xref: /openbmc/linux/fs/smb/client/sess.c (revision 3dfbe6a73ae80429ccd268749e91c0d8d1526107)
1 // SPDX-License-Identifier: LGPL-2.1
2 /*
3  *
4  *   SMB/CIFS session setup handling routines
5  *
6  *   Copyright (c) International Business Machines  Corp., 2006, 2009
7  *   Author(s): Steve French (sfrench@us.ibm.com)
8  *
9  */
10 
11 #include "cifspdu.h"
12 #include "cifsglob.h"
13 #include "cifsproto.h"
14 #include "cifs_unicode.h"
15 #include "cifs_debug.h"
16 #include "ntlmssp.h"
17 #include "nterr.h"
18 #include <linux/utsname.h>
19 #include <linux/slab.h>
20 #include <linux/version.h>
21 #include "cifsfs.h"
22 #include "cifs_spnego.h"
23 #include "smb2proto.h"
24 #include "fs_context.h"
25 
26 static int
27 cifs_ses_add_channel(struct cifs_ses *ses,
28 		     struct cifs_server_iface *iface);
29 
30 bool
is_server_using_iface(struct TCP_Server_Info * server,struct cifs_server_iface * iface)31 is_server_using_iface(struct TCP_Server_Info *server,
32 		      struct cifs_server_iface *iface)
33 {
34 	struct sockaddr_in *i4 = (struct sockaddr_in *)&iface->sockaddr;
35 	struct sockaddr_in6 *i6 = (struct sockaddr_in6 *)&iface->sockaddr;
36 	struct sockaddr_in *s4 = (struct sockaddr_in *)&server->dstaddr;
37 	struct sockaddr_in6 *s6 = (struct sockaddr_in6 *)&server->dstaddr;
38 
39 	if (server->dstaddr.ss_family != iface->sockaddr.ss_family)
40 		return false;
41 	if (server->dstaddr.ss_family == AF_INET) {
42 		if (s4->sin_addr.s_addr != i4->sin_addr.s_addr)
43 			return false;
44 	} else if (server->dstaddr.ss_family == AF_INET6) {
45 		if (memcmp(&s6->sin6_addr, &i6->sin6_addr,
46 			   sizeof(i6->sin6_addr)) != 0)
47 			return false;
48 	} else {
49 		/* unknown family.. */
50 		return false;
51 	}
52 	return true;
53 }
54 
is_ses_using_iface(struct cifs_ses * ses,struct cifs_server_iface * iface)55 bool is_ses_using_iface(struct cifs_ses *ses, struct cifs_server_iface *iface)
56 {
57 	int i;
58 
59 	spin_lock(&ses->chan_lock);
60 	for (i = 0; i < ses->chan_count; i++) {
61 		if (ses->chans[i].iface == iface) {
62 			spin_unlock(&ses->chan_lock);
63 			return true;
64 		}
65 	}
66 	spin_unlock(&ses->chan_lock);
67 	return false;
68 }
69 
70 /* channel helper functions. assumed that chan_lock is held by caller. */
71 
72 int
cifs_ses_get_chan_index(struct cifs_ses * ses,struct TCP_Server_Info * server)73 cifs_ses_get_chan_index(struct cifs_ses *ses,
74 			struct TCP_Server_Info *server)
75 {
76 	unsigned int i;
77 
78 	/* if the channel is waiting for termination */
79 	if (server && server->terminate)
80 		return CIFS_INVAL_CHAN_INDEX;
81 
82 	for (i = 0; i < ses->chan_count; i++) {
83 		if (ses->chans[i].server == server)
84 			return i;
85 	}
86 
87 	/* If we didn't find the channel, it is likely a bug */
88 	if (server)
89 		cifs_dbg(VFS, "unable to get chan index for server: 0x%llx",
90 			 server->conn_id);
91 	return CIFS_INVAL_CHAN_INDEX;
92 }
93 
94 void
cifs_chan_set_in_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)95 cifs_chan_set_in_reconnect(struct cifs_ses *ses,
96 			     struct TCP_Server_Info *server)
97 {
98 	int chan_index = cifs_ses_get_chan_index(ses, server);
99 
100 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
101 		return;
102 
103 	ses->chans[chan_index].in_reconnect = true;
104 }
105 
106 void
cifs_chan_clear_in_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)107 cifs_chan_clear_in_reconnect(struct cifs_ses *ses,
108 			     struct TCP_Server_Info *server)
109 {
110 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
111 
112 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
113 		return;
114 
115 	ses->chans[chan_index].in_reconnect = false;
116 }
117 
118 bool
cifs_chan_in_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)119 cifs_chan_in_reconnect(struct cifs_ses *ses,
120 			  struct TCP_Server_Info *server)
121 {
122 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
123 
124 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
125 		return true;	/* err on the safer side */
126 
127 	return CIFS_CHAN_IN_RECONNECT(ses, chan_index);
128 }
129 
130 void
cifs_chan_set_need_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)131 cifs_chan_set_need_reconnect(struct cifs_ses *ses,
132 			     struct TCP_Server_Info *server)
133 {
134 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
135 
136 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
137 		return;
138 
139 	set_bit(chan_index, &ses->chans_need_reconnect);
140 	cifs_dbg(FYI, "Set reconnect bitmask for chan %u; now 0x%lx\n",
141 		 chan_index, ses->chans_need_reconnect);
142 }
143 
144 void
cifs_chan_clear_need_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)145 cifs_chan_clear_need_reconnect(struct cifs_ses *ses,
146 			       struct TCP_Server_Info *server)
147 {
148 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
149 
150 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
151 		return;
152 
153 	clear_bit(chan_index, &ses->chans_need_reconnect);
154 	cifs_dbg(FYI, "Cleared reconnect bitmask for chan %u; now 0x%lx\n",
155 		 chan_index, ses->chans_need_reconnect);
156 }
157 
158 bool
cifs_chan_needs_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)159 cifs_chan_needs_reconnect(struct cifs_ses *ses,
160 			  struct TCP_Server_Info *server)
161 {
162 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
163 
164 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
165 		return true;	/* err on the safer side */
166 
167 	return CIFS_CHAN_NEEDS_RECONNECT(ses, chan_index);
168 }
169 
170 bool
cifs_chan_is_iface_active(struct cifs_ses * ses,struct TCP_Server_Info * server)171 cifs_chan_is_iface_active(struct cifs_ses *ses,
172 			  struct TCP_Server_Info *server)
173 {
174 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
175 
176 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
177 		return true;	/* err on the safer side */
178 
179 	return ses->chans[chan_index].iface &&
180 		ses->chans[chan_index].iface->is_active;
181 }
182 
183 /* returns number of channels added */
cifs_try_adding_channels(struct cifs_ses * ses)184 int cifs_try_adding_channels(struct cifs_ses *ses)
185 {
186 	struct TCP_Server_Info *server = ses->server;
187 	int old_chan_count, new_chan_count;
188 	int left;
189 	int rc = 0;
190 	int tries = 0;
191 	size_t iface_weight = 0, iface_min_speed = 0;
192 	struct cifs_server_iface *iface = NULL, *niface = NULL;
193 	struct cifs_server_iface *last_iface = NULL;
194 
195 	spin_lock(&ses->chan_lock);
196 
197 	new_chan_count = old_chan_count = ses->chan_count;
198 	left = ses->chan_max - ses->chan_count;
199 
200 	if (left <= 0) {
201 		spin_unlock(&ses->chan_lock);
202 		cifs_dbg(FYI,
203 			 "ses already at max_channels (%zu), nothing to open\n",
204 			 ses->chan_max);
205 		return 0;
206 	}
207 
208 	if (server->dialect < SMB30_PROT_ID) {
209 		spin_unlock(&ses->chan_lock);
210 		cifs_dbg(VFS, "multichannel is not supported on this protocol version, use 3.0 or above\n");
211 		return 0;
212 	}
213 
214 	if (!(server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
215 		spin_unlock(&ses->chan_lock);
216 		cifs_server_dbg(VFS, "no multichannel support\n");
217 		return 0;
218 	}
219 	spin_unlock(&ses->chan_lock);
220 
221 	while (left > 0) {
222 
223 		tries++;
224 		if (tries > 3*ses->chan_max) {
225 			cifs_dbg(VFS, "too many channel open attempts (%d channels left to open)\n",
226 				 left);
227 			break;
228 		}
229 
230 		spin_lock(&ses->iface_lock);
231 		if (!ses->iface_count) {
232 			spin_unlock(&ses->iface_lock);
233 			cifs_dbg(ONCE, "server %s does not advertise interfaces\n",
234 				      ses->server->hostname);
235 			break;
236 		}
237 
238 		if (!iface)
239 			iface = list_first_entry(&ses->iface_list, struct cifs_server_iface,
240 						 iface_head);
241 		last_iface = list_last_entry(&ses->iface_list, struct cifs_server_iface,
242 					     iface_head);
243 		iface_min_speed = last_iface->speed;
244 
245 		list_for_each_entry_safe_from(iface, niface, &ses->iface_list,
246 				    iface_head) {
247 			/* do not mix rdma and non-rdma interfaces */
248 			if (iface->rdma_capable != ses->server->rdma)
249 				continue;
250 
251 			/* skip ifaces that are unusable */
252 			if (!iface->is_active ||
253 			    (is_ses_using_iface(ses, iface) &&
254 			     !iface->rss_capable))
255 				continue;
256 
257 			/* check if we already allocated enough channels */
258 			iface_weight = iface->speed / iface_min_speed;
259 
260 			if (iface->weight_fulfilled >= iface_weight)
261 				continue;
262 
263 			/* take ref before unlock */
264 			kref_get(&iface->refcount);
265 
266 			spin_unlock(&ses->iface_lock);
267 			rc = cifs_ses_add_channel(ses, iface);
268 			spin_lock(&ses->iface_lock);
269 
270 			if (rc) {
271 				cifs_dbg(VFS, "failed to open extra channel on iface:%pIS rc=%d\n",
272 					 &iface->sockaddr,
273 					 rc);
274 				kref_put(&iface->refcount, release_iface);
275 				/* failure to add chan should increase weight */
276 				iface->weight_fulfilled++;
277 				continue;
278 			}
279 
280 			iface->num_channels++;
281 			iface->weight_fulfilled++;
282 			cifs_dbg(VFS, "successfully opened new channel on iface:%pIS\n",
283 				 &iface->sockaddr);
284 			break;
285 		}
286 
287 		/* reached end of list. reset weight_fulfilled and start over */
288 		if (list_entry_is_head(iface, &ses->iface_list, iface_head)) {
289 			list_for_each_entry(iface, &ses->iface_list, iface_head)
290 				iface->weight_fulfilled = 0;
291 			spin_unlock(&ses->iface_lock);
292 			iface = NULL;
293 			continue;
294 		}
295 		spin_unlock(&ses->iface_lock);
296 
297 		left--;
298 		new_chan_count++;
299 	}
300 
301 	return new_chan_count - old_chan_count;
302 }
303 
304 /*
305  * called when multichannel is disabled by the server.
306  * this always gets called from smb2_reconnect
307  * and cannot get called in parallel threads.
308  */
309 void
cifs_disable_secondary_channels(struct cifs_ses * ses)310 cifs_disable_secondary_channels(struct cifs_ses *ses)
311 {
312 	int i, chan_count;
313 	struct TCP_Server_Info *server;
314 	struct cifs_server_iface *iface;
315 
316 	spin_lock(&ses->chan_lock);
317 	chan_count = ses->chan_count;
318 	if (chan_count == 1)
319 		goto done;
320 
321 	ses->chan_count = 1;
322 
323 	/* for all secondary channels reset the need reconnect bit */
324 	ses->chans_need_reconnect &= 1;
325 
326 	for (i = 1; i < chan_count; i++) {
327 		iface = ses->chans[i].iface;
328 		server = ses->chans[i].server;
329 
330 		/*
331 		 * remove these references first, since we need to unlock
332 		 * the chan_lock here, since iface_lock is a higher lock
333 		 */
334 		ses->chans[i].iface = NULL;
335 		ses->chans[i].server = NULL;
336 		spin_unlock(&ses->chan_lock);
337 
338 		if (iface) {
339 			spin_lock(&ses->iface_lock);
340 			iface->num_channels--;
341 			if (iface->weight_fulfilled)
342 				iface->weight_fulfilled--;
343 			kref_put(&iface->refcount, release_iface);
344 			spin_unlock(&ses->iface_lock);
345 		}
346 
347 		if (server) {
348 			if (!server->terminate) {
349 				server->terminate = true;
350 				cifs_signal_cifsd_for_reconnect(server, false);
351 			}
352 			cifs_put_tcp_session(server, false);
353 		}
354 
355 		spin_lock(&ses->chan_lock);
356 	}
357 
358 done:
359 	spin_unlock(&ses->chan_lock);
360 }
361 
362 /*
363  * update the iface for the channel if necessary.
364  * Must be called with chan_lock held.
365  */
366 void
cifs_chan_update_iface(struct cifs_ses * ses,struct TCP_Server_Info * server)367 cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
368 {
369 	unsigned int chan_index;
370 	size_t iface_weight = 0, iface_min_speed = 0;
371 	struct cifs_server_iface *iface = NULL;
372 	struct cifs_server_iface *old_iface = NULL;
373 	struct cifs_server_iface *last_iface = NULL;
374 	struct sockaddr_storage ss;
375 
376 	spin_lock(&ses->chan_lock);
377 	chan_index = cifs_ses_get_chan_index(ses, server);
378 	if (chan_index == CIFS_INVAL_CHAN_INDEX) {
379 		spin_unlock(&ses->chan_lock);
380 		return;
381 	}
382 
383 	if (ses->chans[chan_index].iface) {
384 		old_iface = ses->chans[chan_index].iface;
385 		if (old_iface->is_active) {
386 			spin_unlock(&ses->chan_lock);
387 			return;
388 		}
389 	}
390 	spin_unlock(&ses->chan_lock);
391 
392 	spin_lock(&server->srv_lock);
393 	ss = server->dstaddr;
394 	spin_unlock(&server->srv_lock);
395 
396 	spin_lock(&ses->iface_lock);
397 	if (!ses->iface_count) {
398 		spin_unlock(&ses->iface_lock);
399 		cifs_dbg(ONCE, "server %s does not advertise interfaces\n", ses->server->hostname);
400 		return;
401 	}
402 
403 	last_iface = list_last_entry(&ses->iface_list, struct cifs_server_iface,
404 				     iface_head);
405 	iface_min_speed = last_iface->speed;
406 
407 	/* then look for a new one */
408 	list_for_each_entry(iface, &ses->iface_list, iface_head) {
409 		if (!chan_index) {
410 			/* if we're trying to get the updated iface for primary channel */
411 			if (!cifs_match_ipaddr((struct sockaddr *) &ss,
412 					       (struct sockaddr *) &iface->sockaddr))
413 				continue;
414 
415 			kref_get(&iface->refcount);
416 			break;
417 		}
418 
419 		/* do not mix rdma and non-rdma interfaces */
420 		if (iface->rdma_capable != server->rdma)
421 			continue;
422 
423 		if (!iface->is_active ||
424 		    (is_ses_using_iface(ses, iface) &&
425 		     !iface->rss_capable)) {
426 			continue;
427 		}
428 
429 		/* check if we already allocated enough channels */
430 		iface_weight = iface->speed / iface_min_speed;
431 
432 		if (iface->weight_fulfilled >= iface_weight)
433 			continue;
434 
435 		kref_get(&iface->refcount);
436 		break;
437 	}
438 
439 	if (list_entry_is_head(iface, &ses->iface_list, iface_head)) {
440 		iface = NULL;
441 		cifs_dbg(FYI, "unable to find a suitable iface\n");
442 	}
443 
444 	if (!iface) {
445 		if (!chan_index)
446 			cifs_dbg(FYI, "unable to get the interface matching: %pIS\n",
447 				 &ss);
448 		else {
449 			cifs_dbg(FYI, "unable to find another interface to replace: %pIS\n",
450 				 &old_iface->sockaddr);
451 		}
452 
453 		spin_unlock(&ses->iface_lock);
454 		return;
455 	}
456 
457 	/* now drop the ref to the current iface */
458 	if (old_iface) {
459 		cifs_dbg(FYI, "replacing iface: %pIS with %pIS\n",
460 			 &old_iface->sockaddr,
461 			 &iface->sockaddr);
462 
463 		old_iface->num_channels--;
464 		if (old_iface->weight_fulfilled)
465 			old_iface->weight_fulfilled--;
466 		iface->num_channels++;
467 		iface->weight_fulfilled++;
468 
469 		kref_put(&old_iface->refcount, release_iface);
470 	} else if (!chan_index) {
471 		/* special case: update interface for primary channel */
472 		cifs_dbg(FYI, "referencing primary channel iface: %pIS\n",
473 			 &iface->sockaddr);
474 		iface->num_channels++;
475 		iface->weight_fulfilled++;
476 	}
477 	spin_unlock(&ses->iface_lock);
478 
479 	spin_lock(&ses->chan_lock);
480 	chan_index = cifs_ses_get_chan_index(ses, server);
481 	if (chan_index == CIFS_INVAL_CHAN_INDEX) {
482 		spin_unlock(&ses->chan_lock);
483 		return;
484 	}
485 
486 	ses->chans[chan_index].iface = iface;
487 	spin_unlock(&ses->chan_lock);
488 }
489 
490 /*
491  * If server is a channel of ses, return the corresponding enclosing
492  * cifs_chan otherwise return NULL.
493  */
494 struct cifs_chan *
cifs_ses_find_chan(struct cifs_ses * ses,struct TCP_Server_Info * server)495 cifs_ses_find_chan(struct cifs_ses *ses, struct TCP_Server_Info *server)
496 {
497 	int i;
498 
499 	spin_lock(&ses->chan_lock);
500 	for (i = 0; i < ses->chan_count; i++) {
501 		if (ses->chans[i].server == server) {
502 			spin_unlock(&ses->chan_lock);
503 			return &ses->chans[i];
504 		}
505 	}
506 	spin_unlock(&ses->chan_lock);
507 	return NULL;
508 }
509 
510 static int
cifs_ses_add_channel(struct cifs_ses * ses,struct cifs_server_iface * iface)511 cifs_ses_add_channel(struct cifs_ses *ses,
512 		     struct cifs_server_iface *iface)
513 {
514 	struct TCP_Server_Info *chan_server;
515 	struct cifs_chan *chan;
516 	struct smb3_fs_context *ctx;
517 	static const char unc_fmt[] = "\\%s\\foo";
518 	struct sockaddr_in *ipv4 = (struct sockaddr_in *)&iface->sockaddr;
519 	struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&iface->sockaddr;
520 	size_t len;
521 	int rc;
522 	unsigned int xid = get_xid();
523 
524 	if (iface->sockaddr.ss_family == AF_INET)
525 		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI4)\n",
526 			 ses, iface->speed, iface->rdma_capable ? "yes" : "no",
527 			 &ipv4->sin_addr);
528 	else
529 		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI6)\n",
530 			 ses, iface->speed, iface->rdma_capable ? "yes" : "no",
531 			 &ipv6->sin6_addr);
532 
533 	/*
534 	 * Setup a ctx with mostly the same info as the existing
535 	 * session and overwrite it with the requested iface data.
536 	 *
537 	 * We need to setup at least the fields used for negprot and
538 	 * sesssetup.
539 	 *
540 	 * We only need the ctx here, so we can reuse memory from
541 	 * the session and server without caring about memory
542 	 * management.
543 	 */
544 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
545 	if (!ctx) {
546 		rc = -ENOMEM;
547 		goto out_free_xid;
548 	}
549 
550 	/* Always make new connection for now (TODO?) */
551 	ctx->nosharesock = true;
552 
553 	/* Auth */
554 	ctx->domainauto = ses->domainAuto;
555 	ctx->domainname = ses->domainName;
556 
557 	/* no hostname for extra channels */
558 	ctx->server_hostname = "";
559 
560 	ctx->username = ses->user_name;
561 	ctx->password = ses->password;
562 	ctx->sectype = ses->sectype;
563 	ctx->sign = ses->sign;
564 
565 	/* UNC and paths */
566 	/* XXX: Use ses->server->hostname? */
567 	len = sizeof(unc_fmt) + SERVER_NAME_LEN_WITH_NULL;
568 	ctx->UNC = kzalloc(len, GFP_KERNEL);
569 	if (!ctx->UNC) {
570 		rc = -ENOMEM;
571 		goto out_free_ctx;
572 	}
573 	scnprintf(ctx->UNC, len, unc_fmt, ses->ip_addr);
574 	ctx->prepath = "";
575 
576 	/* Reuse same version as master connection */
577 	ctx->vals = ses->server->vals;
578 	ctx->ops = ses->server->ops;
579 
580 	ctx->noblocksnd = ses->server->noblocksnd;
581 	ctx->noautotune = ses->server->noautotune;
582 	ctx->sockopt_tcp_nodelay = ses->server->tcp_nodelay;
583 	ctx->echo_interval = ses->server->echo_interval / HZ;
584 	ctx->max_credits = ses->server->max_credits;
585 
586 	/*
587 	 * This will be used for encoding/decoding user/domain/pw
588 	 * during sess setup auth.
589 	 */
590 	ctx->local_nls = ses->local_nls;
591 
592 	/* Use RDMA if possible */
593 	ctx->rdma = iface->rdma_capable;
594 	memcpy(&ctx->dstaddr, &iface->sockaddr, sizeof(ctx->dstaddr));
595 
596 	/* reuse master con client guid */
597 	memcpy(&ctx->client_guid, ses->server->client_guid,
598 	       sizeof(ctx->client_guid));
599 	ctx->use_client_guid = true;
600 
601 	chan_server = cifs_get_tcp_session(ctx, ses->server);
602 
603 	spin_lock(&ses->chan_lock);
604 	chan = &ses->chans[ses->chan_count];
605 	chan->server = chan_server;
606 	if (IS_ERR(chan->server)) {
607 		rc = PTR_ERR(chan->server);
608 		chan->server = NULL;
609 		spin_unlock(&ses->chan_lock);
610 		goto out;
611 	}
612 	chan->iface = iface;
613 	ses->chan_count++;
614 	atomic_set(&ses->chan_seq, 0);
615 
616 	/* Mark this channel as needing connect/setup */
617 	cifs_chan_set_need_reconnect(ses, chan->server);
618 
619 	spin_unlock(&ses->chan_lock);
620 
621 	mutex_lock(&ses->session_mutex);
622 	/*
623 	 * We need to allocate the server crypto now as we will need
624 	 * to sign packets before we generate the channel signing key
625 	 * (we sign with the session key)
626 	 */
627 	rc = smb311_crypto_shash_allocate(chan->server);
628 	if (rc) {
629 		cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
630 		mutex_unlock(&ses->session_mutex);
631 		goto out;
632 	}
633 
634 	rc = cifs_negotiate_protocol(xid, ses, chan->server);
635 	if (!rc)
636 		rc = cifs_setup_session(xid, ses, chan->server, ses->local_nls);
637 
638 	mutex_unlock(&ses->session_mutex);
639 
640 out:
641 	if (rc && chan->server) {
642 		cifs_put_tcp_session(chan->server, 0);
643 
644 		spin_lock(&ses->chan_lock);
645 
646 		/* we rely on all bits beyond chan_count to be clear */
647 		cifs_chan_clear_need_reconnect(ses, chan->server);
648 		ses->chan_count--;
649 		/*
650 		 * chan_count should never reach 0 as at least the primary
651 		 * channel is always allocated
652 		 */
653 		WARN_ON(ses->chan_count < 1);
654 		spin_unlock(&ses->chan_lock);
655 	}
656 
657 	kfree(ctx->UNC);
658 out_free_ctx:
659 	kfree(ctx);
660 out_free_xid:
661 	free_xid(xid);
662 	return rc;
663 }
664 
665 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
cifs_ssetup_hdr(struct cifs_ses * ses,struct TCP_Server_Info * server,SESSION_SETUP_ANDX * pSMB)666 static __u32 cifs_ssetup_hdr(struct cifs_ses *ses,
667 			     struct TCP_Server_Info *server,
668 			     SESSION_SETUP_ANDX *pSMB)
669 {
670 	__u32 capabilities = 0;
671 
672 	/* init fields common to all four types of SessSetup */
673 	/* Note that offsets for first seven fields in req struct are same  */
674 	/*	in CIFS Specs so does not matter which of 3 forms of struct */
675 	/*	that we use in next few lines                               */
676 	/* Note that header is initialized to zero in header_assemble */
677 	pSMB->req.AndXCommand = 0xFF;
678 	pSMB->req.MaxBufferSize = cpu_to_le16(min_t(u32,
679 					CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4,
680 					USHRT_MAX));
681 	pSMB->req.MaxMpxCount = cpu_to_le16(server->maxReq);
682 	pSMB->req.VcNumber = cpu_to_le16(1);
683 
684 	/* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
685 
686 	/* BB verify whether signing required on neg or just auth frame (and NTLM case) */
687 
688 	capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
689 			CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
690 
691 	if (server->sign)
692 		pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
693 
694 	if (ses->capabilities & CAP_UNICODE) {
695 		pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
696 		capabilities |= CAP_UNICODE;
697 	}
698 	if (ses->capabilities & CAP_STATUS32) {
699 		pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
700 		capabilities |= CAP_STATUS32;
701 	}
702 	if (ses->capabilities & CAP_DFS) {
703 		pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
704 		capabilities |= CAP_DFS;
705 	}
706 	if (ses->capabilities & CAP_UNIX)
707 		capabilities |= CAP_UNIX;
708 
709 	return capabilities;
710 }
711 
712 static void
unicode_oslm_strings(char ** pbcc_area,const struct nls_table * nls_cp)713 unicode_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
714 {
715 	char *bcc_ptr = *pbcc_area;
716 	int bytes_ret = 0;
717 
718 	/* Copy OS version */
719 	bytes_ret = cifs_strtoUTF16((__le16 *)bcc_ptr, "Linux version ", 32,
720 				    nls_cp);
721 	bcc_ptr += 2 * bytes_ret;
722 	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, init_utsname()->release,
723 				    32, nls_cp);
724 	bcc_ptr += 2 * bytes_ret;
725 	bcc_ptr += 2; /* trailing null */
726 
727 	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
728 				    32, nls_cp);
729 	bcc_ptr += 2 * bytes_ret;
730 	bcc_ptr += 2; /* trailing null */
731 
732 	*pbcc_area = bcc_ptr;
733 }
734 
735 static void
ascii_oslm_strings(char ** pbcc_area,const struct nls_table * nls_cp)736 ascii_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
737 {
738 	char *bcc_ptr = *pbcc_area;
739 
740 	strcpy(bcc_ptr, "Linux version ");
741 	bcc_ptr += strlen("Linux version ");
742 	strcpy(bcc_ptr, init_utsname()->release);
743 	bcc_ptr += strlen(init_utsname()->release) + 1;
744 
745 	strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
746 	bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;
747 
748 	*pbcc_area = bcc_ptr;
749 }
750 
unicode_domain_string(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)751 static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
752 				   const struct nls_table *nls_cp)
753 {
754 	char *bcc_ptr = *pbcc_area;
755 	int bytes_ret = 0;
756 
757 	/* copy domain */
758 	if (ses->domainName == NULL) {
759 		/*
760 		 * Sending null domain better than using a bogus domain name (as
761 		 * we did briefly in 2.6.18) since server will use its default
762 		 */
763 		*bcc_ptr = 0;
764 		*(bcc_ptr+1) = 0;
765 		bytes_ret = 0;
766 	} else
767 		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
768 					    CIFS_MAX_DOMAINNAME_LEN, nls_cp);
769 	bcc_ptr += 2 * bytes_ret;
770 	bcc_ptr += 2;  /* account for null terminator */
771 
772 	*pbcc_area = bcc_ptr;
773 }
774 
ascii_domain_string(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)775 static void ascii_domain_string(char **pbcc_area, struct cifs_ses *ses,
776 				const struct nls_table *nls_cp)
777 {
778 	char *bcc_ptr = *pbcc_area;
779 	int len;
780 
781 	/* copy domain */
782 	if (ses->domainName != NULL) {
783 		len = strscpy(bcc_ptr, ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
784 		if (WARN_ON_ONCE(len < 0))
785 			len = CIFS_MAX_DOMAINNAME_LEN - 1;
786 		bcc_ptr += len;
787 	} /* else we send a null domain name so server will default to its own domain */
788 	*bcc_ptr = 0;
789 	bcc_ptr++;
790 
791 	*pbcc_area = bcc_ptr;
792 }
793 
unicode_ssetup_strings(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)794 static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
795 				   const struct nls_table *nls_cp)
796 {
797 	char *bcc_ptr = *pbcc_area;
798 	int bytes_ret = 0;
799 
800 	/* BB FIXME add check that strings less than 335 or will need to send as arrays */
801 
802 	/* copy user */
803 	if (ses->user_name == NULL) {
804 		/* null user mount */
805 		*bcc_ptr = 0;
806 		*(bcc_ptr+1) = 0;
807 	} else {
808 		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->user_name,
809 					    CIFS_MAX_USERNAME_LEN, nls_cp);
810 	}
811 	bcc_ptr += 2 * bytes_ret;
812 	bcc_ptr += 2; /* account for null termination */
813 
814 	unicode_domain_string(&bcc_ptr, ses, nls_cp);
815 	unicode_oslm_strings(&bcc_ptr, nls_cp);
816 
817 	*pbcc_area = bcc_ptr;
818 }
819 
ascii_ssetup_strings(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)820 static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
821 				 const struct nls_table *nls_cp)
822 {
823 	char *bcc_ptr = *pbcc_area;
824 	int len;
825 
826 	/* copy user */
827 	/* BB what about null user mounts - check that we do this BB */
828 	/* copy user */
829 	if (ses->user_name != NULL) {
830 		len = strscpy(bcc_ptr, ses->user_name, CIFS_MAX_USERNAME_LEN);
831 		if (WARN_ON_ONCE(len < 0))
832 			len = CIFS_MAX_USERNAME_LEN - 1;
833 		bcc_ptr += len;
834 	}
835 	/* else null user mount */
836 	*bcc_ptr = 0;
837 	bcc_ptr++; /* account for null termination */
838 
839 	/* BB check for overflow here */
840 
841 	ascii_domain_string(&bcc_ptr, ses, nls_cp);
842 	ascii_oslm_strings(&bcc_ptr, nls_cp);
843 
844 	*pbcc_area = bcc_ptr;
845 }
846 
847 static void
decode_unicode_ssetup(char ** pbcc_area,int bleft,struct cifs_ses * ses,const struct nls_table * nls_cp)848 decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifs_ses *ses,
849 		      const struct nls_table *nls_cp)
850 {
851 	int len;
852 	char *data = *pbcc_area;
853 
854 	cifs_dbg(FYI, "bleft %d\n", bleft);
855 
856 	kfree(ses->serverOS);
857 	ses->serverOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
858 	cifs_dbg(FYI, "serverOS=%s\n", ses->serverOS);
859 	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
860 	data += len;
861 	bleft -= len;
862 	if (bleft <= 0)
863 		return;
864 
865 	kfree(ses->serverNOS);
866 	ses->serverNOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
867 	cifs_dbg(FYI, "serverNOS=%s\n", ses->serverNOS);
868 	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
869 	data += len;
870 	bleft -= len;
871 	if (bleft <= 0)
872 		return;
873 
874 	kfree(ses->serverDomain);
875 	ses->serverDomain = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
876 	cifs_dbg(FYI, "serverDomain=%s\n", ses->serverDomain);
877 
878 	return;
879 }
880 
decode_ascii_ssetup(char ** pbcc_area,__u16 bleft,struct cifs_ses * ses,const struct nls_table * nls_cp)881 static void decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
882 				struct cifs_ses *ses,
883 				const struct nls_table *nls_cp)
884 {
885 	int len;
886 	char *bcc_ptr = *pbcc_area;
887 
888 	cifs_dbg(FYI, "decode sessetup ascii. bleft %d\n", bleft);
889 
890 	len = strnlen(bcc_ptr, bleft);
891 	if (len >= bleft)
892 		return;
893 
894 	kfree(ses->serverOS);
895 
896 	ses->serverOS = kmalloc(len + 1, GFP_KERNEL);
897 	if (ses->serverOS) {
898 		memcpy(ses->serverOS, bcc_ptr, len);
899 		ses->serverOS[len] = 0;
900 		if (strncmp(ses->serverOS, "OS/2", 4) == 0)
901 			cifs_dbg(FYI, "OS/2 server\n");
902 	}
903 
904 	bcc_ptr += len + 1;
905 	bleft -= len + 1;
906 
907 	len = strnlen(bcc_ptr, bleft);
908 	if (len >= bleft)
909 		return;
910 
911 	kfree(ses->serverNOS);
912 
913 	ses->serverNOS = kmalloc(len + 1, GFP_KERNEL);
914 	if (ses->serverNOS) {
915 		memcpy(ses->serverNOS, bcc_ptr, len);
916 		ses->serverNOS[len] = 0;
917 	}
918 
919 	bcc_ptr += len + 1;
920 	bleft -= len + 1;
921 
922 	len = strnlen(bcc_ptr, bleft);
923 	if (len > bleft)
924 		return;
925 
926 	/*
927 	 * No domain field in LANMAN case. Domain is
928 	 * returned by old servers in the SMB negprot response
929 	 *
930 	 * BB For newer servers which do not support Unicode,
931 	 * but thus do return domain here, we could add parsing
932 	 * for it later, but it is not very important
933 	 */
934 	cifs_dbg(FYI, "ascii: bytes left %d\n", bleft);
935 }
936 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
937 
decode_ntlmssp_challenge(char * bcc_ptr,int blob_len,struct cifs_ses * ses)938 int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
939 				    struct cifs_ses *ses)
940 {
941 	unsigned int tioffset; /* challenge message target info area */
942 	unsigned int tilen; /* challenge message target info area length  */
943 	CHALLENGE_MESSAGE *pblob = (CHALLENGE_MESSAGE *)bcc_ptr;
944 	__u32 server_flags;
945 
946 	if (blob_len < sizeof(CHALLENGE_MESSAGE)) {
947 		cifs_dbg(VFS, "challenge blob len %d too small\n", blob_len);
948 		return -EINVAL;
949 	}
950 
951 	if (memcmp(pblob->Signature, "NTLMSSP", 8)) {
952 		cifs_dbg(VFS, "blob signature incorrect %s\n",
953 			 pblob->Signature);
954 		return -EINVAL;
955 	}
956 	if (pblob->MessageType != NtLmChallenge) {
957 		cifs_dbg(VFS, "Incorrect message type %d\n",
958 			 pblob->MessageType);
959 		return -EINVAL;
960 	}
961 
962 	server_flags = le32_to_cpu(pblob->NegotiateFlags);
963 	cifs_dbg(FYI, "%s: negotiate=0x%08x challenge=0x%08x\n", __func__,
964 		 ses->ntlmssp->client_flags, server_flags);
965 
966 	if ((ses->ntlmssp->client_flags & (NTLMSSP_NEGOTIATE_SEAL | NTLMSSP_NEGOTIATE_SIGN)) &&
967 	    (!(server_flags & NTLMSSP_NEGOTIATE_56) && !(server_flags & NTLMSSP_NEGOTIATE_128))) {
968 		cifs_dbg(VFS, "%s: requested signing/encryption but server did not return either 56-bit or 128-bit session key size\n",
969 			 __func__);
970 		return -EINVAL;
971 	}
972 	if (!(server_flags & NTLMSSP_NEGOTIATE_NTLM) && !(server_flags & NTLMSSP_NEGOTIATE_EXTENDED_SEC)) {
973 		cifs_dbg(VFS, "%s: server does not seem to support either NTLMv1 or NTLMv2\n", __func__);
974 		return -EINVAL;
975 	}
976 	if (ses->server->sign && !(server_flags & NTLMSSP_NEGOTIATE_SIGN)) {
977 		cifs_dbg(VFS, "%s: forced packet signing but server does not seem to support it\n",
978 			 __func__);
979 		return -EOPNOTSUPP;
980 	}
981 	if ((ses->ntlmssp->client_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
982 	    !(server_flags & NTLMSSP_NEGOTIATE_KEY_XCH))
983 		pr_warn_once("%s: authentication has been weakened as server does not support key exchange\n",
984 			     __func__);
985 
986 	ses->ntlmssp->server_flags = server_flags;
987 
988 	memcpy(ses->ntlmssp->cryptkey, pblob->Challenge, CIFS_CRYPTO_KEY_SIZE);
989 	/*
990 	 * In particular we can examine sign flags
991 	 *
992 	 * BB spec says that if AvId field of MsvAvTimestamp is populated then
993 	 * we must set the MIC field of the AUTHENTICATE_MESSAGE
994 	 */
995 
996 	tioffset = le32_to_cpu(pblob->TargetInfoArray.BufferOffset);
997 	tilen = le16_to_cpu(pblob->TargetInfoArray.Length);
998 	if (tioffset > blob_len || tioffset + tilen > blob_len) {
999 		cifs_dbg(VFS, "tioffset + tilen too high %u + %u\n",
1000 			 tioffset, tilen);
1001 		return -EINVAL;
1002 	}
1003 	if (tilen) {
1004 		kfree_sensitive(ses->auth_key.response);
1005 		ses->auth_key.response = kmemdup(bcc_ptr + tioffset, tilen,
1006 						 GFP_KERNEL);
1007 		if (!ses->auth_key.response) {
1008 			cifs_dbg(VFS, "Challenge target info alloc failure\n");
1009 			return -ENOMEM;
1010 		}
1011 		ses->auth_key.len = tilen;
1012 	}
1013 
1014 	return 0;
1015 }
1016 
size_of_ntlmssp_blob(struct cifs_ses * ses,int base_size)1017 static int size_of_ntlmssp_blob(struct cifs_ses *ses, int base_size)
1018 {
1019 	int sz = base_size + ses->auth_key.len
1020 		- CIFS_SESS_KEY_SIZE + CIFS_CPHTXT_SIZE + 2;
1021 
1022 	if (ses->domainName)
1023 		sz += sizeof(__le16) * strnlen(ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
1024 	else
1025 		sz += sizeof(__le16);
1026 
1027 	if (ses->user_name)
1028 		sz += sizeof(__le16) * strnlen(ses->user_name, CIFS_MAX_USERNAME_LEN);
1029 	else
1030 		sz += sizeof(__le16);
1031 
1032 	if (ses->workstation_name[0])
1033 		sz += sizeof(__le16) * strnlen(ses->workstation_name,
1034 					       ntlmssp_workstation_name_size(ses));
1035 	else
1036 		sz += sizeof(__le16);
1037 
1038 	return sz;
1039 }
1040 
cifs_security_buffer_from_str(SECURITY_BUFFER * pbuf,char * str_value,int str_length,unsigned char * pstart,unsigned char ** pcur,const struct nls_table * nls_cp)1041 static inline void cifs_security_buffer_from_str(SECURITY_BUFFER *pbuf,
1042 						 char *str_value,
1043 						 int str_length,
1044 						 unsigned char *pstart,
1045 						 unsigned char **pcur,
1046 						 const struct nls_table *nls_cp)
1047 {
1048 	unsigned char *tmp = pstart;
1049 	int len;
1050 
1051 	if (!pbuf)
1052 		return;
1053 
1054 	if (!pcur)
1055 		pcur = &tmp;
1056 
1057 	if (!str_value) {
1058 		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
1059 		pbuf->Length = 0;
1060 		pbuf->MaximumLength = 0;
1061 		*pcur += sizeof(__le16);
1062 	} else {
1063 		len = cifs_strtoUTF16((__le16 *)*pcur,
1064 				      str_value,
1065 				      str_length,
1066 				      nls_cp);
1067 		len *= sizeof(__le16);
1068 		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
1069 		pbuf->Length = cpu_to_le16(len);
1070 		pbuf->MaximumLength = cpu_to_le16(len);
1071 		*pcur += len;
1072 	}
1073 }
1074 
1075 /* BB Move to ntlmssp.c eventually */
1076 
build_ntlmssp_negotiate_blob(unsigned char ** pbuffer,u16 * buflen,struct cifs_ses * ses,struct TCP_Server_Info * server,const struct nls_table * nls_cp)1077 int build_ntlmssp_negotiate_blob(unsigned char **pbuffer,
1078 				 u16 *buflen,
1079 				 struct cifs_ses *ses,
1080 				 struct TCP_Server_Info *server,
1081 				 const struct nls_table *nls_cp)
1082 {
1083 	int rc = 0;
1084 	NEGOTIATE_MESSAGE *sec_blob;
1085 	__u32 flags;
1086 	unsigned char *tmp;
1087 	int len;
1088 
1089 	len = size_of_ntlmssp_blob(ses, sizeof(NEGOTIATE_MESSAGE));
1090 	*pbuffer = kmalloc(len, GFP_KERNEL);
1091 	if (!*pbuffer) {
1092 		rc = -ENOMEM;
1093 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1094 		*buflen = 0;
1095 		goto setup_ntlm_neg_ret;
1096 	}
1097 	sec_blob = (NEGOTIATE_MESSAGE *)*pbuffer;
1098 
1099 	memset(*pbuffer, 0, sizeof(NEGOTIATE_MESSAGE));
1100 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1101 	sec_blob->MessageType = NtLmNegotiate;
1102 
1103 	/* BB is NTLMV2 session security format easier to use here? */
1104 	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
1105 		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
1106 		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
1107 		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
1108 		NTLMSSP_NEGOTIATE_SIGN;
1109 	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
1110 		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
1111 
1112 	tmp = *pbuffer + sizeof(NEGOTIATE_MESSAGE);
1113 	ses->ntlmssp->client_flags = flags;
1114 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1115 
1116 	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
1117 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1118 				      NULL,
1119 				      CIFS_MAX_DOMAINNAME_LEN,
1120 				      *pbuffer, &tmp,
1121 				      nls_cp);
1122 
1123 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1124 				      NULL,
1125 				      CIFS_MAX_WORKSTATION_LEN,
1126 				      *pbuffer, &tmp,
1127 				      nls_cp);
1128 
1129 	*buflen = tmp - *pbuffer;
1130 setup_ntlm_neg_ret:
1131 	return rc;
1132 }
1133 
1134 /*
1135  * Build ntlmssp blob with additional fields, such as version,
1136  * supported by modern servers. For safety limit to SMB3 or later
1137  * See notes in MS-NLMP Section 2.2.2.1 e.g.
1138  */
build_ntlmssp_smb3_negotiate_blob(unsigned char ** pbuffer,u16 * buflen,struct cifs_ses * ses,struct TCP_Server_Info * server,const struct nls_table * nls_cp)1139 int build_ntlmssp_smb3_negotiate_blob(unsigned char **pbuffer,
1140 				 u16 *buflen,
1141 				 struct cifs_ses *ses,
1142 				 struct TCP_Server_Info *server,
1143 				 const struct nls_table *nls_cp)
1144 {
1145 	int rc = 0;
1146 	struct negotiate_message *sec_blob;
1147 	__u32 flags;
1148 	unsigned char *tmp;
1149 	int len;
1150 
1151 	len = size_of_ntlmssp_blob(ses, sizeof(struct negotiate_message));
1152 	*pbuffer = kmalloc(len, GFP_KERNEL);
1153 	if (!*pbuffer) {
1154 		rc = -ENOMEM;
1155 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1156 		*buflen = 0;
1157 		goto setup_ntlm_smb3_neg_ret;
1158 	}
1159 	sec_blob = (struct negotiate_message *)*pbuffer;
1160 
1161 	memset(*pbuffer, 0, sizeof(struct negotiate_message));
1162 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1163 	sec_blob->MessageType = NtLmNegotiate;
1164 
1165 	/* BB is NTLMV2 session security format easier to use here? */
1166 	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
1167 		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
1168 		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
1169 		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
1170 		NTLMSSP_NEGOTIATE_SIGN | NTLMSSP_NEGOTIATE_VERSION;
1171 	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
1172 		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
1173 
1174 	sec_blob->Version.ProductMajorVersion = LINUX_VERSION_MAJOR;
1175 	sec_blob->Version.ProductMinorVersion = LINUX_VERSION_PATCHLEVEL;
1176 	sec_blob->Version.ProductBuild = cpu_to_le16(SMB3_PRODUCT_BUILD);
1177 	sec_blob->Version.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
1178 
1179 	tmp = *pbuffer + sizeof(struct negotiate_message);
1180 	ses->ntlmssp->client_flags = flags;
1181 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1182 
1183 	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
1184 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1185 				      NULL,
1186 				      CIFS_MAX_DOMAINNAME_LEN,
1187 				      *pbuffer, &tmp,
1188 				      nls_cp);
1189 
1190 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1191 				      NULL,
1192 				      CIFS_MAX_WORKSTATION_LEN,
1193 				      *pbuffer, &tmp,
1194 				      nls_cp);
1195 
1196 	*buflen = tmp - *pbuffer;
1197 setup_ntlm_smb3_neg_ret:
1198 	return rc;
1199 }
1200 
1201 
1202 /* See MS-NLMP 2.2.1.3 */
build_ntlmssp_auth_blob(unsigned char ** pbuffer,u16 * buflen,struct cifs_ses * ses,struct TCP_Server_Info * server,const struct nls_table * nls_cp)1203 int build_ntlmssp_auth_blob(unsigned char **pbuffer,
1204 					u16 *buflen,
1205 				   struct cifs_ses *ses,
1206 				   struct TCP_Server_Info *server,
1207 				   const struct nls_table *nls_cp)
1208 {
1209 	int rc;
1210 	AUTHENTICATE_MESSAGE *sec_blob;
1211 	__u32 flags;
1212 	unsigned char *tmp;
1213 	int len;
1214 
1215 	rc = setup_ntlmv2_rsp(ses, nls_cp);
1216 	if (rc) {
1217 		cifs_dbg(VFS, "Error %d during NTLMSSP authentication\n", rc);
1218 		*buflen = 0;
1219 		goto setup_ntlmv2_ret;
1220 	}
1221 
1222 	len = size_of_ntlmssp_blob(ses, sizeof(AUTHENTICATE_MESSAGE));
1223 	*pbuffer = kmalloc(len, GFP_KERNEL);
1224 	if (!*pbuffer) {
1225 		rc = -ENOMEM;
1226 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1227 		*buflen = 0;
1228 		goto setup_ntlmv2_ret;
1229 	}
1230 	sec_blob = (AUTHENTICATE_MESSAGE *)*pbuffer;
1231 
1232 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1233 	sec_blob->MessageType = NtLmAuthenticate;
1234 
1235 	/* send version information in ntlmssp authenticate also */
1236 	flags = ses->ntlmssp->server_flags | NTLMSSP_REQUEST_TARGET |
1237 		NTLMSSP_NEGOTIATE_TARGET_INFO | NTLMSSP_NEGOTIATE_VERSION |
1238 		NTLMSSP_NEGOTIATE_WORKSTATION_SUPPLIED;
1239 
1240 	sec_blob->Version.ProductMajorVersion = LINUX_VERSION_MAJOR;
1241 	sec_blob->Version.ProductMinorVersion = LINUX_VERSION_PATCHLEVEL;
1242 	sec_blob->Version.ProductBuild = cpu_to_le16(SMB3_PRODUCT_BUILD);
1243 	sec_blob->Version.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
1244 
1245 	tmp = *pbuffer + sizeof(AUTHENTICATE_MESSAGE);
1246 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1247 
1248 	sec_blob->LmChallengeResponse.BufferOffset =
1249 				cpu_to_le32(sizeof(AUTHENTICATE_MESSAGE));
1250 	sec_blob->LmChallengeResponse.Length = 0;
1251 	sec_blob->LmChallengeResponse.MaximumLength = 0;
1252 
1253 	sec_blob->NtChallengeResponse.BufferOffset =
1254 				cpu_to_le32(tmp - *pbuffer);
1255 	if (ses->user_name != NULL) {
1256 		memcpy(tmp, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
1257 				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1258 		tmp += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
1259 
1260 		sec_blob->NtChallengeResponse.Length =
1261 				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1262 		sec_blob->NtChallengeResponse.MaximumLength =
1263 				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1264 	} else {
1265 		/*
1266 		 * don't send an NT Response for anonymous access
1267 		 */
1268 		sec_blob->NtChallengeResponse.Length = 0;
1269 		sec_blob->NtChallengeResponse.MaximumLength = 0;
1270 	}
1271 
1272 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1273 				      ses->domainName,
1274 				      CIFS_MAX_DOMAINNAME_LEN,
1275 				      *pbuffer, &tmp,
1276 				      nls_cp);
1277 
1278 	cifs_security_buffer_from_str(&sec_blob->UserName,
1279 				      ses->user_name,
1280 				      CIFS_MAX_USERNAME_LEN,
1281 				      *pbuffer, &tmp,
1282 				      nls_cp);
1283 
1284 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1285 				      ses->workstation_name,
1286 				      ntlmssp_workstation_name_size(ses),
1287 				      *pbuffer, &tmp,
1288 				      nls_cp);
1289 
1290 	if ((ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
1291 	    (!ses->server->session_estab || ses->ntlmssp->sesskey_per_smbsess) &&
1292 	    !calc_seckey(ses)) {
1293 		memcpy(tmp, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
1294 		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
1295 		sec_blob->SessionKey.Length = cpu_to_le16(CIFS_CPHTXT_SIZE);
1296 		sec_blob->SessionKey.MaximumLength =
1297 				cpu_to_le16(CIFS_CPHTXT_SIZE);
1298 		tmp += CIFS_CPHTXT_SIZE;
1299 	} else {
1300 		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
1301 		sec_blob->SessionKey.Length = 0;
1302 		sec_blob->SessionKey.MaximumLength = 0;
1303 	}
1304 
1305 	*buflen = tmp - *pbuffer;
1306 setup_ntlmv2_ret:
1307 	return rc;
1308 }
1309 
1310 enum securityEnum
cifs_select_sectype(struct TCP_Server_Info * server,enum securityEnum requested)1311 cifs_select_sectype(struct TCP_Server_Info *server, enum securityEnum requested)
1312 {
1313 	switch (server->negflavor) {
1314 	case CIFS_NEGFLAVOR_EXTENDED:
1315 		switch (requested) {
1316 		case Kerberos:
1317 		case RawNTLMSSP:
1318 		case IAKerb:
1319 			return requested;
1320 		case Unspecified:
1321 			if (server->sec_ntlmssp &&
1322 			    (global_secflags & CIFSSEC_MAY_NTLMSSP))
1323 				return RawNTLMSSP;
1324 			if ((server->sec_kerberos || server->sec_mskerberos || server->sec_iakerb) &&
1325 			    (global_secflags & CIFSSEC_MAY_KRB5))
1326 				return Kerberos;
1327 			fallthrough;
1328 		default:
1329 			return Unspecified;
1330 		}
1331 	case CIFS_NEGFLAVOR_UNENCAP:
1332 		switch (requested) {
1333 		case NTLMv2:
1334 			return requested;
1335 		case Unspecified:
1336 			if (global_secflags & CIFSSEC_MAY_NTLMV2)
1337 				return NTLMv2;
1338 			break;
1339 		default:
1340 			break;
1341 		}
1342 		fallthrough;
1343 	default:
1344 		return Unspecified;
1345 	}
1346 }
1347 
1348 struct sess_data {
1349 	unsigned int xid;
1350 	struct cifs_ses *ses;
1351 	struct TCP_Server_Info *server;
1352 	struct nls_table *nls_cp;
1353 	void (*func)(struct sess_data *);
1354 	int result;
1355 
1356 	/* we will send the SMB in three pieces:
1357 	 * a fixed length beginning part, an optional
1358 	 * SPNEGO blob (which can be zero length), and a
1359 	 * last part which will include the strings
1360 	 * and rest of bcc area. This allows us to avoid
1361 	 * a large buffer 17K allocation
1362 	 */
1363 	int buf0_type;
1364 	struct kvec iov[3];
1365 };
1366 
1367 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
1368 static int
sess_alloc_buffer(struct sess_data * sess_data,int wct)1369 sess_alloc_buffer(struct sess_data *sess_data, int wct)
1370 {
1371 	int rc;
1372 	struct cifs_ses *ses = sess_data->ses;
1373 	struct smb_hdr *smb_buf;
1374 
1375 	rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
1376 				  (void **)&smb_buf);
1377 
1378 	if (rc)
1379 		return rc;
1380 
1381 	sess_data->iov[0].iov_base = (char *)smb_buf;
1382 	sess_data->iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;
1383 	/*
1384 	 * This variable will be used to clear the buffer
1385 	 * allocated above in case of any error in the calling function.
1386 	 */
1387 	sess_data->buf0_type = CIFS_SMALL_BUFFER;
1388 
1389 	/* 2000 big enough to fit max user, domain, NOS name etc. */
1390 	sess_data->iov[2].iov_base = kmalloc(2000, GFP_KERNEL);
1391 	if (!sess_data->iov[2].iov_base) {
1392 		rc = -ENOMEM;
1393 		goto out_free_smb_buf;
1394 	}
1395 
1396 	return 0;
1397 
1398 out_free_smb_buf:
1399 	cifs_small_buf_release(smb_buf);
1400 	sess_data->iov[0].iov_base = NULL;
1401 	sess_data->iov[0].iov_len = 0;
1402 	sess_data->buf0_type = CIFS_NO_BUFFER;
1403 	return rc;
1404 }
1405 
1406 static void
sess_free_buffer(struct sess_data * sess_data)1407 sess_free_buffer(struct sess_data *sess_data)
1408 {
1409 	struct kvec *iov = sess_data->iov;
1410 
1411 	/*
1412 	 * Zero the session data before freeing, as it might contain sensitive info (keys, etc).
1413 	 * Note that iov[1] is already freed by caller.
1414 	 */
1415 	if (sess_data->buf0_type != CIFS_NO_BUFFER && iov[0].iov_base)
1416 		memzero_explicit(iov[0].iov_base, iov[0].iov_len);
1417 
1418 	free_rsp_buf(sess_data->buf0_type, iov[0].iov_base);
1419 	sess_data->buf0_type = CIFS_NO_BUFFER;
1420 	kfree_sensitive(iov[2].iov_base);
1421 }
1422 
1423 static int
sess_establish_session(struct sess_data * sess_data)1424 sess_establish_session(struct sess_data *sess_data)
1425 {
1426 	struct cifs_ses *ses = sess_data->ses;
1427 	struct TCP_Server_Info *server = sess_data->server;
1428 
1429 	cifs_server_lock(server);
1430 	if (!server->session_estab) {
1431 		if (server->sign) {
1432 			server->session_key.response =
1433 				kmemdup(ses->auth_key.response,
1434 				ses->auth_key.len, GFP_KERNEL);
1435 			if (!server->session_key.response) {
1436 				cifs_server_unlock(server);
1437 				return -ENOMEM;
1438 			}
1439 			server->session_key.len =
1440 						ses->auth_key.len;
1441 		}
1442 		server->sequence_number = 0x2;
1443 		server->session_estab = true;
1444 	}
1445 	cifs_server_unlock(server);
1446 
1447 	cifs_dbg(FYI, "CIFS session established successfully\n");
1448 	return 0;
1449 }
1450 
1451 static int
sess_sendreceive(struct sess_data * sess_data)1452 sess_sendreceive(struct sess_data *sess_data)
1453 {
1454 	int rc;
1455 	struct smb_hdr *smb_buf = (struct smb_hdr *) sess_data->iov[0].iov_base;
1456 	__u16 count;
1457 	struct kvec rsp_iov = { NULL, 0 };
1458 
1459 	count = sess_data->iov[1].iov_len + sess_data->iov[2].iov_len;
1460 	be32_add_cpu(&smb_buf->smb_buf_length, count);
1461 	put_bcc(count, smb_buf);
1462 
1463 	rc = SendReceive2(sess_data->xid, sess_data->ses,
1464 			  sess_data->iov, 3 /* num_iovecs */,
1465 			  &sess_data->buf0_type,
1466 			  CIFS_LOG_ERROR, &rsp_iov);
1467 	cifs_small_buf_release(sess_data->iov[0].iov_base);
1468 	memcpy(&sess_data->iov[0], &rsp_iov, sizeof(struct kvec));
1469 
1470 	return rc;
1471 }
1472 
1473 static void
sess_auth_ntlmv2(struct sess_data * sess_data)1474 sess_auth_ntlmv2(struct sess_data *sess_data)
1475 {
1476 	int rc = 0;
1477 	struct smb_hdr *smb_buf;
1478 	SESSION_SETUP_ANDX *pSMB;
1479 	char *bcc_ptr;
1480 	struct cifs_ses *ses = sess_data->ses;
1481 	struct TCP_Server_Info *server = sess_data->server;
1482 	__u32 capabilities;
1483 	__u16 bytes_remaining;
1484 
1485 	/* old style NTLM sessionsetup */
1486 	/* wct = 13 */
1487 	rc = sess_alloc_buffer(sess_data, 13);
1488 	if (rc)
1489 		goto out;
1490 
1491 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1492 	bcc_ptr = sess_data->iov[2].iov_base;
1493 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1494 
1495 	pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
1496 
1497 	/* LM2 password would be here if we supported it */
1498 	pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
1499 
1500 	if (ses->user_name != NULL) {
1501 		/* calculate nlmv2 response and session key */
1502 		rc = setup_ntlmv2_rsp(ses, sess_data->nls_cp);
1503 		if (rc) {
1504 			cifs_dbg(VFS, "Error %d during NTLMv2 authentication\n", rc);
1505 			goto out;
1506 		}
1507 
1508 		memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
1509 				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1510 		bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
1511 
1512 		/* set case sensitive password length after tilen may get
1513 		 * assigned, tilen is 0 otherwise.
1514 		 */
1515 		pSMB->req_no_secext.CaseSensitivePasswordLength =
1516 			cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1517 	} else {
1518 		pSMB->req_no_secext.CaseSensitivePasswordLength = 0;
1519 	}
1520 
1521 	if (ses->capabilities & CAP_UNICODE) {
1522 		if (!IS_ALIGNED(sess_data->iov[0].iov_len, 2)) {
1523 			*bcc_ptr = 0;
1524 			bcc_ptr++;
1525 		}
1526 		unicode_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1527 	} else {
1528 		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1529 	}
1530 
1531 
1532 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1533 			(long) sess_data->iov[2].iov_base;
1534 
1535 	rc = sess_sendreceive(sess_data);
1536 	if (rc)
1537 		goto out;
1538 
1539 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1540 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1541 
1542 	if (smb_buf->WordCount != 3) {
1543 		rc = -EIO;
1544 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1545 		goto out;
1546 	}
1547 
1548 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1549 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1550 
1551 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1552 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1553 
1554 	bytes_remaining = get_bcc(smb_buf);
1555 	bcc_ptr = pByteArea(smb_buf);
1556 
1557 	/* BB check if Unicode and decode strings */
1558 	if (bytes_remaining == 0) {
1559 		/* no string area to decode, do nothing */
1560 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1561 		/* unicode string area must be word-aligned */
1562 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1563 			++bcc_ptr;
1564 			--bytes_remaining;
1565 		}
1566 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1567 				      sess_data->nls_cp);
1568 	} else {
1569 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1570 				    sess_data->nls_cp);
1571 	}
1572 
1573 	rc = sess_establish_session(sess_data);
1574 out:
1575 	sess_data->result = rc;
1576 	sess_data->func = NULL;
1577 	sess_free_buffer(sess_data);
1578 	kfree_sensitive(ses->auth_key.response);
1579 	ses->auth_key.response = NULL;
1580 }
1581 
1582 #ifdef CONFIG_CIFS_UPCALL
1583 static void
sess_auth_kerberos(struct sess_data * sess_data)1584 sess_auth_kerberos(struct sess_data *sess_data)
1585 {
1586 	int rc = 0;
1587 	struct smb_hdr *smb_buf;
1588 	SESSION_SETUP_ANDX *pSMB;
1589 	char *bcc_ptr;
1590 	struct cifs_ses *ses = sess_data->ses;
1591 	struct TCP_Server_Info *server = sess_data->server;
1592 	__u32 capabilities;
1593 	__u16 bytes_remaining;
1594 	struct key *spnego_key = NULL;
1595 	struct cifs_spnego_msg *msg;
1596 	u16 blob_len;
1597 
1598 	/* extended security */
1599 	/* wct = 12 */
1600 	rc = sess_alloc_buffer(sess_data, 12);
1601 	if (rc)
1602 		goto out;
1603 
1604 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1605 	bcc_ptr = sess_data->iov[2].iov_base;
1606 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1607 
1608 	spnego_key = cifs_get_spnego_key(ses, server);
1609 	if (IS_ERR(spnego_key)) {
1610 		rc = PTR_ERR(spnego_key);
1611 		spnego_key = NULL;
1612 		goto out;
1613 	}
1614 
1615 	msg = spnego_key->payload.data[0];
1616 	/*
1617 	 * check version field to make sure that cifs.upcall is
1618 	 * sending us a response in an expected form
1619 	 */
1620 	if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
1621 		cifs_dbg(VFS, "incorrect version of cifs.upcall (expected %d but got %d)\n",
1622 			 CIFS_SPNEGO_UPCALL_VERSION, msg->version);
1623 		rc = -EKEYREJECTED;
1624 		goto out_put_spnego_key;
1625 	}
1626 
1627 	kfree_sensitive(ses->auth_key.response);
1628 	ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
1629 					 GFP_KERNEL);
1630 	if (!ses->auth_key.response) {
1631 		cifs_dbg(VFS, "Kerberos can't allocate (%u bytes) memory\n",
1632 			 msg->sesskey_len);
1633 		rc = -ENOMEM;
1634 		goto out_put_spnego_key;
1635 	}
1636 	ses->auth_key.len = msg->sesskey_len;
1637 
1638 	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
1639 	capabilities |= CAP_EXTENDED_SECURITY;
1640 	pSMB->req.Capabilities = cpu_to_le32(capabilities);
1641 	sess_data->iov[1].iov_base = msg->data + msg->sesskey_len;
1642 	sess_data->iov[1].iov_len = msg->secblob_len;
1643 	pSMB->req.SecurityBlobLength = cpu_to_le16(sess_data->iov[1].iov_len);
1644 
1645 	if (pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) {
1646 		/* unicode strings must be word aligned */
1647 		if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
1648 			*bcc_ptr = 0;
1649 			bcc_ptr++;
1650 		}
1651 		unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1652 		unicode_domain_string(&bcc_ptr, ses, sess_data->nls_cp);
1653 	} else {
1654 		ascii_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1655 		ascii_domain_string(&bcc_ptr, ses, sess_data->nls_cp);
1656 	}
1657 
1658 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1659 			(long) sess_data->iov[2].iov_base;
1660 
1661 	rc = sess_sendreceive(sess_data);
1662 	if (rc)
1663 		goto out_put_spnego_key;
1664 
1665 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1666 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1667 
1668 	if (smb_buf->WordCount != 4) {
1669 		rc = -EIO;
1670 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1671 		goto out_put_spnego_key;
1672 	}
1673 
1674 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1675 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1676 
1677 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1678 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1679 
1680 	bytes_remaining = get_bcc(smb_buf);
1681 	bcc_ptr = pByteArea(smb_buf);
1682 
1683 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1684 	if (blob_len > bytes_remaining) {
1685 		cifs_dbg(VFS, "bad security blob length %d\n",
1686 				blob_len);
1687 		rc = -EINVAL;
1688 		goto out_put_spnego_key;
1689 	}
1690 	bcc_ptr += blob_len;
1691 	bytes_remaining -= blob_len;
1692 
1693 	/* BB check if Unicode and decode strings */
1694 	if (bytes_remaining == 0) {
1695 		/* no string area to decode, do nothing */
1696 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1697 		/* unicode string area must be word-aligned */
1698 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1699 			++bcc_ptr;
1700 			--bytes_remaining;
1701 		}
1702 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1703 				      sess_data->nls_cp);
1704 	} else {
1705 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1706 				    sess_data->nls_cp);
1707 	}
1708 
1709 	rc = sess_establish_session(sess_data);
1710 out_put_spnego_key:
1711 	key_invalidate(spnego_key);
1712 	key_put(spnego_key);
1713 out:
1714 	sess_data->result = rc;
1715 	sess_data->func = NULL;
1716 	sess_free_buffer(sess_data);
1717 	kfree_sensitive(ses->auth_key.response);
1718 	ses->auth_key.response = NULL;
1719 }
1720 
1721 #endif /* ! CONFIG_CIFS_UPCALL */
1722 
1723 /*
1724  * The required kvec buffers have to be allocated before calling this
1725  * function.
1726  */
1727 static int
_sess_auth_rawntlmssp_assemble_req(struct sess_data * sess_data)1728 _sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
1729 {
1730 	SESSION_SETUP_ANDX *pSMB;
1731 	struct cifs_ses *ses = sess_data->ses;
1732 	struct TCP_Server_Info *server = sess_data->server;
1733 	__u32 capabilities;
1734 	char *bcc_ptr;
1735 
1736 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1737 
1738 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1739 	if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
1740 		cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
1741 		return -ENOSYS;
1742 	}
1743 
1744 	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
1745 	capabilities |= CAP_EXTENDED_SECURITY;
1746 	pSMB->req.Capabilities |= cpu_to_le32(capabilities);
1747 
1748 	bcc_ptr = sess_data->iov[2].iov_base;
1749 	/* unicode strings must be word aligned */
1750 	if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
1751 		*bcc_ptr = 0;
1752 		bcc_ptr++;
1753 	}
1754 	unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1755 
1756 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1757 					(long) sess_data->iov[2].iov_base;
1758 
1759 	return 0;
1760 }
1761 
1762 static void
1763 sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data);
1764 
1765 static void
sess_auth_rawntlmssp_negotiate(struct sess_data * sess_data)1766 sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
1767 {
1768 	int rc;
1769 	struct smb_hdr *smb_buf;
1770 	SESSION_SETUP_ANDX *pSMB;
1771 	struct cifs_ses *ses = sess_data->ses;
1772 	struct TCP_Server_Info *server = sess_data->server;
1773 	__u16 bytes_remaining;
1774 	char *bcc_ptr;
1775 	unsigned char *ntlmsspblob = NULL;
1776 	u16 blob_len;
1777 
1778 	cifs_dbg(FYI, "rawntlmssp session setup negotiate phase\n");
1779 
1780 	/*
1781 	 * if memory allocation is successful, caller of this function
1782 	 * frees it.
1783 	 */
1784 	ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
1785 	if (!ses->ntlmssp) {
1786 		rc = -ENOMEM;
1787 		goto out;
1788 	}
1789 	ses->ntlmssp->sesskey_per_smbsess = false;
1790 
1791 	/* wct = 12 */
1792 	rc = sess_alloc_buffer(sess_data, 12);
1793 	if (rc)
1794 		goto out;
1795 
1796 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1797 
1798 	/* Build security blob before we assemble the request */
1799 	rc = build_ntlmssp_negotiate_blob(&ntlmsspblob,
1800 				     &blob_len, ses, server,
1801 				     sess_data->nls_cp);
1802 	if (rc)
1803 		goto out_free_ntlmsspblob;
1804 
1805 	sess_data->iov[1].iov_len = blob_len;
1806 	sess_data->iov[1].iov_base = ntlmsspblob;
1807 	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
1808 
1809 	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
1810 	if (rc)
1811 		goto out_free_ntlmsspblob;
1812 
1813 	rc = sess_sendreceive(sess_data);
1814 
1815 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1816 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1817 
1818 	/* If true, rc here is expected and not an error */
1819 	if (sess_data->buf0_type != CIFS_NO_BUFFER &&
1820 	    smb_buf->Status.CifsError ==
1821 			cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))
1822 		rc = 0;
1823 
1824 	if (rc)
1825 		goto out_free_ntlmsspblob;
1826 
1827 	cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n");
1828 
1829 	if (smb_buf->WordCount != 4) {
1830 		rc = -EIO;
1831 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1832 		goto out_free_ntlmsspblob;
1833 	}
1834 
1835 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1836 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1837 
1838 	bytes_remaining = get_bcc(smb_buf);
1839 	bcc_ptr = pByteArea(smb_buf);
1840 
1841 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1842 	if (blob_len > bytes_remaining) {
1843 		cifs_dbg(VFS, "bad security blob length %d\n",
1844 				blob_len);
1845 		rc = -EINVAL;
1846 		goto out_free_ntlmsspblob;
1847 	}
1848 
1849 	rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
1850 
1851 out_free_ntlmsspblob:
1852 	kfree_sensitive(ntlmsspblob);
1853 out:
1854 	sess_free_buffer(sess_data);
1855 
1856 	if (!rc) {
1857 		sess_data->func = sess_auth_rawntlmssp_authenticate;
1858 		return;
1859 	}
1860 
1861 	/* Else error. Cleanup */
1862 	kfree_sensitive(ses->auth_key.response);
1863 	ses->auth_key.response = NULL;
1864 	kfree_sensitive(ses->ntlmssp);
1865 	ses->ntlmssp = NULL;
1866 
1867 	sess_data->func = NULL;
1868 	sess_data->result = rc;
1869 }
1870 
1871 static void
sess_auth_rawntlmssp_authenticate(struct sess_data * sess_data)1872 sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
1873 {
1874 	int rc;
1875 	struct smb_hdr *smb_buf;
1876 	SESSION_SETUP_ANDX *pSMB;
1877 	struct cifs_ses *ses = sess_data->ses;
1878 	struct TCP_Server_Info *server = sess_data->server;
1879 	__u16 bytes_remaining;
1880 	char *bcc_ptr;
1881 	unsigned char *ntlmsspblob = NULL;
1882 	u16 blob_len;
1883 
1884 	cifs_dbg(FYI, "rawntlmssp session setup authenticate phase\n");
1885 
1886 	/* wct = 12 */
1887 	rc = sess_alloc_buffer(sess_data, 12);
1888 	if (rc)
1889 		goto out;
1890 
1891 	/* Build security blob before we assemble the request */
1892 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1893 	smb_buf = (struct smb_hdr *)pSMB;
1894 	rc = build_ntlmssp_auth_blob(&ntlmsspblob,
1895 					&blob_len, ses, server,
1896 					sess_data->nls_cp);
1897 	if (rc)
1898 		goto out_free_ntlmsspblob;
1899 	sess_data->iov[1].iov_len = blob_len;
1900 	sess_data->iov[1].iov_base = ntlmsspblob;
1901 	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
1902 	/*
1903 	 * Make sure that we tell the server that we are using
1904 	 * the uid that it just gave us back on the response
1905 	 * (challenge)
1906 	 */
1907 	smb_buf->Uid = ses->Suid;
1908 
1909 	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
1910 	if (rc)
1911 		goto out_free_ntlmsspblob;
1912 
1913 	rc = sess_sendreceive(sess_data);
1914 	if (rc)
1915 		goto out_free_ntlmsspblob;
1916 
1917 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1918 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1919 	if (smb_buf->WordCount != 4) {
1920 		rc = -EIO;
1921 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1922 		goto out_free_ntlmsspblob;
1923 	}
1924 
1925 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1926 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1927 
1928 	if (ses->Suid != smb_buf->Uid) {
1929 		ses->Suid = smb_buf->Uid;
1930 		cifs_dbg(FYI, "UID changed! new UID = %llu\n", ses->Suid);
1931 	}
1932 
1933 	bytes_remaining = get_bcc(smb_buf);
1934 	bcc_ptr = pByteArea(smb_buf);
1935 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1936 	if (blob_len > bytes_remaining) {
1937 		cifs_dbg(VFS, "bad security blob length %d\n",
1938 				blob_len);
1939 		rc = -EINVAL;
1940 		goto out_free_ntlmsspblob;
1941 	}
1942 	bcc_ptr += blob_len;
1943 	bytes_remaining -= blob_len;
1944 
1945 
1946 	/* BB check if Unicode and decode strings */
1947 	if (bytes_remaining == 0) {
1948 		/* no string area to decode, do nothing */
1949 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1950 		/* unicode string area must be word-aligned */
1951 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1952 			++bcc_ptr;
1953 			--bytes_remaining;
1954 		}
1955 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1956 				      sess_data->nls_cp);
1957 	} else {
1958 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1959 				    sess_data->nls_cp);
1960 	}
1961 
1962 out_free_ntlmsspblob:
1963 	kfree_sensitive(ntlmsspblob);
1964 out:
1965 	sess_free_buffer(sess_data);
1966 
1967 	if (!rc)
1968 		rc = sess_establish_session(sess_data);
1969 
1970 	/* Cleanup */
1971 	kfree_sensitive(ses->auth_key.response);
1972 	ses->auth_key.response = NULL;
1973 	kfree_sensitive(ses->ntlmssp);
1974 	ses->ntlmssp = NULL;
1975 
1976 	sess_data->func = NULL;
1977 	sess_data->result = rc;
1978 }
1979 
select_sec(struct sess_data * sess_data)1980 static int select_sec(struct sess_data *sess_data)
1981 {
1982 	int type;
1983 	struct cifs_ses *ses = sess_data->ses;
1984 	struct TCP_Server_Info *server = sess_data->server;
1985 
1986 	type = cifs_select_sectype(server, ses->sectype);
1987 	cifs_dbg(FYI, "sess setup type %d\n", type);
1988 	if (type == Unspecified) {
1989 		cifs_dbg(VFS, "Unable to select appropriate authentication method!\n");
1990 		return -EINVAL;
1991 	}
1992 
1993 	switch (type) {
1994 	case NTLMv2:
1995 		sess_data->func = sess_auth_ntlmv2;
1996 		break;
1997 	case Kerberos:
1998 #ifdef CONFIG_CIFS_UPCALL
1999 		sess_data->func = sess_auth_kerberos;
2000 		break;
2001 #else
2002 		cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
2003 		return -ENOSYS;
2004 #endif /* CONFIG_CIFS_UPCALL */
2005 	case RawNTLMSSP:
2006 		sess_data->func = sess_auth_rawntlmssp_negotiate;
2007 		break;
2008 	default:
2009 		cifs_dbg(VFS, "secType %d not supported!\n", type);
2010 		return -ENOSYS;
2011 	}
2012 
2013 	return 0;
2014 }
2015 
CIFS_SessSetup(const unsigned int xid,struct cifs_ses * ses,struct TCP_Server_Info * server,const struct nls_table * nls_cp)2016 int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
2017 		   struct TCP_Server_Info *server,
2018 		   const struct nls_table *nls_cp)
2019 {
2020 	int rc = 0;
2021 	struct sess_data *sess_data;
2022 
2023 	if (ses == NULL) {
2024 		WARN(1, "%s: ses == NULL!", __func__);
2025 		return -EINVAL;
2026 	}
2027 
2028 	sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
2029 	if (!sess_data)
2030 		return -ENOMEM;
2031 
2032 	sess_data->xid = xid;
2033 	sess_data->ses = ses;
2034 	sess_data->server = server;
2035 	sess_data->buf0_type = CIFS_NO_BUFFER;
2036 	sess_data->nls_cp = (struct nls_table *) nls_cp;
2037 
2038 	rc = select_sec(sess_data);
2039 	if (rc)
2040 		goto out;
2041 
2042 	while (sess_data->func)
2043 		sess_data->func(sess_data);
2044 
2045 	/* Store result before we free sess_data */
2046 	rc = sess_data->result;
2047 
2048 out:
2049 	kfree_sensitive(sess_data);
2050 	return rc;
2051 }
2052 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
2053