.response = NULL;
1811 	kfree_sensitive(ses->ntlmssp);
1812 	ses->ntlmssp = NULL;
1813 
1814 	sess_data->func = NULL;
1815 	sess_data->result = rc;
1816 }
1817 
1818 static void
1819 sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
1820 {
1821 	int rc;
1822 	struct smb_hdr *smb_buf;
1823 	SESSION_SETUP_ANDX *pSMB;
1824 	struct cifs_ses *ses = sess_data->ses;
1825 	struct TCP_Server_Info *server = sess_data->server;
1826 	__u16 bytes_remaining;
1827 	char *bcc_ptr;
1828 	unsigned char *ntlmsspblob = NULL;
1829 	u16 blob_len;
1830 
1831 	cifs_dbg(FYI, "rawntlmssp session setup authenticate phase\n");
1832 
1833 	/* wct = 12 */
1834 	rc = sess_alloc_buffer(sess_data, 12);
1835 	if (rc)
1836 		goto out;
1837 
1838 	/* Build security blob before we assemble the request */
1839 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1840 	smb_buf = (struct smb_hdr *)pSMB;
1841 	rc = build_ntlmssp_auth_blob(&ntlmsspblob,
1842 					&blob_len, ses, server,
1843 					sess_data->nls_cp);
1844 	if (rc)
1845 		goto out_free_ntlmsspblob;
1846 	sess_data->iov[1].iov_len = blob_len;
1847 	sess_data->iov[1].iov_base = ntlmsspblob;
1848 	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
1849 	/*
1850 	 * Make sure that we tell the server that we are using
1851 	 * the uid that it just gave us back on the response
1852 	 * (challenge)
1853 	 */
1854 	smb_buf->Uid = ses->Suid;
1855 
1856 	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
1857 	if (rc)
1858 		goto out_free_ntlmsspblob;
1859 
1860 	rc = sess_sendreceive(sess_data);
1861 	if (rc)
1862 		goto out_free_ntlmsspblob;
1863 
1864 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1865 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1866 	if (smb_buf->WordCount != 4) {
1867 		rc = -EIO;
1868 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1869 		goto out_free_ntlmsspblob;
1870 	}
1871 
1872 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1873 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1874 
1875 	if (ses->Suid != smb_buf->Uid) {
1876 		ses->Suid = smb_buf->Uid;
1877 		cifs_dbg(FYI, "UID changed! new UID = %llu\n", ses->Suid);
1878 	}
1879 
1880 	bytes_remaining = get_bcc(smb_buf);
1881 	bcc_ptr = pByteArea(smb_buf);
1882 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1883 	if (blob_len > bytes_remaining) {
1884 		cifs_dbg(VFS, "bad security blob length %d\n",
1885 				blob_len);
1886 		rc = -EINVAL;
1887 		goto out_free_ntlmsspblob;
1888 	}
1889 	bcc_ptr += blob_len;
1890 	bytes_remaining -= blob_len;
1891 
1892 
1893 	/* BB check if Unicode and decode strings */
1894 	if (bytes_remaining == 0) {
1895 		/* no string area to decode, do nothing */
1896 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1897 		/* unicode string area must be word-aligned */
1898 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1899 			++bcc_ptr;
1900 			--bytes_remaining;
1901 		}
1902 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1903 				      sess_data->nls_cp);
1904 	} else {
1905 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1906 				    sess_data->nls_cp);
1907 	}
1908 
1909 out_free_ntlmsspblob:
1910 	kfree_sensitive(ntlmsspblob);
1911 out:
1912 	sess_free_buffer(sess_data);
1913 
1914 	if (!rc)
1915 		rc = sess_establish_session(sess_data);
1916 
1917 	/* Cleanup */
1918 	kfree_sensitive(ses->auth_key.response);
1919 	ses->auth_key.response = NULL;
1920 	kfree_sensitive(ses->ntlmssp);
1921 	ses->ntlmssp = NULL;
1922 
1923 	sess_data->func = NULL;
1924 	sess_data->result = rc;
1925 }
1926 
1927 static int select_sec(struct sess_data *sess_data)
1928 {
1929 	int type;
1930 	struct cifs_ses *ses = sess_data->ses;
1931 	struct TCP_Server_Info *server = sess_data->server;
1932 
1933 	type = cifs_select_sectype(server, ses->sectype);
1934 	cifs_dbg(FYI, "sess setup type %d\n", type);
1935 	if (type == Unspecified) {
1936 		cifs_dbg(VFS, "Unable to select appropriate authentication method!\n");
1937 		return -EINVAL;
1938 	}
1939 
1940 	switch (type) {
1941 	case NTLMv2:
1942 		sess_data->func = sess_auth_ntlmv2;
1943 		break;
1944 	case Kerberos:
1945 #ifdef CONFIG_CIFS_UPCALL
1946 		sess_data->func = sess_auth_kerberos;
1947 		break;
1948 #else
1949 		cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
1950 		return -ENOSYS;
1951 #endif /* CONFIG_CIFS_UPCALL */
1952 	case RawNTLMSSP:
1953 		sess_data->func = sess_auth_rawntlmssp_negotiate;
1954 		break;
1955 	default:
1956 		cifs_dbg(VFS, "secType %d not supported!\n", type);
1957 		return -ENOSYS;
1958 	}
1959 
1960 	return 0;
1961 }
1962 
1963 int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
1964 		   struct TCP_Server_Info *server,
1965 		   const struct nls_table *nls_cp)
1966 {
1967 	int rc = 0;
1968 	struct sess_data *sess_data;
1969 
1970 	if (ses == NULL) {
1971 		WARN(1, "%s: ses == NULL!", __func__);
1972 		return -EINVAL;
1973 	}
1974 
1975 	sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
1976 	if (!sess_data)
1977 		return -ENOMEM;
1978 
1979 	sess_data->xid = xid;
1980 	sess_data->ses = ses;
1981 	sess_data->server = server;
1982 	sess_data->buf0_type = CIFS_NO_BUFFER;
1983 	sess_data->nls_cp = (struct nls_table *) nls_cp;
1984 
1985 	rc = select_sec(sess_data);
1986 	if (rc)
1987 		goto out;
1988 
1989 	while (sess_data->func)
1990 		sess_data->func(sess_data);
1991 
1992 	/* Store result before we free sess_data */
1993 	rc = sess_data->result;
1994 
1995 out:
1996 	kfree_sensitive(sess_data);
1997 	return rc;
1998 }
1999 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
2000